减压蜡油加氢裂化六集总动力学模型研究

以实验室加氢裂化催化剂A的加氢裂化反应结果为基础,建立了减压蜡油加氢裂化六集总动力学模型。六集总的划分原则以实际加氢裂化产品切割方案为参照,按馏程把原料油和生成油划分为六个集总,即减压蜡油-加氢裂化尾油(360℃)、柴油馏分(290~360℃)、喷气燃料馏分(175~290℃)、重石脑油(65~175℃)、轻石脑油(65℃)和炼厂气(C4-)。在Matlab 2011b数值计算软件上,利用非线性最小二乘法对动力学模型参数进行了优化回归。通过统计分析,忽略部分集总间的反应,模型预测所得加氢裂化产物收率与实验结果的最大偏差为1.80%,满足工业应用要求。     

减压蜡油加氢裂化催化剂组合动力学模型

以高压加氢裂化六集总动力学模型为基础,建立预测催化剂组合体系产品分布的数学模型。按固定馏程间隔将原料油和加氢裂化生成油划分为减压蜡油 加氢裂化尾油（>360℃）、柴油馏分（290～360℃）、喷气燃料馏分（175～290℃）、重石脑油馏分（65～175℃）、轻石脑油馏分（<65℃）和炼厂气（C4-）6个集总。分别以2种不同类型加氢裂化催化剂的实验数据为基础,采用Matlab 2011b数值计算软件和非线性最小二乘法对动力学模型参数进行了优化回归。以优化回归后的动力学模型参数为初值,调整部分模型参数,建立了预测催化剂组合体系产品分布的数学模型。用该模型计算得到的加氢裂化产品分布与实验值之间的一致性较好,其偏差均小于2%。     

悬浮床加氢裂化产物中酸性含氧化合物的分布

以中东常压渣油为原料,考察其悬浮床加氢裂化产物中酸性含氧化合物的分布情况。在反应温度450℃、反应时间1h、氢初压6MPa的条件下,采用不同催化剂对中东常压渣油进行悬浮床加氢裂化反应,反应产物进行常减压蒸馏,分为IBP～180℃（汽油馏分）、180～360℃（柴油馏分）、360～500℃（蜡油馏分）和>500℃（尾油）,然后测定各馏分和尾油中酸性含氧化合物的含量;采用柱色谱法对蜡油馏分进行三组分分离和对尾油进行四组分分离,并测定各组分中酸性含氧化合物的含量。结果表明,中东常压渣油悬浮床加氢裂化产物中酸性含氧化合物主要分布在蜡油馏分中,其次是分布在尾油中;蜡油馏分中的酸性含氧化合物主要集中在芳香分中,尾油中的酸性含氧化合物主要分布在胶质中。     

悬浮床加氢裂化集总动力学模型的研究

在不同反应温度、氢初压条件下,通过高压反应釜对克拉玛依常压渣油（KLAR）进行加氢裂化实验,以此模拟悬浮床加氢裂化过程,并根据实验数据及实际工艺中对各种轻油产品收率预测的需求建立了悬浮床加氢裂化六集总（气体、汽油、柴油、蜡油、减压渣油、焦）动力学模型,用matlab软件进行编程,采用最小二乘法对动力学参数进行估算,并进行误差分析。结果表明,建立的六集总动力学模型能很好的对各集总产品收率进行预测,计算结果与实验值基本吻合,大部分误差在5%以内。     

中低温煤焦油加氢裂化集总动力学模型的研究

以煤焦油为原料,在高压固定滴流床反应器中,以工业NiMo/Al2O3为催化剂,考察了360-380℃范围内煤焦油的产物分布,基于此建立了5集总煤焦油加氢裂化动力学模型。动力学模型的集总包括：未反应的煤焦油、柴油、汽油、气体和焦炭。通过对实验产物与模型预测产物的对比数据,发现本文所建立的动力学模型可以用于煤焦油加氢裂化过程。同时,基于动力学模型,进一步分析了煤焦油的加氢裂化机理：在整个煤焦油加氢裂化过程中,柴油馏分可作为反应中间组分。     

