The textile industry uses a very great amount of water in their process and then, produces high
quantities of colorful wastewater containing pollutants like suspended solids, heavy metals and other inorganic
and organic compounds. In this study, real textiles wastewaters were processed in an oxidative photo-catalytic
slurry reactor, using commercial ZnO as the catalyst, in order to evaluate its efficiency, the effect of pH, the
effect of catalyst loading and its kinetics. The process was tested in a batch reactor, in bench and semi-pilot
scales, with excellent data reproducibility observed in the scale-up. Moreover, decolorizations of 97.43 %, BOD
and COD reduction were obtained, showing good applicability of the process. According to regional
environmental agencies, the final effluents parameters were checked showing good acceptance for the use of
ZnO, except for the presence of Zn2+ in the effluent as a disadvantage.
Study of Adsorption Isotherm Model and Kinetics on Removal of Zinc Ion from I...IJERA Editor
The removal of Zinc (Zn) metal ion from aqueous solution by using novel bioadsornbent. The impact of beginning metal particle fixation and adsorbent measurements on the adsorption of Zinc (zn) by waste water was researched. The leftover zinc ions was then broke down utilizing Atomic Absorption Spectrophotometer (AAS) (240AA). The adsorption harmony was accomplished when zinc arrangement was 800mg/L. The rate of metal evacuation is of most prominent criticalness for building up a characteristic adsorbent-based watertreatment innovation. The greatest evacuation rate is to be 95.37%. The harmony was accomplished essentially at pH of 7 at 120 minutes and 250 rpm evacuation effectiveness of zinc at steady beginning fixation with 1.25gm measurement infers the capability of gooseberry seeds to adsorb and recoup substantial metals from watery arrangement was effectively exhibited with zinc (zn) test arrangements. The adsorption isotherm studies was done by using Langmuir, Freundlich, temkin, Hill, Jovanovich models and kinetics reaction was studied by pseudo 1st and 2 nd order kinetic reaction. The bioadsorption information fit well with the Temkin isotherm model than the other isotherm model. The kinetics 2nd order reaction was fit to this bioadsorbent than the first order kinetics. Removal of zinc ions from crackers industry waste water was found to be 84%. These outcomes have exhibited the gigantic capability of waste water as an option adsorbent for dangerous metal particles remediation in contaminated wastewater. This paper surveys and investigation the innovative parts of expulsion of zinc from the industrial waste water
Examination of Adsorption Abilities of Natural and Acid Activated Bentonite f...AnuragSingh1049
The effect of the initial concentration of Cr, Co, Cu, Ni, and Pb metal ions from multicomponent solutions on the sorption capacity of natural and acid activated bentonite was examined in this paper. The acid activation was performed by using hydrochloric and sulfuric acid at different concentrations. The results of adsorption research have shown that bentonite can be effectively used as an adsorbent for the removal of metal ions from multicomponent solutions. Acid activation of bentonite changes the structure and content of individual oxides, increases the porosity and the number of available spots for the adsorption process. For this reason, the bentonite removal efficiency increased after acid activation for all heavy metals tested. With increased acid concentration, the degree of bentonite adsorption increased, and sulfuric acid rather than chloric acid showed better results in removal efficiency.
Treatment of Effluent from Granite Cutting Plant by Using Natural Adsorbents ...IJERD Editor
Granite cutting plant is one such industry that releases polluting and turbid effluent. The residue from all these processes is discharged with water as an effluent. The effluent mainly contains many solids that harm the environment. Hence it requires treatment techniques before disposal. Several conventional methods are available for removal of contaminants like coagulation, adsorption, polyelectrolyte methods and biological methods. Most of them are cost prohibitive. The reduction of solids concentration in the effluent before disposal by using the techniques, coagulation followed by adsorption using natural adsorbents, like rice husk carbon and saw dust carbon, in contrast to the usage of activated carbon as it is costly. From a local Granite cutting plant near Anantapur, the effluent is collected and its physico-chemical characteristics are estimated and found to be pH(7.5), TS(4240mg/l), TSS(21560mg/l), TDS(12373mg/l).Effluent obtained is subjected to coagulation by potash alum followed by adsorption using saw dust carbon and rice husk carbon.
An Assessment of Nicotine Levels on Office Surfaces Before and After Use of E...Fontem Ventures
Using the closed or open system e-cigarette products tested in this study did not lead to a measurable increase in nicotine levels on the surfaces analysed. This is consistent with previous reports that e-cigarette users exhale negligible levels of nicotine in to ambient air which may be attributable to the high retention rate of nicotine in the user’s body. Moreover, NNK (a general marker for TSNAs could not be detected on the surfaces analysed at each test phase.
Study of Adsorption Isotherm Model and Kinetics on Removal of Zinc Ion from I...IJERA Editor
The removal of Zinc (Zn) metal ion from aqueous solution by using novel bioadsornbent. The impact of beginning metal particle fixation and adsorbent measurements on the adsorption of Zinc (zn) by waste water was researched. The leftover zinc ions was then broke down utilizing Atomic Absorption Spectrophotometer (AAS) (240AA). The adsorption harmony was accomplished when zinc arrangement was 800mg/L. The rate of metal evacuation is of most prominent criticalness for building up a characteristic adsorbent-based watertreatment innovation. The greatest evacuation rate is to be 95.37%. The harmony was accomplished essentially at pH of 7 at 120 minutes and 250 rpm evacuation effectiveness of zinc at steady beginning fixation with 1.25gm measurement infers the capability of gooseberry seeds to adsorb and recoup substantial metals from watery arrangement was effectively exhibited with zinc (zn) test arrangements. The adsorption isotherm studies was done by using Langmuir, Freundlich, temkin, Hill, Jovanovich models and kinetics reaction was studied by pseudo 1st and 2 nd order kinetic reaction. The bioadsorption information fit well with the Temkin isotherm model than the other isotherm model. The kinetics 2nd order reaction was fit to this bioadsorbent than the first order kinetics. Removal of zinc ions from crackers industry waste water was found to be 84%. These outcomes have exhibited the gigantic capability of waste water as an option adsorbent for dangerous metal particles remediation in contaminated wastewater. This paper surveys and investigation the innovative parts of expulsion of zinc from the industrial waste water
Examination of Adsorption Abilities of Natural and Acid Activated Bentonite f...AnuragSingh1049
The effect of the initial concentration of Cr, Co, Cu, Ni, and Pb metal ions from multicomponent solutions on the sorption capacity of natural and acid activated bentonite was examined in this paper. The acid activation was performed by using hydrochloric and sulfuric acid at different concentrations. The results of adsorption research have shown that bentonite can be effectively used as an adsorbent for the removal of metal ions from multicomponent solutions. Acid activation of bentonite changes the structure and content of individual oxides, increases the porosity and the number of available spots for the adsorption process. For this reason, the bentonite removal efficiency increased after acid activation for all heavy metals tested. With increased acid concentration, the degree of bentonite adsorption increased, and sulfuric acid rather than chloric acid showed better results in removal efficiency.
Treatment of Effluent from Granite Cutting Plant by Using Natural Adsorbents ...IJERD Editor
Granite cutting plant is one such industry that releases polluting and turbid effluent. The residue from all these processes is discharged with water as an effluent. The effluent mainly contains many solids that harm the environment. Hence it requires treatment techniques before disposal. Several conventional methods are available for removal of contaminants like coagulation, adsorption, polyelectrolyte methods and biological methods. Most of them are cost prohibitive. The reduction of solids concentration in the effluent before disposal by using the techniques, coagulation followed by adsorption using natural adsorbents, like rice husk carbon and saw dust carbon, in contrast to the usage of activated carbon as it is costly. From a local Granite cutting plant near Anantapur, the effluent is collected and its physico-chemical characteristics are estimated and found to be pH(7.5), TS(4240mg/l), TSS(21560mg/l), TDS(12373mg/l).Effluent obtained is subjected to coagulation by potash alum followed by adsorption using saw dust carbon and rice husk carbon.
An Assessment of Nicotine Levels on Office Surfaces Before and After Use of E...Fontem Ventures
Using the closed or open system e-cigarette products tested in this study did not lead to a measurable increase in nicotine levels on the surfaces analysed. This is consistent with previous reports that e-cigarette users exhale negligible levels of nicotine in to ambient air which may be attributable to the high retention rate of nicotine in the user’s body. Moreover, NNK (a general marker for TSNAs could not be detected on the surfaces analysed at each test phase.
