Waste management

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For the company, see Waste Management, Inc. For other uses, see Waste management
(disambiguation).

Not to be confused with Sanitary engineering.

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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 waste 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 wasteresidential and
institutional waste in metropolitan areas is usually the responsibility of local government authorities, while
management for non-hazardous commercial and industrial waste is usually the responsibility of the
generator subject to local, national or international authorities.
 Contents

[hide]

 1 History

o 1.1 Modern era

 2 Methods of disposal

o 2.1 Landfill

o 2.2 Incineration

o 2.3 Recycling

o 2.4 Sustainability

 2.4.1 Biological reprocessing

 2.4.2 Energy recovery

o 2.5 Resource recovery

o 2.6 Avoidance and reduction methods

 3 Waste handling and transport

 4 Technologies

 5 Waste management concepts

 6 Scientific journals

 7 See also

 8 References

 9 External links
History[edit]
Main article: History of waste management

Throughout most of history, the amount of waste generated by humans was insignificant due to
low population density and low societal levels of the exploitation of natural resources. Common waste
produced during pre-modern times was mainly ashes and human biodegradable waste, and these were
released back into the ground locally, with minimum environmental impact. Tools made out
of wood or metal were generally reused or passed down through the generations.

However, some civilizations do seem to have been more profligate in their waste output than others. In
particular, the Maya of Central America had a fixed monthly ritual, in which the people of the village would
gather together and burn their rubbish in large dumps.[1]

Modern era[edit]
Sir Edwin Chadwick's 1842 reportThe Sanitary Condition of the Labouring Population was influential in securing the passage
of the first legislation aimed at waste clearance and disposal.

Following the onset of industrialisation and the sustained urban growth of large population centres
in England, the buildup of waste in the cities caused a rapid deterioration in levels of sanitation and the
general quality of urban life. The streets became choked with filth due to the lack of waste clearance
regulations.[2] Calls for the establishment of a municipal authority with waste removal powers were mooted
as early as 1751 by Corbyn Morris in London, who proposed that "...as the preservation of the health of
the people is of great importance, it is proposed that the cleaning of this city, should be put under one
uniform public management, and all the filth be...conveyed by the Thames to proper distance in the
country".[3]

However, it was not until the mid-19th century, spurred by increasingly devastating cholera outbreaks and
the emergence of a public health debate that the first legislation on the issue emerged. Highly influential
in this new focus was the report The Sanitary Condition of the Labouring Population in 1842[4] of the social
reformer, Edwin Chadwick, in which he argued for the importance of adequate waste removal and
management facilities to improve the health and wellbeing of the city's population.

In the UK, the Nuisance Removal and Disease Prevention Act of 1846 began what was to be a steadily
evolving process of the provision of regulated waste management in London. TheMetropolitan Board of
Works was the first city-wide authority that centralized sanitation regulation for the rapidly expanding city
and the Public Health Act 1875 made it compulsory for every household to deposit their weekly waste in
"moveable receptacles: for disposal—the first concept for a dust-bin.[5]
Manlove, Alliott & Co. Ltd. 1894 destructor furnace. The use of incineratorsfor waste disposal became popular in the late
19th century.

The dramatic increase in waste for disposal led to the creation of the first incineration plants, or, as they
were then called, "destructors". In 1874, the first incinerator was built in Nottingham by Manlove, Alliott &
Co. Ltd. to the design of Albert Fryer.[3] However, these were met with opposition on account of the large
amounts of ash they produced and which wafted over the neighbouring areas.[6]

Similar municipal systems of waste disposal sprung up at the turn of the 20th century in other large cities
of Europe and North America. In 1895, New York City became the first U.S. city with public-sector
garbage management.[5]

Early garbage removal trucks were simply open bodied dump trucks pulled by a team of horses. They
became motorized in the early part of the 20th century and the first close body trucks to eliminate odours
with a dumping lever mechanism were introduced in the 1920s in Britain.[7] These were soon equipped
with 'hopper mechanisms' where the scooper was loaded at floor level and then hoisted mechanically to
deposit the waste in the truck. TheGarwood Load Packer was the first truck in 1938, to incorporate a
hydraulic compactor.

