This study centered on biogas production from locally available animal and kitchen wastes: swine dung (SD), plantain peel (PP) and fluted pumpkin stem (PS) using five 32-Litres metallic prototype digesters. The anaerobic digestion was in the ratio of 3:1 of water to waste for all the samples as follows: Sample A was 100%SD, Sample B; 100% PP, Sample C; 100% PS, Sample D; 50%SD+50%PP and Sample E; 40% SD+30% PP+30% PS. The retention time was 30 days and parameters like pH, pressure, daily biogas production, ambient and slurry temperatures alongside the physico-chemical properties of wastes were monitored. The cumulative gas production yield was 11.5L, 35.1L, 39.5L, 46.9L, 59.3L for Sample A, Sample B, Sample C, Sample D and Sample E respectively. The flammable time was 15th, 5th, 25th, 26th, 2nd day for sample A, sample B, sample C, sample D and sample E respectively. The result revealed that the blend of the 3 substrates i.e. sample E: 40% SD+30% PP+30% PS gave the highest yield of biogas and flamed earlier than the other samples while sample A: 100%SD had the lowest yield of biogas. The results also showed that the sample that had the highest composition of methane in the biogas produced was Sample D: 50%SD+50%PP with 85.6989% while the lowest composition of methane was found in Sample C to be 79.0996%. The TS, TVS, BOD and VS were seen to be consistently reducing showing the level of waste treatment achieved during the digestion period of 30 days.
This document summarizes an experimental study on generating biogas from kitchen waste and cow dung. The study found that (1) Kitchen waste produced 150.69% more biogas than cow dung alone, showing it is a more efficient substrate. (2) Biogas production initially increased for 3 days then decreased as acid concentration rose, lowering the pH. Adding water increased the pH and biogas production. (3) The pH decreased more rapidly for the kitchen waste setup, indicating it underwent hydrolysis and acidogenesis faster than the cow dung setup. In conclusion, the study found that kitchen waste is a better alternative substrate than cow dung alone for generating more biogas and producing a useful byproduct with better anaer
The document summarizes a study that investigated the effect of inoculum to substrate ratio on biogas production from anaerobically digested goat paunch manure. Goat paunch manure was digested at different inoculum to substrate ratios of 1.45, 2.2, and 4.3 in biodigesters labeled R15, R10, and R5, respectively, under mesophilic conditions. Results showed that biogas production rate peaked earliest in R10 and latest in R15, but inoculum to substrate ratio did not significantly affect production rate. However, biogas production accumulation increased from 0.44273 to 1.00783 Nm3/kg VS with increasing inoculum to substrate ratio
This document summarizes research on biogas production from chicken manure through anaerobic digestion. The researchers conducted a full-scale analysis of biogas production from chicken manure over 217 days. They found that an acclimation period is required for the anaerobic digestion process to adapt to the manure feedstock. During acclimation, biogas production and process efficiency decreased due to ammonium inhibition but later stabilized. The study determined that chicken manure has the potential to produce 312±23 L of methane per kg of volatile solids added. Once adapted, the anaerobic digestion system was able to process over 5,000 tons of manure with 93% efficiency at an organic loading rate of 3.14
— Municipal Solid Waste (MSW), mainly Kitchen Waste
(K) with Cow Dung (C) and Fungi Culture (F) can be used to
generate energy which could save on the fossil fuels conventionally
used as source of energy. In this study, the possibility was
explored to mix Cow Dung with Fungi Culture for anaerobic
digestion, so that energy can be generated as biogas and at the
same time digested sludge can be used as fertilizer for agricultural
applications. Pre-treatment of Kitchen Waste was done by alkali
method. Anaerobic digestion (AD) was carried out in mesophilic
temperature range of 30°C to 37°C with different fermentation
slurries of 8 % total solids. Digestion was carried for a retention
period of 60 days. The gas produced was collected by the
downward displacement of water and was subsequently measured
and analyzed. The overall results showed that blending of Kitchen
waste with cow dung and fungi culture (Aspergillus flavus) had
significant improvement on the biogas yield.
This document summarizes a study that optimized biogas production from poultry manure wastewater through anaerobic digestion. The poultry manure was characterized, pre-treated to remove excess ammonia, and used as a substrate. A central composite design was used to investigate the effects of agitation rate and reaction time on biogas yield. The maximum biogas yield of 4.45 mL/g COD occurred at 120 rpm agitation and 3.3 days reaction time.
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
The papers for publication in The International Journal of Engineering& Science are selected through rigorous peer reviews to ensure originality, timeliness, relevance, and readability.
Performance Evaluation of the Effect of pH and Temperature on the Biogas Yiel...ijtsrd
In this research work, the effect of pH and temperature on the biogas yield of co-digestion of Pig manure and water hyacinth were investigated experimentally in laboratory scale anaerobic bioreactors. The co-digestion was run for a Hydraulic Retention Time thirty six days. The volumetric yield of biogas was noted once there is biogas build up at regular intervals using water displacement method. A total of ten evacuations were made and the data obtained was used to evaluate the effect of the aforementioned anaerobic digestion parameters. The experimental results revealed that a neutral pH value of 7 yielded optimum biogas yields compared to a pH value above and below 7. Moreover, from all the experimental mesophilic temperature used in this research work, an optimum mesophilic temperature of 37 oC favoured the optimum biogas yield. Nse Peter Essang "Performance Evaluation of the Effect of pH and Temperature on the Biogas Yield of Co-Digestion of Pig Manure and Water Hyacinth" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-3 | Issue-2 , February 2019, URL: https://www.ijtsrd.com/papers/ijtsrd21410.pdf
Paper URL: https://www.ijtsrd.com/engineering/gas-engineering/21410/performance-evaluation-of-the-effect-of-ph-and-temperature-on-the-biogas-yield-of-co-digestion-of-pig-manure-and-water-hyacinth/nse-peter-essang
Welcome to International Journal of Engineering Research and Development (IJERD)IJERD Editor
call for paper 2012, hard copy of journal, research paper publishing, where to publish research paper,
journal publishing, how to publish research paper, Call For research paper, international journal, publishing a paper, IJERD, journal of science and technology, how to get a research paper published, publishing a paper, publishing of journal, publishing of research paper, reserach and review articles, IJERD Journal, How to publish your research paper, publish research paper, open access engineering journal, Engineering journal, Mathemetics journal, Physics journal, Chemistry journal, Computer Engineering, Computer Science journal, how to submit your paper, peer reviw journal, indexed journal, reserach and review articles, engineering journal, www.ijerd.com, research journals
This document summarizes an experimental study on generating biogas from kitchen waste and cow dung. The study found that (1) Kitchen waste produced 150.69% more biogas than cow dung alone, showing it is a more efficient substrate. (2) Biogas production initially increased for 3 days then decreased as acid concentration rose, lowering the pH. Adding water increased the pH and biogas production. (3) The pH decreased more rapidly for the kitchen waste setup, indicating it underwent hydrolysis and acidogenesis faster than the cow dung setup. In conclusion, the study found that kitchen waste is a better alternative substrate than cow dung alone for generating more biogas and producing a useful byproduct with better anaer
The document summarizes a study that investigated the effect of inoculum to substrate ratio on biogas production from anaerobically digested goat paunch manure. Goat paunch manure was digested at different inoculum to substrate ratios of 1.45, 2.2, and 4.3 in biodigesters labeled R15, R10, and R5, respectively, under mesophilic conditions. Results showed that biogas production rate peaked earliest in R10 and latest in R15, but inoculum to substrate ratio did not significantly affect production rate. However, biogas production accumulation increased from 0.44273 to 1.00783 Nm3/kg VS with increasing inoculum to substrate ratio
This document summarizes research on biogas production from chicken manure through anaerobic digestion. The researchers conducted a full-scale analysis of biogas production from chicken manure over 217 days. They found that an acclimation period is required for the anaerobic digestion process to adapt to the manure feedstock. During acclimation, biogas production and process efficiency decreased due to ammonium inhibition but later stabilized. The study determined that chicken manure has the potential to produce 312±23 L of methane per kg of volatile solids added. Once adapted, the anaerobic digestion system was able to process over 5,000 tons of manure with 93% efficiency at an organic loading rate of 3.14
— Municipal Solid Waste (MSW), mainly Kitchen Waste
(K) with Cow Dung (C) and Fungi Culture (F) can be used to
generate energy which could save on the fossil fuels conventionally
used as source of energy. In this study, the possibility was
explored to mix Cow Dung with Fungi Culture for anaerobic
digestion, so that energy can be generated as biogas and at the
same time digested sludge can be used as fertilizer for agricultural
applications. Pre-treatment of Kitchen Waste was done by alkali
method. Anaerobic digestion (AD) was carried out in mesophilic
temperature range of 30°C to 37°C with different fermentation
slurries of 8 % total solids. Digestion was carried for a retention
period of 60 days. The gas produced was collected by the
downward displacement of water and was subsequently measured
and analyzed. The overall results showed that blending of Kitchen
waste with cow dung and fungi culture (Aspergillus flavus) had
significant improvement on the biogas yield.
This document summarizes a study that optimized biogas production from poultry manure wastewater through anaerobic digestion. The poultry manure was characterized, pre-treated to remove excess ammonia, and used as a substrate. A central composite design was used to investigate the effects of agitation rate and reaction time on biogas yield. The maximum biogas yield of 4.45 mL/g COD occurred at 120 rpm agitation and 3.3 days reaction time.
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
The papers for publication in The International Journal of Engineering& Science are selected through rigorous peer reviews to ensure originality, timeliness, relevance, and readability.
Performance Evaluation of the Effect of pH and Temperature on the Biogas Yiel...ijtsrd
In this research work, the effect of pH and temperature on the biogas yield of co-digestion of Pig manure and water hyacinth were investigated experimentally in laboratory scale anaerobic bioreactors. The co-digestion was run for a Hydraulic Retention Time thirty six days. The volumetric yield of biogas was noted once there is biogas build up at regular intervals using water displacement method. A total of ten evacuations were made and the data obtained was used to evaluate the effect of the aforementioned anaerobic digestion parameters. The experimental results revealed that a neutral pH value of 7 yielded optimum biogas yields compared to a pH value above and below 7. Moreover, from all the experimental mesophilic temperature used in this research work, an optimum mesophilic temperature of 37 oC favoured the optimum biogas yield. Nse Peter Essang "Performance Evaluation of the Effect of pH and Temperature on the Biogas Yield of Co-Digestion of Pig Manure and Water Hyacinth" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-3 | Issue-2 , February 2019, URL: https://www.ijtsrd.com/papers/ijtsrd21410.pdf
Paper URL: https://www.ijtsrd.com/engineering/gas-engineering/21410/performance-evaluation-of-the-effect-of-ph-and-temperature-on-the-biogas-yield-of-co-digestion-of-pig-manure-and-water-hyacinth/nse-peter-essang
Welcome to International Journal of Engineering Research and Development (IJERD)IJERD Editor
call for paper 2012, hard copy of journal, research paper publishing, where to publish research paper,
journal publishing, how to publish research paper, Call For research paper, international journal, publishing a paper, IJERD, journal of science and technology, how to get a research paper published, publishing a paper, publishing of journal, publishing of research paper, reserach and review articles, IJERD Journal, How to publish your research paper, publish research paper, open access engineering journal, Engineering journal, Mathemetics journal, Physics journal, Chemistry journal, Computer Engineering, Computer Science journal, how to submit your paper, peer reviw journal, indexed journal, reserach and review articles, engineering journal, www.ijerd.com, research journals
Effect of co digestion on anaerobic digestion of cattle slurry with maize cob...Alexander Decker
1) Researchers investigated the effect of co-digesting cattle slurry and maize cob at different ratios (3:1, 1:1, 1:3 cattle slurry to maize cob) on biogas and methane production under mesophilic temperature (37°C).
