Design and optimization of a dividing wall column for debottlenecking of the acetic acid purification process

The dividing wall column (DWC) has gained increasing application in a variety of chemical processes because of its potentiality in energy and capital cost savings in multicomponent separations. The main objective in this work is investigation of its use for removing the bottleneck phenomenon within the column when increasing the throughput of an existing distillation process, particularly, the acetic acid (AA) purification process. Optimal column sequence design, involving both conventional and DWC, is considered. The internal recycle flow distribution around the dividing wall was investigated as a primary optimizing variable. Several column arrangements were analyzed to show that the DWC requires less investment and energy costs than conventional distillation, the Petlyuk column, or the prefractionator arrangement.     

煤气净化污水氨回收的流程进展及优化

煤气净化后,大量的氨进入煤气污水中,氨作为应用较为广泛的工业原料,这部分氨应加以回收,净化废水的同时获得无水液氨,创造经济效益。介绍了无水液氨工艺流程的优化过程。     

基于灵敏度分析的页岩气净化流程的模拟与优化

原料气中酸性气体与水等杂质的脱除净化是页岩气下游加工与利用的基础。应用化工流程模拟软件对页岩气脱酸与脱水流程进行模拟,旨为气体净化工业的实践提供理论与技术指导。在脱酸流程模拟中,采用灵敏度分析的方法讨论并优化了吸收剂再生进料位置、再生塔回流比等参数对脱酸流程的影响。脱水流程模拟中,提出了页岩气水含量与水露点的关联方法,为脱水标准的选取提供依据;采用汽提法解决了高浓度吸收剂的再生问题,使流程能够满足更高的脱水要求。     

生物甲烷膜分离提纯系统的设计与优化

以厌氧发酵生物气为原料生产压缩天然气是大规模利用生物质资源的重要途径。首先,在过程模拟软件UniSim Design中基于有限元方法建立了中空纤维膜的离散数值计算模型,适合于模拟渗透切割比非常高的生物甲烷膜分离过程。以单级聚酰亚胺膜分离系统为例研究了关键操作条件--膜的进料压力对处理能力、甲烷收率及压缩天然气生产单耗的影响。目前的评估体系下,提高进料压力有利于提高处理能力和甲烷回收率,而压缩天然气生产单耗在2.70 MPa时最低,为0.46 kW·h·m^-3压缩天然气。通过分析渗透气的甲烷浓度变化趋势,开发了一级二段气体膜分离系统,兼具流程简单、设备投资低、甲烷收率高、产值高的优点。以处理1000 m³·h^-1生物气为例,甲烷收率达95.0%,压缩天然气产量500 m³·h^-1。对应地,装置总投资为3.8×10⁶ CNY,年运行费用及设备折旧为1.5×10⁶ CNY,年经济效益（毛利）超过2.50×10⁶ CNY。     

丁二酸二甲酯精制工艺的设计与模拟分析

阐述了采用换热匹配利用加氢反应放热的丁二酸二甲酯精制工艺,该工艺基于对C4资源深度利用的顺酐酯化法生产丁二酸二甲酯技术。运用Aspen Plus软件对工艺流程进行了稳态模拟计算,工艺优化结果为:脱轻塔的适宜进料位置、优化的回流比和塔顶采出量分别为第5块板、7和19 kg/h;精制塔的适宜进料位置、优化的回流比和塔顶采出量分别为第11块板、3和764 kg/h;最终获得纯度(质量分数)高达99.9%的丁二酸二甲酯产品,其回收率为99.8%。另外运用Aspen Dynamics软件进一步考察了该工艺的动态性能,在进料流量和进料组成扰动情况下,控制系统可以有效调整装置操作条件使其在2—4 h内趋向平稳运行,精馏塔采用单端温度控制结构足以保证丁二酸二甲酯产品纯度和回收率。稳态和动态模拟结果为丁二酸二甲酯精制工艺的工业化设计和实际操作提供了借鉴。     

Design and optimization of an integrated process for the purification of propylene oxide and the separation of propylene glycol by-product

