Slag-sodium alkali dual-alkali wet type flue gas desulfurization process

Abstract

The invention discloses a novel wet flue gas desulfurization process in which a slag is used as a regenerating agent while a calcined soda, caustic soda or spent caustic is used as an absorbing agent. The novel wet flue gas desulfurization process is mainly used for sulfur dioxide desulfurization for an electric plant, an industrial coal-fired boiler and other flue gas containing sulfur dioxide. The novel wet flue gas desulfurization process is characterized in that the slag from a steel plant is directly used as a desulfurization regenerating agent without being broken, namely the energy consumption is zero; no scaling and blocking problem exists in the whole running process; the desulfurization efficiency is high; an effect of processing flue gas by using a limestone/gypsum method can be achieved; the water used for desulfurization is reused in a sealing manner in the whole running process; the dosage of fresh water is greatly reduced; and the 'zero emission' of desulfurization waste water is realized. The novel wet flue gas desulfurization process has the advantages that investment of the adopted process is small, running and management costs are low, once investment of the novel wet flue gas desulfurization process is less than the investment of the limestone/gypsum method, and the total annual cost of running management is low. The regenerating agent, slag, is low in cost and is easily acquired, a desulfurization device is flexibly arranged and an occupied area is small, so that the novel wet flue gas desulfurization process has excellent cost performance and wide market prospect.

Description

technical field [0001] The invention relates to the flue gas desulfurization (Flue Gas Desulfurizaiton, FGD) of thermal power plants, industrial boilers and other sulfur dioxide-containing flue gases, and also relates to a solid waste recycling method. Background technique [0002] In recent years, my country's SO 2 The annual emissions are around 20 million tons, ranking first in the world. SO 2 The discharge of the pollution has caused acid rain in nearly one-third of my country's land area, becoming one of the three major acid rain areas in the world, and the loss caused to my country is more than 10 billion yuan every year. The focus comes from industries such as coal-fired boilers, smelting, and sintering. [0003] Currently, flue gas desulfurization (abbreviated as FGD) is the only large-scale commercial application of desulfurization technology in the world. The flue gas emitted by thermal power plants has two characteristics: one is the SO in the flue gas 2 The ...

AI Technical Summary

Problems solved by technology

[0006] The invention provides a steel slag-sodium-alkali double-alkali flue gas desulfurization process, which can solve the problem of slow dissolution of alkaline substances in steel slag and affect the desulfurization rate, achieve high desulfurization rate, and realize waste treatment with waste

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