外文翻譯---熱泵的應(yīng)用(文件)
【正文】 Table 1 summarises typical temperature requirements for various heat and cold distribution systems. Table 1: Typical delivery temperatures for various heat and cold distribution systems. Application Supply temperature range (176。C. Water distribution systems (hydronic systems) are predominantly used in Europe, Canada and the north eastern part of the United States. Conventional radiator systems require high distribution temperatures, typically 6090176。 o drying/dehumidification。 (. repressed process vapour), although other process vapours are also used, notably in the (petro) chemical industry. o Closedcycle pression heat pumps are described in the section Heat pump technology . Currently applied working fluids limit the maximum output temperature to 120 篊 . o Absorption heat pumps (Type I) are not widely used in industrial applications. Some have been realised to recover heat from refuse incineration plants, notably in Sweden and Denmark. Current systems with water/lithium bromide as working pair achieve an output temperature of 100篊 and a temperature lift of 65 篊 . The COP typically ranges from to . The new generation of advanced absorption heat pump systems will have higher output temperatures (up to 260 篊 ) and higher temperature lifts. o Heat transformers (Type II) have the same main ponents and working principle as absorption heat pumps. With a heat transformer waste heat can be upgraded, virtually without the use of external drive energy. Waste heat of a medium temperature (. between the demand level and the environmental level) is supplied to the evaporator and generator. Useful heat of a higher temperature is given off in the absorber. All current systems use water and lithium bromide as working pair. These heat transformers can achieve a delivery temperatures up to 150 篊 , typically with a lift of 50 篊 . COPs under these conditions range from to . 第 3 頁(yè) o Reverse Braytoncycle heat pumps recover solvents from gases in many processes. Solvent loaden air is pressed, and then expanded. The air cools through the expansion, and the solvents condense and are recovered. Further expansion (with the associated additional cooling, condensation and solvent recovery) takes place in a turbine, which drives the pressor. 2). Applications Industrial heat pumps are mainly used for: o space heating。working fluid39。 o steam production。 o concentration. When heat pumps are used in drying, evaporation and distillation processes, heat is recycled within the process. For space heating, heating of process streams and steam production, heat pumps utilise (waste) heat sources between 20 篊 and 100 篊 . The most mon waste heat streams in industry are cooling water, effluent, condensate, moisture, and condenser heat from refrigeration plants. Because of the fluctuation in waste heat supply, it can be necessary to use large storage tanks for accumulation to ensure stable operation of the heat pump. o Space heating: Heat pumps can utilise conventional heat sources for heating of greenhouses and industrial buildings, or they can recover industrial waste heat that could 第 4 頁(yè) not be used directly, and pro
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