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

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 methane and carbon
dioxide), which is produced as organic waste and breaks down anaerobically. This gas can create odor
problems, kill surface vegetation and is agreenhouse 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.

Incineration[edit]
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 treatment". Incinerators convert waste
materials into heat, gas, steam and ash.

Incineration is carried out both on a small scale by individuals and on a large scale by industry. It is used
to dispose of solid, liquid and gaseous waste. It is recognized as a practical method of disposing of
certain hazardous waste materials (such as biological medical waste). Incineration is a controversial
method of waste disposal, due to issues such as emission of gaseouspollutants.
Incineration is common in countries such as Japan where land is more scarce, as these facilities
generally do not require as much area as landfills. Waste-to-energy (WtE) or energy-from-waste (EfW)
are broad terms for facilities that burn waste in a furnace or boiler to generate heat, steam or electricity.
Combustion in an incinerator is not always perfect and there have been concerns about pollutants in
gaseous emissions from incinerator stacks. Particular concern has focused on some very
persistent organic compounds such as dioxins, furans, and PAHs, which may be created and which may
have serious environmental consequences.

Recycling[edit]
Main article: Recycling

Steel crushed and baled for recycling

Recycling is a resource recovery practice that refers to the collection and reuse of waste materials such
as empty beverage containers. The materials from which the items are made can be reprocessed into
new products. Material for recycling may be collected separately from general waste using dedicated bins
and collection vehicles, a procedure called kerbside collection. In some communities, the owner of the
waste is required to separate the materials into various different bins (e.g. for paper, plastics, metals) prior
to its collection. In other communities, all recyclable materials are placed in a single bin for collection, and
the sorting is handled later at a central facilty. The latter method is known as "single-stream recycling."[8][9]

The most common consumer products recycled include aluminium such as beverage cans, copper such
as wire, steel from food and aerosol cans, old steel furnishings or
equipment,polyethylene and PET bottles, glass bottles and jars, paperboard cartons, newspapers,
magazines and light paper, and corrugated fiberboard boxes.

PVC, LDPE, PP, and PS (see resin identification code) are also recyclable. These items are usually
composed of a single type of material, making them relatively easy to recycle into new products. The
recycling of complex products (such as computers and electronic equipment) is more difficult, due to the
additional dismantling and separation required.

The type of material accepted for recycling varies by city and country. Each city and country has different
recycling programs in place that can handle the various types of recyclable materials. However, certain
variation in acceptance is reflected in the resale value of the material once it is reprocessed.

Sustainability[edit]
The management of waste is a key component in a business' ability to
maintaining ISO14001 accreditation. Companies are encouraged to improve their environmental
efficiencies each year by eliminating waste through resource recovery practices, which are sustainability-
related activities. One way to do this is by shifting away from waste management to resource
recovery practices like recycling materials such as glass, food scraps, paper and cardboard, plastic
bottles and metal.
Biological reprocessing[edit]
Main articles: Composting, Home composting, Anaerobic digestion, and Microbial fuel cell

An active compost heap.

Recoverable materials that are organic in nature, such as plant material, food scraps, and paper products,
can be recovered through composting and digestion processes to decompose the organic matter. The
resulting organic material is then recycled as mulch or compost for agricultural or landscaping purposes.
In addition, waste gas from the process (such as methane) can be captured and used for generating
electricity and heat (CHP/cogeneration) maximising efficiencies. The intention of biological processing in
waste management is to control and accelerate the natural process of decomposition of organic matter.
(See resource recovery).
Energy recovery[edit]
Main article: Waste-to-energy

Anaerobic digestion component ofLübeck mechanical biological treatment plant in Germany, 2007

