Sorting Method of Separation Media in Fluidized Bed Separator

Abstract

The disclosure relates to a separation medium sorting method in an ebullated bed separator, the method comprising: setting a cyclone on the upper part of the ebullated bed separator, during regeneration, the separation medium in the filter bed of the ebullated bed separator is in a fully fluidized state, The separation medium enters the cyclone upwards. After being sorted by the cyclone, it flows out of the cyclone in descending order according to the specific gravity. After the backwash regeneration is completed, it continues to be used for the purification of process water generated in the MTO process. Among them, the ebullated bed separator The filter bed is composed of multiple layers of different separation media, the particle size distribution of the separation media decreases layer by layer downward, and the specific gravity of the separation media increases layer by layer downward.

Description

technical field [0001] The present disclosure belongs to the technical field of coal chemical process water treatment, and in particular relates to a method for selecting, sorting and size grading of separation media in an ebullated bed separator, which is suitable for an ebullated bed separator for treating process water in a methanol-to-olefin process Removal and concentration of oil wax and particulate matter. Background technique [0002] Methanol to olefins, referred to as MTO (Methanol to Olefin), refers to the process of preparing low-carbon olefins by catalytic reaction using methanol as a raw material. In the industrial production of MTO, the reaction gas generated from the reactor carries worn catalyst particles and oil substances. After being separated by the three-stage cyclone separator, the reaction gas will also entrain a part of catalyst and oil substances into the quenching tower, After being cooled and washed by the quenching tower and the washing tower, t...

AI Technical Summary

Problems solved by technology

However, due to the characteristics of the precision filtration device itself, the pressure difference of the precision filtration device rises rapidly during the process of treating the quench water from methanol to olefins, and the backwashing is not thorough, so it cannot be put into normal use, resulting in the inability to effectively remove fine particles and accumulate in the system , so that the solid content balance value in the quenching water system is as high as 500-1000mg / L, resulting in severe blockage of the heat exchanger and air cooler in the quenching water system, and insufficient heat transfer efficiency, which requires frequent cleaning of the heat exchanger, which greatly increases system maintenance. cost, affecting the long-term operation of the device

[0004] Chinese patent application 201410173205.X discloses that the treatment method is to filter the quenching water and washing water through the ultrafiltration membrane to obtain the treated clear liquid and return it to the system for reuse. High, the main problem to be solved should be to reduce its solid content, and ultrafiltration membrane filtration is precision filtration, with small permeation flux and small processing capacity, which cannot meet the actual industrial application. At the same time, the particle size of the catalyst is small, and the solution can be directly filtered Clogging the filter holes, causing the filtration pressure to increase instantaneously and terminate the filtration

Chinese patent application 20101053902.3 proposes micro-swirl separation of MTO quenching water using micro-swirl technology to remove catalyst particles entrained in it; micro-swirl separators can separate fine particles below 3 μm, especially very fine particles below 1 μm The problem of limited efficiency, and because of its structural characteristics, it is easy to cause clogging, low separation accuracy, incomplete catalyst recovery, high pressure drop and other problems, which increase the energy consumption output and the difficulty of cleaning and maintenance in the later stage

Chinese patent application CN 205031975 U discloses a device that uses sintered metal to filter MTO quenching water, and regenerates the filter element by backflushing and chemical cleaning; the disadvantage is that the sintered metal has small voids, and the catalyst particles in the quenching water are easy to block Pores, using chemical cleaning to produce a large amount of chemical waste liquid, the cost of post-processing is high, and it will corrode the filter element, which needs to be replaced regularly, which is expensive and maintains high

[0005] Therefore, in order to solve the problem that fine particles and oily substances are difficult to remove in the process water of the methanol-to-olefins plant in the prior art, it is urgent to develop a method for selecting, sorting, and grading the separation medium in the ebullated bed separator to Separation of fine particle pollutants in the cooling water of the methanol-to-olefins process, reducing the frequency of heat exchanger cleaning, and realizing long-term stable operation of the methanol-to-olefins unit

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