Issue 4, November 2012

 

BIODEGRADATION OF PRE-TREATED LOW DENSITY

POLYETHYLENE SPENT SALINE VIALS BY SELECTED

ARTHROBACTER SPP.

 

Carol Pereira1,2, Karpagam2, Samuel Jayasurya Kingsley1, Vincent Savariar2

 1Department of Plant Biology and Biotechnology, School of Life-Sciences

Loyola College, Chennai-34, TamilNadu, SouthIndia

INDIA

Email: candrolin@gmail.com, kingsleyvidi@gmail.com

 2P.G & Research Department of Adv. Zoology and Biotechnology

School of Life Sciences, Loyola College, Chennai-34

INDIA

Email: svincentloyola@gmail.com

 ABSTRACT

 The biodegradation of spent saline bottles, a low-density polyethylene product (LDPE) by two selected Arthrobacter sp. is reported in vitro conditions. Chemical and UV pretreatment play a vital role in enhancing the rate of biodegradation. Treated LDPE films exhibit a higher weight loss and density when compared to untreated films. Arthrobacter oxydans and Arthrobacter globiformis grew better in a medium containing pretreated films than in medium containing untreated films. The decrease in density and weight loss of LDPE was also more for pretreated film when compared to untreated films indicating the effect of abiotic treatment on mechanical properties of LDPE. The decrease in the absorbance corresponding to carbonyl groups and double bonds that were generated during pretreatment suggest that some of the double bonds were cut by Arthrobacter species. Since Arthrobacter sp.is capable of degrading urea, splitting of urea group were also seen in FTIR spectrum indicating the evidence of biodegradation after microbial incubation. The results of this study indicated that biodegradation rate could be enhanced by exposing LDPE to calcium stearate (a pro-oxidant), which acts as photo inducer of UV irradiation. The present plastic disposal trend of waste accumulation can be minimized with this promising eco-friendly technique.

Keywords: Plastic, Calcium stearate, UV irradiation, Pro-oxidant solution, Biodegradation Arthrobacter oxydans, Arthrobacter globiformis

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VALUE ADDITION TO THE LOW GRADE IRON ORE REJECTS

 

Rajashri Karmalia,b, Vrinda Borkera*, Koyar Raneb & Chandrakant G. Naikc

 aDhempe College of Arts and Science, Panaji Goa, 403001, INDIA

*Phone: +9108322462376, Email: borkarvp@gmail.com

bRani Chennamma University, Belgaum 591156, INDIA

 cNational Institute of Oceanography, Goa, 403004, INDIA

ABSTRACT

 The iron ore rejects that are usually thrown away after mining create environmental pollution. In the present study, they are used to degrade organic dyes. Methylene Blue (MB) is taken as a representative dye. The mechanism of photo degradation is similar to the photo-Fenton mechanism of degradation of organic substrates using Fe+2 and H2O2. Photo-mineralization of MB is carried out under ordinary sunlight of intensity 300 – 724 lux. The decrease in the intensity of absorbance maximum of MB is estimated using UV-Visible spectroscopy at definite intervals of time. On complete decolourization the products formed are nitrates, sulfates and CO2. COD studies also confirm the degradation of the dye. The fragments remaining after degradation are analyzed using ESI-MS studies. Complete degradation of the MB chromophore is also observed on addition of 10 mg of ore reject to the dye solution and heating it at 60°C. Photo-mineralization efficiency of the ore reject is not altered after its use. Thus the rejects are being given value addition by using them as a technologically important material.

Keywords: Iron ore Rejects, Photo degradation, Methylene Blue, Photo-Fenton reaction, Mineralization, Mining

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VERMICOMPOSTING OF VEGETABLE

AND FRUIT WASTES—EFFECTS OF BIOAUGMENTATION

ON PROCESS PARAMETERS AND MANURAL VALUE

OF COMPOSTS

 

Susila Sugumar

Department of Environmental Biotechnology, School of Environmental Sciences

Bharathidasan University, Trichy, 620 024, Tamilnadu, INDIA

Ackmez Mudhoo

Department of Chemical and Environmental Engineering

University of Mauritius, Réduit, Mauritius

Seetha Ganesan, Karthiga Arumugam, Aasha Madiq Ravi, Vasanthy Muthunarayanan*

Department of Environmental Biotechnology, School of Environmental Sciences

Bharathidasan University, Trichy, 620 024, Tamilnadu, INDIA

ABSTRACT

 In this study, the influence of Panchagavya (a liquid mixture of cow dung, cow urine, waste milk, curd, ghee, sugarcane juice, tender coconut milk, fresh banana fruits and toddy) as a source of microbes on the microbial degradation of vegetable and fruit wastes during vermicomposting has been monitored. pH, electrical conductivity, moisture content, total organic carbon, total Kjeldahl nitrogen, carbon to nitrogen ratio and the bacterial population of the resultant composts were analyzed. The vermicomposts were also subject to Fourier Transform Infrared Spectroscopy analyses to determine the degree of stabilization of the organic matter. The pool of results collectively indicated that Panchakavya succeeded in enhancing the microbial decomposition and mineralization of wastes during the composting experiments.

 Keywords: Vermicomposting, bioaugmentation, stabilization, Panchagavya

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ESTIMATION OF HOUSEHOLD WASTE

GENERATED IN GABORONE CITY COUNCIL

 

L. Gabaitiri, D.K. Shangodoyin, K. Setlhare, K. Sediakgotla

 Department of Statistics

University of Botswana

Private Bag UB00705, Gaborone

AFRICA

 Email: gabaitil@mopipi.ub.bw

 ABSTRACT

       The geometric rate at which wastes are being generated in Gaborone is alarming. This could be catastrophic if a well monitored waste management is not in place. To this end, dynamic system estimation (DSE) will provide the necessary scientific impetus for an effective waste management system. Specifically therefore, this study is aimed at providing an insight into waste generation, monitoring and control. The study objectives are to estimate the volume of solid waste generated per household per week in Gaborone City Council and compare the solid waste rates of the communities in Gaborone City Council.

We estimated that the overall average weekly household waste generated is around 7.25kg per household in the studied enumeration areas; this results into 8.34kg per household per week in Gaborone City Council. The level of waste generated weekly is more dependent on the number of people living within the household.

