Abstract: Steady-state simulation of traditional cyclohexanone distillation process was established by Aspen Plus, and calculation for main equipments were carried out in this simulation. Analysis of gas-liquid phase composition in the light column was conducted, and the results showed that cyclohexanone composition on the fifth theoretical plate at the top of light column had reached the product quality requirements. Based on the process simulation, a new process of cyclohexanone distillation with side stream was proposed. Through modifying the cyclohexanone column, the light components were separated on the top of cyclohexanone column, and the cyclohexanone product was withdrawal by a side stream simultaneously. In the new process, the separation of light components and cyclohexanone purification were conducted in a single column, while the light column and auxiliary equipments in the conventional process were eliminated. The optimized simulation results showed that, the theoretical plate number of the new cyclohexanone column was 80, and the cyclohexanone product (mass fraction 99.8%) was extracted from the 10th theoretical plate at the top of the column. In the new process, the gas-liquid load in the cyclohexanone column was the same as that of the traditional scheme. As a result, the cyclohexanone column had the same diameter as the existing one, and 15 more theoretical plates were required on the top of the new column. Compared with the conventional process, the new process can save energy more than 25% and improve the yield of cyclohexanone product. Additionally, the new process had the advantages of saving construction land and equipment investment.

Key words: simulation, distillation, light column, cyclohexanone column, side stream, optimization

摘要： 针对传统环己酮蒸馏工艺，本文采用Aspen Plus建立了稳态流程模型，并对主要设备进行了模拟计算。通过对轻塔内气液相组成分析，结果表明轻塔顶部第5块理论板上环己酮已达到产品质量要求。在此基础上，提出了带侧线采出的环己酮蒸馏新工艺。根据新工艺对环己酮塔进行了改造，采用塔顶采出轻组分杂质，侧线采出满足产品质量要求的环己酮，实现了单塔同时进行轻组分和环己酮产品的分离提纯，省去了传统工艺中的轻塔及配套设备。优化模拟计算结果表明，新工艺中环己酮塔理论塔板数为80，在塔顶第10块理论板上即可采出环己酮产品（质量分数99.8%）。新工艺中的环己酮塔气液相负荷与传统工艺中相同，因此塔径可维持不变，仅需在塔顶增加15块理论板即可满足分离要求。与传统工艺相比，新工艺可节能25%以上，提高了环己酮产品收率，同时具有节约建设用地和设备投资的优势。

关键词: 模拟, 蒸馏, 轻塔, 环己酮塔, 侧线采出, 优化