Method for recycling ammonia from raw morpholine

Abstract

A method for recycling ammonia from raw morpholine comprises the steps: raw morpholine is adopted as a raw material and is continuously pumped into a deamination tower which adopts steam from a reboiler for heating; due to lower boiling point of ammonia, an ammonia collecting valve at an outlet is used for controlling pressure which is set to be within a range between 1.1 and 1.3 MPa; various temperature levels in the deamination tower are maintained, the condensate at the top of the tower is reflowed so as to form circulation; one part of the condensate is used for alternating with heavy components, transferring mass and heat in the tower and preventing the heavy components from moving upward and blocking fillers, and the other part thereof is collected by the ammonia collecting valve, thus completing the recycling of ammonia. The method adopts internal pressurization and rectification to raise liquefaction temperature of ammonia so as to realize ammonia recycling rectification operation which adopts flash evaporation as a heat resource. The method has advantages: the process is simple; normal equipments are adopted; the purity of ammonia which is recycled by adopting self-warming steams inside the ammonia tower and primary and secondary distributing method is extremely high and reaches to 90 percent CW; and the method has less side reactions impacting morpholine reaction and being applicable to recycling in preparation.

Description

Technical field: [0001] The invention belongs to the technical field of morpholine production, and in particular relates to a method for recovering ammonia in a crude morpholine production process. Background technique: [0002] Morpholine, also known as 1,4 oxazidine, molecular formula C 4 h 9 NO, is a colorless oily liquid, hygroscopic, strongly alkaline, with ammonia odor, miscible with organic solvents, insoluble in strong alkali solutions, flammable, and is an important organic synthesis reagent. It is mainly used as the raw material of rubber accelerator NOBS, OTOS, etc. It is also widely used in medicine, textile, paint and other industries. [0003] According to national standards, the preparation of morpholine uses ammonia with a purity of 99% as raw material, and diethylene glycol liquid ammonia and hydrogen enter the reactor after being heated and vaporized. Under high temperature and high pressure, the gas-solid phase catalytic amination reaction is carried o...

AI Technical Summary

Problems solved by technology

[0007] In addition to morpholine, N-ethylmorpholine, water, etc. in crude morpholine, there are about 35% NH 3 , because the boiling point of ammonia is -33.5°C, it is difficult to achieve it by normal pressure recovery method

[0008] At present, some units adopt the method of flash evaporation, and then the ammonia deammonization refrigerator or compressor of the flash evaporation, there are two disadvantages in this method: one is that the ammonia flash evaporation in the crude morpholine is not complete, and the water in the dehydration tower Wastewater from gas generation is exposed to the atmosphere through cooling tower fans, which wastes resources and pollutes the environment

Second, gas ammonia to refrigerators or ammonia compressors consumes a lot of power consumption

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