Your SlideShare is downloading. ×
International Journal of Advances in Engineering & Technology, Mar. 2013.©IJAET                                           ...
International Journal of Advances in Engineering & Technology, Mar. 2013.©IJAET                                           ...
International Journal of Advances in Engineering & Technology, Mar. 2013.©IJAET                                           ...
International Journal of Advances in Engineering & Technology, Mar. 2013.©IJAET                                           ...
International Journal of Advances in Engineering & Technology, Mar. 2013.©IJAET                                           ...
International Journal of Advances in Engineering & Technology, Mar. 2013.©IJAET                                           ...
International Journal of Advances in Engineering & Technology, Mar. 2013.©IJAET                                           ...
International Journal of Advances in Engineering & Technology, Mar. 2013.©IJAET                                           ...
International Journal of Advances in Engineering & Technology, Mar. 2013.©IJAET                                           ...
International Journal of Advances in Engineering & Technology, Mar. 2013.©IJAET                                           ...
International Journal of Advances in Engineering & Technology, Mar. 2013.©IJAET                                           ...
Upcoming SlideShare
Loading in...5
×

CHARACTERIZATION OF INCINERATED MEDICAL WASTE RESIDUES USING BATCH LEACHING

223

Published on

The hospital wastes produced during the course of health-care activities pose a threat to public health and environment than any other type of wastes. In the present paper physiochemical properties of the incinerated solid waste sample such as sampling, batch test operation, sequential extraction and chemical speciation have been studied. The results show that the concentration of heavy metals decreases with increase in L/S ratio. Batch test analyse shows the static view of leachate produced by the ash and sequential extraction shows the potential mobility of heavy metals. Chemical speciation and distribution of heavy metals varied greatly this trend was due to the higher ion exchange capacity of the extractants and formation of anionic metal species, leading to more metal species leaching out of each chemical fraction.

Published in: Design
0 Comments
0 Likes
Statistics
Notes
  • Be the first to comment

  • Be the first to like this

No Downloads
Views
Total Views
223
On Slideshare
0
From Embeds
0
Number of Embeds
0
Actions
Shares
0
Downloads
13
Comments
0
Likes
0
Embeds 0
No embeds

No notes for slide

Transcript of "CHARACTERIZATION OF INCINERATED MEDICAL WASTE RESIDUES USING BATCH LEACHING"

  1. 1. International Journal of Advances in Engineering & Technology, Mar. 2013.©IJAET ISSN: 2231-1963 CHARACTERIZATION OF INCINERATED MEDICAL WASTE RESIDUES USING BATCH LEACHING N. Nagendra Gandhi1, P. Arunraj2, and R. Thirumalai Kumar3 1 Professor and Head, 2 Department of Chemical Engineering, A.C. Tech., Anna University, Chennai, India3 Department of Oil and Gas Engineering, All Nations University College, Koforidua-Ghana, West AfricaABSTRACTThe hospital wastes produced during the course of health-care activities pose a threat to public health andenvironment than any other type of wastes. In the present paper physiochemical properties of the incinerated solidwaste sample such as sampling, batch test operation, sequential extraction and chemical speciation have beenstudied. The results show that the concentration of heavy metals decreases with increase in L/S ratio. Batch testanalyse shows the static view of leachate produced by the ash and sequential extraction shows the potentialmobility of heavy metals. Chemical speciation and distribution of heavy metals varied greatly this trend was dueto the higher ion exchange capacity of the extractants and formation of anionic metal species, leading to moremetal species leaching out of each chemical fraction.KEYWORDS: Medical Waste, Batch Leaching, Waste Residue, Incineration I. INTRODUCTIONHospital is one of the complex institutions, which is frequented by people from every walk of life in thesociety. Waste is always a sensitive topic for public, health-care waste is especially so. The medicalwastes are increasing in its amount and type over