It is difficult to separate the methanol and hydrocarbons in the propylene oxide (PO) purification process due to their forming azeotrope. As for this, a novel PO separation process, in that the deionized water is employed as extractant and 1,2-propylene glycol (MPG) that is formed from the PO hydrolysis reaction is recovered, is presented in this work. The salient feature of this process is that both the non-catalyzed reactions of PO hydrolysis to form MPG and dipropylene glycol (DPG) are simultaneously considered and MPG by-product with high purity is obtained in virtue of the deionized water as reflux liquid and side take-off in MPG column. In addition, the ionic liquid (IL) extractant is screened through the conductor-like screening model for segment activity coefficient (COSMO-SAC) and the comparisons of separation efficiency between the IL and normal octane (nC₈) extractant for the separation of PO and 2-methylpentane are made. With the non-random two-liquid (NRTL) thermodynamic model, the simulation and optimization design for the full flow sheet are performed and the effects of the key operation parameters such as solvent ratio, theoretical stages, feeding stage etc. on separation efficiency are detailedly discussed. The results show that the mass purity and the mass yield of PO can be up to 99.99% and 99.0%, and the condenser duty, reboiler duty and PO loss in the process with IL extractant can be decreased by 69.66%, 30.21% and 78.86% compared to ones with nC₈. The total annual cost (TAC) calculation also suggests that the TAC would be significantly reduced if using IL in replace of nC₈ for the investigated process. The presented results would provide a useful guide for improving the quality of PO product and the economic efficiency of industrial plant.     

19F型肺炎链球菌菌种的复壮及其荚膜多糖纯化工艺的优化

目的开发复壮肺炎链球菌19F型(Sreptococcus pneumoniae serotype 19F,简称PN19F)菌种的方法,并优化其荚膜多糖的纯化工艺。方法配制PN19F菌种用液体扩增培养基和固体选择培养基,筛选出荚膜较厚的单菌落,比较复壮前后PN19F菌种的发酵培养情况、纯化后多糖收获量及多糖质量;将发酵液裂解后分别酸沉淀8、24和48 h,并经100 KD超滤纯化,再分别用乙醇法和冻干法制备精制多糖,比较其多糖收获量、组分检定结果、抗原活性、核磁共振图谱。结果两种培养基复壮前后的PN19F菌种,发酵收获菌液A600值及培养时间变化不大。纯化后多糖收获量分别为0. 2和0. 6 g/L,即复壮后多糖收率提高了195%。酸沉淀8、24 h后纯化的多糖质量合格,且24 h较8 h多糖收率高约38%,酸沉淀时间达48 h时,产率无明显变化,但多糖质量不合格。乙醇法和冻干法制备的精制多糖各项指标均合格,且无明显差异。结论应用制备的两种培养基复壮的PN19F菌种,可明显提高荚膜多糖产量。PN19F菌种的酸沉淀时间不超过24 h,乙醇法和冻干法均可用于精制多糖制备。     

应用Aspen Batch对年产25吨鲁拉西酮原料药工艺设计优化

采取专利CN 102863437 A的工艺,设计间歇工艺过程,将Aspen Batch Process Developer软件应用于盐酸鲁拉西酮原料药车间设计的全流程模拟和优化。间歇操作具有显著的优势：生产灵活,同一设备可生产不同产品,可根据市场需要调节生产能力及变更产品。适合于小批量,高收益的精细化学品。过去的四十年里,使用计算机对化工连续化生产进行模拟和设计已经十分普及。制药工业与传统化工最大的区别是生产过程多采用间歇法操作。目前世界上应用于化工间歇生产的计算机软件有BATCHES、gPROMS和Aspen Batch Process Developer。本文所用版本为Aspen Tech V8.6,以年产25t盐酸鲁拉西酮原料药车间为例,对车间进行全流程模拟及优化。整个设计贯彻质量源于设计理念,运用元葱模型,将盐酸鲁拉西酮的生产工艺分为磺化、氨解、氢化、缩合、成盐、精烘包等6个模块。     

Discovery of novel zeolites for natural gas purification through combined material screening and process optimization

