A method for refining ammonia-containing methanol waste liquid

Abstract

The invention discloses a refining method of an ammonia-containing methanol waste liquid, the refining method comprises the following steps: (1) inputting of the ammonia-containing methanol waste liquid into a distillation tower; (2) total reflux of the distillation tower; (3) use of an acid pickling tower for absorption of volatilized ammonia in the distillation column and preparation of the ammonia into an ammonium sulfate solution, after the acid pickling tower is saturated by absorption, preparation of a crude ammonium sulphate product from the ammonium sulfate solution by ammonium sulfate drying dehydration equipment; (4) addition of sulfuric acid in the distillation column after the total reflux for neutralization; (5) total reflux of the distillation tower and control of the reflux ratio to 3-10 for direct distillation of the methanol waste liquid in the distillation tower into a high purity methanol finished product, and (6) final discharge of a tower bottom liquid released from the bottom of the distillation tower. The process of the method is simple, and the cost is greatly reduced.

Description

technical field [0001] The invention relates to the field of resource recovery and utilization in the environmental protection industry, in particular to a method for refining ammonia-containing methanol waste liquid. Background technique [0002] Aniline is one of the important amine substances, mainly used in the manufacture of dyes, drugs, resins, and can also be used as a rubber vulcanization accelerator. The industrial production methods of aniline mainly include nitrobenzene iron powder reduction method, chlorinated animination method, nitrobenzene catalytic hydrogenation reduction method and phenol ammonia solution method. At present, the hydrogenation reduction method of nitrobenzene is the main production method. [0003] Nitrobenzene hydrogenation reduction method requires the participation of methanol solvent in the process of nitrobenzene hydrogenation, and ammonia gas is generated and dissolved in methanol. In the refining process of aniline, methanol, ammonia...

AI Technical Summary

Problems solved by technology

The first is direct rectification, but it will produce a lot of ammonia smell, and there is still a small amount of ammonia residue in the methanol product, which makes the methanol product alkaline and difficult to sell again

The second is to add acid to neutralize to acidity, and then rectify, which results in a large amount of acid addition and a large amount of liquid at the bottom of the tank, which increases the cost

The third type is directly sent to the incinerator for incineration, and the incineration price is 6000-8000 yuan / ton, which causes waste of resources and increases the cost