Recovery method for SCR waste flue gas denitration catalyst

Abstract

The invention relates to a recovery method for an SCR waste flue gas denitration catalyst, and adopts a hydrometallurgy process. After the SCR waste flue gas denitration catalyst is smashed and subjected to pre-calcination treatment, a NaOH solution is added according to a ratio for dissolution. After the catalyst is dissolved, solid-liquid separation is performed, sulfuric acid is added into the obtained precipitation, and the precipitation is steeped, precipitated, hydrolyzed, subjected to salt treatment, and calcinated to obtain TiO2. Sulfuric acid is added into the solution obtained from the first solid-liquid separation to adjust the pH value, excess ammonium nitrate is added to precipitate vanadium, and second solid-liquid separation is performed. Ammonium metavanadate obtained from filtration is subjected to pre-calcination to obtain a V2O5 finished product. Hydrochloric acid is added into the solution obtained from the second solid-liquid separation to adjust the pH value, and NaCl is added to obtain sodium tungstate. The sodium tungstate is subjected to purification, filtration, ion exchange, and other processes to separate impurities, and subjected to evaporative crystallization to obtain a sodium tungstate finished product. The method provided by the invention is simple in technology, general in equipment, easily available in raw material, low in cost and high in recovery rate.

Description

technical field

[0001] The invention relates to a method for recovering SCR waste flue gas denitrification catalyst, which adopts the process of hydrometallurgy and belongs to the field of non-ferrous metal recovery. Background technique

[0002] Since the reform and opening up, my country's power industry has developed vigorously. In 2005, my country's installed power generation capacity has exceeded 450 million kW. According to statistics, more than 90% of NO in my country's air pollutants x Originated from the combustion process of fossil fuels (such as coal, oil, natural gas, etc.), 70% of which comes from the combustion of coal, and the coal used for power generation in thermal power plants accounts for 70% of the country's coal combustion. By 2005, the national NO x The total emissions have reached about 18 million tons, and the emissions from the power industry account for about 1 / 2. According to the current emission control level, in 2020 China's NO x Emissions ...

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