Method for producing aluminum anode by using waste cathode carbon block of aluminum cell

Abstract

The invention relates to a method for producing an aluminum anode by using a waste cathode carbon block of an aluminum cell, belonging to the technical field of non-ferrous metallurgy environmental protection. The method comprises the following steps of: (1) crushing the waste cathode carbon block of the aluminum cell and sorting a steel rod, a refractory material, an electrolyte and the like in the waste cathode carbon block; (2) performing coarse crushing on the sorted waste cathode carbon block of the aluminum cell; (3) grinding into powder less than 0.075 millimeters; (4) separating impurities in the waste cathode carbon block of the aluminum cell by adopting methods including a floatation method, an acid method, an alkali method, an acid-alkali combination method and the like; (5) drying the treated waste cathode carbon block powder of the aluminum cell; (6) mixing according to the formula requirement of aluminum anode production; and (7) entering an aluminum anode production system and mixing the powder to produce a pre-baked anode. In the method, the waste cathode carbon block of the aluminum cell is taken as mixing powder for the aluminum anode, so that harmless treatment and comprehensive utilization of the waste cathode carbon block of the aluminum cell are realized, the using amount of petroleum coke is reduced, resources are saved, and the production cost is lowered.

Description

1. Technical field [0001] The invention relates to an application method of a waste cathode carbon block of an aluminum electrolytic cell, and belongs to the technical field of nonferrous metal metallurgy and environmental protection. 2. Background technology [0002] The waste cathode carbon block used in the aluminum electrolysis process generally contains carbon, sodium fluoride, cryolite, aluminum fluoride, calcium fluoride, alumina, etc., of which the carbon content is about 50-70%, electrolyte (including fluoride salt and alumina ) is about 50-30%, and the cyanide content is about 0.2%; the fluorine content of the leaching solution of the solid waste of electrolytic aluminum cathode furnace materials (mainly cathode carbon blocks and refractory materials) can reach 6000 mg / L, CN - The content can reach 10-40 mg / L, exceeding the standard requirements of the national "Hazardous Waste Identification Standard-Leach Toxicity Identification" (F - <50mg / L, CN - >1 mg / ...

AI Technical Summary

Problems solved by technology

[0006] The article "Recycling and Utilization of Waste Cathode Lining of Aluminum Electrolytic Cells" published in the fourth issue of 2001 in "Mineral Protection and Utilization" mentioned that there are foreign attempts to use waste cathodes as anode paste ingredients in aluminum electrolysis production. Using waste cathodes as anode paste batching aggregates, waste cathode carbon blocks are directly used for anode paste batching without ash removal after crushing, and the blending ratio of waste cathode carbon blocks is below 4.5% (wt), which cannot make full use of waste cathodes Carbon blocks are used as aggregates. Due to the large difference in activity with binders, petroleum coke, and pitch coke, the aggregates of waste cathode carbon blocks have serious slag loss.