Volume 24, 1998
Issue 3/4,November 1998
A Methodology To Estimate The Carbob Off-Set Potential Of Composting Bio-Degradable
Municipal Solid Waste(BMSW)
J.P.Hettiaratchi, R.Pradhan
Associate Professor and Research Associate
Engineering for the Environment Program
Dept.Of Civil Engg
University of Calgary
Calgary,Alberta,Canda T2N 1N4
K.Gunsch, J.L. Leskiw
Project Manager and Consultant
TransAlta Corporation
Calgary,Alberta,Canda T2P 2M1
ABSTRACT
Methane(CH4) emissions from landfills accepting biodegradable municipal solid waste(BMSW) is a growing global concern as Ch4 isa potent greenhouse gas with 21 times more global warming potential than carbon dioxide(CO2) over a 00 year time horizon.Diverting BMSW from landfills to a composting facility could produce substantial short-term global warming benefits.Although composting does not produce CH4 the process of composting and the application of finsihed compost on land produce large quantites of CO2.Therefore to assess the global warming benefits of composting,methods are required to estimate the net greenhouse gas(GHG0 emission reduciton achieved by implementing composting instead of landfilling.The carbon off-set potential of various waste management alternatives is presented in this paper.The model incorporates a Life Cycle Approach although ll activites related to the competing waste management alternatives are considered,only the ones emitting significant GHGs are included in the model.A model application is presented.The COP model estiamtes a net benefit of about 1.2 million tonnes of carbon equivalents(TOCEs) or about 60% net TOCE reductions by composting 215,000 tonnes of MSw and 22,500 dry tonnes of digested bio-soilds annually over 30 years,instead of landiflling MSW and direct application of bio-solids on land.
Key Words: Solid waste,Bio-solids,Greenhouse gas,Carbon-offset potential,Composting,Landfilling.
Lightweight Masonry Blocks And Bricks From Waste Solids
Silvio Delvasto,Ruby Mejia de Gutierrez
Titular Professors
Universidad del Valle
Apartado aereo 25360 ,Cali ,Colombia
Natalia Parra,Gustavo Insuasty
Civil Engineers
Universidad del Valle
Apartado aereo 25360 ,Cali ,Colombia
ABSTRACT
Lightweight Masonry blocks were produced from industrail residues of polystyrene and bricks from aluminium profile chips and a kind of silica farnia which i s fine leftover of the production of aggregate for concrete(FAC).
The concretes designs were mainly related to comply with the ASTM requirements about compressive strength,density and water absorption.Normal curing was used for a polystyrene added concrete(PAC) and high pressure steam curing for a cellular concrete(ACC) prepared by incorporation of wasted aluminium chips and FAC.
The best result gotten was 5.0 MPa(709 psi) reported by the PAC when the apparent density was 1450 kg/m3
The ACC specimens showed a maximum stength of 2.6 MPa(362psi).The water absorption ranged from 1.9 to 30.6 %.The results of this study indicated that tried industrial waste remainings could be suitable to produce lightweight masonry blocks for non-load bearing applicatins with weather protective coatings.
Key Words: Lightweigh concrete,masonary blocks,cellular concrete,aluminium,polystyrene,silica farina.
An Expert System For the Conceptual Desing Of Sanitary landfill Operation
Dr.Hassan Basri
Dept.Of Civil Engg
Universiti Kebangsaan ,Malaysia
43600 UKM BANGI, Malaysia
ABSTRACT
The application of expert systems technology in the sanitary landfilling domain is particularly appropriate in order to preserve and disseminate valubale experience efficiently at reasonable costs.Despite the simplicity in the design and operational concepts of landfilling works there is a conspicuous scarcity in availabel expertise for its implementation in a developing country such as Malaysia.Research has been carried out to develop an expert system prototype,the Landfill Operation Advisor(LOA) for the conceptual design of sanitary landfill operation.An expert system shell ,Kappa-PC was selected as the developemtn tool for the LOA prototype because of its object-oriented approach which combines the two main knowledge representation techniques for expert systems i.e production rules and objects.The LOA modules cover the taks of operation plan ,filling plan,mechanisation and manpower requirements health and nuisance considerations,site preparation,operational facilities adn environmental monitoring.The knowledge acquisition process for the LOA adopted a methodology where exertise is acquired from a variety of sources using suitable techniques such as text analysis,unstructured interviews and observations of landfilling works.The overall performance of the LOA in dealing with the intended scope of work was evaluated to be satisfactory.
