Issue 4, November 2009
DRIVING SUSTAINABLE WASTE MANAGEMENT IN NORTHERN IRELAND—HOME COMPOSTING OF “GREEN GARDEN WASTE” IN CASTLEREAGH
North Down Borough Council, Balloo Transfer Station
15A Balloo Drive, Bangor, BT19 7QY
Paul S. Phillips and Terry Tudor
SITA Centre, University of Northampton, Northampton NN2 7AL
Castlereagh Borough Council (Castlereagh BC) borders with Belfast in the east of Northern Ireland and serves a population of approximately 67,500. There are approximately 28,500 properties in the borough and 80% of households lie within urban areas. In 2007/8, Castlereagh BC had a household waste recycling and composting rate of 37.69%. In 2007/8, 19,603 tonnes of household waste was landfilled this equates to 0.69 tonnes per household. The Council actively promotes Home Composting of green garden waste as a method of waste reduction and has offered a subsidised rate on the sale of Home Composters. In order to evaluate whether this subsidisation is justified, a survey was carried out on all householders that have purchased a Home Composters. It was hoped that this survey would provide information on whether householders who had purchased Home Composters from the Council were actually using them, whilst also gauging whether householders are aware of the relationship between composting and diversion from landfill. Some 96% of respondents that purchased Home Composters are still using them. This is extremely encouraging and demonstrates that they would appear to be satisfied with their Home Composting experiences. Respondents (92%) stated that they noticed a decrease in the amount of their waste being sent for landfill/composting through the kerbside collections, this demonstrates that they are aware of the relationship between Home Composting and diversion from landfill. Some 86% of householders feel that they are using their Home Composter successfully and 93% of householders were satisfied with the scheme. However, 17% of householders complained about composter design and 16% found it difficult to use. Size, mobility and the unattached lid were of main concern. The results will be used to drive enhanced campaigns for the uptake of home composting of green garden waste.
Keywords: Home composting; Organic; Waste Prevention; Garden Waste; Landfill; Reuse
MAKING FIRED BRICKS WITH SPENT EQUILIBRIUM
CATALYST—A TECHNICAL FEASIBILITY STUDY
*Mei-In (Melissa) Chou1, 2, Lu-Ming Chen1, 2,
Yi-Chieh Lai1, 2 and Sheng-Fu (Joseph) Chou1
1Illinois State Geological Survey, Institute of Natural Resource Sustainability
University of Illinois, 615 E. Peabody Drive
Champaign IL, 61820, USA
2Department of Natural Resources and Environmental Sciences
University of Illinois, Urbana-Champaign
Champaign, IL 61820, USA
Fluid catalytic cracking in an oil refinery uses a catalyst, such as an alumino-silicate zeolite, in the conversion of heavy hydrocarbons to light hydrocarbons. A small fraction of the catalyst is continually replaced with fresh catalyst to maintain activity. In North America, more than 400 tons of spent alumino-silicate equilibrium catalyst (spent e-cat), and worldwide, more than 1,100 tons, are generated daily, most of which is disposed of in landfills (municipal and on-site facilities). In this study, three spent e-cat samples were tested in a value-added application that would utilize this waste in the manufacturing of fired bricks. The results of this study indicate that spent e-cat is a technically feasible raw material substitute for the clay and shale commonly used in fired brick production. Fired bricks produced with up to 30 wt% of spent e-cat showed good physical appearance and their water absorption properties met the ASTM C 62 specifications for building bricks of either the moderate- or severe-weathering grade.
Keywords: Spent equilibrium catalyst, brick, technical feasibility, oil refinery, solid waste
DETERMINANTS OF MUNICIPAL SOLID WASTE GENERATION AND RECYCLING IN WESTERN NEW YORK COMMUNITIES
Senior Economist, Ecology & Environment Inc., 368 Pleasant View Drive, Lancaster, NY, 14086, USA
Email: firstname.lastname@example.org, Tel: 716-684-8060, Fax: 716-684-0844)
GIS Analyst, Ecology & Environment Inc., 368 Pleasant View Drive, Lancaster, NY, 14086
Air Quality Meteorologist, Ecology & Environment Inc., 368 Pleasant View Drive, Lancaster, NY, 14086
Statistician, Ecology & Environment Inc., 368 Pleasant View Drive, Lancaster, NY, 14086
Manager of Information Resources, Ecology & Environment Inc., 368 Pleasant View Drive
Lancaster, NY, 14086
The accurate determination of waste quantities is essential for effective municipal solid waste management. This paper creates several statistical models that can be applied to predict residential municipal solid waste quantities. Using municipal solid waste data sourced from 38 towns and villages that were canvassed as part of the NorthEast Southtowns Regional Solid Waste Management Plan, several multiple regression based models were estimated that explored the determinants of annual municipal solid waste generated, recyclables, and compost (yard waste) tonnages. The first group of equations was based on panel and census data for the year 2000. Climate, demographic, socio-economic, cost and distance variables were evaluated as independent variables. For the largest town in the region (Amherst), a multiple regression based time series model was estimated that covered nine years and monthly seasons including several major storm events. The models can be used for prediction and planning purposes by solid waste managers, agencies and planners, and for comparison to other regions and countries.