 Keywords: Waste, waste management, household, enumeration area

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EVIDENCE FOR WASTE MINIMISATION CLUBS AND BUSINESS

SUPPORT AS INTERVENTIONS TO PROMOTE WASTE PREVENTION

 

Paul S. Phillips1,David Parker2, Helmut Sengstschmid2, Vanessa Fandrich3

 1School of Science and Technology, University of Northampton, Northampton NN2 6JD, UK

Email: paul.phillips@northampton.ac.uk

 2Oakdene Hollins, Pembroke Court, 22-28 Cambridge Street, Aylesbury, HP20 1RS, UK

 3Systain Consulting GmbH, Spaldingstr.218, 20097 Hamburg, GERMANY

 ABSTRACT

 The Business Waste Prevention Evidence Review (Project WR1403) is a major Government funded project, in England, to map and collate available evidence on business waste prevention so as to guide future policy development. The total number of reports and documents reviewed was 971. The prime focus of research was the UK with 306 reports, but around one third of the reports (142) were sourced from outside the UK including USA, Germany, France, Australia, New Zealand, Canada and Finland as well as OECD and pan-European communities. Some 6 illustrative `sectors` were chosen for review and 8 types of interventions were examined. Central interventions include attitudes and behaviour in business and interventions by external funders as well as approaches taken to waste prevention. The Review has made clear what is known about the success factors for business waste prevention. Despite over 15 years of activity in England in business support for waste prevention, often through Resource Efficiency Clubs (RECs), there are still large gaps in knowledge, about barriers and success factors that require detailed research in areas such as RECs and business support. The Review occurred, in a period of financial constraint and there is a clear need to rationalise business support, via Best Practice Programmes, essentially for cost savings. The funding support for key Best Practice Programmes has been reduced by over 80% and not replaced with anything comparable in scope and size. This is at a time when very significant potential financial savings, from no or low cost resource efficiency actions in businesses, have been made apparent; being up to £55 billion per annum. This Review provides the evidence base required to stimulate new and dynamic approaches to funding business support for waste prevention so as to move towards achieving a high proportion of the potential savings.

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IMPACT OF LONG TERM (9 YEARS) DEPOSITION OF ANIMAL WASTES

ON SOIL PHYSICAL PROPERTIES IN ABEOKUTA,

SOUTH-WESTERN NIGERIA—IMPLICATIONS FOR SOIL

MANAGEMENT

 

M.A. Busari*, J.O. Azeez, O.O. Orelaja

 Department of Soil Science and Land Management, University of Agriculture,

PMB 2240, Abeokuta, Nigeria

AFRICA

  *Tel: +234 803 2189381; Fax: +234-39243045

Email: busamut@yahoo.com

 ABSTRACT

 Soil profile pits were examined to evaluate the effects of deposition of animal wastes on some soil physical properties. One profile pit each was dug at pig, cattle, sheep and poultry waste dump sites and one at a control site in an area where animal wastes have not been disposed of. It was observed that soil bulk density was significantly lower at animal waste dump sites than non-dump site but a saturated hydraulic conductivity (Ks) of 1.27 cm min-3 at the non-dump site was significantly higher than Ks of 0.30 – 0.88 cm min-3 obtained at all the animal waste dump sites, probably due to creation of water repellent property as a result of long term large quantity deposition of animal wastes. At the surface layer (0-20 cm) of the soil profiles, a clay dispersion ratio (CDR) of 9.5% at the control site was significantly higher than that of 6.9 – 9.3% obtained at animal waste dump sites, implying higher microaggregate stability at the surface of the dump sites. Similarly, poultry waste had significantly lowest CDR (6.9%) and highest Ks (1.16 cm min-3) than other animal wastes at the uppermost soil layer. Therefore, accumulation of animal wastes should be avoided by spreading them evenly on farm land intended to be used for future crop husbandry.

Keywords: Animal waste; microaggregate stability; soil physical properties; soil profile; water repellent

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PROPOSAL OF AN ESTIMATION METHOD OF THE DISTRIBUTION OF

THE WASTE LAYER AND CONTAMINATED GROUNDWATER

USING AN ELECTRICAL RESISTIVITY SURVEY FOR REMEDIATION OF

ILLEGAL DUMPING SITES

 

Takuya Wada, Toru Furuichi, Kazuei Ishii*

 Faculty of Engineering, Hokkaido University

N13, W8, Kita-ku, Sapporo, Hokkaido, 060-8628

JAPAN

 Email: k-ishii@eng.hokudai.ac.jp

ABSTRACT

Proper countermeasures are needed for remediation of illegal dumping sites of hazardous materials; such countermeasures should be based on the distribution of both the waste layer and contaminated groundwater. However, because of limitations in the number of borehole points, the precise distribution of the waste layer and contaminated groundwater cannot be enough determined only by conducting conventional bore exploration. On the other hand, a low-resistivity area obtained by the electrical resistivity survey can detect both the waste layer and contaminated groundwater. However, distinguishing between the waste layer and contaminated groundwater is impossible by the resistivity survey alone because the resistivity is a relative value. This study proposes an estimation method of the distribution of both the waste layer and contaminated groundwater in illegal dumping sites so that the limitations of each investigation method could be compensated. Especially, this study introduces analysis of geological characteristics such as the permeability of soils around the waste layer to distinguish between the waste layer and contaminated groundwater. As a result of applying our method to three actual illegal dumping sites, the distribution of both the waste layer and contaminated groundwater was estimated separately.

Keywords: Illegal dumping sites, distribution of waste layer, distribution of contaminated groundwater, electrical resistivity

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STRUVITE FORMATION IN LEACHATE RECIRCULATION PIPES

OF BIOREACTOR LANDFILLS


M.K.P.T.Somathilake

Department of Civil Engineering, University of Calgary

2500 University Drive NW, Calgary, AB, T2N 1N4

CANADA

Email: mksomath@ucalgary.ca

J.P.A. Hettiaratchi, Professor

Department of Civil Engineering, University of Calgary

2500, University Drive NW, Calgary, AB, T2N 1N4

CANADA

Email: jhettiar@ucalgary.ca

ABSTRACT

 A primary operational issue associated with bioreactor landfills is the potential clogging of leachate recirculation pipes due to the formation of deposits. Studies on calcium carbonate formation have been performed in the past. Struvite (MgNH4PO4.6H2O) is a chemical precipitate reported as a widespread problem in the wastewater industry. This study presents results from laboratory experiments conducted to investigate the possibility of Struvite scale formation in leachate recirculation pipes. Two types of pipes, HDPE (High-Density Polyethylene) and PVC (Polyvinyl Chloride), were tested under three different flow rates using simulated leachate. Significant reduction in concentrations of magnesium, total phosphorous, and ammonium-nitrogen were observed when simulated leachate was passed through the test pipes. The crystal structure and composition of the deposits after each experimental run were monitored and found to closely match that of Struvite. The highest scale deposition was observed for the low flow rate, irrespective of the pipe material. HDPE pipe exhibited less accumulation during high and medium flow rates than the PVC pipe. In the case of the low flow rate, the highest accumulation was in the HDPE pipe.

