Process method for preparing sodium hypochlorite from waste sulfuric acid residual chlorine

The invention relates to a process method for preparing sodium hypochlorite from waste sulfuric acid residual chlorine. The method comprises the steps: collecting residual chlorine in a waste sulfuricacid solution and residual chlorine in production; controlling the mass fraction of a circulating alkali liquor sodium hydroxide solution in an alkali liquor elevated tank alkali supply system and analkali liquor spraying circulating system to be 15%; controlling the temperature and flow quantity of a cooling water inlet of the alkali liquor heat exchange system and the temperature and flow quantity of an alkali liquor inlet and an alkali liquor outlet of the alkali liquor heat exchange system; controlling a fan circulating system to ensure the micro negative pressure of the system; collecting chlorine overflowing from a tank I into a tank II area and a tank III area; pumping the chlorine into a preparation device together with a sodium hydroxide solution from an alkali liquor elevated tank, and reversely sprayin