Keywords: Municipal solid waste, compost, yardwaste, recyclables, waste generation, resource recovery rates, predictive models, seasonal factors, transport and disposal costs
EVALUATION OF USING RECYCLED PLASTIC LUMBER FOR BASE MATERIALS IN ROADWAY APPLICATIONS WITHIN NEW YORK CITY
Ph.D., Assistant Professor, Department of Environmental and Civil Engineering
U.A. Whitaker School of Engineering, Florida Gulf Coast University
Ph.D., P.E., Professor, Department of Civil Engineering
Grove School of Engineering, The City College of New York
Convent Avenue at 138th Street, Room T-134, New York, NY 10031
Undergraduate Research Assistant, Department of Civil Engineering
Grove School of Engineering, The City College of New York
The objectives of this study were to determine: 1) the feasibility of using recycled plastic as an effective alternative base material within the pavement system of New York City and 2) the structural adequacy of using recycled plastic in roadway applications. The literature review supports the hypothesis that waste plastic, especially in form of fiber-reinforced Recycled Plastic Lumber (RPL), can be effectively used as a roadway material. The effects of rutting and cracking with the introduction of RPL into pavement structures, was evaluated using BISAR, an elastic multi-layer computer program. A comparative approach between Portland Cement Concrete (PCC), the most typical pavement structure found in New York City, conventional Asphalt Cement Concrete (ACC) and the proposed ACC-RPL combination were evaluated. Results from this analysis showed that the stress-strain distribution along the pavement cross-section containing RPL was lower or close to the ACC and PCC pavements currently encountered in New York City. These stress-strain values in the RPL pavement structure were 90% lower as compared to a conventional ACC pavement. This information lends credence to the notion that RPL can be used as a superb material in roadway applications. Further validation and refinement of the model is continuing to more accurately determine the effect of substituting RPL as a base layer within the utility infrastructure in an urban environment such as New York City.
Keywords: Utility cuts, Recycled plastic, Recycled Plastic Lumber (RPL), Pavement structure
GROUND POLLUTION DUE TO STONE CUTTING INDUSTRY CASE STUDY—HEBRON DISTRICT
Nabil Al-Joulani, Ph.D., P.Eng.
Civil and Architectural Engineering Department
College of Engineering and Technology
Palestine Polytechnic University
Hebron Box 198, ISRAEL
In stone cutting plants, rock blocks are cut into different sizes and shapes. The cutting and shaping process is accomplished by using metal saws which need a tremendous amount of cooling water. The cooling water is discharged out of the plant as highly viscous material referred to as stone slurry waste. The stone slurry waste poses a serious environmental hazard.
This research discusses ground pollution by stone slurry waste generated by stone cutting industry in Hebron district. The study focuses on the effect of stone slurry waste on pH, Electrical Conductivity (EC), salinity and the Total Dissolved Solids (TDS) for three different types of soil (sand, Terra Rosa Clay and artificial organic soil).
The Global Positioning System (GPS) and the Geographic Information System (GIS) were used as a tool to estimate the total polluted ground in Hebron district. Spatial data and area maps were developed for the polluted areas.
The results have revealed that the pH, EC, salinity and TDS of the artificial organic soil are significantly affected by addition of different percentages of stone slurry waste up to 80%, compared to moderate and weak effect on Terra Rosa and sandy soils. Analysis of the spatial data from GPS and GIS have shown that the polluted area in Hebron district varied between 0.73% to 20.6% of the total municipal area, assuming buffer diameter of 100 meter for polluted areas.
Keywords: Ground pollution, Stone Waste, GIS, GPS
D.S. Mahamah, Ph.D., PE.
Professor of Civil Engineering, School of Engineering
Saint Martin’s University
5300 Pacific Avenue, SE
Lacey, WA 98503
Socioeconomic factors influence solid waste composition and generation. In industrialized societies, reliable socioeconomic data is often available for forecasting waste generation and composition. In most developing countries, however, solid waste generation data is often limited and unreliable. Beginning in the early nineteen eighties, the Sultan of Oman significantly invested in infrastructure such as roads, housing, and potable water following the discovery of commercial quantities of crude oil. Furthermore, the Sultanate embarked on an ambitious program of proper solid waste collection, disposal and record keeping. Hitherto comingled waste was discarded in unlined open dumps by individuals and municipalities, a practice still common in many developing countries. The Sultan dedicated resources for the construction and operation of several engineered landfills for waste disposal, aimed at curbing growing groundwater pollution and urban blight. The Governorate of Muscat is the commercial and political center of the Sultanate, and covers 3,900 square kilometers (1.2% of the land mass) of mostly hilly desert terrain on the Arabian Sea, with a population of approximately 1 million (2007). Properly designed disposal systems require reliable forecasts of future waste generation. This paper examines the relationships between socioeconomic factors such as population (POP), Gross Domestic Product (GDP), Consumer Price Index (CPI), Gross National Income (GNI), Gross Domestic Income (GDI), and solid waste generation rate (SWG) as a basis for forecasting solid waste generation in Muscat. Linear and non-linear models relating solid waste generation (SWG) and the independent variables POP, GDI, GDP, CPI, and GNI are developed and discussed.