Keywords: bioreactor landfills, leachate recirculation, pipe clogging, Struvite

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Issue 3, August 2012

GROUNDWATER CONTAMINATION AT WASTE DISPOSAL SITES

AT IBADAN, NIGERIA

 

 Awajiogak Anthony Ujile1*, Omoleomo Olutoyin Omo-Irabor2, Joel Ogbonna3

 1Department of Chemical/Petrochemical Engineering, Rivers State University of Science and Technology

 P.M.B. 5080, Port Harcourt, NIGERIA

Email: ogakujile@yahoo.com, Tel: +2348033398876

 2Department of Geology, Delta State University

P.M.B. 1, Abraka, NIGERIA

Email: omoomoirabor@yahoo.co.uk, Tel: +2348073602126

3Department of Petroleum and Gas Engineering, Faculty of Engineering

University of Port Harcourt, NIGERIA

Email: ogbonna.joel@yahoo.com, Tel: +2348037099211

ABSTRACT

 A study was carried out to determine groundwater contamination levels on waste disposal sites of Ibadan city center in Nigeria. The surface areas of the sites vary between 23.5ha to 3.5acres. The field investigation included surface geological, hydrogeochemical and geochemical studies on the study area. Water samples were collected at 18 points. Three observation wells were dug in front of the open waste disposal site. Soil samples from these observation wells were collected at 15, 35 and 75 cm depths, and some heavy metals were analyzed. The results obtained show that concentrations of lead, copper and zinc in soil at the depth of 150 cm decreased with distance from the waste disposal site. The closest well to the waste site showed higher contamination than the control sites. Strictly speaking, use of groundwater drawn from wells located in proximity of the waste dumping sites should be avoided. If precautions are not taken, these contaminants may well spread with groundwater and pollute other soil resources used for agriculture in Ibadan.

Keywords: Heavy metals, leachate, groundwater contamination, Ibadan

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INVESTIGATION OF BIOGAS TRANSPORT IN HYDROPHOBIC

PERMEABLE MEDIUM FOR BIOCELLS

 

 Qasaimeh Ahmad1, Elektorowicz Maria2, and Jasiuk Iwona3

 1Department of Civil Engineering, Jerash University, Jerash, JORDAN

 2Civil and Environmental Engineering Building, Concordia University

1455 Boul. de Maisonneuve W, Montreal, PQ, H3G 1M8, CANADA

 3Mechanical and Industrial Engineering, College of Engineering

University of Illinois at Urbana-Champaign Urbana, IL 61801-2906, USA

ABSTRACT

At landfill, methane and carbon dioxide migrate hysterically in porous media in/and around landfill. To control biogas migration in landfill, new permeable medium in this research is proposed for biocell landfills. The permeable hydrophobic polymer medium used in this research repels water, contains more than 90 % air, and thus provides highly permeable medium for gas transport. Styrofoam has been tested as hydrophobic polymer to find its physical properties for gas conveyance. The test procedure involves investigation for permeability coefficient of polymer medium, conductivity coefficient and diffusion coefficient of carbon dioxide and methane in polymer medium. Carbon dioxide and methane convective flow rate and diffusive flux through polymer medium are tested. The influence of water content, porosity, and temperature on gas diffusion and convection are also tested. The findings of this research show that the hydrophobic dump material can be recycled as highly permeable and suitable medium for biogas collection and control in biocells.

Keywords: Biogas collection, hydrophobic permeable medium, biogas control, biocells

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RECYCLING JAROFIX WASTE AS A CONSTRUCTION MATERIAL FOR

EMBANKMENT AND SUB GRADE

 

 A.K. Sinha*1, V.G. Havanagi1, V.K. Arora2, A. Ranjan1, S. Mathur1

1Scientist, Central Road Research Institute, New Delhi, INDIA 110020

2Professor, National Institute of Technology, Kurukshetra, INDIA 136119

ABSTRACT

Jarosite is a waste material produced during extraction of zinc ore concentrate by hydrometallurgy operation. When it is mixed with 2 % lime and 10 % cement, the resulting stable material is called Jarofix. The annual production of Jarofix material is about 0.5 million tons from Hindustan Zinc Ltd., Chittorgarh, Rajasthan state, India. The unutilized accumulated material is about 1.5 million tons. The material was collected from the disposal area and laboratory investigations were carried out to study its feasibility for use in the construction of embankment and sub grade layers of road pavement. Apart from studying the material individually, it was also mixed with local soil and bottom ash in the range of 25 to 75 % and their geotechnical characteristics were evaluated. This paper presents the results of physical, chemical and geotechnical characteristics of Jarofix, Jarofix-soil and Jarofix-bottom ash blends. Technical specifications have been developed for the utilization of Jarofix material in the construction of embankment and sub grade layers of road pavement. The paper also presents the results of design and stability analysis of 5 m high Jarofix, Jarofix-bottom ash and Jarofix-soil embankment which is proposed to be constructed along a State Highway running nearby waste producing industry, Hindustan Zinc Ltd. Chittorgarh, Rajasthan. Pavement design details using Jarofix-soil mix as a sub grade material is also presented. It was concluded that Jarofix (100 %), Jarofix-soil mixes (50-75%) and Jarofix- bottom ash mixes (50-75%) have the potential for the construction of road embankment while the Jarofix-soil and Jarofix-bottom ash mixes (50-75%) may be used for construction of sub grade layer of road pavement.

Keywords: Jarofix; Waste; Material; Construction; Embankment; Sub grade

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CHEMICALLY STABILIZED CLAY CONTAMINATED BIOSOLIDS

AS COMPACTED LANDFILL LINERS

 

 Lakshika Goonewardena*, Roger Wrigley, Robert Edis, Kithsiri Dassanayake

 School of Land and Environment

The University of Melbourne

Bldg. 142, Cnr. Tin Alley and Royal Pde, Parkville, 3010, Victoria

AUSTRALIA

ABSTRACT

The landfill liners which protect the underlying soil and groundwater are normally made up of compacted clay or geosynthetic materials. These are expensive and also associated with number of shortcomings. Therefore, investigations on alternative liner material are important to prevent land and groundwater contaminations due to land filling.