Decolourisation of Nigrosine WS dye by Solar Photo-fentonAkash Tikhe
My master's dissertation thesis topic- Decolorization of Nigrosine WS dye by Homogeneous Solar Photo-Fenton Method along with Intro, Method, Result, conclusion and suggestions.
Measurement of Radon Exhalation Rates from the Samples of Soil and Rocksijtsrd
Radon and its daughter products are the major sources of radiation exposure and recognized as one of the health hazards for human beings. In the present work, I have reviewed 20 papers in which the soil samples are collected to different places of India and other countries. The Effective radium and radon exhalation rates in the samples of soil and rock have been used passive techniques for alpha particles emission with “Closed Can Technique”, “RRC passive Technique”, “Alpha guard equipment and Gamma tracer”. The soil samples belonging to different places of India and other countries. All the values of radium content in soil samples of study area were found to be quite lower than the permissible value of 370 BqKg 1 recommended by Organization for Economic Cooperation and development OECD1979 . The highest activity Ashima | Sandeep Kansal | Sanjay Aggarwal "Measurement of Radon Exhalation Rates from the Samples of Soil & Rocks" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-4 | Issue-5 , August 2020, URL: https://www.ijtsrd.com/papers/ijtsrd32916.pdf Paper Url :https://www.ijtsrd.com/physics/nuclear-physics/32916/measurement-of-radon-exhalation-rates-from-the-samples-of-soil-and-rocks/ashima
Treatment of Pretreated Landfill Leachate by Membrane Bioreactor ProcessIJAEMSJORNAL
Landfill leachate is a liquid that is mainly produced by the rain which falls on the solid waste. The leachate usually contains high concentrations of ammonium, organic matter, toxic compounds and heavy metals, which makes it unsuitable for discharge in natural bodies without any prior treatment. The formation of leachate threatens the groundwater, soil and environment. Land filling is the one of the least expensive method for disposal of municipal solid waste (MSW). In this study, landfill leachate is treated by coagulation and Membrane Bioreactor (MBR) process by using ultrafiltration (UF). The original sample has BOD/COD ratio as 0.603. Coagulation was used as a pretreatment prior to the biological treatment. . It was done by using alum as an coagulant at an optimum dosage of 160 mg/L. Coagulation has proven effective as a pretreatment. But the effluent quality did not meet the general standards for discharge of environmental pollutants. So the effluent after coagulation process was treated by MBR process. In this study, after MBR treatment all the parameters except BOD have met the relevant Indian Standards for discharge as irrigation water.
Effect of temperature on biodegradation of textile dyeing effluent using pilo...Agriculture Journal IJOEAR
Abstract— This study deals with the effect of temperature on treatment of real textile dyeing effluent using pilot scale two-phase Upflow Anaerobic Sludge Blanket (UASB) reactor with sago effluent as co-substrate under recycle mode. The temperature of the reactor was varied viz. 35, 40, 45 and 50 0C. The feed of the reactor was 30% of methanogenic outlet recycled and 70% of 70/30 (sago/textile dyeing effluent) mixing ratio were given at the bottom of the reactor. The reactor was operated at 24 h of HRT. The performance of the bioreactor was evaluated by monitoring the removal of Chemical Oxygen Demand (COD), removal of color, Volatile Fatty Acid (VFA) and biogas production. The overall COD and color removal were achieved maximum of 98.4% and 99.3% respectively. Based on temperature, the biogas production (0.512 m3/d) was maximum at 450C. From the VFA and alkalinity ratio values obtained indicate that the reactors were operated under steady state. The results shows, that the sago and textile dyeing effluent have wide variation in their characteristics were treated on combination, whereas the recycle ratios maintain the stability of reactor. This new technology supports the effective utilization of sago effluent in destruction of dyeing effluent; the optimum temperature for efficient reactor operation was 450C.
nanotechnology has entered the sphere of water treatment processes. Many different types of nanomaterial’s are being evaluated and also being used in water treatment process.
Desalination is a key market area. Vast majority of worlds water is salt water, and though technology has existed for years that enables the desalination of ocean water, it is often a very energy intensive procedure and therefore expensive
Decolourisation of Nigrosine WS dye by Solar Photo-fentonAkash Tikhe
My master's dissertation thesis topic- Decolorization of Nigrosine WS dye by Homogeneous Solar Photo-Fenton Method along with Intro, Method, Result, conclusion and suggestions.
Measurement of Radon Exhalation Rates from the Samples of Soil and Rocksijtsrd
Radon and its daughter products are the major sources of radiation exposure and recognized as one of the health hazards for human beings. In the present work, I have reviewed 20 papers in which the soil samples are collected to different places of India and other countries. The Effective radium and radon exhalation rates in the samples of soil and rock have been used passive techniques for alpha particles emission with “Closed Can Technique”, “RRC passive Technique”, “Alpha guard equipment and Gamma tracer”. The soil samples belonging to different places of India and other countries. All the values of radium content in soil samples of study area were found to be quite lower than the permissible value of 370 BqKg 1 recommended by Organization for Economic Cooperation and development OECD1979 . The highest activity Ashima | Sandeep Kansal | Sanjay Aggarwal "Measurement of Radon Exhalation Rates from the Samples of Soil & Rocks" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-4 | Issue-5 , August 2020, URL: https://www.ijtsrd.com/papers/ijtsrd32916.pdf Paper Url :https://www.ijtsrd.com/physics/nuclear-physics/32916/measurement-of-radon-exhalation-rates-from-the-samples-of-soil-and-rocks/ashima
Treatment of Pretreated Landfill Leachate by Membrane Bioreactor ProcessIJAEMSJORNAL
Landfill leachate is a liquid that is mainly produced by the rain which falls on the solid waste. The leachate usually contains high concentrations of ammonium, organic matter, toxic compounds and heavy metals, which makes it unsuitable for discharge in natural bodies without any prior treatment. The formation of leachate threatens the groundwater, soil and environment. Land filling is the one of the least expensive method for disposal of municipal solid waste (MSW). In this study, landfill leachate is treated by coagulation and Membrane Bioreactor (MBR) process by using ultrafiltration (UF). The original sample has BOD/COD ratio as 0.603. Coagulation was used as a pretreatment prior to the biological treatment. . It was done by using alum as an coagulant at an optimum dosage of 160 mg/L. Coagulation has proven effective as a pretreatment. But the effluent quality did not meet the general standards for discharge of environmental pollutants. So the effluent after coagulation process was treated by MBR process. In this study, after MBR treatment all the parameters except BOD have met the relevant Indian Standards for discharge as irrigation water.
Effect of temperature on biodegradation of textile dyeing effluent using pilo...Agriculture Journal IJOEAR
Abstract— This study deals with the effect of temperature on treatment of real textile dyeing effluent using pilot scale two-phase Upflow Anaerobic Sludge Blanket (UASB) reactor with sago effluent as co-substrate under recycle mode. The temperature of the reactor was varied viz. 35, 40, 45 and 50 0C. The feed of the reactor was 30% of methanogenic outlet recycled and 70% of 70/30 (sago/textile dyeing effluent) mixing ratio were given at the bottom of the reactor. The reactor was operated at 24 h of HRT. The performance of the bioreactor was evaluated by monitoring the removal of Chemical Oxygen Demand (COD), removal of color, Volatile Fatty Acid (VFA) and biogas production. The overall COD and color removal were achieved maximum of 98.4% and 99.3% respectively. Based on temperature, the biogas production (0.512 m3/d) was maximum at 450C. From the VFA and alkalinity ratio values obtained indicate that the reactors were operated under steady state. The results shows, that the sago and textile dyeing effluent have wide variation in their characteristics were treated on combination, whereas the recycle ratios maintain the stability of reactor. This new technology supports the effective utilization of sago effluent in destruction of dyeing effluent; the optimum temperature for efficient reactor operation was 450C.
nanotechnology has entered the sphere of water treatment processes. Many different types of nanomaterial’s are being evaluated and also being used in water treatment process.
Desalination is a key market area. Vast majority of worlds water is salt water, and though technology has existed for years that enables the desalination of ocean water, it is often a very energy intensive procedure and therefore expensive
Optimization of ultrasonicated membrane anaerobic system (umas) for sewage sl...eSAT Journals
Abstract Ultrasonicated Membrane Anaerobic System UMAS was successfully used for sewage sludge treatment and biogas production. Central Composite Design and Response Surface Methodology were used to determine the optimum conditions in which UMAS produce a maximum content of methane in the biogas produced. The effects of three variables namely pH, chemical oxygen demand (COD) and organic loading rate (OLR) on methane content were evaluated individually and interactively. The optimum conditions obtained were pH 7.74, COD 1061.06 Mg/l and OLR 0.90 kg/m3d. The predicted maximum percentage of methane was 89.72 % and confirmed close to RSM result. Keywords: Optimization, Response Surface Methodology, Sewage Sludge, Ultrasonic, Membrane, Anaerobic Digestion.