2) Co-digesting cattle slurry and maize cob at a 3:1 ratio produced the highest biogas yield of 453.38 lN/kg oDM and methane yield of 334.18 lNCH4/kg oDM.
3) Methane concentrations ranged from 73.71% to 77.55% depending on the ratio, with the highest concentration obtained at a 1:1 ratio of cattle sl
Agricultural potential of biosolids generated from dewatering of faecal sludg...Alexander Decker
The document summarizes a study that evaluated the agricultural potential of biosolids produced from dewatering faecal sludge on drying beds in Ghana. Various filter media and loading rates of faecal sludge were tested. Nutrients like carbon, nitrogen, phosphorus and potassium were within ranges that would support agricultural use. Heavy metal concentrations in the biosolids were very low and below limits for use in developing countries. The results indicate the biosolids have nutrient value and low risk of heavy metal contamination, suggesting potential for use as fertilizer in agriculture.
The document summarizes a research study that exposed mice to the gaseous fraction of emissions from cashew nut shell combustion. Key findings include:
1) Exposure to the gaseous fraction resulted in changes to respiratory system mechanics, oxidative stress levels, and histopathological lung changes in mice.
2) While filters are used to remove particulate matter from biomass combustion emissions, the study demonstrates that the gaseous fraction still causes harmful health effects and requires attention.
3) The study analyzed the combustion process and chemical composition of the gaseous fraction to better understand its toxic effects on the respiratory system.
Comparison of kinetic models for biogas production rate from saw dusteSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Effect of different bulking materials and earthworms species on bioremediatio...Alexander Decker
This study investigated the effect of different bulking materials (cow dung, sheep manure, garden soil) and earthworm species (Eudrilus eugeniae and Eisenia foetida) on the bioremediation of municipal sewage sludge. The results showed that interactions between worm species and bulking materials significantly affected moisture content, EC, and chloride levels but not pH or organic carbon. Organic carbon, EC, and chloride levels generally decreased from the initial to final stages of vermiremediation. The combination of cow dung and Eudrilus eugeniae led to the lowest levels of EC, organic carbon, and chloride, indicating it was the most effective treatment for bioremedi
Environmental Engineering for Enhancing the Suitability of a Microalga for En...IRJET Journal
This document discusses research conducted on the microalga Chlorella vulgaris to study the effects of varying pH and salinity on its growth, biomass production, and lipid content. The researchers found that growth and biomass were highest at pH 7, while lipid content increased with higher salinity up to 0.25M, beyond which growth decreased. The goal was to optimize environmental conditions to enhance the suitability of C. vulgaris for renewable energy production through biomass and lipid accumulation.
This document summarizes a study that analyzed changes in bacterial and archaeal communities during thermophilic composting of cattle manure using PhyloChip microarray technology. Samples were collected from different areas of a compost pile based on age and temperature. Total DNA was extracted from the samples and the 16S rRNA gene was amplified and hybridized to a PhyloChip array. Statistical analysis showed differences in microbial populations between raw manure samples and compost samples. During composting, archaeal phyla Thaumarchaeota and Thermoprotei and bacterial phyla Actinobacteria and Firmicutes increased in diversity. Ammonia-oxidizing and methanogenic microbes increased under thermophilic conditions. The
This document evaluates the effect of 15 kGy gamma radiation on eight different agro-waste materials for cultivation of oyster mushrooms (Pleurotus eous strain P-31). Corn cobs performed the best overall with the fastest mycelia colonization rate, shortest colonization time, no contamination, and highest density. It also had the largest cap diameter, longest stipe length, most primordia and fruit bodies, largest mushroom size, and shortest time between flushes. Corn cobs achieved the highest biological efficiency of 63% and mushroom yield of 377g. The gamma irradiated substrates significantly influenced mushroom growth and yield. Gamma irradiation is concluded to be a potential alternative method for pretreating lignocell
This document provides information on sediment composition, sediment contamination, remediation technologies for contaminated sediments, and their applications and trends. It discusses the components and contaminants commonly found in sediments. The key contaminant characteristics affecting treatment are described. Major remediation technologies discussed include dredging, capping, solidification, biostimulation, bioaugmentation, and monitored natural recovery. Emerging integrated technologies like in situ phase inversion emulsification and biological reductive dechlorination are introduced. Benchmark comparisons of laboratory and field studies on contaminated sediment remediation are provided.
Characterization of organic compounds from biosolids of Buenos Aires City, Silvana Torri
This study characterized the organic compounds in biosolids from Buenos Aires, Argentina. Different solvents were evaluated for ultrasound-assisted extraction (UAE) and a hexane:acetone mixture provided the highest extractability. The organic compounds identified included fatty acids, n-alkanes, and steroids. Persistent organic pollutants were below detection limits. The recalcitrant organic fraction reported previously is mainly due to stable sterols in the biosolids.
World reserves of petroleum are rapidly depleting, in recent years methane from biogas has emerged as important alternative resource for fuel and chemicals production and has generated a great deal of research interest in methane production. Lignocellulosic biomass is the most abundant organic raw material in the world. Production of methane as second-generation biofuels from renewable lignocellulosic resources may improve energy availability, decrease air pollution and diminish atmospheric CO2 emissions. The use of wheat straw does not affect the food supply; thus, wheat straw was analyzed as a raw material for second-generation biofuels production. The aim of this paper is to present a thermodynamic analysis for methane production from lignin-based aromatics (vanillin) with the method of Gibbs free energy minimization using the Aspen Plus® simulator. The analysis was carried out using the interval 350-1500 K, feeding a H2O/Vanillin ratio (WVR) of 0.6 to 5.0, 1 atm. The results showed that the vanillin conversion was almost completed, except at the highest vanillin feed concentration, in which the conversion was of 65%. Methane yields from 2 to 4 mol CH4/mol vanillin were obtained at high and low vanillin feed concentrations, respectively, when operating at low temperature.
Using next generation sequencing to describe epiphytic microbiota associated ...Agriculture Journal IJOEAR
Abstract— Its seems likely that agricultural management as diverse as certified organic and conventional IPM practices would impact the microbiota associated with crop surfaces differently. We sampled organic and conventionally managed apples at multiple time-points in a growing season and characterized the bacterial taxa associated with replicates of each treatment type. Surprisingly, no evidence of significant differences persisting across multiple time-points was observed. Significant differential abundance of certain taxa was documented but when it was, it was primarily associated with a single time-point making it difficult to understand if these observations resulted from an environmental or a treatment effect. Principal component analyses demonstrated that sampling time-point explained more of the differences between bacterial communities than treatment. Description of dominant shared bacterial families for both organic and conventional samples included Oxalobacteraceae, Pseudomonadaceae, Sphingomonadaceae and Enterobacteriaceae.
Effect of wheat straw components on the yield of pleurotus eousDr. siddhant
The document presents research on the effect of different components of wheat straw (leaves, leaf sheaths, and stems of various sizes) on mushroom yield when grown on Pleurotus eous. Small and large stem pieces (1.0-1.7cm) produced the highest yields of 341-336 grams respectively, with a biological efficiency of 67.2-68.2%. Fine leaves and leaf sheaths (0.2cm) yielded the least at 218 grams with 43.6% efficiency due to having less nutrients and being more susceptible to contamination. Overall, stems were found to be the best wheat straw component for cultivating P. eous mushrooms.
Bioremediating Effect of Glomus Hoi and Pseudomonas Aeruginosa on the Organic...IJEAB
This study analyzed the degrading effect of Glomus hoi and Pseudomonas aeruginosa on the organic content and heavy metals of oil refinery effluent polluted soil using Amaranthus cruentus as the test plant. This study was carried out to determine if agricultural activities can be improved using any or both of the micoorganisms. Eight different treatment layouts were used with three replicates for each level of pollution in the treatment layout. Ninety six (96) pots, each containing three kilograms of soil from both sterilized and unsterilized soil were used for the study. Fifty (50) grams of soil inoculum from propagated Arbuscular mycorrhiza was inoculated to a set of twenty four (24) experimental pots containing both sterilized and unsterilized soil before A. cruentus seedlings were transplanted to them. Another set of twenty four (24) pots containing both sterilized and unsterilized soil were injected with thirty (30) mL of P. aeruginosa inoculum solution before transplanting A. cruentus seedlings to them. The third set of twenty four (24) pots received dual inoculation of both fifty (50) grams of soil inoculum containing G. hoi and thirty (30) mL of P. aeruginosa inoculum solution before A. cruentus were transplanted to them. The residual twenty four (24) pots served as the control. Thereafter, pot preparation was arranged in the screenhouse in a randomized block design. The A. cruentus seedlings were raised in nursery for a period of two weeks before they were transplanted to the pots, seedlings were left for 3 days to overcome transplanting shock before contaminating the soil with refinery effluent at various concentrations of 0%, 2%, 4% and 6% v/w. The seedlings were allowed to grow for eight weeks before the termination of the experiment. The pre planting analysis of soil showed that heavy metals analyses (zinc and iron) of sterilized soil had a lower concentration to the unsterilized. The soil pH ranged from 6.3 to 6.8. It also revealed that organic matter and organic carbon content ranged from 0.8% to 1.3% and 0.4% to 1.7%. However, after the experiment, it was discovered in this study that treatments without any microorganism inoculation in sterilized and unsterilized soil had a higher level of % organic carbon and % organic matter content compared to the other treatments that were inoculated with one or two micro-organisms across all the levels of effluent concentration. Heavy metals of soil in all the soil samples were found to increase as the petrochemical effluent increased in concentration. The results obtained were analyzed using Duncan Multiple Range Test (DMRT) and other descriptive statistics. This study opined that the combined use of G. hoi and P. aeruginosa was more effective in improving the organic contentand the reduce heavy metals of oil refinery effluent polluted soil than when either is used singly.