a period of time due to increased inhabitants andadvances in science and technology. In pursuing their aims of reducing health problems and eliminatingpotential risks to people’s health, health care services inevitably create waste that may itself behazardous to health. Technically solid waste is any waste which is not discharged into the air and hencethe term can be applied to liquids. Solid waste comprises the largest percentage of hospital generatedwaste and includes such waste types as general office trash, food service waste and even the fastestgrowing waste type, recyclable waste. The impact of rare earth elements from medical waste incineratedash residues. Crust normalized patterns indicated medical wastes were enriched with Ce and La. DTPAand EDTA extraction tests revealed rare earth elements were generally low in bioavailability.Sequential extraction studies revealed that the leaching of heavy metals depends upon composition ofcalcium evaluated the leaching characteristics of heavy metals in municipal solid waste incinerator flyash.The potential release of Pb, Zn, Cr, and Cu in municipal solid waste incinerator (MSWI) fly ash wasinvestigated by batch leaching experiments using sodium acetate solution as the extractant. Theconcentrations of heavy metals decreased against the increase of liquid-to-solid (L/S) ratio with theexception of Zn. The slag obtained from incinerated hospital waste. The sources of health care wastecan be classified as major or minor according to the quantities produced. The major sources are listedbelow: university hospital, general hospital, district hospital. Other health care’s establishments likeemergency medical care services, health care centre’s dispensaries, obstetric and maternity clinics,outpatient clinics, first-aid and sick bays, long term health care establishments and hospices, transfusion 214 Vol. 6, Issue 1, pp. 214-224
  2. 2. International Journal of Advances in Engineering & Technology, Mar. 2013.©IJAET ISSN: 2231-1963centers and military medical services. Thirdly related laboratories and research centre, medical andbiomedical laboratories biotechnology laboratories and institutions, medical research centre. Finallyblood banks, blood collection services and nursing home the elderly.II. MATERIALS AND METHODS2.1. SamplingThe residual ash samples are obtained from the Common Bio-Medical Waste Treatment Facility(CBMWTF) located near Padappai (Chennakuppam)-Chennai. This facility has a treatment capacity of15,000 beds. At present, 157 healthcare units have registered with this facility to supply wastes of only2400-3100 beds per day. This unit is located 60 km away from the city, 3 km away from the habitats.Incineration and autoclaving are the main processes in these facilities. The residual ashes were firstidentified and an adequate sampling period (two months) was presumed for collection of samples dueto temporal variability in the ash. The point of generation was determined, as for bottom ash thecollection was at grate siftings and combustion chamber. The increments are obtained by falling streamand stationary stream which are likely to produce representative samples. Primarily about 12 incrementsof 5kg increments were collected from the stream. They are sub sampled to obtain a 2 kg lot from whichabout 0.5 kg was obtained for analysis. The spacing of the increments was varied, as the sampling wascollected at different discharge. The sampling devices used are shovel and bucket.2.2. Graduation AnalysisThe sieve analysis test is used to determine the size distribution of the aggregates and is a suitablemethod for bottom ash. The grain size distribution gives the percentage by weight of different sizes ofthe particles, which are used to assess other physical properties such as shear strength, bearing capacity,permeability. The grain sizes were determined using varying sieves. The following mesh sizes 10, 30,60, 100, 200 are used to obtain the residues at various fractions.2.3. Loss of Ignition (LOI)Loss of ignition (LOI) has been used to provide an indication of the degree of burnout achieved duringcombustion or the combustion efficiency. LOI is determined by the weight loss of the residual ashsamples, previously dried for 24 hours at 105ºC after exposure to 550ºC in a muffle furnace forsufficient time to achieve a constant weight. Typically the results are expressed as a percentage of thedried sample weight. LOI was calculated using the equation (1). 