The invention relates to the field of
chemical production, in particular to a
system and a preparation method for producing low-salt soda ash by a combined soda production process, a
carbonization tower is arranged at the front end of the
system, filtering and washing equipment and calcining equipment are sequentially arranged behind the
carbonization tower, and the filtering and washing equipment comprises primary washing equipment and secondary washing equipment; the method comprises the following steps: treating a carbonizer extraction liquid through primary washing equipment to obtain
sodium bicarbonate, and enabling the generated
mother liquor to enter a
mother liquor circulating
system; the
sodium bicarbonate is subjected to back washing and
dehydration treatment, and generated
mother liquor enters a mother liquor circulating system; calcining the re-washed
sodium bicarbonate to obtain a
sodium carbonate product; the total washing water amount used in the method is 0.58-0.62 m < 3 > /
ton of
sodium carbonate, under the condition that a small amount of washing water is used, the stability of the mother liquor is maintained, meanwhile, the
salt content of the prepared
sodium carbonate is 0.2-0.3 wt%, the purity can reach 99.4%, the quality requirement of low-
salt sodium carbonate is met, and the method is suitable for industrial production. The prepared soda ash can be applied to multiple fields of
optical glass manufacturing,
kinescope glass
bulb manufacturing, vehicle-mounted
glass manufacturing and the like.