Anaerobicaly - Composted Environmental Wastes as Organic Fertilizer and Ident...Oyeniyi Samuel
This document summarizes a study that anaerobically composted sawdust, wood shavings, and poultry manure to produce organic fertilizer. The compost was high in nutrients like organic carbon, nitrogen, phosphorus, and minerals. Nine fungi species were isolated from the compost, including Aspergillus candidus, Aspergillus fumigatus, Penicillium aethiopicum, and Fusarium species. These fungi helped decompose the lignified materials during the composting process. The compost produced was found to be rich in organic matter and nutrients, making it a suitable supplement to inorganic fertilizers for sustainable crop production.
This study evaluated the presence of pathogenic bacteria in fecal samples collected from feral pigs in five counties in Georgia. Quantitative PCR screening detected Brucella suis in 25% of samples and E. coli O157:H7 in 5.5% of samples, but did not detect Campylobacter jejuni. The majority of pigs carrying pathogens came from Morgan County. Analysis of E. coli isolates indicated feral pigs carry more virulent strains compared to cattle and farm pigs. Water samples are being tested to analyze the transport of pathogens from feral pig feces to surface waters.
Effects of renewal pattern of recycled nutrient solution on the ion balance i...gugabione
Ion imbalance in recycled nutrient solutions is caused by selective ion uptake of plants, which occurs at different
rates in different growth stages. The objectives of this study were to investigate the ion balances in both recycled nutrient
solutions and rockwool media using different renewal patterns for the nutrient solutions, and to analyze the subsequent effects
on uptake of water and nutrients. Over 12 weeks of paprika cultivation, two different renewal patterns (week units) of 6-4-2
and 8-2-2 weeks were compared with a constant renewal pattern of 4-4-4 weeks (control). The nutrient solution in the reservoir
tank was constantly maintained at EC 2.5 dS・m
-1
and pH 5.5-6.5. The changes in the ion balance with the 4-4-4 week pattern
were smaller than those with the other treatments. In the early growth stage, however, the ion balances similarly changed
among all treatments. Greater changes were subsequently observed for the 6-4-2 week pattern. Although fruit yield and shoot
fresh weight of paprika were the lowest with 6-4-2 renewal pattern, no significant differences were observed. Our results indicate
that renewal intervals can be extended in consideration of growth stage for more efficient and practical operations in closed
soilless cultures.
This document summarizes a research project on climate change mitigation and adaptation in dairy production systems in the Great Lakes region. It involves researchers from 13 institutions studying ways to reduce greenhouse gas emissions and adapt dairy farming to climate change through changes to cow feeding, manure management, and crop production. They are evaluating these practices using models and field trials to identify the most effective strategies to lower emissions and increase farm profitability. A key outcome is education of students through the transformation of a Milwaukee high school into one focused on agricultural sciences.
This document summarizes research on the physicochemical controls of transport of veterinary pharmaceuticals and hormones to surface waters. The research examined how sorption to soil phases and facilitated transport by fine particles can influence the fate and transport of antibiotics in the environment. Completed and ongoing work is described that examines the long-term sorption kinetics of lincomycin to biochars under varying conditions, as well as the potential for biochar particles to facilitate the transport of antibiotics through saturated porous media. The research aims to better understand how biochar amendments may reduce the transport and bioavailability of antibiotics in soil.
Invitro Assessment of the Growth and Biomass Level of Chlorella in Textile an...ijtsrd
Chlorella has the capacity to sustain in both fresh water and wastewater. The present study deals with a comparison of the growth and yield of Chlorella in fresh water and textile and tannery wastewaters. The wastewaters used in the study were collected from textile and tannery dyeing units. The wastewater was diluted with tap water in different dilutions 60 , 70 and 80 . Higher dilution yields better biomass parallel to tap water. The result of present study confirms that Chlorella can sustain in almost all wastewaters but gives the maximum yield in textile wastewater. P. S. Subashini | Dr. P. Rajiv "Invitro Assessment of the Growth and Biomass Level of Chlorella in Textile and Tannery Wastewater" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-3 | Issue-2 , February 2019, URL: https://www.ijtsrd.com/papers/ijtsrd20291.pdf
Paper URL: https://www.ijtsrd.com/biological-science/biotechnology/20291/invitro-assessment-of-the-growth-and-biomass-level-of-chlorella-in-textile-and-tannery-wastewater/p-s-subashini
At present our country is facing various problems, among that energy crisis has become more serious in next coming years. Both energy crisis and pollution problems could be controlled by adopting an alternative method of biogas production form waste products. Food waste is the best alternative for biogas production in a community level biogas plant. Hence in the present study, an attempt has been made to study the rate of biogas production in a lab scale biogas digester model for the efficient conversion of the food waste (starch –rich materials) generated from PRIST University Campus. The biogas production depends on the maximum biogas yield, the concentration of volatile solids of the input, the density of the effluent, the density of the biogas and the reaction rate constant, which are all substrate - or process - specific. The experiments were carried out for 40 days and the rate of gas production was measured by water displacement method. The pH value of the cow dung and food waste was initially measured and adjusted to nearer to neutral and gradually increased to acidic and again it got stabilised to the neutral pH which favoured the production of biogas. The percentage of total solids was 69.86, 93.56 and 25.67 for cow dung, food waste and digested slurry respectively. The percentage of volatile solids was 52.5, 86.3 and 18.9 for cow dung, food waste and digested slurry respectively. The percentage of volatile fatty acid was 285, 356 and 365 for cow dung, food waste and digested slurry respectively. Observations on daily basis were made on the constituent of biogas, pH, volume and rate of biogas production. The rate of biogas production continuously increased as days progressed and there was maximum yield in biogas after 20 days. Thus continuous feeding helps in daily biogas production and can be used at a small as well as larger scale to manage the organic waste and energy production for various applications.
Anaerobic Co-Digestion of Cassava Waste Water and Abdominal Cow Dung under Ch...IJCMESJOURNAL
Anaerobic co-digestion of cassava waste water (CWW) and abdominal cow dung (ACD)in different proportions was studied in five treatments under changing meteorological conditions. The five treatment cases T1: 100% CWW; T2: 100% ACD; T3: 90%CWW +10%ACD; T4:70%CWW+30%ACD; T5: 50%CWW+50%ACD were digested under anaerobic conditions in model batch, metallic bio digesters of same working volume (32.0 liters) for 30 days retention period. Results indicated that T2 system flamed on the 20th day, T5 on the 20th day while T1, T4 and T3 systems didn’t flame. T1 had cumulative gas yield of 12.7 liters; T2 had 28.85 liters; T3 had 12.5 liters,T4 had 11.1 liters while T5 had cumulative gas yield of 15.8 liters per 24kg mass of slurry. T2had 91.20% methane; while T5 produced 92.999% methane. Daily biogas yields were modeled as functions of meteorological parameters. Results indicated that many parameters showed good correlations with ambient temperature.
Effect of co digestion on anaerobic digestion of cattle slurry with maize cob...Alexander Decker
1) Researchers investigated the effect of co-digesting cattle slurry and maize cob at different ratios (3:1, 1:1, 1:3 cattle slurry to maize cob) on biogas and methane production under mesophilic temperature (37°C).
2) Co-digesting cattle slurry and maize cob at a 3:1 ratio produced the highest biogas yield of 453.38 lN/kg oDM and methane yield of 334.18 lNCH4/kg oDM.
3) Methane concentrations ranged from 73.71% to 77.55% depending on the ratio, with the highest concentration obtained at a 1:1 ratio of cattle sl
Agricultural potential of biosolids generated from dewatering of faecal sludg...Alexander Decker
The document summarizes a study that evaluated the agricultural potential of biosolids produced from dewatering faecal sludge on drying beds in Ghana. Various filter media and loading rates of faecal sludge were tested. Nutrients like carbon, nitrogen, phosphorus and potassium were within ranges that would support agricultural use. Heavy metal concentrations in the biosolids were very low and below limits for use in developing countries. The results indicate the biosolids have nutrient value and low risk of heavy metal contamination, suggesting potential for use as fertilizer in agriculture.
The document summarizes a research study that exposed mice to the gaseous fraction of emissions from cashew nut shell combustion. Key findings include:
1) Exposure to the gaseous fraction resulted in changes to respiratory system mechanics, oxidative stress levels, and histopathological lung changes in mice.
2) While filters are used to remove particulate matter from biomass combustion emissions, the study demonstrates that the gaseous fraction still causes harmful health effects and requires attention.
3) The study analyzed the combustion process and chemical composition of the gaseous fraction to better understand its toxic effects on the respiratory system.
Comparison of kinetic models for biogas production rate from saw dusteSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Effect of different bulking materials and earthworms species on bioremediatio...Alexander Decker
This study investigated the effect of different bulking materials (cow dung, sheep manure, garden soil) and earthworm species (Eudrilus eugeniae and Eisenia foetida) on the bioremediation of municipal sewage sludge. The results showed that interactions between worm species and bulking materials significantly affected moisture content, EC, and chloride levels but not pH or organic carbon. Organic carbon, EC, and chloride levels generally decreased from the initial to final stages of vermiremediation. The combination of cow dung and Eudrilus eugeniae led to the lowest levels of EC, organic carbon, and chloride, indicating it was the most effective treatment for bioremedi
Environmental Engineering for Enhancing the Suitability of a Microalga for En...IRJET Journal
This document discusses research conducted on the microalga Chlorella vulgaris to study the effects of varying pH and salinity on its growth, biomass production, and lipid content. The researchers found that growth and biomass were highest at pH 7, while lipid content increased with higher salinity up to 0.25M, beyond which growth decreased. The goal was to optimize environmental conditions to enhance the suitability of C. vulgaris for renewable energy production through biomass and lipid accumulation.
This document summarizes a study that analyzed changes in bacterial and archaeal communities during thermophilic composting of cattle manure using PhyloChip microarray technology. Samples were collected from different areas of a compost pile based on age and temperature. Total DNA was extracted from the samples and the 16S rRNA gene was amplified and hybridized to a PhyloChip array. Statistical analysis showed differences in microbial populations between raw manure samples and compost samples. During composting, archaeal phyla Thaumarchaeota and Thermoprotei and bacterial phyla Actinobacteria and Firmicutes increased in diversity. Ammonia-oxidizing and methanogenic microbes increased under thermophilic conditions. The
This document evaluates the effect of 15 kGy gamma radiation on eight different agro-waste materials for cultivation of oyster mushrooms (Pleurotus eous strain P-31). Corn cobs performed the best overall with the fastest mycelia colonization rate, shortest colonization time, no contamination, and highest density. It also had the largest cap diameter, longest stipe length, most primordia and fruit bodies, largest mushroom size, and shortest time between flushes. Corn cobs achieved the highest biological efficiency of 63% and mushroom yield of 377g. The gamma irradiated substrates significantly influenced mushroom growth and yield. Gamma irradiation is concluded to be a potential alternative method for pretreating lignocell
This document provides information on sediment composition, sediment contamination, remediation technologies for contaminated sediments, and their applications and trends. It discusses the components and contaminants commonly found in sediments. The key contaminant characteristics affecting treatment are described. Major remediation technologies discussed include dredging, capping, solidification, biostimulation, bioaugmentation, and monitored natural recovery. Emerging integrated technologies like in situ phase inversion emulsification and biological reductive dechlorination are introduced. Benchmark comparisons of laboratory and field studies on contaminated sediment remediation are provided.
