1. Copper powder is roasted at 600 ~ 700℃ by sulfuric acid method, oxidized into copper oxide, decomposed and clarified by sulfuric acid to remove insoluble impurities, cooled, crystallized, filtered and dried to obtain the finished product of copper sulfate. The reaction formula is as follows. 2. The waste electrolyte (containing Cu50 ~ 60g/L, H2SO4 180 ~ 200g/L) from the electrolyte recovery method reacts with the fine copper powder made from the calcined copper mud. After the reaction liquid is separated and settled, the clear liquid is cooled, crystallized, separated and dried to obtain the finished product of copper sulfate. 3. The copper compound precipitate in the cuprammonium acetate solution in the copper washing tower when the synthetic ammonia feed gas from the nitrogenous fertilizer plant is recycled to Chemicalbook. After roasting at 700℃, it is oxidized to copper oxide and then reacts with sulfuric acid to produce copper sulfate. 4. Chemical concentration crystallization method adopts low-grade copper oxide ore, which is crushed to a certain particle size, dipped in sulfuric acid, and added with copper dissolving and iron precipitating agent to obtain copper sulfate solution with the ratio of copper to iron greater than 100. Then, chemical concentration agent is added for concentration, and 70% ~ 90% of water is drained away. Finally, after evaporation, cooling crystallization, separation and air drying, the finished copper sulfate product is prepared.