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Waste management
From Wikipedia, the free encyclopedia
For the company, see Waste Management, Inc. For other uses, see Waste management (disambiguation). Not to be confused with Sanitary engineering.
| This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. (May 2011)|

Waste management in Kathmandu (Nepal)

Waste management in Stockholm,Sweden
Waste management is the collection, transport, processing or disposal, managing and monitoring of waste materials. The term usually relates to materials produced by human activity, and the process is generally undertaken to reduce their effect on health, the environment or aesthetics. Waste management is a distinct practice from resource recovery which focuses on delaying the rate of consumption of natural resources. All wastes materials, whether they are solid, liquid, gaseous or radioactive fall within the remit of waste management Waste management practices can differ for developed and developing nations, for urban and rural areas, and for residential and industrial producers. Management of non-hazardous waste residential and institutional waste in metropolitan areas is usually the responsibility of local governmentauthorities, while management for non-hazardous commercial and industrial waste is usually the responsibility of the generator subject to local, national or international controls. Contents  [hide]  * 1 Methods of disposal * 1.1 Landfill * 1.2 Incineration * 1.3 Recycling * 1.4 Sustainability * 1.4.1 Biological reprocessing * 1.4.2 Energy recovery * 1.5 Resource recovery * 1.6 Avoidance and reduction methods * 2 Waste handling and transport * 3 Technologies * 4 Waste management concepts * 5 Scientific journals * 6 See also * 7 References * 8 External links| -------------------------------------------------

[edit]Methods of disposal
[edit]Landfill
Main article: Landfill

Landfill operation in Hawaii.

A landfill compaction vehicle in action.

Spittelau incineration plant in Vienna
Disposal of waste in a landfill involves burying the waste, and this remains a common practice in most countries. Landfills were often established in abandoned or unused quarries, mining voids or borrow pits. A properly designed and well-managed landfill can be a hygienic and relatively inexpensive method of disposing of waste materials. Older, poorly designed or poorly managed landfills can create a number of adverse environmental impacts such as wind-blown litter, attraction of vermin, and generation of liquid leachate. Another common product of landfills is gas (mostly composed of methaneand carbon dioxide), which is produced as organic waste breaks down anaerobically. This gas can create odor problems, kill surface vegetation, and is a greenhouse gas. Design characteristics of a modern landfill include methods to contain leachate such as clay or plastic lining material. Deposited waste is normally compacted to increase its density and stability, and covered to prevent attracting vermin (such as mice or rats). Many landfills also have landfill gas extraction systems installed to extract the landfill gas. Gas is pumped out of the landfill using perforated pipes and flared off or burnt in a gas engine to generate electricity. [edit]Incineration

Main article: Incineration
Incineration is a disposal method in which solid organic wastes are subjected to combustion so as to convert them into residue and gaseous products. This method is useful for disposal of residue of both solid waste management and solid residue from waste water management.This process reduces the volumes of solid waste to 20 to 30 percent of the original volume. Incineration and other high temperature waste treatment systems are sometimes described as "thermal...
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