Keywords: Solid waste, generation rate, socioeconomic indicator, statistical model
Issue 3, August 2009
DEVELOPMENT OF LIGHTWEIGHT CONSTRUCTION MATERIAL FROM ALKALI ACTIVATED FLY ASH
Hossein Rostami1, Robert Brooks
2, Fernando Tovia3, Mozhgan Bahadory4
1 Associate Professor of Science, Philadelphia University, Philadelphia PA, 19144, Phone: (215) 951-2877, Fax: (215)951-6812,
2 Associate Professor, Temple University, Philadelphia, PA 19122, Corresponding author – Phone: (215) 204-6348, Fax: (215) 204-4696,
3 Assistant Professor of Engineering, Philadelphia University, Philadelphia PA, 19144, Phone: (215) 951-5256, Fax: (215)951-6812,
4 Researcher, Resource Engine Corp, Philadelphia PA, 19104, Phone: (215) 895-1693, Fax: (215)895-1265, Email: email@example.com
A new lightweight material for construction applications that utilizes alkali activated fly ash along with a gassing agent and lightweight aggregates (e.g. vermiculite) has been developed. This Lightweight Alkali Ash Material (LW-AAM) does not require autoclaving, in contrast to the production of conventional Autoclave Cellular Concrete.
LW-AAM can produce materials with densities ranging from 1200 kg/m3 to 2200 kg/m3 and compressive strength from 2 MPa to 65 MPa. These are highly resistant to corrosive action of sulfuric, nitric, hydrochloric and acetic acids which are known to readily deteriorate Portland cement concrete. LW-AAM is also a highly durable material. It resists the action of freezing and thawing. In addition to the development of new engineering material, utilization of AAMs for construction has the potential of recycling of a huge quantity of fly ash that otherwise would be landfilled.
SCRAP TIRE—AN ATTRACTIVE MATERIAL FOR GRAVITY RETAINING WALLS AND SOIL REINFORCEMENT
Catholic University of Rio de Janeiro, Rio de Janeiro,
R. Marques de S�o Vicente 225, Room 301, 22453-900 BRAZIL
State University of Rio de Janeiro Rio de Janeiro,
R. S�o Francisco Xavier 524 – 5018 Bl A, 20550-900 BRAZIL
Catholic University of Rio de Janeiro Rio de Janeiro,
R. Marques de S�o Vicente 225, Room 301, 22453-900 BRAZIL
State University of Rio de Janeiro, Rio de Janeiro,
R. S�o Francisco Xavier 524 – 5018 Bl A, 20550-900 BRAZIL
Industrial societies produce scrap tires at increasing rates every year, generating a large amount of a non-degradable urban solid waste. Stockpiles of scrap tires are exposed to constant danger of fire, besides they may induce propagation of insects and diseases. This paper describes the construction procedures and results of a comprehensive research project on the re-use of scrap tires for geotechnical engineering purposes, carried out in Rio de Janeiro, Brazil. A 60m length prototype soil-tire retaining wall was built with layers of tires filled in with compacted soil. The wall comprised 4 sections in order to evaluate the influence of the construction procedure on the flexibility of the retaining structure. The wall and backfill were instrumented with inclinometers and earth pressure cells. A numeric simulation of the construction of the wall was used to evaluate the deformability parameters of the tire-soil material. The soil-tire interaction mechanism was studied by a series of series of field pullout tests, with several arrangements of scrap tire mats which were subjected to different confining levels. The research revealed that scrap tires are an attractive low cost construction material for slope stabilization projects.
Keywords: Scrap tires, retaining wall, field instrumentation, field pullout tests
ESTIMATING METHANE PRODUCTION POTENTIAL OF AN OLD MUNICIPAL LANDFILL
Joseph C. Akunna*, Ph.D.
Urban Water Technology Centre, University of Abertay Dundee
Bell Street, Dundee DD1 1HG, UNITED KINGDOM
Kazi Hasan, M.Sc.
Urban Water Technology Centre, University of Abertay Dundee
Bell Street, Dundee DD1 1HG, UNITED KINGDOM
Kenneth Kerr, M.Sc.
