Comprehensive soda ash producing process and product application thereof

Abstract

The invention relates to the technical field of soda ash production, and especially relates to a comprehensive soda ash producing process and product applications thereof; the process comprises the following process steps: introducing ammonia gas into a saturated sodium chloride solution to prepare ammoniacal brine; introducing carbon dioxide generated in limestone calcination into the ammoniacal brine to generate a mixture of sodium bicarbonate, sodium chloride and ammonium chloride; filtering the mixture to obtain sodium bicarbonate, sodium chloride and ammonium chloride; calcining the sodium bicarbonate to generate soda ash and carbon dioxide, recycling the carbon dioxide; adding sodium chloride fine powder and ammonia gas into the mixed filtrate of ammonium chloride and sodium chloride to generate ammonium chloride and sodium chloride solutions; separating impurities from the sodium chloride solution by a membrane filter, recycling the sodium chloride solution. The process has the advantages of low production cost, high soda ash whiteness, high sodium chloride utilization rate, no water waste or solid waste generation, environment protection, safety, simple processes, full use of geographic advantages in our country, low raw material purchase cost, waste change into things of value, high economic benefits, and good social benefits.

Description

technical field [0001] The invention relates to the technical field of soda production, in particular to a comprehensive soda production process and the application of its products. Background technique [0002] The production of soda ash is currently widely used by trona method and chemical method. The chemical method is divided into Solvay soda method (also known as ammonia soda method) and Hou's soda method (also known as combined soda method). [0003] The trona method is to use the trona raw material containing sodium carbonate as a single component with extremely high purity to concentrate sodium carbonate monohydrate through conventional evaporation, and then calcined to obtain soda ash. In the ammonia-alkali method in the chemical method, due to the low utilization rate of the raw material salt (the utilization rate is only 72% to 74%) in the production process, the rest of the salt is discarded as the waste liquid along with the calcium chloride solution, and the wa...

AI Technical Summary

Problems solved by technology

This method must be equipped with expensive equipment for producing carbon dioxide and synthetic ammonia respectively. The main production process of synthetic ammonia is to pass coal and steam through a gas generator to produce semi-water gas (containing CO 2 , CO, N2, H 2 、H 2 S, etc.); remove the harmful substance H in the semi-water gas through the desulfurization process 2 S: enter the conversion process to convert CO in the gas into CO 2 ; The remaining gas goes through the decarburization process (carbonization of combined alkali or other methods of decarburization) to absorb the CO in it 2 ; the remaining gas is mainly H 2 and N 2 , and a very small amount of CO, CO 2 and other harmful gases, and then remove the harmful substances through the purification process, so that the content is controlled below 10PPM, and the pure H 2 and N 2 Then through the synthesis process, synthetic ammonia (NH 3 ), large investment costs, high energy consumption in synthetic ammonia plants, and inability to make full use of my country's geographical advantages. The purity of the carbon dioxide produced is low (generally about 28%), and waste gas is produced, causing great environmental pollution and low production safety.

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