Key Words: Expert System,Sanitary alndifll,Knowledge absed system,Solid Waste Management,Knowledge acquisition ,Object oriented programming.
Study on the Efficacy And Mechanism Of Excess Sludge By Aerobic Digestion Treatment
Jun Yin ,Chunsheng Shou
Jilin Architectural adn Engineering Institute
Changchun
P.R. China-130021
Hai Bu
Changchun City Municipal Engineering Design
Research Institute
P.R.Chian 130041
ABSTRACT
In this paper the efficiency and mechansim of aerobic digestion of excess sludge of different concentrations at temperature 300 were studied and discussed.The sludge was originated from a composite wste treatment station of a motor industry.Dynamic analysis was also presented.The results indicated that volatile suspended soilds(VSS) removal of 52.65~64.71% could be obtained under the condition of the initial sludge mixed liquor suspended solids(MLSS) concentration at a range of 10197~20229mg/L.Both VSS removal amount and degradation rate constant (Kd) increased with increasing sludge concentration.On the contrary VSS removalrate decreased with increasing the sludge concentration.It has given considerably satisfactory explaination on the result of the test through the determination of parameters of TTC-Dehydrogenase activity(TTC-DHA) etc of the sludge.
Key Words: Aerobic digestion,excess activated sludge,oxygen uptake rate,TTC-Dehydorgenase activity,VSS removal amount.
The Viablity Of Recycling Plastic By Tertiary Processes
T.Randall Curlee,Sujit Das
Energy Division
Oak Ridge National Laboratory
Oak Ridge,TN 37831-6205
ABSTRACT
This paper examines the viablity of tertiary recycling (depolymerizatin of a clean stream) as an alternative to secondary recycling(i.e mechanical recycling), quaternary recycling(i.e incineration wiht heat recovery) and disposal by landifling.A life cycle approach which addresses both financial and environmental costs and benefits is adopted to compare the alternatives.The discussion focusses not only on the full costs and benefits of the competing approaches but alos the perspectives of the parties that incur these costs and benefits.
The limited information currently available suggests that depolymerization is not a particulary attractive approach from a finiancial perspective.Current secondary recycling technologies that utilize clean PET and HDPE appear to be superior in this regard.In addition,depolymerization processes do not appear to hold significant environmental advantages over currently available secondary processes.Although data on the environmental implictions of deploymerization and secondary processes targeted at clean waste(i.e depolymerizations closes competitor) are limited there is no strong evidence that depolymerization results inlower overall emissions or damages.This position is supported by the fact that both secondary recycling and depolymerization displace virgin resins.From an energy balance perspective,tertiary recycling appears to hold no particular advantage,Finally tertiary recycling currently holds no advantage over secondary recycling in terms of conservation of materials-once again because tertiary and secondary recycling of lcean ,single resin waste streams both displace virgin polymers.And there is no evidence to suggest that additional secondary recycling of clean plastioc waste is limited by potential market size.
Key Words: Tertiary,Plastics,Recycling,Life Cycle,Costs,Energy.
Infiltration Rates Through Landfill Cover Systems
Guangbin He, Kau-Fui V.Wong
Dept.Of Mechanical Engg.
College of Engineering
University of Miami
Coral Gables.FL 33124
Helena Solo Gabriels
Dept.Of Civil Architectural and Environmental Engg.
College of Engineering
University of Miami
Coral Gables.FL 33124
ABSTRACT
Landfill infiltration rates were evaluated for three fully closed landfills using the Hydrologic Evaluation of Landifll Performance(HELP) Model.The data utilized for this analysis were scarce due to the limited number of landfills which are fully closed with well designed leachated collection systems and with synthetic top liners.The analysis included herin represents a unique evaluation of infiltration rates utilizing field scale landfill data.Results indicated that the recommended ranges of parameters suggested through HELP documentation were adequated for simulating landfill performance.For the three landfills analyzed the average yarly infiltration represented from 4% to 17% of the rainfall volume and the results indicated that the infiltration rates through the side slopes without synthetic linere were greater than that through the top caps with synthetic liners.Regression realtionships between infiltration and rainfall were developed for different landfill designs.Results are of practical significance since they can be used by landfill operators to analyze the cost effectivness of installing synthetic liners into the cover systmes of sanitray landfills.
