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Municipal solid waste

(Redirected fromMunicipal waste)
"Municipal waste" and "Urban waste" redirect here. For other uses, seeMunicipal waste (disambiguation).For the punk band, seeUrban Waste (band).

Municipal solid waste(MSW), commonly known astrashorgarbagein theUnited StatesandrubbishinBritain,is awaste typeconsisting of everyday items that are discarded by the public. "Garbage"can also refer specifically tofood waste,as in agarbage disposal;the two are sometimes collected separately. In the European Union, the semantic definition is 'mixed municipal waste,' given waste code 20 03 01 in the European Waste Catalog. Although the waste may originate from a number of sources that has nothing to do with a municipality, the traditional role of municipalities in collecting and managing these kinds of waste have produced the particular etymology 'municipal.'

Composition

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The composition of municipal solid waste varies greatly frommunicipalityto municipality,[1]and it changes significantly with time. In municipalities which have a well-developed waste recycling system, the waste stream mainly consists of intractable wastes such asplastic filmand non-recyclablepackaging materials.At the start of the 20th century, the majority of domestic waste (53%) in the UK consisted ofcoal ashfrom open fires.[2] In developed areas without significant recycling activity it predominantly includesfood wastes, market wastes, yard wastes,plastic containersand product packaging materials, and other miscellaneous solid wastes from residential, commercial, institutional, and industrial sources.[3]Most definitions of municipal solid waste do not includeindustrial wastes,agricultural wastes,medical waste,radioactive wasteorsewage sludge.[4]Waste collection is performed by themunicipalitywithin a given area. The termresidual wasterelates to waste left from household sources containing materials that have not been separated out or sent for processing.[5]Wastecan be classified in several ways, but the following list represents a typical classification:

For example, typical municipal solid waste in China is composed of 55.9% food residue, 8.5% paper, 11.2% plastics, 3.2% textiles, 2.9% wood waste, 0.8% rubber, and 18.4% non-combustibles.[7]

Components of solid waste management

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Bins to collectpaper,aluminium,glass,PET bottlesand incinerable waste

The municipal solid waste industry has four components:recycling,composting,disposal,andwaste-to-energyvia incineration.[8]There is no single approach that can be applied to the management of all waste streams, therefore theEnvironmental Protection Agency,aU.S. federal governmentagency, developed a hierarchy ranking strategy for municipal solid waste.[9]Thewaste management hierarchyis made up of four levels ordered from most preferred to least preferred methods based on their environmental soundness: Source reduction and reuse; recycling or composting;energy recovery;treatment and disposal.[10]

Collection

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The functional element of collection includes not only the gathering of solid waste and recyclable materials, but also the transport of these materials, after collection, to the location where the collection vehicle is emptied. This location may be a materials processing facility, a transfer station or a landfill disposal site.

Waste handling and separation, storage and processing at the source

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Waste handling and separation involves activities associated with waste management until the waste is placed in storage containers for collection. Handling also encompasses the movement of loaded containers to the point of collection. Separating different types of waste components is an important step in the handling and storage of solid waste at the source of collection.

Segregation and processing and transformation of solid wastes

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The types of means and facilities that are now used for the recovery of waste materials that have been separated at the source include kerbside collection, drop-off, and buy-back centres. The separation and processing of wastes that have been separated at the source and the separation of commingled wastes usually occur at a materials recovery facility, transfer stations, combustion facilities, and treatment plants.

Transfer and transport

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This element involves two main steps. First, the waste is transferred from a smaller collection vehicle to larger transport equipment. The waste is then transported, usually over long distances, to a processing or disposal site.

Disposal

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Today, the disposal of wastes by land filling or land spreading is the ultimate fate of all solid wastes, whether they are residential wastes collected and transported directly to a landfill site, residual materials frommaterials recovery facilities(MRFs), residue from the combustion of solid waste,compost,or other substances from various solid waste processing facilities. A modern sanitary landfill is not a dump; it is an engineered facility used for disposing of solid wastes on land without creating nuisances or hazards to public health or safety, such as the problems of insects and the contamination ofgroundwater.

Reusing

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In recent years, environmental organizations, such asFreegleorThe Freecycle Network,have been gaining popularity for their online reuse networks. These networks provide a worldwide online registry of unwanted items that would otherwise be thrown away, for individuals and nonprofits to reuse or recycle. Therefore, this free Internet-based service reduces landfill pollution and promotes thegift economy.

