Low-concentration flue gas desulfurization method for hydroelectric silicon smelting

Abstract

The invention discloses a low-concentration flue gas desulfurization method for hydroelectric silicon smelting. The method comprises the following steps: 1) preparing absorption slurry, namely fully uniformly mixing a desulfurization adsorbent ground to the granularity of 325-400 meshes and water so as to obtain the absorption slurry; 2) absorbing acid gas, namely enabling the absorption slurry and flue gas to be fully contacted in a desulfurizing tower when flue gas during hydroelectric silicon smelting enters a desulfurization system, so that acid gas and particles in the flue gas are absorbed by the absorption slurry; and 3) discharging the flue gas, namely detecting the emission concentration of SO2 at the outlet, discharging the SO2 while meeting requirements, if not, returning to thedesulfurization system to treat, filtering the absorption slurry after absorption, and returning the filtrate to the step (2) to serve as absorption liquid, and taking the filter residues as by-products for sales, thereby obtaining the product. According to the method disclosed by the invention, limestone and other desulfurization adsorbents are mixed with water to prepare the absorption slurry,the flue gas enters the desulfurization system to be fully contacted with the slurry, and the acid gas and particles are removed, so that the emission concentration of sulfur dioxide in the flue gas is reduced to 80mg / Nm3, and green and environmental-friendly production is effectively realized.

Description

technical field [0001] The invention belongs to the technical field of flue gas desulfurization treatment, and in particular relates to a low-concentration flue gas desulfurization method for hydropower silicon smelting. Background technique [0002] Industrial silicon production is a production process in which silicon ore is used as raw material and carbon material is used as reducing agent to smelt in an electric furnace container. The essence of the reaction is to smelt and purify silicon by redox reaction between reducing carbon and silicon dioxide. Relying on abundant silicon mineral resources and hydropower energy, Yunnan Province has obvious advantages and conditions to promote the development of hydropower silicon industry. At the same time, it also puts forward new requirements for green and environmental protection production. The most important thing is the low-concentration flue gas treatment of hydropower silicon smelting . [0003] The discharge of electric f...

AI Technical Summary

Problems solved by technology

The high content of silica in the flue gas is very harmful to the desulfurization system. The silica entering the absorption slurry will hinder the chemical reaction in the system to a certain extent, resulting in the desulfurization efficiency and poor gypsum quality.

Moreover, the particle size of silicon dust in the flue gas is mostly less than 1 μm. If things go on like this, it will also cause a relatively large health hazard to the corresponding staff.

[0004] Limestone wet desulfurization methods have been used in the prior art, but most of them are aimed at traditional zinc, copper and other smelting processes, and most of them are thermal power smelting, the exhaust gas volume and sulfur content are extremely high, and the silicon dioxide content is almost negligible

Although there are existing literatures on flue gas treatment of silicon smelting, most of them are directly following the flue gas treatment parameters of other metal smelting processes