In this study, several heat-integrated distillation processes are compared to separate the close-boiling cyclohexanone (CHON)-cyclohexanol (CHXA) for improving energy efficiency. A 4-column scheme, including two light ends columns in DRP (distillation with recycle process), a CHON column and a CHXA column, is introduced as the prototype scheme. To make improvement, light and heavy split DRP – are compared for energy optimization upon the prototype. The light split DRP turns out to be superior and thus used for subsequent steps. Four heat-integrated schemes including double-effect distillation (DED), heat pump assisted distillation (HPAD), DED plus HPAD (DEHP) and double HPAD (DHPAD) are sequentially suggested and evaluated based on total annualized cost (TAC). The results show TAC reductions from the prototype of 32.2%, 23.6%, 29.2% and 10.8% for DED, HPAD, DEHP and DHPAD, respectively. The DED scheme requires the lowest TAC due to the 48.4% operating cost and 8% capital cost saving, whereas the DEHP scheme has the lowest 56.3% operating cost reduction with 11.1% more capital investment. The line of thinking in this work will benefit in other close-boiling systems for higher energetic efficiency and economic profit.

在这项研究中，对几种热集成蒸馏工艺进行了比较，以分离出密闭的环己酮（CHON）-环己醇（CHXA）以提高能源效率。作为原型方案，引入了一个4列方案，其中包括DRP中的两个轻馏分塔（循环过程蒸馏），一个CHON柱和一个CHXA柱。为了进行改进，对轻型和重型DRP进行了比较，以对原型进行能源优化。分光DRP证明是优越的，因此可用于后续步骤。依次提出了四种热集成方案，包括双效蒸馏（DED），热泵辅助蒸馏（HPAD），DED加HPAD（DEHP）和双HPAD（DHPAD），并根据总年度成本（TAC）进行了评估。结果显示，与原型相比，TAC减少了32.2％，23.6％，29.2％和10。DED，HPAD，DEHP和DHPAD分别为8％。DED方案所需的TAC最低，因为运营成本降低了48.4％，节省了8％的资本成本；而DEHP方案的运营成本降低了最低的56.3％，而资本投资则增加了11.1％。这项工作的思路将有益于其他密闭系统，以提高能源效率和经济效益。