Characterization of organic compounds from biosolids of Buenos Aires City, Silvana Torri
This study characterized the organic compounds in biosolids from Buenos Aires, Argentina. Different solvents were evaluated for ultrasound-assisted extraction (UAE) and a hexane:acetone mixture provided the highest extractability. The organic compounds identified included fatty acids, n-alkanes, and steroids. Persistent organic pollutants were below detection limits. The recalcitrant organic fraction reported previously is mainly due to stable sterols in the biosolids.
World reserves of petroleum are rapidly depleting, in recent years methane from biogas has emerged as important alternative resource for fuel and chemicals production and has generated a great deal of research interest in methane production. Lignocellulosic biomass is the most abundant organic raw material in the world. Production of methane as second-generation biofuels from renewable lignocellulosic resources may improve energy availability, decrease air pollution and diminish atmospheric CO2 emissions. The use of wheat straw does not affect the food supply; thus, wheat straw was analyzed as a raw material for second-generation biofuels production. The aim of this paper is to present a thermodynamic analysis for methane production from lignin-based aromatics (vanillin) with the method of Gibbs free energy minimization using the Aspen Plus® simulator. The analysis was carried out using the interval 350-1500 K, feeding a H2O/Vanillin ratio (WVR) of 0.6 to 5.0, 1 atm. The results showed that the vanillin conversion was almost completed, except at the highest vanillin feed concentration, in which the conversion was of 65%. Methane yields from 2 to 4 mol CH4/mol vanillin were obtained at high and low vanillin feed concentrations, respectively, when operating at low temperature.
Using next generation sequencing to describe epiphytic microbiota associated ...Agriculture Journal IJOEAR
Abstract— Its seems likely that agricultural management as diverse as certified organic and conventional IPM practices would impact the microbiota associated with crop surfaces differently. We sampled organic and conventionally managed apples at multiple time-points in a growing season and characterized the bacterial taxa associated with replicates of each treatment type. Surprisingly, no evidence of significant differences persisting across multiple time-points was observed. Significant differential abundance of certain taxa was documented but when it was, it was primarily associated with a single time-point making it difficult to understand if these observations resulted from an environmental or a treatment effect. Principal component analyses demonstrated that sampling time-point explained more of the differences between bacterial communities than treatment. Description of dominant shared bacterial families for both organic and conventional samples included Oxalobacteraceae, Pseudomonadaceae, Sphingomonadaceae and Enterobacteriaceae.
Effect of wheat straw components on the yield of pleurotus eousDr. siddhant
The document presents research on the effect of different components of wheat straw (leaves, leaf sheaths, and stems of various sizes) on mushroom yield when grown on Pleurotus eous. Small and large stem pieces (1.0-1.7cm) produced the highest yields of 341-336 grams respectively, with a biological efficiency of 67.2-68.2%. Fine leaves and leaf sheaths (0.2cm) yielded the least at 218 grams with 43.6% efficiency due to having less nutrients and being more susceptible to contamination. Overall, stems were found to be the best wheat straw component for cultivating P. eous mushrooms.
Bioremediating Effect of Glomus Hoi and Pseudomonas Aeruginosa on the Organic...IJEAB
This study analyzed the degrading effect of Glomus hoi and Pseudomonas aeruginosa on the organic content and heavy metals of oil refinery effluent polluted soil using Amaranthus cruentus as the test plant. This study was carried out to determine if agricultural activities can be improved using any or both of the micoorganisms. Eight different treatment layouts were used with three replicates for each level of pollution in the treatment layout. Ninety six (96) pots, each containing three kilograms of soil from both sterilized and unsterilized soil were used for the study. Fifty (50) grams of soil inoculum from propagated Arbuscular mycorrhiza was inoculated to a set of twenty four (24) experimental pots containing both sterilized and unsterilized soil before A. cruentus seedlings were transplanted to them. Another set of twenty four (24) pots containing both sterilized and unsterilized soil were injected with thirty (30) mL of P. aeruginosa inoculum solution before transplanting A. cruentus seedlings to them. The third set of twenty four (24) pots received dual inoculation of both fifty (50) grams of soil inoculum containing G. hoi and thirty (30) mL of P. aeruginosa inoculum solution before A. cruentus were transplanted to them. The residual twenty four (24) pots served as the control. Thereafter, pot preparation was arranged in the screenhouse in a randomized block design. The A. cruentus seedlings were raised in nursery for a period of two weeks before they were transplanted to the pots, seedlings were left for 3 days to overcome transplanting shock before contaminating the soil with refinery effluent at various concentrations of 0%, 2%, 4% and 6% v/w. The seedlings were allowed to grow for eight weeks before the termination of the experiment. The pre planting analysis of soil showed that heavy metals analyses (zinc and iron) of sterilized soil had a lower concentration to the unsterilized. The soil pH ranged from 6.3 to 6.8. It also revealed that organic matter and organic carbon content ranged from 0.8% to 1.3% and 0.4% to 1.7%. However, after the experiment, it was discovered in this study that treatments without any microorganism inoculation in sterilized and unsterilized soil had a higher level of % organic carbon and % organic matter content compared to the other treatments that were inoculated with one or two micro-organisms across all the levels of effluent concentration. Heavy metals of soil in all the soil samples were found to increase as the petrochemical effluent increased in concentration. The results obtained were analyzed using Duncan Multiple Range Test (DMRT) and other descriptive statistics. This study opined that the combined use of G. hoi and P. aeruginosa was more effective in improving the organic contentand the reduce heavy metals of oil refinery effluent polluted soil than when either is used singly.
Anaerobicaly - Composted Environmental Wastes as Organic Fertilizer and Ident...Oyeniyi Samuel
This document summarizes a study that anaerobically composted sawdust, wood shavings, and poultry manure to produce organic fertilizer. The compost was high in nutrients like organic carbon, nitrogen, phosphorus, and minerals. Nine fungi species were isolated from the compost, including Aspergillus candidus, Aspergillus fumigatus, Penicillium aethiopicum, and Fusarium species. These fungi helped decompose the lignified materials during the composting process. The compost produced was found to be rich in organic matter and nutrients, making it a suitable supplement to inorganic fertilizers for sustainable crop production.
This study evaluated the presence of pathogenic bacteria in fecal samples collected from feral pigs in five counties in Georgia. Quantitative PCR screening detected Brucella suis in 25% of samples and E. coli O157:H7 in 5.5% of samples, but did not detect Campylobacter jejuni. The majority of pigs carrying pathogens came from Morgan County. Analysis of E. coli isolates indicated feral pigs carry more virulent strains compared to cattle and farm pigs. Water samples are being tested to analyze the transport of pathogens from feral pig feces to surface waters.
Effects of renewal pattern of recycled nutrient solution on the ion balance i...gugabione
Ion imbalance in recycled nutrient solutions is caused by selective ion uptake of plants, which occurs at different
rates in different growth stages. The objectives of this study were to investigate the ion balances in both recycled nutrient
solutions and rockwool media using different renewal patterns for the nutrient solutions, and to analyze the subsequent effects
on uptake of water and nutrients. Over 12 weeks of paprika cultivation, two different renewal patterns (week units) of 6-4-2
and 8-2-2 weeks were compared with a constant renewal pattern of 4-4-4 weeks (control). The nutrient solution in the reservoir
tank was constantly maintained at EC 2.5 dS・m
-1
and pH 5.5-6.5. The changes in the ion balance with the 4-4-4 week pattern
were smaller than those with the other treatments. In the early growth stage, however, the ion balances similarly changed
among all treatments. Greater changes were subsequently observed for the 6-4-2 week pattern. Although fruit yield and shoot
fresh weight of paprika were the lowest with 6-4-2 renewal pattern, no significant differences were observed. Our results indicate
that renewal intervals can be extended in consideration of growth stage for more efficient and practical operations in closed
soilless cultures.
This document summarizes a research project on climate change mitigation and adaptation in dairy production systems in the Great Lakes region. It involves researchers from 13 institutions studying ways to reduce greenhouse gas emissions and adapt dairy farming to climate change through changes to cow feeding, manure management, and crop production. They are evaluating these practices using models and field trials to identify the most effective strategies to lower emissions and increase farm profitability. A key outcome is education of students through the transformation of a Milwaukee high school into one focused on agricultural sciences.
This document summarizes research on the physicochemical controls of transport of veterinary pharmaceuticals and hormones to surface waters. The research examined how sorption to soil phases and facilitated transport by fine particles can influence the fate and transport of antibiotics in the environment. Completed and ongoing work is described that examines the long-term sorption kinetics of lincomycin to biochars under varying conditions, as well as the potential for biochar particles to facilitate the transport of antibiotics through saturated porous media. The research aims to better understand how biochar amendments may reduce the transport and bioavailability of antibiotics in soil.
Invitro Assessment of the Growth and Biomass Level of Chlorella in Textile an...ijtsrd
Chlorella has the capacity to sustain in both fresh water and wastewater. The present study deals with a comparison of the growth and yield of Chlorella in fresh water and textile and tannery wastewaters. The wastewaters used in the study were collected from textile and tannery dyeing units. The wastewater was diluted with tap water in different dilutions 60 , 70 and 80 . Higher dilution yields better biomass parallel to tap water. The result of present study confirms that Chlorella can sustain in almost all wastewaters but gives the maximum yield in textile wastewater. P. S. Subashini | Dr. P. Rajiv "Invitro Assessment of the Growth and Biomass Level of Chlorella in Textile and Tannery Wastewater" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-3 | Issue-2 , February 2019, URL: https://www.ijtsrd.com/papers/ijtsrd20291.pdf
Paper URL: https://www.ijtsrd.com/biological-science/biotechnology/20291/invitro-assessment-of-the-growth-and-biomass-level-of-chlorella-in-textile-and-tannery-wastewater/p-s-subashini
At present our country is facing various problems, among that energy crisis has become more serious in next coming years. Both energy crisis and pollution problems could be controlled by adopting an alternative method of biogas production form waste products. Food waste is the best alternative for biogas production in a community level biogas plant. Hence in the present study, an attempt has been made to study the rate of biogas production in a lab scale biogas digester model for the efficient conversion of the food waste (starch –rich materials) generated from PRIST University Campus. The biogas production depends on the maximum biogas yield, the concentration of volatile solids of the input, the density of the effluent, the density of the biogas and the reaction rate constant, which are all substrate - or process - specific. The experiments were carried out for 40 days and the rate of gas production was measured by water displacement method. The pH value of the cow dung and food waste was initially measured and adjusted to nearer to neutral and gradually increased to acidic and again it got stabilised to the neutral pH which favoured the production of biogas. The percentage of total solids was 69.86, 93.56 and 25.67 for cow dung, food waste and digested slurry respectively. The percentage of volatile solids was 52.5, 86.3 and 18.9 for cow dung, food waste and digested slurry respectively. The percentage of volatile fatty acid was 285, 356 and 365 for cow dung, food waste and digested slurry respectively. Observations on daily basis were made on the constituent of biogas, pH, volume and rate of biogas production. The rate of biogas production continuously increased as days progressed and there was maximum yield in biogas after 20 days. Thus continuous feeding helps in daily biogas production and can be used at a small as well as larger scale to manage the organic waste and energy production for various applications.