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
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
The problem of environmental pollution is more expressed and more present by the development of the industry and the growth of the human population. Pollution of natural and wastewater is most often due to the release of heavy metals into watercourses. The greatest challenge for researchers is choosing the right biomass from a large number of low-cost biomaterials, and availability and price are very important selection factors. Microbial biomass, forestry waste and agroindustrial complexes are most frequently examined, as well as various macromolecules of natural origin. In this paper, barley straw that arises as agricultural waste product in barley production in Bosnia and Herzegovina, was used as a biosorbent. In the experimental part, physical and chemical characterization of barley straw was performed, after which the efficiency of removing Cd(II) and Ni(II) from aqueous solutions, using barley straw, and the influence of process parameters (pH value of aqueous solution, biosorbent size, interaction of metal ions) on the biosorption capacity were tested. It can be concluded that barley straw has good adsoption characteristics for the use as a low-cost natural sorbent for the removal of heavy metals from water.
Anaerobic Treatment of Textile Wastewater using EGSBIJSRD
In this study expanded granular sludge bed (EGSB) reactor has been used to investigate the removal efficiency of chemical oxygen demand (COD), and color of textile wastewater. Synthetic Textile wastewater was treated in an EGSB reactor seeded with non granular anaerobic sludge from UASB reactor treating sugar mill wastewater of Badagandi sugar mill at Badagandi village, Bagalkot district, Karnataka, India and active septic tank. The initial volatile suspended solid concentration was 20.40 g/L. The study was carried out at ambient temperature 29ºC to 37ºC in the laboratory scale reactors of 8.4 L effective volume. Reactor was fed with macro and micro nutrients. Successful reactor startup with granulation was achieved within 13 days of operation using Chitosan as polymer. During startup the hydraulic retention times (HRT) was kept constant for 12 hrs. A maximum COD removal efficiency of 89.95% was achieved at organic loading rate (OLR) of about 8 KgCOD/m3/d. And the maximum bio gas production was 20.4 l/d. During operation period synthetic textile wastewater was fed step by step with increasing concentration of 25%, 50% and 75% of influent COD (5000 mg/L) respectively. Loading was increased by reducing HRT to 6 hrs, 3 hrs, 1.5 hrs and 1 hr respectively. Results indicated that anaerobic treatment of textile wastewater was possible with the supplementation of an external carbon source in the form of glucose (600mg/L). The corresponding maximum COD and color removals were 78.4% and 69% respectively for HRT of 1.5 hrs and OLR of 80 Kg COD/m3/d at ambient temperature.
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
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
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.
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.
Cars are a very important part of this modern world because they give luxury and comfort. Even
though they are comfortable, some problems always keep arising on the safety side. After a lot of research they
rectified certain problems using air bags, auto parking, turbo charger, pedal shift…, etc.
And now we are going to discuss about one such problem that arises on the safety side. An unsuspected
accident occurs when people smash their fingers in between the car doors. Due to this kind of accident around
120,000 people are injured every year. But this was not taken as a very major safety concern for the customer.
To avoid this kind accident due to car doors, we are introducing “SAFETY DOOR LOCK SYSTEM”
with the help of “HYDRAULIC PISTON AND IR SENSORS”.
The major working process of the “SAFETY DOOR LOCK SYSTEM”is, when a person places his/her
hand or fingers in the gap between the door and the outer panel, at the time when the closing action of the door
takes place, the Sensors start to transmit the Infra Red Rays to the Receivers at the
other end, and so even if someone closes the door without anybody‟s knowledge the hydraulic piston will
automatically come out and stop the door from closing and prevent the person from the unsuspected accident
and minor injuries by the car door and ensure maximum safety to the customer.
Extrusion can be defined as the process of subjecting a material to compression so that it is forced to
flow through an opening of a die and takes the shape of the hole. Multi-hole extrusion is the process of
extruding the products through a die having more than one hole. Multi-hole extrusion increases the production
rate and reduces the cost of production. In this study the ram force has calculated experimentally for single hole
and multi-hole extrusion. The comparison of ram forces between the single hole and multi-hole extrusion
provides the inverse relation between the numbers of holes in a die and ram force. The experimental lengths of
the extruded products through the various holes of multi-hole die are different. It indicates that the flow pattern
is dependent on the material behavior. The micro-hardness test has done for the extruded products of lead
through multi-hole die. It is observed that the hardness of the extruded lead products from the central hole is
found to be more than that of the products extruded from other holes. The study suggests that multi-hole
extrusion can be used for obtaining the extruded products of lead with varying hardness. The micro-structure
study has done for the lead material before and after extrusion. It is observed that the size of grains of lead
material after extrusion is smaller than the original lead.
Analysis of Agile and Multi-Agent Based Process Scheduling Modelirjes
As an answer of long growing frustration of waterfall Software development life cycle concepts,
agile software development concept was evolved in 90’s. The most popular agile methodologies is the Extreme
Programming (XP). Most software companies nowadays aim to produce efficient, flexible and valuable
Software in short time period with minimal costs, and within unstable, changing environments. This complex
problem can be modeled as a multi-agent based system, where agents negotiate resources. Agents can be used to
represent projects and resources. Crucial for the multi-agent based system in project scheduling model, is the
availability of an effective algorithm for prioritizing and scheduling of task. To evaluate the models, simulations
were carried out with real life and several generated data sets. The developed model (Multi-agent based System)
provides an optimized and flexible agile process scheduling and reduces overheads in the software process as it
responds quickly to changing requirements without excessive work in project scheduling.
Effects of Cutting Tool Parameters on Surface Roughnessirjes
This paper presents of the influence on surface roughness of Co28Cr6Mo medical alloy machined
on a CNC lathe based on cutting parameters (rotational speed, feed rate, depth of cut and nose radius).The
influences of cutting parameters have been presented in graphical form for understanding. To achieve the
minimum surface roughness, the optimum values obtained for rpm, feed rate, depth of cut and nose radius were
respectively, 318 rpm, 0,1 mm/rev, 0,7 mm and 0,8 mm. Maximum surface roughness has been revealed the
values obtained for rpm, feed rate, depth of cut and nose radius were respectively, 318 rpm, 0,25 mm/rev, 0,9
mm and 0,4 mm.
Possible limits of accuracy in measurement of fundamental physical constantsirjes
The measurement uncertainties of Fundamental Physical Constants should take into account all
possible and most influencing factors. One from them is the finiteness of the model that causes the existence of
a-priori error. The proposed formula for calculation of this error provides a comparison of its value with the
actual experimental measurement error that cannot be done an arbitrarily small. According to the suggested
approach, the error of the researched Fundamental Physical Constant, measured in conventional field studies,
will always be higher than the error caused by the finite number of dimensional recorded variables of physicalmathematical
models. Examples of practical application of the considered concept for measurement of fine
structure constant, speed of light and Newtonian constant of gravitation are discussed.
Performance Comparison of Energy Detection Based Spectrum Sensing for Cogniti...irjes
With the rapid deployment of new wireless devices and applications, the last decade has witnessed a growing
demand for wireless radio spectrum. However, the policy of fixed spectrum assignment produces a bottleneck for more
efficient spectrum utilization, such that a great portion of the licensed spectrum is severely under-utilized. So the concept of
cognitive radio was introduced to address this issue.The inefficient usage of the limited spectrum necessitates the
development of dynamic spectrum access techniques, where users who have no spectrum licenses, also known as secondary
users, are allowed to use the temporarily unused licensed spectrum. For this purpose we have to know the presence or
absence of primary users for spectrum usage. So spectrums sensing is one of the major requirements of cognitive radio.Many
spectrum sensing techniques have been developed to sense the presence or absence of a licensed user. This paper evaluates
the performance of the energy detection based spectrum sensing technique in noisy and fading environments.The
performance of the energy detection technique will be evaluated by use of Receiver Operating Characteristics (ROC) curves
over additive white Gaussian noise (AWGN) and fading channels.
