To produce the passing sodium carbonate of granulation condition with the product null (i) porous membrane atomization corning which can obtain too much

摘要

This invention too much the granule condition which possesses low TAM- value was covered regards the manufacturing method of sodium carbonate. It does at temperature T inside the range of 35 - the 100C _U in the porous membrane coating, with the spraying of the aqueous solution which at least contains one coating component it produces, inside the range of 45 - the 75C with porous membrane spraying granulation. According to this invention, a) after the porous membrane spraying granulation, but before the coating, it executes rear drying with T _{NT which} is higher than T _{G, or} b) at least with two processes, T _G1 and T _G2,... executes porous membrane spraying granulation with T _Gn, when at that time, T _G2 or T _Gn are higher than T _G1, form 2/3 of the granules with T _G1 rear drying is unnecessary; Or drying c) rear is not after the granulation and after the covering for the first time, furthermore it does with T _UNT, at that time, T _{UNT the} 20C is higher than T _G at least.