催化干气制乙苯装置工业操作方案优化与应用

介绍了干气制乙苯装置两台烃化反应器并联运行的可行性、操作方案及运行数据。大庆炼化公司干气制乙苯装置两个阶段的烃化反应器并联的实践证明：无论是采用调和汽油生产方案,还是乙苯生产方案,烃化反应器的并联,解决了在不开干气压缩机条件下束缚装置提高干气进料量的瓶颈,有效提高了原料干气中的乙烯转化率、以及产品产量,且不影响产品质量;同时,还可以有效降低反应器压降,为催化干气制乙苯装置工业操作方案优化及节能降耗提供参考和借鉴。     

干气制乙苯装置运行及新工艺技术开发

介绍了抚顺石化公司的国内首套催化干气制乙苯气相烷基化(烃化)和液相烷基转移(反烃化)组合的第三代技术工业装置的特点及工业运行情况:通过优化工艺设计,大幅降低了乙苯生产能耗和成本;烃化催化剂和反烃化催化剂呈现出优异的反应活性、抗杂质性能和反应稳定性;由于装置未设干气脱丙烯单元,产品中二甲苯含量略高,达到国家一级品要求;对未来装置技改及更换新一代高性能催化剂提出了建议。所开发的干气与苯变相催化分离制乙苯新一代技术使烃化反应温度进一步降到165~200℃,产品中二甲苯杂质降到100×10-6以下,100 m L规模催化剂(DL0805)放大试验表明,随干气原料中乙烯浓度升高其转化率显著上升,新工艺技术更适于以高乙烯浓度的干气为原料来生产乙苯;反应器中下部适量多乙苯的注入可促进烃化段新生成的多乙苯的完全转化,从而烃化和反烃化过程可集中于一个反应器中进行;DL0805催化剂呈现出较好的反应活性、乙基化选择性及反应稳定性。     

催化裂化干气制乙苯装置反应区管道设计

催化裂化干气制乙苯装置反应区为整个装置的核心区。两台烃化反应器一开一备。主要的工况有:生产工况、活化工况、开工工况。主要工艺介质为催化裂化干气、苯、乙苯。催化剂为器外再生,器内活化。管道设计需要考虑管道柔性、催化剂装卸和有毒介质的排放等问题。     

SEB-08催化剂在干气制乙苯装置的工业应用

中国石油化工股份有限公司广州分公司采用新一代SGEB气相法干气（稀乙烯）制乙苯技术,建成一套年产85 kt干气制乙苯装置。烷基化催化剂使用中国石油化工股份有限公司上海石油化工研究院研制的SEB-08稀乙烯制乙苯催化剂。运行结果表明,SEB-08催化剂可适用不同浓度的稀乙烯原料,具有较强的抗工艺波动能力,原料循环苯中甲苯含量对二甲苯的产生有较大影响,必须严格控制循环苯中甲苯含量;标定结果表明,在反应器入口温度344 ℃、入口压力0.86 MPa、苯与乙烯物质的量比6.71、乙烯质量空速0.297 h^-1和装置反应负荷109%条件下,乙烯转化率为99.73%,乙基选择性为99.65%,二甲苯含量为848×10^-6。SEB-08催化剂具有处理量大、活性高、选择性和稳定性好等优点,有利于提供现有干气制乙苯装置的生产能力。     

稀乙烯制乙苯和纯乙烯制乙苯装置成本和能耗对比

干气制乙苯技术能有效地利用乙烯资源,提高炼油厂效益、降低乙苯产品的生产成本,随着生产技术水平的提高和市场需求的不断增加,干气制乙苯装置逐渐增多,本文对比了广州石化干气制乙苯装置和苯乙烯装置乙苯单元的生产成本和能耗。     

催化干气制乙苯装置工业操作条件优化

催化干气制乙苯气相烷基化和液相烷基转移组合技术及催化剂,可利用干气中乙烯与苯反应生产我国紧缺的乙苯产品,具有良好的适应性。受干气原料限制在相对较低的生产负荷条件运行时,可通过优化脱丙烯系统、提高C3+脱除率、适当提高苯烯比、稳定反应压力、调整干气进料分布、实际生产中充分保护催化剂,减少MDEA、水、液相苯等对催化剂的影响等措施,有效保护催化剂反应性能充分发挥,延长催化剂使用寿命,提高乙苯产量,降低加工成本。     

催化剂装填分率对催化蒸馏干气制乙苯过程的影响

在改性的β沸石催化剂上研究了催化剂与金属填料混合装填条件下,催化剂装填分率对催化蒸馏干气制乙苯过程的影响。通过冷模试验考察了催化剂装填分率对催化剂床层流体力学性能的影响,并在小型的催化蒸馏干气制乙苯装置上考察了催化剂装填分率对反应结果的影响。试验结果表明,催化剂装填体积分率直接影响催化剂床层的流体力学和反应性能。就催化蒸馏干气制乙苯过程而言,适宜的催化剂装填体积分率为10％～30%。     