The energy content of waste products can be harnessed directly by using them as a direct combustion
fuel, or indirectly by processing them into another type of fuel. Thermal treatment ranges from using
waste as a fuel source for cooking or heating and the use of the gas fuel (see above), to fuel for boilers to
generate steam and electricity in a turbine. Pyrolysis and gasification are two related forms of thermal
treatment where waste materials are heated to high temperatures with limited oxygen availability. The
process usually occurs in a sealed vessel under high pressure. Pyrolysis of solid waste converts the
material into solid, liquid and gas products. The liquid and gas can be burnt to produce energy or refined
into other chemical products (chemical refinery). The solid residue (char) can be further refined into
products such as activated carbon. Gasification and advanced Plasma arc gasification are used to
convert organic materials directly into a synthetic gas (syngas) composed of carbon
monoxide andhydrogen. The gas is then burnt to produce electricity and steam. An alternative to pyrolysis
is high temperature and pressure supercritical water decomposition (hydrothermal monophasic oxidation).

Resource recovery[edit]
Resource recovery (as opposed to waste management) uses LCA (life cycle analysis) attempts to offer
alternatives to waste management. For mixed MSW (Municipal Solid Waste) a number of broad studies
have indicated that administration, source separation and collection followed by reuse and recycling of the
non-organic fraction and energy and compost/fertilizer production of the organic material via anaerobic
digestion to be the favoured path.

Avoidance and reduction methods[edit]

Main article: Waste minimization

An important method of waste management is the prevention of waste material being created, also known
as waste reduction. Methods of avoidance include reuse of second-hand products, repairing broken items
instead of buying new, designing products to be refillable or reusable (such as cotton instead of plastic
shopping bags), encouraging consumers to avoid using disposable products (such as disposable cutlery),
removing any food/liquid remains from cans and packaging,[10] and designing products that use less
material to achieve the same purpose (for example, lightweighting of beverage cans).[11]

Waste handling and transport[edit]

Main articles: Waste collection vehicle, Dustbin, and Waste sorting
Molded plastic, wheeled waste bin inBerkshire, England

Waste collection methods vary widely among different countries and regions. Domestic waste collection
services are often provided by local government authorities, or by private companies in the industry.
Some areas, especially those in less developed countries, do not have a formal waste-collection system.
Examples of waste handling systems include:

