System and method for treating overhauling slag of aluminum cell by cement kiln bypass incinerating

Abstract

The invention provides a system and method for treating overhauling slag of an aluminum cell by cement kiln bypass incinerating. The system comprises an overhauling slag crushing system, a cement kilnbypass incinerating system, a conversion and dealkalizing system and a cement kiln resourceful treatment system which are sequentially connected. The method comprises the steps of S1, crushing and powdering the overhauling slag; S2, performing cement kiln bypass incinerating and disinfecting; S3, performing conversion and dealkalizing; and S4, performing resourceful treatment on a cement kiln. According to the system and the method, a suspension combined incinerating furnace is arranged at a cement kiln bypass; the crushed overhauling slag is incinerated under the conditions of high temperature, rich oxygen and long staying time, so that carbon materials in the overhauling slag can fully burn, and moreover, cyanide in the overhauling slag can be oxidized to remove the toxicity under high-temperature aerobic and alkaline conditions; the cinder obtained after incinerating of the overhauling slag is washed through alkaline liquid in order to be converted into a mineralizer containing fluorite for the cement kiln, and a caustic soda byproduct can be obtained, and as a result, the harmless, resourceful, ultimate and massive treatment of the overhauling slag of the aluminum cell can beachieved.

Description

technical field [0001] The invention relates to the technical field of hazardous waste treatment in the electrolytic aluminum industry, in particular to a system and method for incinerating and disposing of overhaul slag from an aluminum electrolytic cell by bypassing a cement kiln. Background technique [0002] The overhaul slag of the aluminum electrolytic cell is the solid waste discharged regularly from the aluminum electrolytic cell, and it is a general term for all the waste lining materials and carbon-containing electrode materials removed during the overhaul of the electrolytic cell. Among them, carbonaceous materials include waste cathode carbon blocks and anode carbon particles; waste refractory and thermal insulation materials include a mixture of refractory bricks, thermal insulation bricks, anti-seepage materials and heat insulation boards. During the overhaul of the aluminum electrolytic cell, the waste refractory insulation materials and carbonaceous materials...

AI Technical Summary

Problems solved by technology

[0008] ① Dealing with the overhaul slag of the aluminum electrolytic cell may cause Na to enter the cement kiln 2 O and CaF 2 Excessive, which will cause the cement kiln system crust blockage and other hazards, long-term safe operation risks, and may also cause adverse effects on cement quality

[0009] ②Since most of the waste cathode carbon block is graphitized carbon, and it is also doped with cryolite electrolyte, its combustion performance is very poor, and it may be difficult to burn completely

The system and method for overhauling the slag of the aluminum electrolytic cell provided in this reference document is to burn the powdered powder in a cement kiln to remove toxicity, but this way of processing in a cement kiln has the problem of insufficient combustion, which may exist It affects the long-term safe operation of the cement kiln and the quality of cement clinker, and cannot realize the recovery of useful resources in the overhaul slag of the aluminum electrolytic cell. The project does not meet the requirements of circular economy development, and the technical and economical efficiency of the project is not good

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