低温精馏过程模拟及其分离特性分析(Ⅱ)带有侧线返回进料的低温精馏塔模拟

应用严格的热力学模型研究了带有侧线返回进料的氢同位素低温精馏塔的分离特性.根据氢同位素低温精馏体系的特点，以平衡级模型为基础建立了氢同位素低温精馏稳态模拟模型，确定了模型方程适宜的求解方法.塔的一股侧线出料流股经过一个平衡反应器完成平衡反应后，作为内部进料流股，与原外部进料混合后重新进入精馏塔内进行分离操作.通过对带有侧线返回进料的塔的计算模拟阐明了这一侧线流股对塔分离特性的影响.在平衡反应器内，HD部分分解为H₂和D₂，塔顶产品中H₂的浓度增加了8.635%，塔底D₂的浓度增加了11.327%.     

H2/HD/HT电解-精馏级联分离过程理论分析

为研究电解精馏级联氢同位素分离过程的规律性,建立了理论模型,并以H2/HD/HT为对象计算研究了系统分离行为。获得了电解和精馏过程系统的浓集行为： 电解池中HDO浓度从2.88×10-4 增长到 8.35×10-4, HTO浓度从1.0×10-6 增长到6.34×10-6;精馏柱再沸器中HD浓度达到0.033,HT浓度达到6.06×10-5。由于H/D和H/T电解池分离因子的差异,63.4%的HTO仍然留在电解池中,造成精馏柱再沸器中HT浓缩倍数不如HD。随时间的增长,脱氘（氚）率下降。     

H2/HD/HT电解-精馏级联分离过程理论分析

为研究电解精馏级联氢同位素分离过程的规律性,建立了理论模型,并以H2/HD/HT为对象计算研究了系统分离行为。获得了电解和精馏过程系统的浓集行为： 电解池中HDO浓度从2.88×10-4 增长到 8.35×10-4, HTO浓度从1.0×10-6 增长到6.34×10-6;精馏柱再沸器中HD浓度达到0.033,HT浓度达到6.06×10-5。由于H/D和H/T电解池分离因子的差异,63.4%的HTO仍然留在电解池中,造成精馏柱再沸器中HT浓缩倍数不如HD。随时间的增长,脱氘（氚）率下降。     

大豆油轻质馏分中有效成分的提取研究

采用侧线精馏耦合萃取精馏从大豆油轻质馏分中提取十一烷、十二烷及正癸醇的方法。以UNIQUAC方程为相平衡模型,利用Aspen plus软件对提取过程进行模拟研究,考察了塔板数、回流比、进出料位置及溶剂比等因素对侧线精馏和萃取精馏分离效果的影响,采用灵敏度分析对侧线精馏和萃取精馏分离条件进行优化,确定分离过程最佳条件。     

工业生产中醋酸甲酯回收技术的研究进展

综述了聚乙烯醇和精对苯二甲酸生产过程中分离回收醋酸甲酯的主要方法,并对加盐萃取精馏等盐效分离方法、催化精馏方法和萃取精馏方法进行比较研究。结果表明,加盐萃取精馏方法能分离出高纯度醋酸甲酯,且生产工艺简单,有较好的应用前景。     

间歇萃取精馏技术的进展

对间歇萃取精馏分离技术和进展进行了评述,主要从萃取精馏溶剂选择,操作方式,新型塔设备的研究,操作优化及过程模拟等几个方面,介绍了国内外关于间歇萃取精馏新兴分离技术的最新研究动态,最后指出了萃取精馏技术目前存在的问题和今后发展的方向。     

萃取精馏分离乙烷/乙烯的溶剂

引　言乙烯 /乙烷的分离是乙烯生产过程中非常重要的一步 .长期以来 ,低温精馏在烷烃 /烯烃分离中占主导地位[1] .尽管精馏是一种非常成熟的工艺 ,并且近期内不易被其他方法取代 ,但低温精馏一直存在着压缩功耗高 ,冷耗大 ,板数多的缺点 .例如 ,在一个 10 0多块塔板的精馏塔内分离乙烷 /乙烯 ,需要在 - 2 5℃的低温和 2 .30 6ＭＰａ的高压下操作[1] .所以研究人员一直致力于寻求一种高效、节能、低成本的方法 ,以取代低温精馏分离烷烃 /烯烃 .目前 ,文献报道[2～ 5] 中有关轻烃分离的方法主要有膜分离、吸附、吸收和萃取精馏等 .膜分离法具…     

