三元混合物分壁塔精馏分离的研究

提出了甲醇-乙醇-正丙醇三元混合物分壁塔精馏分离的新工艺。通过模拟和灵敏度分析,考察了分壁塔的进料位置、隔板位置、液体分配比、回流比等工艺参数对分离效果的影响,确定了分壁塔的最佳操作条件,并对分壁塔的能耗进行了分析。结果表明,单个分壁塔能达到常规三元混合物分离的要求,并且比常规精馏流程的分离过程节能约30%。     

贵冶三期工程硫酸一系列洗涤塔的改造

介绍了贵溪冶炼厂硫酸一系列全玻璃钢制填料塔的技术改造,换用管式与槽式结合的分酸装置,分酸点密度为27.3点/m^2;塔内增设支撑圈、加强圈,加厚塔壁对塔体进行加固.改造后,填料塔运行情况良好.     

分壁精馏塔分离苯/甲苯/二甲苯的模拟工艺研究

分壁精馏塔（简称分壁塔）在节能和节约投资方面都有很大的优势和潜力,因此近几年来人们对它的深入研究也越来越多。以等比例的苯、甲苯和二甲苯为原料,通过模拟工艺流程,研究分析了分壁塔的进料位置、隔板位置、回流比、侧线采出位置以及液汽相分流比与能耗、组分纯度的关系。研究结论显示,分壁塔的最适宜液相分流比和汽相分流比分别为0.65和0.45,与常规精馏塔相比,分壁塔分离所得的苯、甲苯和二甲苯的纯度高,冷凝负荷和热负荷分别比常规精馏塔降低31.066 9%和34.167 5%。     

同时生产重整及异构化反应进料的分馏塔的优化设计

通过对分壁塔和常规两塔流程分离重整原料油的分析比较。通过模拟与计算,在保证分离效果和产品质量基本一致的前提下,从能耗、占地、投资等方面进行了对比,结果表明,分壁塔流程能耗降低15.1%,占地面积减少40.4%,投资节能27.2%。     

比较双进料和双侧线采出策略对隔壁塔操作与控制的影响

针对3种常见的隔壁塔控制结构,即3点控制结构、控侧线产品不纯物比例的4点控制结构和控预分馏塔顶部重组分纯度的4点控制结构,分别从开环分析和闭环分析2方面比较了双进料和双侧线采出策略对隔壁塔操作与控制的影响。结果显示,在3种控制结构下,双侧线采出策略均更有利于隔壁塔的操作与控制。     

分壁塔分离萘及其加氢产物的稳态研究

为高效分离萘及其加氢产物,设计了具有节能潜力的分壁塔并分析了分离状态和分离过程。首先,对分离过程进行简捷计算,得到各个区域所需最小蒸汽量;再用Aspen Plus软件建立分壁塔四塔模型,并对四塔模型以TAC为目标函数进行优化得到最佳设计和操作参数;最后对分壁塔分离萘及其加氢产物的分离状态进行分析。结果表明,隔板左右两侧温差较大,最高达13.8 K;反式十氢萘和萘在全塔中不存在返混,而顺式十氢萘和四氢萘在预分离段的返混不可避免,但在主塔中不存在返混;可通过分液比控制侧线中杂质比;侧线中杂质易分离时,分液比对侧线产品的影响更敏感。     

全溢流型阳极保护不锈钢分酸器设计参数选择

介绍了全溢流型阳极保护不锈钢管槽式分酸器的结构和设计特点。重点探讨了分酸点密度、分酸点排列、落酸管和降液管规格、酸液初始分布、分酸器安装等分酸器设计、制造重要参数选用问题,设计推荐分酸点密度35～42点/m~2,优先选择分酸点三角形排列方式,周边分酸点距塔壁的距离取100～180mm,分酸器安装时要求各槽体水平度在5mm以内,分酸器安装占位高度为800～1200mm,从而确保分酸器分酸均匀、稳定,避免出现短流、液泛等不良情况。     

基于优化总投资的分壁精馏塔分离BTX工业原料模拟分析

节能减排是当今石化领域的研究热点之一。作为典型的过程强化设备,分壁精馏塔(DWC)具有明显的节能和节约设备投资的优势。本文首先对两塔分离苯–甲苯–二甲苯混合物(BTX)工业原料的过程进行了模拟,在此基础上对使用分壁精馏塔进行分离的过程进行了模拟及优化,最后对比两塔流程和DWC分离工业BTX原料的结果表明,分壁精馏塔较常规的两塔分离序列节能和节约设备投资效果明显,DWC较两塔流程节能36%,全塔总投资下降32%。     

