催化裂化提升管反应器中颗粒聚团裂化反应的数值模拟

Behavior of catalytic cracking reactions of particle cluster in fluid catalytic cracking (FCC) riser reactors was numerically analyzed using a four-lump mathematical model. Effects of the cluster porosity, inlet gas velocity and temperature, and coke deposition on cracking reactions of the cluster were investigated. Distributions of temperature, gases, and gasoline from both catalyst particle cluster and an isolated catalyst particle are presented. The reaction rates from vacuum gas oil (VGO) to gasoline, gas and coke of individual particle in the cluster are higher than those of the isolated particle, but it reverses for the reaction rates from gasoline to gas and coke. Less gasoline is produced by particle clustering. Simulated results show that the produced mass fluxes of gas and gasoline increase with the operating temperature and molar concentration of VGO, and decrease due to the formation of coke.     

液相合成甲醇催化剂活性的研究

The effects of reduction procedure, reaction temperature and composition of feed gas on the activity of a CuO-ZnO-Al2O3 catalyst for liquid phase methanol synthesis were studied. An optimized procedure different from conventional ones was developed to obtain higher activity and better stability of the catalyst. Both CO and CO2 in the feed gas were found to be necessary to maintain the activity of catalyst in the synthesis process. Reaction temperature was limited up to 523K, otherwise the catalyst will be deactivated rapidly. Experimental results show that the catalyst deactivation is caused by sintering and fouling, and the effects of CO and CO2 on the catalyst activity are also investigated. The experimental results indicate that the formation of water in the methanol synthesis is negligible when the feed gas contains both CO and CO2. The mechanism for liquid-phase methanol synthesis was discussed and it differed slightly from that for gas-phase synthesis.     

苯氯化侧反应精馏过程的系统设计与控制(英文)

The distillation column with side reactors (SRC) can overcome the temperature/pressure mismatch in the traditional reactive distillation, the column operates at temperature/pressure favorable for vapor-liquid separation, while the reactors operate at temperatures/pressures favorable for reaction kinetics. According to the smooth operation and automatic control problem of the distillation column with side reactors (SRC), the design, simulation calculation and dynamic control of the SCR process for chlorobenzene production are discussed in the paper. Firstly, the mechanism models, the integrated structure optimal design and process simulation systems are established, respectively. And then multivariable control schemes are designed, the controllability of SRC process based on the optimal steady-state integrated structure is explored. The dynamic response performances of closed-loop system against several disturbances are discussed to verify the effectiveness of control schemes for the SRC process. The simulating results show that the control structure using conventional control strategies can effectively overcome feeding disturbances in a specific range.     

Microchannel reactors for Fischer-Tropsch synthesis: Experimental investigation and mathematical modeling

The Fischer-Tropsch synthesis is a significant technology for converting coal, natural gas, and biomass into synthetic fuels. In recent years, the use of microchannel reactors for the Fischer-Tropsch synthesis has attracted significant attention. Fischer-Tropsch synthesis experiments were carried out in a microchannel reactor and the influences of reaction conditions on the experimental results were investigated in this study. Based on the experimental data, a dynamic multi-component pseudo-homo...     

高岭土微球原位合成SAPO-34分子筛及其在流化床甲醇/二甲醚制烯烃过程中的应用(英文)

SAPO-34 zeolite is considered to be an effective catalyst for methanol or dimethyl ether conversion to olefins. In this study, we developed the in situ synthesis technology to prepare SAPO-34 zeolite in kaolin microspheres as a catalyst for fluidized methanol or dimethyl ether to olefins process. The silicoaluminophosphate zeolite was first time reported to be synthesized in kaolin microspheres. The SAPO-34 content of synthesized catalyst was about 22% as measured by three different quantitative methods (micropore area, X-ray fluorescence and energy dispersive spectroscopy element analysis). Most of the SAPO-34 zeolites were in nanoscale size and distributed uniformly inside the spheres. The catalytic performance was evaluated in fixed bed and fluidized bed reactors. Compared with the conventional spray-dry catalyst, SAPO/kaolin catalyst showed superior catalytic activities, better olefin selectivities (up to 94%, exclusive coke), and very good hydrothermal stability. The in situ synthesis of SAPO-34 in kaolin microspheres is a facile and economically feasible way to prepare more effective catalyst for fluidized MTO/DTO (methanol to olefins/dimethyl ether to olefins) process.     