Comparative Study of Pre-Engineered and Conventional Steel Frames for Differe...irjes
In this paper, the conventional steel frames having triangular Pratt truss as a roofing system of 60 m
length, span 30m and varying bay spacing 4m, 5m and 6m respectively having eaves level for all the portals is at
10m and the EOT crane is supported at the height of 8m from ground level and pre-engineered steel frames of
same dimensions are analyzed and designed for wind zones (wind zone 2, wind zone 3, wind zone 4 and wind
zone 5) by using STAAD Pro V8i. The study deals with the comparative study of both conventional and preengineered
with respect to the amount of structural steel required, reduction in dead load of the structure.
Flip bifurcation and chaos control in discrete-time Prey-predator model irjes
The dynamics of discrete-time prey-predator model are investigated. The result indicates that the
model undergo a flip bifurcation which found by using center manifold theorem and bifurcation theory.
Numerical simulation not only illustrate our results, but also exhibit the complex dynamic behavior, such as the
periodic doubling in period-2, -4 -8, quasi- periodic orbits and chaotic set. Finally, the feedback control method
is used to stabilize chaotic orbits at an unstable interior point.
Energy Awareness and the Role of “Critical Mass” In Smart Citiesirjes
A Smart City could be depicted as a place, logical and physical, in which a crowd of heterogeneous
entities is related in time and space through different types of interactions. Any type of entity, whether it is a
device or a person, clustered in communities, becomes a source of context-based data.
Energy awareness is able to drive the process of bringing our society to limit energy waste and to optimize
usage of available resources, causing a strong environmental and social impact. Then, following social network
analysis methodologies related to the dynamics of complex systems, it is possible to find out, emergent and
sometimes hidden new habits of electricity usage. Through an initial Critical Mass, involving a multitude of
consumers, each related to more contexts, we evaluate the triggering and spreading of a collective attitude. To
this aim, in this paper, we propose a novel analytical model defining a new concept of critical mass, which
includes centrality measures both in a single layer and in a multilayer social network.
A Firefly Algorithm for Optimizing Spur Gear Parameters Under Non-Lubricated ...irjes
Firefly algorithm is one of the emerging evolutionary approaches for complex and non-linear
optimization problems. It is inspired by natural firefly‟s behavior such as movement of fireflies based on
brightness and by overcoming the constraints such as light absorption, obstacles, distance, etc. In this research,
firefly‟s movement had been simulated computationally to identify the best parameters for spur gear pair by
considering the design and manufacturing constraints. The proposed algorithm was tested with the traditional
design parameters and found the results are at par in less computational time by satisfying the constraints.
The Effect of Orientation of Vortex Generators on Aerodynamic Drag Reduction ...irjes
One of the main reasons for the aerodynamic drag in automotive vehicles is the flow separation
near the vehicle’s rear end. To delay this flow separation, vortex generators are used in recent vehicles. The
vortex generators are commonly used in aircrafts to prevent flow separation. Even though vortex generators
themselves create drag, but they also reduce drag by delaying flow separation at downstream. The overall effect
of vortex generators is more beneficial and proved by experimentation. The effect depends on the shape,size and
orientation of vortex generators. Hence optimized shape with proper orientation is essential for getting better
results.This paper presents the effect of vortex generators at different orientation to the flow field and the
mechanism by which these effects takes place.
An Assessment of The Relationship Between The Availability of Financial Resou...irjes
The availability of financial resources is an important element in impacting the success of a planning
process for an effective physical planning. The extent to which however, they are articulated in the process
remained elusive both in scholarly and public discourse. The objective of this study wastherefore, to examine
the extent to which financial resources affect physical planning. In doing so, the study examinedwhether
financial resources were adequate or not to facilitate planning processes in Paidha. According to the study
findings,budget prioritization and ceilings are still a challenge in Paidha Town Council. This is partly due
limited level of knowledge of physical planning among the officials of Paidha Town Council. As a result, there
were no dedicated budget line for routine inspection of physical development plan compliance and enforcement
tools in Paidha. In conclusion, in addressing uncoordinated patterns of physical development that characterize
Uganda‟s urban centres, a critical starting point ought to be the analysis of physical planning process. The
research of this kind is not only significant to other emerging urban centres facing poor a road network,
mushrooming informal settlements and poor social services including poor pattern of residential and commercial
developments but also to all institutions that are involved in planning these towns. Knowing the extent of need
for financial influences in planning may assist local authorities to take the processes of planning seriously which
will help enhance the sustainable development of emerging urban centres including Paidha.
The Choice of Antenatal Care and Delivery Place in Surabaya (Based on Prefere...irjes
- Person's desire to do a pregnancy examination is determined by the service place that suits the tastes
and facilities owned by it. Until now, the utilization of antenatal care by pregnant women is still low (Mardiana,
2014). The purpose of the study is to analyze factors affecting the utilization of antenatal care and delivery place
in Surabaya city based on the preferences and choice theory.
Type of survey research is cross sectional approach, the population is mothers who have children aged 1-
12 months in Surabaya. The large sample of 250 mothers who have children aged 1-12 months in 2013 is taken
by simple random sampling technique. Variables of the research are the preference elements and steps, choice
elements and steps, utilization of antenatal care and delivery place. Data were collected through questionnaires
and secondary data were then analyzed with descriptive statistics in the form of a frequency distribution, shown
by the schematic diagram.
The result showed that the preference elements and steps showed almost half (42.9%) desire to give birth
in a health care because of information got from someone else, while the choice element and step shows the
bulk (57.1%) of the criteria of delivery place chosen is a safe, comfortable and cheap delivery place, the labor
place which is the main choice most (57.1%) is cheap, comfortable, close.
Conclusion of the research based on the preferences and choice theory can be found three (3) new
theories, they are preferences become choice, preferences do not become choice, choice is preceded by
preferences
Observability Concepts EVERY Developer Should Know -- DeveloperWeek Europe.pdfPaige Cruz
Monitoring and observability aren’t traditionally found in software curriculums and many of us cobble this knowledge together from whatever vendor or ecosystem we were first introduced to and whatever is a part of your current company’s observability stack.
While the dev and ops silo continues to crumble….many organizations still relegate monitoring & observability as the purview of ops, infra and SRE teams. This is a mistake - achieving a highly observable system requires collaboration up and down the stack.
I, a former op, would like to extend an invitation to all application developers to join the observability party will share these foundational concepts to build on:
Removing Uninteresting Bytes in Software FuzzingAftab Hussain
Imagine a world where software fuzzing, the process of mutating bytes in test seeds to uncover hidden and erroneous program behaviors, becomes faster and more effective. A lot depends on the initial seeds, which can significantly dictate the trajectory of a fuzzing campaign, particularly in terms of how long it takes to uncover interesting behaviour in your code. We introduce DIAR, a technique designed to speedup fuzzing campaigns by pinpointing and eliminating those uninteresting bytes in the seeds. Picture this: instead of wasting valuable resources on meaningless mutations in large, bloated seeds, DIAR removes the unnecessary bytes, streamlining the entire process.
In this work, we equipped AFL, a popular fuzzer, with DIAR and examined two critical Linux libraries -- Libxml's xmllint, a tool for parsing xml documents, and Binutil's readelf, an essential debugging and security analysis command-line tool used to display detailed information about ELF (Executable and Linkable Format). Our preliminary results show that AFL+DIAR does not only discover new paths more quickly but also achieves higher coverage overall. This work thus showcases how starting with lean and optimized seeds can lead to faster, more comprehensive fuzzing campaigns -- and DIAR helps you find such seeds.
- These are slides of the talk given at IEEE International Conference on Software Testing Verification and Validation Workshop, ICSTW 2022.
GraphSummit Singapore | The Future of Agility: Supercharging Digital Transfor...Neo4j
Leonard Jayamohan, Partner & Generative AI Lead, Deloitte
This keynote will reveal how Deloitte leverages Neo4j’s graph power for groundbreaking digital twin solutions, achieving a staggering 100x performance boost. Discover the essential role knowledge graphs play in successful generative AI implementations. Plus, get an exclusive look at an innovative Neo4j + Generative AI solution Deloitte is developing in-house.
GraphRAG is All You need? LLM & Knowledge GraphGuy Korland
Guy Korland, CEO and Co-founder of FalkorDB, will review two articles on the integration of language models with knowledge graphs.
