Decisional Model For Integrated Management Of Muncipal Solid Waste—A Case Study

Explosion Hazards And Explosion Protection During The Construction Of Landfill-Gas-Wells

Industrial Solid Waste Management And Joint Production

Lead-Contaminated Soil Disposal In Non-Hazardous Waste Landfills--Groundwater Effects  And Policy Implications

Measurement Of Dioxins In Waste Incinerator Fly Ash Residues And Their Destruction By Sintering

Odour Impact Evaluation Of Municipal Waste Composting Unit
 
 

G. d’Antonio, M. Fabbricino, F. Pirozzi
Department of Hydraulic and Environmental Engineering ‘Girolamo Ippolito’
University of Naples ‘Federico II’
via Claudio 21
80125 - Naples, ITALY

ABSTRACT
In order to develop an integrated system for solid waste management, the Campania Regional Administration (Italy) has divided the region into two territorial areas. For each of these a decisional model is applied so as to define the composition and the amount of solid waste flows to be collected and diverted to the treatment plants. Six different scenarios are considered, corresponding to the successive phases of Regional Programme implementation. An optimisation algorithm for the solution of the decisional model is used to spread the waste components among the envisaged plants with or without source-separated collection, while imposing four objectives for minimum material recovery. The obtained results are discussed and compared for the assumed cases in order to arrive at the best technical and economic solution of waste management, i.e. compatible with choices made by the Regional Programme, for the different phases of the municipal solid waste management plan.

Key Words: Solid waste, integrated system, decisional model, source separated collection

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Burkhard Forell
Technical University of Braunschweig
Fliederweg 20, D-33100 Paderborn
GERMANY

Prof. Dr. rer. nat. em. Hans Hölemann
Föhrenstrabe 31, D-44289 Dortmund
GERMANY

ABSTRACT
During the construction of landfill-gas wells an atmosphere made up of air and LFG develops inside the borehole in which the content of air decreases with depth. Because LFG has a high content of fuel gases, the atmosphere inside the borehole is partly ignitable. To determine its explosion limits a tenary diagram of air, methane and inert gases is suitable, with the inert gases carbon dioxide, additional nitrogen and water vapor. 
 As ignition sources mechanically caused sparks from the movements of the drilling tool have to be taken into account. Sparks resulting from steel to steel interactions as a rule have insufficient ignition energy. Therefore probably only certain material combinations like iron grate and light metals provide incendive sparks. 
 Filling in the aggregate into the borehole has reportedly lead to ignitions.
 The intensity of an explosion inside the borehole depends on different influences: 
· an atmosphere of LFG and air sets free relatively small amounts of energy, but
· explosions in pipelines are accompanied by turbulence produced by the axial flows which speed up the explosion.
 Here the volume and the dispersion of the ignitable atmosphere as well as the place of ignition are of great importance. 
Hazards for the drilling personnel and especially the drilling assistant from hurled-out refuse and hot fire gases are to be expected - not, however, that the drilling tool will be pressed out of the borehole by an explosion. 
 A primary measure of explosion protection against the development of ignitable atmosphere above the borehole is the use of fans diluting the outflowing LFG.
Explosion protection inside the borehole is rarely employed. An effective measure would be to render the borehole inert with carbon dioxide or nitrogen. However this measure requires considerable expenditure. 

Key Words: Landfill, Landfill-Gas, LFG, Explosion, Explosion Protection, Well, Drilling, Ignition Source, Inerting

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Jan Stenis
Department of Technology
University of Kalmar
SE-391 82, Kalmar, Sweden
 

ABSTRACT
The study illustrates how joint production theory can be applied in estimating the profitability of fractionating industrial solid wastes, a given product and the wastes produced in connection with its manufacture being regarded as a production-planning unit. Two case studies showing how the approach described can be applied both to bulk manufacturing and to the manufacture of technically complicated products are presented. The realism of this approach and the contribution it can make to optimizing the separation of industrial solid waste fractions in manufacturing processes of different types, together with associated financial considerations, are discussed.

