Resource recovery

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Resource recovery is the selective extraction of disposed materials for a specific next use, such as recycling, composting or energy generation in order to extract the maximum benefits from products, delay the consumption of virgin resources, and reduce the amount of waste generated. Resource recovery differs from the management of waste by using life-cycle analysis (LCA) to offer alternatives to landfill disposal of discarded materials. A number of studies on municipal solid waste (MSW) 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 waste fraction via anaerobic digestion to be the favoured alternatives to landfill disposal.

Similarly, in the context of sanitation, the term "resource recovery" is used to denote sanitation systems that aim to recover and reuse the resources that are contained in wastewater and excreta (urine and feces). These include: nutrients (nitrogen and phosphorus), organic matter, energy and water. This concept is also referred to as ecological sanitation or productive sanitation.

Recycling of solid waste[edit]

Main article: Recycling
Steel crushed and baled for recycling

Recycling is a resource recovery practice that refers to the collection and reuse of disposed 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, or sorted directly from mixed waste streams.

The most common consumer products recycled include aluminium such as beverage cans, copper such as wire, steel 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 recycling material accepted varies by city and country. Each city and country have different recycling programs in place that can handle the various types of recyclable materials.

Organic matter[edit]

An active compost heap.

Disposed materials that are organic in nature, such as plant material, food scraps, and paper products, can be recycled using biological 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 is to control and accelerate the natural process of decomposition of organic matter.

There is a large variety of composting and digestion methods and technologies varying in complexity from simple home compost heaps, to small town scale batch digesters, industrial-scale enclosed-vessel digestion of mixed domestic waste (see mechanical biological treatment). Methods of biological decomposition are differentiated as being aerobic or anaerobic methods, though hybrids of the two methods also exist.

Anaerobic digestion of the organic fraction of municipal solid waste (MSW) has been found to be in a number of LCA analysis studies[1][2] to be more environmentally effective, than landfill, incineration or pyrolysis. The resulting biogas (methane) though must be used for cogeneration (electricity and heat preferably on or close to the site of production) and can be used with a little upgrading in gas combustion engines or turbines. With further upgrading to synthetic natural gas it can be injected into the natural gas network or further refined to hydrogen for use in stationary cogeneration fuel cells. Its use in fuel cells eliminates the pollution from products of combustion. There is a large variety of composting and digestion methods and technologies varying in complexity from simple home compost heaps, to small town scale batch digesters, industrial-scale, enclosed-vessel digestion of mixed domestic waste (see mechanical biological treatment). Methods of biological decomposition are differentiated as being aerobic or anaerobic methods, though hybrids of the two methods also exist.

Recovery methods[edit]

In Australia, source-separated curbside collection is one method of resource recovery. Every urban domestic household is provided with three bins—one for recycling, another for general waste, and another for garden materials, this bin is provided by the municipality if requested. Also, many households have compost bins; but this is not provided by the municipality. To encourage recycling, municipalities provide large recycle bins, which are larger than general waste bins.

Municipal, commercial and industrial, construction and demolition debris is dumped at landfills and some is recycled. Household disposal materials are segregated: recyclables sorted and made into new products, and unusable material is dumped in landfill areas. According to the Australian Bureau of Statistics (ABS), the recycling rate is high and is "increasing, with 99% of households reporting that they had recycled or reused within the past year (2003 survey), up from 85% in 1992". This suggests that Australians are in favour of reduced or no landfilling and the recovery of materials through recycling. In 2002–03 "30% of materials from municipalities, 45% from commercial and industrial generators and 57% from construction and demolition debris" was recycled. Energy is produced is part of resource recovery as well: some landfill gas is captured for fuel or electricity generation, although this is considered the last resort, as the point of resource recovery is avoidance of landfill disposal altogether.

Sustainability[edit]

Resource recovery is a key component in a business' ability to maintaining ISO14001 accreditation. Companies are encouraged to improve their environmental efficiencies each year. One way to do this is by changing a company from a system of managing wastes to a resource recovery system (such as recycling: glass, food waste, paper and cardboard, plastic bottles etc.)

Education and awareness in the area of resource recovery is increasingly important from a global perspective of resource management. The Talloires Declaration is a declaration for sustainability concerned about the unprecedented scale and speed of environmental pollution and degradation, and the depletion of natural resources. Local, regional, and global air pollution; accumulation and distribution of toxic wastes; destruction and depletion of forests, soil, and water; depletion of the ozone layer and emission of "green house" gases threaten the survival of humans and thousands of other living species, the integrity of the earth and its biodiversity, the security of nations, and the heritage of future generations. Several universities have implemented the Talloires Declaration by establishing environmental management and resource recovery programs. University and vocational education are promoted by various organizations, e.g., WAMITAB and Chartered Institution of Wastes Management. Many supermarkets encourage customers to use their reverse vending machines to deposit used purchased containers and receive a refund from the recycling fees. Brands that manufacture such machines include Tomra and Envipco.

In 2010, CNBC aired the documentary Trash Inc: The Secret Life of Garbage about waste, what happens to it when it's "thrown away", and its impact on the world.[3]

Extended producer responsibility[edit]

Extended producer responsibility (EPR) is a strategy designed to promote the integration of all costs associated with products throughout their life cycle (including end-of-life disposal costs) into the market price of the product. Extended producer responsibility is meant to impose accountability over the entire lifecycle of products and packaging introduced to the market. This means that firms which manufacture, import and/or sell products are required to be responsible for the products after their useful life as well as during manufacture.

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