EAGER: Work Integration through Work Exchange Network Synthesis

EAGER：通过工作交换网络综合进行工作整合

• 批准号: 1443912
• 负责人: Yinlun Huang
• 金额: $ 6万
• 依托单位: Wayne State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-08-15 至 2017-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1443912&HistoricalAwards=false
• 关键词: EAGER; Work; Integration; through; Exchange

Over the past decade, accelerated natural resource depletion, greenhouse gas (GHG) emissions, the consequences of climate change, and economic globalization, among other factors, had industries reviewing their practices with a greater focus on sustainability. The results have been improvements in their operations evidenced by energy savings, waste reduction, and gains in productivity. But, according to the DOE Industrial Technology Program (ITP), the energy loss in the manufacturing sectors is still high (approximately 57% of the total energy consumed), and total combustion emissions have reached approximately 1,260 million metric tons of CO2e (carbon dioxide equivalents). The chemical process industries (CPI) account for approximately 20% of the total energy consumed in the U.S. This research project is aimed at improving energy conservation in chemical plants.Intellectual Merit:Heat and work are two common forms of energy in chemical plants. Heat integration, using heat exchanger networks (HENs), is a technique used for thermal energy recovery in the CPI. While process work is more expensive than process heat, using and reusing process work effectively has not been seriously studied. The research goal here is to develop work exchange networks (WENs) that are similar to HENs. From a thermodynamics point of view, heat flow, with temperature as the state variable, is directly related to thermal energy efficiency, while work flow, with pressure as the state variable, can be used to evaluate mechanical energy efficiency. The key mechanism of work integration is work exchange among coupled process streams due to pressure differences. This study is an investigation of using work integration in process systems engineering. The proposed thermodynamic analysis on work exchange under isothermal, non-isothermal, and adiabatic conditions will be used in the work exchange regions for thermodynamically feasible and economically justifiable mechanical energy recovery. Since a WEN is operated in a hybrid mode, the WEN synthesis methodology will be different from those for heat and mass exchanger networks, which are operated in a continuous mode. The methodological novelty will be also demonstrated by the approaches for pinch point identification, energy-cost target setting, and optimal process stream matching.Broader Impacts :In a variety of chemical manufacturing systems, process streams need to be pressurized, which requires work for compression, while other processes can produce work through expansion. Ammonia synthesis, reverse osmosis, and freezing purification are among well-known examples. Another example is the gas processing industry, where high-pressure natural gas needs to be cooled with liquid CO2 and then expanded to a lower pressure to exchange heat with liquid N2, and it is then further depressurized in a turbine to reach its storage pressure. If the available mechanical energy in the high-pressure streams is utilized to pressurize the lower pressure streams, the mechanical energy recovery can greatly reduce operating cost. This is of not only economic significance but also has environmental implications, as energy efficiency improvement could help reduce CO2 emission.

在过去的十年中，加速的自然资源耗竭，温室气体（GHG）排放，气候变化的后果以及经济全球化等因素除其他因素外，行业审查了其实践，以更加关注可持续性。结果是通过节省能源，减少废物和生产力提高来改善其运营。但是，根据DOE工业技术计划（ITP），制造业的能源损失仍然很高（约占消耗总能源的57％），总燃烧排放量已达到约12.6亿吨CO2E（二氧化碳等效量）。化学过程行业（CPI）约占美国消耗的总能源的20％，该研究项目旨在改善化学植物的能源保护。智能优点：热量和工作是化学植物中的两种常见能量形式。 使用热交换器网络（Hens）的热整合是一种用于CPI热能回收的技术。虽然过程工作比过程热量更昂贵，但使用和重复使用过程工作尚未得到认真研究。这里的研究目标是开发与母鸡相似的工作交换网络（WEN）。 从热力学的角度来看，以温度作为状态变量的热流与热能效率直接相关，而以状态变量为状态的工作流量可用于评估机械能效效率。 工作整合的关键机制是由于压力差异而导致的过程流之间的工作交换。这项研究是关于在过程系统工程中使用工作整合的研究。在等温，非等热条件下进行工作交换的热力学分析将用于热力学上可行且经济合理的机械能回收的工作交换区域。由于WEN以混合模式运行，因此WEN合成方法将与以连续模式运行的热量和质量交换器网络不同。方法论新颖性还将通过捏点识别，能量成本目标设置和最佳过程流匹配的方法来证明。BRODER的影响：在各种化学制造系统中，过程流需要加压，这需要进行压缩，而其他过程可以通过扩展产生工作。氨合成，反渗透和冻结纯化是众所周知的例子。另一个例子是气体加工行业，其中高压天然气需要用液体二氧化碳冷却，然后扩大到较低的压力，以与液体N2交换热量，然后在涡轮机中进一步减压以达到其存储压力。如果利用高压流中的可用机械能加压较低的压力流，则机械能量回收可以大大降低工作成本。这不仅具有经济意义，而且具有环境的影响，因为提高能源效率可以帮助减少二氧化碳排放。