Trigeneration Turbine Units Based on Low Boiling Working Fluids
A. V. Ovsyannik, V. P. Kliuchinski
Abstract
A program that allows modeling, thermodynamically optimizing and performing exergetic analysis of more than a hundred different variations of the schemes of trigeneration turbine units based on low-boiling working fluids. With the aid of the program that had been developed, an exergetic analysis of six schemes of trigeneration turbine units on the organic Rankine cycle was performed, viz. on an overheated steam with a steam compression refrigeration unit; with an intermediate overheating of the working fluid and a steam compression refrigeration unit; on an overheated steam with a refrigeration unit with carbon dioxide production; with an intermediate overheating of the working fluid and a refrigeration unit with carbon dioxide production; on an overheated steam with a refrigeration unit with production carbon dioxide and cooling of the turbine condenser with liquid carbon dioxide; with intermediate overheating of the working fluid, a refrigeration unit with carbon dioxide production and cooling of the turbine unit condenser with liquid carbon dioxide. A gas turbine unit was used as an energy source for the above-mentioned schemes. The possibility of using the resulting liquid carbon dioxide to cool the condenser of a turbine unit on an organic Rankine cycle has been studied. A comparative analysis of two methods of obtaining cold (using a steam compression refrigeration unit and a refrigeration unit with carbon dioxide production) for use in trigeneration schemes has been carried out. The research was based on the method of exergetic analysis, the results of which are presented in the form of enlarged Grassmann – Shargut diagrams. A technical and economic analysis of the use of intermediate overheating in the organic Rankine cycle has been carried out, ozone-safe freon R245FA was used as the working fluid. Recommendations for the application of the studied trigeneration schemes on the organic Rankine cycle are formulated.