循环精馏技术研究进展

在“碳中和”“碳达峰”的战略目标下,过程强化是实现绿色生产的关键技术之一。循环精馏作为一种基于过程强化理论的新型精馏技术,通过采用特定塔内构件和控制方案而改变传统精馏塔内气相和液相的流动方式,实现气液两相分别呈周期性独立运动SPM的操作模式。循环精馏技术理论上可实现塔内液相返混为零,使分离推动力最大化,具有处理能力大、能耗低及分离性能好等优点。相较传统精馏操作,循环精馏技术可使单板效率提高到140%～300%,能耗降低20%～30%。本文针对循环精馏技术的研究背景、工作原理、工业应用、两种专用塔板（Maleta塔板和COPS塔板）以及循环精馏技术在隔板塔和反应精馏等过程强化技术中的应用进行了综合论述。论文对循环精馏技术的控制方法和内构件研究中存在的问题进行了总结,并对循环精馏技术的发展方向和前景进行了展望。     

新型精馏集成技术用于混合硝基氯化苯分离的研究

介绍了硝基氯苯3种同分异构体的性质、用途及生产现状,分析了混合硝基氯苯分离的难点,对目前已有的分离方法进行了综述,指出了各种分离方法的优点和不足。提出了侧线精馏-萃取精馏-结晶相结合的新型精馏集成技术用于混合硝基氯苯的分离,与传统工艺相比,该过程工艺简单,分离效率高,分离的能耗大大降低。     

含氧煤层气甲烷提浓技术比较

含氧煤层气的主要成分是甲烷、氧气和氮气,为了回收利用煤层气中的甲烷,需要对煤层气进行脱氧和脱氮处理,以提高甲烷浓度.通过调研统计,甲烷提浓技术主要包括三种：含氧-低温精馏、脱氧-低温精馏和脱氧-吸附分离-液化技术.并从安全、造价和功耗三个方面对这三种提浓技术的工艺方案及特点进行分析和比较.研究结果表明：脱氧-低温精馏提浓技术的安全性高、造价较低,功耗居中.因此,含氧煤层气提浓甲烷推荐使用脱氧-低温精馏分离技术.     

同位素水精馏非稳态过程制备低氘水的研究与应用

根据水精馏过程中氢、氧稳定同位素的分离特性,以及同位素精馏的稳态和非稳态级联过程的理论分析和研究,应用于水精馏法生产重氧(18O)水的分离过程,在连续生产重氧(18O)水的同时,间歇副产低氘水,使一套同位素分离装置能同时制备二种同位素产品,开发了同位素水的综合制备的技术,提高了分离装置的有效利用率.     

Flosheet: Microcomputerized Flowsheeting/Simulation Program for Simulating Hydrogen Isotope Separation Processes

Abstract

Ontario Hydro has developed a comprehensive computer program, FLOSHEET, to simulate various hydrogen isotope separation processes, including water distillation and cryogenic distillation of elemental hydrogen isotopes. FLOSHEET was developed to assist in the operation and optimization of a Tritium Removal Facility Ontario Hydro is building at the Darlington Nuclear Generating Station. However, FLOSHEET is a general purpose simulator and allows the specification and simulation of complete process plants with various interconnected units. This paper discusses the development and features of FLOSHEET, as well as various simulation results which have emerged from the use of the program.     

丙烷脱氢反应气分离提纯丙烯和氢气过程严格模拟与能效评估

丙烷脱氢(PDH)是生产丙烯产品的重要方式之一,丙烷脱氢反应气组分复杂,为获得聚合级丙烯和纯度不小于99.90 mol/mol的氢气产品,在Aspen软件中对丙烷脱氢反应气分离和富氢尾气回收氢气的过程进行建模和模拟,分离过程包括醇胺脱碳、压缩深冷、脱乙烷、丙烯精馏和变压吸附单元。为了合理利用丙烯精馏塔的能量,对丙烯精馏塔进行能量集成,采用变压吸附工艺回收氢气并对分离过程工艺参数进行灵敏度分析及优化工艺参数,以提高经济性和能效。模拟结果可得到符合要求的丙烯和氢气产品,单位产品能耗分别为267.46 kg标准油/t丙烯产品,474.44 kg标准油/t氢气产品。     

