Sodium dichromate closed circulation clean production method for preparing sodium chlorate

The invention discloses a sodium dichromate closed circulation clean production method for preparing sodium chlorate. A sodium dichromate closed circulation clean production technique in a sodium chlorate production process is proposed in the method, and the clean sodium chlorate production without chromium slag emission is realized by using the method. A ceramic membrane filtering technology is adopted, and a clean production process comprising the steps of salt dissolving, double-alkaline pretreatment, ceramic membrane, barium chloride process pretreatment, barium sulfate recovery, ceramic membrane, electrolysis, crystallization and electrolysis is proposed, so that the concentration of NaCl entering saline water in an electrolytic tank is larger than or equal to 300g/L, the contents of Ca , Mg , SO4 and Ba meet an electrolysis requirement, the content of SO4 in a crystallized mother solution is lower than 1mg/L, the electrolysis can be directly carried out without treating the mother solution, so that chromium slag is prevented from being generated. The sodium dichromate closed circulation clean production method in a sodium chlorate production process, disclosed by the invention, has the advantages of discharging no chromic salt mud, saving the precious chromium resource, solving the discharging problem of hexavalent chromium generated by sodium chlorate plants and generating a certain economic benefit.