Fighting atmospheric pollution

Article 12 of the Law on 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 to all economic interest and hygienic standards”. The Soviet Union was the first country in the world to legislatively establish maximum allowable concentrations (MAC) of atmospheric pollutants. The limits were determined by a study on the influence of atmospheric pollutants on the environment and the conditions of life and health of the pollution.

Industrial wastes, not 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 physicochemical properties of the pollutants 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 per cent. 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 recuperationof 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 vapours 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 transportation 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 atmosphere pollution would be to switch cars to gaseous fuel (liquefied gas).

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

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

5. In addition to improving existing automobile engine, a search is being conducted in the USSR and abroad for fundamentally different power units. The most promising seems to be electric automobiles.

The major advantages of the electric automobile are quite 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.

Date: 2015-09-02; view: 415; Нарушение авторских прав