Key Words: Landfill,infiltration rate,HELP model,leachate volume,synthetic liner.
Innovative And Traditional Landfills:Laboratory Scale Plants Comparision
M.R.Boni,G.Lombardi,E.Rolle
University of Rome “La Sapienza”
Faculty of Engineering
Via Eudossiana 18,00184 Rome
ABSTRACT
Municipal solid waste(MSW) aerobic landfilling is suitable way to minimize environmental impact.Recent studies have in fact shwon there are several advantages to be obtained by using this innovative technology as:
- improvements of leachate characteristics
- lower production of landfill gas
- briefer site recovery times
During landifill operation it is possible to establish a first phase under aerobic conditions(pretreatment) followed by a sencond phase under anoxic/anaerobic conditions(traditional landfilling) .The results of a laboratory scale research aimed at quantifying the above mentioned advantages are illustrated in this paper.
The first results showed that during the aerobic phase(plant A) the variation in specific volume of the waste pile was about twice that of the aerobic phase.Comparision between the leachate characteristics form the reactors A and B showed that the COD value in plant A was ten times lower than that recorded in plant B.
Key Words: Innovative landfill,Aerobic pretreatment,improvement of landfill operation,Municipal solid waste,
Organic fraction stabilization,Leachate.
Modelling Sanitary Landraise Capacity As a Function Of Various Parameters
V.Aivaliotis Lecturer
D.Pnagiotakopoulos,Professor
Dept.Of Civil Engg
Democritu University of Thrace
67100 Xanthi Thrace Greece
ABSTRACT
In the process of palnning and designing a sanitary landfill(LF) or a landraise(LR) over a given base area,specific choices have tobe made regarding the size of several geometric adn operational desing parameters(d.p) such as :side slopes,lift height,bench width between lifts,length of daily workign front,cell ocover thickness (top,side,front) and final cover thickness.These choices affect the capacity V(space available for wastes) the operation physical life adn the construction and operation costs of teh LF/LR.To date no functional relationships between V and these d.p have been reported in the literature to a satisfactory degree for the designer.
In this work such relationships are developed for a LR of specific morphology,relating capacity V with:
1. the LR base area size
2. each of the above eight d.p
The capacity is a multiplicative function of the base size.Moreover it can be expressed as a linear function of the form V= ¤i + (Òi* xi) for every d.p.i where xi is the value of d.p.i and ¤i and Òi are constants generated through simulation and depending on base size and shape.
The implications to LF/LR planning and design are significant,since the desinger can easily assess the impact of his choices for d.p sizes on capacity and make the necessary trade-off analyses.
Key Words: Landfill Capacity,Landfill Design Parameters,Landfill Planning,Landfill Functions.
Land Use And Development Experiences with Closed Sanitary Landfill Sites
Berrin Tansel
Associate Professor
Civil and Environmental Department
Florida International University
Miami Florida USA 33199
ABSTRACT
Closed sanitray landfill sites have been developed for use as open areas for recreation and industrial and commercail areas with structures.Both conventioanl and unconventional land development practices for closed sanitary landfills require careful planning before the landifll development begins.The major areas of concerns for developing closed sanitary landfills sites are settlement of the landfill surfaces after closrue.low bearing capacity to support structures,formation and migration of landfill gases adn corrosive environment due to the presence of acids in subsurface forming during decompositions of solid waste.Although structural developments on landfills are not recommended,in densely populated areas where property is scare and land values are high,land uses incorporating structures have been practiced.Successful developments with structural facilities acquire specail design considerations such as leaving undisturbed areas for structural pads during solid wste deposition and using acid resistant concrete.This paper provides an overview of the experiences with developemtn of landfills for both conventioanl and unconventional land use purposes.
Key Words: Landfills,closed landfills,bearing capacity,landuse,solid waste disposal.