A series of laboratory tests (index properties, linear shrinkage characteristics, cation exchange capacity, compaction characteristics, and hydraulic conductivity) were conducted on biosolids to assess whether they could be compacted as hydraulic barriers in waste disposal landfills. The hydraulic conductivity requirement was not satisfied although the rest of the properties were at acceptable level. Therefore, the second phase of study was aimed in investigating how hydraulic properties of biosolids could be modified through chemical means.

The second phase of study revealed that chemically stabilized biosolids have improved physical properties compared to untreated biosolids. The addition of 4% of cement, bentonite and 12% lime was found to be sufficient to achieve the desired level of saturated hydraulic conductivity.

Findings suggest that the stabilized biosolid admixtures with lime, cement and bentonite could be potentially used in place of clay and geosynthetic materials as effective and low cost compacted landfill liner material for reducing the leachate.

 Keywords:Compacted landfill liner; stabilized biosolids; cation exchange capacity; hydraulic conductivity; linear shrinkage, index properties

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PHYSICOCHEMICAL AND BIOLOGICAL CHARACTERIZATION

OF AGROWASTE FROM GREEN COCONUT SHELL

AND ITS POTENTIAL USE IN LABORATORY ANIMAL BREEDING

 

Davi Felipe Farias1, Morsyleide Freitas Rosa2, Vânia Maria Maciel Melo1, Ana Jérsia Araújo1 Lady Clarissa Brito Rocha-Bezerra1, Ana Fontenele Urano Carvalho1*

 1Departamento de Biologia, Universidade Federal do Ceará

Av. Mister Hull s/n, Bloco 909, Campus do Pici, 60455760, Fortaleza, Ceará, BRAZIL

2Embrapa Agroindústria Tropical, Rua Sara Mesquita 2270

Pici, 60455760, Fortaleza, Ceará, BRAZIL

ABSTRACT

 This work aimed to assess physicochemical and biological properties and the functionality of the green coconut coir dust (GCCD) as bedding for laboratory animals. GCCD has excellent water retention capacity (5.39 ± 0.27 g water.g-1 sample), low density (186.52 ± 11.19 g.L-1), low contents of proteins (5.59 ± 0.27%), lipids (0.97 ± 0.04%), ash (6.20 ± 2.17%), starch (16.73 ± 0.11%), total sugars (non-detected) and soluble protein and carbohydrates (0.14 ± 0.01 and 0.50 ± 0.014 mg.mL-1, respectively) and traces of tannins (<8.35 mg.mL-1). Conversely, the GCCD contains high levels of dietary fiber (70.51 ± 3.17%). GCCD has a great variety of particles size (0.5–1.0 mm = 39.96 ± 3.88%; 0.42–0.5 mm = 10.65 ± 0.97%; 0.25–0.42 mm = 29.20 ± 2.92% and <0.25 mm = 21.85 ± 2.18%). Among the nine assessed biological activities, the total extract of GCCD showed only hemolytic activity against mice erythrocytes that was much lower than of the pine shavings. GCCD was still able to retain water (2.48 ± 0.11 g water.g-1 sample) and be resistant to autoclaving after being processed into pellets. Thus, the GCCD is viable as a bedding material, especially in tropical regions where this biomass is abundant.

Keywords: Bedding, biological properties, green coconut coir dust, laboratory animals, physicochemical properties

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TRANSFER FACTOR OF RARE EARTH ELEMENTS

FROM PHOSPHOGYPSUM AMENDED BRAZILIAN TROPICAL SOILS TO

LETTUCE, CORN AND SOYBEAN

 

 K.A.P. Oliveira1,2*,M.A.B.C. Menezes2, E. Von Sperling1,  V.M.F. Jacomino2

 1Department of Sanitary and Environmental Engineering

Federal University of Minas Gerais, BRAZIL

 2Brazilian Commission for Nuclear Energy

Nuclear Technology Development Centre, BRAZIL

 ABSTRACT

About 170 million tons of phosphogypsum (PG), a by-product of phosphoric acid factories, are annually produced worldwide and agricultural use approximately 15% of this product. In Brazil, this material has been used for several decades, mainly in cerrado region (Brazilian low vegetation ecosystem). Nevertheless, such material may contain several toxic elements as radionuclides and rare earth elements (REE) which can be transferred to soil, plants and water sources. This work studied the REE transfer factor (TF) from the PG amended soil to lettuce, corn and soybean. The determination of REE concentration in all samples has been conducted by neutron activation analysis. The main REE present in PG samples was Ce (1730 mg.kg-1), followed by La (973 mg.kg-1). The main REE in clayey soil was Ce (148 mg.kg-1), followed by La (62 mg.kg-1). Sandy soil showed Ce (21 mg.kg-1), followed by Sc (6.6 mg.kg-1). REE TF from clayey soil to soybean was 0.0005 of La and 0.001 of Sc when sandy soil was used. TF from soil to lettuce was 0.003-1.1 of La and 0.001-0.01 of Sc. This paper aims to help the authorities to regulate PG use in tropical agriculture.

Keywords: Transfer factor, rare earth elements, waste management, phosphogypsum, soil amendment, neutron activation analysis.

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STRENGTH ASSESSMENT AND COMPOSITIONAL ANALYSIS

OF LIME STABILIZED FLY ASH

AND MINE OVERBURDEN MIXES UPON CURING

 

 Banita Behera*, Manoj Kumar Mishra

 Department of Mining Engineering, National Institute of Technology, Rourkela, INDIA

Ph: 91 661 246 2602, Fax: 91 661 2462022, Email: mkmishra@nitrkl.ac.in

ABSTRACT

Safe disposal of fly ash that is generated in huge quantities from fossil fuel burning is a major problem globally in general and in India particular. Several attempts exist to augment its beneficial use. An attempt has been made to utilize this material for mine haul road construction. Indian fly ash needs an activator to enhance the pozzolanic properties. In the present study, a series of laboratory unconfined compressive strength (UCS) tests and California Bearing Ratio (CBR) tests were carried out to investigate the effect of lime on strength behaviour of fly ash – mine overburden mixes upon curing. Scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) analyses were conducted at 28 days cured specimens. Addition of lime and curing of samples generally increased the compressive strength and CBR values. Empirical models were developed to correlate the CBR and UCS test results with CaO content as well as CaO/SiO2 and CaO/(SiO2 + Al2O3) ratio of the mixes. A paired t-test was conducted to evaluate the effect of chemical composition on observed compressive strength and bearing ratio values.

