Wpływ systemu separacji CO₂ NA efektywność elektrowni weglowej na parametry nadkrytyczne

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.