催化裂化汽油烯烃选择性裂解制丙烯工艺的开发

针对催化裂化汽油中烯烃含量高,国际市场对丙烯需求量大的现状,在扬州石化有限责任公司工业侧线装置上进行了FCC汽油烯烃裂化制丙烯工艺的工业试验。该工艺采用分子筛涂覆的规整结构催化剂,在自建的20 kg/h工业小试装置上,按照优化的工艺参数和工艺过程,促进FCC汽油中烯烃的选择性裂化,在降低汽油烯烃含量的同时,气相产物中三烯(乙烯、丙烯和丁烯)的选择性可大于80%,其中丙烯选择性可达到30%～40%。     

FCC汽油烃重组生产高辛烷值汽油并联产乙烯裂解料

采用烃重组技术处理催化裂化(FCC)汽油(已经过加氢脱硫处理),既可获得质量满足国Ⅲ、国Ⅳ标准且研究法辛烷值比加氢前提高2个单位的汽油,同时联产可作为优质乙烯裂解原料使用的烷烃.蒸汽裂解评价结果表明,以烃重组C≥6石脑油为原料,三烯收率大于48％,m(丙烯)/m(乙烯)约为0.5.烃重组技术不仅可显著提高炼化一体化程度,还可为炼油厂优化FCC、重整等生产装置,增产高附加值产品增加机会,经济效益显著.     

催化裂化汽油烯烃转化增产丙烯工艺研究

在装有条形ZRP催化剂的固定床反应器上,考察了催化裂化汽油在ZRP稀土改性催化剂上的反应性能,反应温度、空速、原料中水油比等工艺条件对催化裂化汽油烯烃转化率和低碳烯烃收率、选择性的影响。实验结果表明：ZRP稀土改性催化剂可选择性地将催化裂化汽油中C5～C8烯烃催化裂解,提高催化裂化汽油烯烃的转化率和丙烯的收率;反应的适宜温度为550-580℃;在保证烯烃转化率的条件下,适当提高反应空速可以获得较高的丙烯、乙烯收率;引入适量的水蒸气可以起到稀释作用,能够使反应平衡向丙烯方向移动。     

Separating group compositions in naphtha by adsorption and solvent extraction to improve olefin yields of steam cracking process

In order to improve the steam cracking feeds, several model compounds including normal paraffins, iso-paraffins, cyclanes and aromatics were selected as the feeds of steam cracking process and the olefin yields were investigated. In the typical reaction conditions, the normal paraffins in the naphtha contribute most to the ethylene in the products; the iso-paraffins are the main sources of the propylene; the cyclanes mainly produce the butadiene and the aromatics can hardly produce olefins. According to this, the adsorption process and solvent extraction process were adopted to separate the group compositions in naphtha properly to optimize the cracking feeds. The n-paraffins in naphtha were gathered through adsorption process using 5A molecular sieves. The ethylene yield improved by 13% using the desorption oil rich in n-paraffins as the cracking feed. The aromatics and the cyclanes were extracted from the naphtha. Compared with the naphtha, the ethylene and propylene yields of the extraction raffinate oil were 3.0 and 1.5% higher respectively.     

炼油工业:市场的变化与技术对策

经济新常态下,中国主要成品油消费仍呈增长趋势,汽油和煤油刚性需求增长较快,而柴油需求增速大幅减少,市场需求的柴/汽比明显下降。环保压力增大,国Ⅴ柴油标准和国Ⅴ汽油标准相继推出,油品质量升级步伐必须加快。乙烷制乙烯技术的大规模市场化使石脑油蒸汽裂解生产低碳烯烃受到挑战,开发具有竞争力的丙烯生产技术受到关注。面对市场的变化,为更加高效、清洁地利用宝贵的石油资源,为满足市场需求多产汽油和喷气燃料,为提供更具竞争力的丙烯等基本化工原料,炼油研发部门近年来主动积极地开发一系列新的关键技术,包括更高效的固定床渣油加氢技术(RHT)、多产轻质油的催化裂化蜡油选择性加氢与选择性FCC集成技术(IHCC)、第三代催化裂化汽油选择性加氢脱硫技术(RSDS-Ⅲ)、柴油超深度加氢脱硫技术(RTS)、催化柴油加氢裂化生产高辛烷值汽油技术(RLG)、低压喷气燃料加氢RHSS技术、多产化工原料的催化丙烯技术(SHMP)。这些技术或技术组合将对支撑未来炼油工业的发展和应对市场变化发挥重要作用。     

