Steam production process - obtains low pressure steam via heat exchange with vaporisable fluid in closed circuit

摘要

The process produces steam at two or more different pressures, part of the medium pressure steam being obtained by partial expansion in a turbine of high-pressure steam. Part of the low-pressure steam is obtained by vaporising water in a first heat exchanger with indirect contact with a vaporisable heat exchange fluid circulating in a closed cycle. This fluid is condensed in a first heat exchanger, expanded, and vapourised in a second heat exchanger by indirect contact with a heat source at a thermal level lower than that of saturated steam at the low pressure concerned. It is then compressed in a compressor which is mechanically driven by the turbine and returned to the first heat exchanger.