Based on the characteristics of sewage from beauty salons,a simulation model of a small sewage source heat pump triple supply system that can be applied to such places is established to optimize the operating conditio...Based on the characteristics of sewage from beauty salons,a simulation model of a small sewage source heat pump triple supply system that can be applied to such places is established to optimize the operating conditions of the system.The results show that with the increase of sewage temperature and flow,the performance of the system also increases.In summer conditions,the system provides cooling,recovers waste heat and condensed heat from sewage,with a COP value of 8.97;in winter conditions,the system heats and produces hot water,with a COP value of 2.44;in transitional seasons,only hot water is produced.The COP value is 2.75.Compared with the traditional systems which refers to the air source heat pump and hot water boiler system currently used in beauty salons,this system can save energy by 50.9%.展开更多
The building sector contributes a large ratio of final energy consumption,and improving building energy efficiency is expected to play a significant role in mitigating its carbon dioxide emission.Herein,we collected t...The building sector contributes a large ratio of final energy consumption,and improving building energy efficiency is expected to play a significant role in mitigating its carbon dioxide emission.Herein,we collected the on-site measurement data to investigate the techno-economic performances of different heat pump types that exist in building space heating projects in Qingdao,China.An in-depth analysis revealed the temperature variations of measured low-grade heat sources over the whole heating supply period,and urban sewage water shows high stable heat energy quality compared with seawater and geothermal heat resources.Operational behaviors including cycling inlet and outlet temperature of the selected heat pumps were illustrated,and analysis evaluated detailed effects of operational parameters on energy efficiency performances.Then the relationship between COPs distributions of heat pumps and operational conditions was examined further,and the positive effect of the rising temperature of heat sources on energy efficiency improvement of heat pump is highlighted when the heating supply temperature is higher.Furthermore,we analyzed the economic and carbon emission performance of the heat pump system,and results show that electricity price plays a vital role in the lifespan energy cost saving potential,and the heat pump could serve as a promising approach in reducing CO_(2) related to the building space heating.Finally,we recommended suggestions for improving the overall energy efficiency and cost competitiveness of decentralized heat pump systems for building space heating.展开更多
Internal combustion engine-based poly-generation systems have been widely used for energy savings and emissions reductions.To maximize their thermodynamic and environmental performance potentials,the efficient recover...Internal combustion engine-based poly-generation systems have been widely used for energy savings and emissions reductions.To maximize their thermodynamic and environmental performance potentials,the efficient recovery of flue gas and jacket water heat is essential.In a conventional internal combustion engine-based steam and power cogeneration system,the low-temperature(less than 170°C)heat from flue gas and jacket water is usually directly discharged to the environment,which dramatically reduces the thermal and economic performance.In this work,a high-temperature heat pump is employed to recover this part of low-temperature heat for steam generation.The sensible heat of the flue gas and jacket water is cascade utilized in a steam generator and a heat pump.Simulation results show that the process steam yield of the proposed system is almost doubled(increased by 703 kg/h)compared to that of an engine-based cogeneration system without a heat pump.The proposed system can reduce natural gas consumption,C 02 and NOx emissions by approximately 199069 m3,372.64 tons and 3.02 tons per year,respectively,with a primary energy ratio and exergy efficiency of 72.52%and 46.28%,respectively.Moreover,the proposed system has a lower payback period with a value of 5.11 years,and the determining factors that affect the payback period are natural gas and electricity prices.The total net present value of the proposed system within its lifespan is 2441581 USD,and an extra profit of 785748 USD can be obtained compared to the reference system.This is a promising approach for replacing gas boilers for process steam production in industrial sectors.展开更多
基金the Science and Technology Program Project of the Ministry of Housing and Urban-Rural Development“Research on Indoor Thermal Environment Based on Zero Energy Building Technology in Hot Summer and Cold Winter Area”(2017-K1-014)Hubei Provincial Natural Fund Youth Fund“Technology and Evaluation of Multi-energy Complementary Energy Supply for Rural Residential Buildings in Hubei”(2017CFB311).
文摘Based on the characteristics of sewage from beauty salons,a simulation model of a small sewage source heat pump triple supply system that can be applied to such places is established to optimize the operating conditions of the system.The results show that with the increase of sewage temperature and flow,the performance of the system also increases.In summer conditions,the system provides cooling,recovers waste heat and condensed heat from sewage,with a COP value of 8.97;in winter conditions,the system heats and produces hot water,with a COP value of 2.44;in transitional seasons,only hot water is produced.The COP value is 2.75.Compared with the traditional systems which refers to the air source heat pump and hot water boiler system currently used in beauty salons,this system can save energy by 50.9%.
基金This research was funded by Development of the Healthy and Low-Carbon Residential House with Smart Home Environment Management System,Grant No.2019GSF110003Research on the energy efficiency and health performance improvement of building operations based on lifecycle carbon emissions reduction Grant No.2018YFE0106100.We gratefully acknowledge the help from ASSURAN International Scholarship Foundation.
文摘The building sector contributes a large ratio of final energy consumption,and improving building energy efficiency is expected to play a significant role in mitigating its carbon dioxide emission.Herein,we collected the on-site measurement data to investigate the techno-economic performances of different heat pump types that exist in building space heating projects in Qingdao,China.An in-depth analysis revealed the temperature variations of measured low-grade heat sources over the whole heating supply period,and urban sewage water shows high stable heat energy quality compared with seawater and geothermal heat resources.Operational behaviors including cycling inlet and outlet temperature of the selected heat pumps were illustrated,and analysis evaluated detailed effects of operational parameters on energy efficiency performances.Then the relationship between COPs distributions of heat pumps and operational conditions was examined further,and the positive effect of the rising temperature of heat sources on energy efficiency improvement of heat pump is highlighted when the heating supply temperature is higher.Furthermore,we analyzed the economic and carbon emission performance of the heat pump system,and results show that electricity price plays a vital role in the lifespan energy cost saving potential,and the heat pump could serve as a promising approach in reducing CO_(2) related to the building space heating.Finally,we recommended suggestions for improving the overall energy efficiency and cost competitiveness of decentralized heat pump systems for building space heating.
基金This work was supported by the National Key Research and Development Program of China(No.2016YFF0201503).
文摘Internal combustion engine-based poly-generation systems have been widely used for energy savings and emissions reductions.To maximize their thermodynamic and environmental performance potentials,the efficient recovery of flue gas and jacket water heat is essential.In a conventional internal combustion engine-based steam and power cogeneration system,the low-temperature(less than 170°C)heat from flue gas and jacket water is usually directly discharged to the environment,which dramatically reduces the thermal and economic performance.In this work,a high-temperature heat pump is employed to recover this part of low-temperature heat for steam generation.The sensible heat of the flue gas and jacket water is cascade utilized in a steam generator and a heat pump.Simulation results show that the process steam yield of the proposed system is almost doubled(increased by 703 kg/h)compared to that of an engine-based cogeneration system without a heat pump.The proposed system can reduce natural gas consumption,C 02 and NOx emissions by approximately 199069 m3,372.64 tons and 3.02 tons per year,respectively,with a primary energy ratio and exergy efficiency of 72.52%and 46.28%,respectively.Moreover,the proposed system has a lower payback period with a value of 5.11 years,and the determining factors that affect the payback period are natural gas and electricity prices.The total net present value of the proposed system within its lifespan is 2441581 USD,and an extra profit of 785748 USD can be obtained compared to the reference system.This is a promising approach for replacing gas boilers for process steam production in industrial sectors.
