【作者】 姜升；

【导师】 吴嘉；

【作者基本信息】 浙江大学 ， 化学工程， 2005， 硕士

【摘要】 随着原油的日益重质化和市场对重质燃料的需求日益减少,近二十年裂化原料中掺渣比例不断提高,重油的催化裂化发展很快。同时,国家对环保要求日趋严格,对清洁燃料需求量不断增加,也给炼油催化剂工业发展提出了新的挑战。为了适应这种需要,要求催化裂化催化剂要具有更高的性能。 超稳Y型分子筛是催化裂化催化剂的主要活性组分,其改性工艺对催化剂的重油裂解能力、水热稳定性、及产品的选择性等都有关键性的影响。 我厂的超稳分子筛装置近年来运用了一些新工艺:带式滤机取代板框滤机,进行分子筛的二次过滤交换洗涤,简化了流程,实现了连续生产,提高了产品收率和原料利用率;采用喷雾干燥工艺生产超稳分子筛,取得了以下效果:一是传热好,干燥速率快,提高了装置的利用效率,出口物料固含量稳定;二是利用焙烧炉烟道尾气作热源,提高了能源的利用率。但是这些新工艺在使用过程中也带来一些问题:带式滤机进行二次过滤交换洗涤,主要存在过滤速度慢,Na₂O不稳定的问题;喷雾干燥主要带来晶胞常数不收缩、分子筛粒度大的问题。本课题根据过滤和喷雾干燥的机理,结合分子筛合成和改性的研究,通过实验提出了对两种新工艺的改进措施,探讨了其对生产和质量的影响,使新工艺成功应用于超稳分子筛生产。更多还原

【Abstract】 While crude oil is heavy-oriented and market demand of heavy fuel decreases, the ratio of resid blended feedstock increases continuously, and resid catalytic cracking technology also develops rapidly. Meanwhile, the deepening strict of national environmental requirements and the increasing demand of clean fuel also brings new challenges to the development of refinery industry. For the purpose of adapting to this requirement, better performances of catalytic cracking catalyst are needed.Ultrastable Y zeolite is the major active components of catalytic cracking catalyst, and its modification process can produce some key effects on the ability of resid cracking, hydrothermal stability, and product selectivity of catalyst.Some novel technologies have, been employed for the production of ultrastable Y zeolite in my plant in recent years. In the second filtration step, ion-exchange and scrubbing of zeolite are carried out with a belt filter instead of the traditional plate-and-frame filter press, so that the production process is simplified, the continuous production is implemented, and the yield and utilization ratio of raw materials are improved. The technology of spray drying is adopted in zeolite drying step, which has the following advantages: firstly, heat transfer is improved to obtain a faster drying rate, a higher efficiency of equipment and a stable solid content of the output materials; secondly, the energy efficiency is improved through the utilization of roasting furnace exhaust as heat resources. However, these novel technologies also resulted in two main problems: one was that the rate of the second filtration, exchange and scrubbing in the belt filter was slow, and the Na₂O content in zeolite was not stable: the other is that the cell constants did not contract and the particle size of zeolite was bigger in spray drying. In combination with the research of zeolite synthesis and modification, this subject elaborates the effects of ultrastable Y zelolite on performance of catalytic cracking catalyst. Based on the mechanism of filtration and spray drying process, this work proposed some improvements, by experiments in combination with the work of zeolite synthesis and modification, explored the influences of the improvements on production and quality, and made the new technologies implemented successfully in the production.更多还原