Putrescible waste

Refrigerated storage facilities or other preservation methods are necessary for putrescible waste. 

Many laboratories do not have an on-site incinerator for radioactive-biological waste. Communities tend to oppose waste incinerators, and on-site incineration is prohibitively costly for some radioactive-biological waste generators. Even institutions that have incinerators must usually rely on off-site disposal for some of their radioactive waste. For radioactive putrescible waste, off-site disposal requires special packaging, storage, and transport considerations. 

In terms of composition, earthquake waste is predominantly construction and demolition waste, that is, waste generated from the demolition of earthquake-affected structures and infrastructure. Waste materials may include metal, concrete, brick, timber, plasterboard, pipes, asphalt, etc. In some cases, where buildings collapse during the earthquake or where buildings are not safe to enter following the earthquake, the waste will include the contents of the building. This could include personal property (e.g., essential documents, money, mobile phones), carpet, furniture, electronic and electrical equipment, plastics, paper, whiteware, putrescible waste, and potentially hazardous materials stored on site (e.g., gas cylinders, oils, pesticides). The exact composition of this waste will depend on the type of building construction and nature of the earthquake impacts. 

Food wastes. Food wastes are the animal, fruit, or vegetable residues (also called garbage) resulting from the handhug, preparation, cooking, and eating of foods. The most important charac teristic of these wastes is that they are putrescible and will decompose rapidly, especially in warm weather. 

Rubbish. Rubbish consists of combustible and noncorn-bustible sohd wastes, excluding food wastes or other putrescible materials. Typically, combustible rubbish consists of materials such as paper, cardboard, plastics, textiles, rubber, leather, wood, furniture, and garden trimmings. Noncombustible rubbish consists of items such as glass, crockeiy, tin cans, aluminum cans, ferrous and other nonferrous metals, dirt, and construction wastes. 

They are suitable to infeed plastics, shredded paper, organics/putrescibles, and glass, but they are not suitable for scrap and mixed-waste containing textiles and plastic film, as the two last components are expected to cause immediate blockages by binding around screws. 

The pneumatic conveyors are suitable for refuse-derived fuel, dense and light plastics, granulated paper, milled glass, and chip wood/timber. They are not suitable for mixed municipal solid waste due to the variable characteristics of the components, organics/putrescibles due to odors, and material deposition in the rotary valves, and metal objects, except shredded aluminum. 

The typical composition of municipal solid waste (MSW) from the UK, an Asian city and a Middle East city is shown in Table 7, and shows that for the UK, a large proportion of the waste is biodegradable. Assuming that the unsorted fines are biodegradable, then the total proportion of waste that is biodegradable is equivalent to 65.8% (this includes paper, putrescibles, unsorted fines, garden waste, textiles and wood). 

Disposal is most difficult for the very small amount of chemical-biological waste that is EPA-regulated as chemically hazardous or contains a chemical, such as lead, that is inappropriate for an animal or medical waste incinerator. Disposal of tissue specimens preserved in ethanol or another flammable solvent is also difficult. In most cases, storage of this waste is limited to 90 days and must be managed at an EPA-permitted chemical waste facility. However, few chemical waste facilities are prepared to handle waste that is putrescible, infectious, or biohazardous. 

Laboratories that have an on-site radioactive waste incinerator have a great advantage in their ability to manage radioactive-biological waste. On-site incineration of radioactive-biological waste is practical and can be done with minimal impact to health or the environment. For waste that is putrescible or may be infectious, on-site incineration is ideal. 

Autoclaving of infectious animal carcasses is difficult because of the waste s high heat capacity and poor heat conductivity, and often unproductive because treated waste remains putrescible. 

Disposing of plastics by burial in sanitary landfill, contrary to popular belief, is by far the safest method of dealing with waste plastics, since, due to the absence of oxygen, they do not oxidise or biodegrade under these conditions. Properly stabilised PVC is stable almost indefinitely in anaerobic landfill and the chlorine will remain locked away without harm to the environment almost indefinitely. The main problem here is the shortage of landfill sites in many of the developed countries. However, in contrast to the behaviour of putrescible materials, plastics do not cause subsequent subsidence and the land can be re-used. 

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