An efficient computational screening approach is proposed to select the most cost‐effective materials and adsorption process conditions for CH₄/CO₂ separation. The method identifies eight novel zeolites for removing CO₂ from natural gas, coalbed methane, shale gas, enhanced oil recovery gas, biogas, and landfill gas sources. The separation cost is minimized through hierarchical material screening combined with rigorous process modeling and optimization. Minimum purity and recovery constraints of 97 and 95%, respectively, are introduced to meet natural gas pipeline specifications and minimize losses. The top zeolite, WEI, can recover methane as economically as $0.15/MMBTU from natural gas with 5% CO₂ to $1.44/MMBTU from natural gas with 50% CO₂, showing the potential for developing natural gas reservoirs with higher CO₂ content. The necessity of a combined material selection and process optimization approach is demonstrated by the lack of clear correlation between cost and material‐centric metrics such as adsorption selectivity. © 2014 American Institute of Chemical Engineers AIChE J, 60: 1767–1785, 2014     

Design and cost optimization of a hot fuel gas desulfurization process

A high temperature gas desulfurization process is proposed that effectively uses the iron oxides in the waste ashes from coal gasifiers to react with and sorb the H₂S, COS, and CS₂, in coal-derived fuels. The process is carried out at 1033 K and 2.22 MPa in packed bed reactors. Sulfided ash sorbents may be repeatedly regenerated to produce a 30/70 molar mixture of S₂ and SO₂, suitable for complete reduction to elemental sulfur or sulfuric acid manufacture.An optimization theory predicts the use of very shallow bed reactors, packed to 0.61 meters, operating in a cyclic sequence where the onstream time is only 0.37 hours. This markedly reduces the capital and operating costs.A plant treating 1.22 MM SCMH of 0.63 mole percent H₂S ladened fuel gas is estimated to have a 1981 cost of $7.638 million and an annual operating cost of $5.229 million. A modular plant for recovery of byproduct SO₂, as H₂SO₄ is estimated to cost an additional $11.38 million but shows an annual before-tax profit of $10.46 million based upon a selling price of $80/Ton for the acid. This large profit reflects the value of the by-product SO₂.     

高黏度聚合MDI新工艺的设计及运行优化

简述了目前生产高黏度聚合MDI(多亚甲基多苯基多异氰酸酯)的3种生产工艺,为解决现有工艺中存在的填料污染、纯MDI质量差等问题,文中结合现有工艺的特点设计了短程蒸发+分离塔组合新工艺,对新工艺进行了物料平衡模拟以及短程蒸发器关键参数计算,并将短程蒸发+分离塔新工艺进行了工业化实施。为实现新工艺的长周期稳定运行,开展了短程蒸发+分离塔新工艺下的刮片材质优化、防飞溅挡板优化、操作温度优化等。通过设备及工艺条件优化,短程蒸发+分离塔新工艺工业化装置实现6个月以上的长周期运转,同时中间体M中重组分质量分数、PM中二聚体质量分数都较现有工艺大大降低,新工艺生产的高黏度聚合MDI的低温稳定性、长期储存稳定性均优于分离塔工艺,高黏度聚合MDI产品质量明显提升。文中通过工艺流程设计、模拟计算、工业化实施、装置运行优化等,将短程蒸发+分离塔新工艺成功地用于生产高黏度聚合MDI。     

车用膨胀减震胶的设计及工艺优化方案

某车型在试生产过程中,车辆下线进行开关门测试时,车门钣金存在不同程度异响的现象。经过对车门进行拆解分析,找到了导致车门钣金异响的主要因素,研究了车用膨胀减震胶参数及施胶工艺对车门钣金异响的影响,并通过设计优化与试验验证解决了车门钣金异响问题。同时,提出了车用膨胀减震胶的正向设计开发思路及注意事项。     

盐酸索他洛尔的合成及工艺改进

以对硝基苯乙酮为原料经过还原，酰化，溴化，综合及还原5步合成盐酸索他洛尔，经工艺改进，收率有较大的提高，改进的制备方法使总收率达到33.9%，降低了生产成本，更适合工业化生产。     

Design and optimization of a new photocatalytic reactor with immobilized ZnO for water purification

The objectives of this work were to study the degradation of the niflumic acid (NIF) with a new solar photocatalytic reactor using immobilized ZnO. The residence time distribution and the reactor efficiency for the NIF removal were studied. Two models for Retention Time Distribution (RTD) have been summarized and compared with the experimental data. Effects on the photocatalytic degradation process owing to various operating parameters conditions were also studied in continue flow. The repetitive operation performance indicates the good reproducibility of the new reactor for NIF degradation. Concerning the energy, the reactor was designed to ensure its energy autonomy through solar energy.     

