Dump leaching processing method for waste cathode inner lining of aluminum electrolytic bath

Abstract

Disclosed is a dump leaching processing method for a waste cathode inner lining of an aluminum electrolytic bath. The dump leaching processing method comprises the following steps that insulating bricks, castables, anti-leakage materials and carbon materials in the waste cathode inner lining which is sorted from bath residues generated in overhaul the aluminum electrolytic bath are correspondingly crushed and screened, the crushed waste insulating bricks, castables, anti-leakage materials are mixed and then processed, and the carbon materials are independently processed; the processing method of mixed materials of the waste insulating bricks, the castables and the anti-leakage materials is the same with the processing method of the carbon materials, and the processing method comprises the following steps of pre-leaching, dump leaching and washing which are conducted circularly; pre-leached liquid and dump leached liquid of the mixed materials are subjected to oxidative decyanide treatment and then are filter-pressed; pre-leached liquid and dump leached liquid of the carbon materials are also subjected to oxidative decyanide treatment and then are filter-pressed; and filter-pressed liquid of the mixed materials and filter-pressed liquid of the carbon materials are mixed and subjected to carbon-neutralization treatment, through concentration and crystallization, sodium salt is recovered, and mixture of fluorinated NaHCO3, fluorinated Na2CO3 and NaF is obtained. By means of the dump leaching processing method, innocent treatment and comprehensive using can be conducted on the waste cathode inner lining of the aluminum electrolytic bath.

Description

technical field [0001] The invention relates to the technical field of treatment methods for aluminum electrolysis waste tank linings. Background technique [0002] The electrolytic cell of the electrolytic aluminum factory is the core equipment for the production of electrolytic aluminum. The waste cathode lining is caused by the penetration and corrosion of the high-temperature electrolyte to the cell lining during the aluminum electrolysis production process, resulting in deformation and cracking of the aluminum electrolytic cell lining structure. , High-temperature aluminum liquid and electrolyte penetrate into the tank lining from these deformed and cracked cracks, resulting in the failure of normal production of the electrolytic tank and the shutdown of the tank for repair. Because the lining of the aluminum electrolytic cell reacts with the electrolyte at high temperature for a long time, it absorbs a large amount of fluoride and a certain amount of harmful substances...

AI Technical Summary

Problems solved by technology

Most electrolytic aluminum enterprises mainly use landfill or storage for waste cathode lining, which not only needs to occupy a lot of land, invest a lot of operating funds and management costs, but also pollutes the ecological environment