详情描述

One, flue gas from the boiler is purified and then enters the absorption tower. Inside the tower, the flue gas flows upwards while being washed by downward flowing circulating slurry in a countercurrent manner. The circulating slurry is sprayed into the absorption tower through nozzles set within the spray layer, to remove SO2, SO3, HCL, and HF. Simultaneously, under the "forced oxidation process," the by-products of the reaction are oxidized into stone ash by the air introduced, consuming limestone as the absorbent. The circulating slurry is then pumped upwards to the spray layer by the slurry circulation pump, where it is atomized through nozzles for maximum gas-liquid contact. Each pump is typically connected to its respective spray layer, usually in a unitized system.

In the absorption tower, limestone reacts to form slurry. This slurry is then pumped out and enters the lime slurry dewatering system.

Mainly includes stone blue hydraulic cyclones (as primary dewatering equipment), slurry distributors, and vacuum belt dewatering machines. The purified flue gas passes through two-stage mist eliminators for de-misting, where the slurry mist carried by the clean flue gas is removed. Simultaneously, the mist eliminators are periodically flushed with process water according to a specific program. There are two purposes for flushing the mist eliminators: one is to prevent clogging, and the other is that the flushing water also serves as makeup water, stabilizing the level of the absorption tower.

2. Desulfurization Reaction Chemical Equation

S02 + H20 → H2S03 — Absorption

CaCO3 + H2SO3 → CaSO3 + CO2 + H2O --- Neutralization

3. CaS03+1/202-CaS04------------------ Oxide

4. CaS03 + 1/2H20 → CaS03·1/2H20 —— Crystallization

5. CaSO4 + 2H2O → CaSO4·2H2O ------------ Crystallization

6. CaSO3 + H2SO3 → Ca(HSO3)2 --- pH Control

Simultaneously, the reaction of HCL, HF, and CaCO3 in the smoke generates CaCl2 or CaF2. The pH in the absorption tower is adjusted and controlled by injecting limestone slurry.