Combustion
Related Topics
Combustion and Incineration Regulations: 40 CFR Part 60 (Subchapter C—Air Programs)
Combustion and incineration regulations are codified in 40 CFR Part 60,
including emissions guidelines and compliance times for municipal waste
combustors.
Guidance for the Sampling and Analysis of Municipal Waste Combustion Ash for the Toxicity Characteristic (PDF) (28 pp, 1.0 MB, About PDF)
Electricity from Municipal
Solid Waste (MSW)
This EPA Web site explains how MSW can be directly combusted in waste-to-energy
facilities to generate electricity. Because no new fuel sources are used
other than the waste that would otherwise be sent to landfills, MSW is
often considered a renewable power source.
Research on
Municipal Waste Combustion (MWC) Pollutant Formation and Control Mechanisms
EPA's Air Pollution Technology Branch (part of EPA's National Risk
Management Research Laboratory) conducts research on air pollutant emissions
generated during the process of municipal solid waste combustion.
To reduce waste volume, local governments or private operators can implement a controlled burning process called combustion or incineration. In addition to reducing volume, combustors, when properly equipped, can convert water into steam to fuel heating systems or generate electricity. Incineration facilities can also remove materials for recycling.
Over one-fifth of the U.S. municipal solid waste incinerators use refuse derived fuel (RDF). In contrast to mass burning—where the municipal solid waste is introduced "as is" into the combustion chamber—RDF facilities are equipped to recover recyclables (e.g., metals, cans, glass) first, then shred the combustible fraction into fluff for incineration.
A variety of pollution control technologies significantly reduce the gases emitted into the air, including:
- Scrubbers—devices that use a liquid spray to neutralize acid gases
- Filters—remove tiny ash particles
Burning waste at extremely high temperatures also destroys chemical compounds and disease-causing bacteria. Regular testing ensures that residual ash is non-hazardous before being landfilled. About ten percent of the total ash formed in the combustion process is used for beneficial use such as daily cover in landfills and road construction.