最大化生产对二甲苯的炼油总工艺流程研究

以规划新建加工15.0 Mt/a沙特轻质和沙特中质混合原油的大型炼油厂为例,按照分子炼油和环状碳链理论,对最大化生产对二甲苯的炼油总工艺流程进行了研究.结果表明,项目的对二甲苯产量可以达到5.0 Mt/a、副产苯1.62 Mt/a.重整原料主要来自:2.28 Mt/a直馏重石脑油(馏程65～ 175℃)、0.96 Mt/a催化裂化重汽油、2.47 Mt/a的柴油(含重芳烃循环)加氢裂化所产的重石脑油和减压蜡油加氢裂化的2.57 Mt/a重石脑油.剩余的芳烃产品来自C4/C5/C6轻烃,芳构化可产1.52 Mt/a富含芳烃的生成油,催化干气稀乙烯可直接生产0.12 Mt/a乙苯.     

加氢裂化工艺操作过程的优化分析

通过样条曲线插值的数学方法,建立了加氢裂化反应过程中的处理量、温度对裂化产品物化性质影响的数值模型,并将该模型应用于减压蜡油（VGO）的加氢裂化工艺优化分析。该优化问题以VGO加氢裂化反应的处理量和温度为变量,以产品中喷气燃料馏分的烟点、冰点,柴油馏分收率以及中油选择性作为约束条件,考察在上述约束条件下工艺操作参数的可行区间,并在此相关条件约束下,基于所确立的数学模型计算相关转化率的最小值,以便获得系统高产尾油时的工艺操作参数,并与实验数据进行对比。对比结果表明,该方法效果良好,所得数据与实验数据相近。     

中压加氢裂化生产合格喷气燃料技术开发与应用

为满足市场对喷气燃料的需求并与企业现有装置相契合，中国石化石油化工科学研究院（简称石科院）开发了生产合格喷气燃料的中压加氢裂化技术。通过考察反应压力、裂化催化剂、原料油、转化深度及体积空速对喷气燃料性质的影响规律，提出了中压条件生产合格喷气燃料的加氢裂化技术方案。中压加氢裂化生产合格喷气燃料技术在中国石化上海石油化工股份有限公司1.5 Mt/a中压加氢裂化装置得到工业应用，在国内首次实现了中压条件下蜡油生产合格喷气燃料。装置工业标定结果表明，采用该技术加工高硫减压蜡油（VGO）馏分，在氢分压约10 MPa的条件下，喷气燃料馏分收率达到20%以上，且满足3号喷气燃料质量要求，尾油馏分BMCI值约为10，是优质的裂解制乙烯原料。     

哈国原油VGO加氢裂化性能研究

以哈萨克斯坦原油生产的减压蜡油(VGO)为原料油,在相同的反应压力16 MPa、氢油比900,反应温度385~393℃、空速0.6~0.9 h-1的条件下,通过试验考察VGO加氢裂化后转化率变化情况:转化率随反应温度的提高而增加,随空速的增大而降低。同时通过对加氢裂化产品蒸馏数据及产品主要性质分析看出:加氢裂化轻石脑油是较好的乙烯裂解原料,重石脑油是较好的重整原料,轻柴油可作为-20号柴油至-50号车用柴油的主要调合组分,重柴油可作为各种规格柴油调合组分,尾油可作为乙烯裂解原料。     

焦化蜡油溶剂精制油的加氢裂化工艺研究

为合理利用焦化蜡油、洛阳石化工程公司炼制研究所开发了焦化蜡油溶剂精制－加氢裂化组合工艺,中型试验结果表明,焦化蜡油经溶剂精制可以脱除80％的氮和40％的硫,得到的精制油质量接近相应的直馏蜡油,可以直接作为加氢裂化原料,抽出的重芳烃可作为化工原料,抽出的轻芳烃的某一段窄馏分再掺入加氢裂化原料可以提高加氢裂化重石脑油的芳烃潜含量。     

