Method for treating cold-state lead-rich slag with hot slag side-blowing reduction furnace

Abstract

The invention relates to a method for treating cold-state lead-rich slag with a hot slag side-blowing reduction furnace, and belongs to the technical field of thermometallurgy. The method comprises the following steps: (1) adding 70-90 t of hot-state lead-rich slag, 3-6 t / h of cold-state lead-rich slag, 1.5-2.5 t / h of limestone, 3-4 h / t of iron calcine, 2-3 t / h of coke nut and 0.8-1.6 t / h of crushed coal; (2) after a siphon mouth lead liquid level rises to the lead liquid flowing height in a lead-rich slag adding process, carrying out lead tapping and ingotting; (3) adding 3-10 t of zinc calcine, 2.2-3.5 t of limestone, 3-6 t of iron calcine, 2-3.5 t of coke nut, and 2.5-4 t of crushed coal into each furnace, and controlling the gas flux, oxygen flux, molten pool temperature and in-furnace negative pressure within 3200 to 3600 Nm<3> / h, 950 to 1200 Nm<3> / h, 1100 to 1300 DEG C and -20 to -40 pa respectively; (4) after the lead-rich slag adding process is finished, continuously adding crushed coal at 1000-1250 DEG C for 1-2 hours' smelting, observing the lead content of molten slag with a slag detection bar till the lead content is lower than or equal to 2.2%, and then carrying out 0.5 hour's heating for slag tapping; (5) conducting waste heat recovery and dust collection on flue gas in a smelting process, and then sending the treated flue gas into a desulphuration system. The method is simple in technology and has the advantages that the conventional technology is sufficiently utilized, the defect in stockpiling of the cold-state lead-rich slag is effectively overcome, the recovery rate of valuable metal is improved, and the like.

Description

technical field [0001] The invention relates to a method for treating cold lead-rich slag with a hot slag side-blown reduction furnace, belonging to the technical field of pyrometallurgy. Background technique [0002] Cold lead-rich slag is the cold slag obtained by cooling the high-lead hot slag produced during the smelting and oxidation process of lead sulfide concentrate, generally containing 40-55% lead, mainly produced by oxygen-enriched top-blown furnace or oxygen-enriched bottom furnace. Furnace output. Cold lead-rich slag is often used as raw material for blast furnaces. The disadvantages are that lead-rich slag is produced by oxidation smelting, the continuity of the production process is weak, and the comprehensive utilization of heat energy is poor, which is not conducive to energy saving and emission reduction. With increasing attention, the blast furnace lead smelting process has been banned as an eliminated process. In the lead smelting process of oxygen-enri...

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Problems solved by technology

Cold lead-rich slag is often used as raw material for blast furnaces. The disadvantages are that lead-rich slag is produced by oxidative smelting, the continuity of the production process is weak, and the comprehensive utilization of heat energy is poor, which is not conducive to energy saving and emission reduction. With increasing attention, the blast furnace lead smelting process has been banned as a phase-out process

In the lead smelting process of oxygen-enriched top-blown or side-blown reduction furnace and oxygen-enriched bottom-blown reduction furnace for lead smelting, due to production failures, maintenance operations and other reasons, there will always be a part of cold lead-rich slag. Heat is absorbed during the melting process, which affects the stability of the reduction furnace, thereby limiting the treatment of cold lead-rich slag. On the one hand, long-term storage causes waste of resources, affects the comprehensive recovery of valuable metals, and increases the burden of on-site warehouse storage. There is no introduction to the process of treating cold lead-rich slag with lead smelting reduction furnace at home and abroad

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