Municipal solid waste pyrolysis

R. S. Burton, R. C. Baihe and P. Bo, Municipal solid waste pyrolysis. Fluidisation and Fluid Particle Systems, AIChemE Symposium Series, No. 141, 70, 116-123, (1973). 

Although under certain experimental condition, step 2 or step 3 may be ignored due to its non-conspicuous influence to the flnal pyrolysis product distribution, however, a good mathematical model for biomass pyrolysis should be versatile applicable to other pyrolysis conditions, and thus it should be involved the above-mentioned three steps of process, of course heat and mass transfer equations should be included also. This paper presents this kind of mathematical model. Although the model is constructed based on sawdust pyrolysis, it is quite straightforward to apply the same approach to other cases such as straw and municipal solid waste pyrolysis even if to biomass or coal gasification or metal ore reduction. 

Table 15. Product Yields from Pyrolysis of Municipal Solid Waste Organics ...

An Ecoprofile is an assessment of the environmental and resource impacts of a waste disposal process. This paper describes ecoprofiles for six different ways of disposing the plastic fraction in municipal solid waste -two material recycling processes that include separation of the plastic waste, material recycling without separation of the plastic waste, pyrolysis, incineration with heat recovery, and landfill. 17 refs. 

Tables 4.4 and 4.5 show the effect of temperature on product yield and composition from the pyrolysis of mixed municipal solid waste (MSW) and bituminous coal. Other data11 show that beyond a certain temperature char yield does...

Mitsui Engineering and Shipbuilding Co., Ltd. (MES) of Japan has developed and commercialized a pyrolysis process for processing municipal solid waste (Figure 4.1). The process,... 

The process is used on petroleum sludges, used tires, biomedical waste, automobile shredder residues, bark residues and municipal solid wastes. It is limited to treating organic wastes and contaminated soil. For soil contaminated by polychlorinated biphenyls (PCBs), vacuum pyrolysis cannot destroy the PCBs but will concentrate them in the pyrolytic oils. The process cannot be used to treat mine tailings. 

Table 11.3 shows the yield of gas, oil/wax and char from the fixed bed pyrolysis of the main polyalkene plastics, polyethylene and polypropylene, found in municipal solid waste [7-15], Table 11.4 shows the gas, oil/wax and char from the pyrolysis of other plastics [7-9, 14-17], All of the plastics produced an oil/wax and gas and in some cases a char. The product yield related directly to the type of plastic, the reactor type... 

The pyrolysis of mixtures of single plastics and real-world plastic derived from municipal solid waste has been investigated by several researchers and the yield of gas, oiFwax... 

Patent US 6,152,306 describes a whole plant for the reduction of municipal solid waste, including plastics. The plant is said to include a microwave reduction chamber in which pyrolysis presumably occurs. However the document did not contain any detail regarding the chemical reactions or the mechanisms involved [123]. 

Pyroprobe 1000 from CDS) [20] is shown in Figures 18.4.1 and 18.4.2. Figure 18.4.1 shows the yield in several pyrolysis products obtained from almond shells at 850 C, and Figure 18.4.2 shows the same results for municipal solid waste. 

Figure 18.4.2. Comparison between the pyrolysis products yields from a fluidized bed reactor (diamonds) and a filament heated flash pyrolysis (squares) [20] performed at 85(f C for municipal solid waste.

Other materials in waste that is thermally processed also were studied by pyrolytic techniques, typically with the purpose of regenerating the monomers or of obtaining other useful small molecules. For example, pyrolytic studies were performed for the evaluation of the possibilities for re-utilization of nylon carpet waste [7], the recycling of thermoset polymeric composites [8], the recovery of methyl methacrylate from poly(methyl methacrylate) waste [9], as well as for other raw material recovery from pyrolysis of plastic waste [10]. The results of incineration of various other types of waste also were studied at model scale [11, 12). These studies were applied to specific waste materials associated with the manufacturing process or to municipal solid waste [13-15)... 

Most of the effort at China Lake was directed toward demonstrating, at the bench scale, that polymer gasoline could indeed be made noncatalytically from the olefins formed by the selective pyrolysis of municipal solid waste (MSW). Funding for the bench-scale demonstration was provided by the Industrial Environmental Research Laboratory (IERL) of the Environmental Protection Agency, beginning in 1975 (EPA-IAG-D6-0781). 

The first unit operation in the production of waste or biomass derived activated carbon is pyrolysis, also known as baking or charring. In this process the material is heated in an essentially oxygen-free atmosphere to drive off the free moisture and volatiles. The material that remains is called char or fixed carbon. The char yield is dependent upon heating rate and in a study performed by Roberts et al. (1978) on the production of municipal solid waste derived activated carbon, the following... 

Another application of OEC to overcome thermal limitations is in thermal pyrolysis of municipal solid waste or refuse-derived fuel (RDF).3 The N2 in air... 

The pyrolysis of municipal solid waste (MSW) Is a promising method of producing useful fuels. However, the reaction mechanisms are not well understood. Current DOE/ANL research Is directed at gaining a better understanding of the basic thermoklnetlc mechanisms associated with the pyrolytic conversion of MSW. 

Kelt, J E et al Pyrolysis of Municipal Solid Wastes Argonne National Laboratory, ANL/CNSV-45, (1984). 

Evans, R. J. et al. Atlas of the Primary Pyrolysis Products of Municipal Solid Waste and Selected Constituents Solar Energy Research Institute, SERI/SP-234-2597, (1984). 

Helt, J. E. et al. Pyrolysis of Municipal Solid Waste Annual Report July 1984-June 1985 Argonne National Laboratory, ANL/CNSV-54 (1986). 

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