超临界流体萃取制备脱沥青油与沥青微粒

A continuous three-stage supercritical fluid extraction (SFE) process with a capacity of 1.0kg.h^-1 was setup to extract petroleum residue by pentane to obtain more oil for further upgrading. A discharging system integrated to the bottom of the extractor was used to recover solvent as gas while asphalt was obtained as fine particles. The influence of operating conditions on the yield and quality of extracts, i.e., deasphalted oil (DAO) and resin, was studied in the range of temperature 150-220℃, pressure of 4.0-6.0 MPa and the mass ratio of solvent to oil feed (S/O) 2.5-5.0. The particle size distribution, apparent forms and the packing density, which vary with operating pressure, were measured. The particle structures were observed by SEM as well. With the modification to conventional processes, furnace can be eliminated for solvent recovery from asphalt phase, so as to reduce energy consumption.     

一种新的利用LNG冷能的回收油田伴生气凝液的工艺

A novel process to recovery natural gas liquids from oil field associated gas with liquefied natural gas (LNG)cryogenic energy utilization is proposed.Compared to the current electric refrigeration process,the proposed process uses the cryogenic energy of LNG and saves 62.6%of electricity.The proposed process recovers ethane, liquid petroleum gas(propane and butane)and heavier hydrocarbons,with total recovery rate of natural gas liquids up to 96.8%.In this paper,exergy analysis and the energy utilization diagram method(EUD)are used to assess the new process and identify the key operation units with large exergy loss.The results show that exergy efficiency of the new process is 44.3%.Compared to the electric refrigeration process,exergy efficiency of the new process is improved by 16%.The proposed process has been applied and implemented in a conceptual design scheme of the cryogenic energy utilization for a 300 million tons/yr LNG receiving terminal in a northern Chinese harbor.     

Recent developments on catalytic membrane for gas cleaning

Catalytic membrane, a novel membrane separation technology that combines catalysis and separation, exhibits significant potential in gas purification such as formaldehyde, toluene and nitrogen oxides(NO_x). The catalytic membrane can remove solid particles through membrane separation and degrade gaseous pollutants to clean gas via a catalytic reaction to achieve green emissions. In this review, we discussed the recent developments of catalytic membranes from two aspects: preparation of catalytic membrane and its application in gas cleaning.Catalytic membranes are divided into organic catalytic membranes and inorganic catalytic membranes depending on the substrate materials. The organic catalytic membranes which are used for low temperature operation(less than 300 °C) are prepared by modifying the polymers or doping catalytic components into the polymers through coating, grafting, or in situ growth of catalysts on polymeric membrane. Inorganic catalytic membranes are used at higher temperature(higher than 500 °C). The catalyst and inorganic membrane can be integrated through conventional deposition methods, such as chemical(physical) vapor deposition and wet chemical deposition. The application progress of catalytic membrane is focused on purifying indoor air and industrial exhaust to remove formaldehyde, toluene, NO_x and PM2.5, which are also summarized. Perspectives on the future developments of the catalytic membranes are provided in terms of material manufacturing and process optimization.     

天然气基乙炔工艺 分析与改进

This article presents an acetylene production process by partial oxidation/combustion of natural gas. The thermodynamic performance and exergy analysis in the process are investigated using the flow-sheeting program Aspen Plus. The results indicate that the most important destruction of exergy is found to occur in the reactor and water quenching scrubber, amounting to 8.23% and 10.39%, respectively, of the entire system. Based on the results of thermodynamic and exergy analysis, the acetylene reactor has been retrofitted. The improvement ratios of molar 02 to CH4 and molar CO to CN4 are 0.65 and 0.20, respectively. An improvement of the acetylene production system is proposed. Adopting the improvement operation conditions and using oil to realize the reaction heat recovery, the feedstock of natural gas is reduced by 9.88% and the exergy loss in the retrofitting process is decreased by 19.71% compared to the original process.     

