Environment-friendly recycling method for abandoned cathode carbon blocks of aluminum electrolysis cell

Abstract

The invention discloses an environment-friendly recycling method for abandoned cathode carbon blocks of an aluminum electrolysis cell. The abandoned cathode carbon blocks are cleaned and crushed and then blended into an aluminum electrolysis carbon anode production system, and fluoride salt in the abandoned cathode carbon blocks is made to enter anode carbon bodies for aluminum electrolysis to be used as a production raw material for anode carbon for aluminum electrolysis. By means of the environment-friendly recycling method for the abandoned cathode carbon blocks of the aluminum electrolysis cell, the abandoned fluorine-containing cathode carbon blocks are successfully disposed, and original storage cost is lowered to zero; meanwhile, useful components such as carbon, Na, Mg, Al, K, Ca and Fe in the original abandoned cathode carbon blocks are successfully recycled in aluminum electrolysis production, waste is turned into wealth, and direct and indirect economic benefits and environmental protection benefits are remarkable.

Description

technical field [0001] The invention relates to a method for recycling and environment-friendly utilization of waste cathode carbon blocks of an aluminum electrolytic cell. Background technique [0002] At present, the main cell type adopted by China's electrolytic aluminum industry is 350-500kA large-scale prebaked anode electrolytic cell, and the average life span is 7-10 years; And the actual weight is about 35 tons. In the normal production process of aluminum electrolysis, the cathode carbon block of the electrolytic cell contains solid electrolyte components due to the penetration of the electrolyte and the adsorption of the cathode carbon block. The chemical composition of the cathode carbon block is analyzed by mass spectrometer as follows: [0003] Analysis table of chemical composition of cathode carbon block after aluminum electrolytic cell stops [0004] [0005] Since the waste cathode carbon block contains fluoride, it must be stored in a special environme...

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Problems solved by technology

[0006] The environmental protection treatment methods currently developed and tested are generally fire treatment, such as used as fuel in the production of cement burning, thermal power generation, etc., and the burned fluoride is converted into complex compounds that are difficult to dissolve in water, which plays a certain role. Environmental protection, but due to technically difficult reasons, it has not been able to form an industrial scale treatment level

[0007] The Na, Mg, Al, K, Ca, and F elements in the waste cathode carbon block are all useful raw materials in the production of electrolytic aluminum, and they are not recycled, which is a waste

In addition, the carbon in the waste cathode is the raw material for making carbon anodes in aluminum electrolysis production. The production cost is much higher than that of ordinary fuels, and it is not economical to burn them as fuel.

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