Conventional pressure swing adsorption (PSA) processes can only produce one high purity product in a single stage, whereas the state-of-art dual-reflux PSA (DR-PSA) can produce two high purity products simultaneously. However, multicomponent gas separation is often required in the industry, targeting at recovering several valued products at the same time. In this study, we propose a novel adsorption process, namely triple-reflux PSA (TR-PSA), to separate three components simultaneously. A middle product outlet and a middle reflux stream were introduced to the adsorption columns of a conventional DR-PSA process to separate ternary mixtures of nitrogen, methane, and helium. Nonisothermal dynamic models were built to investigate the impacts of operating parameters particularly the location of the middle reflux/product stream and the middle reflux flow rates. Results showed that the TR-PSA process successfully separated ternary mixtures obtaining three enriched products simultaneously in a single stage, yielding a separation performance comparable to that of the double-stage DR-PSA with significantly lower capital and energy cost.

中文翻译：

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三重回流变压吸附法分离 He/N2/CH4 三元混合物

传统的变压吸附 (PSA) 工艺在一个阶段只能生产一种高纯度产品，而最先进的双回流 PSA (DR-PSA) 可以同时生产两种高纯度产品。然而，工业中通常需要多组分气体分离，旨在同时回收几种有价值的产品。在这项研究中，我们提出了一种新的吸附工艺，即三重回流 PSA (TR-PSA)，可同时分离三种组分。将中间产物出口和中间回流物流引入常规 DR-PSA 工艺的吸附塔，以分离氮气、甲烷和氦气的三元混合物。建立非等温动态模型来研究操作参数的影响，特别是中间回流/产品流的位置和中间回流流速。结果表明，TR-PSA 工艺成功地分离了三元混合物，在一个阶段同时获得了三种富集产品，其分离性能与双阶段 DR-PSA 相当，且资本和能源成本显着降低。