Fluidized bed polymerization reactor

Abstract

A fluidized-bed polymerizing reactor is composed of enlarged top segment, cylindrical reaction segment, gas distributing plate, and gas mixing chamber with one or more gas guiders which consists of ring plate, inverse hollow ring conical table and central striker. Its advantages are low impact of central gas stream to distributing plate, high running stability, high output rate, and long service life.

Description

technical field [0001] The present invention relates to fluidized beds, in particular to fluidized bed polymerization reactors. Background technique [0002] When using a fluidized bed reactor for exothermic polymerization, the reaction rate should be limited so that the released heat can be transferred from the fluidized bed in time to prevent failures in the fluidized bed. One way to increase the rate of reaction heat transfer is to compress and cool the monomeric gas required to be recycled back to the reactor so that it is partially condensed. The resulting liquid is entrained by the recycled monomer gas stream and returned to the reactor. This is known as "condensation mode" polymerization operation and is disclosed in U.S. Patent Nos. 4,543,399 and 4,588,790 to Jenkins et al., which state that this "condensation mode" operation reduces the temperature of the recycle gas stream, and Since the evaporation of the liquid absorbs heat, the combinat...

AI Technical Summary

Problems solved by technology

[0005] 1) Uneven gas distribution

The air flow in the center of the annular deflector is too large and the speed is too fast. The circulating flow and its entrained powder and liquid directly impact on the bottom surface of the distribution plate. Under the action of high-speed flow, it enters the distribution hole and causes blockage

However, in the bottom annular area about 500mm radially inward from the outer periphery of the distribution plate, the flow rate decreases, and powder is often deposited, resulting in blockage of the distribution plate area.

[0006] 2) Deposition of powder, easy to flake

[0009] After practice, such a method still has the following disadvantages: if the liquid film and liquid block content from the delivery pipeline are high, that is, the liquid holdup rate is high, a "liquid roll" may be formed in the center hole of the third air flow, and the liquid block and liquid block The roll is further dispersed and entrained by the airflow in the sidewall channel during the falling process. The droplets produced by this redispersion are usually relatively large, and most of them move upward in the form of droplet clusters, which easily leads to the phenomenon of dripping rain in the mixing chamber. , it is also easy to cause sharp holes in the local area of ​​the distribution plate to form geysers

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