Device and method for mixed smoke evaporation to dryness of desulfuration wastewater

Abstract

The invention relates to a device and method for mixed smoke evaporation to dryness of desulfuration wastewater. The wall attaching phenomenon or the flue blocking phenomenon exists in an existing mode of boiler smoke evaporation to dryness of desulfuration wastewater, and the desulfuration efficiency is low. The device comprises a mixed gas evaporation to dryness desulfuration part and a gas tempering desulfuration part. The mixed gas evaporation to dryness desulfuration part comprises a drying tower, a wastewater preprocessing pipeline and a mixed gas pipeline. The drying tower is communicated with a flue main pipe through a tail gas pipe. The mixed gas pipeline comprises a main pipe, a first branch pipe and a second branch pipe which is communicated with external air and flows through an air preheater. Smoke and heated external air are mixed and sent into the drying tower so that evaporation to dryness can be conducted on desulfuration wastewater. The wall attaching phenomenon during mixed smoke evaporation to dryness of desulfuration wastewater is effectively solved, the service life of the drying tower is ensured,the influences of external air to boiler efficiency can be effectively reduced,the desulfuration efficiency is effectively improved, the desulfuration wastewater volume can be decreased, the workloads of evaporation work are relieved, and the heat loss for evaporation of desulfuration wastewater is reduced.

Description

technical field [0001] The invention relates to the field of steam turbine power generation, in particular to a device and method for evaporating and drying desulfurization wastewater by boiler flue gas. Background technique [0002] After coal is burned in the boiler, sulfur-containing gaseous pollutants will be formed. These substances will enter the exhaust pipe along with the boiler exhaust gas, and then pass through the economizer, SCR (Selective Catalytic Reactor), AH (Air Preheater), ESP (Electric precipitator) after being absorbed by FGD (desulfurization absorption tower), the concentrated solution (containing various salts) of the desulfurization absorption tower is discharged in the form of desulfurization wastewater, which is likely to cause secondary pollution. In order to eliminate the discharge of desulfurization wastewater, In the prior art, L-shaped desulfurization wastewater flue gas evaporators or flue gas bypass treatment devices are often used for treatme...

AI Technical Summary

Problems solved by technology

The outside air needs to be preheated before mixing with high-temperature flue gas, which not only ensures that the mixed gas has enough heat for evaporating desulfurization wastewater, but also avoids partial desulfurization wastewater in the drying tower not being able to evaporate in time due to uneven mixing of hot and cold air. dry problem, thus avoiding the mixing of desulfurization wastewater and ash and sticking to the wall

Images