Waste Management Department, Dundee City Council
34 Harefield Road, Dundee DD2 3JW, UNITED KINGDOM
This paper presents a methodology for estimating methane potential of a closed landfill applied at a site in Dundee, Scotland. Leachate and gas monitoring data collected over a three-year period were to enable identification of areas where detailed characterisation of the buried wastes was carried out for the estimation of methane potential of the landfill. The site did not have leachate collection or recycling. It was thus assumed that in-situ leachate quality was a reflection of the nature of overlaying wastes. Five new sampling boreholes were created on this basis. Solid samples were analysed using the accelerated biodegradability test. Results showed that the organic wastes still present in the landfill were mainly non-readily biodegradable materials such as woods, plastic materials, textiles etc. with methane potential varying from 1.3 to 2.5 Nm3CH4/tonne of total dry solids. Both existing leachate quality data and those obtained from the new sampling boreholes also suggested that most readily biodegradable organic matter in the landfill had been stabilised. It was concluded that wastes remaining in the landfill would break down extremely slowly due to low the in-situ temperature (8-10 �C), which may lead to low methane generation rates over a protracted period of time.
Keywords: Accelerated Biodegradability Test; closed landfill; leachate quality; methane potential.
A PRACTICAL APPROACH TO FUTURE MUNICIPAL SOLID WASTE MANAGEMENT IN DEVELOPING COUNTRIES—A CLOSER LOOK AT GEORGETOWN, GUYANA
Anita Z�vodsk�, Ph.D.
Assistant Dean for Academic Affairs, Assistant Professor of Environmental Sciences
School of Adult and Continuing Education, Barry University
8001 SW 36
th Street, Suite #1
Davie, FL 33328, USA
Tel: (305) 981-5224
The need for proper municipal solid waste management in developing countries is imperative because the effects of improper management practices on the environment and public health can be profound. Practical solutions to solid waste management problems today show that the technical answer is not always the sole answer. In many situations this is due partly to inadequate technical knowledge and partly to socioeconomic reasons, yet in spite of this, decisions still have to be made. Lack of information, be it scientific or social, is a common phenomenon in many developing countries where insufficient funding only exacerbates the problem. The aim of this study was to take all of this into consideration and to develop a methodology that would be specific in its recommendations to Guyana, but would be generic enough to be modified and applied to any other developing countries with similar characteristics. The final product was a quick, practical, cost-effective, and environmentally-sound ten-point checklist that could be utilised by solid waste planners in developing countries.
Keywords: municipal, solid waste, management, developing countries, methodology
UTILISATION OF INDUSTRIAL WASTE FLYASH AS AN ADULTERANT TO CLAY FOR THE MANUFACTURE OF MANGALORE ROOFING TILES
Dr. Susan Rego
Department of Built and Natural Environment
Caledonian College of Engineering Sultanate of Oman INDIA
Clay is the common name for a number of fine grained earthly materials that become plastic when wet. Clay is extensively used in ceramic industry in general and in the manufacturing of roofing tiles and bricks in particular in Dakshina Kannada district of coastal Karnataka.
In Dakshina Kannada clay tile manufacturing industries are the major constituent contributors for rural and urban housing across the coastal and hilly regions of India. However, these tile factories are now facing shortage of good quality clay. Nearly 50,000 acres of fertile top soil is removed till recent years for making bricks and tiles. This causes ecological unbalances specifically for an agricultural country like India .
On the other hand, technological advancement has brought in modern industries like thermal power plants and iron ore environment polluting and health hazardous waste products in huge quantity. The thermal power plants have problems in safe disposal of hazardous flyash. Fortunately, this flyash is found to possess potential characteristics which could be tapped for producing low cost building or clay roofing materials.
This paper presents the results of an experimental study made on utilization of flyash in appropriate proportions, with good quality clay for the manufacture of roofing tiles. It also presents the different types of fuels used, cost of production and the energy audit. From the results of this study, it is concluded that cost effective, ecofriendly and durable clay tiles could be produced with flyash as an additive in optimum proportion.
Keywords: Roofing tiles, clay, flyash, energy audit
EFFECTS OF PHOSPHATE CHEMICALS TREATMENTS ON AUTO BATTERY WASTE CONTAMINATED SOIL IN NIGERIA
M.B. Ogundiran* and O. Osibanjo
Department of Chemistry
University of Ibadan
Auto battery waste contaminated site poses potential threats to the environment and biological life through lead toxicity, thus making remediation imperative. The possibility of using phosphate chemicals to reclaim a grossly lead-contaminated site was explored. The study site was an abandoned lead-acid battery waste dumpsite in Nigeria. Phosphate chemicals were applied at 5 and 10% phosphorus levels to the contaminated soil collected from the site in incubation experiments. The air-dried sub-samples of the incubated soils were analyzed for pH, P, bioavailable Pb and TCLP- extractable Pb. Results showed that 99.5% of the applied phosphorus was removed by the end of the first week of incubation. Incubation time showed less effect on Pb immobilization. A 10% phosphorus application resulted in reductions of water soluble Pb between 77.8% and 86.4% thus eliminating to a reasonable extent, the hazard to living things and the environment. TCLP extractable Pb was reduced from 50.2 mg/L in untreated soil to below the acceptable value of 5.0 mg/L. An application of 10% CHP produced overall effectiveness in the reduction of bioavailable Pb, TCLP-extractable soil Pb. This treatment also had little effect on soil acidification and resulted in the least residual P. Results therefore indicated that phosphorus can be used as potential chemical remediation for cleanup of battery waste contaminated soils.
