Reactor and method for preparing propylene by method of group feeding of heavy oil and light olefin

Abstract

The invention discloses a riser reactor for preparing propylene, which comprises an upper section of pipeline and a lower section of pipeline. The upper section of pipeline is a straight pipe, while the lower section of pipeline is a diameter expanding section, of which the shape is of a pipeline of a round table; and an included angle between a bus and an axis of the round table is 1 to 60 degrees, wherein the diameter of the upper bottom surface of the round table is more than or equal to that of the straight pipe. The reactor is adopted for preparing the propylene by a method of group feeding of heavy oil and light olefin by catalytic cracking; and the axial average air speed in the straight pipe on the upper section of the riser is 3 to 25m / s, the axial average air speed in the diameter expanding section is 0.1-5m / s, the exit temperature of the riser is between 460 and 600 DEG C, and the light olefin accounts for no more than 50 percent weight of the raw oil, so that the yield andthe selectivity of the propylene are improved, and the reactor and the method can be used for the production of diesel oil and high-octane petrol.

Description

technical field [0001] The invention relates to a method for preparing propylene, in particular to a method for preparing propylene by catalytic cracking combined feed of heavy oil and light olefins and taking diesel oil and high-octane gasoline into account. Background technique [0002] Propylene is an important basic organic chemical raw material, and its production routes include steam cracking of naphtha, catalytic cracking of heavy oil, dehydrogenation of propane, and metathesis reaction of ethylene and 2-butene, etc. From the perspective of propylene production, naphtha steam cracking contributes the largest amount of propylene, followed by heavy oil catalytic cracking, propane dehydrogenation and ethylene-2-butene metathesis contribute little propylene. [0003] The production of propylene by naphtha steam cracking mainly has the following disadvantages: shortage of high-quality cracked naphtha resources, high energy consumption, low propylene / ethylene ratio and low ...

AI Technical Summary

Problems solved by technology

[0003] The steam cracking of naphtha to produce propylene mainly has the following disadvantages: shortage of high-quality cracked naphtha resources, high energy consumption, low propylene / ethylene ratio and low yield of high value-added products

However, the realization of ultra-short reaction time is very difficult in engineering

At present, the TMP industrial device controls the contact reaction time of C4 olefins and light gasoline with the catalyst alone to 0.3-0.5s. To further reduce the reaction time, there are two measures: shorten the height of the reactor for the separate reaction part of light feed, and the space is too small to Relevant equipment is arranged, and the fluidization of the catalyst is extremely uneven; increasing the linear velocity of the gas will cause a decrease in the fluidization density of the catalyst, affecting the contact between oil and gas and the catalyst, thereby affecting the reaction effect

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