Keywords: Curing; Fly ash; Lime; Overburden; California bearing ratio; Chemical composition

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Issue 2, May 2012

ROLE OF PAECILOMYCES IN WASTE MANAGEMENT

Satyawati Sharma*

Kalpana Arora 

Centre for Rural Development and Technology

Indian Institute of Technology

Hauz Khas, New Delhi, 110016

INDIA

Email: kalps.arora@gmail.com

ABSTRACT

Rapid urbanization, industrialization and globalization are exerting a severe pressure on the environment through many ways including production of huge quantities of organic solid waste. Hence the environmental problems have emphasized for better utilization of waste for various purposes involving suitable cost-effective technologies. There are number of bioinoculants (efficient microorganisms as Paecilomyces, Trichoderma, Penicillium, Azotobacter etc.) which could be suitably employed for various applications using biowaste. Further if they are used in combinations, their synergistic effect may yield fruitful results. However their growth under uncontrolled conditions, to harness their potential for different applications including waste management is important. The present paper deals with the study of growth parameters of Paecilomyces under different environmental conditions (different ranges of temperature, pH and humidity), its interaction among other bioinoculants and utilizing it as an efficient microbe for rapid composting. The comparison of the parameters related as EC, pH, total organic carbon, total kjeldhal nitrogen, potassium, cellulose, hemicelluloses, lignin etc have been studied during composting, with and without inoculating Paecilomyces as bioinoculant.

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ESTABLISHMENT AND GROWTH OF VETIVER GRASS

EXPOSED TO LANDFILL LEACHATE

 

 

1Dr. A.M.S. Nyomora

College of Natural and Applied Sciences, University of Dar es Salaam

P.O. Box 35060, Dar es Salaam, Tanzania

Tel: +255754478021; Fax: +255222410379; Email: nyomora@amu.udsm.ac.tz 

Prof. K.N. Njau

Nelson Mandela Institute of Science and Technology

School of Life Sciences and Bio-Engineering (LSBE), P.O. Box 447, Arusha, Tanzania

Tel: +255 272 555070 ; Fax : +255 272 555071 ; Email: knjau30@yahoo.com 

Mrs. L. Mligo

College of Natural and Applied Sciences, University of Dar es Salaam

P.O. Box 35060, Dar es Salaam, Tanzania

Fax : +255 222 410379 ; Email : luthmligo@yahoo.com

 

  

Abstract 

Solid waste dumpsites in Dar es Salaam city are of environmental concern due to their associated leachate release into aquatic systems. They pose health risks to the Dar es Salaam residents due to the environmental pollution they cause. Currently, no control measures are employed. An effort to control leachate from Vingunguti dumpsite in Dar es Salaam using vetiver grass is in progress. Effectiveness of vetiver grass to control soil erosion and to treat wastewater is well researched; however, limited information exists on the response of vetiver grass growth to leachate and their effectiveness in phytoremediation of degraded dumpsites. This study aimed at assessing the survival of vetiver grass to landfill leachate so as to establish the use of vetiver grass in reclamation of dumpsites in Tanzania. Vetiver grass was subjected to various concentrations of leachate (0-50% v/v). The results showed that vetiver grass grew well only when it was exposed to leachate concentration of 10-30 (v/v) %. Above this concentration, vetiver grass growth was greatly reduced and complete death occurred at leachate concentrations of 75% (v/v) and above. Establishment and growth of vetiver grass Vingunguti dumpsite leachate would need approaches that limit the stress to young vetiver plants.

 

Keywords: Phytoreclamation, phytoremediation, Landfill leachate, Vetiveria zizanioides

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INVESTIGATION OF COMPACTION IN RECYCLED AGGREGATES FOR APPLICATION IN SUBBASE LAYER OF HIGHWAY

 

Vahid Ayan, Ph.D.

Department of CivilEngineering, Faculty of Engineering, Islamic Azad University

Islamshahr Branch, Islamshahr, Tehran, IRAN

Email: vahidayan@gmail.com 

Mukesh C. Limbachiya, Professor

Faculty of Engineering, Kingston University London

Penrhyn Road, Kingston upon Thames, KT1 2EE, London, UNITED KINGDOM

Email:m.limbachiya@kingston.ac.uk

Seyed Masoud Nasr Azadani, Ph.D.

Department of RailwayEngineering, Iran University of Science & Technology

Narmak, 1684613114, Tehran, IRAN

Email: Azadani@iust.ac.ir

Joshua R. Omer, Ph.D.

Faculty of Engineering, Kingston University London

Penrhyn Road, Kingston upon Thames, KT1 2EE, London, UNITED KINGDOM

Email:j.r.omer@kingston.ac.uk

ABSTRACT

A study was recently conducted at Kingston University to assess the suitability of using recycled concrete aggregate (RCA) and reclaimed asphalt pavement (RAP) in unbound subbase mixtures. The results show that the use of 100% recycled aggregates increased the optimum moisture content and decreased the maximum dry density of the subbase materials in comparison with natural aggregates. Moreover, the replacement of recycled concrete aggregates by reclaimed asphalt pavement by 50% decreased the optimum moisture content and increased the maximum dry density in proportion to 100% RCA. The CBR values of the subbase materials prepared with 100% RCA is lower than subbase mixture with 100% natural aggregates. The CBR further decreased for replaced subbase with RAP. For the achieved water range in each mix the trend of CBR investigated within dry density.

