Gas-phase phosgenation reactor and application thereof in synthesis of organic isocyanates

Abstract

The invention provides a gas-phase phosgenation reactor, comprising a reactor body and a mixer body, wherein a cover plate is arranged at the top end of the reactor body, the reactor body is divided by an inner pipe layer, a middle pipe layer and a reactor outer layer into a center chamber, a middle interlayer and an outer jacket, as three passages, from inside to outside, the mixer body comprisesan organic amine and inert gas mixture passage pipe and a mixer lining, the mixer body is passed through the cover plate on the reactor body and positioned in the center chamber of the inner pipe layer of the reactor body, and an annulus is reserved between the outer wall of the mixer body and the inner wall of the inner pipe layer of the reactor body. The mixer herein is divided into multiple independent assembly parts, so that working is safer, simpler and more convenient; the annulus is reserved between the outer wall of the mixer body and the inner wall of the inner pipe layer of the reactor body, so that the gas-phase phosgenation reactor has improved transferring efficiency and higher capacity.

Description

technical field [0001] The invention belongs to the field of reactors, in particular to a gas-phase phosgenation reactor and its application in the synthesis of organic isocyanate. Background technique [0002] In the field of organic isocyanate synthesis, the gas-phase phosgenation reaction process is gradually becoming mature, and has achieved large-scale production in the field of toluene diisocyanate (TDI) and aliphatic isocyanate (ADI). However, as an emerging industrial technology, the gas-phase phosgenation process still has many technical details that need to be improved. The design of the reactor, as the technical core part of the gas phase phosgenation process, still has the following significant problems: [0003] 1. In the gas phase phosgenation reaction process, the core part of the reactor is the mixer installed on its top. In the process of synthesizing organic isocyanates by gas-phase phosgenation reaction process, the reaction is usually forced to stop due...

AI Technical Summary

Problems solved by technology

At the current technical level, the mixer integrates the nozzles of phosgene and organic amines in a small space, resulting in complicated equipment processing, narrow installation space, difficulty in heat tracing, heavy equipment, difficult disassembly and assembly, and equipment Adjustment is not flexible

The entire mixer is often discarded due to a small damage or modification; 3. Since the reactor body is a jacketed tube installed vertically, the jacket contains a large flow of heat-conducting molten salt fluid, and the density of liquid heat-conducting molten salt is relatively high. Large, high-density and large-flow scouring caused the equipment to vibrate continuously, resulting in flow field disturbance in the reaction area and equipment fatigue, and also had a negative impact on production stability; 4. Since the reactor body is a jacketed tube installed vertically , the jacket is a large flow of heat-conducting molten salt fluid, and heat-conducting molten salt usually contains a certain amount of free chlorine (which has a certain corrosive effect on stainless steel), coupled with high-temperature fluid scouring, the problem of local thinning of equipment is more obvious , and the difficulty of detecting the wall thickness in the jacket is relatively large, which has formed a large hidden danger in the long-term operation of the production device; High-power armored electric heating has the problems of large investment, high failure rate, high operation and maintenance costs

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