Desulfuration process for sintering flue gas

Abstract

The invention discloses a desulfuration process for sintering flue gas, which adopts a desulfuration agent preparation system, a desulfuration system and a reclamation treatment system. The desulfuration agent is sodium bicarbonate, the 0.045mm standard sieve passing rate of which is no less than 75 percent. Compared with the prior art, the desulfuration process has the advantages that: the processing cost is over 30 percent lower than the cost of slaked lime; the prepared solid desulfuration agent is not easy to deteriorate, and has longer storage life compared with calcium hydroxide; the desulfuration efficiency is improved, and the running cost is reduced; the operation process is simplified; the desulfurized byproducts can be conveniently processed and utilized; and the produced mixture of calcium sulfate, calcium sulfite and calcium carbonate can be conveniently used for producing environment-friendly building materials such as lightweight building blocks, is far more stable than the current desulfurized byproducts and is easier to utilize so as to furthest reduce the discharge of solid wastes and the subsequent treatment expense and meet the current environment-friendly policy.

Description

technical field [0001] The invention belongs to the desulfurization process of sintering flue gas, in particular to the desulfurization process of semi-dry circulating fluidized bed sintering flue gas. Background technique [0002] The main properties and components of sintering flue gas in iron and steel plants are SO 2 600-4800mg / m 3 , a small amount of sulfur trioxide, dust content 100-450mg / m 3 , moisture content 7%-15%, temperature 85°C-190°C, smoke volume greater than 20×10 4 m 3 / hour. Even at the same emission point, SO in flue gas 2 The content may also fluctuate greatly in different time periods. Circulating fluidized bed semi-dry process is a relatively advanced desulfurization process. It is an imported project from VAI. It is mainly composed of desulfurization agent preparation system, desulfurization system and dust collection system. Slaked lime powder with high specific surface is used as desulfurization agent. In the process of lime digestion, in orde...

AI Technical Summary

Problems solved by technology

During operation, the reaction rate of the desulfurizer is low, only about 50%; and the chemical composition of by-products after desulfurization is complex: the typical composition is calcium sulfite 20-31%, calcium sulfate 8-15%, calcium hydroxide 15- 30%, recycling is difficult, such as landfilling industrial waste, the cost is very high, it not only occupies land, but also pollutes the environment twice