膜性能变化与温度和料成分对溶剂干燥的蒸发和蒸汽透系统设计的影响
1U.S. Environmental Protection Agency, Office of Research and Development, Center for Environmental Solutions and Emergency Response, Cincinnati, OH, USA.
概括
考虑到在蒸发 (PV) 和蒸汽透 (VP) 中变化的膜透性,这将大大改变从有机溶剂中去除水的预测. 可变的透度会影响膜面积要求和透成分,改善过程估计.
科学领域:
- 化学工程是化学工程的重要组成部分.
- 材料科学 材料科学 材料科学
- 分离过程 分离过程.
背景情况:
- 有机溶剂和生物燃料中的水污染使生产和再利用复杂化,原因是亚热的形成.
- 蒸发 (PV) 和蒸汽透 (VP) 是基于膜的技术,通过选择性运输来脱水这些混合物.
- 之前的研究通过假设恒定的膜透性来简化过程建模.
研究的目的:
- 研究可变膜透度对光伏和光伏系统预测性能的影响.
- 通过结合组合和取决于温度的透性数据来完善工艺设计计算.
主要方法:
- 将可变透度的多参数表达式集成到现有的PV/VP电子表格计算器中.
- 通过使用文学数据验证了使用NaA焦和聚乙烯醇 (PVA) 膜对乙醇/水脱水的模型.
主要成果:
- 可变的膜透率导致所需的膜面积在与恒定透率假设相比有20-30%的差异.
- 构成依赖的透性的影响对NaA膜在乙醇转移到透物方面最为显著.
- 差异来自于在水度范围的极端确定透度.
结论:
- 包括可变的膜透度 (取决于组成和温度) 在PV/VP过程中显著改变了膜面积和透成分的预测.
- 准确的工艺性能估计需要考虑度和温度的依赖性,特别是当在狭窄范围之外运行时.
- 这种方法提高了设计和优化溶剂脱水系统的可靠性.
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