Design And Construction of Full-Scale Demonstration Lagoon Using Coal Combustion By-Products
Tarunjit S.Butalia Ph.D,P.E
Dept.Of Civil & Environmental Engineering & Geodectic Science
The Ohio State University
470 Hitchcock hall,2070 Neil Avenue
Columbus Ohio 43210 USA
Shan Mafi
American Electric Power Sevice Corporation
Columbus,Ohio USA
William E.Wolfe Ph.D,P.E
The Ohio State University
Columbus Ohio 43210 USA
ABSTRACT
The desing and construction ofa full scale demonstration lagoon/pond to study the suitablity of coal combustion by products as low permeability liners,in place of commonly used clay and synthetic liners is presented.lab testing of stabilized Flue Gas Desulfurization(FGD) samples has shown that the permeability values for compacted FGD material can be lower than the 1* 10-7 cm/sec (3.28 * 10-9feet/sec) value required by US Environmental Protection Agency (EPA) for constructing liners for wste containment facilities.However since permeability is likely to be a fucntion of the construction process,field validation of the properties obtained in th lab is an improtant part of the documentation process.The design adn construction of such a full-scale testing faciltiy to evaluate the performance of a field compacted FGD liner is presented.
Key Words: Coal Combustion By-Products,FGD,Impervious Liner,Waste Containment Facilities
Use Of Automotive Paint Sludge As filler in Asphaltic Mixtures
Gloria Maria Martinez Gonzalez , Pedro Alberto Quintana Hernandez
Angel Castro Aguero,Guillermo Gonzalez Alatorre
Instituto Tecnologico de Celaya
Dpto.de Ing Quimica Ave Tecnologico y Garcai Cubas
38010 celaya Guanajuato
Mexico
Agustin Jaime Castro Montoya
Instituto Tecnologico de Orizaba
Dpto.de estudios de Posgrado Ave Tecnologico No 852
94320 Orizaba Veracruz
Mexico
ABSTRACT
In this study the feasibility of using automotive paint sludges as fillers in asphalatic mixtures was investigated.Three different amounts of sludge in an asphaltic mixture were tested.Hazardous elements present in the automotive paint sludges were eliminated are fixed.The Volatile Organic Compounds were eliminated from the sludge by a drying process and heavy metals such as chromium were fixed using an asphaltic resin.The dried sludge was milled,screened adn incorporated as filler in asphaltic mixture.The results showed that the incorporation of sludge into the pavement mixture improved its stability,adn in all cases satisfied the Official Ecological Norms.
Key Words: Asphaltic mixtures,automotive paint,fillers,metal fixation,pollution,sludges.
Issue 2, May 1998
Mathematical Model to Estiamte Emissions of Volatile Organic Compounds
from Municipal Landfills
Eyal Rotenberg and Yaacov Mamane
Environmental and Water Resources Engineering
Technion Haifa 32000
Israel
ABSTRACT
A mathematical model describing the emissions of volatile organci compounds(VOCs) from municipal landfills is described.The model assumes that the gas movement from a landfill
to the atmosphere is described by molecular diffusion.The gases are emitted upward and
are removed at once from the top layer.The model includes a generation term:the production of VOCs caused by degradation processes.The VOCs concentrations at the interface of waste and soil layers are given by Henry’s law, adn the movement of pollutants is described using time dependant differential diffusion equation that is solved analytically.Two cases were considered: uncovered waste layer site, and waste that is covered with a solid layer.The input parameters for the model equations were taken from the published literature.
The main results obtained from this model are as follows:
a. The emission rates are proportional to gas production in the waste layer
b. For a waste layer covered with soild the emission rates of VOCs are remarkably slower
for the first years of operation.
Key Words: Landfill; Municipal Waste;VOCs; Emission rates; Mathematical Model.
Solid Waste Gasification: Energy Recovery From Polyethylene Biomass Mixtures
Paola Cipriani,Paolo De Filippis,Fausto Pochetti
Department of Chemical Engineering
University of Rome “La Sapienza”
Rome
Italy
ABSTRACT
A fludized bed reactor was used to study the gas composition of solid waste steam
gasification.Two different mixtures were prepared to investigate the effect of polyethylene on the biomass gasification and on the produced gas composition.Four different gasification temperatures ranging from 750 to 920 0C were used in order to obtain a gas composition rich in hydrogen.
