Abstract: Wet type DeSOx & DeNOx process is adopted in coke oven flue gas purification，and its byproduct ammonium sulfate mother liquor is delivered to the mother liquor storage tank of the saturator unit，and finally the ammonium sulfate product is produced after the treatment of the spray saturator and equilibrating with the existing production. However，the ammonium sulfate mother liquor after DeSOx & DeNOx has a certain impact on the production of the saturator system，therefore rationally operating and stabilizing the saturator system plays an important role in the production.

Key words: DeSOx &, DeNOx, Ammonium sulfate, Saturator