Method for strengthening treatment of printing and dyeing wastewater by printing and dyeing sludge firing product and acid leaching solution thereof

The invention relates to a method for strengthening treatment of printing and dyeing wastewater by a printing and dyeing sludge firing product and acid leaching solution thereof, which comprises the following steps: taking physico chemical and biochemical mixed sludge of a printing and dyeing sewage treatment works; baking the sludge to constant weight, firing in a muffle furnace for 2 to 5 hours, taking the sludge out, cooling and passing a 100-mesh sieve to obtain sludge firing residue; adding mixed acid and water into the firing residue for reaction for 6 hours to obtain the acid leaching solution; adding the acid leaching solution in feeding water of a printing and dyeing wastewater treatment system, stirring for 2 to 6min, and precipitating for 30min; and adding the sludge firing residue in discharging water, stirring for 0.5h and standing for precipitation and separation. The method utilizes heavy metal ions rich in the sludge firing product to realize the aim of resources; after the feeding water is ad