Open-cycle vapor compression heat pump

Large quantities of low-grade energy in the form of low-pressure steam and low-temperature heat are often discharged to the environment by industry. The practical and economical recovery of energy from these sources is often limited by the number of applications that can directly use low-temperature heat. Thermo Electron has developed an open-cycle steam heat pump system capable of the direct recovery and upgrading of low-grade waste energy. The system compresses low-pressure waste steam (or steam made from sources of low-temperature waste heat) to produce high-pressure steam suitable for use in industrial processes. A prototype system has been developed that is capable of recovering and recompressing up to 10,000 lb/hr of waste steam, while using only 50 percent of the fuel that would be required to produce comparable steam in a boiler.