Abstract:

The filtration slurry purification technology has a development history of nearly 40 years, but the problems of filter frequent switching and cannot run for a long term have not been solved. It is proposed that the enrichment of “agglomerates” formed by catalyst fine particles and colloid/asphaltene in slurry is the cause of mutational site of pressure drop of the filter and easy to cause plugging. Based on the existing filtering equipment, it's the first time of the slurry purification system was developed by improving the properties of the slurry, and the industrial application technology schemes of slurry purification system + filter and slurry purification system + settling tank + filter were formed. The industrial application results show that the annual output of tricyclic and tetracyclic aromatic hydrocarbons increases from 19.3 kilotons to 30.5 kilotons, with an increase of 58.0%. The operation time of the filter is increased by more than 2.5 times, and the washing time is controlled within 5 minutes. The system can operate for a long period, meeting the requirements of the downstream device for particle content. Adopting the scheme of slurry purification system + settling tank + filter, the content of catalyst particles can be controlled steadily below 5 μg/g, meeting the strict requirements of slurry utilization. The slurry purification system has completely solved the above problems and realizes the efficient removal of fine particles of slurry catalyst.

Key words: FCC, slurry purification system, filter, filter residue, high value fraction, fine particle content, stable and efficient operation

摘要：

过滤法油浆净化技术具有近四十年的开发历史，但过滤器切换频繁、无法长周期运行的问题至今仍未解决。提出了油浆中催化剂细颗粒和胶质/沥青质形成的“团聚物”在滤芯上富集是导致过滤器进出口压差突变，进而造成滤芯堵塞的原因。基于现有的过滤设备，首次从改变油浆性质入手，开发了油浆净化系统，形成了油浆净化系统+过滤器、油浆净化系统+沉降罐+过滤器的油浆净化工业应用技术方案。工业应用结果表明：该系统使三环和四环芳烃组分年产量从19.3 kt提高到30.5 kt,增幅58.0%,过滤器运行时间提高2.5倍以上，反冲洗时间控制在5 min以内，且能够长周期运行，满足下游装置对颗粒物含量的要求。油浆净化系统+沉降罐+过滤器的方案可控制催化剂颗粒物质量分数长期稳定在5μg/g以下，满足油浆利用更苛刻的要求。油浆净化系统彻底解决了目前油浆过滤装置面临的切换频繁、无法长周期运行的难题，实现了油浆催化剂细颗粒高效脱除。

关键词: 催化裂化, 油浆净化系统, 过滤器, 滤渣组成, 高价值馏分, 细颗粒含量, 平稳高效运转