Keywords: Lead; contaminated soil; battery waste; remediation; phosphate chemicals; speciation
Issue 2, May 2009
SOLID WASTE MANAGEMENT IN ACCRA, GHANA—ANAEROBIC DIGESTION AS AN APPROPRIATE PRETREATMENT OPTION
PRIOR TO LANDFILLING
Department of Environmental Science, Faculty of Biosciences
Kwame Nkrumah University of Science & Technology, Kumasi, GHANA
Chair of Waste Management
Faculty of Environmental Sciences and Process Engineering Brandenburg
University of Technology, Siemens-Halske-Ring 8, 03046, Cottbus, GERMANY
This paper presents an overview of the problems of solid waste management in an urban centre-Accra, Ghana and certain important issues that must be considered in order to achieve success. Despite privatizing garbage collection, with the view of improving waste management services, there is still a severe waste management crisis throughout many parts of the metropolis. More waste is generated than collected by the waste authority and this has resulted in a deficit of solid waste left in the environment. Also, the waste collected and hauled to the dumpsite is not treated resulting in leachate pollution and greenhouse gas emissions. Diseases known to be environmentally related as a result of poor solid waste management are common. A detailed description of the situation in the metropolis is presented. In addition, biological pretreatment option is proposed as a sustainable approach towards the solution of the solid waste problem in the metropolis.
Keywords: Solid waste, Problems, Anaerobic Digestion, Accra, Pretreatment, sustainable
GEOTECHNICAL CHARACTERIZATION OF COAL ASHES FROM SARAWAK FOR BULK UTILIZATION
Prabir K. Kolay and Tony Kismoor
Senior Lecturer and Former Undergraduate Student
Faculty of Engineering, Department of Civil Engineering
Universiti Malaysia Sarawak
94300 Kota Samarahan, Sarawak, MALAYSIA
The utilization of the coal, for the generation of electrical energy, has been increased substantially from 4.2 to 13 million tones during the years 2000 to 2005 in Malaysia. As a result, it produces a large quantity of ashes as a by-product. The coal ash can be, and is being successfully used, for different applications e.g., a stabilizer of sub-grade and sub-bases in pavement construction; as a fill material; as a foundation material etc. But before utilization in different fields mainly as a bulk its physical and geotechnical properties (e.g., compaction, compressibility and shear strength) must be studied. The advantages of using coal ash as a bulk fill material include low cost, low unit weight, and good strength. However, not much attention has been paid locally to the characterization of the coal ashes and its utilization in Sarawak. Hence this paper describes some physical, chemical and geotechnical properties of coal ashes collected from Sejinkat Thermal Power Plant, Sarawak, Malaysia.
Keywords: Coal ash; Physical properties; Chemical properties; Compaction; Compressibility; Shear strength
THE SOLID WASTE ANALYSIS AND MINIMIZATION RESEARCH PROJECT—A COLLABORATIVE ECONOMIC STIMULUS AND ENVIRONMENTAL PROTECTION INITIATIVE IN NORTHWEST OHIO, USA
Matthew J. Franchetti
Dept. of Mechanical, Industrial and Manufacturing Engineering, University of Toledo 2801 West Bancroft Street
Toledo, Ohio 43606, USA
In 1996, an innovative partnership between the Lucas County Solid Waste Management District and The University of Toledo, College of Engineering was formed to help improve environmental and economic conditions in Lucas County, Ohio, USA by providing no cost solid waste assessments to Lucas County manufacturers and businesses. Since the inception of the project, over 70 waste assessments have been completed, over 109,000 tons of solid waste has been identified for reuse, reduction, or recycling and over $3.1 million have been identified as potential cost savings for Lucas County business. The purpose of this paper is to provide a complete overview and framework of this program so that other institutions may learn from it and adopt similar concepts to help reduce solid waste generation and improve economic conditions in their regions. A focus of this paper is a discussion of a case study that details the process and results of a typical solid waste assessment conducted through the project. Also included in this paper is a discussion of the project’s background, a comparison to similar project’s between colleges and government agencies, and results and benefits of the program, and an overview of the opportunities and barriers to this type of research. The project demonstrates that through a cooperative effort and a creative alliance, businesses, governments, universities, and industries can work together to improve environmental quality, reduce waste, and improve profitability. The project also educates college students though practical, real-world environmental work experience and trains them to become future environmental leaders.
