System and process for preparing low-salt dense soda ash by liquid-phase hydration

Abstract

The invention discloses a system and a process for preparing low-salt dense soda ash by liquid-phase hydration. The method comprises the following steps of: adding light soda ash with the temperature of more than 93 DEG C, condensate water and saturated solution of sodium carbonate according to a mass ratio of 1:0.22:1.4-1:0.22:2.0 into a hydration tank for hydration, wherein the reaction temperature is controlled to be between 100 and 104 DEG C and the reaction time is 20 to 25 minutes, and crystallizing the soda ash in a form of a monohydrate soda, namely Na2CO3.H2O after the reaction; after separating the monohydrate soda crystal slurry with a hydrocyclone separator, feeding the top liquid into a mother liquor storing barrel and feeding the bottom liquid into a centrifuge; after dehydrating the bottom liquid with the centrifuge to obtain a monohydrate soda filter cake; and drying, cooling and screening the monohydrate soda filter cake to obtain the finished product, namely the low-salt dense soda ash, wherein when the centrifuge is used for dehydrating, water is added to wash off a part of salts. The system can guarantee the constant material level of a material bin so that the feeding of the soda ash is stable. The obtained soda ash product has the advantages of large crystallization granule size, high first-rate product rate and high added value, wherein the product with crystallization granule size of more than 180 mu m is up to over 75 percent; the qualification rate is up to 100 percent; and the first-rate product rate is up to 95 percent.

Description

technical field [0001] The present invention relates to a system and production process for producing low-salt heavy soda ash, in particular to a system and a production process for producing low-salt heavy soda ash by using liquid-phase hydration method using light soda ash prepared by sesquialkali process or carbonization process as raw material systems and production processes. Background technique [0002] At present, heavy soda ash has replaced light soda ash as industrial raw material in many places, and heavy soda ash has many advantages over light soda ash. Nowadays, the production of heavy soda ash mostly adopts the solid phase hydration method. The solid phase hydration method produces heavy soda ash. Due to the limitation of its process, the particle size of the alkali is uneven, and the cost is relatively high. In addition, the salinity of the alkali is not easy to control. At present, the production of heavy soda ash by liquid phase hydration method can obtain...

AI Technical Summary

Problems solved by technology

The production of heavy soda ash by solid phase hydration, due to the limitation of its process, makes the particle size of the alkali uneven, and the cost is relatively high. In addition, the salinity of the alkali is not easy to control

At present, the production of heavy soda ash by liquid phase hydration can produce low-salt heavy soda ash with a qualified rate of 100%. However, due to system defects, it is easy to produce fine crystals, resulting in a high-quality product rate of about 88%.

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