Comprehensive utilization method of sulfamic acid production waste acid

Abstract

The invention discloses a comprehensive utilization method of a sulfamic acid production waste acid. The method comprises the following steps: uniformly mixing an aluminum-containing material with thesulfamic acid production waste acid, pumping into a reaction kettle, heating to 90-150 DEG C to initialize a reaction, controlling the pressure intensity to 0-0.4MPa in the reaction, after the reaction is completed, adding water to dilute the content of aluminum oxide in the reaction liquid obtained in the reaction to 8.1-8.3wt%, filtering to obtain a mixed solution of aluminum sulfate and ammonium alum, pumping into a crystallizer, cooling and crystallizing, carrying out solid-liquid separation, and drying the obtained solid to obtain a product, namely ammonium alum, and a liquid, namely analuminum sulfate solution, wherein the aluminum-containing material is bauxite or aluminum hydroxide; when the aluminum-containing material is bauxite, the mass ratio of the bauxite to the sulfamic acid production waste acid is 1:(1.44-2.88); when the aluminum-containing material is aluminum hydroxide, the mass ratio of the aluminum hydroxide to the sulfamic acid production waste acid is 1:(3.07-3.69). The method is capable of recycling and obtaining a great deal of ammonium alum and aluminum sulfate, and has the advantages of being high in recycling rate, low in cost and simple in steps.

Description

technical field [0001] The invention relates to the technical field of waste liquid recovery, in particular to a method for comprehensive utilization of waste acid from sulfamic acid production. Background technique [0002] Ammonium alum is a double salt of ammonium sulfate and aluminum sulfate containing crystal water. It can be used in water purification, paper sizing, paint printing and dyeing, aquatic product pickling, pharmaceuticals, leather, rubber and colored glass industries. Its existing production methods It is obtained by mixing and reacting ammonium sulfate and aluminum sulfate, crystallization and separation. Due to its wide range of uses, the social demand is relatively large, and ammonium sulfate and aluminum sulfate are relatively in short supply in the market now, thereby causing the output of ammonium alum to be unable to meet market demand well. [0003] Sulfamic acid is an important fine chemical product, which is widely used in cleaning agents, polish...

AI Technical Summary

Problems solved by technology

In view of the fact that sulfamic acid production waste acid contains a certain proportion of sulfamic acid and ammonium bisulfate, if it is used to produce industrial sulfuric acid, its quality will not meet the requirements

Therefore, the current method of utilizing waste acid from sulfamic acid production is usually to use it to neutralize alkaline wastewater. Because the waste acid from sulfamic acid production contains a large amount of ammonium bisulfate, a large amount of ammonium bisulfate is brought into the waste water after treatment. The direct discharge of ammonia nitrogen will cause eutrophication of water body, black odor of water body, and damage to the ecological environment. It is necessary to increase the process of removing ammonia nitrogen, which will obviously increase the cost and prolong the production cycle, and the economic benefit is not good.

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