基于二维传递模型的反应器网络综合

反应器网络综合的任务在于寻求适宜的反应器类型、尺寸及反应单元间的连接关系并确定各反应器的操作条件,其研究方法主要包括超级结构法和目标法,采用的基本单元均为一维理想模型。文中同时考虑传质、传热、流体流动以及反应动力学,通过偏微分方程描述轴向及径向上的温度、浓度分布,建立了二维反应器模型。基于该二维传递模型,采用状态空间构建反应器网络,并以年度总费用为目标函数评价反应器系统的经济性。最后,以提出的模型对环氧丙烷反应器网络进行了优化设计,实例验证了方法的有效性。     

内循环厌氧反应器气升循环系统水力模型探讨

针对现有IC反应器气升循环系统水力模型的不足之处,提出了更符合IC反应器内循环系统的水力模型,并对模型中的参数进行了计算机模拟及详细阐述。改进后的水力模型能更准确地反映IC反应器的结构及运行特性,对IC反应器的设计具有良好的指导作用。     

Preliminary design and simulation of a microstructured reactor for production of synthesis gas by steam methane reforming

The present study considers the potentials of the well-known production of syngas by steam methane reforming (SMR), by operation within microstructured reactors. The model of a microchannel reactor is developed, including very fast kinetic reaction rates on the coated catalytic walls of the reactor module. By varying the characteristic dimensions of the channels, and considering technical constraints on the design and operating conditions, the results demonstrate that the SMR reactor can be drastically miniaturized while maintaining its productivity without any additional pressure drop. Furthermore, by reducing the channel characteristic dimensions, it is possible to suppress heat and mass-transfer limitations enabling SMR reactor operation at thermodynamic equilibrium. A fast method for preliminary design of microstructured heat-exchanger reactors is developed, that enables to identify the optimal channels number and heat power needed to reach process specifications.     

基于CSTR的反应器网络综合目标策略法

根据构造目标函数法和超结构法的思想,采用基于CSTR的反应器网络模型,对Van-de-Vusse反应体系的流程结构进行了研究。通过建立数学模型并且优化可以看出,相对于超结构法以及三参数分布法,该方法所获得的流程结构更简洁有效。     

刮壁搅拌桨的最优设计

运用罚函数Ｇａｌｅｒｋｉｎ加权余量有限元数值算法模拟了Ｖｏｔａｔｏｒ、Ｃ＆Ｒ反应器和刮壁槽式釜中轴截面的流速和剪切分布。计算结果表明，Ｖｏｔａｔｏｒ，Ｃ＆Ｒ反应器中流动和剪切分布较刮壁槽式釜更有利于流体的混合和壁面的传热。对Ｃ＆Ｒ反应器，采用无间隙刮板，其传热和混合性能优于有间隙刮板。建议刮壁搅拌反应器的设计采用类似Ｖｏｔａｔｏｒ和Ｃ＆Ｒ反应器的环隙结构和无间隙的刮板形式。     

Modeling of a novel membrane reactor to integrate dehydrogenation of ethylbenzene to styrene with hydrogenation of nitrobenzene to aniline

The catalytic dehydrogenation of ethylbenzene to styrene is coupled with the catalytic hydrogenation of nitrobenzene to aniline in a simulated integrated reactor formed of two fixed beds separated by a hydrogen-selective membrane, where both hydrogen and heat are transferred across the surface of membrane tubes. A pseudo-homogeneous model of the two fixed beds predicts the performance of this novel configuration first proposed by Moustafa and Elnashaie [Simultaneous production of styrene and cyclohexane in an integrated membrane reactor. Journal of Membrane Science 178 (1), 171-184]. Both co-current and counter-current operating modes are investigated and the simulation results are compared with corresponding predictions for an industrial adiabatic fixed bed reactor operated at the same feed conditions. The conversion of ethylbenzene and the yield of styrene in the membrane reactor are predicted to exceed by a wide margin those in the industrial adiabatic fixed bed reactor. Aniline is also produced as an additional valuable product in a favorable manner, and autothermality is achieved within the reactor. The results suggest that coupling of these reactions could be feasible and beneficial. Experimental proof-of-concept is needed to establish the validity and safe operation of the novel reactor.     