Catalytic kinetics of dimethyl ether one-step synthesis over CeO_2–CaO–Pd/HZSM-5 catalyst in sulfur-containing syngas process

CeO_2–CaO–Pd/HZSM-5 catalyst was prepared for the dimethyl ether(DME) one-step synthesis in a continuous fixed-bed micro-reactor from the sulfur-containing syngas. The catalytic stability over hybrid catalyst of CeO_2–CaO–Pd/HZSM-5 was investigated to ensure that the kinetics experimental results were not significantly influenced by induction period and catalytic deactivation. A large number of kinetic data points(40 sets) were obtained over a range of temperature(240–300 °C), pressure(3–4 MPa), gas hourly space velocity(GHSV)(2000–3000 L·kg~(-1)·h~(-1)) and H_2/CO mole ratio(2–3). Kinetic model for the methanol synthesis reaction and the dehydration of methanol were obtained separately according to reaction mechanism and Langmuir–Hinshelwood mechanism. Regression parameters were investigated by the method combining the simplex method and Runge–Kutta method. The model calculations were in appropriate accordance with the experimental data.     

国内外甲烷催化部分氧化技术进展

介绍了国内外甲烷催化部分氧化制合成气技术的研究进展。主要工艺包括固定床工艺、流化床工艺和陶瓷膜工艺。此外，在反应器方面，还对两项最新专利技术进行了讨论。最后，提出了甲烷催化部分氧化制合成气技术的发展趋势，为我国在天然气利用方面的技术开发提供了参考和依据。     

Reaktionstechnik bei industriellen Hochdruckverfahren

Reaction engineering in industrial high-pressure processes . The essential task of industrial chemistry is to transform cheap raw materials into high-quality materials and substances economically. From the very beginning, the chemical industry has used the energy sources coal, oil, and gas as the starting point for synthesis. These substances are introduced into the product line through high-pressure reactions. Joint developments in catalytic chemistry reaction kinetics, and plant design have permitted construction and operation of high-capacity, high-pressure plants at remote sites, where coal, oil, and gas are won. Industrial high-pressure chemistry is thus capable of transforming in situ raw materials that could be used otherwise into high-value products worth transporting to energy-poor regions and whose distribution is secured. The second part of this paper considers the technical limits of pumps, compressors, and high-pressure reactors. Approximate estimates of investment costs as a function of the pressure as process parameter are given for a high-pressure process step. Aspects to be taken into consideration during design, construction, and installation of factory-built high-pressure reactors are considered in condensed form in the last part.     

低压气固相固定床催化反应器优化设计系统

介绍用C＋＋Builder5.0编制的低压气固相固定床催化反应器优化设计系统（Reactor4.0）的功能和物热平衡联立求解方法。经多次验证，本系统可用于单段或多段气固相低压催化反应器的工艺参数和设计尺寸设计，结果可靠。     

Development and analysis of heterogeneous catalytic processes and reactors

A retrospective review and a review of the current state are given for the problem of the development and analysis of heterogeneous catalytic processes and reactors. Advanced approaches to the study of kinetics and the engineering design of catalytic reactions are discussed. The advantages and drawbacks of the main types and structures of industrial catalytic reactors are demonstrated by the examples of present-day catalytic processes and reactors for basic organic and petrochemical synthesis. The operation of several industrial catalytic reactors is analyzed in order to clarify the causes of deterioration of design performance and/or to find ways for the process intensification in operating plants.     

Calcination of Co-Based Fischer–Tropsch Synthesis Catalysts

The calcination of Co-based slurry-phase Fischer–Tropsch synthesis catalysts was investigated. Fischer–Tropsch synthesis is part of the gas-to-liquids (GTL) process that produces gas oil and naphtha from natural gas. For the GTL process, the preparation of highly active Co-based catalysts is of utmost importance. This paper shows that the conditions during the calcination of impregnated cobalt precursors have a significant influence on the performance of the final catalyst. The options of calcination in rotary kilns, furnaces and fluidized-bed reactors were considered. It was found that the catalyst performance is strongly dependent on the heating rate and the air-space velocity during the preferred option of fluidized bed calcination. The postulation that Co₃O₄ is not the preferred oxide phase of the calcined intermediate catalyst is supported by a temperature-programmed reduction (TPR) study.     

