【作者】 董艳丽；

【导师】 王延臻；

【作者基本信息】 中国石油大学 ， 化学工程与技术， 2011， 硕士

【摘要】 目前我国轻质燃料油需求急速增长,同时原油的重质化以及催化剂的磨损给催化裂化装置带来结焦、结垢等不利影响,严重影响产品的质量及产品的分布,并且由于油浆的不合理利用,造成了很大浪费。因此研究催化油浆中催化剂颗粒的脱除工艺以及催化油浆的组分分离及合理利用具有重要的现实意义。本论文选用胜华催化油浆、兰州石化催化油浆为研究对象,主要采用化学沉降助剂降低油浆中催化剂颗粒的含量,确定脱除工艺,并对脱除机理进行初步探讨;提出了以糠醛作为萃取溶剂,用催化裂化油浆生产环保型橡胶填充油和催化裂化原料的观点,通过单级、多级错流萃取实验和多级逆流萃取实验,考察萃取温度、萃取剂油比和萃取级数的影响。通过对沉降助剂进行筛选,若选用聚丙烯酰胺水溶液作为沉降助剂,聚丙烯酰胺加入量为250μg/g,于80℃沉降30min时,催化剂的脱除率可达87.5%;若选用体积分数为50%的丙三醇水溶液作为沉降助剂,加入量为油浆总量的60%,于80℃沉降30min,循环利用丙三醇水溶液三次,催化剂的脱除率仍都在80%以上;若选用LAL-2作为沉降助剂,当加入量为200μg/g,于80℃沉降24h时,催化剂的脱除率可达95.2%。初步认为本实验所选用的沉降助剂对催化剂颗粒脱除主要与沉降助剂本身的粘度以及分子结构有关。脱除催化剂颗粒后的油浆分别采用糠醛萃取和反萃取方法来进一步对油浆组分进行分离,将油浆中的多环芳烃与饱和烃分离。研究了错流萃取和逆流萃取两种实验方案,确定单级错流萃取实验的最佳条件为:萃取温度为50℃,剂油比为2.5:1;根据原料油性质不同,萃取工艺级数为二级时最优;反萃取工艺级数为三级时最优。经过萃取分离得到的饱和烃可作为催化裂化的原料返回催化裂化,也可作为环保型橡胶油使用;多环芳烃由于裂化性能很低,可作为橡胶填充油或其他用途。这样催化裂化油浆可以不直接循环而是先溶剂萃取分离出易裂化组分和难裂化组分,易裂化组分返回催化裂化,难裂化组分作为别的用途使用,这样可以减少催化裂化结焦,提高催化裂化的液收。更多还原

【Abstract】 At present, the needs of light fuel oil have been growing rapidly in China, meanwhile the heavy crude qualitative and catalyst cracking bring coking, fouling and other adverse effects to FCC, so that the devices could not be function properly, and this seriously affected the quality of products and product distribution. What’s more, the irrational use of FCC slurry caused a great of waste. Therefore, the research of effective removal of catalyst particles technology and rational use of FCC slurry had important significance.This paper choose Shenghua and Lanzhou FCC slurry as the research objects, using the chemical additives to reduce the content of catalyst particles in the slurry oil, and study the removal process, then discuss the removal mechanism. It is proposed that using the furfural as the solvent in FCC slurry oil system could product the environmental-friendly rubber filling oil and FCC feedstock. One-stage extraction, multi-stage cross-flow extraction and multi-stage countercurrent extraction experiments were designed to study the effects of extraction temperature, the ratio of solvent to oil and the series of extraction.If polyacrylamide solution were used to remove the solid catalysts from FCC slurry, the best reaction conditions were that: the addition of polyacrylamide was 250μg/g, stirring at 80℃for 30 minutes, the removal ratio of catalyst particles could reach 87.5%; If 50% volume fraction of glycerol solution were used to remove the solid catalysts from FCC slurry, the best reaction conditions were that: the addition of glycerol solution was 60wt% of the slurry, stirring at 80℃for 30 minutes, The glycerol solution was washed, filtered and concentrated to achieve recycling, then the third removal ratio of catalyst particles could still reach more than 80%; If LAL-2 were used as chemical additives to reduce the content of catalyst particles, the best reaction conditions were that: the addition of LAL-2 was 200μg/g, stirring at 80℃for 30 minutes and resting for 24h, the removal ratio of catalyst particles could reach 95.2%. It could be obtained that the main effect of the catalyst particle removal was related to the viscosity and molecular structure of settlement agents.The FCC slurry was separated further into saturation fractions and aromatic fraction by using furfural extraction. Cross current extraction and counter-current extraction were studied in this dissertation. The best extraction conditions in primary cross current solvent extraction were that: reaction temperature was 50℃, and the ratio of solvent/oil was 2.5:1. In the extraction process series, the optimal series was twice. In the solvent stripping process level 3 was the optimal series. Then in simulation experiments on three counter-current extraction, when the reaction temperature was 50℃, the ratio of solvent/oil was 2.5:1, and the extraction series was three, the product conforms to the Europe standard requirements, and the yield could reach 30%.The saturation fractions could be the raw materials of FCC unit. The aromatic fraction could be used as the rubber oil because of its poor property of cracking. Thus, the FCC slurry was first extracted into easy cracking fractions and difficult cracking fractions instead of recycling straight into FCC. The easy cracking fractions were recycled into FCC and the difficult cracking fractions are used as rubber oils. This method may lower the coke quantity of FCC and improve e the production of liquid products.更多还原