This paper presents an extensive study of the heat pump cycle and associated working fluids to generate electricity from low temperature industrial waste heat. An Aspen Plus simulation has been developed to evaluate t...This paper presents an extensive study of the heat pump cycle and associated working fluids to generate electricity from low temperature industrial waste heat. An Aspen Plus simulation has been developed to evaluate the effect of various working fluids on the net heat pump efficiency over a wide range of turbine inlet temperatures between 50℃ and 250℃. One hundred eight （108） refi＇igerants were investigated from the environmental classifications of Hydrochlorofluorocarbons （HCFC）, Hydrofluorocarbons （HFC）, Chlorofluorocarbons （CFC） and Hydrocarbons （HC） with boiling points between -88.65 ℃ and 110.65℃. Net efficiency, which ranged from 0.1% to 25.8% in this work tends to increases with the temperature of the waste heat. Results of the present study demonstrate that working fluid R41 （with source temperature of 44 ℃） provides the maximum efficiency among those evaluated. Refrigerants R13B1 and R32 provide the best efficiency for waste heat source temperatures ranges 60 - 67 ℃ and 68 - 78℃ respectively. Ammonia shows the highest efficiency from 79℃ to 132 ℃. Refrigerants R31, R21, 17,30 and benzene perform well in the temperature ranges 133-151 ℃, 152-178 ℃, 179-236℃ and 237-250 ℃respectively. The optimal heat pump systems are applied to the hybrid copper sulfate-copper oxide thermochemical cycle for hydrogen production from water. 100.8 MW of electrical energy is produced, which increased the efficiency from 24.1% to 25.9%.展开更多
A large magnitude-9.0 earthquake struck northeast Japan on March 11, 2011. Thirty minutes later, a tsunami reached Tokyo Electric Power Corporation （TEPCO）＇s Fukushima Daiichi nuclear power station, and the emergen...A large magnitude-9.0 earthquake struck northeast Japan on March 11, 2011. Thirty minutes later, a tsunami reached Tokyo Electric Power Corporation （TEPCO）＇s Fukushima Daiichi nuclear power station, and the emergency diesel generators submerged under water. Three units of the reactor experienced meltdown, and hydrogen explosions occurred at reactor houses. The RIKEN Nishina Center （RNC） contributed to the radiation screening effort by providing human resources, instruments, and transportation. The RNC also carried out extraction work and sample tests for soil contamination. Last summer, RIKEN was legally required to save 15% （equivalent to 3.3 MW） of its allocated electricity in its contract, making it extremely difficult to conduct experiments using accelerators. Accelerator operation was thus reduced to a minimum during the first half of the year. The RNC has a gas-turbine-based co-generation system （CGS） with an electrical capacity of 6.5 MW. The CGS was operated non-stop until the end of the year. RIKEN is constructing two sets of CGSs, each with a capacity of 1.5 MW to be commissioned this autumn.展开更多
文摘This paper presents an extensive study of the heat pump cycle and associated working fluids to generate electricity from low temperature industrial waste heat. An Aspen Plus simulation has been developed to evaluate the effect of various working fluids on the net heat pump efficiency over a wide range of turbine inlet temperatures between 50℃ and 250℃. One hundred eight （108） refi＇igerants were investigated from the environmental classifications of Hydrochlorofluorocarbons （HCFC）, Hydrofluorocarbons （HFC）, Chlorofluorocarbons （CFC） and Hydrocarbons （HC） with boiling points between -88.65 ℃ and 110.65℃. Net efficiency, which ranged from 0.1% to 25.8% in this work tends to increases with the temperature of the waste heat. Results of the present study demonstrate that working fluid R41 （with source temperature of 44 ℃） provides the maximum efficiency among those evaluated. Refrigerants R13B1 and R32 provide the best efficiency for waste heat source temperatures ranges 60 - 67 ℃ and 68 - 78℃ respectively. Ammonia shows the highest efficiency from 79℃ to 132 ℃. Refrigerants R31, R21, 17,30 and benzene perform well in the temperature ranges 133-151 ℃, 152-178 ℃, 179-236℃ and 237-250 ℃respectively. The optimal heat pump systems are applied to the hybrid copper sulfate-copper oxide thermochemical cycle for hydrogen production from water. 100.8 MW of electrical energy is produced, which increased the efficiency from 24.1% to 25.9%.
文摘A large magnitude-9.0 earthquake struck northeast Japan on March 11, 2011. Thirty minutes later, a tsunami reached Tokyo Electric Power Corporation （TEPCO）＇s Fukushima Daiichi nuclear power station, and the emergency diesel generators submerged under water. Three units of the reactor experienced meltdown, and hydrogen explosions occurred at reactor houses. The RIKEN Nishina Center （RNC） contributed to the radiation screening effort by providing human resources, instruments, and transportation. The RNC also carried out extraction work and sample tests for soil contamination. Last summer, RIKEN was legally required to save 15% （equivalent to 3.3 MW） of its allocated electricity in its contract, making it extremely difficult to conduct experiments using accelerators. Accelerator operation was thus reduced to a minimum during the first half of the year. The RNC has a gas-turbine-based co-generation system （CGS） with an electrical capacity of 6.5 MW. The CGS was operated non-stop until the end of the year. RIKEN is constructing two sets of CGSs, each with a capacity of 1.5 MW to be commissioned this autumn.
