Recycling

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Recycling industrial waste

Although many government programs concentrate on recycling at home, 64% of waste in the United Kingdom is generated by industry. The focus of many recycling programs in industry is their cost-effectiveness. The ubiquitous nature of cardboard packaging makes cardboard a commonly waste product recycled by companies that deal heavily in packaged goods, such as retail stores, warehouses, and goods distributors. Other industries deal in niche and specialized products, depending on the waste materials they handle.

Glass, lumber, wood pulp and paper manufacturers all deal directly in commonly recycled materials; however, independent tire dealers may collect and recycle rubber tires for a profit.

The waste produced from burning coal in a Coal-fired power station is often called fly ash in the United States or fuel ash elsewhere. It is a very useful material and used in concrete construction. It exhibits Pozzolanic activity.

Levels of metals recycling are generally low. In 2010, the International Resource Panel, hosted by the United Nations Environment Programme (UNEP), published reports on metal stocks and their recycling rates. It reported that the increase in the use of metals during the 20th and into the 21st century has led to a substantial shift in metal stocks from below-ground to use in above-ground applications within society. For example, in the US, in-use copper grew from 73 to 238 kg per capita between 1932–1999.

The report’s authors observed that, as metals are inherently recyclable, metal stocks in society can serve as huge above-ground mines (the term “urban mining” has thus been coined). However, they found that the recycling rates of many metals are low. They warned that the recycling rates of some rare metals used in applications such as mobile phones, battery packs for hybrid cars and fuel cells, are so low that unless future end-of-life recycling rates are dramatically increased, these critical metals will become unavailable for use in modern technology.

The military recycles some metals. The U.S. Navy’s Ship Disposal Program uses ship breaking to reclaim the steel of old vessels. Ships may also be sunk to create artificial reefs. Uranium is a dense metal that has qualities superior to lead and titanium for many military and industrial uses. Uranium left over from processing it into nuclear weapons and fuel for nuclear reactors is called depleted uranium, and is used by all branches of the U.S. military for the development of such things as armor-piercing shells and shielding.

The construction industry may recycle concrete and old road surface pavement, selling these materials for profit.

Some rapidly growing industries, particularly the renewable energy and solar photovoltaic technology industries, are proactively creating recycling policies even before their waste streams have considerable volume, anticipating future demand.

Recycling of plastics is more difficult, as most programs are not able to reach the necessary level of quality. Recycling of PVC often results in downcycling of the material, which means only products of lower quality standard can be made with the recycled material.

E-waste is a growing problem, accounting for 20–50 million metric tons of global waste per year according to the EPA. It is also the fastest growing waste stream in the EU. Many recyclers do not recycle e-waste responsibly. After the cargo barge Khian Sea dumped 14,000 metric tons of toxic ash in Haiti, the Basel Convention was formed to stem the flow of hazardous substances into poorer countries. They created the e-Stewards certification to ensure that recyclers are held to the highest standards for environmental responsibility and to help consumers identify responsible recyclers. It operates alongside other prominent legislation, such as the Waste Electrical and Electronic Equipment Directive of the EU and the United States National Computer Recycling Act, to prevent poisonous chemicals from entering waterways and the atmosphere.

In the recycling process, television sets, monitors, cell phones, and computers are typically tested for reuse and repaired. If broken, they may be disassembled for parts still having high value if labor is cheap enough. Other e-waste is shredded to pieces roughly 10 centimetres (3.9 in) in size and manually checked to separate toxic batteries and capacitors, which contain poisonous metals. The remaining pieces are further shredded to 10 millimetres (0.39 in) particles and passed under a magnet to remove ferrous metals. An eddy current ejects non-ferrous metals, which are sorted by density either by a centrifuge or vibrating plates. Precious metals can be dissolved in acid, sorted, and smelted into ingots. The remaining glass and plastic fractions are separated by density and sold to re-processors. Television sets and monitors must be manually disassembled to remove lead from CRTs and the mercury backlight from LCDs.

Vehicles, solar panels and wind turbines can also be recycled. They often contain rare-earth elements (REE) and/or other critical raw materials. For electric car production, large amounts of REE’s are typically required.

Whereas many critical raw elements and REE’s can be recovered, environmental engineer Phillipe Bihouix reports that recycling of indium, gallium, germanium, selenium, and tantalum is still very difficult and their recycling rates are very low.

Plastic recycling

Plastic recycling is the process of recovering scrap or waste plastic and reprocessing the material into useful products, sometimes completely different in form from their original state. For instance, this could mean melting down soft drink bottles and then casting them as plastic chairs and tables. For some types of plastic, the same piece of plastic can only be recycled about 2–3 times before its quality decreases to the point where it can no longer be used.

#United Nations Environment Programme

#Plastic recycling

#industry recycle

#ISBC