Production process of sodium bicarbonate

The invention discloses a production process of sodium bicarbonate. The process comprises the following steps: i) preparing a caustic soda preparation solution from caustic soda liquid and process water; (ii) introducing liquid carbon dioxide into a vaporizer for vaporization; (iii) introducing the caustic soda preparation liquid and vaporized carbon dioxide into a carbonization tower for carbonization synthesis to obtain carbonized liquid; and iv) transferring the carbonized liquid into a crystallizer for crystallization, centrifuging and washing the crystallized liquid to obtain a wet material, and drying the wet material to obtain the final product. Liquid caustic soda is adopted as a raw material, a two-step carbonization method is adopted for preparation, the raw material is in a food additive grade, the yield of mother liquor is small, the product impurity content is low, the number of application times is increased, the wastewater discharge amount is reduced, meanwhile, the product yield is high, the p