Solid waste, municipal

Mumetal Plus Mumiia Mumps Munich beers Municipal solid waste... 

Of the 200 million tons of municipal solid waste collected in the United States in 1993 (1), 22% was recycled while 62% was placed in landfills and 16% incinerated (2). Plastics comprised 9.3% of these materials. The number of U.S. residential collection programs increased from 1,000 in 1988 to more than 7,000 involving more than 100 million people in 1993 (2). Approximate 1994 U.S. recycling rates are given in Table 1. 

When processing municipal solid wastes, an eddy current separation unit is often used to separate aluminum and other nonferrous metals from the waste stream. This is done after removal of the ferrous metals (see Fig. 1). The eddy current separator produces an electromagnetic field through which the waste passes. The nonferrous metals produce currents having a magnetic moment that is phased to repel the moment of the appHed magnetic field. This repulsion causes the nonferrous metals to be thrown out of the process stream away from nonmetallic objects (13). 

Includes hydioelectiic, geothernial, wood, wood waste, municipal solid waste, other biomass, and solar and wind power. 

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

Municipal Solid Waste. In the eady 1990s, the need to dispose of municipal soHd waste (MSW) ia U.S. cities has created a biofuels industry because there is Htde or no other recourse (107). Landfills and garbage dumps are being phased out ia many communities. Combustion of MSW, ie, mass-bum systems, and RDF, ie, refuse-derived fuel, has become an estabhshed waste disposal—energy recovery industry. 

Table 1. Product Composition for Municipal Solid Waste, Wt %...

Table 9. Trace Metals in Municipal Solid Waste and Solid Waste Ash, ppm by wt...

Characterisation of Products ContainingMercury in Municipal Solid Waste in the Ended States, 1970—2000, OSW No. EPA530-R-92-013 (NTIS No. PB92-162 569), U.S. Environmental Protection Agency, Washington, D.C., 1992. 

Fig. 1. Municipal solid waste management system where ( ) indicates recycling options and (-), optional transfer.

Fig. 3. Materials recovery, composting, combustion, and discards of municipal solid waste from 1969 to 2000 (1995—2000 estimated) as a fraction of total generation, where A represents landfill and other B, combustion C, recovery for recycling and D, recovery for composting.

H. Alter, The Greatly Growing Garbage Problem A. Guide to Municipal Solid Waste Management For Communities and Businesses U.S. Chamber of Commerce, Washington, D.C., 1988. 

U.S. Congress, Office of Technology Assessment, Facing America s Trash What Nextfor Municipal Solid Waste OTA-O-424, U.S. Government Printing Office, Washington, D.C., 1989. 

P. J. Knox ed.. Resource Recovery of Municipal Solid Waste, American Institute of Chemical Engineers, New York, 1988. 

K. L. Chumey, A. E. Ledford, S. S. Bmce, and E. S. Domalski, The Chlorine Content of Municipal Solid Waste from Baltimore County, May land and Brooklyn, New York, National Bureau of Standards, Gaithersburg, Md., Apr. 1985. 

R. S. Magee, Plastics in Municipal Solid Waste Incineration A Eiterature Study, Hazardous Substance Management Research Center, New Jersey Institute of Technology, Mar. 1989. 

Hammer Crusher (Fig. 20-27) Pivoted hammers are mounted on a horizontal shaft, and crushing takes place by impact between the hammers and breaker plates. Heavy-duty hammer crushers are frequently used in the quarrying industiy, for processing municipal solid waste, and scrap automobiles. 

FIG. 20-60 Hammer wear as a consequence of shredding municipal solid waste. Sa-oage and Diaz, Proceedings ASME National Waste Processing Conference, Denver, CO, 361-373, 1986.)... 

Individual components. Components that typically make up most industrial and municipal solid wastes and their relative distribution are reported in Table 25-50. Although any number of components could be selected, those listed in the table have been chosen because they are readily identifiable, are consistent with component categories reported in the literature, and are adequate for the characterization of solid wastes for most applications. 

From McGinely, P. M. and Kmet, P, Formation Characteristics, Treatment, and Disposal of Leachate from Municipal Solid Waste Landfills, Bureau of Solid Waste Management, Wisconsin Department of Natural Resources, Madison, 1984. 

LandtiUing of Hazardous Wastes In many states, the only disposal option available for most hazardous wastes is landfilling. The basis for the management of hazardous-wastes landfills is set forth in the Resource Conservation and Recovery Act of 1976. In general, disposal sites for hazardous wastes shoiild be separate from sites for municipal solid wastes. If separate sites are not possible, great care must be taken to ensure that separate disposal operations are maintained. 

The specific molecular mechanisms by which PCDDs and PCDFs are initially formed and become part of the PIC remain largely unknown and are theoretical. The theoretical basis for conjecture is derived primarily from direct observations in municipal solid waste incinerators. The emissions of... 

Venmri scrubbers have been applied to control PM emissions from utility, industrial, commercial, and institutional boilers fired with coal, oil, wood, and liquid waste. They have also been applied to control emission sources in the chemical, mineral products, wood, pulp and paper, rock products, and asphalt manufacrnring industries lead, aluminum, iron and steel, and gray iron production industries and to municipal solid waste incinerators. Typically, venturi scrubbers are applied where it is necessary to obtain high collection efficiencies for fine PM. Thus, they are applicable to controlling emission sources with high concentrations of submicron PM. 

At the low end is the United States, where biomass energy accounted for only about 3 percent (2.7 quadrillion Btus) of the total energy consumption in 1997. However, biomass use had been rising over the previous five years at an average rate of about 1 to 2 percent per year, but fell in 1997 due to a warmer-than-average heating season. Bioenergy produced in the United States is primarily from wood and wood waste and municipal solid waste. 

In the United States about 3 percent of all electricity produced comes from renewable sources of this a little more than half comes from biomass. Most biomass energy generation comes from the lumber and paper industries from their conversion of mill residues to in-house energy. Municipal solid waste also is an important fuel for electricity production approximately 16 percent ot all municipal solid waste is disposed of by combustion. Converting industrial and municipal waste into bioenergy also decreases the necessity for landfdl space. 

Use of some biomass feedstocks can increase potential environmental risks. Municipal solid waste can contain toxic materials that can produce dioxins and other poisons in the flue gas, and these should not be burned without special emission controls. Demolition wood can contain lead from paint, other heavy metals, creosote, and halides used in presen a-tive treatments. Sewage sludge has a high amount of sulfur, and sulfur dioxide emission can increase if sewage sludge is used as a feedstock. 

Economics for generating electricity from biogas can be favorable. Landfill gas from municipal solid waste can supply about 4 percent of the energy consumed in the United States. In 1997, a total of 90 trillion Btus were generated by landfill gas, about 3 percent of total biomass energy consumption. 

Simplified in process terms, RDF involves processing the incoming municipal solid waste (MSW) stream to remove a substantial portion of the noncombustible components, namely aluminum, ferrous, glass and dirt. Various sources list these components in the range as follows ... 

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