国内外丙烯生产及供需分析

介绍了国内外丙烯增产的发展趋势将由裂解丙烯转向炼厂丙烯为主。分析了聚丙烯、丙烯腈、环氧丙烷生产对丙烯的需求发展 ,认为今后几年世界范围内丙烯供应不会短缺。     

Performance and Commercial Application of the Promoter LCC-A for Maximization of Propylene Yield

1 Introduction Propylene as an important feedstock for organic chemicals is mainly originated from steam cracking and catalytic cracking processes. During the FCC process the propylene content varies with the FCC catalyst and process technology adopted, resulting in significant difference in propylene concentration in the cracked product——LPG. The conventional FCC pro- cess generally gives a propylene yield of around 4%, while the FCC process with maximization of propylene yield can in…     

吸附富集裂解原料中的正构烷烃蒸汽裂解制乙烯效果研究

研究了直馏石脑油、加氢焦化石脑油和天然气凝析油三种裂解制乙烯原料及其通过分子筛吸附分离后相应的富含正构烷烃脱附油的裂解乙烯收率,并考察了裂解反应条件对不同裂解原料的裂解性能的影响。在工业装置典型操作条件下,直馏石脑油及其吸附分离吸余油和脱附油的乙烯收率分别为29.9%,23.0%,41.1%,脱附油的乙烯收率比直馏石脑油增加11.2个百分点,脱附油的三烯总收率比石脑油增加8.6个百分点;对于加氢焦化石脑油和凝析油,其相应脱附油的裂解乙烯收率分别提高11.1和6.5个百分点。石脑油和脱附油裂解乙烯收率和丁二烯收率均随裂解出口温度的升高而增加,丙烯收率基本不随裂解出口温度的变化而改变。     

The Addition of ZSM-5 to a Fluid Catalytic Cracking Catalyst for Increasing Olefins in Fluid Catalytic Cracking Light Gas

Abstract

The second largest source of propylene supplied for petrochemical application is from fluid catalytic cracking (FCC) units. The primary function of the FCC unit has typically been to produce gasoline. However, refiners have been taking advantage of opportunity to produce and recover more propylene from their FCC unit by increasing reaction severity via riser temperature, adding shape selective catalyst, and installing a propylene recovery unit (PRU). At a conventional FCC process propylene exists in the off gas of FCC and it is about 6 wt% of off gas by changing the FCC process parameter quantity of propylene in off gas can be more than 20 wt% by using ZSM-5 additives and increasing temperature The effects of operating parameters, such as reaction temperature, and ZSM-5 as FCC catalyst additive, on the distribution of the product and the yield of propylene were investigated on a bench-scale fluidized bed reactor. It is the aim of this work to perform an overall analysis of the yields and selectivity of hydrocarbons obtained in the vacuum gas-oil conversion over FCC and ZSM-5 catalysts. The effectiveness of ZSM-5 additive in the FCC process was investigated by doing experimental work in a bench-scale setup. The experiment data of off gas analysis showed that vacuum gas oil cracking at high reaction temperatures of 450–550°C increases the yield of propylene. Similar behavior is observed with the addition of 10–25 wt% ZSM-5 additive. The combination of the two effects (high temperature and ZSM-5 addition) makes the FCC unit an excellent source of light olefins for downstream petrochemical units. Higher FCC reactor temperatures (600–650°C) would not have positive effects for increasing propylene yield.     

