轻柴油蒸汽热裂解结焦动力学

将热重天平改装成可连续测量石油烃水蒸汽热裂解结焦速度的流动积分反应装置。研究了柴油结焦速度与温度、烃分压和动力学裂解深度的关系及小试与工业炉的结焦过程,建立了结焦动力学方程。结果表明,同小试一样,工业炉的结焦反应也为反应动力学控制。结焦速度和结焦母体随裂解深度的变化表明,原料中带支链的芳烃和二次反应中生成的“聚合物”是活性很高的结焦母体。     

石油馏份蒸汽裂解结焦机理探讨

轻柴油高深度裂解时，结焦母体的浓度和分子量相当大，因此，结焦速度与反应时间无关。当利用裂解深度相等时的结焦速度常数求取活化能时，小试的活化能与工业炉的相近。基于结焦反应控制论建立了工业炉结焦方程。     

轻质油裂解炉管结焦模型的研究

轻质油裂解时,在气相中由低分子不饱和烃与芳烃缩合生成"结焦母体",然后母体扩散到反应管内壁,进行表面反应变成焦.母体的物化性质及模型中大部分参数由结焦试验数据拟合确定.母体的传质系数根据扩散传质原理计算,用所得模型,对大庆乙烯联合化工厂三种不同轻烃、轻质油裂解炉,进行了沿反应管长、且随运转天数而变的结焦厚度及其它工况的计算,得到了满意的结果.     

轻柴油裂解结焦反应模型研究

本文研究了轻柴油馏分水蒸气裂解结焦反应动力学,实验条件为:温度1063～1208(K)、停留时间0.02～1.2(s)、稀释比(水/油)0.2(m/m)。考察了轻柴油的裂解及结焦的性能,建立了轻柴油水蒸气裂解的数学模型和结焦过程的数学模型,确定出结焦前兆体为乙烯和芳烃。实验表明轻柴油裂解结焦过程属反应动力学控制过程。本文建立的数学模型可用于工业炉轻柴油裂解的产物分布预测及焦炭分布的预测。     

芳烃抽提法优化乙烯联合装置的裂解原料

根据裂解和结焦反应理论,分析了石脑油裂解反应中芳烃结焦过程的规律,研究了石脑油族组成与乙烯收率的关系,选择了用于计算乙烯联合工艺装置综合能耗的统一基准。在石脑油中烷烃和环烷烃含量相同或相近的条件下,降低石脑油的芳烃含量可提高乙烯收率并减少结焦。在不增加工艺装置和设备的前提下,提出了优化裂解原料的前抽提乙烯联合装置工艺流程(简称前抽提流程),即先将石脑油送芳烃抽提装置分离出芳烃,再将抽余石脑油送裂解炉生产乙烯。选择低能耗芳烃抽提技术,可使前抽提流程总能耗低于常规乙烯联合装置工艺流程的总能耗。     

由重质馏分油生产烯烃的新途径

烃类裂解过程中结焦主要是由原料中芳烃化合物以及裂解气二次反应形成的。随着原料馏分沸点的升高,芳烃含量亦增加,可采用芳烃抽提、催化加氢以及加氢裂化等工艺使芳烃转化。     

裂解汽油加氢试验

裂解汽油是轻油高温裂解制乙烯的付产品,芳烃含量高,是世界上生产芳烃的主要原料。但裂解汽油中含有较多的烯烃、二烯烃等,必须进行深度加氢精制,才能取得合格的芳烃产品。现将我所裂解汽油加氢小型     

重油催化裂解过程中丙烯和干气的生成历程

采用固定床微反实验装置考察了大庆蜡油不同转化深度下的催化裂解反应的产物分布,探讨了重油催化裂解过程中丙烯和干气的生成历程。结果表明,重油催化裂解过程中,丙烯的生成是原料一次裂解和汽油馏分二次裂解共同作用的结果。当原料转化深度较低时,丙烯已由原料中烷烃的一次裂解反应大量生成;随着原料转化深度的增加,汽油馏分二次裂解生成丙烯的反应所占比重增大。在原料一次裂解为主生成丙烯的反应阶段内,干气主要由烷烃发生单分子裂化反应生成,而在汽油馏分二次裂解为主生成丙烯反应阶段内,芳烃和烯烃缩合生焦反应对干气生成的影响更为显著。     

