A lumped kinetic model for heavy oil catalytic cracking FDFCC process

Based on the reaction mechanisms and the characteristics of flexible dual-riser fluid catalytic cracking (FDFCC) process, the reaction networks of 10 lumps for heavy oil and seven lumps for gasoline were put forward. The cracking reactions of resin and asphaltene into gasoline and gases in heavy oil riser reactor were considered as second-order ones while the other reactions were described as first-order ones. The kinetic parameters indicate good consistence with the reaction rules of heavy oil catalytic cracking. The relative errors between calculated values and actual values of products are all less than 4%, which shows the reliability of the models.     

FCC反应机理与分子水平动力学模型研究 III.重油催化裂化模型的建立

将一种基于催化裂化反应机理的动力学模型应用于重油催化裂化过程,实验确立了几种典型的催化裂化催化剂的反应速率常数。模拟实验的结果表明,通过实验确定的各反应速率常数不仅可以对重油催化裂化产品的产率分布进行模拟和预测,而且可以较为准确地对产品族组成进行模拟和预测。该模型包含十四个集总共24个反应速率常数,易于在提升管反应器上应用。     

FCC反应机理与分子水平动力学模型研究Ⅲ.重油催化裂化模型的建立

将一种基于催化裂化反应机理的动力学模型应用于重油催化裂化过程，实验确立了几种典型的催化裂化催化剂的反应速率常数。模拟实验的结果表明，通过实验确定的各反应速率常数不仅可以对重油催化裂化产品的产率分布进行模拟和预测，而且可以较为准确地对产品族组成进行模拟和预测。该模型包含十四个集总共24个反应速率常数，易于在提升管反应器上应用。     

A Kinetic Model for Flexible Dual-riser Fluid Catalytic Cracking Process

According to the mechanism of catalytic cracking reactions, the characteristics of flexible dual-riser fluid catalytic cracking (FDFCC) process, a 10-lumped kinetic model for heavy oil riser reactor and a seven-lumped kinetic model for gasoline riser reactor were developed in the article to simulate the FDFCC process. Based on the data from a commercial FDFCC unit, 43 kinetic parameters for the ten-lumped kinetic model and 18 kinetic parameters for the seven-lumped kinetic model were calculated by the stepwise method. The validity check of the model show that the calculated values of the models are close to the commercial data. In general, the two models could not only describe reaction rules of the FDFCC process correctly but also give good prediction for the distribution and composition of main products, especially for gasoline and propylene.     

结构导向集总方法构建直馏汽油催化裂化动力学模型

采用结构导向集总(SOL)新方法构建了直馏汽油催化裂化改质的反应动力学模型。模型选取74种分子组成原料矩阵,根据催化裂化正碳离子反应机理,制定了42种反应规则构建反应网络。采用矩阵变换的形式求解反应网络,从而得到产物分子矩阵。通过对产物矩阵中的分子归类,获得产物分布及汽油族组成。采集实验室小型固定流化床催化裂化数据,对模型计算结果进行验证。结果表明,该模型能较为准确地预测产物分布及汽油族组成;在温度及进料组成改变时,模型适应性较好;模型同样能较准确地预测汽油研究法辛烷值。     

A new lumping kinetic model for fluid catalytic cracking

Abstract

In the modeling of fluid catalytic cracking reaction, it is necessary to take slurry as an independent lump due to the great difference between feedstock properties and slurry properties. Based on the commercial data and the reaction mechanism of catalytic cracking, the 8 lumped kinetic model including slurry lump and 7 lumped kinetic model excluding slurry lump were developed combined with the characteristics of the MIP (maximizing isoparaffins) reaction. By means of Fourth-order Runge-Kutta integral method and two-swarm cooperative particle swarms optimization method, the kinetic model parameters were estimated, respectively. The average relative error between commercial data and calculated values, as well as the results of product predictions, indicate that the eight-lumped kinetic model has higher prediction accuracy, and the predicted results of slurry yield are more in line with the actual industrial conditions.     

催化裂化复杂反应体系动力学模型研究进展

系统介绍催化裂化复杂反应体系反应动力学模型研究进展,其中包括关联模型、集总模型和分子模型。对这些模型的建立原则、计算方法、工业应用等方面进行了深入分析,总结了各类模型建立的一般原则和规律,并对其未来的发展方向作了预测。     

Lump kinetic study of waxy distillate catalytic cracking in microactivity tests

The catalytic cracking of waxy distillate was investigated using equilibrium residue fluid catalytic cracking catalyst in a microactivity setup. The effect of temperature on gasoline yield was studied and a four-lump kinetic model including six reaction rates was employed. The kinetic parameters were calculated based on the experimental data using the fourth-order Runge–Kutta method and Marquardt's algorithm least square error. Activation energies and frequency factors were calculated using the Arrhenius equation. The highest gasoline yield was observed in the temperatures between 520 and 540°C, while the undesired gas products increased in higher temperatures.     

FDFCC工艺降低催化裂化汽油烯烃含量

FDFCC工艺是降低催化汽油烯烃含量的有效技术。论述了该工艺的技术特点、流程设计和工业应用情况。工业应用结果表明,该工艺可使烯烃体积分数降低30个百分点左右,硫含量下降20％左右,改质汽油诱导期增加,MON和RON略有增加,并且苯含量基本维持不变,芳烃含量远远小于规定指标40％。     

Study on Lumped Kinetic Model for FDFCC II. Validation and Prediction of Model

On the basis of formulating the 9-lump kinetic model for gasoline catalytic upgrading and the 12-lump kinetic model for heavy oil FCC, this paper is aimed at development of a combined kinetic model for a typical FDFCC process after analyzing the coupled relationship and combination of these two models. The model is also verified by using commercial data, the results of which showed that the model can better predict the product yields and their quality, with the relative errors between the main products of the unit and commercial data being less than five percent. Furthermore, the combined model is used to predict and optimize the operating conditions for gasoline riser and heavy oil riser in FDFCC. So this paper can offer some guidance for the processing of FDFCC and is instructive to model research and development of such multi-reactor process and combined process.     