Key Words: Gasification, Energy Recovery, Polyethylen biomass mixtures,Shift Reaction
Comparative Analysis of Fluorescent Lamp Recycling and Diposal Options
Berrin Tansel
Associate Professor
Civil and Environmental Engineering Department
Florida International University
Miami Florida
Brenda Reyes-Osorno
Project Engineer
Dade International, Inc
Ibrahim N.Tansel
Associate Professor
Mechanical Engineering Department
Florida International University
ABSTRACT
Over 600 million fluorescent lamps are disposed each year in the US.A large fraction of the fluorescent lamps are used in industrial areas which are routinely replaced resulting in generation of large quantities of used lamps.Approximately 82% of the lamps disposed are landfilled,16% are incinerated and only 2% are recycled. Disposal of large quantities of fluorescent lamps in landfills is a concern due to the potential risks to human health and the environmenta caused by mercury leaching. This paper investigates economic feasibility of recycling methods for fluorescent lamps in comparison to landfill disposal.Overall waste management costs for used fluorescent lamps depend on factors such as quantity of used lamps ,proximity of disposal site and recycling facility and state and local taxes.In this study three waste management scenarios were evaluated from an economic perspective.The waste management options evaluated included:
1. disposing of fluroscent lamps in an hazardous waste landfill
2. disposing a portion of the lamps as industrial waste based on chemical testing and the
remainder in an hazardous waste landfill
3. recycling
Key Words: Fluorescent lamps, fluorescent lamp disposal,fluorescent lamp recycling,mercury recovery ,energy efficiency,lighting.
Settlement in Municipal Solid Waste Landfills I. Field Scale Experiments
Mutasem El-Fadel
Faculty of Engineering and Architecture
American University of Beruit,Lebanon
850 Third Avenue
New York Ny 10022
Hana Al-Rashed
Kuwaiti Engineering Group
Safat,Kuwait
ABSTRACT
The biodegradation of organic matter in MSW landfills increases the void ratio and weakens the structural strength of the refuse within a landfill leading to a substantial loss of volume and settlement.Develpmen of completed landfill sites which is highly desirable particularly in land-limited locations,is invariably hindered by these settlements.Estimating long term landifll settlements becomes an integral part towards final site closure and ultimate usage.The rate and magnitude of these settlements depeend primarily on refuse composition and operational-management practices which affect bio-degradation adn stabliization processes within landfills.
Field scale experiments were conducted to measure refuse settlements rates under different operational management practices including leachate recirculation,addition of water ,buffer and microbbial seed.THe effect of these practices on settlemetn rates and magnitudes is evlauated.The field test data are used to calibrate mathematical models that are traditionally used in soil consolidation.The models can be applied to simulate landfill settlement rates and corelate these rates to refuse biodegradation and stabilization processes within landiflls.The present research work is presented in series of two papers:
I. field scale experiments
II. mathematical modeling of settlemetn behaviour.
Key Words:Landfill,solid waste,settlement, biodegradation,mathematical modelling.
Settlement in Municipal Solid Waste Landfills II Mathematical Modeling
Mutasem El-Fadel
Faculty of Engineering and Architecture
American University of Beruit,Lebanon
850 Third Avenue
New York,NY 10022
Hana Al-Rashed
Kuwaiti Engineering Group
Safat Kuwait
ABSTRACT
The biodegradation of organic matter in MSW landfills increases the void ratio and weakens the structural strength of the refuse within a landfill leading to a substantial loss of volume and settlement.Develpmen of completed landfill sites which is highly desirable particularly in land-limited locations,is invariably hindered by these settlements.Estimating long term landifll settlements becomes an integral part towards final site closure and ultimate usage.The rate and magnitude of these settlements depeend primarily on refuse composition and operational-management practices which affect bio-degradation adn stabliization processes within landfills.
Field scale experiments were conducted to measure refuse settlements rates under different operational management practices including leachate recirculation,addition of water ,buffer and microbbial seed.THe effect of these practices on settlemetn rates and magnitudes is evlauated.The field test data are used to calibrate mathematical models that are traditionally used in soil consolidation.The models can be applied to simulate landfill settlement rates and corelate these rates to refuse biodegradation and stabilization processes within landiflls.The present research work is presented in series of two papers:
I. field scale experiments
II. mathematical modeling of settlemetn behaviour.
Key Words:Landfill,solid waste,settlement, biodegradation,mathematical modelling.