催化裂化干气烃化制二乙苯

在装有100 mL LaZSM5-Al-Mg催化剂的固定床反应器内进行了质量分数为68.5％的苯和质量分数为18.9％的乙苯混合原料与催化裂化干气制二乙苯反应，在反应温度340 ℃、反应压力0.7 MPa、乙苯空速7 h^-1和n(乙苯)∶n(乙烯)=4.5∶1的反应条件下，乙苯不转化，只消耗苯，乙烯转化率在90%左右，对二乙苯选择性和收率分别为85％和75％左右，无邻位二乙苯生成。同时考察了催化剂的运行寿命。     

催化裂化干气中乙烯制乙苯绝热反应温升和去热方式

本文介绍催化裂化干气中乙烯与苯制乙苯过程反应热平衡,讨论了进料乙烯浓度和苯/乙烯比与反应温升的关系,并论述了烃化反应器分层注入催化干气或苯的取热方式。结果表明,能有效地降低温升,确保催化剂处于最佳温区操作。     

乙苯装置催化干气进料系统改造

乙苯装置烃化反应器催化剂床层反应温升低于设计值,导致乙苯的收率下降,另外,随环境温度的变化参数波动较大;改用SEB-08型烃化催化剂后,要求烃化反应器入口温度提高20℃,现循环苯加热炉热负荷已无法满足生产需要。为此,利用脱氢单元工艺凝液余热将催化干气进行提温,使烃化反应床层温升达到设计要求。改造后,乙苯收率提高0.6%,二乙苯收率下降3.8%,增效约480万元/a;循环苯加热炉的负荷得到下降,减少燃料气费用约250万元/a。     

干气制乙苯反应器自适应在线操作指导的研究(英文)

In this paper, a third-generation dry gas-to-ethylbenzene process in a factory of PetroChina is considered. For the gradual catalyst deactivation in the alkylation reactor, a model is established with the parameters estimated from the reaction rate equation of alkylation based on the on-site data and those from laboratory analysis. The real-time dynamic simulation of the alkylation process is carried out, in which the module accuracy is ensured by using OPC (Object linking and embedding for Process Control) technique and adaptive correction of model parameters. Both the current and future operation temperature can be predicted.     

乙炔前加氢催化剂活性分析方法研究

乙炔加氢催化剂活性对反应器入口CO浓度变化非常敏感,量化CO浓度对催化剂活性的影响程度并预测催化剂活性与反应器入口温度的对应关系十分必要。通过反余切三角函数建立催化剂活性随CO浓度变化的模型,定量描述CO浓度对催化剂活性的影响,并结合反应器入口温度、入口原料气总质量、入口与出口各物质的含量等实际生产数据,优化动力学参数和失活模型参数,定性和定量描述催化剂活性变化后反应器入口温度的调整方法,利用此模型结合相关数据考察反应器入口温度对催化剂活性的影响。     

采用JT-1G 型加氢催化剂优化制氢工艺

长岭炼油化工总厂20000Nm³/h 制氢装置通过采用JT-1G 型加氢催化剂, 反应器入口温度降至200℃, 停开干法脱硫循环机, 加氢后气体的质量指标达到后工序要求。不但降低了成本, 而且简化了工艺, 操作更方便, 并为制氢工艺进一步优化后, 停开制氢干法脱硫反应器奠定了基础。     

EFFECTS OF VARIOUS PROCESS PARAMETERS ON TEMPERATURE PROFILE OF ADIABATIC FIXED BED REACTOR FOR PRODUCTION OF DIMETHYL ETHER (DME) FROM METHANOL

Catalytic dehydration of methanol for production of dimethyl ether (DME) is an exothermic reaction. Therefore, the temperature of the adiabatic reactor of DME production will be increased by the progress of the reaction. In this article, effects of various process parameters are considered on the temperature profile of a fixed catalyst bed in a laboratory-scale reactor of DME production from methanol. Acidic gamma alumina is used for DME production, and effects of inlet feed temperature, flow rate of the feed, pressure of the reactor, and catalyst particle sizes on the temperature profile of the catalyst beds are investigated.     

EFFECTS OF VARIOUS PROCESS PARAMETERS ON TEMPERATURE PROFILE OF ADIABATIC FIXED BED REACTOR FOR PRODUCTION OF DIMETHYL ETHER (DME) FROM METHANOL

Catalytic dehydration of methanol for production of dimethyl ether (DME) is an exothermic reaction. Therefore, the temperature of the adiabatic reactor of DME production will be increased by the progress of the reaction. In this article, effects of various process parameters are considered on the temperature profile of a fixed catalyst bed in a laboratory-scale reactor of DME production from methanol. Acidic gamma alumina is used for DME production, and effects of inlet feed temperature, flow rate of the feed, pressure of the reactor, and catalyst particle sizes on the temperature profile of the catalyst beds are investigated.     

