High-temperature flue gas washing, concentrating and desalting device and desalting method

Abstract

The invention relates to the technical field of flue gas treatment, in particular to a high-temperature flue gas washing, concentrating and desalting device and method. The device comprises a neutralization pipeline used for conveying high-temperature flue gas containing hydrogen chloride, wherein a neutralizer adding pipe is arranged on the neutralization pipeline; a venturi tube which is provided with a jet outlet; a flue gas dehydration crystallization tower, wherein a smoke exhaust pipe is arranged at the top of the flue gas dehydration crystallization tower, the lower end of the flue gas exhaust pipe penetrates through and extends into the flue gas dehydration crystallization tower, a tangential inlet is formed in the side wall of the upper part of the flue gas dehydration crystallization tower, and an injection outlet of the Venturi tube is connected with the tangential inlet; a crystal recovery device which is connected with the bottom of the flue gas dehydration crystallization tower; the method comprises the steps of flue gas and neutralizer mixing, heat exchange jet evaporation, crystallization sedimentation and crystal recovery. The flue gas waste heat is utilized, the energy consumption is low, calcium chloride crystals can be obtained through evaporative crystallization, flue gas can be effectively dechlorinated, and the membrane concentrated solution generated by sewage treatment can be cooperatively treated.

Description

technical field [0001] The invention relates to the technical field of flue gas treatment, in particular to a high-temperature flue gas washing, concentration and desalination device and a desalination method. Background technique [0002] Solid waste (such as sludge, garbage) contains more chloride ions, which will become hydrogen chloride gas and enter the flue gas during incineration. If wet flue gas treatment is used, these chloride ions will enter the flue gas washing water to form High-salt wastewater is difficult to biochemically treat. In addition, the membrane concentrate produced by sewage treatment contains high concentrations of salt and refractory pollutants. At present, MVR evaporation and concentration is mainly used for treatment, which consumes a lot of energy and is prone to fouling, which reduces the treatment efficiency. Contents of the invention [0003] In order to solve the above-mentioned technical problems, the present invention provides a flue ga...

AI Technical Summary

Problems solved by technology

[0002] Solid waste (such as sludge, garbage) contains more chloride ions, which will become hydrogen chloride gas and enter the flue gas during incineration. If wet flue gas treatment is used, these chloride ions will enter the flue gas washing water to form High-salt wastewater, difficult to carry out biochemical treatment

In addition, the membrane concentrate produced by sewage treatment contains high concentration of salt and refractory pollutants. At present, MVR evaporation and concentration is mainly used for treatment, which consumes a lot of energy and is prone to fouling, which reduces the treatment efficiency.

Images