Dehydration process and dehydration device for crude aniline

Abstract

The invention discloses a dehydration process and a dehydration device for crude aniline. The method comprises the following steps: a) crude aniline is produced in a reactor, the side temperature of the reactor is 210-220 DEG C which is lower than the traditional operation temperature, and the moisture content of the crude aniline is preliminarily reduced; b) the crude aniline is subjected to air cooling and water cooling through an air cooler and a water cooler respectively, the power of the air cooler is fully opened, circulating water of the water cooler is fully opened, crude dehydrated crude aniline is obtained after passing through a decantation tank, and the crude dehydrated crude aniline enters a crude aniline tank; the temperature in the decantation tank and the crude aniline tank is 30-40 DEG C; and c) feeding the crude dehydrated crude aniline into a catalyst thickener and a dehydrating tower, and carrying out thickening dehydration to obtain the aniline, with the negative pressure of the dehydrating tower being 39.0-42.0 kPa, the tower top distillate being 3900-4100 Kg / h, the sealing liquid medium of the catalyst thickener and the dehydrating tower being aniline, and the sealing water flow of the catalyst thickener being 40-60 L / h. The method can effectively reduce the moisture content of the crude aniline before refining, improve the efficiency of the dehydrating tower, ensure the safe operation of the process, and greatly reduce the moisture content of the aniline finished product to reach a superior level.

Description

Technical field [0001] The present invention relates to the technical field of aniline production process, specifically to a crude aniline dehydration process and dehydration device. Background [0002] Aniline, also known as anillin, anillin oil, aminobenzene, molecular formula is C6H7N, colorless oily liquid, slightly soluble in water, soluble in ethanol, ether and other organic solvents; aniline is one of the most important amine substances, mainly used in the manufacture of dyes, drugs, resins, but also as rubber vulcanization promoters, etc., it itself can also be used as a black dye, the use is very extensive. [0003] Aniline mainly using nitrobenzene hydrogenation reduction method to produce, specifically, in the fluidized bed reactor, electrolytic table brine produces hydrogen, after purification by NaOH solution, cyclone separation, activated carbon adsorption, etc., heating into the evaporator, while nitrobenzene metering added to the evaporator and hydrogen mixing, m...

AI Technical Summary

Problems solved by technology

[0003] Aniline is mainly produced by the hydrogenation reduction method of nitrobenzene. Specifically, in the fluidized bed reactor, the electrolysis of salt water produces hydrogen, which is purified by NaOH solution, cyclone separation, and activated carbon adsorption. Then, it is heated and enters the evaporator. Nitrobenzene is metered into the evaporator and mixed with hydrogen. The mixed gas enters from the bottom of the fluidized bed and reacts with the silica gel copper catalyst in the bed; the generated crude aniline and water vapor are discharged from the top of the bed, cooled and separated by the crude aniline condenser, The finished product is obtained by rectification; the aniline obtained according to this process often has high moisture content and cannot reach a high-quality level, so the market competitiveness of the product is weak and the expected effect cannot be achieved

Images