ESTIMATION OF REDUCTION OF NITROGEN OXIDES IN COMBINED STEAM AND GAS POWER PLANTS

Abstract

The characteristic of the united power system of Ukraine, based on thermal, nuclear and hydro power plants, as well as on alternative and renewable sources, is carried out. The structure of power system potential indicates a lack of maneuver capacity, some plants are of low mobility. Thermal power is in critical condition due to expired service time of the main technological equipment, additionally, it is a huge source of emissions of harmful substances into the environment. An attempt to use them to cover peak loads only worsens their critical state.It is suggested to restore thermal power on the basis of combined steam and gas power plants. Moreover, for operation of gas section it is necessary to use working substance, which is formed in an additional furnace by heating the compressed air with heat from combustion of some part of coal flow, which subsequently enters the main furnace. The steam and gas generation branches are parallel connected, which extends the range of power change (increasing its maneuverability.) Gas generation increases mobility (rate of power change). For combustion of organic fuel, oxygen enriched atmospheric air is fed, and a nitrogen-based fraction can form a working substance for gas generation. With such an organization of combustion the coefficient of excess air can be ignored, which enables to reduce the volume of flue gases. The membrane separation of atmospheric air into fractions - one en-riched with oxygen, and another with nitrogen, improves the environmentalperformance of a power plant, while increasing its power and economic indices. On the example of the boiler unit TP-92 the basic parameters of a power plant are checked by a calculation method. It is confirmed that the proposed technical solutions point to the correctness and validity of the assumptions. Analysis of the existing technical level of scientific research increases confidence in perspective of the selected direction.