Energy-saving and anti-scaling dual-alkali desulfuration method

Abstract

The invention discloses an energy-saving and anti-scaling dual-alkali desulfuration method. Hot flue gas is fed into an air heat exchange system to exchange heat with cold air; the heated cold air is fed into a coal combustion furnace to be used as an oxidizing agent; the flue gas subjected to heat exchange is fed into a dust collector to be subjected to dust removal so as to obtain the purified flue gas; the purified flue gas is led into a desulfurizing tower; a soda absorbent is adopted to carry out counter-current contact absorption; the absorbent which adsorbs sulfur dioxide flows into a circulating pool outside the desulfurizing tower to carry out circulating absorption so as to reduce scaling of absorption liquid in the desulfurizing tower; after the pH value of the absorbent in the circulating pool reaches the requirement, the absorbent is fed into a regeneration pool; quick lime is added to carry out regeneration of the absorption liquid; and supernatant liquid is fed into a sodium-type cation exchanger to be subjected to exchange so as to remove residual calcium ions in the supernatant liquid, thereby preventing scaling in the desulfurizing tower and a pipeline. The method not only can save energy, but also has high desulfurizing efficiency; and the insides of the desulfurizing tower and the pipeline are difficult to scale.

Description

technical field [0001] The invention belongs to the field of flue gas purification, and specifically relates to an energy-saving and anti-scaling double-alkali desulfurization method, which can be applied to the fields of refractory materials, coking, ceramics, carbon and the like. Background technique [0002] With the continuous development of the economy, the destruction of the environment by human beings is becoming more and more serious. The continuous occurrence of natural disasters has continuously improved people's awareness of environmental protection, and the governance of industrial coal-fired boilers has also been continuously improved. At the same time, as my country With the increase of combustion boilers and the rapid consumption of low-sulfur coal resources, there will be more and more boilers using medium-high sulfur coal as the main fuel. At the same time, the emission indicators of sulfur dioxide will become more and more stringent in various places. Enviro...

AI Technical Summary

Problems solved by technology

This process has practical value for the establishment and stable and reliable operation of the dual-alkali desulfurization unit, with a reliability of over 98%, but there are also problems of low efficiency and easy scaling

[0025] The existing technology mainly has the following problems: 1. Low desulfurization efficiency; 2. Calcium scaling in the absorption tower and circulation pipeline; 3. Sodium sulfate crystallization in the absorption tower