Dual-alkali flue gas desulfurization process

Abstract

The invention discloses a flue gas desulfurization process adopting a dual-alkali method, and relates to the technical field of lime production. Lime powder is synchronously added, slurry in the oxidation regeneration tank is sent into a concentration tank after oxidation aeration, supernate in the concentration tank is sent into a clear liquid tank, precipitates in the concentration tank are sent into a filter press for dehydration, and water removed by the filter press is also conveyed into the clear liquid tank; water in the clear liquid tank is treated by a filtering device and then is pumped to the circulating water tank to realize desulfurization; water in a clear liquid pool enters the supporting box in the filtering device, is filtered by the polypropylene melt-blown filter elements in the two filtering boxes and then is discharged through the water pipe, the sludge content in the water is reduced, and after the polypropylene melt-blown filter elements in the filtering boxes are used for a period of time, the sludge on the filter elements is more, so that the filtering boxes and the partition plate rotate by 180 degrees, and the sludge in the water is discharged through the water pipe. The sludge falls into the material guide plate due to the gravity of the sludge, and meanwhile, the sludge is compacted due to the vibration of the material guide plate.

Description

technical field [0001] The invention relates to the technical field of lime production, in particular to a double-alkali flue gas desulfurization process. Background technique [0002] In the existing sodium hydroxide single-alkali desulfurization process, when the accumulation of sulfate in the system reaches a certain concentration, it will affect the desulfurization efficiency and should be removed, and the amount of sludge in the water entering the circulating pool is relatively high, which affects the process cycle. Therefore, the process needs to be optimized; [0003] At the same time, the integrated setting of the ash outlet of the lime kiln makes the heat dissipation effect poor, and the vibration motor is installed inside the device, which is inconvenient for maintenance. At the same time, due to the high temperature of the working environment, the service life is shortened, and the maintenance workload increases. Due to the low concentration of sodium sulfite in t...

AI Technical Summary

Problems solved by technology

[0002] In the existing sodium hydroxide single-alkali desulfurization process, when the accumulation of sulfate in the system reaches a certain concentration, it will affect the desulfurization efficiency and should be removed, and the amount of sludge in the water entering the circulating pool is relatively high, which affects the process cycle. Therefore, the process needs to be optimized;

[0003] At the same time, the integrated setting of the ash outlet of the lime kiln makes the heat dissipation effect poor, and the vibration motor is installed inside the device, which is inconvenient for maintenance. At the same time, due to the high temperature of the working environment, the service life is shortened, and the maintenance workload increases. Due to the low concentration of sodium sulfite in the initial operation , the regeneration rate of supplemented lime is extremely low, and it will cause the supernatant to contain calcium hydroxide solution, and calcium sulfite and calcium sulfate crystallization will occur after multiple desulfurization cycles, which will affect the normal operation of the desulfurization system in severe cases

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