Study on Lumped Kinetic Model for FDFCC I. Establishment of Model

According to the process features and the reaction mechanism of FDFCC technology, its two reaction subsystems, one for heavy oil riser reactor, the other for gasoline riser reactor, were respectively studied. Correspondingly, a 12-lump kinetic model for heavy oil FCC and a 9-lump kinetic model for gasoline catalytic upgrading were presented. Based on this work, mathematical correlation of the lumps in the feeds and products involved in the reaction subsystems and those of the overall reaction system were analyzed in detail. Then, a combined kinetic model for FDFCC, which was based on the data recovered from a commercial unit, was put forward. The reaction performance embodied by the kinetic constants for the combined model of FDFCC was in accordance with catalytic cracking reaction mechanism. The model-calculated values were close to the data obtained in commercial scale. The model was easy to be applied in practice and could also provide some theoretical groundwork for further research on kinetic model for FDFCC.     

降低催化汽油烯烃含量的催化裂化工艺分析

汽油新标准的实施和与国际接轨的趋势要求降低我国成品汽油中的烯烃含量,笔者从催化裂 化反应工艺角度对已经实现工业化和正在开发的降烯烃技术进行了分析和探讨。     

The Establishment of a Lumped Kinetic Model for FDFCC

Abstract

The purpose of this study is to develop a lumped kinetic model for a typical flexible dual-riser fluid catalytic cracking (FDFCC) process, which is dissected into two reaction subsystems, and two related models are put forward, respectively. Afterward, the mathematical association is detailed and analyzed for the models. Then, one combined kinetic model for the overall process is presented. Finally, the combined model is verified with two sets of various industrial data under different operating conditions, and the results show that the model-predicted values were closely associated with the industrial data. The presented model could be instructive to optimize the operating conditions for the commercial process.     

重油催化裂化装置节能优化分析

结合中国石化中原油田分公司石油化工总厂的重油催化裂化装置的实际生产情况,对装置进行了能耗分析,指出装置的节能降耗方向。通过实施节能风机改造、提高空冷利用效率、主风节能系统改造、应用新型保温材料及优化烟机检修方法等措施,使催化裂化装置的能耗降低,节能效果明显,经济效益显著。2015年装置的能耗(以标油计)比2012年下降了15.19 kg/t,其中,电能降低4.28 kg/t,由于蒸汽消耗量下降,蒸汽外输增加了3.80 kg/t。该装置的节能优化对国内其他炼油企业的节能工作具有一定的借鉴意义。     

加氢裂化尾油裂解工艺及结构导向集总模型

以上海高桥石化加氢裂化尾油为原料,在蒸汽裂解制乙烯实验装置上考察了裂解温度、停留时间和水/原料油(简称水油比,质量比,下同)对裂解产物收率的影响;同时,采用结构导向集总方法建立了加氢裂化尾油蒸汽裂解制乙烯的反应动力学模型。结果表明,优化的蒸汽裂解制乙烯操作条件为:裂解温度800℃,停留时间0.53 s,水油比0.75。在此条件下,裂解气收率为84.47%,乙烯、丙烯和丁二烯的收率依次为31.35%,19.93%,4.07%。模型计算值与实测值具有较好的一致性。     

Prediction of the product yield from catalytic cracking (MIP) process by an 8-lump kinetic model combined with neural network

Based on the characteristics of maximizing iso-paraffins (MIP) process and industrial data, an 8-lump kinetic model for MIP process is developed. And the 47 kinetic parameters of the model are calculated by Runge-Kutta method and genetic algorithm. It is seen that kinetic parameters show good consistence with the reaction mechanism of catalytic cracking. The average relative errors between calculated values and real values of product distribution are all below 5%. Then the model is modified by 14-7-5 type of back propagation (BP) neural network. As a result, the product distribution can be predicted more accurately by the hybrid model. Therefore, the combination of lump model and neural network can provide a new direction for simulation and optimization for heavy oil catalytic cracking.     

重油催化裂化装置MGD技术工业应用

中国石化九江分公司Ⅱ套催化裂化装置应用MGD技术使催化汽油烯烃含量降低了约8个单位,同时增产了液化气和柴油,效果显著,达到了预期目的。     

碱土金属催化剂催化裂解重油实验研究

采用小型流化床实验装置,以减压渣油为原料,铝酸镁为催化剂,考察反应温度、水油比、催化剂装填量等条件对重油催化裂解反应气体产物分布的影响;同时,还考察了不同催化剂对重油催化裂解三相组成和气体产物分布的影响。研究结果表明,各操作条件对重油催化热解实验产物存在不同程度的影响,其中温度影响最大,在反应温度为750℃、水油比为2、催化剂装填量为40g等最优条件下,乙烯质量产率为11.89%,总烯烃质量产率为20.19%。通过对不同催化剂的比较,铝酸镁的选择性优于铝酸钙,铝酸钙的产率优于铝酸镁。     

催化裂化重汽油加氢脱硫工艺研究

以馏程大于70℃的催化裂化重汽油为原料,在装填OTC—M型催化剂的30mL微型固定床反应评价装置上,进行加氢脱硫的工艺研究。结果表明,优化的加氢条件为：反应温度260℃、反应压力1．6MPa、氢油体积比300：1、进料空速4h^-1;在此工艺条件下,重汽油的硫含量由272．35μg／g降至124．78μg／g,脱硫率达54．18％。