石脑油蒸汽热裂解过程中的结焦速率研究

在实验室蒸汽热裂解装置(BSPA)上,考察了石脑油进料质量流速、裂解温度、烃分压和运行时间等反应条件对石脑油热裂解过程中裂解炉管结焦速率的影响。结果表明,在石脑油进料速率为90 g/h,水油质量比为0.6,炉管进口压力为0.05 MPa的条件下运行6 h,随着裂解温度的升高,裂解炉管结焦速率逐渐增大;当裂解温度为850℃时,结焦速率与烃分压呈线性关系;随着裂解炉运行时间的延长,结焦速率下降。     

“乙烯工业裂解炉模拟优化系统2.0版本”成功申请国家软件著作权

中国国家版权局公报显示,由石油化工研究院、兰州石化公司和清华大学历时3年开发的"乙烯工业裂解炉模拟与优化软件系统(简称EPSOS)V2.0",成功申请国家版权局著作权证书,可在乙烯装置推广应用。EPSOS2.0系统研发经历了实验室裂解性能评价、工业炉标定、裂解过程动力学研究、结焦动力学研究,建立了不同裂解原料的分子反应动力学模型和结焦动力学模型,并通过大量的工业炉运行数据,对模型参数进行修正,最终形成了乙烯裂解炉模拟与优化系统。该系统能够     

延迟焦化石油焦热重分析及热解动力学

对延迟焦在CO2和Ar两种气氛下,从室温至1 000 ℃进行热重分析,探讨其热解机理。研究表明, 延迟焦热解过程首先经历50~100 ℃的脱水阶段,较明显的失重从400 ℃开始,在620~640 ℃失重速率达到峰值,800 ℃之后快速失重,热失重速率不断增加。以三级化学反应模型模拟热解过程,在433~904 ℃的热解温度范围内,CO2气氛下的平均活化能为29.70~44.81 kJ/mol,Ar气氛下的平均活化能为57.68~69.44 kJ/mol。     

Modeling of Coke Formation and Catalyst Deactivation in Propane Dehydrogenation Over a Commercial Pt-Sn/γ-Al2O3 Catalyst

Propane dehydrogenation was carried over a commercial Pt-Sn/γ-Al₂O₃ catalyst at atmospheric pressure and reaction temperatures of 580, 600, and 620°C and WHSV of 11 h^?1 in an experimental tubular quartz reactor. Propane conversions were measured for catalyst time on stream of up to nine days. The amounts of coke deposited on the catalyst were measured after one, three, six, and nine days on stream using a thermogravimetric differential thermal analyzer (TG-DTA) for each reaction temperature. The coke formation kinetics was successfully described by a coke formation model based on a monolayer-multilayer mechanism. In addition, catalyst deactivation was presented by a time-dependant deactivation function. The kinetic order for monolayer coke formation was found to be two, which would support a coke formation step involving two active sites. The kinetic order for multilayer coke formation was found to be zero. The activation energy for monolayer coke formation was found to be 29.1 kJ/mol, which was lower than the activation energy of about 265.1 kJ/mol for multilayer coke formation indicating that the presence of metals can promote coke formation on the catalyst surface.     

Thermal Hydrocracking Kinetics of Chinese Gudao Vacuum Residue

The thermal hydrocracking kinetics of Chinese Gudao vacuum residue was studied in a batch autoclave reactor. The temperature ranged in 390-435°C and the initial hydrogen pressure was 7.0 MPa at 20°C. Ammonium phosphomolybdate (APM) in its dispersed phase was the catalyst. The reaction products, gas, naphtha, atmospheric gas oil (AGO), vacuum gas oil (VGO) and coke, were separated during and after experiments, and their yields vs. reaction time were obtained, for four reaction temperatures: 390, 405, 420, and 435°C. The activation energy was calculated from a traditional kinetic model to be 218.6 kJ/mol. A new kinetic model was proposed in this work that allows for the calculation of activation energy with a minimum number of three tests, each at a different temperature. This is comparable to the traditional model which requires a minimum of 12 tests; a minimum of four tests for one temperature and a minimum of three temperatures. The activation energy calculated from the new model with four tests is 229.6 kJ/mol, only 5% greater than that obtained from the traditional model. The reaction rate constants obtained from this model are also consistent with those from the traditional model.     