𝑊 𝐷𝐴 −𝑊 𝑀𝐴 LOI = 𝑊 𝐷𝐴 × 100…………………. (1)where; WDA = weight of ash dried at 105ºC in grams, WMA = weight of ash muffled at 550ºC in grams.2.4. Experimental Methodology for Batch TestTwo different types of batch tests were developed to characterize the leaching potential associated withthe incinerated residues: contact time tests and sequential extraction tests. The contact time test providesan estimate of the time necessary to mobilize minerals from solid wastes. This test also provides insightinto the sequence of dissolution, allowing for the identification of readily soluble species, thus providinga static view of the interaction between the leachant and the waste material. The sequential extractiontest provides a dynamic view of the material’s behavior as it encounters fresh leachant at regular timeintervals. This test allows for simulation of the sequential changes in leaching mechanisms that occuras fresh water interacts with the waste material.2.4.1. Batch Test OptimizationPreliminary batch tests were conducted to optimize the liquid to solid (L/S) mass ratios of distilled waterto ash and the duration of the contact intervals. The first study focused on determining the contact timeintervals necessary for diffusion to occur, while providing adequate volume to conduct leachatecharacterization tests. The leachates from the preliminary batch tests were characterized and the data 215 Vol. 6, Issue 1, pp. 214-224
  3. 3. International Journal of Advances in Engineering & Technology, Mar. 2013.©IJAET ISSN: 2231-1963from these initial tests was used to develop a final protocol for the testing of the incinerated residuesamples.2.4.2. Preliminary Contact Time TestsThe preliminary batch tests, designed to determine the contact time requirements of the ash and theleachant were conducted using an L/S ratio of 10. This ratio L/S = 10, the waste can be considered100% solid and any residual water in the material can be disregarded in the calculation of leachant wasterelationships. The ash samples were placed in individual bottles and distilled water was added until anL/S ratio of 10 was reached based on an average density of 1 g/mL for distilled water. The contact timesranged from 24 to 48 hours. At the end of the assigned time interval, the leachate was removed andtested for pH.2.4.3. Preliminary Sequential Extraction TestsThe second set of this test is used to assess difference in leaching based on the L/S ratio. As before, theremoved leachate was tested for a limited number of parameters. However, upon removing the leachateat the end of 48 hours, an equal amount of distilled water was used to replenish the leachant, thusmaintaining a constant L/S ratio in the bottle but increasing the total L/S ratio over time. The L/S of 2,4 and 6 did not provide sufficient leachate for analysis. Based on this information, the actual batch testswere based on an L/S value of either 8 or 10. The results from the preliminary batch tests were used toset basic parameters for the contact time and sequential extraction batch tests. The establishment ofequilibrium at approximately 48 hours influenced the time intervals used in both types of batch tests.The L/S =10 was determined to be the best option since sufficient leachate was produced for analysisand the solid required no pre-treatment.2.4.4. Contact Time TestsThe contact time batch test was designed to yield a static view of the interaction between the wastematerial and the leachant. The initial set-up for all batch tests was identical; 125 mL HDPE bottles werepre-cleaned by soaking in an acid bath of 1% nitric acid for 24 hours. The bottles were then rinsed fivetimes with distilled water and allowed to air dry for two to three days. Once completely dried, the bottleswere placed on an analytical balance, tarred, and approximately 10grams of ash were added to eachbottle. The exact mass was recorded and sufficient distilled water was added to achieve an L/S = 10.The volume added was usually slightly more than 10 ml, which completely fills the bottle, eliminatingheadspace. At the end of each time interval, the three bottles were removed from the incubator and theleachate was removed by filtration. The leachate was divided into three volumes, one for immediatetesting and the other two were