System for preparing sodium carbonate and baking soda as byproducts boric acid and ferric hydroxide from trona liquid

Abstract

The invention discloses a system for preparing sodium carbonate and baking soda by-products boric acid and ferric hydroxide from a trona solution. The system comprises a sodium carbonate preparation unit, a boric acid byproduct unit, a ferric hydroxide byproduct unit and a baking soda preparation unit. The system has the following advantages that boric acid ions and iron ions in the natural alkali liquid are adsorbed through the boron ion exchange resin and the iron ion exchange resin respectively, and the content of iron and boron in the raw material liquid is reduced, so that the content of boron and iron in sodium carbonate and baking soda products is reduced, and the superior rate and quality of the products are improved; by further treating the washing liquid after the ion exchange resin column elution, the byproducts of ferric hydroxide and boric acid are prepared.

Description

Technical field: [0001] The invention relates to a system for producing soda ash and baking soda from natural lye, in particular to a system for producing soda ash and baking soda from natural lye by-product boric acid and ferric hydroxide. Background technique: [0002] At present, ammonia soda method, combined soda method and trona method are mainly used in the production of soda ash and baking soda. Among them, the ammonia soda method and combined soda method use sodium chloride as raw material, and the semi-finished product is calcined to obtain soda ash, and the soda solution is carbonized to obtain baking soda. Product, because the purity of raw material salt is higher and less impurity, so the impurity content of product is relatively stable. [0003] The trona method is used to produce soda ash and baking soda, which uses underground trona mines as raw materials. Trona mainly exists in underground trona mines and trona lakes. The main component of underground trona m...

AI Technical Summary

Problems solved by technology

[0005] In the process of producing soda ash and baking soda by the trona method, since the underground trona ore contains a small amount of impurity elements such as boron and iron, the evaporation and concentration of the raw material solution during the soda production process will cause the accumulation of iron and boron in the lye to increase. In addition, equipment corrosion is also the main reason for the increase of iron content in lye. Natural lye contains a large amount of sodium bicarbonate, and iron ions mainly exist in divalent form, and the solubility of ferrous iron is high. The iron content reaches 60mg / l. The iron content in soda ash and baking soda products is relatively high, and the rate of superior products decreases, which has a certain impact on product quality

The boron content in the soda filter mother liquor reaches 600mg / l, which has a certain impact on product quality

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