Blast furnace gas ash resource utilization method

Abstract

The invention provides a blast furnace gas ash resource utilization method. The blast furnace gas ash resource utilization method comprises the following steps of evenly mixing blast furnace gas ash and water to obtain first slurry; conducting hydraulic cyclone separation on the first slurry to obtain zinc-rich slurry containing zinc-containing particles with the grain size D50 less than 0.025 mmand iron-carbon slurry containing iron and carbon particles with the grain size D50 greater than or equal to 0.025 mm; mixing the iron-carbon slurry with ingredients, adding water to mixing slurry toobtain second slurry and conducting flotation treatment on the second slurry to obtain a carbon-rich material and an iron-rich material. Through the blast furnace gas ash resource utilization method,blast furnace gas ash is graded in a hydraulic cyclone mode, the grain size ratio of flotation materials is optimized, and the phenomenon that particles with the grain size less than 0.025 mm cannot get rid of the influence of turbulent flow, and mismatching is caused is avoided. The zinc content of a zinc-rich product obtained finally reaches up to 6.55 wt%, the carbon content of a carbon-rich product reaches up to 60.64 wt%, and the iron content of an iron-rich product reaches up to 58.7 wt%

Description

technical field [0001] The invention belongs to the technical field of resource recovery, and relates to a method for recycling fly ash, in particular to a method for resource utilization of blast furnace gas ash. Background technique [0002] Blast furnace gas ash is the excrement produced during blast furnace ironmaking. In the process of blast furnace ironmaking, the zinc, aluminum, lead and other impurities contained in iron ore raw materials are reduced under high temperature conditions and form steam, which is discharged with blast furnace gas together with ore, coke, solvent and other dust particles, and then wet Dry dust removal system captures and removes, which is one of the main solid emissions of iron and steel enterprises. [0003] Blast furnace gas ash has both resource and environmental hazards. Blast furnace gas ash generally contains 0.5-2wt% zinc, 20-45wt% iron, 25-50wt% carbon, and the balance is other elements. If all the metal resources in it can be r...

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Problems solved by technology

If the flotation method is directly used, it is difficult to effectively separate the powder with a small particle size according to the difference in the hydrophobicity of the particle surface, and it can only follow the water flow to randomly form the foam layer or stay at the bottom of the tank, and the mismatch content will increase, which will deteriorate the direct flotation effect; On the other hand, if the blast furnace gas ash is directly injected back to the blast furnace for smelting, it is very easy to escape the roasting furnace following the blowing airflow and become ash twice, and the actual effect is not ideal; the blast furnace gas ash has a small particle size and a large specific surface area, so it can be recovered by wet leaching The rate is faster, but the cost of wet recovery is higher, and the economic loss in the process of waste acid treatment of derivative wastewater is greater