Method for comprehensively recovering lead, zinc and iron in gas ash of blast furnace

Abstract

The invention discloses a method for comprehensively recovering lead, zinc and iron in gas ash of a blast furnace. Anthracites of 20-30% of the total mass of blast furnace gas mud are fed in the blastfurnace gas mud containing lead, zinc and iron, and roasting accelerants of 4.0-6.0% of the total mass of the blast furnace gas mud and compounded by Na2CO3 and CaCO3 are fed; the materials are uniformly mixed and fed in a rotary kiln or a rotary hearth furnace, with a smoke recovery system, for reduction roasting; gas is extracted to feed in the smoke recovery system for treatment; mud settlingproducts containing lead and zinc are collected; roasting ores discharged from the rotary kiln or the rotary hearth furnace are quenched by water; and the water-quenched materials are fed in an ore grinding-weak magnetic separation recovery system to obtain iron concentrate powder. The method can synchronously realize the zinc volatilization rate of above 95% and the lead volatilization rate of above 86%, obtains iron concentrates with the grade of above 65.00%, not only can effectively recover lead, zinc and iron resources in the gas ash, but also can reduce the energy consumption, and improves the productivity.

Description

technical field [0001] The invention relates to a method for comprehensive utilization of iron and steel smelting solid waste, in particular to a method for recovering lead, zinc and iron in blast furnace gas ash through roasting volatilization-magnetic separation. Background technique [0002] Blast furnace gas ash is a metallurgical waste produced during the blast furnace smelting process. In recent years, due to the sharp increase in my country's steel production, the amount of gas ash produced has also increased. According to statistics, the amount of blast furnace gas ash in my country is about 10-25kg / t iron, and the annual pig iron output in my country exceeds 700 million tons, so more than 10 million tons of blast furnace gas ash will be produced in my country every year. These plasters contain a large amount of valuable elements such as iron, zinc, lead, chromium, nickel, etc., and have high utilization value. Therefore, major iron and steel enterprises and related ...

AI Technical Summary

Problems solved by technology

But see from existing report, the accelerator effect that uses at present is not satisfactory, mainly shows in: 1. can not promote the high-efficiency volatilization of lead, zinc simultaneously (the promotion effect to lead volatilization is obvious, the promotion effect to zinc volatilization is weaker, even hinder operation); 2. the effect of promoting the volatilization of lead and zinc is not good (the volatilization rate is generally about 80%) under the relatively low temperature; Negative impact; ④A large amount of accelerator is used (about 15%)

Images