工业催化裂化过程在线工艺计算技术开发与应用

针对MIP工艺的原料（减渣／油浆层、蜡油／回炼油层、柴油层）和产物（汽油、液化气＋干气、焦炭）六个集总组分渣油催化裂化动力学模型,并根据某工业催化裂化提升管反应器流场特性应用序列理想平推流反应器与理想全混流反应器模型的混合反应器模型,建立了工业渣油催化裂化装置反应再生过程工艺计算模型。结合采用由化验值校正和模型参数交替校正的双重校正策略,在某工业连续催化裂化装置上进行在线工艺计算应用,以在线预测过程的裂化产物收率与产物分布。在进料和反应操作条件较大的变化范围内,在线预测趋势和预测精度均令人满意,符合工业过程先进控制的工艺计算精度需求。     

有机硅单体合成流化床反应器研究进展

介绍了应用于有机硅单体合成中的流化床反应器的工作原理及其技术的进展和国内外现状,分析了现有的流化床反应器内部换热结构及底部气体分布器,并指出了的主要优缺点。在此基础上重点介绍了一种新型有机硅单体流化床反应器以及改进的指管束二级管盘式导热油均布器。该设备的特点是：指管束中的导热油并联直流,取热均匀;能耗低,采用了催化剂直接回床技术,代表了有机硅流化床反应器新的发展方向。     

Microstructured reactors and supports for ionic liquids

Different types of microstructures and their applications with respect to the synthesis and the use of ionic liquids are presented. Microstructured reactors are suitable for reactions with fast intrinsic kinetics, requiring high mass and heat transfer performances. Chemical synthesis can be performed safely under operating condition (e.g. high temperature, pressure, etc.) difficult to obtain in traditional reactors. The examples presented clearly indicate that microstructured reactors offer superior performance for the synthesis of ionic liquids in comparison to conventional equipment. For the use of ionic liquids as reaction media, existing ionic liquids show some limitations due to their higher viscosity compared to conventional solvents. Therefore, future research should be focused on the development of low viscosity ionic liquids.The approaches to use ionic liquids in microstructured reactors and in combination with microstructured supports for catalytic reactions show many advantages in view of high product selectivity and yield. The use of supported ionic liquids on microstructured materials seems to be particularly promising for gas phase as well as for gas/liquid reactions.     

Selectivity of aging catalyst in static,moving and fluidized bed reactors

The catalyst decay theory of Wojciechowski is applied to a simplified mechanism of catalytic gas oil cracking. The resulting patterns of selectivity predicted for a static bed reactor are presented in detail and general conclusions are drawn. It is shown that selectivity in gas oil cracking is bounded by optimum and minimum performance envelopes which confine the range of possible product distributions. For the simple cases considered, moving and fluidized bed reactors show selectivity patterns which invariably fall on the optimum performance envelope.     

Producing ethylene and propylene from natural gas via the intermediate synthesis of methyl chloride and its subsequent catalytic pyrolysis

An original two-stage process for producing ethylene and propylene from natural gas via the catalytic pyrolysis of methyl chloride produced by methane catalytic chlorination is investigated. The kinetics of the methyl chloride catalytic pyrolysis on a silicoaluminophosphate catalyst SAPO-34 is studied and the process parameters are determined, yielding selectivities of 45% and 35% for ethylene and propylene, respectively, at 70% conversion of methyl chloride. The kinetics of methane oxidative chlorination is investigated on a catalyst that is a mixture of copper, potassium, and lanthanum chlorides deposited on a carrier. Based on the results from kinetic investigations, the process of methane oxidative chlorination is tested on an experimental setup in reactors of different types, two with fluidized catalyst beds (diameters 400 and 45 mm) and one tubular (diameter 27 mm), and on a pilot setup in a two-stage adiabatic reactor (diameter 800 mm). The process is tested with oxygen supply distributed for each stage at temperatures of 300–320°C at the inlet and 400–420°C at the outlet of the catalyst bed. The selectivity for methyl chloride formation among chloromethanes is 90%. A basic scheme is developed for a chlorine-balanced process of ethylene and propylene production from natural gas, and conditions for conducting methane oxychlorination and methyl chloride pyrolysis reactions in industrial reactors are determined. The process can be implemented at plants that need ethylene to increase deliveries of vinyl chloride and are experienced in working with hydrochloric acid and chlorinated derivatives of hydrocarbons.