阳极保护槽管式不锈钢分酸器的应用

硫酸生产干吸效率与分酸器的性能即分酸效果密切相关。目前，常用分酸器主要有管式和槽式两种，所用材质已由早期的普通铸铁发展到低铬铸铁、合金铸铁，分酸点密度一般小于20点／m^2。常用分酸器的分酸效果不够理想，主要原因是：铸铁的铸造精度低，开孔数量有限；安装过程中水平度有偏差；沿塔壁有分酸“盲区”。分酸器分酸效果     

内压缩流程空分的换热与精馏研究

分析和讨论了内压缩空分设备的氧氮两组分、氧氮氩三组分及氧氩两组分和氮氩两组分的相平衡,精馏部分的上塔、下塔、粗氩塔、精氩塔的精馏以及高压主换热器、低压主换热器、过冷器及主冷凝蒸发器等换热设备。希望能促进空气分离设备在理论方面的发展。     

Experimental study on pressure drops in a dividing wall distillation column

Previous studies in the fields of process design and process control [1] have shown the potential benefits that can be achieved through the implementation of thermally coupled distillation sequences, in particular, the dividing wall distillation column. The dividing wall distillation column meets important goals of process intensification, including energy savings, reduction in carbon dioxide emissions and miniaturization. In this paper, an experimental study on the hydrodynamic behavior of a dividing wall distillation column is presented. Several different values for gas and liquid velocities were tested in order to measure pressure drops and identify operational regions; the air/water system was used as the basis for the experimental setup. Results regarding pressure drops (fitted to the model of Stichlmair et al.) provide operational limits for the operation of the packed dividing wall distillation column. According to the results, the experimental dividing wall column can be operated at turbulent regime that is associated to proper mass transfer.     

Reactive dividing wall column for hydrolysis of methyl acetate:Design and control☆

Reactive distillation and dividing wall column distillation are two kinds of effective separation technologies, and their integrated configuration, reactive dividing wall column (RDWC), presents attractive advantages. In this study, the rigorous simulation of RDWC for methyl acetate hydrolysis is performed, and sensitivity analysis is conducted to obtain the minimum reboiler duty. Then a comparison is made between the conventional process and RDWC process, and it shows that 20.1%energy savings can be achieved by RDWC process. In addition, the dynamic characteristic of RDWC is studied and an effective control strategy is proposed. The simple PI control scheme with three temperature loops can obtain reasonable control performance and maintain products at de-sired purities. It is proved that this RDWC process is an energy efficiency alternative with good controllability. ? 2016 The Chemical Industry and Engineering Society of China, and Chemical Industry Press. Al rights reserved.     

Implementation and Operation of a Dividing‐Wall Distillation Column

The design and construction of a prototype of a dividing‐wall distillation column was possible by integrating previous knowledge in process intensification, energy savings, theoretical control properties, and closed‐loop dynamics of thermally coupled distillation sequences. In order to achieve the predicted energy savings for this class of complex distillation column, a dividing wall and a side tank were implemented in order to manipulate the internal flows associated with energy consumption. The reaction between ethanol and acetic acid was conducted within the prototype, and the experimental results indicate that a heterogeneous mixture of ethyl acetate and water is obtained as the top product. The temperature profile measured during the experimental run can be used for controlling the batch distillation column in cyclic operation mode.     

渗透汽化-隔壁塔精馏耦合初步分离费托合成水的过程研究

费托合成水中含有醇、酮、酸等多种高附加值含氧有机物可提取出来作为高附加值产品,但由于费托合成水处量大,共沸体系复杂,通常需要首先对其进行初步分离。设计了直接两塔精馏、渗透汽化-两塔精馏、直接隔壁塔精馏、渗透汽化-隔壁塔精馏四种可供选择的初步分离工艺。根据渗透汽化实验数据在Aspen Plus中构建渗透汽化过程模型并进行模拟,结合灵敏度分析得到精馏过程的最佳工艺参数和模拟结果,并对四种工艺的能耗和有效能损失进行对比。结果表明,渗透汽化-隔壁塔精馏工艺具有明显的节能优势,其能耗较直接两塔精馏可降低15.85%,有效能损失降低45.74%。经渗透汽化膜预浓缩后,溶液的浓度可进入隔壁塔的适宜分离浓度区间,以充分发挥隔壁塔优势。由于渗透汽化所需能量可由余热等低品位热源提供,在余热充足的煤化工领域中可显著降低有效能损失。对于该过程而言,当渗透汽化膜价格低于438元/m²时,渗透汽化-隔壁塔精馏耦合工艺将会表现出较高的经济性。     

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.     