preserved for chemical characterization.2.5. Sequential Extraction (SE)2.5.1. Exchangeable fraction40mL of 0.11molL acetic acid was added to 1.0 g of dry residues in a 50-mL polypropylene tube. Themixture was shaken for 16 hr then the extract was separated from the solid phase by centrifugation at3800 rpm for 20 min. The supernatant liquid was decanted into a100-mL beaker and then covered witha watch-glass. The residue was washed by adding 20mL of double-distilled water, shaking for 15 min,and then centrifuging. The second supernatant liquid was discarded without any loss of residue.2.5.2 Iron and Manganese oxides fractionMetals bound to iron and manganese oxides were extracted by adding 40ml of 0.1molL hydroxylammonium chloride (adjusted to pH2 with 2molL nitric acid) on to the residue from the first step. Aftershaking the mixture for 16 h it was centrifuged for 15 min, and then decanted into a beaker. Using 20mL of distilled water, the residue was washed, centrifuged, and the supernatant was preserved.2.5.3 Organic Matter Fraction10mL of 8.8molL hydrogen peroxide as carefully added in small aliquots to the residue in the centrifugetube. The tube ingredients were digested at room temperature for 1h with occasional manual shaking.The procedure was continued for 1h and the volume reduced to a few millilitres by further heating in a 216 Vol. 6, Issue 1, pp. 214-224
  4. 4. International Journal of Advances in Engineering & Technology, Mar. 2013.©IJAET ISSN: 2231-1963water bath. A second aliquot of 10mL of hydrogen peroxide was added to the residue and the digestionprocedure was repeated. The solution was heated to near dryness, and 50 mL of1.0molL ammoniumacetate solution (adjusted to pH 2 with nitric acid) was added to the moist residue. The samples solutionwas shaken and centrifuged, and the extract was separated as described above.2.5.4 Residual FractionThe analysis of the residue was performed using aqua regia for metals insoluble in the previous steps.For this purpose, 6 mL of distilled water and then aqua regia solution in a sequence of 15 and10mLwere added to the remaining residue. After adding each aqua regia solution, the residue was evaporatedto near dryness on a water bath. The extract was filtered through filter paper by adding 1 mol litreHNO3 solution in small amounts on the last residue in the centrifuge tube. The tube walls were carefullywashed with the same acids solution and then collected in a beaker.2.6 Chemical SpeciationA total of 1M sodium acetate was used as the leachant in these batch leaching experiments. Five L/Sratios, 5, 10, 15, 20, and 25, were chosen to determine the releasing behaviour of heavy metals from thebottom ash. Other batch leaching experiments were conducted with a series of solutions with a pH rangefrom 2 to 12 when the L/S ratio was fixed at 10. For each leaching experiment, the first 10 g of bottomash was placed in a bottle, and then the leaching solvent was added in the appropriate L/S ratio.Subsequently, the container was closed and then shaken in a horizontal shaker for 8 h at roomtemperature. The samples were allowed to settle for approximately 16 h. After pH values weremeasured, the solutions were filtered, and then analyzed. The raw sample was acid digested using(HNO3 + HCl) and the heavy metals concentration were determined. Three replicates were developedto identify the heavy metals concentration. The heavy metals were measured using Atomic Absorptionspectrometer (AAS).III. RESULTS AND DISCUSSIONS3.1 Gradation AnalysisThe presence of glass, wood and unburned solid residues are separated to obtain uniform sized particles.These individual fractions are further utilized for physical and chemical characterization. Thesegradation analysis are helpful to segregate the particles (<1mm) by which the chemical speciation ofmetals are studied further. Figure 1. Particle size distribution of bottom ash residues 217 Vol. 6, Issue 1, pp. 214-224
