Preparation method for producing refined salt by gas hydration and dehydration

Abstract

The invention relates to a preparation method for producing refined salt by gas hydration and dehydration. The method comprises the following steps of: feeding brine into a hydration reactor to generate hydration reaction with small molecular gas such as liquefied gas to generate ice-like gas hydrate crystals, and separating out sodium chloride crystals; making the gas hydrate crystals resolved in the resolving tower, wherein the separated liquefied gas is recycled, and the separated water can be used for salt dissolving to prepare brine; and centrifugally dewatering and drying the separated sodium chloride crystal to obtain the product refined salt. Compared with the prior art, the method has the advantages that vacuum evaporation operation is not needed, and energy consumption is low; and hydrate generation and salt precipitation are completed in one set of equipment, the technological process is simple, the equipment requirement is low, and the fixed asset investment is small.

Description

technical field [0001] The invention relates to a method for producing salt. Background technique [0002] Most of China's edible salt is processed and produced with refined salt as the base salt, and the production of refined salt is generally prepared by dissolving salt to make brine, refining brine, and vacuum evaporation. Among them, the vacuum salt making technology has been developed to adopt the most advanced five-effect vacuum evaporation technology. The five-effect vacuum evaporation production process can be divided into four types: co-current (downstream), countercurrent, advection and cross-flow according to the flow direction of materials and steam. Among the four processes, the energy consumption is the lowest, and the operation is stable. The process that is beneficial to the solid-liquid ratio and mother liquor concentration control in the evaporation tank is the advection feeding, split-effect preheating, downstream transfer of mother liquor, and split-effe...

AI Technical Summary

Problems solved by technology

Although the above-mentioned process consumes only 0.72 tons of steam per ton of salt evaporation, which is the least energy-consuming of all vacuum evaporation processes, its energy consumption is still considerable due to the nature of its evaporation

It can be found from the description of the above-mentioned material trend that the process is quite complicated and there are many kinds of equipment, which makes the investment in fixed assets of the vacuum evaporation section very high.

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