Recycling community

Generally, recyclables are either coUected at curbside or deposited by consumers at various types of drop-off locations, such as local recycling centers, community service clubs, dealers, and commercial buyback centers. Curbside coUections of recyclables can be accompUshed either in conjunction with the pickup of aU MSW or as a separate activity. Co-coUection systems range from complete commingling of aU waste for later separation at a mixed waste processing facility to transporting essentially source-separated recyclables in the same tmck as MSW. 

Recycling is not the total answer to the soUd waste problem. However, efficiently operated recycling programs can easily divert 35% or more of municipal soUd waste away from disposal. Curbside coUection systems offer the opportunity to coUect the greatest amount of recyclables in the most cost-efficient manner. It is imperative that communities and recyclers operate programs that are glass-friendly and which result in color-separated, contaminant-free material. 

Tires. As with MSW disposal, state and local communities have sought increased utiUty assistance in waste tire management. In the United States, scrap tires are generated at the rate of one tire per person per year, and only 20% are reused or recycled in some fashion. Stockpiles exceed 2 x 10 scrap tires (see Recycling, rubber). 

Vinyl is recycled by at least 170 recyclers in the United States and Canada. In 1994, about 2.9 x 10 t (6.5 x 10 lb) of post-consumer vinyl were recycled in the United States. An estimated additional 135 x 10 t (300 x 10 lb) of vinyl post-industdal scrap was diverted from landfills and recycled into second-generation products. More than 3500 communities accept vinyl products in their recycling programs, which is about 25% of all communities that recycle. 

Water purification and recycling is now a major industry.The method of treatment depends on the source of the water, the use envisaged and the volume required. Luckily the human body is very tolerant to changes in the composition of drinking water, and in many communities this may contain 0.5 gl or more of dissolved solids (Table 14.7). Prior treatment may consist of coagulation (by addition of alum or chlorinated FeS04 to produce floes of Al(OH)3 or Fe(OH)3), filtration, softening (removal of... 

Another contaminant of concern for the Delta is Se. Selenium occurs in high concentrations in the soils of the western San Joaquin Valley associated with salts that have accumulated in this region [10]. Selenium is recycled through agricultural retom flows to the river and transported to the Delta and San Francisco Bay. The Se is transformed into a more bioavailable form by microbial communities and aquatic plants. The Se is passed through the foodweb with particular concern for bottomfeeding migratory waterfowl and predatory fishes. The hydrodynamics of water from the San Joaquin River is an important consideration in the intensity and distribution of Se contamination within the Delta. 

Chandrasekhar, S., Narsihmulu, C., Sultana, S.S., Reddy, N.R. (2003) Osmium Tetrox-ide in Poly(ethylene glycol) (PEG) A Recyclable Reaction Medium for Rapid Asymmetric Dihydroxylation Under Sharpless Conditions. Chemical Communications, 1716-1717. 

Stevens, P.D., Li, G.F., Fan, J.D., Yen, M. and Gao, Y. (2005) Recycling of homogeneous Pd catalysts using superparamagnetic nanoparticles as novel soluble supports for Suzuki, Heck, and Sonogashira cross-coupling reactions. Chemical Communications (35), 4435-4437. 

Yoon, H., Ko, S. and Jang, J. (2007) Nitrogen-doped magnetic carbon nanoparticles as catalyst supports for efficient recovery and recycling. Chemical Communications (14), 1468-1470. 

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