Thermal imaging of catalyst surface during catalytic dehydrogenation of cyclohexane under spray-pulsed conditions

Infra-red thermographic imaging, a tool widely used for screening of active catalytic materials in the field of combinatorial chemistry, has been used during dehydrogenation of cyclohexane on Pt catalyst supported on active carbon cloth and alumite supports. A spray-pulsed reactor with injection of atomized cyclohexane and to create alternate wet and dry conditions on the catalyst surface was used in this study. Since the production rate of hydrogen via endothermic dehydrogenation reaction is greatly dependent on the temperature of the catalyst surface, the temperature profile of the catalyst is important to observe. The observed change in the temperature profile at wet and dry conditions with varying pulse injection frequency and corresponding product gas analysis reveals that the spray-pulse mode is useful in improving the catalyst activity. Further, the comparison between activated carbon support and a more conductive support such as alumite is reported using thermal imaging for more suitable support in this endothermic reaction.     

Dynamic simulation of a cascade fluidized-bed membrane reactor in the presence of long-term catalyst deactivation for methanol synthesis

In this work, a dynamic model for a cascade fluidized-bed hydrogen permselective membrane methanol reactor (CFBMMR) has been developed in the presence of long-term catalyst deactivation. In the first catalyst bed, the synthesis gas is partly converted to methanol in a water-cooled reactor, which is a fluidized-bed. In the second bed, which is a membrane assisted fluidized-bed reactor, the reaction heat is used to preheat the feed gas to the first bed. This reactor configuration solves some observed drawbacks of new conventional dual type methanol reactor (CDMR) and even fluidized-bed membrane dual type methanol reactor (FBMDMR) such as pressure drop, internal mass transfer limitations, radial gradient of concentration and temperature in both reactors. A dynamic two-phase theory in bubbling regime of fluidization is used to model and simulate the proposed reactor. The proposed model has been used to compare the performance of a cascade fluidized-bed membrane methanol reactor with fluidized-bed membrane dual-type methanol reactor and conventional dual-type methanol reactor. The simulation results show a considerable enhancement in the methanol production due to the favorable profile of temperature and activity along the CFBMMR relative to FBMDMR and CDMR systems.     

Dynamic mathematical modeling of a novel dual-type industrial ethylene oxide (EO) reactor

In this paper, the dynamic behavior of a novel dual-type industrial ethylene oxide reactor has been proposed with taking catalyst deactivation into account. The configuration of two catalyst beds instead of one single catalyst bed is developed for conversion of ethylene to ethylene oxide. In the first reactor which is an industrial fixed-bed water-cooled reactor, the feed gas is partly converted to ethylene oxide. This reactor functions at very high yield and at a higher than normal operating temperature. In the second converter, the reaction heat is used to preheat the feed gas to the first reactor and a milder temperature profile is observed. The potential possibilities of a two-stage catalyst bed system are analyzed using a 1D heterogeneous dynamic model to obtain necessary comparative estimates. A differential evolution (DE) algorithm is applied as an effective and robust method to optimize the reactors length ratio. The results obtained from the simulation demonstrate that there is a desirable catalyst temperature profile along the dual-type reactor (DR) compared with the conventional single-type reactor (SR). In this way, the catalysts are exposed to less extreme temperatures and thus, diminishing the catalyst deactivation via sintering. Results from this study provided beneficial information about the effects of reactors configuration on catalyst lifetime and ethylene oxide production rate simultaneously.     

低温液相甲醇合成鼓泡浆态反应器数学模拟

建立了经由甲酸甲酯的低温液相甲醇合成鼓泡浆态反应器的数学模型 ,模拟了实验室鼓泡浆态反应器的行为 ,并利用模型考察了工艺参数如表观气速、催化剂浓度对反应的影响 ,对改进和提高低温液相浆态床反应器甲醇合成提供了信息 ,以便对开发低温甲醇合成工艺提供参考和指导     

Analysis of a two-phase catalytic reaction in a millimeter-scale reactor

The synthesis of a catalyst for a two-phase catalytic reaction, a millimeter-scale reactor experiment, and an analysis model for the prediction of reactor performance are presented in this paper. The catalyst nano-particulate perovskite La_0.8Sr_0.2CoO₃ was prepared by a modified sol-gel method, in which PAA (poly acrylic acid) was added to catalyst precursors. A millimeter-scale reactor experiment with the prepared catalyst was carried. Concentrated hydrogen peroxide was decomposed in the reactor and the characteristics of the reactor were measured in terms of temperature distributions and liquid production rates. The results indicated a flow regime transition, which caused the change of reactor performance. An analysis model for two-phase catalytic reaction based on the lumped flow reactor model and the diagnostic data obtained on the temperature distributions and liquid production rates is proposed. Temperature distributions and heat transfer characteristics of the reactor were predicted by a semi-empirical analysis. In this analysis, the model of the Nusselt number (Nu) was proposed as . This expression of the model reflects the effects of temperature and coordinate location on the heat transfer characteristics of the reactor. From the modeled reactor, characteristics such as the increase of heat transfer in the mid and rear parts of the reactor with the increase of reactant flow rate were obtained. With the obtained results, a tool for the design and analysis of a down-scaled catalytic reaction device was obtained.