Landfills

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Segregation of Trash

Landfillsare created by land dumping. Land dumping methods vary, most commonly it involves the mass dumping of waste into a designated area, usually a hole or sidehill. After the waste is dumped, it is then compacted by large machines. When the dumping cell is full, it is then "sealed" with a plastic sheet and covered in several feet of dirt. This is the primary method of dumping in the United States because of the low cost and abundance of unused land in North America. Landfills are regulated in the US by theEnvironmental Protection Agency,which enforces standards provided in theResource Conservation Recovery Act,such as requiring liners and groundwater monitoring.[11]This is because landfills pose the threat of pollution and can contaminate groundwater. The signs of pollution are effectively masked by disposal companies, and it is often hard to see any evidence. Usually, landfills are surrounded by large walls or fences hiding the mounds of debris. Large amounts of chemical odor eliminating agent are sprayed in the air surrounding landfills to hide the evidence of the rotting waste inside the plant.[12]

Energy generation

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Municipal solid waste produces enormous amounts ofmethane,a potentgreenhouse gas.[13][14]However, nearly 90% of these methane emissions could be avoided with existing technologies.[14][13]

In particular, municipal solid waste can be used to generate energy because of the lipid content present within it. A lot of MSW products can be converted into clean energy if the lipid content can be accessed and utilized.[15]Several technologies have been developed that make the processing of MSW for energy generation cleaner and more economical than ever before, including landfill gas capture, combustion,pyrolysis,gasification,andplasma arcgasification.[16][17]

While older waste incineration plants emitted a lot of pollutants, recent regulatory changes and new technologies have significantly reduced this concern.United States Environmental Protection Agency(EPA) regulations in 1995 and 2000 under theClean Air Acthave succeeded in reducing emissions ofdioxinsfromwaste-to-energyfacilities by more than 99 percent below 1990 levels, while mercury emissions have been reduced by over 90 percent.[18]The EPA noted these improvements in 2003, citing waste-to-energy as a power source "with less environmental impact than almost any other source ofelectricity".[19]

See also

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References

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  1. ^Kumar, Sunil; Dhar, Hiya; Nair, Vijay V.; Bhattacharyya, J. K.; Vaidya, A. N.; Akolkar, A. B. (2016). "Characterization of municipal solid waste in high-altitude sub-tropical regions".Environmental Technology.37(20): 2627–2637.doi:10.1080/09593330.2016.1158322.PMID26915419.S2CID8140600.
  2. ^Centenary history of waste and waste managers in London and south east England- Page 7Archived2013-08-13 at theWayback Machine
  3. ^Non-hazardous WasteU.S. Environmental Protection Agency, Municipal Solid Waste
  4. ^Municipal Solid WasteArchived2010-11-20 at theWayback MachineU.S. Energy Information Administration
  5. ^Mechanical Biological TreatmentArchived2007-09-27 atarchive.todayWelsh Assembly (2005) Mechanical Biological Treatment, Environment Countryside and Planning Website, Welsh Assembly
  6. ^"Organics -Green Bin".Christchurch City Council.Retrieved19 March2016.
  7. ^Zhou, Hui; Meng, AiHong; Long, YanQiu; Li, QingHai; Zhang, YanGuo (August 2014). "An overview of characteristics of municipal solid waste fuel in China: Physical, chemical composition and heating value".Renewable and Sustainable Energy Reviews.36:107–122.doi:10.1016/j.rser.2014.04.024.
  8. ^Nonhazardous wasteArchived2010-11-20 at theWayback MachineU.S. Energy Information Administration
  9. ^"System Overview > Solid Waste - GSA Sustainable Facilities Tool".sftool.gov.
  10. ^US EPA, OSWER (22 September 2015)."Advancing Sustainable Materials Management: Facts and Figures".US EPA.
  11. ^Horinko, Marianne, Cathryn Courtin."Waste Management: A Half Century of Progress."EPA Alumni Association. March 2016.
  12. ^Rogers, Heather (2006).Gone Tomorrow: The Hidden Life of Garbage.New York: The New Press.ISBN9781595581204.
  13. ^abWebber, Michael; Glazer, Yael (17 November 2023). "Solid waste, a lever for decarbonization".Science.382(6672): 762.
  14. ^abHoy, Zheng Xuan; Woon, Kok Sin; Chin, Wen Cheong; Fan, Yee Van; Yoo, Seung Jick (17 November 2023). "Curbing global solid waste emissions toward net-zero warming futures".Science.382(6672): 797.
  15. ^Caircross, Richard (1 January 2018)."Longitudinal Study of Wastewater Greases and Their Potential for the Production of Biofuels".Energy and Fuels.32(2): 1831–1842.doi:10.1021/acs.energyfuels.7b03550.Retrieved25 February2022.
  16. ^"Environmental and Energy Study Institute Issue Brief"(PDF).
  17. ^Agaton, Casper Boongaling; Guno, Charmaine Samala; Villanueva, Resy Ordona; Villanueva, Riza Ordona (2020-10-01)."Economic analysis of waste-to-energy investment in the Philippines: A real options approach".Applied Energy.275:115265.doi:10.1016/j.apenergy.2020.115265.ISSN0306-2619.
  18. ^US EPA, ORD (26 March 2015)."Research Grants".US EPA.
  19. ^U.S. EPA Letter to Maria Zannes, President, Integrated Waste Services AssociationArchived2011-09-28 at theWayback Machine

Further reading

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