Recovery of Tritium from Wastewater Generated by Decommissioning of Gas Cooled Reactors (GCR)

The recovery of tritium from wastewater generated by the decommissioning of a 166‐MWe GCR, Tokai‐1, nuclear reactor was evaluated. The dimensions of two tritium separation columns, water distillation process and hydrogen‐isotope exchange with hydrophobic Pt‐catalyst, were evaluated numerically under the assumptions that the recovery of tritium from the wastewater would be completed in five years and the wastewater after the recovery of tritium would be suitable for release into the environment. It was found that, in addition to lower steam, the column was smaller than that for the water distillation process. The hydrogen‐isotope exchange process was suitable for the treatment of wastewater, not only for a process design point of view but also for a reduction of energy consumption.     

Performance enhancement and energy reduction using hybrid cryogenic distillation networks for purification of natural gas with high CO2 content

A novel concept of hybrid cryogenic distillation network has been explored which maximizes the benefits of both desublimation or solid-vapor based separation as well as distillation or vapor-liquid equilibrium based separation during the separation of carbon dioxide from methane or natural gas. Process network synthesis has been performed for four case studies with high carbon dioxide (72 mole%) and medium carbon dioxide (50 mole%) natural gas feed streams. The benefits of optimal locations for cryogenic packed beds were investigated. A conventional cryogenic network consisting of multiple distillation columns with butane as additive for extractive distillation was also studied and presented in this paper. Process modeling of cryogenic distillation network with MESH equations was attempted using an integrated dual loop (C+3) convergence and the results were compared with Aspen Plus simulator for benchmarking. The prediction of solidification region was employed using experimental data from literature to avoid solidification regions in the column. The proposed hybrid cryogenic distillation network showed promising potential for energy and size reduction.     

化学交换精馏法分离同位素硼-10研究进展

综述了化学交换精馏法分离同位素硼-10的技术进展。在介绍化学交换精馏法分离同位素硼-10原理的基础上,分析了目前工业化过程分离同位素硼-10存在的问题,指出新的络合剂-硝基甲烷(CH3NO2)、丙酮(Acetone)、甲基异丁基酮(MIBK)、二异丁基酮(DIBK)等用于从三氟化硼分离硼-10具有更高的分离系数,形成的络合物具有更好的稳定性,其中CH3NO2是现有同位素硼-10分离工艺过程较为理想的替代络合剂。     

高沸点热敏体系精馏过程的研究进展

在精馏系统中，高沸点、热敏性物系分离存在物料受热温度高且时间长的问题，容易引起热敏性物质变质，一直是高效分离与提纯的难点。本文对高沸点热敏性物质精馏分离理论基础进行归纳，提出操作压力低和停留时间短的工艺要求。基于此，总结了分子蒸馏和真空精馏（包括真空蒸馏、真空分馏、真空间歇精馏）在高沸点热敏性物系分离中的优缺点及应用，发现分子蒸馏的真空度和分离程度较真空精馏高，但分离效率和工业化程度比真空精馏低。最后，文章指出，对于采用精馏分离高沸点热敏性体系仍需在新工艺和新设备等方面进行探索，以提高分离效率和降低分离能耗，便于实现工业规模应用。     

Design,optimization and controllability of an alternative process based on extractive distillation for an ethane–carbon dioxide mixture

Alternative configurations based on cryogenic extractive distillation were proposed and simulated by using Aspen Plus 7.0^® coupled to a multi-objective stochastic optimization procedure (differential evolution, DE). The evaluation of the performances of the proposed configurations was focused on the ethane–carbon dioxide azeotrope separation considering different liquefied hydrocarbon fractions as entrainers. The design alternatives were compared to the conventional chemical absorption system.The proposed sequences were simultaneously Pareto optimized by minimizing the total annual cost (TAC) and maximizing the acid gas removal. Complementary studies regarding the theoretical control properties, the thermodynamic efficiency and the greenhouse gases generation were conducted for several representative operating conditions obtained from the Pareto optimized fronts. The proposed cryogenic extractive distillation sequences realized the higher carbon dioxide removal together with the lower TAC compared to the conventional chemical absorption system.