Method for recovering ammonia in morpholine solution

Abstract

The invention discloses a method for recovering ammonia in a morpholine solution. The method comprises the following steps of: continuously pumping the morpholine solution serving as a raw material into a deamination tower above 30 percent of a tower kettle liquid level from a feeding hole on the middle upper part of the deamination tower through a feed metering pump; hanging a communicated re-boiling heater outside the deamination tower; heating a liquid in the tower by using steam; heating and gasifying ammonia in the morpholine solution according to the physical property of low boiling point of ammonia; condensing a part of gasified ammonia into liquid ammonia in a rising process in the tower; continually raising the remaining un-liquefied gas ammonia to a tower top, and feeding into a tower top condenser through a tower top gas-phase pipeline for condensing into liquid ammonia; continuously feeding to continuously form inverse flow of tower top condensate (liquid ammonia); and circulating repeatedly to complete recovery of ammonia. The liquefying temperature of ammonia is raised with an internal pressurization distillation method, so that ammonia recovery and distillation operation taking flash evaporation as a heat source is realized.

Description

Technical field: [0001] The invention belongs to the technical field of morpholine production, and in particular relates to a process for recovering ammonia in a morpholine solution. Background technique: [0002] Morpholine, also known as 1,4 oxazidine, molecular formula C 4 h 9 NO, a colorless oily liquid, hygroscopic, strong alkaline, amine smell, miscible with organic solvents, insoluble in strong alkali solutions, flammable, is an important organic synthesis reagent, mainly used as a rubber accelerator NOBS , OTOS and other raw materials. At the same time, 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. Diethylene glycol liquid ammonia and hydrogen enter the reactor after being heated and vaporized. At a specific temperature and pressure, the gas-solid phase catalytic ammonolysis and cyclization reaction is carried out t...

AI Technical Summary

Problems solved by technology

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

[0008] At present, some manufacturers use the method of flash evaporation, and then flash the ammonia deammonization refrigerator or compressor. There are two disadvantages in this method: one is that the ammonia flash evaporation in morpholine is not complete, and it will be discharged into the waste water with the follow-up section Sewage treatment pools are exposed to the atmosphere, which wastes resources and pollutes the environment; secondly, gas ammonia is converted into liquid ammonia by refrigerators or ammonia compressors, which consumes a lot of electric energy and increases production costs

Images