Use of Recycled Plastic Resins in Infrastructure Construction Materials
Prof.Dimitrios G. Goulias
Program Coordinator
Highway Engineering
Prof.Ilan Juran
Head Civil & Environmental Engineering
Polytechnic University
Brooklyn, nY 11201
ABSTRACT
City and State agencies are faced with the problem of disposing of a signficant volume of waste materials.While in the past incineration and burial have beeen the common methods of disposing of plastics,rubber,glass,ash and other products of a municipal solid waste(MSW),the environmental concerns,the increasing cost of landfills, and the recongnition of the salvage avalue of these products promotes the drastic reduction of landfilled material.For example the City of New York is planning to drastically increase the recycling of waste from 12% to 42% of MSW by the year 2000.
The infrastructure construction materials provide a significant market potential for recycling plastic resins.The infrastructure industry has been investigating the use of recycled plastic resins for improving material quality and durability for a long time.Today, there are several examples of construction materials and products containing recycled plastic resins,such as pavement joint sealnats,polymers modified asphalt and concrete,roofing materials, geotextiles,traffice cones and others.This paper describes the research to practice cases known today in the use of recycledresins in infrastructure construction materials.Recycled plastic resins are routinely used for producing polymer modified highway and building materials and traffic control devices.On the other hand in an attempt to address:
1.societys need for safe and economical disposal of discarded plastic resins.
2. the infrastructure communitys need for better,long lasting and cost effective materials ,significant research and effort is being directed today in identfying new uses adn applications for these resins.
Several of these developments and uses are presented in this paper along with the identification of application requirements and needs.
Key Words: Plastics,recycling,highway materials,asphalt,concrete,economics waste stream.
Performance of GGBS Cements
R.Gutierrez, S.Delvasto
Engineering Materials Department
Universidad del Valle
Colombia
R.Talero
Construction Science Institue
Madrid
Spain
ABSTRACT
The incopration of materials such as blast-furnace slags and pozzolans in concrete which were initially used to preserve the environment and conserve energy,has been shown to improve the durability of the concrete.This paper presents some epxerimental results for blended cements containing blast furnace slag,a by product of the manufacture of iron.Three blended cements were prepared containing 60,70 and 80 % of ground granualted blast furnace slag(GGBS).Compressive strength,water absorption ,chloride permeability and reinforcement – corrossion were measures.Other properties such as chemical composition and morphology of the slag were also determined .
The results show that the addition of slag increases the compressive strength and reduces the diffusion rate of chloride irons.This is attributed to the densifying action and lower connected porosity of the concrete.The GGBS mortar had a higher chloride binding capacity than the ordinary Portland cement(OPC) mortar control.
A mortar containing 60% of slag was found to develop 17% more comressive strength than the OPC control mortar at 28 days and the coefficients of chloride diffusion was reduced to around 73% of the OPC control value. This influence increases with slag content.Iin the same sense the water penetration,resistance was increased by 121%.
The corrosion activity was monitored using half cell potential and linear polarization resistant techniques.Also, an indirect method to evaluate the chloride,corrosion of steel reinforcement was tested.The corrosion potential of steel in GGBS mortar was more than -270mVSCE,which is the ASTM C876 criterian.This indicates the critertia as given by
ASTM cannot be used for the types of cements tested here.The corrosion rates for reinforcing steel in GGBS mortar were lower than the corrosion rates in plain cement mortars.Visual examination of reinforced steel bars taken from GGBS mortars immersed in 3.5 sodium chloride solution for 2 years,didnot indicate corrosion activity.
Key Words: blended cements;blast furnace slag;corrosion;chloride diffusion;water absorption.
Issue 1, January 1998
THE USE OF A GENETIC ALGORITHM IN SOLID WASTE COLLECTION ANALYSIS
L. Yu Lin
S. Malasri
Department of Civil & Environmental Engineering
Christian Brothers University
Memphis, Tennessee, U.S.A.
ABSTRACT
This paper describes the development of a computer simulation system CBU-EXPRESS that was used in the layout of a collection route for a solid waste system. CBU-EXPRESS consists of three components: a mapping module, a database module, and a genetic algorithm modeling module. The mapping module was used to map and to view the selected collection route for a solid waste system. The database module calculated distance among collection spots. The genetic algorithm modeling module provided an analysis procedure to find the optimum collection route. To illustrate the efficiency of CBU-EXPRESS, the model was verified in the field. The results demonstrated that CBU-EXPRESS is a potential tool in solid waste collection analysis. It will provide a reasonable and quick solution for a solid waste collection routing analysis.
