"3E"分析和工作流体选择用于地热大温差利用的热电联产系统
Jiahui Yin1, Bing Zhu1, Yiming Zhang1
1Laboratory for Energy & Power Engineering of Electrical Engineering College, Guizhou University, Guiyang, Guizhou 550025, PR China.
ACS omega
|April 15, 2024
概括
本研究介绍了一个有机的兰金循环和吸收热交换器系统,用于低温地热能源. 它通过优化工作流体以提高效率来提高地热热的利用率和环境保护.
科学领域:
- 可再生能源工程可再生能源工程
- 热力学是一种热力学.
- 环境科学 环境科学
背景情况:
- 地热能为化石燃料提供了一个清洁的替代品,但低温来源对热电联产系统 (CHP) 提出了利用挑战.
- 当前的热电联热系统在使用低温地热热量时通常具有有限的效率.
研究的目的:
- 设计和分析一种新的热联产系统,将有机兰金循环 (ORC) 和吸收热交换器 (AHE) 结合起来.
- 评估使用低温地热热 (85°C) 的拟议系统的热效率,能量效率和经济可行性.
- 确定最佳的工作流体,以最大限度地提高系统性能.
主要方法:
- 系统设计集成ORC和AHE用于低温地热应用.
- 热力学和运动分析以评估系统性能.
- 经济分析以确定平衡能源成本 (LCOE).
- 对不同工作流体进行比较研究,以找到最佳选择.
主要成果:
- 拟议系统的最佳工作流体被确定为R245fa,达到61.39%的能量效率.
- 该系统在使用R245fa.时,即使在热源出口温度为23°C的低温度下,也表现出有效的运行.
- 使用R22作为工作流体时,达到0.082美元/千瓦时的最低平衡能源成本 (LCOE).
结论:
- 设计的ORC-AHE联合发电系统有效地提高了低温地热资源的利用率.
- R245fa是最大限度地提高能量效率的最佳流体,而R22则提供了最经济的操作.
- 该系统为清洁能源发电提供了可行的解决方案,减少了对化石燃料的依赖.
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