A Four Lump Kinetic Model for the Simulation of the Hydrocracking Process

Hydrocracking is a very important secondary refining process used to convert low value vacuum gas oils into high value fuels. The chemistry of the hydrocracking process is very complex due to the involvement of high molecular weight complex hydrocarbons in the reactions. Process modeling and simulation of the hydrocracking unit is very challenging due to the complexities of chemistry and the process. In the present work, a mathematical model is described to analyze the performance of the hydrocracking process in terms of product yields. A four lump discrete lumping approach is employed with a hydrocracking reaction scheme involving six reactions. The kinetic constants for the reactions were estimated by minimizing the error between the experimental and predicted yields of kinetic lumps. Experimental data reported by Ali et al. (2002) were used to validate the proposed model. The model predictions were found to agree well with the experimental data. The proposed model can be used to simulate the performance of commercial hydrocrackers using kinetic parameters estimated from pilot plant experiments.     

Hydrocracking of Vacuum Gas Oil: Conversion,Product Yields,and Product Quality over an Industrial Hydrocracking Catalyst System

Pilot plant experiments were conducted over an industrial hydrotreating/hydrocracking catalyst system using vacuum gas oil fraction obtained from a refinery crude distillation unit. Extensive pilot plant data were generated on the performance of industrial hydrocracking catalyst system with respect to conversion, product yields, and product quality at various operating conditions. The pilot plant experiments were carried out in a dual-reactor hydrotreating pilot plant system with downflow mode of operation. The temperature varied from 360 to 400°C and liquid hourly space velocity varied from 0.8 to 2.4 hr^?1, keeping a constant pressure of 170 kg/cm² and H₂/HC feed ratio of 845 L/L. The hydrocracked total liquid product was distilled in a true boiling point distillation unit to obtain yields and qualities of different fractions such as naphtha, kerosene, diesel, and unconverted oil. The effect of operating conditions on the performance of the hydrocracking catalyst system was discussed in detail. The kinetics of hydrocracking reaction was studied using a simple first-order reaction and a complex four-lump reaction system and the kinetic parameters were reported.     

加氢裂化装置产品结构优化方案及效果

针对国内成品油市场柴油需求减少而喷气燃料、重石脑油和加氢裂化尾油等产品需求增加的实际情况,炼化企业利用加氢裂化装置可以灵活调整产品方案的特点,通过采用部分更换新型加氢裂化催化剂、不同性能加氢裂化催化剂级配、调整和优化产品切割方案以及以柴油为原料生产白油等技术措施,可以提高加氢裂化装置的喷气燃料、重石脑油以及加氢裂化尾油产品的收率,降低柴油收率,改善加氢裂化喷气燃料、尾油产品的质量,充分发挥加氢裂化装置在产品结构灵活调整方面的优势。加氢裂化装置调整产品结构方案在Y公司和M公司2个企业的应用结果表明,加氢裂化装置喷气燃料收率增加3.58～13.28百分点,柴油收率减少5.14～5.81百分点,喷气燃料冰点降低1 ℃以上,尾油BMCI降低1.2～1.7。     

MILD HYDROCRACKING OF VACUUM GAS OILS TO IMPROVE FCC PERFORMANCE AND MAXIMIZE DISTILLATE YIELDS

A pilot plant study was conducted on mild hydrocracking of heavy vacuum gas oils derived from two different crude sources over a commercially available catalyst to determine the possibility of utilizing mild hydrocracker bottoms as fluidized catalytic cracking feedstock along with improved middle distillate yields. The mild hydrocracking experiments were conducted at 390°C, 60 kg/cm², 1.0/h liquid hourly space velocity and H₂/oil ratio of 390 l/l in a pilot plant trickle bed reactor using two catalyst beds for pretreatment and mild hydrocracking reactions. The experimental results showed that mild hydrocracking would result in valuable middle distillates with low sulphur and nitrogen content. With research octane number of 78, the naphtha obtained from mild hydrocracking was found to be a good blending stock for gasoline pool. The middle distillate fraction (140-370°C) obtained from mild hydrocracking product was found to have cetane number in the range of 48-54. The bottom product from mild hydrocracking of heavy vacuum gas oils was found to be a good feedstock for fluidized catalytic cracking unit because of its low sulphur, nitrogen and aromatic contents. The data obtained from pilot plant studies showed that the processing of mild cracker bottom in FCC unit would result in better quality fuels.     