吡啶盐酸盐的合成工艺

介绍了吡啶盐酸盐的两种合成工艺,哟啶和盐酸的液液合成法及吡啶和氯化氢气体的气液合成法。液液合成法收率８５％,气液合成法收率９２％。     

乙烯深冷分离中变温冷却过程制冷系统的设计与优化

根据乙烯装置中的用冷需求,将乙烯装置的深冷分离过程分为变温冷却过程和定温冷凝过程,变温冷却过程指的是裂解气的预冷过程,定温冷凝过程指的是乙烯装置中各塔塔顶冷凝器中的换热;分析了乙烯-丙烯复叠制冷系统的换热集成曲线,可知在裂解气的预冷阶段,冷热物流换热温差大。提出一种组合制冷系统,它集成了纯工质复叠制冷和混合冷剂制冷,其中的多元混合冷剂制冷系统为乙烯深冷分离的变温换热过程提供冷量。并用Aspen Plus软件对混合冷剂系统进行建模,使用遗传算法优化,优化结果表明在替代原制冷系统6895.5 kW冷量负荷的情况下,功耗降低521.6 kW,节能14.7%。     

单体工序净化工艺的改进

通过对单体工序净化工艺的改进,加装了水洗塔废水闭路循环系统,脱酸塔塔盘由石墨改为胶木材质,保证了合成气净化装置长周期稳定运行,避免了水洗塔外排酸性水,节约了水资源,还可回收高浓度副产盐酸,减少了氯乙烯损失,全年可获效益178.86万元。     

盐水精制过程分析

通过对离子膜进槽盐水中不纯物的来源及危害的分析，提出优化盐水精制的方法，以期提高盐水质量。     

间苯二甲腈结晶精制工艺

气相氨氧化法生产间苯二甲腈存在产品纯度低、废水排放量大等问题。文中在实验研究的基础上,从溶剂的溶解特性及结晶提纯效果出发,筛选出了以乙醇和水的复合溶剂为间苯二甲腈的结晶溶剂,通过加热溶解、降温结晶、离心过滤及溶剂回收等工艺过程,精制后的间苯二甲腈纯度(质量分数)可达99.5%以上,满足了国际市场的要求,废水排放量也由每1 000 kg产品40 000 kg降至1 100 kg。     

Design of experiments for statistical modeling and multi-response optimization of nickel electroplating process

The central composite experimental design and response surface methodology have been employed for statistical modeling and analysis of the results dealing with nickel electroplating process. The empirical models developed in terms of design variables (current density J (A/dm²), temperature T (°C) and pH) have been found statistically adequate to describe the process responses, i.e. cathode efficiency Y (%), coating thickness U (μm), brightness V (%) and hardness W (HV). The graphical representations consisted of 2D contour plots and 3D surface plots have been used for exploring and analysis of response surfaces in order to identify the main, quadratic and interaction effects. The multi-response optimization of nickel electroplating process has been carried out by means of desirability function approach. To this end, a genetic algorithm has been used for mathematical optimization of the multi-response problem. The optimization algorithm has conducted to a set of equivalent solutions named Pareto optimal set. The confirmation runs have been employed in order to make a decision about the optimal solution approved by experiment. Thus, the optimum conditions of nickel electroplating has been defined in this work as J* = 5.35 (A/dm²), T* = 33.44 (°C) and pH* = 6.22 and respectively the responses confirmed by experiment were Y = 79.12 ± 0.18 (%), U = 52.77 ± 0.48 (μm), V = 26.12 ± 0.45 (%) and W = 371.6 ± 1.77 (HV). In such conditions the quality of nickel electroplating deposit was the best one in accordance with experimental results.