 

Keywords: Recycled concrete aggregate, Reclaimed Asphalt Pavement, Unbound Subbase, CBR, Compaction

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FLEXURAL STRENGTH OF LAMINATED WASTE CONCRETE— NORMAL CONCRETE BEAMS

 

Samy Antit*, Ph.D. Student

Laboratoire de Génie Civil, Ecole Nationale d’Ingénieurs de Tunis

BP 37, le belvédére, 1002 Tunis, Tunisia

Email: samyantit@gmail.com

Hédi Hassis, Professor

Laboratoire de Génie Civil, Ecole Nationale d’Ingénieurs de Tunis

BP 37, le belvedere, 1002 Tunis, Tunisia

Email: hedi.hassis@enit.rnu.tn

Bruno Fiorio, Associate Professor

Laboratoire de Mécanique et Matériaux du Génie Civil

Université de Cergy-Pontoise, 33, bd du port F95011 CERGY-PONTOISE Cedex, FRANCE

Email: bruno.fiorio@u-cergy.fr

ABSTRACT

The wide production of construction and demolition waste and its illegal deposition are serious current problems in Tunisia and worldwide. This study is a contribution to a Tunisian national program held to promote the utilization of Construction and Demolition Waste (C & D waste). It is focused on the evaluation of the possibility of reusing C & D waste aggregate (Debris of masonry) as a substitute for natural aggregate to produce “waste concrete” used in structural application such as beams. This paper investigates the flexural behaviour of three types of reinforced concrete (RC) beams: full normal concrete beams, full waste concrete beams and laminated beams (waste concrete / normal concrete beams).

Both “waste concrete” and “waste aggregates” are characterized to optimize the physical and mechanical properties. The influence of this substitution on the compressive strength, the tensile strength and the structural behaviour of this material was studied.

Four points bending tests were carried out on laminated beams and the experimental results are compared to full waste concrete beams and full normal concrete beams. Flexural behaviour of the laminated beam compared to full normal concrete beam shows good performance. As the waste concrete is confined to the tensile zone of the laminated beam and does not affect the strength of the compressive zone of the beam, the strength loss (usually 15 to 20%) due to replacing the normal concrete by the waste concrete can be in this case reduced and make possible the use of recycled waste aggregates in concrete for structural application (beams).

 

Keywords: Construction and Demolition Waste (C & D waste); debris of masonry; recycled aggregates (RA); waste aggregate (WA); natural aggregate (NA); waste concrete (WC); laminated beams.

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REUSE OF SLAGS CONTAINING LEAD AND ZINC AS AGGREGATE IN A PORTLAND CEMENT MATRIX

 

Giorgio De Angelisa and Franco Medicib

aENEA, Technical Unit for Fission Technologies and Plants and for the Nuclear Material Management, Casaccia Research Centre, Via Anguillarese 301, 00123 S. Maria di Galeria, Roma, ITALY

Email: giorgio.deangelis@enea.it

bDepartmentof Chemical Engineering Materials and Environment, “Sapienza” University of Roma

Via Eudossiana 18, 00184 Roma, ITALY

Email: franco.medici@uniroma1.it

ABSTRACT

      Both economic and environmental reasons force research activities to find valid alternatives to the disposal of high quantities of metal containing slags. One of the most promising routes seems to be the exploitation of slags as inert materials for cement conglomerate: to this end a preliminary characterization of slags arising from lead/zinc pyrometallurgical smelting (ISF) and lead batteries recycle (LBR) was made anddifferent slag-Portland cement mixes were prepared with an increasing waste content.

      Heat evolution has been determined and a series of tests on the final waste forms have been conducted in order to evaluate the mechanical performance and the leaching behaviour. In spite of the acceptable mechanical characteristics for both slag-cement products, a high release of lead represents a serious problem.

      The conclusion is drawn that if preliminary extraction of the main pollutants from the raw slags is unpractical, just a limited amount of slags can be incorporated in cement. At the same time the adoption of other stabilization techniques should be taken into account.

 

Keywords: Slags, lead, zinc, cement, leaching, recycling

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FEASIBILITY STUDY OF AN INVERTED T PIPE

FOR PASSIVE AERATION COMPOSTING

 

G.A. Ogunwande*, L.A.O. Ogunjimi, J.A. Osunade

Department of Agricultural & Environmental Engineering

Obafemi Awolowo University

Ile-Ife, NIGERIA

ABSTRACT 

Passive aeration composting was carried out in chicken litter piles equipped with a conventional horizontal pipe, a vertical pipe and an unusual inverted T pipe. The effects of the aeration pipes on temperature, pH, electrical conductivity, moisture content, total carbon, total nitrogen, total phosphorus and carbon to nitrogen ratio of the chicken litter were monitored during composting. Moisture content of the piles was replenished fortnightly to 60%. The results of the study showed that inverted T pipe was feasible, as did horizontal and vertical pipes, for passive aeration composting as the pile equipped with it attained thermophilic temperatures and met sanitation requirements. Aeration pipe significantly (p ≤ 0.05) affected pile temperature, pre-replenishment moisture content, pH and electrical conductivity, but did not affect compost elements. Inverted T pipe was the most effective for uniform composting rate and compost quality within the pile.

Keywords: Passive aeration composting, chicken litter, aeration pipe, composting rate, compost elements

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POTENTIAL OF WATER HYACINTH

(EICHHORNIA CRASSIPES MART. SOLMS – LAUBACH)

IN RUMINANT PRODUCTION TO CURTAIL ITS ENVIRONMENTAL HAZARDS ON NIGERIAN WATER WAYS

 

A.A. Mako and V.O. Akinwande 

1Department of Agricultural Production and Management Sciences

Tai Solarin University of Education, Ijagun. Ijebu-Ode

PMB, 2118, Ijebu-Ode. Ogun State

NIGERIA

ABSTRACT

      Aquatic plants constitute a major environmental menace in Nigerian water ways, due to high proliferation rate. This study was to access the usefulness of water hyacinth (WH) for ruminant production especially during the dry season and to curtail the environmental menace caused by these plants. The proximate composition, spot test analysis for secondary metabolites and mineral analysis of morphological parts (MP) were determined. In vitro gas production of MP was carried out under 24hr incubation to estimate the metabolizable energy, organic matter digestibility, short chain fatty acids and methane (CH4) production.

      Results showed that proximate composition differ (p<0.05) amongst MP. The dry matter (DM) and crude protein (CP) ranged from 5.34 to 11.07 and 7.20 to 14.33g /100 g DM in the stem and leaf respectively. All MP contained tannins and steroids; saponin was declared negative due to the method used. Macro and micro mineral values are high, but not significant. The gas produced ranged from 17.41 to 19.53 ml/200 mg DM in the leaf and stem respectively. The metabolizable energy (ME), organic matter digestibility (OMD), short chain acids (SCFA) and CH4 differed (p<0.05).

      The nutrient composition andgas production parameters revealed that WH is high in CP suggesting its possibility of being utilized as fodder for ruminant production in the tropics.

