Decreasing the Weight-Size Parameters of Gas-Steam Turbine Plant by Increasing the Efficiency of Thermodynamic Processes in the Condenser

The aim of this work is decreasing the weight-size parameters of the contact gas-steam turbine plant and contact condenser elements by increasing the efficiency of thermal-gas dynamic processes of condensation through rational irrigation of countercurrent gas-steam flow. To achieve the goal the total efficiency of water-return drops ranging from 0.1 to 1 mm at different initial velocities from 5 to 35 m/s emitted by the multi-nozzle sprinkler was determined by mathematical modeling of the liquid droplet movement processes, heat and mass transfer between the liquid droplet and gas-vapor mixture, and gas-vapor mixture pressure loss. The effect of increasing the gas-steam mixture velocity from 3.3 to 6 m/s on the overall efficiency of water return was determined. The novelty of the obtained results was defined by an increase in the water return into cycle from 12 to 13% with a droplet diameter of 0.3 -- 0.4 mm and the initial velocity from the sprinkler of 5--10 m/s. The velocity of the mixture was to 6 m/s at rational correlations of the initial velocity of the droplets’ escape, which increased the total amount of heat withdrawn to 11%. The positive effect conditions of irrigation processes on thermogasdynamic and weight-size parameters of the condenser elements for the contact gas and steam turbine plant at full pressure recovery coefficients of over 0.967 were substantiated. The most significant result was the reduction of the weight-size parameters of the marine infrastructure object power plant from 8 to 19%.

Exploitation of Empty Palm Fruit Bunch for the Generation of Electricity

Electricity is very important for the growth and economy of a country. Biomass wastes such as waste from oil palm plantation companies can be harnessed for this purpose since they are usually abundant in nature. The aim of this study is to evaluate the utilization of empty palm fruit bunch for the generation of electricity. The empty fruit bunch (EFB) was used in firing a steam turbine plant (boiler) for the generation of electricity. The power plant that was used in this research is owned by PRESCO Nigeria Limited located in Ikpoba-Okha local government area of Edo state. 1.7 MW of electricity was generated by burning empty fruit bunch (EFB) at a rate of 896 kg/h when the steam boiler was used. This value was compared with the traditional power plant fired using methane gas which produces 4.5MW. This value (1.7 MW) shows that EFB is a very good alternative for firing a boiler plant, power generation and elimination of wastes.

The potential for reducing TPP water consumption through the use of heat pumps

Largest part of consumed water resources in Russian Federation is related to energy sector; accordingly, we need to develop measures to ensure their rational use. This paper analyzes the potential for reducing water consumption of thermal power plants by applying heat pumps in the condenser cooling system of a steam turbine plant. The calculations were performed for two CCGT-450 power units with three main options for technical water supply systems. The greatest environmental and economic effects are provided by the use of heat pumps at TPPs with a once-through water supply system. Utilization of all low-grade heat of the condenser cooling system of a steam turbine plant is irrational due to an increase in energy consumption for TPP own needs. With a further growth of tax rates for water intake from surface water bodies, positive effect of application of heat pumps in the condenser cooling system of a steam turbine plant will increase by an order of magnitude.

Application of Steam Jet Injector for Latent Heat Recovery of Marine Steam Turbine Propulsion Plant

This paper presents the results of previously carried out analyses regarding efficiency and criteria evaluation of various propulsion plants of modern LNG (Liquid Natural Gas) carriers. The results of previous identification and quality assessment of waste heat energy sources of a CST (Conventional Steam Turbine) plant are presente. In this paper the possibility of use a steam jet injector in order to recover the latent heat is analysed. Calculations were carried out for an injector equipped with a de Laval nozzle, determining the thermodynamic state parameters of the mixture of drive steam and sucked in steam as well as the steam on the outlet of the injector for the various ejection ratios. On the basis of the results of the injector calculation, the heat balance of a simple regenerative Clausius – Rankine steam cycle (with one regenerative heater – deaerator) was carried out. The degree of regeneration (increase of the thermal efficiency) for cycle using the regenerative injector was determined. Based on results the further research directions for complex plants using a steam jets are indicated.

HYDROGEN-OXYGEN STEAM GENERATOR FOR A CLOSED HYDROGEN COMBUSTION CYCLE

The paper analyzes the problems of combustion hydrogen in an oxygen medium for produce high-temperature steam that can be used to produce electricity at various power plants. For example, at the nuclear power plants, the use of a H2-O2 steam generator as part of a hydrogen energy complex makes it possible to increase its power and efficiency in the operational mode due to steam-hydrogen overheating of the main working fluid of a steam-turbine plant. In addition, the use of the hydrogen energy complex makes it possible to adapt the nuclear power plants to variable electric load schedules in conditions of increasing the share of nuclear power plants and to develop environmentally friendly technologies for the production of electricity. The paper considers a new solution of the problem of effective and safe use of hydrogen energy at NPPs with a hydrogen energy complex.Technical solutions for the combustion of hydrogen in the oxygen medium using direct injection of cooling water or steam in the combustion products have a significant drawback – the effect of “quenching” when injecting water or water vapor which leads to a decrease in the efficiency of recombination during cooling of combustion products that is expressed in an increase fraction of non-condensable gases. In this case, the supply of such a mixture to the steam cycle is unsafe, because this can lead to a dangerous increase in the concentration of unburned hydrogen in the flowing part of the steam turbine plant. In order to solve this problem, the authors have proposed a closed hydrogen cycle and a hydrogen vapor overheating system based on it, and carried out a study of a closed hydrogen combustion system which completely eliminates hydrogen from entering the working fluid of the steam cycle and ensures its complete oxidation due to some excess of circulating oxygen.The paper considers two types of hydrogen-oxygen combustion chambers for the system of safe generating of superheated steam using hydrogen in nuclear power plant cycle by using a closed system for burning hydrogen in an oxygen medium. As a result of mathematical modeling of combustion processes and heat and mass transfer, we have determined the required parameters of a hydrogen-oxygen steam generator taking into account the temperature regime of its operation, and a power range of hydrogen-oxygen steam generators with the proposed combustion chamber design.

Influence of inter nal relative efficiency of steam turbine compartments on the performance of steam turbine cogeneration plant

The paper considers a steam turbine cogeneration plant that includes a back-pressure steam turbine and a natural gas-fired steam boiler that enables exhaust gas heat recovery, which is rather promising for the isolated heat and electricity consumers. A design and verification mathematical model of the steam turbine plant was developed. The focus is made on the optimization studies into the effect of the relative efficiency of turbine compartments on the performance indices of the steam turbine cogeneration plant with an installed electric capacity of 50 MW that uses the heat of steam contained in the combustion products of the boiler for heating the feed-water of the heat network.