In the last decade of the nineteenth century, the English seaside and health resort of Torquay abandoned its old practice of municipal waste tipping and invested in a destructor, or incinerator. Technical, legal and financial considerations lay behind this decision. The ensuing protests against the operation of the destructor highlight the tensions between nascent technocrats and the affected residents. At a time when pollution was most often displaced or dispersed, topography conspired against the residents of Torquay, and challenged the accepted spatial and social relationships of waste.
The objective of this study is to explore the potential of producing energy from open-dump solidwaste from Rajamangala University of Technology Isan Surin Campus. Heating value as well as thephysical and chemical compositions were analyzed. The composition and heating value were comparedto refuse-derived fuel quality standard. All waste samples were separated into combustible and non-com-bustible matter. Paper, plastic, food residue, textiles, rubber and leather were classified as combustible. In excess of ninety-nine (99%) of open dump waste consisted of combustible matteras follows: mixed plastic (45%), textile (19%), food residue (18%), paper (14%), and leather and rubber (3%). Non-combustible composted inert material consisted of only 1% of the open-dump solid waste. Moisture and total solid contents of open-dump solid waste were 51.6% and 48.4% (wet basis) respectively. Volatile matterand ash contents of those were 95.14% and 4.37% (dry basis) respectively. The heating value of the open-dump solid waste was 29 MJ kg-1, which is higher than the refusederived fuel quality standard and re-sults reported in earlier studies [8,10,14]. This indicated the potential of open-dump solid waste to produce refuse-derived fuel (RDF). Therefore, it is possible that energyrecovery through RDF production can be an effective waste management option for Rajamangala University of Technology Isan,Surin Campus. Further study should focus on production of RDF in terms of moisture content removal and compositions of RDF. Furthermore, characteristics of RDF should be determined to explore alter-native sources of renewable energy.
Conditioning of sludges improves dewatering characteristics and reduces the quantity of sludge to be handled. Anaerobic digested sludge collected from a sewage treatment plant contained 1.8% to 8% oil. The increase of specific resistance and capillary suction time (CST) with increasing oil content observed in these samples indicates the interference of oil in dewatering. It has been found that addition of municipal solid wastes incinerator fly ash decreases the specific resistances and capillary suction times of oily sludges rapidly up to 3% dosage. Beyond 3% fly ash, the decrease is less significant and the solids content in the sludge cake increases. This optimum dosage remains the same for sludges with varying oil contents from 1.8% to 12%. The total suspended solids of filtrate decreases with fly ash dosage but the toxic concentrations of heavy metals increases considerably. However at the optimum dosage of 3%, concentrations of heavy metals are within the limits for discharging into the sewers. The correlations of CST with the dewatering characteristics such as specific resistance, filter yield and corrected filter yield are established. These correlations can be used to obtain a quick prediction on dewaterability.
The results of a two-year pilot-scale investigation on codisposal of an industrial metal treatment sludge with municipal refuse under the influence of leachate containment and recycle are used to reveal the environmental consequences of heavy metals on such a landfill management practice. Comparisons between landfill simulators with and without varying metal sludge admixtures have provided an opportunity for examination of selected testing methodologies and parameters descriptive of inherent physical-chemical and microbially mediated reactions prevailing throughout the progress of landfill stabilization. Collectively, these analyses were sufficient to determine landfill assimilative capacity in terms of several controlling mechanisms including: potential inhibition of waste stabilization by mobilized heavy metals; precipitation, immobilization, and detoxification of heavy metals by entrapment and filtration; encapsulation and isolation of heavy metals by reaction with carbonates and sulfides; and formation of less toxic metal complexes with humiclike substances and potential for remobilization without transport phase regulation. On the basis of these results, a method for the determination of sludge loadings and their effects at both present and future landfill codisposal sites could be proposed.