Basic aluminum sulfate regeneration desulfurization process based on retarded oxidation and multi-field synergistic desorption

Abstract

The invention relates to the technical field of energy and power and chemical industry production, and particularly discloses a basic aluminum sulfate regeneration desulfurization process based on retarded oxidation and multi-field synergistic desorption. The process includes: performing desulfurization treatment on dust-bearing raw flue gas through combination of SO3<2-> retarded oxidation and multi-field synergistic desorption, thereby obtaining fly ash and dust-removed raw flue gas; immersing the fly ash in desulfurization rich liquor to prepare aluminum sulfate, and mixing the aluminum sulfate with water, CaCO3 or CaO to obtain basic aluminum sulfate; mixing the basic aluminum sulfate, a oxygen blocking agent, desulfurization rich liquor and desorption lean liquor to obtain a desulfurization mixed liquid; and performance a reaction on the dust-removed raw flue gas and the desulfurization mixed liquid to obtain desulfurization rich liquor and clean flue gas. In the invention, by combination of the characteristics of the desulfurization agent and aiming at the common defects of regeneration desulfurization process, the basic aluminum sulfate having excellent comprehensive performance is selected, so that the desorption effect of the basic aluminum sulfate regeneration desulfurization process is enhanced and the cost of the basic aluminum sulfate desulfurization agent, and meanwhile the technical purpose of economic operation is achieved.

Description

technical field [0001] The invention relates to the technical fields of energy, power and chemical production, and specifically relates to a basic aluminum sulfate regenerative desulfurization method based on oxidation inhibition and multi-field synergistic desorption. Background technique [0002] SO at home and abroad 2 Recyclable wet regenerative flue gas desulfurization technologies mainly include sodium sulfite circulation method, sodium citrate method, organic amine method and basic aluminum sulfate regeneration method, among which the traditional thermal desorption basic aluminum sulfate regenerative desulfurization method uses industrial aluminum sulfate [Al 2 (SO 4 ) 3 】with CaCO 3 Or CaO reacts in aqueous solution to prepare basic aluminum sulfate [(1-x)Al 2 (SO4) 3 ·xAl 2 o 3 】Desulfurization solution for SO 2 Absorption, desulfurization rich liquid thermal desorption to obtain high-purity SO 2 At the same time, basic aluminum sulfate can be regenerated a...

AI Technical Summary

Problems solved by technology

[0003] However, there are certain defects in the basic aluminum sulfate regeneration method of the prior art, which are shown in the following points: traditional thermal desorption of SO 2 The desorption rate is low and the desorption time is long, which leads to the rapid attenuation of cycle desulfurization-desorption performance and increases the supplementary cost of basic aluminum sulfate; the simultaneous presence of SO 2 3- Oxidation problem, which weakens the desorption regeneration performance and indirectly increases the supplementary cost of basic aluminum sulfate. These problems are the technical bottlenecks that restrict the sustainable development and economic operation of this method

[0004] In summary, the traditional basic aluminum sulfate regeneration method is due to the presence of SO in the desulfurization-desorption cycle 3 2- Oxidation leads to a decrease in desorption potential, and at the same time, traditional thermal desorption or auxiliary steam stripping cannot achieve the ideal desorption performance, resulting in the limitation of desulfurizer regeneration. The combined results lead to an increase in desulfurizer supplementary costs, which is not conducive to industrial application and promotion.

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