1. Unifying Large Language Models and Knowledge Graphs: A Roadmap.
https://arxiv.org/abs/2306.08302
2. Microsoft Research's GraphRAG paper and a review paper on various uses of knowledge graphs:
https://www.microsoft.com/en-us/research/blog/graphrag-unlocking-llm-discovery-on-narrative-private-data/
Essentials of Automations: The Art of Triggers and Actions in FMESafe Software
In this second installment of our Essentials of Automations webinar series, we’ll explore the landscape of triggers and actions, guiding you through the nuances of authoring and adapting workspaces for seamless automations. Gain an understanding of the full spectrum of triggers and actions available in FME, empowering you to enhance your workspaces for efficient automation.
We’ll kick things off by showcasing the most commonly used event-based triggers, introducing you to various automation workflows like manual triggers, schedules, directory watchers, and more. Plus, see how these elements play out in real scenarios.
Whether you’re tweaking your current setup or building from the ground up, this session will arm you with the tools and insights needed to transform your FME usage into a powerhouse of productivity. Join us to discover effective strategies that simplify complex processes, enhancing your productivity and transforming your data management practices with FME. Let’s turn complexity into clarity and make your workspaces work wonders!
GridMate - End to end testing is a critical piece to ensure quality and avoid...ThomasParaiso2
End to end testing is a critical piece to ensure quality and avoid regressions. In this session, we share our journey building an E2E testing pipeline for GridMate components (LWC and Aura) using Cypress, JSForce, FakerJS…
Pushing the limits of ePRTC: 100ns holdover for 100 daysAdtran
At WSTS 2024, Alon Stern explored the topic of parametric holdover and explained how recent research findings can be implemented in real-world PNT networks to achieve 100 nanoseconds of accuracy for up to 100 days.
PHP Frameworks: I want to break free (IPC Berlin 2024)Ralf Eggert
In this presentation, we examine the challenges and limitations of relying too heavily on PHP frameworks in web development. We discuss the history of PHP and its frameworks to understand how this dependence has evolved. The focus will be on providing concrete tips and strategies to reduce reliance on these frameworks, based on real-world examples and practical considerations. The goal is to equip developers with the skills and knowledge to create more flexible and future-proof web applications. We'll explore the importance of maintaining autonomy in a rapidly changing tech landscape and how to make informed decisions in PHP development.
This talk is aimed at encouraging a more independent approach to using PHP frameworks, moving towards a more flexible and future-proof approach to PHP development.
Elevating Tactical DDD Patterns Through Object CalisthenicsDorra BARTAGUIZ
After immersing yourself in the blue book and its red counterpart, attending DDD-focused conferences, and applying tactical patterns, you're left with a crucial question: How do I ensure my design is effective? Tactical patterns within Domain-Driven Design (DDD) serve as guiding principles for creating clear and manageable domain models. However, achieving success with these patterns requires additional guidance. Interestingly, we've observed that a set of constraints initially designed for training purposes remarkably aligns with effective pattern implementation, offering a more ‘mechanical’ approach. Let's explore together how Object Calisthenics can elevate the design of your tactical DDD patterns, offering concrete help for those venturing into DDD for the first time!
GDG Cloud Southlake #33: Boule & Rebala: Effective AppSec in SDLC using Deplo...James Anderson
Effective Application Security in Software Delivery lifecycle using Deployment Firewall and DBOM
The modern software delivery process (or the CI/CD process) includes many tools, distributed teams, open-source code, and cloud platforms. Constant focus on speed to release software to market, along with the traditional slow and manual security checks has caused gaps in continuous security as an important piece in the software supply chain. Today organizations feel more susceptible to external and internal cyber threats due to the vast attack surface in their applications supply chain and the lack of end-to-end governance and risk management.
The software team must secure its software delivery process to avoid vulnerability and security breaches. This needs to be achieved with existing tool chains and without extensive rework of the delivery processes. This talk will present strategies and techniques for providing visibility into the true risk of the existing vulnerabilities, preventing the introduction of security issues in the software, resolving vulnerabilities in production environments quickly, and capturing the deployment bill of materials (DBOM).
Speakers:
Bob Boule
Robert Boule is a technology enthusiast with PASSION for technology and making things work along with a knack for helping others understand how things work. He comes with around 20 years of solution engineering experience in application security, software continuous delivery, and SaaS platforms. He is known for his dynamic presentations in CI/CD and application security integrated in software delivery lifecycle.
Gopinath Rebala
Gopinath Rebala is the CTO of OpsMx, where he has overall responsibility for the machine learning and data processing architectures for Secure Software Delivery. Gopi also has a strong connection with our customers, leading design and architecture for strategic implementations. Gopi is a frequent speaker and well-known leader in continuous delivery and integrating security into software delivery.
UiPath Test Automation using UiPath Test Suite series, part 5DianaGray10
Welcome to UiPath Test Automation using UiPath Test Suite series part 5. In this session, we will cover CI/CD with devops.
Topics covered:
CI/CD with in UiPath
End-to-end overview of CI/CD pipeline with Azure devops
Speaker:
Lyndsey Byblow, Test Suite Sales Engineer @ UiPath, Inc.
Threats to mobile devices are more prevalent and increasing in scope and complexity. Users of mobile devices desire to take full advantage of the features
available on those devices, but many of the features provide convenience and capability but sacrifice security. This best practices guide outlines steps the users can take to better protect personal devices and information.
Securing your Kubernetes cluster_ a step-by-step guide to success !KatiaHIMEUR1
Today, after several years of existence, an extremely active community and an ultra-dynamic ecosystem, Kubernetes has established itself as the de facto standard in container orchestration. Thanks to a wide range of managed services, it has never been so easy to set up a ready-to-use Kubernetes cluster.
However, this ease of use means that the subject of security in Kubernetes is often left for later, or even neglected. This exposes companies to significant risks.
In this talk, I'll show you step-by-step how to secure your Kubernetes cluster for greater peace of mind and reliability.
Securing your Kubernetes cluster_ a step-by-step guide to success !
Evaluation of the photo-catalytic oxidation process with commercial ZnO for real textiles wastewaters treatment.
1. International Refereed Journal of Engineering and Science (IRJES)
ISSN (Online) 2319-183X, (Print) 2319-1821
Volume 3, Issue 12 (December 2014), PP.01-07
www.irjes.com 1 | Page
Evaluation of the photo-catalytic oxidation process with
commercial ZnO for real textiles wastewaters treatment.
Célia R. G. Tavares1
, Valquíria A. S. Ribeiro2
, and André L. S. Volpe3
1, 2, 3
Department of Chemical Engineering, State University of Maringá (UEM), D-90, 87020-900,
Maringá, PR, Brazil,
Abstract:- The textile industry uses a very great amount of water in their process and then, produces high
quantities of colorful wastewater containing pollutants like suspended solids, heavy metals and other inorganic
and organic compounds. In this study, real textiles wastewaters were processed in an oxidative photo-catalytic
slurry reactor, using commercial ZnO as the catalyst, in order to evaluate its efficiency, the effect of pH, the
effect of catalyst loading and its kinetics. The process was tested in a batch reactor, in bench and semi-pilot
scales, with excellent data reproducibility observed in the scale-up. Moreover, decolorizations of 97.43 %, BOD
and COD reduction were obtained, showing good applicability of the process. According to regional
environmental agencies, the final effluents parameters were checked showing good acceptance for the use of
ZnO, except for the presence of Zn2+
in the effluent as a disadvantage.
I. INTRODUCTION
The nature of pollutants and their concentrations in industrial wastewater depends on their source.
Industrial wastewater typically leaves the units at higher temperatures than communal and agricultural
wastewater. Because of the high concentrations of toxic materials in industrial wastewater, it is necessary to
apply specific processes for their separation, transformation, and further decomposition. A variety of biological,
physical, and chemical processes and their combinations are available for these purposes, but each technique
has its inherent limitations in applicability, effectiveness, and cost [1].
The wastewaters generated by the textile industry are among the most polluting because of the
presence of dyes, fabrics fiber, and various other substances considered dangerous for the environment, besides
the large amount of water that is discarded in the effluent. Because of that, many studies have been realized in
order to find even better treatments for these wastewaters, such as the photo-catalytic oxidation.
Catalytic processes for wastewater treatment offer several advantages. They can be performed under
milder conditions (temperatures and pressures). Another great advantage of catalytic methods is the possibility
to treat only a single pollutant, or a group of similar pollutants, out of a complex mixture of pollutants (as in
selective catalytic reduction). This opportunity is of special interest when a mixture of pollutants and useful
compounds should be processed. By proper choice of the catalyst, it is possible not only to control the degree of
conversion of pollutants but also to select different reaction routes, in order to select the optimal reaction
intermediates and products and avoid the formation of secondary pollutants [1].
