As a potentially viable renewable energy, Enhanced Geothermal Systems(EGSs) extract heat from hot dry rock(HDR) reservoirs to produce electricity and heat, which promotes the progress towards carbon peaking and carbon...As a potentially viable renewable energy, Enhanced Geothermal Systems(EGSs) extract heat from hot dry rock(HDR) reservoirs to produce electricity and heat, which promotes the progress towards carbon peaking and carbon neutralization. The main challenge for EGSs is to reduce the investment cost. In the present study, thermo-economic investigations of EGS projects are conducted. The effects of geofluid mass flow rate, wellhead temperature and loss rate on the thermo-economic performance of the EGS organic Rankine cycle(ORC) are studied. A performance comparison between EGS-ORC and the EGS combined heating and power system(CHP) is presented. Considering the CO_(2)emission reduction benefits, the influence of carbon emission trading price on the levelized cost of energy(LCOE) is also presented. It is indicated that the geofluid mass flow rate is a critical parameter in dictating the success of a project. Under the assumed typical working conditions, the LCOE of EGS-ORC and EGS-CHP systems are 24.72 and 16.1 cents/k Wh, respectively. Compared with the EGS-ORC system, the LCOE of the EGS-CHP system is reduced by 35%. EGS-CHP systems have the potential to be economically viable in the future. With carbon emission trading prices of 12.76 USD/ton, the LCOE can be reduced by approximately 8.5%.展开更多
To solve the problem of swelling and agglomeration of CaCl 2 during the process of ammonia adsorption and improve the performance of mass transfer,we present a new method for the preparation of adsorbent.The CaCl 2 is...To solve the problem of swelling and agglomeration of CaCl 2 during the process of ammonia adsorption and improve the performance of mass transfer,we present a new method for the preparation of adsorbent.The CaCl 2 is first immerged into sawdust by soaking method,then the composite adsorbent is prepared by carbonizing the mixture of CaCl 2 and sawdust.The SEM image and elements analysis indicated that the new adsorbent has high porosity and uniform distribution of CaCl 2 due to carbonization under temperature of 700°C.The performance testing of ammonia adsorption showed that under the conditions of evaporation temperature of 5°C and condensation temperature of 40°C,the ammonia uptake reaches 0.204,0.253 and 0.285 kg/kg,the specific cooling power(SCP) is 868.96,540.02 and 405.16 W/kg,and the average adsorption rate is 6.79×10 4,4.22×10 4 and 3.17×10 4 kg/kg/s when the adsorption time is 5,10 and 15 min,respectively.The problems of swelling and agglomeration of CaCl 2 are solved.展开更多
To develop a new composite adsorbent with high performance,fir sawdust and CaCl2are selected as raw materials.The mass transfer is enhanced by carbonizing and activating the sawdust and heat transfer is enhanced by ad...To develop a new composite adsorbent with high performance,fir sawdust and CaCl2are selected as raw materials.The mass transfer is enhanced by carbonizing and activating the sawdust and heat transfer is enhanced by adding expanded graphite into the adsorbent.The effect of the preparation temperature and the expanded graphite content on the adsorption performance is investigated.The results show that the new adsorbent exhibits a high adsorption performance due to its high porosity,uniform distribution and high content of CaCl2and high thermal conductivity.Also,the experimental results indicate that the rate of ammonia adsorption on the adsorbent depends on the expanded graphite content and the carbonization and activation temperature.The adsorbent prepared at 500°C and with the expanded graphite content of 30%has the best performance in terms of the adsorption refrigeration,which adsorbs ammonia as high as 0.37 g g 1at 10 min.展开更多
基金financial support provided by the National Key Research and Development Program of China(No.2018YFB1501805)China Geological Survey Project(Grant No.DD2019135,and No.DD20211336)。
文摘As a potentially viable renewable energy, Enhanced Geothermal Systems(EGSs) extract heat from hot dry rock(HDR) reservoirs to produce electricity and heat, which promotes the progress towards carbon peaking and carbon neutralization. The main challenge for EGSs is to reduce the investment cost. In the present study, thermo-economic investigations of EGS projects are conducted. The effects of geofluid mass flow rate, wellhead temperature and loss rate on the thermo-economic performance of the EGS organic Rankine cycle(ORC) are studied. A performance comparison between EGS-ORC and the EGS combined heating and power system(CHP) is presented. Considering the CO_(2)emission reduction benefits, the influence of carbon emission trading price on the levelized cost of energy(LCOE) is also presented. It is indicated that the geofluid mass flow rate is a critical parameter in dictating the success of a project. Under the assumed typical working conditions, the LCOE of EGS-ORC and EGS-CHP systems are 24.72 and 16.1 cents/k Wh, respectively. Compared with the EGS-ORC system, the LCOE of the EGS-CHP system is reduced by 35%. EGS-CHP systems have the potential to be economically viable in the future. With carbon emission trading prices of 12.76 USD/ton, the LCOE can be reduced by approximately 8.5%.
基金supported by the Chinese Academy of Sciences and Foreign Experts Bureau of Guangdong under the Adsorption Refrigeration Program (Grant nos. y007y51001 and 2010004)The structure and preparation process of the new adsorbent has a patent (China Patent 20111015-1114.2)
文摘To solve the problem of swelling and agglomeration of CaCl 2 during the process of ammonia adsorption and improve the performance of mass transfer,we present a new method for the preparation of adsorbent.The CaCl 2 is first immerged into sawdust by soaking method,then the composite adsorbent is prepared by carbonizing the mixture of CaCl 2 and sawdust.The SEM image and elements analysis indicated that the new adsorbent has high porosity and uniform distribution of CaCl 2 due to carbonization under temperature of 700°C.The performance testing of ammonia adsorption showed that under the conditions of evaporation temperature of 5°C and condensation temperature of 40°C,the ammonia uptake reaches 0.204,0.253 and 0.285 kg/kg,the specific cooling power(SCP) is 868.96,540.02 and 405.16 W/kg,and the average adsorption rate is 6.79×10 4,4.22×10 4 and 3.17×10 4 kg/kg/s when the adsorption time is 5,10 and 15 min,respectively.The problems of swelling and agglomeration of CaCl 2 are solved.
基金supported by the Innovation Program of Chinese Academy of Sciences(y007y51001)Comprehensive Strategic Cooperation Projects of Chinese Academy of Sciences and Guangdong Province(2012B091100263)
文摘To develop a new composite adsorbent with high performance,fir sawdust and CaCl2are selected as raw materials.The mass transfer is enhanced by carbonizing and activating the sawdust and heat transfer is enhanced by adding expanded graphite into the adsorbent.The effect of the preparation temperature and the expanded graphite content on the adsorption performance is investigated.The results show that the new adsorbent exhibits a high adsorption performance due to its high porosity,uniform distribution and high content of CaCl2and high thermal conductivity.Also,the experimental results indicate that the rate of ammonia adsorption on the adsorbent depends on the expanded graphite content and the carbonization and activation temperature.The adsorbent prepared at 500°C and with the expanded graphite content of 30%has the best performance in terms of the adsorption refrigeration,which adsorbs ammonia as high as 0.37 g g 1at 10 min.