Energy conserving effects of dividing wall column☆

The energy-conserving performance of dividing wal column (DWC) is discussed in this paper. The heat transfer through the dividing wall is considered and the results are compared with that of common heat insulation dividing wall column (HIDWC). Based on the thermodynamic analysis of heat transfer dividing wall column (HTDWC) and HIDWC, both computer simulation and experiments are employed to analyze the energy-conserving situation. Mixtures of n-hexane, n-heptane and n-octane are chosen as the example for separation. The results show that the energy consumption of HTDWC is 50.3%less than that of conventional distillation column, while it is 46.4% less than that of HIDWC. It indicates that DWC is efficient on separating three-component mixtures and HTDWC can save more energy than HIDWC. Thus it is necessary to consider the heat transfer while applying DWC to industry.     

萃取精馏分离苯/环己烷共沸体系的控制策略

将常规萃取精馏、差压热耦合萃取精馏以及隔壁塔萃取精馏技术应用于以糠醛为萃取剂的苯和环己烷共沸物分离过程。在稳态模型的基础上,利用Aspen Dynamics软件进行控制研究,对三工艺流程提出了若干控制策略。结果表明,对于常规萃取精馏过程,再沸器热负荷与进料量比值控制结构在降低控制过程超调量方面表现出明显优势;对于差压热耦合萃取精馏过程,带有压力-补偿控温策略的方案控制效果更佳;而对于隔壁塔,则选择了无隔板下方气液分离比控制的结构来作为较优的控制策略。     

隔壁塔流程模拟及节能效益的研究

隔壁塔技术是一种效果优良的过程强化与精馏节能技术。具有特殊结构的隔壁塔相比常规精馏塔具有较高的热力学效率。对于相同的分离任务,隔壁塔所需的能耗较低,同时隔壁塔技术的应用也降低了设备数量和投资。文中通过对隔壁塔内部结构的讨论和热力学有效能转化的分析,阐释了隔壁塔的节能原理;并以粗苯精制流程中甲苯-二甲苯-重苯的分离为例,在三组元精馏流程的分析之上设计了2套精馏流程方案,对其进行了严格计算和优化,相比于传统的顺序分离双塔流程,隔壁塔可节省能耗41.5%,同时减少了设备的数目和投资。     

隔壁式空分精馏塔应用性能研究

为了降低空气低温分离过程的设备投资和能耗,在分析空分体系的热力学性质及流程特点的基础上,提出了一种新型的隔壁式空分精馏塔流程。应用Aspen Plus模拟软件,对空气分离的传统流程和隔壁塔流程进行了模拟对比,考察了隔壁式空分精馏塔各结构参数与操作参数对其年总成本的影响,并分析比较了空分传统流程和隔壁式空分精馏塔流程的热力学效率。结果表明,隔壁式空分精馏塔的建模合理可行,通过年总成本优化得到了该隔壁塔的最优结构参数与操作参数,分别为:液氧流量为3 kmol/h,气相分配比(体积比)为0.05,精馏段理论板数为33,侧线精馏段理论板数为30,公共提馏段理论板数为22。与传统空分流程相比,隔壁式空分精馏塔流程的有效能损失降低并且在热力学效率方面高出4.7%。     

Investigation of the operability for four-product dividing wall column with two partition walls

For separating some specific four component mixtures into four products, the four-product dividing wall column (FPDWC) with two partition walls can provide the same utility consumption with the extended Petlyuk configuration, although with structure simplicity. However, the reluctance to implement this kind of four product dividing wall column industrially also consists in the two uncontrollable vapor splits associated with it. The vapor split ratios are set at the design stage and might not be the optimal value for changed feed composition, thus minimum energy consumption could not be ensured. In the present work, a sequential iterative optimization approach was initially employed to determine the parameters of cost-effective FPDWC. Then the effect of maintaining the vapor split ratios at their nominal value on the energy penalty was investigated for the FPDWC with two partition walls, in case of feed composition disturbance. The result shows that no more than + 2% above the optimal energy requirements could be ensured for 20% feed composition disturbances, which is encouraging for industrial implementation.