The photo-catalytic oxidation has been widely studied because it is able to mineralize organic
compounds without producing other compounds that harm the environment, and does not produce significant
amounts of silt. The process consists of irradiating the effluent in the presence of a semiconductor, which
generates radicals that accelerate the destruction of organic compounds.
When illuminated with an appropriate light source, these semiconductors generate electron/hole pairs,
with electrons promoted to the conduction band and leaving positive holes in the valence band. The generated
electron/hole pairs initiate a complex series of chemical reactions involving vestigial organic compounds
adsorbed at the surface of the semiconductor that might result in the complete degradation of the adsorbates [4].
The zinc oxide (ZnO) has been widely studied as a semiconductor for the degradation of several environmental
pollutants due to its high photo-sensitive, chemical stability, non-toxicity and low cost [4, 6, 7, 18].
II. MATERIALS AND METHODS
a. The Reactors.
In the laboratory scale, the slurry reactor was built using a becker of 2000 mL positioned onto a
magnetic stirrer, in order to keep the solution homogenous with the effluent in constant agitation. A
thermostatical bath kept the temperature in 25 o
C. Using a support, 4 germicidal lamps of 15 W for the UV
irradiation were fixed onto the becker, and the system was isolated from the external radiation. Commercial
ZnO was used as the catalyst, with specific superficial area - BET of 0.00636 m2
Kg-1
. The effluent pH was
adjusted using sulfuric acid and sodium hydroxide solutions with undefined concentrations. The catalyst was
added to 450 mL of the effluent, hence was submitted to agitation for 10 minutes in the dark in order to
2. Evaluation of the photo-catalytic oxidation process with commercial ZnO for real textiles...
www.irjes.com 2 | Page
complete the homogenization of the solution, after these 10 minutes 50 mL of the solution were collected as the
initial sample and then, the 400 mL remaining in the reactor were submitted to the UV irradiation during 4
hours.
The slurry reactor in semi-pilot scale consisted of a fiberglass tank with a capacity of 0.320 m3
and the
following dimensions: base diameter of 0.77 m, top diameter of 0.96 m and 0.50 m high. An engine that
produces 800 rpm and 2 shovels with width of 0.06 m each, and the total diameter of the agitator of 0.17 m did
the agitation. The stirring blades were positioned at 0.10 m high from the base. A structure of baffles was
assembled, with six baffles with width of 0.050 m and 0.30 m high, to avoid the formation of vortex. The 44
germicidal lamps of 15 W used in the tests were fixed in a stainless-steel plate of 1.00 m of diameter which was
fitted onto the tank. A rubber was fixed at the edge of the reactor to minimize the impact of the stainless-steel
plate and to prevent leakage of ultraviolet radiation to the exterior of the tank.
The slurry reactor in semi-pilot scale was built in an industrial laundry of the town, for the treatment of
effluent generated. The effluent was fed into the reactor by gravity and the volume transferred was measured by
a hydrometer. The effluent pH was adjusted to 4.0 using concentrated sulfuric acid. Commercial zinc oxide was
used as the catalyst, with specific surface area - BET of 0.00636 m2
Kg-1
. In all experiments, 0.100 m3
of
effluent were treated, using 3.0 Kg m-3
of zinc oxide. During the tests the reaction time was 4 hours, initial and
final samples of the solution were collected to evaluate the decolorization, reduction of COD and “apparent”
color of the effluent.
b. Analytical Methods.
The COD was determinated using the micro-method [5], and the BOD was determined from the
standard method [21].
The pH was measured using a Digimed’s pHmeter model DM20, according to the methodology
described in the manual of the equipment.
The samples were centrifuged in a rate of 3000 rpm for 20 minutes to completely remove catalyst
particles, and then were submitted to spectrophotometric analysis.
The apparent color, that is the color of the dissolved materials plus the suspended matter, and turbidity
were determined in a HACH spectrophotometer, model DR/2010, at a wavelength of 455 nm and 860 nm,
respectively, according to the methods described in the manual of the equipment.
The spectrophotometric scans were performed on a spectrophotometer HACH-LANGE, model
DR/5000. The decolorization of the effluent was determined at the wavelength of maximum absorbance (λmax)
of each effluent. These decolorizations have been calculated as:
100
)(
(%)
i
fi
Abs
AbsAbs
tionDecoloriza
where Absi is the absorbance of the solution before the treatment and Absf is the absorbance of the solution after
the treatment.
The metals: Lead (Pb), Copper (Cu), Chrome (Cr), Iron (Fe), Nickel (Ni) and Zinc (Zn) were measured
by atomic absorption spectroscopy using the method called the Fast Sequential Atomic Absorption
Spectrometer, model AA240FS according to the methodology described in the operations manual of the
equipment. The calibrations curves of the metals occurred through the use of specific standards for each metal
at different concentrations. Only the determination of the Pb concentration to construct the curve occurred with
standards of Pb in ppb.
c. Development.
Throughout the study, six effluents were collected from an industrial laundry located in Maringá,
Paraná State, in Brazil; at different periods of the year. These effluents were characterized for the following
parameters: pH, "apparent" color, wavelength of maximum absorbance, turbidity, COD, BOD and heavy
metals.
Initially, experiments were performed in bench scale in order to determine the initial pH of the solution
in which it was obtained the better efficiency of the process of photo-catalytic oxidation. After that, the
concentration of zinc oxide that provided better results of decolorization of the effluent was also analyzed. With
the optimum conditions determined, experiments were realized to determine the kinetics of the process, in
which samples of 10 mL were collect at intervals of 30 min during the 4 hours of experiment using a pipette.
The 10 mL of samples were chosen to not quite interfere in the total volume, what could change the conditions
of the process, and were enough for doing the analysis.
3. Evaluation of the photo-catalytic oxidation process with commercial ZnO for real textiles...
www.irjes.com 3 | Page
In addition to the bench scale tests, other tests were conducted in the semi-pilot scale photo-reactor built in the
laundry where industrial effluents were collected to analyze whether the optimum conditions of the experiment
obtained at bench scale would lead to the same good results in the semi-pilot scale.
III. RESULTS AND DISCUSSIONS
3.1. Effluents Characterization.
Information from the laundry told that the chemicals most used were: reactive dyes, chlorine, sodium
hydroxide, potassium permanganate, sodium metabisulfite, enzymes, optical brighteners, humectants,
sequestrants, dispersants, reducers, softening, hydrogen peroxide, detergents among others with more specific
uses but in smaller quantities.
Real wastewater contains many other organic compounds than dyes, compared to synthetic wastewater,
and the produced hydroxyl radicals from the photocatalysys reacts with any kind of organic compounds, what
may decrease the efficiency of the degradation of the dye[19]. The diversity of the process in the laundry and
the use of reactive dyes, which have in their chromophore group the structure N = N on the aromatic structure,
leads to the use of a wide range of chemicals, giving to the wastewater strong color and high pollution potential,
with possible carcinogenic and mutagenic activity, making these effluents dangerous to humans and aquatic
ecosystems. The regional environmental agencies recommend values for COD below 0.125 Kg m-3
, BOD below
0.050 Kg m-3
and for color below 0.075 Kg PtCo m-3
.
The effluents were characterized concerning to various parameters and the results are shown in the Table 1
below:
Table 1: Characterization of the brute effluents.
PARAMETER Effluent 1 Effluent 2 Effluent 3 Effluent 4 Effluent 5 Effluent 6
pH 6.4 7.3 7.2 6.6 7.5 6.7
Color (Kg PtCo m-3
) 0.218 0.517 0.335 0.572 0.746 0.1056
Turbidity (FAU) 87 112 75 121 93 146
Wave length (nm) 664 481 608 655 660 477
COD (Kg O2 m-3
) 0.2464 0.2402 0.2090 0.2361 0.2380 0.2237
BOD (Kg O2 m-3
) * * * 0.03785 0.03006 0.03372
DQO/DBO * * * 6,23 7,91 6,63
Lead (ppm) 0.22 0.16 0.31 0.12 0.17 0.18
Copper (ppm) 0.04 0.06 0.05 0.05 0.05 0.15
Chrome (ppm) 0.04 0.05 0.06 0.05 0.05 0.05
Iron (ppm) 0.32 0.17 0.11 0.04 0.16 0.22
Nickel (ppm) 0.03 0.02 0.03 0.03 0.03 0.04
Zinc (ppm) 0.20 0.01 nd Nd nd nd
* - Not performed.
nd - not detected.