 

Keywords: Degradation, menace, minerals, morphological parts, proximate composition, secondary metabolites

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Issue 1, February 2012

 

THEMOCATALYTIC CRACKING OF WASTE POLYETHYLENE

INTO USEFUL FUEL PRODUCTS

 

Jasmine Shah,1 M. Rasul Jan,1 Khalid Mohammed Khan,2 Zahid Hussain*1 

1Institute of Chemical Sciences, University of Peshawar

N.W.F.P, PAKISTAN

Email: drzhussain@yahoo.com

2H.E.J. Research Institute of Chemistry, International Center for Chemical Sciences

University of Karachi, Karachi-75270, PAKISTAN

Department of Chemistry, Abdul Wali Khan University

Mardan NWFP, PAKISTAN

ABSTRACT 

A new thermo catalytic method for the cracking of polyethylene was investigated. Polyethylene was converted into oil, wax and fuel gas using china clay as catalyst. The catalyst was used both in crude and activated form. The rate of reaction and the relative mass of the three fractions were found to depend upon the mass and nature of the catalyst as well as temperature. The optimum ratio of the polyethylene to catalyst was 3:1 and the temperature for maximum conversion and greater mass of liquid product was found to be 573K. At these optimum conditions the crude clay catalyzed reactions complete in thirty minutes. And the reactions for activated clay in fifteen minutes. This was explained on the basis of the structure and composition of these catalysts. The liquid and wax products were analyzed by gas chromatograph equipped with FID and infrared spectroscopy in addition to physicochemical tests. These products were found to contain aromatics, olefins and paraffin.

 

Keywords: Thermo catalytic degradation, low density polyethylene, activated china clay, fuel products

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USING SUGAR CANE BAGASSE ASH INTO CLAY PRODUCTS

 

Wilson Acchar1,2,* and Raimundo Jorge Santos Paranhos2

1Physics Department, Federal University of Rio Grande do Norte

Natal-RN, 59072-970

BRAZIL

2Postgraduate Program of Science and Materials Engineering, University of Rio Grande do Norte

Natal-RN, 59072-970

BRAZIL

ABSTRACT

The agro and industrial activities are currently responsible for the production of large amounts of solid wastes. The use of industrial wastes such as granite, marble, kaolin and pegmatite and agro-industrial rejects into clay products has been widely developed over the last few decades. Clay materials used in the ceramic industry exhibit a large diversification of compositions that allow the addition of different types of waste materials to the clay mixture. Sugar cane bagasse ash (SCBA), a by-product of the sugar process, is exacerbating the environmental problem. Brazil produces an enormous amount of sugar and the lack of adequate landfill areas available for disposal of sugar cane bagasse ash rejects poses a critical problem for the agro-industry. This work describes, for the first time, research carried out on the manufacturing of ceramic tile materials with sugar cane bagasse ash additions. SCBA, consisting basically of potassium oxide, was added to the clay formulations as an alternative to feldspar. Clay with different sugar cane bagasse ash content was mixed and sintered. Sintered specimens were characterized by X-ray diffraction, density, porosity, thermal analysis and strength measurements. The results obtained showed that the sugar cane ash residue can be added to clay materials as an alternative to feldspar, without degrading their properties.

 

Keywords: Sugar cane bagasse, waste material, mechanical properties, clay products

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CO-DIGESTION OF TANNERY SOLID WASTES

WITH PRIMARY SEWAGE SLUDGE AND VEGETABLE WASTES

FOR BIOGAS PRODUCTION

 

B. Velmurugan* and R. Alwar Ramanujam 

Department of Environmental Technology

Council of Scientific and Industrial Research

Central Leather Research Institute

Adyar, Chennai-600020

INDIA

TEL: +91-44-24450234; FAX: +91-44-24450234

Email: tovelmurugan@gmail.com

ABSTRACT 

Anaerobic Co-digestion process is a well established technology for treating mixture of different types of organic wastes. In this preliminary work, Anaerobic digestion of Animal fleshing, Primary Sewage Sludge and Vegetable Wastes were studied separately in reactors R1, R2, R3 and co-digestion in reactors R4, R5, R6, R7 and R8 by mixing them in different proportions for a retention time of 20 days and initial organic load of 3.33 kg VS/m3 to evaluate the performance in terms of volatile solids removal and biomethanation potential of wastes The volume of the reactor used was 0.5l. Animal fleshingand vegetable waste mixed in equal proportions (0.5g : 0.5g) in terms of VS were found to be compatible for anaerobic co-digestion process with higher rate of gas production compared to animal fleshing and primary sewage sludge mixed in equal proportion in terms of VS. The influence of primary sewage sludge on biogas production was insignificant in anaerobic co-digestion process when animal fleshing and vegetable wastes were present in larger proportions in the feed as compared to the amount of primary sewage sludge.

 

Keywords: Animal fleshing, Co-digestion, primary sewage sludge, vegetable wastes

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EFFECT OF MEDICAL ASH ON SHEAR PROPERTIES OF ASPHALT BINDER USING SUPERPAVE DYNAMIC SHEAR RHEOMETER (DSR)

 

Taisir Khedaywi

Professor of Civil Engineering, Department of Civil Engineering

Jordan University of Science and Technology, P.O.Box 3030, Irbid 22110, JORDAN

Tel: + 962-2-720-1000 Ext: 22129; Cell: +962-79-558-8657; Fax: +962-2-720-1074; Email: khedaywi@just.edu.jo

Ghazi Al-Khateeb

Associate Professor of Civil Engineering, Department of Civil Engineering
Jordan University of Science and Technology, P.O. Box 3030, Irbid 22110, JORDAN
Tel: + 962-2-720-1000 Ext: 22129; Cell: +962-79-659-9507; Fax: +962-2-720-1074; Email: ggalkhateeb@just.edu.jo

Motaz Irfaeya

Graduate Research Assistant, Department of Civil Engineering
Jordan University of Science and Technology, P.O. Box 3030, Irbid 22110, JORDAN