Key Words: Solid waste collection, genetic algorithm, artificial intelligence, modeling
ALTERNATIVES TO MEDICAL WASTE INCINERATORS
Ira F. Salkin, Ph.D.
Wadsworth Center, New York State Department of Health
Albany, NY, USA
Edward Krisiunas, MT (ASCP), M.PH, CIC
Spectrum
Burlington, CT, USA
ABSTRACT
Since the introduction of the Resource Conservation and Recovery Act in 1976, the federal Environmental Protection Agency (EPA) has been involved in various aspects of the management of medical waste. Even after the “sunset” of the Medical Waste Tracking Act of 1988, the EPA has contributed to such medical waste issues as defining its solid and liquid components, describing acceptable methods for its processing and transportation, and outlining selection/evaluation criteria for treatment technologies. In this regard, the EPA recently proposed new, more stringent standards for the operation of medical waste incinerators. Owing to the potential negative financial impact of these federal regulations, healthcare facilities, transporters, and disposal companies have begun to evaluate alternative methods for the treatment of medical waste. In this report, we will discuss; (1) the types of alternative methods currently available, (2) the EPA’s evaluation of the application of several of these treatment technologies as alternatives to incineration, and (3) the criteria which may be used to select the most effective system for use in on-site and off-site treatment of medical waste.
Key Words: Medical waste, treatment, alternative technologies, selection criteria
LEACHING TESTS ON SOLIDIFIED PRODUCTS
R. Gavasci, Associate Professor
Faculty of Engineering – University of Rome
“Tor Vergata”
F. Lombardi, Technical Director
Hospital Solid Waste Incineration Plant
AMA, Rome
A. Polettini, Ph.D. Student, P. Sirini, Researcher
Faculty of Engineering – University of Rome “La Sapienza”, ITALY
ABSTRACT
This work shows the experimental results obtained by a series of extended-time leaching tests carried out on stabilized/solidified (S/S) products.
The materials subjected to the leaching tests were obtained by mixing different amounts of Portland cement (C) with fly ash (FA) coming from a Hospital Solid Waste (HSW) incineration plant.
Ideally, as far as contaminant release from the waste is concerned, a leaching test must be able to determine the following characteristics: 1) the compounds that can be released from the waste; 2) the maximum concentration of these compounds in the leachate; 3) the quantities released per unit mass of waste; 4) the release rate of these compounds; 5) the effects of a co-disposal of the waste.
The aspect regarding concentration is relevant because the toxic effects of a number of elements, like most chemical reactions, depend on concentration.
As far as the amount of release is concerned, the necessity to evaluate the maximum amount of hazardous compounds leachable from a waste under different environmental conditions is evident; moreover, it would be important to determine the possibility of accumulation of toxic compounds due to biological and chemical reactions.
Furthermore, the trend of release is related to eventual physical and chemical changes occurring in the waste because of contaminant leaching from the waste matrix.
The procedures applied in carrying out the extended-time leaching tests on S/S products made with HSW fly ash and Portland cement were a modified version of the IRSA – CNR acetic acid leaching test (Italian law standard leaching test) and a modified version of the proposed standard European leaching test (option C).
The tests were carried out over a thirty-day period by renewing the leaching solution every 24 hours.
The comparison between the extended-time and the standardized tests allowed the leaching rate for different contaminants and the leaching – controlling process to be determined.
Key Words: Fly ash, solidification/stabilization, heavy metals, leaching, diffusion
MULTIVARIATE DATA ANALYSIS (MVDA) IN LANDFILL RESEARCH
Holger Ecke, Anders Bergman & Anders Lagerkvist
The Landfill Group
Luleå University of Technology
SE-971 87 Luleå
Sweden
ABSTRACT
Multivariate data analysis (MVDA), a new statistical approach in terms of landfill research, was performed at the evaluation of data sets from three investigations. The interrelationships among variables as well as variation between observations could be examined. Causal relations between experimental factors and response variables have been identified using scatterpott interpretation. The ease of using MVDA at data evaluation is proved. MVDA techniques as follows were applied: principal component analysis (PCA), partial least squares modelling (PLS) and partial least squares discriminant analysis (PLS-DA).
