Analysis on thermal characteristics of high back pressure heating retrofit for large-scale steam turbine units

Abstract

High back pressure heating with large-scale steam turbine units boasts preponderant heating capacity and preferable integrated utilization of energy while suffering high operation and maintenance cost and low operation flexibility. First, the high back pressure heating retrofit technology is introduced. Then, a model to analyze off-design performance of turbine and condenser for a 350MW heating unit was established using EBSILON software, by which quantitative calculation was performed of the influence of the key factors, so as to attain thermal characteristics of high back pressure heating. Finally, the paper was ended with multivariate analysis of the key factors in a combination of the theoretical analysis, the calculation results and the actual operating environment of the 350MW heating unit, in a bid to outline a change range of each factor. It thereby provided reference for selection of key parameters, feasibility analysis and operation economic analysis in high back pressure heating retrofit.