Anaerobic Co-Digestion of Cassava Waste Water and Abdominal Cow Dung under Ch...IJCMESJOURNAL
Anaerobic co-digestion of cassava waste water (CWW) and abdominal cow dung (ACD)in different proportions was studied in five treatments under changing meteorological conditions. The five treatment cases T1: 100% CWW; T2: 100% ACD; T3: 90%CWW +10%ACD; T4:70%CWW+30%ACD; T5: 50%CWW+50%ACD were digested under anaerobic conditions in model batch, metallic bio digesters of same working volume (32.0 liters) for 30 days retention period. Results indicated that T2 system flamed on the 20th day, T5 on the 20th day while T1, T4 and T3 systems didn’t flame. T1 had cumulative gas yield of 12.7 liters; T2 had 28.85 liters; T3 had 12.5 liters,T4 had 11.1 liters while T5 had cumulative gas yield of 15.8 liters per 24kg mass of slurry. T2had 91.20% methane; while T5 produced 92.999% methane. Daily biogas yields were modeled as functions of meteorological parameters. Results indicated that many parameters showed good correlations with ambient temperature.
International Journal of Engineering and Science Invention (IJESI) inventionjournals
International Journal of Engineering and Science Invention (IJESI) is an international journal intended for professionals and researchers in all fields of computer science and electronics. IJESI publishes research articles and reviews within the whole field Engineering Science and Technology, new teaching methods, assessment, validation and the impact of new technologies and it will continue to provide information on the latest trends and developments in this ever-expanding subject. The publications of papers are selected through double peer reviewed to ensure originality, relevance, and readability. The articles published in our journal can be accessed online
Development of integrated bioremediation and anaerobic digestion process usingIAEME Publication
This document discusses a study on the development of an integrated bioremediation and anaerobic digestion process using microalgae. Specifically, it examines using the microalgae Chlorella pyrenoidosa to treat biogas digester wastewater. The study finds that C. pyrenoidosa is able to grow well in biogas wastewater, removing up to 92.8% of nitrate nitrogen. The treated wastewater can then be used to support anaerobic digestion of the algal biomass to produce biogas. Co-digesting the microalgae with cow dung achieved higher biogas yields than digesting cow dung alone. Overall, the integrated process effectively treats biogas
IRJET- Enhancement of Biogas Production by Co-Digestion of Fruit and Vegetabl...IRJET Journal
This document discusses a study on enhancing biogas production through co-digestion of fruit and vegetable waste with cow dung. Four mixtures of fruit, vegetable, and cow waste were prepared in different ratios and subjected to anaerobic digestion. The biogas production from each mixture was measured and modeled using logistic and modified Gompertz kinetic models. The results showed that a ratio of 0.5 parts fruit waste, 1.5 parts vegetable waste, and 1 part cow waste produced the highest amount of biogas and fit best to the modified Gompertz model. Characterization of the waste mixtures found total solid and volatile solid contents ranged from 74-75% with C/N ratios between 5-9.
Biogas Production Enhancement from Mixed Animal Wastes at Mesophilic Anaerobi...IJERA Editor
In this work, the effect of mixing ratio of cattle dung (CD) and poultry droppings (PD) on biogas generation was
determined. Mixtures of various CD: PD ratios (100% : 0%; 50% : 50%; 60% : 40%; 80% : 20% and 0% :
100%) were prepared, analyzed and then aerobically digested for a period of 40 days. For each mixture,
fermentation was carried out in a 20 L capacity digester. Results showed that biogas was obtained from the
digestion of CD and PD alone, showing the biogas from CD was several times larger than that from PD.
Furthermore, the resulted biogas yields from mixtures were found a function of the CD : PD ratio, the yield from
the ratio 80 : 20 was the maximum. Biogas yields from the prepared mixtures were found and arranged from
larger to lower in the form of (CD : PD) ratios as follow: 80% : 20%; 100% : 0.0%; 60% : 40%; 0.0% :
100%;50% : 50%. Addition of CD to PD enhances the PD production of biogas, while addition of a small
portion of PD to CD gave the maximum yield, a result not determined in literature. In other hand, larger
additions of PD to CD reduced the biogas yield. The effect of pH was also determined and found better around
7.0. These results are in agreement with research work in literature.
Impact of Improved Aeration on Decomposition Rate of Enriched Compostijtsrd
Agricultural activities tend to generate a substantial volume of animal and crop residues. Composting is the most economical and ecologically sustainable option to manage farmyard waste. However, it takes approximately three months to complete decomposition and contains lower plant nutrient percentages than inorganic fertilisers. This study aimed to reduce the decomposition time and improve the nutrient content of compost. Aerobic decomposition was enhanced by aeration inside the pile using a blower with 0.5 l min kg airflow. Paddy straw, poultry manure, goat manure, cattle manure and paddy husk ash were mixed in 3 1 1 1 1 ratio respectively as the raw materials and 3 of Eppawala Rock Phosphate was added to the mixture in weight basis. Six piles 150 X 100 X 80 cm were prepared, and three piles were aerated for six hours per day while other three piles were left to decompose under the ambient condition as the control. According to the results, aerated and control piles took 35 days and 65 days to complete the decomposition. Total N, available P, exchangeable K, C N ratio, pH, EC and CEC were analysed in compost samples from aerated after 35 days and controls, and the results were, 20.5 g kg 1, 1.8 g kg 1, 10.4 g kg 1, 7, 8.8, 4.3 mS cm 1, 19.3 cmol kg 1 and 17.8 g kg 1, 1.5 g kg 1, 9.9 g kg 1, 8.5, 8.8, 3.64 mS cm 1, 21.3 cmol kg 1 respectively. Data were analysed using SAS 9.0 software with a 95 confidence interval. The results revealed a significant increment in total N, exchangeable K, C N ratio, EC and CEC in aerated piles compared to controls. And the nutrient composition of both methods was significantly higher than the commercial compost. Therefore, it can be concluded that decomposition time can be effectively reduced and the nutrient level can be increased by artificial aeration and nutrient enrichment, respectively. However, further studies are recommended to study the economic feasibility. D. M. S. H. Dissanayaka | V. P. T. Dhananjaya | E. J. Kosgollegedara | S. Karthigayini "Impact of Improved Aeration on Decomposition Rate of Enriched Compost" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-5 | Issue-2 , February 2021, URL: https://www.ijtsrd.com/papers/ijtsrd38557.pdf Paper Url: https://www.ijtsrd.com/engineering/agricultural-engineering/38557/impact-of-improved-aeration-on-decomposition-rate-of-enriched-compost/d-m-s-h-dissanayaka
Increasing Water Temperature in a Bio-Geyser during Ensiling of Berseem by In...CrimsonpublishersMCDA
A model silo cum bio geyser system was developed in The University of Agriculture Peshawar to utilize the biomass. In this silo, impact of biomass combination (Berseem and Mott grass) and fermenting agent (rumen liquor) on the amount of heat loss during ensiling. The experiments were laid out in completely randomized design having four treatments and three replications with twelve observations. In the silo water was stored in a Copper pipe located in the middle of the silo while silage was prepared around the pipe. During the fermentation process heat evolved was transferred to the pipe heating the water. Two biomass combination (Berseem only and Berseem 50% + Mott grass 50%) and two levels of fermenting agent (rumen liquor 1% and rumen liquor 0% as control) were used. Four treatments involved in this experiment were; 1. Berseem + rumen liquor, 2. Berseem + Mott grass + rumen liquor, 3. Berseem + control and 4. Berseem + Mott grass + control. Biomass combination and fermenting agent showed a significant effect on water temperature. It was also observed that the maximum temperature of water was recorded 480C in treatment 4 while minimum temperatures of 430C in treatment 3 and 390C in treatment 1 respectively. It was concluded that the highest loss of heat during ensiling was obtained during the fermentation process of 5 days.
This document summarizes a study that investigated the effect of different culture media and carbon sources on the biomass productivity and oil content of four algal species. The study found that Bristol's medium resulted in the highest biomass and oil contents overall, followed by water extract of dairy waste. Among carbon sources, calcium carbonate enhanced biomass most while sodium bicarbonate increased oil content the most. The algal species Sirogonium sticticum produced the highest biomass and oil content regardless of media or carbon source. The study concluded that water extract of dairy waste could be a suitable and cost-effective medium for commercial microalgae cultivation.
IRJET - Evaluation of Biogas Production from Fishwaste with Three Other Co-Di...IRJET Journal
This document evaluates biogas production from fish waste using different co-digesters, including baggase, paper waste, and dry leaves. An experiment was conducted with three containers of fish waste mixed in equal proportion with cow dung and one of the three co-digesters. The results found that paper waste produced the maximum biogas yield of 188 ml/kg. Further experiments determined that a mixture of 8kg fish waste, 2kg paper waste, and 2kg cow dung produced the highest yield of 286 ml/kg. The study concludes that paper waste is the most effective co-digester for maximizing biogas production from fish waste.
This document summarizes a study on using Lemna minor (duckweed) to treat wastewater in bio-treatment ponds in Pakistan. The study evaluated the effectiveness of duckweed in removing heavy metals from wastewater ponds constructed at the National Agricultural Research Center. Analysis found that duckweed accumulated higher concentrations of heavy metals like zinc, lead, nickel, manganese, and iron compared to the wastewater. The treated wastewater met parameters for reuse in aquaculture and agriculture, and the plants around the ponds were healthy. The study demonstrated that bio-treatment ponds could be an effective wastewater treatment approach in Pakistan.
International Journal of Engineering and Science Invention (IJESI) is an international journal intended for professionals and researchers in all fields of computer science and electronics. IJESI publishes research articles and reviews within the whole field Engineering Science and Technology, new teaching methods, assessment, validation and the impact of new technologies and it will continue to provide information on the latest trends and developments in this ever-expanding subject. The publications of papers are selected through double peer reviewed to ensure originality, relevance, and readability. The articles published in our journal can be accessed online.
1) The document describes a study on the anaerobic co-digestion of water hyacinth and poultry litter.
2) Batch experiments were conducted in 300ml digesters at mesophilic temperatures to determine biogas production, total solids, volatile solids, and pH over retention periods of 0-56 days.
3) Kinetic modeling using an integral method revealed that the co-digestion process followed first-order reaction kinetics with a rate constant of 0.026 day-1.