ABSTRACT

This study had focused on the effect of medical ash mineral filler passing sieve No. 200 (0.075 mm) on the rheological shear properties of asphalt binder used for paving construction in Jordan. Mastic was prepared using medical ash mineral filler and an asphalt binder at various volume concentrations (5, 10, 20, and 30%). The Superpave dynamic shear rheometer (DSR) device was used to measure the complex shear modules for asphalt binder and mastic in frequency sweep tests. The loading frequency of the test varied from 0.10 Hz to 10 Hz using the values of (0.1, 0.178, 0.30, 0.5, 1.0, 1.78, 3.0 5.0, and 10 Hz). The DSR tests covered a wide range of test temperatures from 10°C to 70°C divided linearly into seven temperatures (10, 20, 30, 40, 50, 60, and 70°C). The main objectives of the study were (1) to utilize the Superpave Dynamic Shear Rheometer (DSR) test for studying the behavior of asphalt mastic, (2) to investigate the effect of medical ash on the shear properties of asphalt binders obtained from the DSR, and (3) to study the effect of the medical ash addition on the fatigue resistance as well as rutting resistance of asphalt binders used for roads construction in Jordan. Several behaviors of asphalt binder and mastics were discussed during this study; mainly the complex shear modulus of binder and mastics were measured and analyzed. The rutting and fatigue responses of both the asphalt-medical ash mastics and the asphalt binder were analyzed. The study also illustrated the relationship between the loading frequency and the complex shear modulus values, and discussed the effect of loading frequency and temperatures variation on the behavior of asphalt mastic.

 

Keywords: Medical Ash, Dynamic Shear, Asphalt Binder, Mastic, Superpave,DSR

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PARTIAL REPLACEMENT OF NATURAL SAND BY FLY ASH—

A SOLUTION TO FLY ASH WASTE MANAGEMENT

 

Dr. A.D. Pofale

Professor, Civil Engineering. Dept., Visvesvaraya National Institute of Technology

Nagpur, Maharashtra

Mobile: +09423681931

Email: pophalearun@rediffmail.com

Prof. S.V. Deo

Assistant Professor, Civil Engineering Dept., National Institute of Technology Raipur

Raipur, Chattisgarh

Mobile: +919713099399

Email-shirishdeo@yahoo.com

ABSTRACT 

The use of fly ash as replacement of sand is a simple solution to the fly ash waste management as it has a great potential to reduce landfill area requirement for dumping the fly ash. It also benefits our society in terms of reducing demand of scarcely available natural sand. The paper presents the results of experimental investigation, which indicated about 34% increase in the compressive strength and about 24% increase in the flexural strength of concrete by the inclusion of fly ash as 100% replacement of sand as compared to control concrete. Sand was replaced by fly ash by 20%, 40%, 60%, 80% and 100%. Results indicated increase in the workability for all the cases over control concrete. The increase in slump was about 30% over control concrete for 40% sand replacement by fly ash. Concrete with fly ash was also found to be about 33% economical when cost per N/mm2 was compared. Based on experimental results correlations are developed to predict the compressive strength, the flexural strength, cost per N/mm2, slump and dry density for percentage sand replacement with fly ash. Also correlations are developed to predict the compressive strength, the flexural strength, slump and dry density with surface index.

 

Keywords: Fly Ash; Compressive Strength; Flexural Strength; Flow; Density; Green Concrete

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Development of a Solid Waste Prediction,

Characterization, and Modeling Tool for the

Assessment of Manufacturing and Service Waste Management Systems

 

Matthew J. Franchetti

Dept. of Mechanical, Industrial and Manufacturing Engineering, University of Toledo

2801 West Bancroft Street

Toledo, Ohio USA

 

Abstract

The goal of this study was to develop an integrated solid waste prediction and evaluation model. The purposes of the model were to better quantify solid waste generation compositions in order to evaluate performance of U.S. businesses and government agencies. A review of the literature showed that predicting and evaluating solid waste generation is relevant and important to environmental regulators and businesses. In addition, most studies lacked empirical support and rigorous statistical analyses, specifically related to individual company waste generation performance. To achieve the objective of this study, an integrated environmental model was developed to predict and evaluate solid waste generation rates. Data were collected from businesses and government agencies in the United States to answer research questions and build the integrated environmental model. The results of the national survey yielded 438 responses. U.S. business and government agencies were consolidated into 20 waste generating groups using multivariable cluster analysis. Significant variables that influence solid waste generation rates were identified for the 20 waste groups using stepwise regression analysis. Waste generation rates of individual companies in these waste groups were predicted and evaluated using performance parameters developed for this research. The findings of this research offer companies and regulators an effective means to improve environmental performance and allow them to predict and evaluate waste generation rates. Using the results of the research, companies can learn more about their strengths and weaknesses in their solid waste management and can then assess their generation performance versus industry specific benchmarks.

 

Keywords: Solid waste categorization, measurement, and reporting

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FIXED-BED FIRE-TUBE HEATING PYROLYSIS OF AGRICULTURAL BIOMASS SOLID WASTE—JUTE-STICK IS AN ALTERNATIVE SOURCE OF LIQUID FUEL

 

Momtaz Parveen

Department of Mechanical Engineering, National University Corporation Kitami Institute of Technology

165 Koen-cho, Kitami City, Hokkaido 090-8507, JAPAN

Email: m_parveen90@yahoo.com

Mohammad Rofiqul Islam

Department of Mechanical Engineering, Rajshahi University of Engineering & Technology

Rajshahi-6204, BANGLADESH

Email: mrislam1985@yahoo.com

Hiroyuki Haniu

Department of Mechanical Engineering, National University Corporation Kitami Institute of Technology

165 Koen-cho, Kitami City, Hokkaido 090-8507, JAPAN

Email: harry@mail.kitami-it.ac.jp

ABSTRACT

The objective of this study is to provide a new approach in heating system for pyrolysis technology to the recovery of liquid hydrocarbons from biomass solid wastes. A fixed-bed fire-tube heating pyrolysis reactor system has been designed and fabricated. The abundantly available agricultural waste—jute stick in Bangladesh has been pyrolyzed in the internally heated fire-tube heating reactor system under N­­2 atmosphere. The effects of operating temperature, feed size and vapor residence time on the yields and compositions of product liquids were investigated. Final temperature range studied was between 375 and 575oC and the highest liquid product yield was obtained at 475oC. Characterization of the whole pyrolysis liquids obtained at optimum operating conditions has been carried out including physical properties, elemental analysis, GCV, FT-IR, 1H NMR and distillation. Characterization shows that the product bio-oils may be potentially valuable as liquid fuels and chemical feedstocks for industrial applications.

 

Keywords:Fire-tube heating; agricultural wastes; pyrolysis; liquid fuel

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