Key Words: Industrial solid waste management, joint production

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Edward L. Ferguson
Howrey Arnold & White Simon
Washington, DC  USA
 

Mark McBride
Capital Analysis Group
Washington, DC  USA

ABSTRACT
Lead-contaminated soil that fails the Toxicity Characteristic Leaching Procedure (“TCLP”) test must be managed as hazardous waste under the Resource Conservation and Recovery Act (“RCRA”) and disposed in Subtitle C landfills. We examine the actual risk to groundwater from the management and disposal of lead-contaminated soil in non-hazardous waste landfills. Lead concentrations in leachate-affected groundwater were modeled using EPA's Monte Carlo Composite Model for Leachate Migration with Transformation Products (“CMTP”). Simulated leachate concentrations were based on Synthetic Precipitation Leaching Procedure (“SPLP”) and TCLP tests of soil from lead-contaminated Superfund sites. Receptor well lead concentrations were less than the drinking water standard (0.015 mg/L) in 98.5% of the SPLP scenarios, and 96% of the TCLP scenarios. These were more protective than the level EPA used to justify a proposed conditional exclusion from the RCRA hazardous waste program for architectural debris containing lead-bearing paint, allowing disposal of such debris in non-hazardous waste landfills. Since the risks to groundwater from lead-contaminated soil disposal are less than those from architectural debris, EPA should allow lead-contaminated soil that fails the TCLP to be disposed in non-hazardous waste landfills. This would reduce the costs of its management and encourage greater remediation of lead soil hazards.

Key Words: Lead, soil contamination, soil disposal, groundwater, leachate, leaching tests

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D. B. Ward, P. H. Lee, V. Nasserzadeh, J. Swithenbank
Sheffield University Waste Incineration Centre (SUWIC)

C. W. McLeod, P. Clarkson
Centre for Analytical Sciences (CAS), Sheffield University

John Upton
Varian Analytical Instruments

John Laming, Mike Holmes
Dyson Hotwork Engineering

ABSTRACT
The waste incineration industry is faced with ever more demanding environmental legislation regarding its wastes. One example is the new European dioxin limit of 0. 1 ng/Nm3 ITEQ (International Toxic Equivalent Quantity) in atmospheric emissions. This has added to demands for further investigation into the formation, prevention and removal of dioxins in all aspects of waste incineration. Modern incinerator gas cleaning plants have proved extremely successful in reducing polluting emissions to atmosphere; however, the toxic fly ash residues generated by such systems pose a significant disposal problem. Waste incineration will only gain full public acceptance if the innocuous quality of all outputs can be guaranteed. At present the ash produced by the waste incineration industry is landfilled but at considerable cost due to toxic heavy metals and organics content. Detoxified ash would prove cheaper to landfill and may even have potential uses in the construction industry.
 In the past few years, the Sheffield University Waste Incineration Centre (SUWIC) has been carrying out extensive research in order to develop a cheap, reliable and effective technology for the detoxification of incinerator ash. A novel, energy efficient, ash sintering technology has been developed and has shown considerable success in immobilising leachable heavy metal fractions. A series of tests are currently being carried out in order to examine the extent to which dioxins are destroyed by this novel sintering process. This paper presents the results obtained from this study.

Key Words:  Fly ash, Sintering, Dioxins/Furans, Ion trap Mass Spectrometry, Waste Incineration, Heat Regeneration

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Anjali Srivastava, Rakesh Kumar
National Environmental Engineering Research Institute (NEERI)
89-B, Dr. Annie Besant Road
Worli, Mumbai - 400 018, INDIA

R.N.Singh
National Environmental Engineering Research Institute (NEERI)
Nehru Marg, Nagpur - 440 020, INDIA

ABSTRACT
Municipal solid waste composting is becoming an acceptable technical solution for many city municipalities in India. Though composting as an alternative of solid waste management is being accepted readily, odour emission from compost piles and its effect on population has been a major concern.
An attempt has been made to study the odour impact due to compost plant through modeling, using two approaches viz. estimating peak to mean ratio for comparison with odour threshold values and estimation of plume width along with odour threshold concentration.
The study indicates that predictions of odour impact by two approaches give fairly good agreement. However, plume width approach does not provide information regarding duration of occurrence of various odour levels. In the other approach of peak to mean ratio estimation, estimation of intensity of fluctuation accounts for variation in concentrations away from the mean value. 
Odour response appears to relate to fluctuations of concentrations around the mean values. The concept of peak to mean ratio provides better objectivity in identifying odour impact areas.

Key Words: Odour Dispersion, Composting, Municipal Solid Waste

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