STUDY ON BIO-METHANATION USING POULTRY DROPPING-Abdullah Nasir PulakAbdullah Pulak
This study examined biogas production from poultry droppings through anaerobic digestion with cow dung. Four laboratory reactors were tested with varying ratios of poultry droppings and cow dung. Reactor D2, with 75% poultry droppings and 25% cow dung, produced the highest volatile solid reduction (53%), specific gas yield (0.72 l/g), and methane content (73.2%). Poultry droppings alone were found to be unsuitable due to a low carbon-nitrogen ratio, but mixing with cow dung increased the ratio and improved biogas production. The study suggests anaerobic digestion of poultry droppings mixed with cow dung can effectively produce
Comparative evaluation of qualitative and quantitative biogas production pote...Alexander Decker
The document summarizes a study that evaluated biogas production from oil palm fronds alone and co-digested with cow dung. When oil palm fronds were digested alone, biogas production was slower with a total yield of 116L over 27 days. Co-digesting the fronds with cow dung at a 1:1 ratio optimized biogas production, yielding 187.4L over the same period. Key factors influencing higher production from co-digestion included improved nutrient balance and microbial activity from the cow dung. The study demonstrates that co-digesting available agricultural and animal wastes can provide an environmentally-friendly energy source.
Co-digesting cow dung and food waste at different ratios improved biogas production over mono-digesting the substrates individually. The highest biogas yield of 25595.7 Nml was obtained at a cow dung to food waste ratio of 1:2. Mono-digesting cow dung and food waste individually produced lower biogas volumes of 12847.4 Nml and 110.2 Nml respectively. Co-digesting the substrates led to a 49.8% increase in total biogas production compared to mono-digestion, demonstrating that co-digestion is an effective way to improve biogas yields.
Composition and Toxicity of Biogas Produced from DifferentFe.docxmccormicknadine86
Composition and Toxicity of Biogas Produced from Different
Feedstocks in California
Yin Li,† Christopher P. Alaimo,† Minji Kim,† Norman Y. Kado,§ Joshua Peppers,‡ Jian Xue,†
Chao Wan,† Peter G. Green,† Ruihong Zhang,‡ Bryan M. Jenkins,‡ Christoph F. A. Vogel,§
Stefan Wuertz,∥ Thomas M. Young,† and Michael J. Kleeman*,†
†Department of Civil and Environmental Engineering, ‡Department of Biological and Agricultural Engineering, and §Department of
Environmental Toxicology and Center for Health and the Environment, University of California − Davis, Davis, California 95616,
United States
∥Singapore Center for Environmental Life Sciences Engineering, Nanyang Technical University, Singapore 637551
*S Supporting Information
ABSTRACT: Biogas is a renewable energy source composed
of methane, carbon dioxide, and other trace compounds
produced from anaerobic digestion of organic matter. A
variety of feedstocks can be combined with different digestion
techniques that each yields biogas with different trace
compositions. California is expanding biogas production
systems to help meet greenhouse gas reduction goals. Here,
we report the composition of six California biogas streams
from three different feedstocks (dairy manure, food waste, and
municipal solid waste). The chemical and biological
composition of raw biogas is reported, and the toxicity of
combusted biogas is tested under fresh and photochemically
aged conditions. Results show that municipal waste biogas
contained elevated levels of chemicals associated with volatile chemical products such as aromatic hydrocarbons, siloxanes, and
certain halogenated hydrocarbons. Food waste biogas contained elevated levels of sulfur-containing compounds including
hydrogen sulfide, mercaptans, and sulfur dioxide. Biogas produced from dairy manure generally had lower concentrations of
trace chemicals, but the combustion products had slightly higher toxicity response compared to the other feedstocks.
Atmospheric aging performed in a photochemical smog chamber did not strongly change the toxicity (oxidative capacity or
mutagenicity) of biogas combustion exhaust.
1. INTRODUCTION
Biogas is a renewable fuel produced from the anaerobic
digestion of organic feedstocks including municipal waste, farm
waste, food waste, and energy crops. Raw biogas typically
consists of methane (50−75%), carbon dioxide (25−50%),
and smaller amounts of nitrogen (2−8%). Trace levels of
hydrogen sulfide, ammonia, hydrogen, and various volatile
organic compounds are also present in biogas depending on
the feedstock.1 Life cycle assessment studies have shown that
deploying biogas technologies can effectively reduce green-
house gas (GHG) emissions and, therefore, reduce the climate
impact of energy consumption.2−4 Biogas production and
utilization practices also help diversify energy systems while
simultaneously promoting sustainable waste management
practices.1,5 California is promoting biogas utilization by
mandating the low carbon fuels, ...
Anaerobic Digestion of Biodegradable Organics in Municipal Solid Wastes in Na...IRJET Journal
This document discusses anaerobic digestion of biodegradable organics in municipal solid waste in Nashik City, India. It summarizes that anaerobic digestion uses bacteria in an oxygen-free environment to decompose waste into carbon dioxide and methane, which can be used to generate biogas and electricity. The document outlines the methodology, including using food waste collected from the city and monitoring pH and temperature during digestion. Results found that anaerobic digestion reduced biochemical oxygen demand and chemical oxygen demand by 35-55% and pH was maintained between 7.1-7.9. The conclusion is that anaerobic digestion is an effective method for treating food waste to produce biogas while controlling environmental impacts.
International Journal of Computational Engineering Research(IJCER)ijceronline
International Journal of Computational Engineering Research(IJCER) is an intentional online Journal in English monthly publishing journal. This Journal publish original research work that contributes significantly to further the scientific knowledge in engineering and Technology.
Biogas Production from Water Hyacinth and Cow dungijtsrd
In the quest for sustainable and eco friendly energy solutions, renewable energy biogas technology stands out as a promising option, offering zero waste energy generation. River water hyacinths, known for their rapid and abundant growth, hold great potential in this domain. Rich in cellulose, nitrogen, essential nutrients, and fermentable components, water hyacinth leaves present an ideal source for biogas fuel production. Notably, their high hemicellulose content allows for efficient biogas generation. This study focuses on harnessing the biogas potential of water hyacinths readily available in river ecosystems. The experimental setup involved employing water hyacinth, cow dung, and water at various ratios using the batch fermentation technique. Daily monitoring of biogas production was conducted throughout the 60 day degradation process until the desired gas production levels were achieved, alongside effective degradation of the biomass. An essential factor explored in this study was the Carbon to Nitrogen C N ratio, recognized as a critical determinant for successful biogas production. The research findings revealed that a C N ratio of 30.75 proved to be optimal for this specific experiment. This research contributes valuable insights into the potential of renewable biogas technology, highlighting the significance of utilizing water hyacinths as a viable and sustainable energy resource, while also offering a greener approach to address environmental challenges. Srinivas Kasulla | S J Malik | Gaurav Kathpal | Anjani Yadav "Biogas Production from Water Hyacinth and Cow dung" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-7 | Issue-4, August 2023, URL: https://www.ijtsrd.com/papers/ijtsrd59703.pdf Paper Url:https://www.ijtsrd.com/other-scientific-research-area/enviormental-science/59703/biogas-production-from-water-hyacinth-and-cow-dung/srinivas-kasulla
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Evaluation of Biogas Production from the Digestion of Swine Dung, Plantain Peel and Fluted Pumpkin Stem
1. International Journal of Civil, Mechanical and Energy Science (IJCMES) [Vol-5, Issue-2, Mar-Apr, 2019]
https://dx.doi.org/10.22161/ijcmes.5.2.3 ISSN: 2455-5304
www.ijcmes.com Page | 14
Evaluation of Biogas Production from the
Digestion of Swine Dung, Plantain Peel and Fluted
Pumpkin Stem
Cordelia Nnennaya Mama*, Alamba Chinemerem Grace, Chukwu Igwe
Chukwu, Maduka Chidinma Hephzibah
Department of Civil Engineering, University of Nigeria, Nsukka, Enugu State, Nigeria
*Corresponding Author: cordelia.mama@unn.edu.ng
Abstract— This study centered on biogas production from
locally available animal and kitchen wastes: swine dung
(SD), plantain peel (PP) and fluted pumpkin stem (PS)
using five 32-Litres metallic prototype digesters. The
anaerobic digestion was in the ratio of 3:1 of water to
waste for all the samples as follows: Sample A was
100%SD, Sample B; 100% PP, Sample C; 100% PS,
Sample D; 50%SD+50%PP and Sample E; 40% SD+30%
PP+30% PS. The retention time was 30 days and
parameters like pH, pressure, daily biogas production,
ambient and slurry temperatures alongside the physico-
chemical properties of wastes were monitored. The
cumulative gas production yield was 11.5L, 35.1L, 39.5L,
46.9L, 59.3L for Sample A, Sample B, Sample C, Sample D
and Sample E respectively. The flammable time was 15th
,
5th
, 25th
, 26th
, 2nd
day for sample A, sample B, sample C,
sample D and sample E respectively. The result revealed
that the blend of the 3 substrates i.e. sample E: 40%
SD+30% PP+30% PS gave the highest yield of biogas and
flamed earlier than the other samples while sample A:
100%SD had the lowest yield of biogas. The results also
showed that the sample that had the highest composition of
methane in the biogas produced was Sample D:
50%SD+50%PP with 85.6989% while the lowest
composition of methane was found in Sample C to be
79.0996%. The TS, TVS, BOD and VS were seen to be
consistently reducing showing the level of waste treatment
achieved during the digestion period of 30 days.
Keywords— Swine Dung, PlantainPeel, Fluted Pumpkin
Stem, Daily BiogasProduction, and Evaluation.
Abbreviations: TS=Total Solid, TVS=Total Volatile Solid,
VS=Volatile Solid, BOD=Biochemical Oxygen Demand,
TVC= Total Viable Count
I. INTRODUCTION
It is no doubt that one of the major challenges to human and
environmental health, and economic development of any
society especially in developing countries, is the
continuously increasing production and inefficient
functional Environmental Waste (organic wastes)
Management Policies. Plants and animal wastes are integral
part of biological existence in that the rate and volume of
organic waste production is bound to exist and of course to
increase with the increasing world population. It is very
obvious that due to the current economic disposition of the
country that the campaign for continued and extensive
agricultural production is the gear to the nation’s economic
wheels. In other words, there will be increased agricultural
inputs and of course a corresponding increase of output in
both subsistence and commercial quantities hence,
increasing the waste potential of the agricultural sector
through the stages of production,processing, transportation,
consumption and disposal. Subsequently, generation of
wastes cannot be totally eliminated neither can waste
recycling be achieved completely, thus the need for a more
cost effective and efficient process to optimally reduce the
effects of these wastes while providing a sustainable energy
and eco-rejuvenation through anaerobic digestion.
