Municipal waste, packaging materials

PE represents the largest constituent of plastics in the municipal waste stream and the fraction is mainly composed of high-density polyethylene (HDPE) packaging materials. Recycling this type of waste packaging material yields a stream of recycled plastic that is highly homogeneous and consistent [8]. 

Confusion as to what constitutes municipal waste is presenting an obstacle to the use of packaging waste as a fuel in cement kilns. Whilst cement kilns can bum hazardous waste, they cannot bum a wide range of non-hazardous materials, it is reported. The case of Castle Cement is described which planned to bum a range of non-hazardous commercial and industrial wastes. Some waste-fired combustion processes, however, such as UK Waste s Fibre Fuel operation have been granted derogations where fuel is manufactured by advanced mechanical processes, which includes the production of fuel pellets. This latter process would be pointless for the cement industry since their fuels have to be pulverised. The problems are further discussed with reference to current European legislation. 

United States alone, 5 x 109 kg of plastic resins (typically used in packaging and transportation) are produced every year. Disposable goods and packing material represent about one-third of the total plastic production and have the largest environmental impact. More than 90% of the plastic material in municipal waste consists of polyethylene, polyvinyl chloride, and polystyrene, which are all resistant to biodegradation (see Table 9.1). 

Plastics have become the material of choice in the modem world and their applications in the industrial field are continually increasing. Presently plastics are manufactured for various uses such as consumer packaging, wires, pipes, containers, bottles, appliances, electrical/electronic parts, compnters and automotive parts. Most post-consumer plastic products are discarded and end up as mixed plastic municipal waste. The disposal of this waste has become a major social concern. 

The same desirable characteristics that make polymers popular materials for consumer products— durability, strength, and lack of reactivity— also contribute to environmental problems. Polymers do not degrade readily, and as a result, billions of pounds of polymers end up in landfills every year. Estimates suggest that synthetic polymers comprise 11% of solid municipal waste, 30% of which comes from packaging materials. 

H. Alter The Origins of Municipal Solid Waste The Relations between Residues from Packaging Materials and Food. In Waste Management and Research, Vol. 1, pp 103-114 (1989). 

Municipal solid waste (MSW) Is a highly variable "raw material," by both season and location. However, It Is generally accepted to have a composition within the ranges shown In Table I (D. Celluloslc materials. Including paper, newsprint, packaging materials, wood wastes, and yard clippings, constitute over 50% of MSW. 

There is no doubt that for the municipal collection of organic waste biodegradable bags should be recommended. From an ecological point of view the Mater-Bi bag has to be given preference over the other compostable bag (paper bag "haushalt kompost"). Short routes of transport and minimal use of packaging material should be weighty criteria as for the choice of product. 

Alter H. The origins of municipal solid waste the relations between residues from packaging materials and food. Waste Manag Res 1989 7 (2) 103-114. 

It has been estimated by the U.S. EPA (1990b] that 29 billion pounds of plasdc are disposed in the MSW stream each year and that only 1.1% of the waste plastic stream, or 400 million pounds annually, ate recovered (Table 1.4). Municipal solid wastes come from residential, commercial, institutional and industrial sources, but do not include wastes such as construction debris, household hazardous waste, or other wastes regulated by Resource Conservation and Recovery Act Subtitle D. Seventy percent of discarded plastic is composed of nondurable goods and packaging materials. 

Summers, J., Mikofalvy, B., and Little, S. Use of X-Ray Fluorescence for Soning Vinyl from Other Packaging Materials in Municipal Solid Waste. Journal of Vinvl Technology 12(3) 161-164, 1990a. 

Recently, compostable packaging materials were introduced into the market to reduce the amounts of conventional packaging materials and at the same time be recovered by the municipal organic waste collection system. An example of commercial implementation of compostable polymers includes Cargill Dow Nature Works polylactic acid (PLA), which is produced at a rate of 140000 tonnes/year at Blair, Nebraska (USA), via carbohydrate fermentation. Other... 

In the first place why do we feel that we must recycle plastics Is this because we want to conserve our natural resources, in this case oil or coal, for future generations Or are we concerned about the environmental problems which are caused by plastics waste Certainly plastics represent a dominant component among packaging materials, some 40% according to a recent survey, and being durable thus represent a major part of municipal solid waste. This easily draws them to the attention of the general public. 

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