 In Europe and a few other places around the world, a few communities use a proprietary collection
system known as Envac, which conveys refuse via underground conduits using a vacuum system.
Other vacuum-based solutions include the MetroTaifun® [12] single-line and ring-line automatic waste
collection system, where the waste is automatically collected through relatively small diameter flexible
pipes from waste collection points spread out up to a distance of four kilometres from the waste
collections stations.
 In Canadian urban centres curbside collection is the most common method of disposal, whereby the
city collects waste and/or recyclables and/or organics on a scheduled basis. In rural areas people
often dispose of their waste by hauling it to a transfer station. Waste collected is then transported to a
regional landfill.
 In China, Plastic pyrolysis or Tire pyrolysis is: the process of converting waste plastic/tires into
industrial fuels like pyrolysis oil, carbon black and hydrocarbon gas.End products are used as
industrial fuels for producing heat, steam or electricity. Pyrolysis plant is also known as: pyrolysis unit,
plastic to fuel industry, tire to fuel industry, plastic and tire recycling unit etc.The system is used in
USA, California, Australia, Greece, Mexico, the United Kingdom and in Israel.For example, RESEM
pyrolysis plant that has been operational at Texas USA since December 2011, and processes up to
60 tons per day.[13]
 In Taipei, the city government charges its households and industries for the volume of rubbish they
produce. Waste will only be collected by the city council if waste is disposed in government issued
rubbish bags. This policy has successfully reduced the amount of waste the city produces and
increased the recycling rate.
 In Israel, the Arrow Ecology company has developed the ArrowBio system, which takes trash directly
from collection trucks and separates organic and inorganic materials through gravitational settling,
screening, and hydro-mechanical shredding. The system is capable of sorting huge volumes of solid
waste, salvaging recyclables, and turning the rest into biogas and rich agricultural compost. The
system is used in California, Australia, Greece, Mexico, the United Kingdom and in Israel. For
example, an ArrowBio plant that has been operational at theHiriya landfill site since December 2003
serves the Tel Aviv area, and processes up to 150 tons of garbage a day.[14]
 In Saudi Arabia there is the world’s largest AWCS now being built in the vicinity of Islam’s holiest
mosque (Mecca). During the Ramadan and Hajj 600,000 kilos, or 4,500 cubic meters, of waste is
generated each day, which puts a heavy demand on those responsible for collecting the waste and
litter. In the [12] MetroTaifun Automatic Waste Collection System, the waste is automatically collected
from 74 waste feeding points spread out across the area and then transferred via a 20-kilometre pipe
network to a central collection point, keeping all the waste collecting activities out of sight and below
ground with the central collection point well away from the public areas.
 In San Francisco, the local government established its Mandatory Recycling and Composting
Ordinance in support of its goal of zero waste by 2020, requiring everyone in the city to keep
 recyclables and compostables out of the landfill. The three streams are collected with the curbside
"Fantastic 3" bin system - blue for recyclables, green for compostables, and black for landfill-bound
materials - provided to residents and businesses and serviced by San Francisco's sole refuse hauler,
Recology. The City's "Pay-As-You-Throw" system charges customers by the volume of landfill-bound
materials, which provides a financial incentive to separate recyclables and compostables from other
discards. The City's Department of the Environment's Zero Waste Program has led the City to
achieve 80% diversion, the highest diversion rate in North America.[15]
While waste transport within a given country falls under national regulations, trans-boundary movement of
waste is often subject to international treaties. A major concern to many countries in the world has been
hazardous waste. The Basel Convention, ratified by 172 countries, deprecates movement of hazardous
waste from developed to less developed countries. The provisions of the Basel convention have been
integrated into the EU waste shipment regulation. Nuclear waste, although considered hazardous, does
not fall under the jurisdiction of the Basel Convention.

Technologies[edit]
Traditionally the waste management industry has been slow to adopt new technologies such
as RFID (Radio Frequency Identification) tags, GPS and integrated software packages which enable
better quality data to be collected without the use of estimation or manual data entry.

 Technologies like RFID tags are now being used to collect data on presentation rates for curb-side
pick-ups.
 Benefits of GPS tracking is particularly evident when considering the efficiency of ad hoc pick-ups
(like skip bins or dumpsters) where the collection is done on a consumer request basis.
 Integrated software packages are useful in aggregating this data for use in optimisation of operations
for waste collection operations.
 Rear vision cameras are commonly used for OH&S (Occupational Health & Safety) reasons and
video recording devices are becoming more widely used, particularly concerning residential services.
Waste management concepts[edit]

Diagram of the waste hierarchy.

There are a number of concepts about waste management which vary in their usage between countries
or regions. Some of the most general, widely used concepts include:

 Waste hierarchy - The waste hierarchy refers to the "3 Rs" reduce, reuse and recycle, which classify
waste management strategies according to their desirability in terms of waste minimization. The
 waste hierarchy remains the cornerstone of most waste minimization strategies. The aim of the waste
hierarchy is to extract the maximum practical benefits from products and to generate the minimum
amount of waste see: resource recovery.
 Polluter pays principle - the Polluter Pays Principle is a principle where the polluting party pays for the
impact caused to the environment. With respect to waste management, this generally refers to the
requirement for a waste generator to pay for appropriate disposal of the unrecoverable material.
Scientific journals[edit]
See also: Category:Waste management journals

Related scientific journals in this area include:

 Environmental and Resource Economics

 Environmental Monitoring and Assessment
 Journal of Environmental Assessment Policy and Management
 Journal of Environmental Economics and Management
See also[edit]