Method for leaching nickel-cobalt raw material by roasting SO2-containing tail gas by using molybdenum concentrate

Abstract

The invention discloses a method for leaching a nickel-cobalt raw material by roasting SO2-containing tail gas by using molybdenum concentrate. The method comprises the following steps that water is added into the nickel-cobalt raw material to be mixed, stirred and sizing mixing is carried out for later use, the SO2 tail gas generated by the roasting is guided into an absorption tank, and the SO2emission standard is reached after the SO2 tail gas is continuously absorbed for 3-4 stages; and in the absorption process, the nickel-cobalt is combined with S to form sulfate while the nickel-cobaltis leached, a nickel-cobalt leachate enters a subsequent impurity removal process. According to the method, the SO2 tail gas with low concentration can be discharged after being purified and absorbed, meanwhile, the leaching of the nickel-cobalt raw material is realized, and finally, the nickel-cobalt containing of final leached slag is lower than 0.5%.

Description

technical field [0001] The invention belongs to the technical field of molybdenum concentrate roasting tail gas treatment, and relates to a method of roasting molybdenum concentrate containing SO 2 A method for leaching nickel and cobalt raw materials with tail gas. Background technique [0002] The main component of molybdenum concentrate is MoS 2 , wherein the S content accounts for about 30% to 40%, and almost all industrialized molybdenum smelting requires high-temperature roasting by fire method and then wet leaching. According to production requirements, S in molybdenum oxide after roasting is ≤ 0.1%, and a large amount of it combines with oxygen in the air during roasting to form SO 2 Outward emission, SO in exhaust gas 2 The concentration is about 0.5% to 2%, containing SO 2 If the exhaust gas is directly emptied without treatment, it will be extremely destructive to the environment. Currently available SO 2 Tail gas treatment methods mainly include: traditiona...

AI Technical Summary

Problems solved by technology

The disadvantage is that the process is complicated, and the SO in the tail gas 2 When the concentration fluctuates greatly, the amount of lime is difficult to control, and the formed CaSO 3 The formation of wrapping on the surface of CaO directly affects the SO 2 Adsorption effect, and the waste residue generated at the same time is piled up, which is easy to cause secondary pollution

[0005] 3. After the roasting flue gas is dust-collected, sulfuric acid is produced. The practice at home and abroad has proved that with about 1% SO 2 Although it is technically feasible to produce dilute sulfuric acid from flue gas, it is economically uneconomical

[0006] 4. Soda ash absorbs SO 2 Preparation of sodium sulfite requires large consumption of soda ash, high energy consumption in the crystallization process, low product value, and uneconomical

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