分离石脑油馏分组成优化乙烯原料

为了改进乙烯原料,提高乙烯收率,分别选取正构烷烃、异构烷烃、环烷烃和芳烃为裂解原料,考察模型化合物的蒸汽裂解产物分布,并分别采用分子筛吸附分离和溶剂萃取两种工艺,提出了可以适应三种目的烯烃产品不同比例需求的裂解制乙烯原料分子生产路线。在典型的裂解工艺条件下石脑油中的正构烷烃对裂解产物中乙烯的贡献最大,异构烷烃是产生丙烯的主要来源,而环烷烃主要生成丁二烯,芳烃很难裂解生成烯烃。通过吸附分离工艺富集石脑油中的正构烷烃,富含正构烷烃的脱附油蒸汽裂解制乙烯收率与不富集石脑油原料相比可提高13%。通过溶剂萃取将芳烃和环烷烃从石脑油中萃出,萃余油蒸汽裂解制乙烯和丙烯收率与未萃取石脑油原料相比分别提高3.0%和1.5%。分子筛吸附分离和溶剂萃取工艺相结合可以显著提高裂解烯烃收率。     

采用BP神经网络预测石脑油裂解烯烃收率

在乙烯裂解工业装置的典型操作条件下,分别选取正构烷烃、异构烷烃、环烷烃、芳烃为裂解原料,考察了这些模型化合物的蒸汽裂解产物分布情况。结果表明,正构烷烃是优质的乙烯裂解原料,乙烯收率为36%~45%;异构烷烃的丙烯收率约为23%,明显高于正构烷烃;环烷烃裂解乙烯和丙烯收率较低,丁二烯收率则较高,为14%~15%;芳烃很难裂解生成烯烃。建立了包含2个隐层的级联前向BP神经网络,以模型化合物和石脑油样本裂解烯烃收率为依据对该神经网络进行训练,确定了模型参数,并对2种石脑油的裂解烯烃收率仿真数据与实验结果进行了对比。结果表明,二者的误差小于1个百分点,该模型可用于预测石脑油裂解的烯烃收率。     

不同种类石脑油的裂解产物分布及收率对比分析

为了对乙烯裂解原料进行优选及优化利用,开展了加氢裂化石脑油、煤化工石脑油、直馏石脑油、柴油加氢石脑油、焦化加氢石脑油的热裂解试验,分别对其裂解产物中乙烯、丙烯、丁二烯、甲烷、抽余C_4、裂解液相产物收率进行了对比分析。结果表明,不同种类石脑油的裂解产物分布和收率存在很大差异。如煤化工石脑油、焦化加氢石脑油裂解多产乙烯,加氢裂化石脑油裂解多产丙烯,直馏石脑油裂解丁二烯收率高达6.11%,焦化加氢石脑油的裂解抽余C_4收率低至2.73%,柴油加氢石脑油裂解液相产物占比高。因此,结合裂解产物收率、原料成本及供应以及烯烃市场形势,合理选择石脑油进行裂解并有效利用其裂解液相产物可大幅降低乙烯生产成本、提升石脑油裂解制乙烯的综合竞争力。     

Optimizing Naphtha Utilization Based on Molecular Scale Management

The technology of separating normal paraffins from naphtha through adsorption using 5A molecular sieves was studied. The separation efficiency of the normal paraffins was above 99.99%. Using the desorption oil as the feedstock of steam cracking, the ethylene yield increased from 29.7-35.0% to 41.4-49.2% compared to that of the naphtha. The research octane number of the raffinate oil reached more than 85 units with an increase of 20 units compared to that of naphtha.     

Commercial Application of CPP for Producing Ethylene and Propylene from Heavy Oil Feed

A new process named CPP (Catalytic Pyrolysis Process) for producing ethylene and propylene from heavy oil feedstock has been developed. The catalyst CEP was specially designed for this process, which has bi-functional catalytic activities for both carbonium ion reaction and free radical reaction, so as to maximize the yields of ethylene and propylene. The commercial trial showed that the yield of ethylene and propylene was 20.37% and 18.23% respectively in maximum ethylene operation with Daqing AR as feedstock, and the yield of ethylene and propylene was 9.77% and 24.60% respectively in maximum propylene operation by using the same feedstock.Compared with steam cracker, the feed cost of CPP is much lower for producing ethylene and propylene.     