MILD HYDROCRACKING OF VACUUM GAS OILS TO IMPROVE FCC PERFORMANCE AND MAXIMIZE DISTILLATE YIELDS

ABSTRACT

A pilot plant study was conducted on mild hydrocracking of heavy vacuum gas oils derived from two different crude sources over a commercially available catalyst to determine the possibility of utilizing mild hydrocracker bottoms as fluidized catalytic cracking feedstock along with improved middle distillate yields. The mild hydrocracking experiments were conducted at 390°C, 60 kg/cm², 1.0/h liquid hourly space velocity and H₂/oil ratio of 390 l/l in a pilot plant trickle bed reactor using two catalyst beds for pretreatment and mild hydrocracking reactions. The experimental results showed that mild hydrocracking would result in valuable middle distillates with low sulphur and nitrogen content. With research octane number of 78, the naphtha obtained from mild hydrocracking was found to be a good blending stock for gasoline pool. The middle distillate fraction (140–370°C) obtained from mild hydrocracking product was found to have cetane number in the range of 48–54. The bottom product from mild hydrocracking of heavy vacuum gas oils was found to be a good feedstock for fluidized catalytic cracking unit because of its low sulphur, nitrogen and aromatic contents. The data obtained from pilot plant studies showed that the processing of mild cracker bottom in FCC unit would result in better quality fuels.     

Kinetic Study on the Hydrocracking Reaction of Vacuum Residue Using a Lumping Model

Abstract

Based on the experimental hydrocracking of vacuum residue, a kinetic study using a lumping model was carried out to gain insight into the characteristics of catalytic reactions. The lumped species were the saturates, aromatics, resins, and asphaltenes (SARA) constituents in the residue (798 K⁺) fraction and gas, naphtha, kerosene, gas oil, vacuum gas oil, and coke in the products. The pyrite reaction favoring hydrocracking to lighter products was more temperature-dependent than that using a mixture of pyrite and active carbon. The kinetic study showed that the addition of active carbon to pyrite limited the transformation of resins to asphaltenes.     

Kinetic Study on the Hydrocracking Reaction of Vacuum Residue Using a Lumping Model

Based on the experimental hydrocracking of vacuum residue, a kinetic study using a lumping model was carried out to gain insight into the characteristics of catalytic reactions. The lumped species were the saturates, aromatics, resins, and asphaltenes (SARA) constituents in the residue (798 K⁺) fraction and gas, naphtha, kerosene, gas oil, vacuum gas oil, and coke in the products. The pyrite reaction favoring hydrocracking to lighter products was more temperature-dependent than that using a mixture of pyrite and active carbon. The kinetic study showed that the addition of active carbon to pyrite limited the transformation of resins to asphaltenes.     

加氢裂化柴油催化蒸馏制取特种油品的研究

采用催化蒸馏技术对加氢裂化柴油馏分进行脱蜡和产物分离以制取特种油品。考察了催化蒸馏塔结构参数和工艺条件的影响,结果表明,在反应温度300－315℃、反应空速1．25h^-1、一线（汽油）回流比0．9－1．1、四线（轧制油）回流比0．4－0．6、塔底温度330－335℃的条件下,处理加氢裂化柴油馏分并经白土补充精制,可以制得78．0％的N5油（5号机械油）或52．0％的DB10油（10号变压器油）,产品质量符合国家标准,并副产汽油、煤油、轧铝板用轧制油、干气和液化气,催化剂反应性能和稳定性能良好。