Preparation method of high-quality prebaked anode for 500KA electrolytic cell

Abstract

The invention relates to a preparation method of a high-quality prebaked anode for a 500KA electrolytic cell. The method comprises the following steps of: (1) storing petroleum coke at different storage locations according to different producing areas; (2) crushing the petroleum coke blocks having the granularity greater than 200mm with a sledge hammer, sieving the petroleum coke blocks with the granularity less than 200mm, delivering the petroleum coke with the granularity less than 70mm into a petroleum coke conveyer belt, recrushing the petroleum coke with the granularity greater than 70mm so as to deliver the petroleum coke with the granularity less than 70mm into the petroleum coke conveyer belt; (3) feeding different petroleum cokes into a specified blending cabin, wherein the petroleum coke of one producing area is placed in each of the four blending cabins, and a belt weigher is arranged at the bottom of each blending cabin; (4) preparing calcined coke; (5) preparing rough coke, middle coke, fine coke and powdery coke; (6) preparing boiler-out thickeners; (7) preparing cooled thickeners; (8) preparing green bodies; (9) feeding the green bodies into a stacking storeroom for stacking; and (10) roasting the green bodies to obtain a prebaked anode. By using the preparation method, the electrolysis preparation requirement can be met, and safe and sable operation of the electrolytic cell is ensured.

Description

technical field [0001] The invention relates to the field of production of prebaked anodes for electrolytic cells, in particular to a method for preparing high-quality prebaked anodes for 500KA electrolytic cells. Background technique [0002] The 500KA electrolyzer is currently the most advanced ultra-large electrolyzer in my country. It successfully solves the problems of magnetic fluid stability, heat balance and deformation of the tank shell, etc. It has low energy consumption (not higher than 12500KWH / t-Al), current High density (not less than 0.8A / cm 2 ), high current efficiency (not less than 94%). At present, my country's 500KA electrolyzer enterprises that have been built or are under construction include China Aluminum Liancheng Branch, Jiugang Dongxing Aluminum Company, Xinjiang Dongfang Hope Aluminum, Xinjiang Tianshan Aluminum, Xinjiang Xinfa Aluminum, Xinjiang Shenhuo Group, Xinjiang Qiya Aluminum Group, etc. These aluminum plants started construction in 2010 a...

AI Technical Summary

Problems solved by technology

[0003] At present, the production of prebaked anodes for 500KA electrolyzers has the following problems: (1) The particle size of petroleum coke is relatively fine, and there is a secondary crushing problem in the process of crushing petroleum coke; Cars or reloading machines are mixed in the raw material warehouse, the mixing accuracy is low, and the quality of calcined coke fluctuates greatly, especially the fluctuation of trace element indicators; The single block weight reaches 1230kg, and the volatile content is as high as 86.1kg. Each roasting furnace can hold 168 or 147 blocks. The volatile content of raw blocks in each furnace chamber of the roasting furnace reaches 14464.8kg or 12656.7kg, which is higher than that used in electrolytic cells below 500KA. The pre-baked anode is 3292.8kg or 2881.2kg higher, and the volatile matter is not fully burned, causing a large amount of tar to adhere to the smoke exhaust rack, flue and dust collector during the roasting process, causing great fire hazards and poor roasting quality of the product; (4) The prebaked anodes used in the existing 500KA electrolytic cells have a short service life (25 days to 28 days) and a large amount of slag drop (above 10kg / h), which is difficult to meet the current electrolytic production needs