Work in pairs or small groups. Discuss the following issues, then report the general idea of the group to the class.
1) Intensive industrialization threatens nature. It’s a major problem of modern civilization.
2) Is industrial ecology focusing on integrating industrial system into natural systems or is it primarily attempting to emulate ecological systems?
3) Some authors believe that changing industrial systems will also require changes in human behavior and social patterns. What balance between behavioral changes and technological changes is appropriate?
4) The ecological situation in Russia is worsening from year to year, isn’t it? What should be done to stop the process?
5) Our seas and rivers are in danger. They are filled with industrial and nuclear waste, chemical fertilizers and pesticides. What is done in our region to prevent the pollution of the Volga?
UNIT VI. RECYCLING
Work in pairs and speak on the questions. Agree or disagree with your partner.
1) Can you give the definition of the notion «recycling»?
2) What materials can be recycled? Why is it necessary?
3) Are there any disadvantages of this process?
2. Work in pairs and discuss which of the materials are necessary / profitable to recycle:aluminum, ceramics, plastics, glass, textile, steel, paper, chemicals, wood, nuclear waste.
Put the item in the order of their importance.
Read Text A and check if the author of the text thinks the same.
Text A. TYPES OF MATERIALS RECYCLED
Materials ranging from precious metals to broken glass, from old newspapers to plastic spoons, can be recycled. The recycling process reclaims the original material and uses it in new products.
Recycling can be done internally (within a company) or externally (after a product is sold and used). Since the recovered material never left the manufacturing plant, the final product is said to contain preconsumer waste. External recycling occurs when materials used by the customer are returned for processing into new products. Materials ready to be recycled in this manner, such as empty beverage containers, are called postconsumer waste.
Just about any material can be recycled. On an industrial scale, the most commonly recycled materials are those that are used in large quantities.
Steel. There are two methods of making steel using recycled material: the basic oxygen furnace (BOF) method and the electric arc furnace (EAF) method. The BOF method involves mixing molten scrap steel in a furnace with new steel. Steel made by the BOF method typically is used to make sheet-steel products like cans, automobiles, and appliances. The EAF means that scrap steel is placed in a furnace and melted by electricity that arcs between two carbon electrodes. Limestone and other materials are added to the molten steel to remove impurities. Steel produced by the EAF method usually is formed into beams, reinforcing bars, and thick plate.
Aluminum. Recycling aluminum provides a stable, domestic aluminum supply. Aluminum cans almost always produce a profit in community recycling programs. Cans brought to collection centers are crushed, baled, and shipped to regional mills or reclamation plants. The cans are then shredded to reduce volume and heated to remove coatings and moisture. Next, they are put into a furnace, melted, and formed into ingots, or bars. The ingots go to another mill to be rolled into sheets. The sheets are sent to a container plant and cut into disks from which new cans are formed.
Plastics. Plastics are more difficult to recycle than metal, paper, or glass. One problem is that any of seven categories of plastics can be used for containers alone. For effective recycling, the different types cannot be mixed. The recycling process for plastic normally involves cleaning it, shredding it into flakes, then melting the flakes into pellets. The pellets are melted into a final product.
Paper and Paper Products. Paper products that include cardboard containers, wrapping paper, office paper and newsprintcan be recycled.
In newspaper recycling, old newspapers are collected and searched for contaminants such as plastic bags and aluminum foil. The paper goes to a processing plant where it is mixed with hot water and turned into pulp in a machine that works much like a big kitchen blender. The pulp then goes to a large vat where the ink separates from the paper fibers and floats to the surface. The ink is skimmed off, dried and reused as ink or burned as boiler fuel. The cleaned pulp is mixed with new wood fibers to be made into paper again.
Glass. Scrap glass taken from the glass manufacturing process, called cullet, has been internally recycled for years. The scrap glass is economical to use as a raw material because it melts at lower temperatures than other raw materials, thus saving fuel and operating costs.
Glass that is to be recycled must be relatively free from impurities and sorted by color. Glass containers are the most commonly recycled form of glass, and their colors are flint (clear), amber (brown), and green. The recycled glass is melted in a furnace and formed into new products.
Chemicals and Hazardous Waste. Household hazardous wastes include drain cleaners, oven cleaners, window cleaners, disinfectants, motor oil, paints, paint thinners, and pesticides. Most municipalities ban hazardous waste from the regular trash. Periodically, citizens are alerted that they can take their hazardous waste to a collection point where trained workers sort it, recycle what they can, and package the remainder in special leak-proof containers called lab packs, for safe disposal. Typical materials recycled from the collection drives are motor oil, paint, antifreeze, and tires. Business and industry have made much progress in reducing both the hazardous waste they generate and its toxicity.
Nuclear Waste. Certain types of nuclear waste can be recycled, while other types are considered too dangerous to recycle. Low-level wastes include radioactive material from research activities, medical wastes, and contaminated machinery from nuclear reactors. Nickel is the major metal of construction in the nuclear power field and much of it is recycled after surface contamination has been removed.
High-level wastes come from the reprocessing of spent fuel and from the processing of nuclear weapons. These wastes emit gamma radiation, which can cause birth defects, disease, and death. High-level nuclear waste is so toxic it is not normally recycled. Instead, it is fused into inert glass tubes encased in stainless steel cylinders, which are then stored underground.
Tick the sentence that best describes the results of Recycling.
a) In general, using recycled materials to make new products costs more and requires more energy than using new materials.
b) Recycling increases the amount of land needed for trash dumps by reducing the volume of discarded waste.
c) Recycling can reduce pollution, either by reducing the demand for high-pollution alternatives or by minimizing the amount of pollution produced during the manufacturing process.
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