Entity

Time filter

Source Type


This paper presents the supercritical power unit of gross electrical equal to: 600 MW. This is a power plant working in the oxy-combustion technology, with a cryogenic air separation unit and a carbon capture and storage installation. In the fluidized bed boiler on the supercritical steam parameters 29 MPa/600 °C, a wet flue gas recirculation was applied. Each module, located in the structure of oxy plant was discussed. The assumptions used for the calculations and a methodology quantifying of the efficiency of electricity generation block was described. Values of energetic indices such as the boiler thermal efficiency, auxiliary power rates, and net efficiency of electricity generation, were specified. The results were compared with a reference power plant with a gross capacity of 600 MW, operating in the air-fired combustion.


Supercritical power plant analyzed in this paper, contains the following elements: steam turbine, hard coal fired oxy-type pulverized fuel boiler, air separation unit with four-end type high-temperature membrane and carbon dioxide capture unit. Gross electric power of the power plant is equal to 600 MW. Live steam thermodynamic parameters are 650 °C/30 MPa and reheated steam parameters are 670 °C/6 MPa. Under assumption of constant gross power of the analyzed power plant, a thermal boiler efficiency and auxiliary powers of mentioned above installations were designated as a function of oxygen recovery rate. They allowed to determine a net efficiency of the power plant for two oxygen recovery rates. This efficiency is lower by 8.3/9.4 percentage point than the reference power plant efficiency. Integration of all installation with steam turbine is crucial for the net efficiency increase. This operation allows to replace steam regenerative heat exchangers by gas-water heat exchangers. It allows to increase gross electrical power by up to 49 MW. As a result, the net efficiency of the analyzed power plant is 6.4/7.4 percentage points lower than the efficiency of the reference power plant. The economic analysis indicate that the oxy type power plants with integration of all installations with a steam turbine are profitable, because break-even price of electricity is lower by 9.53/12.53 PLN/MWh than the price for the reference power plant.


Electricity production by the FC-42/HLC fuel cell stacks would be impossible without autonomic system that controls auxiliary devices. Autonomic control system consists of fuel cell's voltage and current measuring unit with undervoltage and overcurrent protection, anode purge unit, compressor's control unit supplying air to cathode, measuring and regulating system unit which control coolant temperature and cooler ventilators. The article presents research results and operating mode of all four above mentioned subassemblies of automatic control system for FC-42/HLC-720W.


Kotowicz J.,Warsaw University of Technology | Janusz-Szymanska K.,Institute of Power Engineering and Turbomachinery of Poland
Rynek Energii | Year: 2011

In this paper the influence of CO2 separation system on the efficiency of a coal power plant was presented. For the analysis the pulverized coal power plant with the electric power rating at 460 MW, parameters of live steam 27.8 MPa/ 580°C and the temperature of reheated steam equal 600°C was selected. This power plant achieves a net efficiency equal to 41.43% (according to LHV). Two cases were analyzed. First, using oxy combustion technology in which oxygen is supplied from cryogenic air separation unit (ASU) and the second, with the use of CO2 membrane separation from flue gases arising from burning coal in the air. The use of oxy boiler, powered with oxygen from cryogenic ASU, and further compression of the exhausts arisen in this process up to the pressure of 20.68 MPa causes the efficiency decrease of 9.08 percentage points. It was calculated, that the use of membrane CO 2 separation and its further compression to the same pressure (20.68 MPa) will cause efficiency decrease only by about 6.13 percentage points. The use of waste heat from the separation process in the steam turbine cycle was proposed in this paper. It will decrease the electricity generation net efficiency by about 5.29 percentage points.


Janusz-Szymanska K.,Institute of Power Engineering and Turbomachinery of Poland | Kotowicz J.,Jest Dziekanem Wydzialu Inzynierii Srodowiska i Energetyki
Rynek Energii | Year: 2011

In this paper the influence of the CO2 separation system on the efficiency of a coal power plant was presented. For the analysis the pulverized coal power plant with the electric power rating at 900 MW and net efficiency equal to 45.46% was chosen. The analysis of the selection of a structure of the membrane module, pressure and the membrane surface area for CO2 recovery ratio and CO2 purity was performed. Two stage membrane module was proposed. This system allows to obtain CO2 purity at 0.9 and 90% separation degree of the total CO2 emission in the power plant. The analysis of the energy consumption of the CO2 membrane separation and CO2 compression process for its liquefaction was conducted. Such a CCS installation requires supply of the energy at the level of 142.36 MW (74.45 MW for the membrane separation and 67.91 MW for the CO2 compression) which corresponds to the energy intensity of the process equal to 0.94 MJ/kgCO2. It will decrease the electricity generation net efficiency to the level of 38.27%.

Discover hidden collaborations