A/DAT-IAT工艺设计中的若干问题

从设计的角度出发,详细论述了DAT-IAT工艺及前置厌氧反应器的DAT-IAT工艺(简称A/DAT-IAT)中沉淀/滗水时间、厌氧反应器体积、回流比、pH值、温度、滗水器选择及反应池数量等方面的问题。为使该工艺成功运行,建议沉淀和滗水时间分别为1h左右;厌氧反应器体积比为15%左右;内、外回流宜为200%和20%~30%;pH值为7～8;滗水设施采用旋转式滗水器。     

Simulation of a jet-assisted circulation jacketed batch reactor for polymerization of methylmethacrylate

A simulation of a five-liter, agitated, nonisothermal, jet-assisted circulation, jacketed methylmethacrylate polymerization batch reactor considering all the available physical-chemical properties and related correlations for agitation and heat transfer coefficients is presented. From the calculated cumulative radical population, the phenomena of early runaway, thermal ignition and gel effect ignition are identified. Variations of medium viscosity over the course of the polymerization reaction affect the performance of the agitator and the overall heat transfer coefficient. The simulation results indicate that much higher heat duties can be removed by this special equipment design than in the case of a conventional vessel design.     

40t/d PA6前聚合反应器设计简析

从设备与工艺两方面剖析了PA6生产前聚合反应器的设计。将反应器长径比例从原来的3:1改为10:1,并改进加热方式,优化结构设计,前聚合反应器设计为4段,各段间采用法兰连接,设计出生产能力40 t／d的前聚合反应器。     

Fischer–Tropsch synthesis: Overview of reactor development and future potentialities

An overview of the reactors utilized for the Fischer–Tropsch synthesis is considered during three time periods: discovery to 1945, 1945–1970, and 1970 to date. A brief outline of the scientific and engineering developments related to chemical reactor design for the same three periods is also presented. In general, the reactor developments outpaced the ability to utilize the scientific and engineering advances on the academic level. However, today it appears that the academic and industrial developments closely match each other in content and interests. Even so, the availability of reliable data from large-scale pilot plants and/or commercial operations remain available only to the organization developing the data.     

酶膜反应器控制系统的研制

提出了实现连续酶化反应的控制方案,利用单片机实时检测反应所需温度、pH值和体积,实现自动控制以满足连续酶化反应的要求。试验结果表明转化率和产物的产率均得到提高,该方法具有推广价值。     

平板型光催化反应器的研制及实验研究

在充分调研现有光反应器的基础上,结合污水处理系统的特点,自行设计制作出平板型光催化反应器.选取亚甲基兰、刚果红和有机磷农药乐果进行初步的室内、室外降解实验,进而提出系统还需优化之处,可供相关人员参考.     

化工反应器的开发

本文阐述了常见的釜式反应器以及固定床反应器与分离式反应器等反应器的基本原理、设计步骤及影响因素,并对其优缺点进行了比较,考虑到了反应器设计中应该注意的问题,并对反应器的设计前景提出了展望．     

Analysis and optimization of cross-flow reactors with distributed reactant feed and product removal

A systematic and general model was proposed for the simulation of cross-flow reactors with product removal and reactant feed policies. Six types of cross-flow reactors were analyzed for reversible series-parallel reaction systems and their optimal feed distributions were determined by maximizing the desired product yield at the outlet of the reactor. The performances of reactors with different types of feed policies were compared at their optimal operating conditions. For irreversible reaction systems with lower order in distributed reactant for the desired reaction than those for undesired reactions, a higher yield and selectivity of the desired product could be achieved with the reactors with staged feed than with conventional co-feed reactors and a sufficiently high residence time was required by staged feed reactors to significantly improve the desired product yields and selectivities over those obtained by a co-feed reactor. However, for reversible reaction systems, the desired product yield always reached a maximum value, and then dropped down as the residence time increased. In addition to the kinetic order and residence time requirements, the rate constants of the reactions involved have to fall within certain ranges for the distributed feed reactor to obtain a higher maximum yield than one-stage co-feed reactors. Optimally distributed feed reactors always give higher maximum product yields than evenly distributed reactors with the same number of feed points. However, the improvement of yields is not as great as that between co-feed reactors and evenly distributed reactors. On the other hand, for reaction systems with higher order with respect to the distributed reactant in the desired reaction than the undesired reactions, co-feed reactors always give higher yield than staged feed reactors.     