The results presented in Table 1 showed that the parameters of color and COD were higher than the
recommended by the environmental agencies and the effluent required proper treatment and also showed that
the characteristics of the wastewater changes according to the different periods of the year because there was a
variation in the activities of the industrial laundry, using more or fewer dyes, what can difficult the treatment of
the effluent to ensure that they always be within the limits for disposal in the environment. The effluents also
presented high values of turbidity what may difficult the pass of UV rays through the suspension in the reactor,
harming the process. The rate COD/BOD showed the difficult of treating the wastewater with biological process
since the BOD of the effluents were below 0.050 Kg m-3
. According to the metals (Pb, Cu, Cr, Fe, Ni e Zn), the
effluent was within the estabilished limits for disposal.
3.2. Effect of initial pH.
The effluents 1, 2 and 3 were used in bench scale experiments to find the pH and the concentration of
ZnO in suspension that provide the best efficiency. Therefore, experiments were performed changing the pH of
the effluent in a range of 4-10 and the percentage of decolorization was analyzed. The other parameters were
adopted as the ones optimized by Veiber [22] as follows: the concentration of zinc oxide was at 2 Kg m-3
, the
volume of reaction was 400 mL, four 15 W germicidal lamps were used and the reaction occurred in 4 hours.
The results of the effluent’s decolorization as a function of the pH of the solution are shown in Figure 4.
4. Evaluation of the photo-catalytic oxidation process with commercial ZnO for real textiles...
www.irjes.com 4 | Page
Figure 4: Efficiency of the photo-oxidative process as a function of pH of the solution.
As observed, the pH can be one of the most important parameters in the efficiency of the
photodegradation process [23, 12], since it directly influences the surface charge of the particle and also the
formation of oxidizing and reducing sites in the catalyst, thus determining the efficiency and stability of the
suspension. The pH is related to the ionization of the surface of the reactants and products in the solution, since
the degradation of the dye occurs by the contribution of three reaction mechanisms: the hydroxyl radical attack,
direct oxidation by the positive gap and the direct reduction by the electron in the conduction band (depending
on the nature of the substrate). ZnO is an amphoteric oxide and its point of zero charge is in pH = 9 [12]. The
adsorption of the dye molecules in the ZnO surface happens widely in acid pH, when the surface of the catalyst
is positively charged, and this may be the reason of higher decolorizations in the acid pH. In alkaline pH, the
ZnO surface becomes negatively charged because of the adsorbed OH-
, with less available sites for the dye
adsorption. The high concentration of OH-
in the ZnO surface also difficult the adsorption of the molecular
oxygen, decreasing the efficiency of the photodegradation [10, 13].
The Figure 4 shows that the highest decolorization occurred in the acid pH = 4, in which were obtained
decolorizations of respectively 85 %, 62 % and 69 % for the effluents 1, 2 and 3. The catalytic activity
decreased with the increase of the pH, presenting none decolorization for the effluent 3 using the pH of 9 and
10. The difference of the efficiency for the three effluents happened due to the different quantities of chemicals
released in the wastewaters by the process of the laundry, changing the conditions of the reaction.
The results are in agreement with those obtained by [23], who studied the photocatalytic degradation of
the Acid Violet dye, having a composite of zinc oxide with activated carbon (ZnO: AC) as the catalyst. These
researchers have found that the ZnO:AC photo-activation showed a better efficiency in acid pH (2.0),
attributing the increase in efficiency in acidic solution to the perhydroxyl radical, which can form the hydrogen
peroxide, which then gives rise to hydroxyl radical, promoting the degradation. Another similar result was
found on the photocatalytic process using ZnO to the decolorization of "Yellow Cassafix CA-3R" in which the
authors obtained the greatest degradation at pH 4.0 [24].
However, these results contradict those obtained by other researchers who used ZnO as the catalyst,
and have found the best degradation of dyes in an alkaline solution [2, 6-9]. Since those results were obtained
with synthetic effluents, such results might reflect the presence of other compounds in the real wastewater that
may be changing the normal optimum conditions.
The pH was not controlled during the experiment and was only measured in the final sample, showing
that the final pH of the suspension was between 6.5 and 8.0 for the three effluents. This was attributed to the
amphoteric character of ZnO acting as an acid in a basic solution and acting as a base in a acid solution.
The experiments also showed that the effluents with higher “apparent” color were the ones that had
less decolorization. This result is in agreement to [2, 3, 6-9, 17, 23]. These authors argue that the efficiency of
decolorization is inversely affected by the concentration of the dye, thus the greater the color of the effluent, the
lower will be the degradation.
3.3. Effect of catalyst loading.
The next optimized parameter was the catalyst loading. Thus, experiments were made using different
concentrations of ZnO for the effluents 1, 2 and 3. The concentrations 2.0, 3.0 and 3.5 Kg m-3
were tested
keeping the other parameters fixed like as the previous experiments and the pH was adjusted to 4.0 in the
beginning of each test. The results of decolorization are shown in Figure 5:
5. Evaluation of the photo-catalytic oxidation process with commercial ZnO for real textiles...
www.irjes.com 5 | Page
Figure 5: Efficiency of the process as a function of the catalyst loading.
Note: The test with 3.5 Kg.m-3
was not performed for the effluent 2.
The concentration of 3.0 Kg m-3
of the catalyst provided the higher decolorization for the three
effluents according to Figure 5: 97.43% for the effluent 1, 86.53% for the effluent 2 and 88.09% for the effluent
3. It happened because increasing the concentration of ZnO the surface area where the reaction can be catalyzed
increases, but very high concentrations can interfere in the pass of the ultra-violet radiation in the solution or
result in the deactivation of activated molecules by collision with ground state molecules decreasing the
efficiency of the process [2, 6, 8, 9, 11, 14-17, 23]. Therefore, the concentration of 3.0 Kg m-3
of ZnO was
adopted in the following experiments.
For the tests performed with the concentration of the catalyst of 3.0 Kg m-3
, zinc concentrations of
20.8, 31.1 and 28.6 ppm were detected in the final samples for the effluents 1, 2 and 3 respectively showing that
part of the zinc in the catalyst was dissolved during the photodegradation process, provided that analysis
showed there was no zinc dissolved in the beginning of the experiment. Other author also have obtained similar
results with low pH in his study of photocatalytic degradation with ZnO [8, 12]. This makes the effluent unfit
disposal, since the CONAMA, which is the National Council of the Environment in Brazil, regulates it in the
Resolution 357/2005, the concentration of zinc in the effluent for disposal has to be lower than 0.005 Kg m-3
.
3.4. Kinetics study.
The Langmuir-Hinshelwood model, ln(Co/C)=k.t, where Co is the initial concentration and C is the
concentration at any time (t), was tested in the process and the fit is presented in Figure 6. The process followed
the pseudo-first order kinetics [6, 10, 11, 14, 16], with correlation constant for the fit of R2
=0.9793 and the rate
constant calculated to be k=0.0073 min-1
.
Figure 6: Kinetic fit for the photo catalytic process.
3.5. Experiments in semi-pilot scale.
Photo degradation experiments with the effluents 4 and 5 were performed in the photo-reactor in semi-
pilot scale using the optimal conditions obtained previously in order to analyze its reproducibility. The results
are shown in Table 2:
6. Evaluation of the photo-catalytic oxidation process with commercial ZnO for real textiles...
www.irjes.com 6 | Page
Table 2: Evaluation of the photo-degradation in semi-pilot scale.
PARAMETER Effluent 4 Effluent 5
Inicial Color (Kg PtCo m-3
) 0.572 0.746
Final Color (Kg PtCo m-3
) 0.036 0.063
Inicial Absorbance 0.229 0.256
Final Absorbance 0.020 0.013
Decolouration (%) 91.3 95.0
Inicial COD (Kg O2 m-3
) 0.2361 0.2402
Final COD (Kg O2 m-3
) 0.1304 0.1217
Reduction of the COD (%) 44.8 49.33
Zinco Inicial Zinc (ppm) nd nd
Final Zinc (ppm) 32.1 34.7
nd - not detected.
The results presented in Table 2 shows that the parameters optimized in bench scale were enough to
obtain the reproducibility of the process in semi-pilot scale, providing the color removal and reduction of COD.
Again it was observed that the effluent that had higher concentration of color showed the lowest decolorization,
and color values below the limit established by CONAMA Resolution 357/2005 for disposal in the environment
were obtained for both effluents.