Integration and Optimized Utilization of Naphtha Resources

Naphtha is an important raw material for manufacture of clean fuels and ethylene products.However,China is experiencing a serious imbalance between supply and demand of naphtha,due to its rapidly increasing car population and booming ethylene industry,the demand of which cannot be met by the domestic depleting crude oil resources.Focusing on alleviating the above-mentioned naphtha deficit,this paper puts forward an idea suggesting that China's limited naphtha resource should be used reasonably.Naphtha feedstocks with more potential aromatic content should be used in catalytic reforming process to produce clean fuel products,and those feedstocks with more paraffinic content should be used in ethylene production.Meanwhile,industry tests show that the low-valued naphtha byproduct from ethylene plants and the products of secondary processing units at refineries can also be applied so as to extend the naphtha supply for manufacture of cleaner fuels and ethylene derivatives.     

MIP-CGP工艺专用催化剂CGP-1的开发与应用

阐述了生产汽油组分满足欧Ⅲ排放标准并多产丙烯的催化裂化工艺（简称MIP-CGP）专用催化剂（简称CGP-1）的研究开发与工业应用结果。CGP-1催化剂的基质具有良好的容炭性能，使活性组元受到良好保护，其优势作用在第二反应区得以充分发挥，具有更高的氢转移活性和强的汽油小分子烯烃裂化活性。中国石化九江分公司和镇海炼化公司的MIP-CGP工业试验标定结果表明，与常规FCC相比，采用CGP-1催化剂的MIP-CGP技术在生产烯烃体积分数小于18％的汽油组分的同时，丙烯产率达到8％以上。此外，汽油诱导期大幅提高，抗爆指数增加；总液体收率有所提高，干气产率下降，焦炭选择性良好。     

液化气作裂解料的技术经济评估

根据重整液化气和加氢裂化液化气的模拟评价单程裂解收率，利用PIMS生产优化模型对两种饱和液化气作乙烯裂解料的综合收率和经济效益进行了评估。结果表明，在给定条件下．重整液化气和加氢裂化液化气裂解双烯收率都超过了加氢裂化轻石脑油和焦化加氢石脑油。在裂解经济性方面，两种液化气的裂解边际贡献在给定条件下低于两种石脑油。因此重整液化气和加氢裂化液化气在石脑油资源供应不足和液化气市场价格低于石脑油的情况下，可以作为乙烯企业尤其是炼化一体化企业的裂解原料。     

多产清洁汽油和丙烯的FCC新工艺MIP-CGP的应用

对中国石油化工股份有限公司沧州分公司1.0 Mt/a的FCC装置,采用中国石油化工股份有限公司石油化工科学研究院开发的MIP-CGP(Maximizing Iso-Paraffins-Cleaner Gasoline and Propylene)工艺技术进行了改造,装置改造后于2004年6月19日开工.生产标定结果表明:在催化剂活性较低条件下,汽油烯烃体积分数降低到31.9%,下降了14.9百分点;丙烯产率增加了2.97百分点;汽油的辛烷值RON和MON分别增加了1.9和2.0,从而提高了汽油的抗爆指数;汽油中硫含量下降了42.67%;在改善精制汽油性质的同时,还显著提高了总液体产品收率.     

DCC Technology and Its Commercial Experience

DCC is a new technology derived from FCC for propylene production. The propylene yields can reach 23m% with paraffinic feed and around 17m% with intermediate base feed. A portion of DCC cracked naphtha recycled in a commercial unit resulted in a propylene yield increment of 3.5m% at some expense of naphtha. The total BTX in the 75 - 150℃ naphtha fraction was 57. 6v%, in which toluene and xylenes were 21.9v% and 30.3v%, respectively. DCC catalyst consists of a modified mesopore zeolite with pentasil structure for primary product of naphtha range to undergo secondary cracking for producing light olefins. A series of DCC catalysts was formulated for various objectives, such as maximum propylene, maximum isoolefins, and metal tolerance for residual oil processing, etc. Seven commercial units have been put into production since 1990 inside and outside China, in which three of them were revamped from existing FCCUs, and the other four were grassroots units including a 750kt/a unit in TPI Company, Thailand. Currently, the TPI unit is running in full design capacity with about 40m% of atmospheric residual oil in the feedstock. Although the feedstock is much heavier than design, the propylene yield still keeps around the design value. The commercial experiences of some units are presented.