The influence of membrane separation on the efficiency of a coal fired power plant

The paper presents an algorithm for the determination of power plant power loses due to the membrane separation of CO₂ from the flue gases. For the investigation a supercritical coal fired block with a high efficiency of generating electricity has been chosen. For the purpose of separating CO₂ from the flue gases a membrane module with a determined surface area was used. Calculations concerning the membrane separation of CO₂ were carried out with use of the program Aspen Custom Modeler 2004. For the assessment of the separation process two indices were applied: the mole fraction of CO₂ in the permeate and the recovery ratio of CO₂. These quantities were determined in relation to the properties of the membranes (i.e. their permeability of CO₂ and their selectivity) and the pressure of the flue gases and the pressure of the permeate. The minimum losses of the power rating of the power plant have been determined on the calculated indices.