Keywords: Waste assessments, recycling, economic analysis
PYROLYSIS OF SCRAP TIRE FOR PREPARATION
OF ACTIVATED CARBON
Monash University, Sunway Campus
46150 Petaling Jaya, Selangor Darul Ehsan, MALAYSIA
AC College of Technology
Anna University, Chennai, T.N., INDIA
The presented work is an attempt to produce activated carbon from the pyrolytic char of the scrap tire, using phosphoric acid as the activating agent. Towards this, as a first step, pyrolytic char was prepared from scrap tires covering a temperature range of 400 to 800�C. The yield of the char was found to vary in a narrow range of 33 to 35% for the temperatures exceeding 450C. The resultant pyrolytic char was impregnated with phosphoric acid and activated at 500�C, for duration of activation ranging from 45 to 150 minutes, for impregnation ratios of 1 and 1.5. An impregnation ratio of 1 was found to yield 42%, with a methylene blue number of 184mg/g, while an impregnation ratio of 1.5, yielded 52% with methylene blue number of 139mg/g. The methylene blue number was found to increase with increase in activation time or with decrease in the yield of the activated carbon. The BET surface area was found to increase with increase in the methylene blue number from 302m2/g to 545m2/g. While all the earlier work using chemical activation reports activation temperature around 800�C, in an inert atmosphere, the present process demands only 500�C, in a self generated atmosphere, to produce activated carbon of comparable quality.
Keywords: Pyrolysis, Phosphoric acid Activation, Char, Methylene blue
PREDICTION OF LEACHATE FLOW-RATE IN A MSW LANDFILL SITE USING NEURAL NETWORKS METHOD
DOE Samuel Massie Chair Professor
Graduate Research Assistant
Civil and Environmental Engineering Department
North Carolina Agricultural and Technical State University
Greensboro, NC 27411, USA
Landfill leachate may percolate soils and contaminate groundwater and thus becomes harmful to human health and environment. Many research projects have been conducted to control the leachate generation and simulate the leachate flow, such as the water balance method (WBM) and the Flow Investigation of Landfill Leachate (FILL) model. Other than conventional estimation approaches, the quantity of leachate can also be obtained by forecasting. In this paper, an artificial neural networks (ANNs) model was presented for the prediction of the leachate flow rate in a municipal solid waste (MSW) landfill site.
The model was developed by a number of design steps, which include data collection, model training, model testing and model validating. As a result of model development, this model was designed with an appropriate architecture for good accuracy and fast convergence. The necessary landfill design data needed to calculate the quantity of leachate were obtained from the US EPA’s Hydrologic Evaluation of Landfill Performance (HELP) model, which is a versatile and accepted landfill design and modeling program. Four soil characteristic parameters, which are porosity, field capacity, wilting point and saturated hydraulic conductivity, in addition to the thickness of refuse layer were varied to generate the corresponding leachate flow rates. Using these pairs of data, the ANNs model was “trained” to produce a desired input and output relationship by a back-propagation (BP) algorithm. With the above configurations, the proposed ANNs model was illustrated to be efficient and accurate in the prediction of leachate flow rates with various data sets. Sensitivity analysis among the five variable parameters was also discussed in this paper.
Keywords: Neural network; Model prediction; Leachate generation; Landfill
LEACHING STUDIES AND METAL ANALYSIS OF FLY ASH FROM THERMAL POWER PLANT OF INDIA
Research Scholar, Department of Water Resource Development and Management
Associate Professor, Department of Water Resource Development and Management
Phone: +91-1332-285393 ; Fax: +91-1332-271073; Email: firstname.lastname@example.org
Emeritus Fellow, Department of Water Resource Development and Management
Indian Institute of Technology Roorkee
Major by-product of coal fired power plants is fly ash. Apart from dry disposal, most of the power plants in India still follow wet disposal (ash pond) method. The successful management of waste arising from the combustion of low rank coal for electricity generation presents significant engineering and environmental challenge. X-ray diffractometer studies were carried out on fly ash for the identification of minerals whereas morphology was examined with the help of scanning electron microscope. It was found that majority of fly ash particles are spherical in shape. Elemental composition was determined with the help of FE-SEM EDAX analysis. Leaching behavior of fly ash was investigated with the help of open column percolation test. Leachates were analyzed for pH, conductivity, TDS, salinity. It has been found that the conductivity, TDS and salinity decreases with time. Iron and Manganese were analyzed with help of spectrophotometer DR-2800. Maximum observed values for Iron and Manganese were 0.31mg/lit and 0.9 mg/lit respectively. Further it is found that concentration of iron and manganese also decreases with time.
