Method for extracting ammonium sulfate from ammonia desulphurization wastewater by oxidation process

The invention provides a method for extracting ammonium sulfate from ammonia desulphurization wastewater by an oxidation process, and belongs to the technical field of treatment of desulphurization waste solutions. The method comprises the steps of: carrying out oxidation reaction in a manner of blowing air or oxygen into the ammonia desulphurization wastewater, wherein in the oxidization reaction, ammonium thiosulfate in the desulphurization wastewater is oxidized into ammonium sulfate, ammonium thiocyanate is not oxidized and further maintained in the desulphurization wastewater; and then extracting ammonium sulfate in an evaporation or crystallization manner. The method disclosed by the invention is suitable for treatment of the desulphurization wastewater produced in the air desulfurization and cyanide-removal processes by a catalytic oxidation method. The method is suitable for treatment of waste liquor in the field of the desulfurization process of hydrogen sulfide containing gases such as coke even gas, natural gas, coal bed gas and refinery gas. By using the method disclosed by the invention, ammonium thiosulfate salt in the wastewater can be transformed into ammonia sulfate salt, ammonium thiocyanate is protected, and the ammonium thiosulfate salt and the ammonium thiocyanate can be separated from the wastewater and purified to obtain the products.