Key Words: Discriminant analysis, landfill, multivariate data analysis, partial least squares, principal component analysis
NEW PROPOSALS FOR INTEGRATED MSW MANAGEMENT IN LANDFILL
M. C. Zanetti and R. Conti
Dept. Georisorse e Territorio
C.so Duca degli Abruzzi 24
10129 Torino, Italy
ABSTRACT
A study was done concerning the economic feasibility of biogas collection with integrated compost production and differentiated recycling collection for a landfill in Italy. Biogas production was estimated by means of modeling which considered waste composition, rate and climatic conditions. An economic evaluation of different alternatives for utilization of recovered biogas was performed.
Key Words: MSW planning; landfill gas; composting; recycling; Italy
SCRAP TIRE DISPOSAL: I. SURVEY OF STATE PROGRAMS
Salim Douglah
Oklahoma Corporation Commission
2102 Lincoln Blvd.
Oklahoma City, OK 73105
Jess W. Everett, Ph.D., P.E.
Associate Professor
Civil and Environmental Engineering
Rowan University
Glassboro, NJ 08028
ABSTRACT
Scrap Tires represent an environmental, human health, and aesthetic problem. Proper management of the millions of scrap tires that are generated in the U.S., as well as the billions of scrap tires that exist in illegal tire dumps throughout the country, is necessary in order to mitigate the threats posed by this special waste. Most states have recently implemented programs to address scrap tire management. In this paper, scrap tire end use markets are briefly introduced, followed by presentation of results from a survey of all 50 state scrap tire program coordinators. Survey results identify preferred funding strategies, use of funds, tire exemption issues, financial incentives for processing and end use, illegal dump cleanup, marketing issues, etc. In a second paper, a case study of a state program is presented, followed by conclusions for both papers in the form of scrap tire program recommendations.
SCRAP TIRE DISPOSAL (II): CASE STUDY AND RECOMMENDATIONS
Jess W. Everett, Ph.D., P.E.
Associate Professor
Civil and Environmental Engineering
Rowan University
Glassboro, NJ 08028
Salim Douglah
Oklahoma Corporation Commission
2102 Lincoln Blvd.
Oklahoma City, OK 73105
ABSTRACT
Scrap tires represent an environmental, human health, and aesthetic problem. Proper management of the millions of scrap tires that are generated in the U.S., as well as the billions of scrap tires that exist in illegal tire dumps throughout the country, is necessary in order to mitigate the threats posed by this special waste. Forty-seven states have recently implemented programs to address scrap tire management; only Alabama, Alaska, and Delaware do not have programs. In the first paper, scrap tire end use markets were briefly introduced, followed by a presentation of results from a survey of all 50 state scrap tire program coordinators. Survey results identified preferred funding strategies, use of funds, tire exemption issues, financial incentives for processing and end use, illegal dump cleanup, marketing issues, etc. In this paper, a case study of the Oklahoma scrap tire program is presented, followed by conclusions for both papers in the form of scrap tire program recommendations. Program objectives should include the proper management of newly scrapped tires and tires in illegal dumps. To meet objectives proper attention should be paid to funding, illegal dump cleanup policies; incentives and market development; regulation of proper tire management; and distribution of funds between illegal dump clean-up and proper management.
SOLID WASTE MANAGEMENT IN SOUTHERN THAILAND
Somtip Danteravanich, D.Eng.
Faculty of Environmental Management
Cherdchan Siriwong, M.Sc.
Faculty of Environmental Management
Prince of Songkla University
Hat Yai, Songkhla
Thailand
ABSTRACT
The Southern region of Thailand is located on the peninsula bordered by Malaysia, the Gulf of Thailand and the Andaman Sea. Its population is about 7.8 million. The amount of solid waste in Southern Thailand has increased exponentially. As a consequence, it has also polluted natural resources and the environment.
This paper aims to report the state of solid waste management in Southern Thailand. The generation, characteristics, resource recovery and disposal of solid waste are presented. The current Policy and Plan of Enhancement and Conservation of National Environmental Quality (1997 – 2016), which emphasizes sustainable strategies for tackling solid waste, is described. In addition, a crucial issue of public protests against the establishment of disposal sites is included. Finally, certain alternative directions of solid waste management appropriate with local conditions are discussed.
Key Words: Municipal solid waste, Domestic hazardous waste, Solid waste management, Recycling, Solid waste disposal, Southern Thailand