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TEXT 5. FIGHTIHG ATMOSPHERIC POLLUTION

Article 12 of the Law of the Conservation of Nature reads: "The content of harmful substances in emissions into the atmosphere, water, and soil shall not exceed maximum permissible concentrations established with due regard tо the economic increases and hygienic standards."

The limits were determined by a study of the influence of atmospheric pollutants on the environment and the conditions of life and health of the population.

Industrial wastes, heating systems are of greater concern in certain cities, areas and individual factories. In such cases, purification plants may be built with different methods of purification (mechanical, chemical, electric and complex). The degree of purification obtained is extremely varied as it depends on the physiochemical properties of the pollutant and the efficiency of the method and equipment. There are rough purification methods which are 70 to 85 per cent effective, medium purification – 95 to 98 per cent and fine purification – over 99 percent. The purification of industrial wastes not only protects the air from pollution but also saves raw materials and provides the enterprise with additional profit. Trapping and recuperation of useful products in smoke emissions have not only sanitary but also national economic importance.

However, a purification plant is not enough in itself. The most promising way to solve the problem of clean air is to improve technology: reduce emissions into the atmosphere and make maximum use of waste. It is cheaper and easier to find a way of eliminating the possibility of waste formation than to build a purification plant which may cost more than the production technology itself. For example, it is very difficult and very costly to purify every hour hundreds of thousands of cubic metres of air containing compounds of lead and mercury. The process requires a purification plant costing more than the enterprise itself. But on the other hand, it is quite possible to design a process whereby the refinement of lead would exclude the possibility of vapour and aerosols being freely discharged into the atmosphere and causing giant streams of air and surrounding territory to be polluted by lead.

A similar situation exists with motor transportation: it is not enough to reduce the noise and soot in exhaust fumes, the design of the engine must be improved, the automobile modernized. Considerable improvements should be introduced into motor transportations operation to reduce air pollution by exhaust fumes and eventually eliminate it completely. The following measures are important to make exhaust fumes less toxic:

1. To introduce improved carburetors, reducing emission of toxic substances.

2. A particularly interesting method to reduce atmospheric pollution would be to switch cars to gaseous fuel (liquefied gas).

3. By adding agents to the fuel it is possible to change the course of oxidation of hydrocarbons, to reduce the formation of some toxic components - carbon monoxide, hydrocarbons, aldehydes, soot and others.

4. Neutralization of exhaust gases by installing neutralіzers. Of all the devices proposed, the best known are flame and catalytic neutralizes.

5. In addition to improving existing automobile engine, a search is being conducted in Ukraine and abroad for fundamentally different power units.

The most promising seems to be the electric automobiles.

The major advantages of the electric automobile are quiet running and absence of exhaust fumes, i.e., protection of the environment.

Improvement in city planning is of great importance in keeping the air clean. Factories are now usually built beyond city limits. Special zones must be established between housing estates and industrial enterprises protecting the population from smoke, gases, dust, noise and unpleasant odours.

Plant life cleans the air in cities of harmful components. Trees play the role of biological filters absorbing gas contaminants from the air while particles of dust settle on their leaves and branches.

TEXT 6. ECOLOGY IS A PRIORITY

The ecological problem, which is also very much a social one, is one of the pressing problems of our days. It is closely linked, through cause and effect relations, to the problems of economic growth, progress in science and technology, natural resources, energy and food supplies. In many cases the environmental problem has become a dominant one in relation to many others.

The pollution of the environment the destruction of ecosystems, the destruction of many species of plants and animals have now reached threatening proportions. An increasing influence on nature and the application of new technological processes (whose consequences are increasingly dangerous for the environment) may cause catastrophic results. Negative anthropogenic influences threaten to disrupt nature's basic cycles and to undermine the self-regenerating capacities of the biosphere and of its individual components.

This is illustrated by the following data. By comparison with the beginning of the twentieth century the accumulation of carbon dioxide in the atmosphere, as well as of aerosols, has increased globally by 20 percent. As a result of the formation of a layer of carbon dioxide around the Earth which encloses it like a glass cover the threat of unfavourable changes in climate has arisen that may transform our blue planet into an enormous greenhouse during the next decades, with possibly catastrophic effects. Those include changes in its energy balance and a gradual increase in temperature that will transform fertile regions into arid ones, raise the level of water in the oceans (through the melting of polar and drifting ice) and produce a flooding of great numbers of coastal lands and cities.

These impede the vital activities and reproductive functions of individuals and cause their genetic degeneration. Calculations of researchers indicate that increases in natural background radiation by only 10 rads may lead to the birth of 6 million hereditary defective persons in each generation. Already now, according to UNO experts 10.5 percent of people are born with hereditary (genetic) defects. Data concerning deaths from cancer published by the National Cancer Institute of the US indicate that 60 percent or more of the cases are caused by various cancer producing factors іn the environment.

Последнее изменение этой страницы: 2016-07-22

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