Literature contains substantial biogas production from
different wastes in the locality. Nwankwo, 2014 did a
research on the digestion of plantain peel (PP) and the
codigestion of plantain peel with swine droppings (PP-SD)
to observe the biogas production ability in a 50litres metal
prototype biodigester. The waste (PP and PP-SD) were
subjected to anaerobic digestion for a period of 44days. The
cumulative biogas yield for the plantain peels alone (PP)
was 80.10dm3 while that of plantain peels mixed with swine
droppings (PP-SD) was 163.30m3. The PP-A commenced
flammable gas production on the 2nd day while, PP-SD
2. International Journal of Civil, Mechanical and Energy Science (IJCMES) [Vol-5, Issue-2, Mar-Apr, 2019]
https://dx.doi.org/10.22161/ijcmes.5.2.3 ISSN: 2455-5304
www.ijcmes.com Page | 15
commenced flammable gas production on the 30th day. The
PP-SD had the highest cumulative gas yield though with a
slow onset of gas flammability. The overall result indicates
that the low gas yield of PP could be significantly enhanced
by blending it with swine droppings. Ezekoye, 2013 carried
out a research on Plantain/almond leaves and pig dung used
as substrates in anaerobic bio digester for producing biogas
by batch operation method within the mesophilic
temperature range of 20.0 to 31.0°C. The study was carried
out to compare biogas production potential from
plantain/almond leaves and pig dung wastes. The
cumulative biogas produced from the plantain/almond
leaves was 220.5L while the cumulative biogas from the pig
dung was 882.5L. The methane component of gas from pig
dung was 70.2% while that for plantain/almond leaves with
algae was 72.7%. The biogas from the almond/plantain
leaves became combustible on sixteenth day while the
biogas from the pig dung was combustible on fourteenth
day. Results showed that pig dung produced more biogas
than the almond/plantain leaves within the same
period.Ofili et al., 2010 researched on the quantity of biogas
yield from anaerobic digestion of rabbit waste and swine
dung. The same volume of digester was used in this
experiment to accurately compare the volume of the biogas
yield. The maximum volume of biogas produced from the
45 litresdigester used was 8.2 litres and 6.8 litres
respectively for swine dung and rabbit waste. It was
observed that the biogas production from swine dung was
greater than that of rabbit waste. These studies focused on
anaerobic digestion of one substrate and or co-digestion of
only two subtrates. Co- digestion was not extended to more
than two wastes, hence the objective of this study. The
study also looked into the mix of the co-digested wastes for
maximum biogas production.
II. MATERIALS AND METHODS
Swine dung was collected from the Animal Farm, Faculty
of Veterinary Medicine, University of Nigeria, Nsukka.
Plantain Peels and Fluted Pumpkin Stem were collected
from various restaurants in the University of Nigeria,
Nsukka. Five metallic model biodigesters (figure 1), utilized
for the study were each of 32.0L working volume
(fabricated locally at the National Centre for Energy
Research and development, University of Nigeria, Nsukka).
The schematic of the biodigester is shown in figure 2.
Materials such as top loading balance (Camry Emperors
Capacity 50kg/110 Ibs), plastic water troughs, graduated
transparent plastic buckets for measuring daily gas
production, pHep pocket-sized pH meter (Hanna
Instruments), thermometers, pressure gauge, thermoplastic
hose pipes, metallic beehive stand, biogas burner fabricated
locally for checking gas flammability, were used.
Fig.1: Five 32-L Bio digesters Used
SAMPLE PREPARATION
The plantain peels were chopped into small pieces and
allowed to ferment for four days while the pumpkin stems
were also chopped into small pieces and soaked in water for
24hrs. The aim of the chopping into smaller pieces and the
soaking was to soften the substrates so that micro-
organisms involved during the anaerobic digestion
(anaerobic microbes) will have access to them easily for
quick production of biogas and partial degradation since
they are known to be better decomposers of cellulose
(Fulford, 1998)
In carrying out this research, five samples were used. The
digesters with only one sample served as the control while
the digesters with more than one sample served as the
experiment. The contents of the digesters were as follows:
Sample A: Swine dung control i.e. 100% swine
dung
Sample B: Plantain peel control i.e. 100% plantain
peel
Sample C: Fluted pumpkin stem control i.e. 100%
fluted pumpkin stem
Sample D: Swine dung and Plantain Peel i.e. 50%
swine dung and 50% plantain peel
Sample E: Swine dung, plantain peel, and fluted
pumpkin stem i.e. 40% swine dung, 30% plantain peel and
30% fluted pumpkin stem
3. International Journal of Civil, Mechanical and Energy Science (IJCMES) [Vol-5, Issue-2, Mar-Apr, 2019]
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Fig.2: Schematic Diagram of the Biodigester
Fig.3: Chopped Fluted Pumpkin Stem
Fig.4: Chopped Plantain Peels
Fig.5: Bag containing Swine Dung
4. International Journal of Civil, Mechanical and Energy Science (IJCMES) [Vol-5, Issue-2, Mar-Apr, 2019]
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III. EXPERIMENTAL SET-UP
Each of the digesters was charged to 75% of its 32litres
capacity. Therefore, a measurement of the amount of a
particular specimen needed was taken in relation to the
equivalent of 75%. This was done so that there would be
vacuum for the production of biogas.
Capacity of the digester = 32litres which is equivalent to
32kilograms
Charge percentage for each digester = 75/100 * 32kg =
24kg
SAMPLE A: 6kg of swine dung was weighed and charged
with 18kg of water in the ratio of 3:1 of waste to water. The
initial pH was 6.7.
SAMPLE B: 6kg of plantain peel was weighed and charged
with 18kg of water in the ratio of 3:1 of waste to water. The
initial pH was 4.8.
SAMPLE C: The fluted pumpkin stem was sieved using
the field sieve to prevent water from interfering with the
measurement (weight). 6kg of the fluted pumpkin stem was
weighed and charged with 18kg of water in the ratio of 3:1
of waste to water. The initial pH was 6.6.
SAMPLE D: 3kg of swine dung and 3kg of plantain peel
was weighed and charged with 18kg of water in the ratio of
3:1 of waste to water. The initial pH was 5.5.
SAMPLE E: 2.4kg of swine dung + 1.8kg of plantain peel
+ 1.8kg of fluted pumpkin stem was weighed and charged
with 18kg of water in the ratio of 3:1 of waste to water. The
initial pH was 7.0.
Physicochemical and Microbial Analyses
The physical and chemical compositions of the undigested
wastes were determined before the digestion. Ash, moisture,
crude fibre, crude nitrogen, crude fat, crude protein, BOD,
contents were carried out using AOAC method of 2005.
Total Solidsand Volatile Solids were determined using
method adopted by Meynell (1982). Phosphorus, potassium,
energy contents were determined using methods described
in Pearson (1976). TVC was determined using methods
described by Ochei and Kolhatkar (2000). Carbon content
was determined using methods described by Schumacher
(2002). The population of the microbes in each of the
treatment cases was determined at different times (at
charging, flammable, peak of production and end of
digestion), during the period of study to monitor the growth
of the microbes at the various stages. Temperature, pH and
pressure were also monitored.
Gas Analysis
The flammable gas compositions from the five digesters
were analyzed using BACHARACH (PCA2) Gas Analyzer,
made in United States.
Data Analysis
The data obtained for the volume of gas production from
each of the systems were subjected to statistical analysis
using SPSS ver.20 and Microsoft Excel XP 2007.
IV. RESULTS AND DISCUSSION
Table 1 shows the physicochemical properties of undigested wastes.
Table.1: Table of the physicochemical properties on the charging day (Day 0)
PARAMETERS 100% SD 100% PP 100% PS 50% SD+50%PP 40% SD+30% PP
+30% PS
Moisture Content(%) 96.15 88.46 84.62 91.38 90.74
Ash Content (%) 0.40 4.80 7.10 2.00 2.50
Crude Fibre (%) 0.80 3.69 5.29 2.20 3.00
Crude Fat (%) 0.39 0.87 1.26 0.64 0.78
Crude Protein (%) 2.10 1.05 0.96 1.49 1.40
Crude Nitrogen (%) 0.3357 0.1678 0.1540 0.2378 0.2238
Carbon Content (%) 2.87 3.91 4.63 3.43 3.83
Phosphorus (%) 0.6 2.1 1.4 1.3 1.8
Potassium(mm/l) 1.1 1.7 1.2 1.5 1.6
Volatile Solids (%) 2.77 10.36 12.68 7.37 8.60
Total Solids (%) 2.77 12.03 15.11 8.00 9.50
B.O.D(mg/l) 73.6 43.2 40.0 57.6 59.2
Total Viable Count (cfu/ml) 58.33X105 41.67X105 33.33X105 45.83X105 50.00X105
Carbon-Nitrogen Ratio 8.5 23.3 30.1 14.4 17.1
5. International Journal of Civil, Mechanical and Energy Science (IJCMES) [Vol-5, Issue-2, Mar-Apr, 2019]
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Table 2 shows the gas compositions for the various substrates.