Keywords: Fly ash disposal; leaching; XRD; SEM graph; leachate analysis; metals
Issue 1, February 2009
COMPATIBILITY OF CEREAL STRAW WITH HYDRATION OF CEMENT
Department Civil and Environmental Engineering, Michigan State University
Room 3546, Engineering Building, East Lansing, MI 48824-1226, USA
Email: email@example.com; Tel: (517) 355 2216; Fax: (517) 432 1827
Department of Construction, Faculty of Technical Education
Gazi University, 06500, Ankara, Turkey
1926 Tunrner St., Lansing, MI 48906, USA
Department Civil and Environmental Engineering, Michigan State University
Room 3546, Engineering Building, East Lansing, MI 48824-1226, USA
Cereal straw is an abundantly available agricultural by-product with attractive mechanical performance and cost position for reinforcement of cement-based products. The composition of straw, however, is distinguished from that of wood by the presence of relatively large quantity extractives with potentially strong inhibitory effects on strength development of cement. Thin-sheet fiber cement products offer attractive technical, economic and aesthetic qualities for use in diverse building construction applications, including siding and tile backerboard. Commercially successful thin-sheet fiber cement products generally utilize chemically processed wood pulp or mechanically milled wood as reinforcement for achieving enhanced levels of flexural strength, toughness and workability. Cereal straw offers a slender geometry which favors their mechanical processing as replacement for milled wood in thin-sheet cement products. As a renewable resource and as a generally low-valued agricultural residue, straw offers economic and environmental advantages for replacement of wood in thin-sheet cement products. The differences in composition of wood and straw should be considered in devising pre-treatment techniques for use of straw in conjunction with cement. Such pre-treatments should address the potential for inhibitory effects of some straw constituents on strength development of cement.
Keywords: Straw; Treatment; Cement; Strength development; Reinforcement
COMPATIBILITY AND ATTENUATIVE PROPERTIES OF BLAST FURNACE SLAG TREATED LATERITE
Kolawole J. Osinubi
Professor, Dept. of Civil Engineering, Ahmadu Bello University
Zaria 810001 NIGERIA
Tel: +2348037037241, Email: firstname.lastname@example.org
Adrian O. Eberemu
Lecturer, Dept. of Civil Engineering, UNIAGRIC Makurdi
Benue State, NIGERIA
Major concerns exist regarding potential pollution problems related to contamination by toxic liquids emanating from waste landfills. Increasing environmental awareness is making it necessary to assess the effects of waste leachates in proposed clayey liners for waste landfills. Results of a study on the feasibility of using laterite treated with ground blast furnace slag (BFS) as a construction material for waste containment liners and impermeable covers are presented. Liners can be constructed using laterite treated with ground BFS to meet the regulatory permeability value of < 1x 10-9 m/s. The effects of permeation with municipal solid waste (MSW) leachate on compacted soil treated with up to 15% ground BFS at the energy of the British Standard heavy (BSH) compaction using different molding water contents for a period of one month are reported. Batch equilibrium studies were conducted for a duration of 48 hours using 0, 5, 10, 15 and 100% ground BFS treated soil, respectively. The MSW leachate had no detrimental effect on the liner permeability. Adsorption isotherms were obtained for the cations of calcium, iron and chromium that were selected to represent the dominant and critical contaminants in the leachate and these showed strong attenuative properties. 5% BFS treatment gave the optimum mix performance.
Keywords: Adsorption Isotherm, Attenuation, Batch Equilibrium, Compatibility, Hydraulic Conductivity, Laterite, Municipal Waste Leachate
APPLICATION OF IONIZING RADIATION FOR SLUDGE DISINFECTION AND ITS USE FOR IRRIGATION AND FERTILIZATION
Department of Biomedical Engineering, Ben Gurion University
POB 653 Beer Sheva, ISRAEL
Department of Biothechnology, Ben Gurion University
POB 653 Beer Sheva 84105, ISRAEL
The sludge produced in the central, most populated area in Israel, is now dumped into the sea. Ionizing radiation was used to investigate the possibility of developing an industrial method for disinfection of the sludge, preparing it for use in farm land for irrigation and fertilization. A simple and inexpensive method for disinfection and preparing it for agricultural use is proposed. Sludge samples were irradiated with photons and electrons, it was found that relatively low radiation dose is enough to bring it to level A which is acceptable for the proposed use. Any dose of gamma radiation from a Co 60 source, from 0.2 Mrad and up, killed all coliforms in the sludge. Similar results were obtained for 3 MeV electrons. The irradiation stopped all biological activity in the sludge, therefore causing the solid part to separate from the water and sink. This stopped the gas (odor) emission from the sludge. The radiation did not have any effect on the heavy metals concentration in the sludge, but had some effect on the concentration of some of the light elements (some of it remained in the solid). The water, containing important minerals, was then tested for field irrigation. The product was tested for irrigation using droppers and found to be suitable.
