Lillian Liem 6S 26 Date: 19-01-2004
|
|  Yüklə 27.5 Kb.
|
| Lillian Liem 6S 26
Date:19-01-2004 Discuss on the recycling of wastes e.g. paper and aluminium Recycling is an important aspect in conservation. The term recycling has two dimensions: recovery and utilization. Recovery refers to the collection of waster material that can be reused. Utilization refers to the processing of diverted waste into new and useful material and products. Some of the solid wastes can be recycled. They can be classified under the categories of reusable material and recyclable materials. Renewable material (such as glass bottles) can be sold to relevant manufactures. Recyclable materials include paper, metals (such as aluninium cans), certain types of plastics, types and other valuable materials. They are separated and then sold as raw materials for recycling. Glass, steel (or "tin") and aluminum are easy to recognize and recycle. For clarity, a recycling symbol should be present, but most people have little trouble sorting these materials. Glass bottles must not be mixed with other types of glass such as windows, light bulbs, mirrors, glass tableware, Pyrex or auto glass. Ceramics contaminate glass and are difficult to sort out. Clear glass is the most valuable. Mixed color glass is near worthless, and broken glass is hard to sort. There have been marketing experiments with plastic and steel cans that look exactly like aluminum cans. Recycling plants have been damaged by these fakes. The distinctive shape of an aluminum beverage can must be reserved for aluminum beverage cans only. It is no longer necessary to remove labels for recycling. To save water, clean only enough to prevent odors. Unlike with plastics, the high temperature of glass and metal processing deals easily with contamination. Scrap aluminum is accepted in many places. Other metals are rarely accepted. Most types of paper can be recycled. Newspapers have been recycled profitably for decades, and recycling of other paper is growing. Virgin paper pulp prices have soared in recent years prompting construction of more plants capable of using waste paper. They key to recycling is collecting large quantities of clean, well-sorted, uncontaminated and dry paper. Paper that can't be recycled as normal "mixed paper" includes: food contaminated paper, waxed paper, waxed cardboard milk & juice containers, oil soaked paper, carbon paper, sanitary products or tissues, thermal fax paper, stickers and plastic laminated paper such as fast food wrappers, juice boxes, and pet food bags. With a little bit of care much plastic can be recycled, and collection of plastics for recycling is increasing rapidly. Plastic recycling faces one huge problem: plastic types must not be mixed for recycling, yet it is impossible to tell one type from another by sight or touch. All plastic containers we purchase should be marked with a large and clear recycling code. This code must be molded into the plastic and located on the bottom surface of the container. Ideally the entire container should be made of the same plastic to avoid confusion, but often the caps are of a different type. Caps should be separately marked, but few are. Note that most caps are not of the same type as the bottle they sit on Recycling of waste materials helps to alleviate solid waste pollution to the environment. Reducing the rate of depletion of natural resources thus saving the energy used in mining and processing of natural resources. Less wastes, less the needs for landfill sites. Development of recycling industry can create more posts. Also, educating people through, the practice of recycling, about the important of proper waste disposal, thrift use of natural resources and environmental problems. |