Method of extracting electrolyte from waste cathode carbon block of aluminum electrolysis bath

Abstract

A process for extracting electrolytes from waste cathode carbon blocks of aluminum cell is characterized in that the extracting process comprises the following steps: cleaning up, pulverizing and grinding the fire-resistant material adhered to the waste cathode carbon blocks surface of aluminum cell and the connection parts of the cathode steel sticks, adding 1-40% organic anchoring agent therein, stirring them to uniform, and pressing them into gobbet with a certain shapes; adding the waste cathode gobbet into a high temperature furnace, and calcining them at 750-900 DEG C for 4-6 hours to obtain calcination clinker; the calcination clinker, with electrolytes component of more than 97.5% and thimbleful Fe2O3 contained therein, being able to returned directly back to the aluminum cell for use after flour milling. After said processing, the waste cathode carbon blocks can reach the entire harmlessness, and the electrolytes contained in the waste cathode carbon blocks can be extracted effectively, with remarkable economic benefit and environmental benefit.

Description

technical field [0001] A method for extracting electrolyte from spent cathode carbon blocks of an aluminum electrolytic cell, relating to a carbon cathode part of a lining material discarded in the process of electrolytic production of metal aluminum, in particular including waste bottom carbon blocks, waste side carbon blocks and spent cathodes Extraction method of electrolyte in carbon cathode material (excluding waste refractory material) including paste. Background technique [0002] The waste tank lining produced in the production process of electrolytic aluminum contains a large amount of soluble fluoride and cyanide. It is directly stacked in the open air and pollutes the atmosphere. It mixes with rainwater into rivers and pollutes surface water sources, infiltrates underground and pollutes groundwater, and landfills pollute soil. Human health and plant and animal growth. The pollution of waste tank linings has become one of the important issues affecting the compreh...

AI Technical Summary

Problems solved by technology

At present, the treatment methods of waste cathode carbon blocks that have been reported include flotation method and sulfuric acid decomposition method. The technical essence is to use wet process to treat waste cathode carbon blocks, and part of the electrolyte and carbon powder can be recovered during the treatment. There are technical difficulties Yes: (1) Cyanide cannot be removed; (2) Cyanide and some fluoride are transferred into the waste liquid to cause secondary pollution, and the waste liquid cannot be discharged up to the standard

Therefore, the flotation method and the sulfuric acid decomposition method cannot make the spent cathode carbon block completely harmless.

[0004] Because the waste cathode carbon block has the characteristics of C, electrolyte and a small amount of cyanide, the existing technology often cannot effectively extract the high value-added electrolyte in the waste cathode carbon block when the waste cathode carbon block is made harmless, or cannot make the waste cathode carbon block The carbon block is completely harmless, which affects the comprehensive utilization effect of the spent cathode carbon block