Comparison of two-phase and three-phase methanol synthesis processes

A comparison is made between the ICI (two-phase) methanol synthesis process and a three-phase slurry process based on a multi-stage agitated reactor. The process calculations are based on a complete reactor system consisting of the reactor itself, a recycling system and a gas-liquid separator. The basic kinetic and thermodynamic data were taken from previous studies carried out in our laboratory. The results show that both reactor systems produce comparable methanol yields under the same process conditions except for the reactor temperature. Carbon conversion to methanol values close to 100% can be achieved. The three-phase process is more efficient in terms of heat recovery and power consumption. This is primarily caused by the fact that the three-phase process generates high-pressure steam and the ICI two-phase process yields boiler feed water of 90°C. Furthermore, the pressure drop in the three-phase reactor is smaller than in the two-phase reactor, resulting in a smaller duty of the recycle compressor. However, for the present low energy prices, the annual financial savings, coupled with these energetic aspects, are not sufficient to compensate for the higher capital investment of the three-phase reactor system relative to the ICI two-phase reactor system. A relatively high natural gas price of US $4.1 per gigajoule is needed to reach the economical break-even point between the two processes. More active catalysts may be developed in the near future. Our results show that a relative increase in the catalyst activity by a factor of 1.5 or more (for both processes) will make the three-phase process of economic interest at a natural gas price of US $2.5 per gigajoule.     

环状非均相光催化反应器设计要素及应用研究

对目前使用很多的环状非均相光催化反应器的重要设计因素以及关键部件的选取进行了研究。依照得出的结论设计了一套简单实用的环状非均相光催化反应器,并进行了氨氮光催化降解实验以验证装置效果。结果证明,该设计装置降解效率较高,具有一定的推广前景。     

环氧树脂反应器的放大设计

简述环氧树脂反应原理与对反应器设计要求。详细介绍环氧树脂反应器从引进的１１８ｍ３放大到３６ｍ３的设计计算,结果表明其基本符合实际工况要求。     

平板型光催化反应器的研制及实验研究

在充分调研现有光反应器的基础上,结合污水处理系统的特点,自行设计制作出平板型光催化反应器;选取亚甲基兰、刚果红和有机磷农药乐果进行初步的室内、室外降解实验;进而提出系统还需优化之处;可供相关人员参考。     

APPLICATION OF ADAPTIVE PID CONTROL WITH GENETIC ALGORITHM TO A POLYMERIZATION REACTOR

This article describes the application of adaptive PID control with genetic algorithm (GA) to a jacketed batch polymerization reactor. This method was used to keep the polymerization reactor temperature at the desired optimal path, which was determined by the Hamiltonian maximum principle method. The reactor was simulated and the model equations of this jacketed polymerization reactor were solved by means of Runge-Kutta-Felthberg methods. A genetic algorithm can be a good solution for finding the optimum PID parameters because unlike other techniques it does not impose many limitations and it is simple. In this research, suitability of these parameters was checked by the integral absolute error (IAE) criterion. The control parameters in the PID algorithm were changed with time during the control of a polymerization reactor. It was seen that the genetic algorithm was able to tune the PID controller used in this system in terms of higher robustness and reliability by changing the parameters continuously.     

The reaction engineering of electrochemical cells—I. Axial packed bed electrodes

It is shown that the graphical method of solving the coupled equations for an endothermic reaction in a plug-flow, non-isothermal reactor can be extended to electrochemical reactions in three-dimensional electrodes. The method of solution is described and as a first example, it has been applied to a simple reversible reaction in an axial packed bed electrode. The sensitivity to various parameters has been examined. The method is ideally suited to computer-aided design procedures.