  5. 5. International Journal of Advances in Engineering & Technology, Mar. 2013.©IJAET ISSN: 2231-19633.2 Loss of Ignition (LOI) of Bottom Ash Figure 2. Bottom Ash LOI as function of particle sizeFrom the figure 2 it can be seen, there is a maxima, at a larger particle size (mesh size #60 for sample1 and mesh #30 for sample 2) which is uncombusted material. The other tends to be at very smallparticle sizes and reflects the fact that very fine materials in bottom ashes can be organic materials.3.3 Batch Leaching Tests3.3.1 pH and alkalinityLeachates from all ash samples had relatively high levels of pH regardless of source or leachateextraction method. The pH values for the leachate produced using the CT test ranged from pH = 10.3to 12.0 are presented in Figure 3. Alkalinity is a measure of the buffering capacity of a solution, and thealkalinity results differ depending on the type of batch test used to produce the leachate and the sourceof the ash. 14 12 10 8 pH 6 Series1 4 2 0 0 20 40 60 L/S ratio Figure 3. Contact time batch test pH results for Bottom ash3.3.2 Solubility and release as function of L/S Ratio 218 Vol. 6, Issue 1, pp. 214-224
  6. 6. International Journal of Advances in Engineering & Technology, Mar. 2013.©IJAET ISSN: 2231-1963The concentrations of heavy metals decreased with an increase in the L/S ratio with the exception ofZn at L/S ratio of 20 in sample 2. When the L/S ratio was higher than 20, the amounts of heavy metalsthat leached out changed slightly. Because bottom ash contains large amounts of alkaline compounds,it has strong acid buffering capability so that the heavy metals in the samples could not be easily releasedinto the leachate due to the low equilibrium concentrations. In the case of low L/S ratios, theconcentrations of Pb and Zn were relatively high. But in high L/S ratios, the total amounts of Pb andZn declined because of the dilution and neutralization processes that would result in the decrease of pHvalue and the re-precipitation of heavy metals that dissolved previously. 25 Concentration of metals (mg/L) 20 15 Pb 10 Ni Zn 5 0 0 5 10 15 20 25 30 L/S ratio Figure 4. Concentration of metals with respect to L/S ratio (sample1) 18 Concentration of metals (mg/L) 16 14 12 10 Pb 8 Ni 6 4 Zn 2 0 0 5 10 15 20 25 30 L/S ratio Figure 5. Concentration of metals with respect to L/S ratio (sample 2)3.3.3 Solubility and release as function of pHThe change of pH values would lead to different leaching patterns. The concentrations of heavy metalsdeclined along with the increase of initial pH of leaching solvent. When the pH value was higher than6, the concentrations of Pb remained at a low level. The relationship between initial pH of the leaching 219 Vol. 6, Issue 1, pp. 214-224
  7. 7. International Journal of Advances in Engineering & Technology, Mar. 2013.©IJAET ISSN: 2231-1963solvent and the leachate pH revealed that values greater than pH 6 shows gradual increase. Thiscorresponds the fact that higher L/S ratio does not influence the amount of heavy metals dissolved. Theconcentration of lead declines with increase in pH. When the pH value is higher than 6, theconcentrations of heavy metals remained at low level. 90 Concentration of metals (mg/L) 80 70 60 50 Pb 40 30 Ni 20 Zn 10 0 0 5 10 15 pH Figure 6. Concentration of metals with respect to pH (sample1) 60 Concentration of metals (mg/L) 50 40 30 Pb 20 Ni Zn 10 0 0 5 10 15 pH Figure 7. Concentration of metals with respect to pH (sample2)3.3.4 Sequential ExtractionChemical fraction distribution of each metal differed vastly as shown in Figure 6 and 7. About Pb waspresent in F1, and the contents of F2 and F3 were less. Zn exhibited a similar distribution in that thecontents of F2. Ni concentrations were high in exchangeable fraction F1, whereas in F2 and F3represented very less. 220 Vol. 6, Issue 1, pp. 214-224
  8. 8. International Journal of Advances in Engineering & Technology, Mar. 2013.©IJAET ISSN: 2231-1963 18 Conc. of metal species (ppm) 16 14 12 10 Pb 8 6 Ni 4 Zn 2 0 0 2 4 6 Conc. of Ammonium acetate (M) Figure 8. Concentration of metals bound to exchangeable fraction (F1) 3 Con of metal species (ppm) 2.5 2 1.5 Pb 1 Ni 0.5 Zn 0 0 2 4 6 Conc of acetic acid (M) Figure 9. Contcentration of metals bound to carbonate fraction (F2) 3.5 3 Con of metal species (ppm) 2.5 2 Pb 1.5 Ni 1 Zn 0.5 0 0 1 2 3 4 5 6 Conc. of NH2OH-HCl (M) Figure 10. Contcentration of metals bound to Fe=Mn oxides (F3)From the results it has been observed that Pb, Zn, are mainly present in the F1, Ni present almost in allthe fraction F1, F2, F3, with equal amount. Hence the leachability could be well controlled in naturalenvironment. But if there are sufficient amounts of reducing agents, heavy metals bound to Fe-Mnoxides (F3) would be gradually leached out, especially Pb and Zn. It is suggested that reducingconditions could accelerate the leaching process of bottom ash and a serious risk would be brought to 221 Vol. 6, Issue 1, pp. 214-224