Table.2: Table of gas composition of the flammable gas from experiment
Fig.6: Chart of TS and VS of digested substrates for days 0, 15 and 30
Fig.7: Graph of Ambient Temperature (o
C) against Retention Time (Days)
0
2
4
6
8
10
12
14
16
TS0 TS15 TS30 VS0 VS15 VS30
PERCENTAGE(%)
PERCENTAGES OF TOTAL SOLIDS AND
VOLATILE SOLIDS
SD PP PS SD & PP SD, PP & PS
25
27
29
31
33
35
37
39
41
0 2 4 6 8 1 0 1 2 1 4 1 6 1 8 2 0 2 2 2 4 2 6 2 8 3 0
AMBIENTTEMPERATURE(OC)
TIME (DAYS)
AMBIENT TEMPERATURE VARIATION
Sample Substrates Retention
Time(Day)
Cumulative
Volume of
Biogas(L)
Flammable
Time(Day)
Component of Biogas (% )
CO2
(% )
CO
(% )
CH4
(% )
Other
components
SD (100%) 30 11.5 15 23.5 0.4922 73.0078 3
PP (100%) 30 35.1 5 17.0 0.0373 79.9627 3
PS (100%) 30 39.5 25 17.9 0.0004 79.0996 3
SD (50%)+PP (50%) 30 46.9 26 11.3 0.0011 85.6989 3
SD(40%)+PP(30%)+PS(30%) 30 59.3 2 17.8 0.0039 79.1961 3
6. International Journal of Civil, Mechanical and Energy Science (IJCMES) [Vol-5, Issue-2, Mar-Apr, 2019]
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Fig.8: Graph of Slurry Temperature (o
C) against Retention Time (Days)
Fig.9: Graph of pH of Slurry (o
C) against Retention Time (Days)
Fig.10: Graph of Biochemical Oxygen Demand at various times
25
27
29
31
33
35
37
39
41
43
45
47
0 2 4 6 8 1 0 1 2 1 4 1 6 1 8 2 0 2 2 2 4 2 6 2 8 3 0
SLURRYTEMPERATURE(OC)
TIME (DAYS)
SLURRY TEMPERATURE VARIATION
SD PP PS SD & PP SD, PP & PS
3
4
5
6
7
8
9
0 2 4 6 8 1 0 1 2 1 4 1 6 1 8 2 0 2 2 2 4 2 6 2 8 3 0
PHOFSLURRY
TIME (DAYS)
SAMPLE PH VARIATION
SD PP PS PP & SD SD, PP & PS
0
20
40
60
80
100
120
SD PP PS SD & PP SD, PP & PS
VOLUME OF BOD in mg/l
BOD DAY 0 BOD DAY 15 BOD DAY30
7. International Journal of Civil, Mechanical and Energy Science (IJCMES) [Vol-5, Issue-2, Mar-Apr, 2019]
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Fig.11: Chart showing the TVC of samples for days 0, 15 and 30
Fig.12: Graph of Daily Biogas Yield against Retention Time
Fig.13: Graph of Cumulative biogas yield against Retention Time
0
10000000
20000000
30000000
40000000
50000000
60000000
SD PP PS SD & PP SD, PP & PS
TOTAL VIABLE COUNT incfu/ml
TVC DAY 0 TVC DAY 15 TVC DAY 30
0
2
4
6
8
10
12
14
16
0 2 4 6 8 1 0 1 2 1 4 1 6 1 8 2 0 2 2 2 4 2 6 2 8 3 0
BIOGASYIELD(L)
TIME (DAYS)
DAILY BIOG AS YIELD
SD PP PS SD & PP SD, PP & PS
0
5
10
15
20
25
30
35
40
45
50
55
60
65
0 2 4 6 8 1 0 1 2 1 4 1 6 1 8 2 0 2 2 2 4 2 6 2 8 3 0
CUMULATIVEBIOGASYIELD(L)
TIME (DAYS)
CUMULATIVE BIOG AS YIELD
SD PP PS SD & PP SD, PP & PS
8. International Journal of Civil, Mechanical and Energy Science (IJCMES) [Vol-5, Issue-2, Mar-Apr, 2019]
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EFFECT OF C/N RATIO
C/N ratio is an important indicator for controlling biological
systems. High C/N indicates rapid nitrogen consumption by
methanogens and leads to lower gas production while low
C/N ratio results in ammonia accumulation and an increase
in pH values, which is toxic to methanogenic bacteria
(Zhang et al., 2003). During anaerobic digestion,
microorganisms utilize carbon 25 to 30 times faster than
nitrogen (Yadvika et al., 2004). To meet these requirements,
microbes need 20 to 30:1 ratio of C to N. From the results
of the analysis done on the samples, the table below is
derived
Carbon is required in any anaerobic digestion for building
the cell structure of the methanogenic bacteria. From the
table 1, it can be seen that the C/N ratio of the co-digested
samples was not increased. This can be attributed to the
synergy between the co-digested wastes. From table 1, the
C/N ratio of sample PP and PS; 23.3 and 30.1 were seen to
be within the range of the optimum C/N ratio, this can
account for the early gas production and flammability in the
PP. Late flammability presumes ammonia production due
to low C/N ratio might be predominant at early digestion,
this was seen in the blend of SD & PP. This delay period
was also obtained by Ofoefule and Uzodimma (2009) in the
blend of cassava peels waste with pig dung during
anaerobic digestion process. Low C/N ratio as seen in the
sample SD; 8.5 could be said to be low, leading to ammonia
accumulation which caused an increased lag-time due to
decreased activities of the methanogens.
EFFECT OF TOTAL SOLIDS AND VOLATILE
SOLIDS
Total solid shows the total solid matter constituent of the
entire organic waste both degradable and non-degradable.
Volatile solid is the total amount of the wastes convertible
to gaseous element and providing nutrients to the
microorganisms for their function (biodigestion). Total and
volatile solids content were characterized on the basis of
which it was observed that a waste with high fibre content
such as swine dung possesses lower nitrogen and energy
contents, respectively (Table 1). Higher ash content also
corresponded with higher volatile solids content as can be
seen from the same table.
The total solids and volatile solids content of the various
samples were decreasing over time, this and other
parameters can be said to account for the low level of gas
production. The low value of VS in sample SD led to its
low biogas production since the microbes could not
breakdown the substrates easily.
TEMPERATURE EFFECT
Two distinct temperature ranges for anaerobic digestion
have been noted as the optimum digestion temperature: 35–
55°C (mesophilic range) and 55 °C and above (thermophilic
range). The ambient temperature for all the samples was
always lower than the slurry temperature. The ambient
temperature was affected by the natural weather condition,
this was during the harmattan period (January - February),
when it was usually cold at the early hours of the day and
hot during the day. From figures 7 and 8, the ambient
temperature was between the range of 280C - 39.50C while
the slurry temperature was between the range of 280C -
44.50C for SD, 29.50C - 440C for PP, 280C - 44.50C for PS,
290C - 43.50C for SD & PP, 280C - 450C for SD, PP & PS.
Amongst other determining parameters sample SD, PP &
PS with the highest slurry temperature also had the highest
cumulative biogas yield. Thus, it was carried out under the
most favourable temperature range of 28-39.5oC
(mesophilic condition) which is meant for optimum
anaerobic waste stabilization and of course increased biogas
yield.
EFFECT OF pH VARIATION
The microorganisms that convert waste to biogas are
sensitive to pH. It is generally agreed that at the initial
stages of the overall process of biogas production, acid
forming bacteria produce Volatile Fatty Acids (VFA)
resulting in declining pH and diminishing growth of
methanogenic bacteria and methanogenes (Vicentaet al.,
1984; Cuzinet al., 1992).
That is, a low pH value inactivated microorganisms
responsible for biogas production. The sample PP showed
the highest acidity throughout the retention time with a
range of 4.4 to 6.4. This can be said to account for the low
level of methane production in that it flamed early and
stopped after some days, it could also mean that the number
of acidogens was by far greater than that of the
methanogens. From figure 9, sample PS showed a
continuous decrease in its pH level from 6.6 at charging to
5.5 after some days, this may be due to high VS in the
mixture which was converted more intensely into VFA and
other acidic metabolites by the activities of aerobes and
facultative aerobes that were subsequently metabolized by
methanogenic bacteria to generate biome thane (Dennis &
Burke, 2001; Iyagba et al, 2009).
It was also observed that each of the samples had an
increase in pH on the 28th day, this can be said to be the
reason for the increase in volume of biogas produced.
Sample SD & PP was an improvement for the PP sample as
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the synergy improved the pH of the sample from the range
of 4.4 – 6.4 to the range of 5.0 - 6.7. Sample E also showed
improvement on the pH range from 5.0 – 7.0, considering
the pH of SD, PP and PS which were 6.7, 4.8 and 6.6
respectively.
EFFECT OF TOTAL VIABLE COUNT
The results (from figure 11) showed SD had the highest
level (58.33X105cfu/ml) and PS had the least
(33.33X105cfu/ml) microbial loads at charging, but there
was an appreciable increase of 48.33X106cfu/ml and
15.83X106cfu/ml respectively after 14 days of anaerobic
digestion. However, after 30 days there was a subsequent
decrease (63.33X105cfu/ml and 36.67X105cfu/ml) in the
microbial load. This indicates the fact that SD had more
microbes and PS had the least from onset say due to the
type of food swine feeds on.
100%PS had the least amount of TVC at charging, this can
be said to be responsible for the delay in biogas production
and a lag time of 26 days. The increase in microbial load
was as result of conducive environment and availability of
nutrients needed by microorganisms for growth, it also
accounted for the increased biogas and bio-methane
production after some days. In addition, the subsequent
decrease showedthat the microbial load started depleting
towards the 30th day. In view of the fact that anaerobic
digestion of substrates is generally a function of time,
whereas biogas production is highly dependent on microbial
load, the analysis indicated that gas yield can be predicted
as a function of time and total viable count (TVC).
BIOGAS YIELD AND FLAMMABILITY
From figures 9, 12, 13, table 2, generally, the low volume of
biogas in the biodigestion of SD can be said to be due to the
high concentrations of NH4-N which inhibits the process of
degradation of organic matter, causing a decrease in the
volume of biogas produced (Oparaku et al, 2013). Whereas
the low biogas production of sample PS can be attributed to
the existence of lignin in lignocelluloses which creates a
protective barrier that stops plant cell destruction by fungi
and bacteria for conversion to biogas unless pre-treated
(Angelidaki&Ellegaard, 2003) or due to the accumulation
of VFAs which can result in partial inhibition in the
biodigesters. When the VFAs were consumed, the partial
inhibition was overcome and biogas production started. As
a result of this there was a steady decrease in the pH level,
then a subsequent increase resulting in production of
flammable biogas.
This increase was due to conversion of VFA produced to
methane by methanogens. For sample PP, there was an
upsurge in the activities of the acidogens once more, which
resulted in decrease in pH and reduced flammable biogas.
Flammability is an evidence of about more than 45%
methane content of any anaerobic digestion. However, co-
digestion of the three samples had the same reaction as that
of sample B but it continued flaming from the 2nd day to the
30th day, this indicates that the mixture increased the
percentage methane content consistently which caused it to
continue flaming despite its seeming acidic nature.
V. CONCLUSION
This study has shown that the wastes such as plantain peel,
swine dung and pumpkin stalk which has been termed a
nuisance to the environment can be utilized to produce
biogas which can be used as an alternative to the widely
known and used fossil fuel. The digestate after biogas has
been produced can also be used to as fertilizer to improve
plant growth and enhance soil capability in producing.
From the results,it can be seen that swine dung and plantain
peel are not excellent in producing flammable biogas;
capable of being utilized for any purpose such as cooking.
This showed that in an event when plantain peel had to be
digested alone, it should be pre-treated by the addition of
inoculums or other treatment methods such as neutralizers
to bring the pH to neutrality. Also, swine dung can be
improved by proper grinding of particles for a dry collection
and adequate dilution with water. Pumpkin stalk was seen
to have a very long flammability lag time, although it
showed evidence of producing flammable gas when flaming
commenced. The study showed that the combination of
swine dung and plantain peel improved the production of
biogas tremendously when compared to their individual
capability but it did not necessarily improve the methane
production.
Looking at the mixture that comprised of swine dung,
plantain peel and pumpkin stalk, it can be seen that there
was improvement in both the volume of biogas produced
and the time taken for it to flame. Therefore, it can be
concluded that the co-digestion of the three wastes resulted
in improved biogas production.
This study has shown a new source for wealth creation and
at the same time a means of decontaminating the
environment by waste recycling and transformation. This
wastes that are consumed in large quantities in homes can
be used to produce biogas, this will help themlose the name
attached to themas being nuisance to the environment.
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VI. RECOMMENDATIONS
The following has been recommended as a result of findings
from this work:
The gas produced should be further purified to enhance
its scope of utilization such as in welding and
automobiles.
A method of gas collection which is safe and highly
reliable should be enhanced.
Highly advanced technological equipment should be
constructed for the storing the gas separately from the
digesters.
Equipment that can purify and utilize the biogas that has
been produced can be fabricated; this will encourage
people to use biogas.
Researches should be carried out to discover means of
improving the methane quality produced and also the
quality of the bio-fertilizer left after digestion.
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