针对混合制冷剂循环液化天然气流程能耗高、效率低的现状,运用HYSYS软件对液化流程模型进行优化,分析评价表明,压缩机、冷却器、多股流换热器、节流阀及混合器的损失依次减少。探讨了流体压力、温度、压缩比等参数对压缩过程不可...针对混合制冷剂循环液化天然气流程能耗高、效率低的现状,运用HYSYS软件对液化流程模型进行优化,分析评价表明,压缩机、冷却器、多股流换热器、节流阀及混合器的损失依次减少。探讨了流体压力、温度、压缩比等参数对压缩过程不可逆性的影响,第一段压缩机出口压力为1 074 k Pa、压缩比为2.02,第二段压缩机进口温度为40℃、压缩比为3.63时,最小压缩机比功耗、损失为5.98 k Wh/kmol、15 840.06 k W。优化换热器操作,保持夹点温差、对数平均温差约3、5℃,换热器损失减少41%。借助分析原料气的CP-T分布,在满足不同温区所需冷量的基础上,合理配置制冷剂组分,调整制冷剂蒸发压力可降低换热过程损失。展开更多
The paper presents an investigation of energy and exergy analysis of an existing ORC （organic rankine cycle） unit powered by hot geothermal water. The validated model of this unit was used to examine 25 refrigerants...The paper presents an investigation of energy and exergy analysis of an existing ORC （organic rankine cycle） unit powered by hot geothermal water. The validated model of this unit was used to examine 25 refrigerants belonging to different chemical compositions. The study revealed that R141b and R123 produced the best net power, energy efficiency, and exergy efficiency, whereas R125 was the lowest. Hydrofluorocarbons （except R143a）, hydrocarbons, and inorganic reflected attractive energy and exergy efficiencies. All investigated mixtures gained low performance compared with other studied candidates. The R245ca was the best among the hydrofluorocarbons studied refrigerants, and R501 was the best among the mixture refrigerants. Furthermore, within the ORC system, the evaporator was found to have the highest exergy destruction and the refrigerant pump was the lowest.展开更多
文摘针对混合制冷剂循环液化天然气流程能耗高、效率低的现状,运用HYSYS软件对液化流程模型进行优化,分析评价表明,压缩机、冷却器、多股流换热器、节流阀及混合器的损失依次减少。探讨了流体压力、温度、压缩比等参数对压缩过程不可逆性的影响,第一段压缩机出口压力为1 074 k Pa、压缩比为2.02,第二段压缩机进口温度为40℃、压缩比为3.63时,最小压缩机比功耗、损失为5.98 k Wh/kmol、15 840.06 k W。优化换热器操作,保持夹点温差、对数平均温差约3、5℃,换热器损失减少41%。借助分析原料气的CP-T分布,在满足不同温区所需冷量的基础上,合理配置制冷剂组分,调整制冷剂蒸发压力可降低换热过程损失。
文摘The paper presents an investigation of energy and exergy analysis of an existing ORC （organic rankine cycle） unit powered by hot geothermal water. The validated model of this unit was used to examine 25 refrigerants belonging to different chemical compositions. The study revealed that R141b and R123 produced the best net power, energy efficiency, and exergy efficiency, whereas R125 was the lowest. Hydrofluorocarbons （except R143a）, hydrocarbons, and inorganic reflected attractive energy and exergy efficiencies. All investigated mixtures gained low performance compared with other studied candidates. The R245ca was the best among the hydrofluorocarbons studied refrigerants, and R501 was the best among the mixture refrigerants. Furthermore, within the ORC system, the evaporator was found to have the highest exergy destruction and the refrigerant pump was the lowest.
