A.P. Mamet's scientific contributions

Typical for European states, US and Japan approaches to wastes discharge of the water treatment plants (WTP) of thermal power plants (TPP) into surface water reservoirs are considered. It is noted that the problems of the WTP discharge rendering and abolition should solved on a scale of a TPP in a whole with accounting the contribution of a concrete TPP in pollution of water reservoirs of its region. In the first place it is necessary to improve the WTP technological circuits and other water treatment systems at a TPP in direction of lowering the flow rate of chemical reagents and water for obtaining a minimum volume of residual discharges and contained in them salts.

The main principles of designing waste-free water treatment plants for thermal and nuclear electric power stations were discussed. Selection of optimal variants of the plants described was based on using the results of comparative economic analysis. The first principle stated that calcium and magnesium compounds should be removed as completely as possible in the form of practically insoluble or slightly soluble compounds such as calcium carbonate, magnesium hydroxide and calcium sulfate.

A review of foreign and native technical literature, which dwells on the development of water treatment equipment (WTE), is presented. General directions of WTE development are reduced to intensification of working processes, increase in water treatment efficiency, economical efficiency and compactness of apparatuses, reduction of material consumption and labour intensity of manufacture. Increase in the engineering level of WTE depends largely on the used ion-exchange materials, accessories, systems of chemical control.

A considerable part of the waste products from thermal power stations burning fossil fuel consists of the flue gases from steam boilers, at a temperature of about 140-150°C, with deviations of ±20-30°C depending on the conditions under which the fuel is burnt. The main components of the flue gases are nitrogen, carbon dioxide, water vapour and also residual oxygen. Emissions of flue gases into the atmosphere cause pollution and poisoning. There is also thermal pollution of the atmosphere. The building of plant to clean flue gases by removing sulphur and nitrogen oxides is a very complex technical and ecological problem facing the thermal power industry, a practical solution to which involves costs exceeding 50-60% of the cost of building the whole power station. The authors describe certain chemical means of utilizing flue gases, or to be more precise the carbon dioxide present in them, at thermal power stations, taking into account the data given in foreign publications and also certain Soviet developments.

One of the priority directions taken recently by scientific/technical progress in chemical technology has been that of using membranes, enabling substances of very different nature and degree of dispersity to be separated effectively and economically both in liquid and in gaseous media. For water preparation plants at power stations the authors regard the most promising of these processes as reverse osmosis. The main feature of reverse osmosis is that practically no chemical reagents are consumed in treating the water (acids, alkalis, etc. ), if the small reagent consumptions for correcting pH, inhibiting salt deposits and periodic washing of membranes are disregarded.

Tests have been carried out at Rovmo Nuclear Power Station for the first time in the Soviet Union on an electromagnetic filter (EMF) with a capacity of 1000 m**3/h and an effective pressure of 4. 0 MPA under hydrazine treatment conditions. The EMF was installed before the ion-exchange mixed bed filters (MBF) as part of the condensate polishing plant (CPP) and had a capacity of 1000 m**3/h. In practice the load on the CPP varied from 600 to 800 m**3/h; the EMF was filled with carbon steel beads 5-7 mm in diameter. The paper presents data on the operational characteristics of iron removal from the condensate by the electromagnetic and mixed bed filters. A flow diagram of the EMF is given and graphs of the filter hydraulic resistance as a function of the feed current and load are also presented.