Method and device for recycling W and V from waste flue gas denitration catalyst

The invention discloses a method and device for recycling W and V from a waste flue gas denitration catalyst. The method includes the steps that 1, the catalyst is crushed, concentrated sulfuric acid is added for acidolysis, water is added after acidolysis, and an oxygen titanium sulfate solution is obtained; 2, the oxygen titanium sulfate solution is filtered, filter residues are collected for standby application, the filter liquor is heated, concentrated and hydrolyzed, and a hydrolysis product is obtained; 3, the hydrolysis product is filtered, and settlement treatment is conducted on the filter liquor; 4, filtering is conducted after settlement treatment, supernatant liquid is taken, an excessive amount of NH Cl is added to the clear liquid for a reaction, then filtering is conducted, and ammonium metavanadate sediment is obtained; the ammonium metavanadate sediment is calcined, and V O is obtained; 5, an excessive amount of ammonium hydroxide with the concentration being 10%-28% is added to the filter residues in step 2 for a reaction, and then filtering is conducted; the filter liquid is heated to be 80 DEG C-100 DEG C, and an ammonium paratungstate crystal is obtained; the ammonium paratungstate crystal is dried and calcined, and the WO is obtained. By means of the method and device, the V O and the WO which are both high in purity and recovery rate can be extracted from the waste flue gas denitration catalyst.