Abstract. The object of the study are boilers that burn organic fuel and the recovery boilers (RB) of the combined cycle plant (CCP), which are also working on the products of the combustion of hydrocarbon fuels. The purpose of research is to find technologies that increase efficiency of the thermal power plant (TPP) and technologies that reduce the environmental impact on the environment by burning fossil fuels. The paper deals with the technology of the boilers burning hydrocarbon fuel with condensation of water vapor from the exhaust flue gases. Considered the problems caused by using of this technology. Research shows that the main problem of this technology in the boilers is the lack of reliable methods of calculation of heat exchangers, condensers. Particular attention is paid to the application of this technology in the recovery boilers combined-cycle plants, which are currently gaining increasing use in the generation of electricity from the combustion of gas in power plants. It is shown that the application of technology of condensation of water vapor in RB CCP, the temperature decreases of exhaust gases from 100 to 40 qС, allows increasing the efficiency of the RB with 86.2 % to 99.5 %, i.e. at 12.3 %, and increase the efficiency of the CCP at 2.8 %.

Abstract. The object of the study are substances that are used as a working fluid in systems operating on the basis of an organic Rankine cycle. The purpose of research is to find substances with the best thermodynamic, thermal and environmental properties. Research conducted on the basis of the analysis of thermodynamic and thermal properties of substances from the base "REFPROP" and with the help of numerical simulation of combined-cycle plant utilization triple cycle, where the lower cycle is an organic Rankine cycle. Base "REFPROP" describes and allows to calculate the thermodynamic and thermophysical parameters of most of the main substances used in production processes. On the basis of scientific publications on the use of working fluids in an organic Rankine cycle analysis were selected ozone-friendly lowboiling substances: ammonia, butane, pentane and Freon: R134a, R152a, R236fa and R245fa. For these substances have been identified and tabulated molecular weight, temperature of the triple point, boiling point, at atmospheric pressure, the parameters of the critical point, the value of the derivative of the temperature on the entropy of the saturated vapor line and the potential ozone depletion and global warming. It was also identified and tabulated thermodynamic and thermophysical parameters of the steam and liquid substances in a state of saturation at a temperature of 15 qC. This temperature is adopted as the minimum temperature of heat removal in the Rankine cycle when working on the water. Studies have shown that the best thermodynamic, thermal and environmental properties of the considered substances are pentane, butane and R245fa. For a more thorough analysis based on a gas turbine plant NK-36ST it has developed a mathematical model of combined cycle gas turbine (CCGT) triple cycle, where the lower cycle is an organic Rankine cycle, and is used as the air cooler condenser. Air condenser allows stating material at a temperature below 0 qC. Calculation of the parameters of all substances in the model are based on a base "REFPROP". Numerical investigations on this model showed that the highest net efficiency will be at work on pentane. Butane and R245fa have the same net efficiency, for 0.8% lower than pentane. Ammonia has a net efficiency of 2.5% is lower than pentane. CCP net efficiency strongly depends on the condensation temperature of the substance, as for pentane at lower temperature of condensation at 10 °C it is increased by 1%.a Corresponding

No abstract

Abstract. Issues of improving the efficiency of combined cycle gas turbines (CCGT) recovery type have been presented. Efficiency gas turbine plant reaches values of 45 % due to rise in temperature to a gas turbine to 1700 °C. Modern technologies for improving the cooling gas turbine components and reducing the excess air ratio leads to a further increase of the efficiency by 1-2 %. Based on research conducted at the Tomsk Polytechnic University, it shows that the CCGT efficiency can be increased by 2-3 % in the winter time due to the use of organic Rankine cycle, low-boiling substances, and air-cooled condensers (ACC). It is necessary to apply the waste heat recovery with condensation of water vapor from the flue gas, it will enhance the efficiency of the CCGT by 2-3 % to increase the efficiency of the heat recovery steam boiler (HRSB) to 10-12 %. Replacing electric pumps gas turbine engine (GTE) helps to reduce electricity consumption for auxiliary needs CCGT by 0.5-1.5 %. At the same time the heat of flue gas turbine engine may be useful used in HRSB, thus will increase the capacity and efficiency of the steam turbine.

Abstract. The object of the study are low-boiling substances, which can be used as working fluid in the Organic Rankine cycle (ORC) combine cycle gas turbine (CCGT) trinary type. Purpose of research is search for substances with the best thermodynamic, thermophysical and ecological properties. The calculation algorithm represents a mathematical calculation of CCGT in which the lower cycle, operating on low-boiling fluid and utilizes low-potential heat, as an air-cooling device On the basis of available scientific and practical facts on the use of working fluids the organic Rankine cycle for analysis were selected ozone-safe refrigerant: butane, pentane, R236ea, R236fa, R123, R245ca, R245fа, R365mfc, RC318. For these substances were found and tabulated critical pressure and temperature, condensation pressure, density and dynamic viscosity at a given condensation temperature. Studies have shown that the highest thermal net efficiency is achieved when using natural Freon pentane and synthetic R365mfc. Net efficiency CCGT strongly depends on the condensation temperature of the substance. For example, when using pentane when the condensation temperature decreases on 10 С net efficiency increases about 0.71 %.