Method for recycling desulfurization byproduct of power plant

Abstract

The invention provides a method for recycling a desulfurization byproduct of a power plant. The method comprises the following steps: adding water into a reaction kettle to emulsify calcium sulfite, adding sodium carbonate after the emulsifying, performing heating and stirring, and performing filtering; adding sulfur powder into the obtained filtrate, heating and stirring, filtering again, and recycling filter residues in the heating and stirring process; and enabling the obtained filtrate to enter a crystallization kettle, performing reduced-pressure evaporation crystallization, filtering, returning the obtained filtrate to the crystallization kettle, and drying filter residues to obtain sodium thiosulfate. The method can recover the desulfurization byproduct calcium sulfite of the powerplant, thereby enhancing the desulfurization efficiency; the process is simple, the types of required chemicals are few, only sodium carbonate and the sulfur powder are required, and the types of required equipment are few; the product sodium thiosulfate is large in application range; and the purity requirement of calcium sulfite is low, and the final product sodium thiosulfate generated by low-purity calcium sulfite can be directly added with potassium ferrocyanide and the like as an environment-friendly gold extracting agent.

Description

technical field [0001] The invention relates to the field of desulfurization by-products in power plants, in particular to a method for recovering and reusing the desulfurization by-products in power plants. Background technique [0002] Thermal Power Plant SO 2 The main emission reduction measures are to change fuels, reduce fuel sulfur content, shut down small units and install flue gas desulfurization and other measures. When the potential of measures such as changing fuels and reducing the sulfur content of coal combustion in our country is very small, if we want to further reduce SO 2 Displacement, the key is to set the flue gas desulfurization device port. So far, my country has not fully mastered the core technology of flue gas desulfurization design and equipment supply capacity. There are continuous problems in actual desulfurization operation, and the problem of fouling and blockage is the first to bear the brunt. In the process of flue gas desulfurization, the ...

AI Technical Summary

Problems solved by technology

Calcium sulfite is unstable, not only may itself pollute the water body, but may re-release SO after decomposition 2 into the flue gas, thereby reducing the desulfurization efficiency

At present, most power plants treat calcium sulfite by oxidizing it, but the oxidation of calcium sulfite, whether it is homogeneous or heterogeneous, depends on the specific experimental parameters, such as liquid phase composition (concentration of sulfite, dissolved oxygen, pH value), temperature, trace catalyst (inhibitor), etc., can all have a very significant impact on the reaction rate, so the data reproducibility of this type of experiment is not very ideal

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