  9. 9. International Journal of Advances in Engineering & Technology, Mar. 2013.©IJAET ISSN: 2231-1963the landfill sites. Heavy metals bound to organic compounds (F2) could be transported to theenvironment slowly by reacting with complexing agents or oxidants, but they are not easily leached outunder normal natural conditions. Heavy metals in residual condition are usually incorporated into thecrystals, and thus the metals could not be dissolved even in destructive acidity conditions.IV. CONCLUSIONS1) The physical characterization of the incinerated medical wastes reveals that the properties of the solidresidues (bottom ash) depends upon composition of feed, type of incinerator used, and operatingconditions and so on.2) The batch test developed for this work fell into two categories: contact time and sequential extraction.The contact time test provided a static view of the leachate produced by the ash, since the leachantremained in contact with the same material long enough to establish equilibrium. The readily solublematerials leached out of the ash and become part of the leachate.3) The sequential extraction test provided a dynamic view of the leaching properties of ash as freshleachant encountered the material.4) The concentration of heavy metals in the leachate was rather low and decreased against the rise ofL/S ratio with the exception of Zn. In the case of low L/S ratios, the concentrations of Pb and Zn wererelatively high. A change in pH values led to different leaching patterns. The concentrations of heavymetals declined along with the rise of initial pH of leaching solvent. When the pH value was greaterthan 6, the concentrations of heavy metals remained at a low level. The leaching characteristics of heavymetals could be well controlled through adjusting the pH in a desired range.5) Chemical speciation and distribution of heavy metals varied greatly. Pb, Zn, and Ni were mainlypresent in the F1 and F2 so that their leachability could be well controlled in natural environment. Onthe whole, the extraction efficiency increased as the concentration of the extractant increased, but onlyfor the third chemical fraction. This trend was due to the higher ion exchange capacity of the extractantsand formation of anionic metal species, leading to more metal species leaching out of each chemicalfraction. V. FUTURE WORK In future work carried out by comparative study of leachate composition and solid waste nature plotusing mat lab plots for the distribution analysisREFERENCES [1]. R.A. Rashid, G.C. Frantz, (1992) “MSW incinerator ash as aggregate in concrete and masonry”, J. Materials in Civil Engineering 4, 353–368. [2]. C.S. Kirby, J.D. Rimstidt, (1993) “Mineralogy and surface properties of municipal solid waste ash”, Environmental Science and Technology 27, 652–660. [3]. C.C.Wiles, (1996) “Municipal solid waste combustion ash: state-of-the-knowledge”, J. Hazardous Materials, 47 325–344. [4]. Yang, G.C.C., Tsai, C.M., (1998) A study on heavy metal extractability and subsequent recovery by electrolysis for a municipal incinerator fly ash. J. Hazard. Mater, 58, 103–120. [5]. Hsien Wen Kuo, Shu-Lung Shu, Chin-Chung Wu and Jin-Shoung Lai, (1999) “Characteristics of medical waste in Taiwan”, J. Water, Air and Soil pollution, 114, 413-421. [6]. Kyung-Jin Hong, Shuzo Tokunga, Toshio Kajiuchi, (2000) “Extraction of heavy metals from MSW incinerator fly ashes by chelating agents”, J. Hazardous Materials, 75, 57-73. [7]. Abbas, Z., Moghaddam, A.P., Steenari, B.M. (2003), “Release of Salts from Municipal Solid Waste Combustion Residues”, Waste Management, 23, 291-305. [10]. James Thomson, (2005). A Report on Alternative Treatment and Non-Burn Disposal Practices Safe Management of Bio-medical Sharps Waste in India, Tata McGraw Hill, Chapter 4, pp. 64- 222 Vol. 6, Issue 1, pp. 214-224
