Heat and power networks in process design. Part I: Criteria for placement of heat engines and heat pumps in process networks



The general problem of heat and power integration in process networks is complex and to date not fully understood. The subject covers site combined heat and power, on-plant power generation, heat pumps, and refrigeration systems. This paper is the first of a two-part series and explains the concept of “appropriate” heat engine and heat pump placement in process networks based on a fundamental new insight. “Appropriate” placement takes advantage of integration opportunities with the remainder of the process and yields marginal efficiencies far greater than could be achieved through stand-alone heat engines. Conversely, “inappropriate” placement can never offer an advantage over stand-alone systems. Part II describes procedures for preliminary design, involving heat engine, and heat pump equipment selection and performance assessment.