In regards to COD, the process efficiency for the effluent 5 was slightly higher than that obtained for
the effluent 4. For the effluent 4, the final concentration of COD was slightly above the limit set by the
environmental agencies.
Again, it was found the occurrence of solubilization of the catalyst, leaving the wastewater out of the
acceptable standards for disposal, confirming the need of further treatment for zinc removal, in order to fit the
environmental regulations.
IV. CONCLUSION
With the characterization of the industrial effluents obtained from the laundry the need of an effective
treatment for color removal and COD and BOD reduction before its disposal in the environment can be
confirmed, since these parameters were above the limits allowed by regional environmental agencies.
The tests to determine the pH, which provides the activation of the catalysts sites, indicated pH 4.0 as
the ideal for better efficiency of the effluents decolorization, but solubilization of zinc oxide was observed in the
acid solution, which can be a limiting factor to the use of photocatalysis under these conditions.
The tests to determine the best concentration of ZnO indicated that 3.0 Kg m-3
was the concentration
that achieved the best decolorization of the effluent, above this concentration the degradation of the dye
decreased, losing efficiency significantly. The results showed that the advanced oxidation process using ZnO as
the catalyst was efficient in color removal and COD reduction of real textile wastewaters.
It was found that the metals presence in the effluents before the treatment were within the limits
established by CONAMA for disposal in the enviroment and remained so after the treatment except for the zinc,
which solubilized during the photocatalytic process increasing its concentration in the treated effluent. Thus, the
ZnO use as the catalyst under these conditions requires a specific treatment for its removal before the disposal
in the environment.
Nomenclature.
ZnO: Zinc oxide
BOD: Biological Oxigen Demand (ML-3
)
COD: Chemical Oxigen Demand (ML-3
)
λmax: Maximum Absorbance Wavelenght (L)
Absi: Solution’s absorbance before the treatment
Absf: Solution’s absorbance after the treatment
ACKNOWLEDGMENT
The authors would like to thanks the University of Maringá, especially to the Chemical Engineering
Department where most of the tests were performed, the CAPES and CNPq for the financial support and the
laundry that released the effluents to the tests.
7. Evaluation of the photo-catalytic oxidation process with commercial ZnO for real textiles...
www.irjes.com 7 | Page
REFERENCES
[1]. Y. I. Matatov-Meytal, M. Sheintuch, Catalytic Abatement of Water Pollutants. Ind. Eng. Chem. Res., 37 (2)
(1998) 309-326.
[2]. A. Akyol, H. C. Yatmaz, M. Bayramoglu, Photocatalytic decolorization of Remazol Red RR in aqueous
ZnO suspensions. Applied Catalysis B: Environmental 54 (2004) 19-24.
[3]. A. Akyol, M. Bayramoglu, The degradation of an azo dye in a batch slurry photocatalytic reactor. Chemical
Engineering and Processing. 47 (2008) 2150-2156.
[4]. J. Marto, P. São Marcos; T. Trindade; J.A. Labrincha, Photocatalytic decolouration of Orange II by ZnO
active layers screen-printed on ceramic tiles. Journal of Hazardous Materials 163 (2009) 36-42.
[5]. Standard methods for the examination of water and wastewater, 19th ed., published by American Public
Health Association, 1995.
[6]. S. K. Kansal, A. H. Ali, S. Kapoor, Photocatalytic decolorization of biebrich scarlet dye in aqueous phase
using different nanophotocatalysts. Desalination 259 (2010) 147–155.
[7]. H. Wang, C. Xie, W. Zhang, S. Cai, Z. Yang, Y. Gui, Comparison of dye degradation efficiency using ZnO
powders with various size scales. Journal of Hazardous Materials 141 (2007) 645–652.
[8]. M.A. Behnajady, N. Modirshahla, R. Hamzavi, Kinetic study on photocatalytic degradation of C.I. Acid
Yellow 23 by ZnO photocatalyst. Journal of Hazardous Materials B133 (2006) 226–232.
[9]. S. Sakthivel, B. Neppolian, M.V. Shankar, B. Arabindoo, M. Palanichamy, V. Murugesan, Solar
photocatalytic degradation of azo dye: comparison of photocatalytic efficiency of ZnO and TiO2. Solar
Energy Materials & Solar Cells 77 (2003) 65–82.
[10]. Wei Shouqiang, Shao Zhongcai, Lu Xudong, Liu Ying, Cao Linlin, He Yan, Photocatalytic degradation of
methyl orange over ITO/CdS/ZnO interface composite films. Journal of Environmental Sciences 21(2009)
991–996.
[11]. A. Nageswara Rao, B. Sivasankar, V. Sadasivam, Kinetic study on the photocatalytic degradation of
salicylic acid using ZnO catalyst. Journal of Hazardous Materials 166 (2009) 1357–1361.
[12]. R. Comparelli, E. Fanizza, M.L. Curri, P. D. Cozzoli ,G. Mascolo, A. Agostiano, UV-induced photocatalytic
degradation of azo dyes by organic-capped ZnO nanocrystals immobilized onto substrates. Applied
Catalysis B: Environmental 60 (2005) 1–11.
[13]. R.Y. Hong, J.H. Li, L.L. Chen, D.Q. Liu, H.Z. Li, Y. Zheng, J. Ding, Synthesis, surface modification and
photocatalytic property of ZnO nanoparticles. Powder Technology 189 (2009) 426–432.
[14]. Li-Yun Yang, Shu-Ying Dong, Jian-Hui Sun, Jing-Lan Feng, Qiu-Hua Wu, Sheng-Peng Sun, Microwave-
assisted preparation, characterization and photocatalytic properties of a dumbbell-shaped ZnO photocatalyst.
Journal of Hazardous Materials 179 (2010) 438–443.
[15]. Yinhua Jiang, Yueming Sun, Hui Liu, Fuhong Zhu, Hengbo Yin, Solar photocatalytic decolorization of C.I.
Basic Blue 41 in an aqueous suspension of TiO2-ZnO. Dyes and Pigments 78 (2008) 77-83.
[16]. N. Daneshvar, D. Salari, A.R. Khataee, Photocatalytic degradation of azo dye acid red 14 in water on ZnO
as an alternative catalyst to TiO2. Journal of Photochemistry and Photobiology A: Chemistry 162 (2004)
317–322.
[17]. U. I. Gaya, A. H. Abdullah, M. Z. Hussein, Z. Zainal, Photocatalytic removal of 2,4,6-trichlorophenol from
water exploiting commercial ZnO powder. Desalination 263 (2010) 176–182.
[18]. B. Neppolian, H.C. Choi, S. Sakthivel,Banumathi Arabindoo, V. MurugesanSolar/UV-induced
photocatalytic degradation of three commercial textile dyes. Journal of Hazardous Materials B89 (2002)
303–317.
[19]. E. R. Bandala, M. A. Peláez, A. J. García-López, M. J. Salgado, G. Moeller, Photocatalytic decolourisation
of synthetic and real textile wastewater containing benzidine-based azo dyes Chemical Engineering and
Processing 47 (2008) 169–176
[20]. D. C. Lenhard, 2010, Tratamento de efluentes têxteis em reatores foto-oxidativos. Doctor thesis, State
University of Maringá, Brazil.
[21]. S.A. Silva, R. Oliveira, 2010, Manual de Análises físico-químicas de águas de abastecimento e residuárias.
State University of Ponta Grossa, Brazil.
[22]. R. E. Veiber, 2009, Tratamento de efluentes têxteis por foto-oxidação catalítica. Master thesis. State
University of Maringá, Brazil.
[23]. K. Byrappa, A. K. Subramani, S. Ananda, K. M. Lokanatharai, M. H. Sunitha, B. Basavalingu, K. Soga,
Impregnation of ZnO onto activated carbon under hydrothermal conditions and its photocatalytic properties.
J MATER SCI 41 (2006) 1355–1362.
[24]. E. M. Silva, G. G. C. Lima, C. A. P. Lima, F. F. Vieira, 2007, Tratamento de corante têxtil “Amarelo
Cassafix CA-3R” por processo fotocatalítico utilizando ZnO. 24º Congresso Brasileiro de Engenharia
Sanitária e Ambiental, Brazil.
[25]. V. A. S. Ribeiro, 2010, FOTODEGRADAÇÃO DE EFLUENTES TÊXTEIS CATALISADA POR ZnO
Master thesis. State University Fo Maringá, Brazil.