Flue-gas desulphurization system and flue-gas desulphurization method

Abstract

The invention relates to a flue-gas desulphurization system and a flue-gas desulphurization method. The flue-gas desulphurization system comprises a desulphurization absorbing tower connected with a limestone slurry feeding pipe, a flue-gas pipeline, a cloth-bag dust remover, a two-stage mist remover, a blower, a slurry discharging pump I and a hydraulic cyclone connected with the slurry discharging pump I, and is characterized in that the hydraulic cyclone is also connected with a slurry discharging pump II and a filtering machine; and the slurry discharging pump II is also connected with a dewatering screen which is also respectively connected with the filtering machine and a gypsum stockpile. The flue-gas desulphurization method comprises the following steps that: flue gas is dissolved in limestone slurry and then oxidized and crystallized to form gypsum slurry; and the gypsum slurry is concentrated by the hydraulic cyclone, the underflow of the hydraulic cyclone is pumped into the dewatering screen for dewatering by the slurry discharging pump II, and the overflow of the hydraulic cyclone is fed into the filtering machine for filtering. According to the flue-gas desulphurization system and the flue-gas desulphurization method, since the filtering machine and the dewatering screen are additionally arranged behind the hydraulic cyclone of the flue-gas desulphurization system and the dewatering screen is adopted for dewatering, so that the problem of difficult dewatering of the gypsum is effectively solved and the additional value of a gypsum product is high.

Description

technical field [0001] The invention belongs to the technical field of flue gas purification, and in particular relates to a flue gas desulfurization system and a flue gas desulfurization method. Background technique [0002] In order to prevent air pollution caused by flue gas sulfur exhaust, flue gas desulfurization is required. At present, wet desulfurization and dry desulfurization processes are often used. Its wet desulfurization process: limestone powder enters the slurry tank through the feeder at the bottom of the limestone silo, and is made into limestone slurry, which is then pumped to the desulfurization absorption tower through the limestone slurry pump. The slurry circulates up and down in the absorption tower. The flue gas enters the absorption tower after being dedusted by the bag filter. The flue gas in the absorption tower is in reverse absorption contact with the slurry. Calcium sulfite, which crystallizes to form gypsum. After desulfurization in the upp...

AI Technical Summary

Problems solved by technology

Because gypsum is relatively sticky, it is not easy to dehydrate with a vacuum tape dehydrator, and it is not easy to produce by-products that meet the dehydration requirements, and it is easy to form secondary pollution

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