Keywords: Sludge, Irradiation, Coliform, Disinfection, Gases emission, Droppers
SORPTION POTENTIAL OF THE BIOMASSES OF PEANUT HULL AND FLY ASH FOR DECOLOURIZATION OF METHYLENE BLUE AQUEOUS SOLUTION
Chemistry Department, Aswan Faculty of Science
Aswan 81528, EGYPT
The sorption potential of either peanut hull or fly ash to decolourize the aqueous solution of methylene blue (MB) was investigated at room temperature. Many operating variables were studied in a batch technique. Of these, solution pH, dosage of the used sorbent biomass, initial dye concentration and the applied contact time.
The resulting data was fitted and was more suitable by Langmuir isotherm model than the Freundlich one confirming the formation of monolayer from the sorbed dye on the sorbent surface. All parameters of Freundlich and Langmuir were calculated from the experimental results. The transient behaviour of the batch sorption process at different initial MB concentration was analyzed utilizing Lagergren pseudo first-order kinetic model and Ho and McKay pseudo second-order model.
Keywords: Sorption, Peanut Hull, Fly Ash, Methylene Blue, Isotherm Models, Kinetic Models, Chemisorption
AN IMPROVED NUMERICAL DESIGN METHOD FOR THE REMEDIATION OF CONTAMINATED SITES BASED ON SENSITIVE TRACER TESTS
Kazuei Ishii and Toru Furuichi
Laboratory of Sound Material-Cycle Systems Planning
Graduate School of Engineering, Hokkaido University
N13, W8, Kita-ku, Sapporo, 060-8628, JAPAN
Tel: +81-011-706-7284; Fax: +81-011-706-7287
We proposed an improved numerical design method for the remediation of contaminated sites based on a sensitive tracer test using rare earth metals such as holmium. The numerical design method was then applied to a real contaminated site, where immediate countermeasures were required because of detection of high arsenic concentration in a spring near a sea line outside the site. First, the sensitive tracer test using insium, europium and holmium under natural gradient condition revealed the groundwater flow path from the three suspected source points to the sea line, and analysis of the breakthrough curve for each tracer compounds determined the parameters, such as the hydraulic conductivity and dispersivity. A site-specific model representing the distribution of acrcenic concentration in groundwater identified the source points, responsible for the contamination of the spring, and revealed that contaminated groundwater might flow out of the site boundary. A vertical wall was designed to prevent contaminants spreading from the site, and the change in the arsenic concentration after the construction of the vertical wall was predicted. The prediction had similar tendency to the actual decrease in arsenic concentration over a two-year monitoring phase. Consequently, our numerical design based on the sensitive tracer test predicted that the contamination level in the groundwater around the spring would continuously decrease toward remediation.
Keywords: Groundwater contamination, sludge contaminated by arsenic, numerical design method, sensitive tracer test
DRIVING COMMERCIAL AND INDUSTRIAL WASTE REDUCTION IN QUEENSLAND, AUSTRALIA — THE POTENTIAL APPLICATION OF A UK WASTE MINIMISATION CLUB MODEL
Griffith University, Centre for Environmental Systems Research
Brisbane QLD 4115, AUSTRALIA
Paul Phillips and Thomas Coskeran
University of Northampton, SITA Centre, School of Applied Sciences
Northampton NN2 7AL, UK
Queensland (QLD) is the second largest state in Australia with an area of 1,734,157 km2 and a population of some 4,132,000 (less than 20% of Australia’s total population). The majority of QLD’s population is located in the South East (SEQ) region around Brisbane and the Gold Coast with further population densities along the coast. SEQ is growing rapidly, with SEQ receiving over 1,000 new immigrants (both interstate and international) to the region every week, which is stimulating the housing, retail and commercial and industrial sectors. This growth in population and development is leading to an increase in waste arisings across all sectors. During 2005, QLD generated approximately 444,000 tonnes of commercial and industrial waste, with only 23,000 tonnes being recycled, equating to only 5% of the amount generated. By comparison, during 2005 the UK generated 83 million tonnes of commercial and industrial wastes of which approximately 45% was recycled. QLD has a suite of environmental and specific waste management legislation relating to the management of all waste streams which adopts the waste management hierarchy. The regulatory framework of any State or Country can if well designed drive sustainable waste management practices within the commercial and industrial sectors.
Waste minimisation clubs (WMCs) were initiated in the 1990s in the UK in order to assist commercial organisations minimise their waste streams and identify re-use and recycling opportunities, including e.g. waste exchanges. WMCs have been an important demonstration opportunity for companies to grasp the benefits of the sustainable management of commercial and industrial wastes as well as the possible adoption of cleaner production through new technology.
This paper reviews the trend of WMCs in the UK and discusses their potential application to QLD. It explores the drivers and barriers for such implementations within QLD, including the absence of a landfill levy and legislative barriers. The paper also discusses Australian government initiatives for improving resource efficiency within industry, and the benefits and limitations of these schemes. Case studies from the UK are then provided to ascertain the opportunities for possible WMC development in QLD.
Keywords: Resource, Waste Minimisation Clubs, Landfill Levy, Queensland, UK