  10. 10. International Journal of Advances in Engineering & Technology, Mar. 2013.©IJAET ISSN: 2231-1963 67. [11]. Xiao Wan, Wei Wang, Tummin Ye, Yuwen Guo, Xingbao Gao,(2005) “A study on the chemical and mineralogical characterization of MSWI fly ash using a sequential extraction procedure”, J. Hazardous Materials, 137, 197-201. [12]. T. Jeremy and A. Honor( 2005) “The Health Effects of Waste Incinerators,” The 4th Report of The British Society for Ecological Medicine Moderators. [13]. S. V. Manyele, “Toxic Acid Gas Absorber Design Con-siderations for Air Pollution Control in Process Indus-tries,” Educational Research and Review, Vol. 3, No. 4, 2008, pp. 137-147. [14]. M.Y. Wey, K.Y. Liu, T.H. Tsai, J.T. Chou, (2006) Thermal treatment of the fly ash from municipal solid waste incinerator with rotary kiln, J. Hazard. Materials. B137, 981–989. [15] Jean-François Viel, Marie-Caroline Clément, (2008) “Dioxin Emissions from a Municipal Solid waste Incinerator and Risk of Invasive Breast Cancer: A Population-based Case-control Study with GIS-derived Exposure”, International Journal of Health Geographics [16]. Kuen-ShengWanga, Kae-Long Linb, Ching-Hwa Lee (2009) “Melting of municipal solid waste incinerator fly ash by waste-derived thermite reaction”, Journal of Hazardous material (162) 338–343. [17]. Jun Yao et.al, (2012) “Heavy metals and PCDD/Fs in solid waste incinerator fly ash in Zhejiang province, China: chemical and bio-analytical characterization”, Environmental Monitoring and Assessment , Volume 184, Issue 6, pp 3711-3720. [18]. Tobias Walser, Ludwing.K limbach et.al (2012) “Persistance of engineered nano particles in municipal solid waste,” Nature of Nanotechnology. [19]. Mingjiang Ni, Yingzhe Du, Shengyong Lu, Zheng Peng, Xiaodong Li,Jianhua Yan, Kefa Cen,(2012) “Study of ashes from a medical waste incinerator in China: Physical and chemical characteristics on fly ash, ash deposits and bottom ash” Environmental Progress & Sustainable Energy, DOI: 10.1002/ep.11649AUTHORSN. Nagendra Gandhi, Head and Professor in Chemical Engineering, A.C Tech Campus, AnnaUniversity Chennai, India. So far published 40 plus papers in national and internationaljournals. He got several times best paper award. He is reviewer of many International Journals.He carried academic responsibilities like Controller of Examinations, Nodal-Officer, TEQIP-ACT, Placement and Training officer, Co-ordinator, Counselling Cell for Higher Studies, Co-ordinator, Distance Education, Co-ordinator, NBA accreditation, Chief- Superintendent,University Examinations, Co-ordinator, Entrance Exams for External Agencies, AnnaUniversity. He is invited keynote lecturer for Hydrotropy- A novel and cost effective method of liquid-liquidExtraction- Kyung Hee University-South Korea(2007), Computer Assisted Language Learning (CALL)-KyungHee University-SouthKorea(2007), Novel separation Techniques-Arunai Engineering college-Tiruvannamalai(2008), Higher studies opportunities for chemical Engineers in India and Abroad, SriramEngineering College, Chennai(2010),Higher studies opportunities for Engineers and Technologists in India andAbroad ,Sri Venkateswara Engineering College (2001).He is guiding several Phd and M.Tech students.P. Arunraj was born on 1st July 1985 at Neyveli, Tamil Nadu, India. He received B.Tech inIndustrial Bio-Technology from Government College of Technology, Coimbatore in 2006.From July 2006 - May 2007 he worked as Junior Research Fellowship in Alagappa TechCampus - Anna University Chennai. He graduated in M.Tech in Environmental Science &Technology during June 2007 - May 2009 from A.C Tech Campus - Anna University Chennai,Tamil Nadu. After that (May 2009 - Jan 2010) he worked as Freelancer Consultant in Carbon 223 Vol. 6, Issue 1, pp. 214-224
  11. 11. International Journal of Advances in Engineering & Technology, Mar. 2013.©IJAET ISSN: 2231-1963trading & Environmental Auditing. From 2010 to now he is working as Associate in Cognizant TechnologySolutions, Coimbatore, Tamil Nadu, India.R. Thirumalai Kumar was born on 20th December 1982 at Shenkottai, (Mathalamparai-HomeTown) TN, India. He received B.Tech in Chemical Engineering at Adhiyamaan College ofEngineering, Hosur 2005. From July 2005 he has been worked as Senior Process engineer inKwality Milk Foods Limited. In the year 2007 he was joined M. Tech in Petroleum Refiningand PetroChemicals completed in the year 2009 from A.C Tech Campus-Anna UniversityChennai, TN. After that (2009) he has been worked as Process Engineer-Project in C2CEngineering, Chennai, India. From 2010 to till now he is working as Senior Lecturer in theDepartment of Oil and gas engineering at All Nations University College, Koforidua (E/R), Ghana. West Africa. 224 Vol. 6, Issue 1, pp. 214-224

×