Thermal Hydrocracking Kinetics of Chinese Gudao Vacuum Residue

Abstract

The thermal hydrocracking kinetics of Chinese Gudao vacuum residue was studied in a batch autoclave reactor. The temperature ranged in 390–435°C and the initial hydrogen pressure was 7.0 MPa at 20°C. Ammonium phosphomolybdate (APM) in its dispersed phase was the catalyst. The reaction products, gas, naphtha, atmospheric gas oil (AGO), vacuum gas oil (VGO) and coke, were separated during and after experiments, and their yields vs. reaction time were obtained, for four reaction temperatures: 390, 405, 420, and 435°C. The activation energy was calculated from a traditional kinetic model to be 218.6 kJ/mol. A new kinetic model was proposed in this work that allows for the calculation of activation energy with a minimum number of three tests, each at a different temperature. This is comparable to the traditional model which requires a minimum of 12 tests; a minimum of four tests for one temperature and a minimum of three temperatures. The activation energy calculated from the new model with four tests is 229.6 kJ/mol, only 5% greater than that obtained from the traditional model. The reaction rate constants obtained from this model are also consistent with those from the traditional model.     

辽河石脑油裂解装置急冷锅炉结焦抑制剂的研究

用实验装置,在辽河石脑油裂解的急冷锅炉温度条件下,对含硫、磷的金属有机化合物(CRS)、二甲基硫(DMS)、高含硫无机化合物(Ry)进行了抑制结焦性能的研究。用测焦挂片,烧焦和分析裂解气中CO、CO_2含量相结合的方法,测定结焦速率。在石脑油中加入200×10~(-6)kg/kgCRS或DMS,或加300×10~(-6)kg/kg Ry,均能使高温反应结焦速率降低30％左右。在急冷锅炉后部低温条件下,金属表面先涂以CRS石脑油溶液,能降低冷凝结焦速率。     

Coking behavior and kinetics study of a catalytic in-situ combustion process for heavy oil

Coke formation is one of the key factors that determine the success and the economy of an ISC project. The isoconversional method is employed to study kinetics of heavy oil low temperature oxidation and pyrolysis where coke is formed based on a set of experimental data. The activation energies of low temperature oxidation and pyrolysis are lowered by 9.741?kJ/mol and 17.030?kJ/mol upon adding α · Fe₂O₃ catalyst, respectively. More coke is produced with increasing temperature, extended reaction time and the increasing fraction of O₂. The coke amount can be reduced by adding α · Fe₂O₃ catalyst.     

馏份油热裂解炉汽化段结焦机理探讨

裂解炉对流段结焦和结焦母体生成速率的研究表明，雷诺数和线速度的乘积愈大和反应深度愈低，结焦速度愈小。重油汽化呈环流时管壁不结焦，仅当准雾状流时才结焦。雷诺数和线速度的乘积越大，临界汽化率越大。     

新型结焦抑制剂PCI-Ⅱ抑焦性能及其模型

以盘锦乙烯工业公司提供的石脑油为原料 ,在实验室小型连续管式裂解炉上 ,对石脑油在不同温度下的结焦规律进行了测试。分别考察了二甲基二硫 (DMDS)和磷酸二异丁脂的环己胺盐 (PCI -Ⅱ )存在下石脑油裂解结焦抑制剂的性能 ,同时考察了裂解温度对结焦速率的影响。结果表明 ,PCI -Ⅱ作为一种新型结焦抑制剂其功能完善 ,抑焦效果优于DMDS ;同时PCI-Ⅱ的加入可提高乙烯收率。根据实验数据对PCI -Ⅱ的抑焦性能进行了模型化