GEM CO., LTD.

Disclosed is a combined treatment method for laterite nickel ore hydrometallurgical slag and phosphating slag, the combined treatment method includes uniformly mixing a laterite nickel ore hydrometallurgical slag, a phosphating slag, and a sodium alkaline salt to obtain a mixed material; subjecting the mixed material to sodium reduction roasting to obtain a roasted material; leaching the roasted material with water and filtering to obtain a water leaching solution and a water leaching slag; subjecting the water leaching slag to magnetic separation to obtain an iron concentrate. In the disclosure, by mixing a laterite nickel ore hydrometallurgical slag and a phosphating slag and then performing sodium reduction roasting, the iron exists in the form of Fe 3 O 4 and elements such as manganese and zinc exist in the slag in the form of oxides, and during the roasting process, aluminum oxides react with alkali to be converted into sodium aluminate.

A dynamic optimization method for acid-to-ore ratio in high-pressure leaching of laterite nickel ore includes: obtaining a feed ore composition, a pulp concentration, a pulp flow rate, a leaching temperature and a pulp duration time in an autoclave, and setting a target leaching rate of nickel; setting a flow rate of sulfuric acid; obtaining a relationship between a hydrogen ion concentration in a solution and a reaction time; obtaining a theoretical leaching rate of nickel when a leaching time reaches the pulp duration time in the autoclave; comparing the theoretical leaching rate of nickel with the target leaching rate of nickel; adjusting the set flow rate of the sulfuric acid until the theoretical leaching rate of nickel is equal to the target leaching rate of nickel, calculating a corresponding optimal acid-to-ore ratio; and adjusting an opening degree of a sulfuric acid flow regulating valve of the autoclave.

A treatment method for laterite nickel ore by curing and roasting-water leaching-atmospheric pressure acid leaching is provided. The treatment method includes the following steps: mixing a laterite nickel ore dry powder, concentrated sulfuric acid, and sodium fluoride uniformly, performing curing and roasting under a reducing atmosphere to obtain a cured material; performing water leaching on the cured material to obtain a water leaching solution and a water leaching slag after filtration; and performing atmospheric pressure acid leaching on the water leaching slag to obtain an acid leaching solution and an acid leaching slag after filtration.

A method for green and low-cost extraction of nickel-cobalt from laterite nickel ore includes: (1) iron removing pretreatment: adding an iron removing agent to a high-pressure leaching solution of the laterite nickel ore to reduce an iron concentration to less than 0.2 g/L to obtain a laterite nickel ore leaching solution; (2) nickel adsorption: adsorbing and enriching nickel in the laterite nickel ore leaching solution using a first resin adsorption process to obtain a nickel adsorption resin and a nickel adsorption tail liquid; wherein the nickel adsorption resin is desorbed to obtain a crude nickel solution; (3) cobalt adsorption: subjecting the nickel adsorption tail liquid to cobalt adsorption and enrichment by a second resin adsorption process to obtain a cobalt solution by desorbing; (4) copper adsorption: subjecting the crude nickel solution to a third resin adsorption process for removing copper to obtain a purified nickel solution.

Disclosed is a method for continuously preparing mixed hydroxide precipitate from a laterite nickel ore by hydrometallurgy. Primary-precipitated mixed hydroxide precipitate particles are used as crystal nuclei, by controlling precipitation process conditions, the quantity of the crystal nuclei, and reaction time of the crystal nuclei, primary mixed hydroxide precipitate crystal nuclei gradually grow, and crystal forms become larger. By controlling the number of cycles, a proportion of returned seed crystals, and a homogenization ratio with precipitants, mixed hydroxide precipitate particles with narrow particle size distribution, dense particles, and better sedimentation effect are obtained, thereby reducing a moisture content of mixed hydroxide precipitate. The preparation method in this disclosure plays a certain guiding role in practical production and has good application prospects.

A wastewater treatment process in the production of nickel cobalt hydroxide includes the following steps: S 1 . subjecting a laterite nickel ore acid-leaching solution successively to iron-aluminum removal and nickel-cobalt precipitation to obtain wastewater; S 2 . subjecting the wastewater successively to chromium ions, manganese ions, and silicon ion removal treatments to obtain a suspension; and S 3 . reusing portion of the suspension and continuing iron-aluminum removal; subjecting the remaining suspension successively to homogenizing, alkali adjusting, standing still, CCD counter-current washing, and solid-liquid separation to obtain a supernatant and a residue phase, collecting the residue phase, and discharging the supernatant after neutralization. This method used to treat the laterite nickel ore wastewater can meet the discharge standard, with high safety.

A process and system for recovering manganese from a high-pressure leaching system of laterite nickel ore, including the following steps: S1. adding limestone to the high-pressure leaching solution of the laterite nickel ore for pre-neutralization to obtain first-stage carbon dioxide and a neutralization solution, adding limestone for precipitation of iron and aluminum to obtain second-stage carbon dioxide and a slurry, and adding liquid alkali to the slurry for precipitation of nickel-cobalt-manganese to obtain nickel-cobalt-manganese hydroxide and a nickel-cobalt-manganese precipitated lean solution; S2. collecting first-stage carbon dioxide and second-stage carbon dioxide and passing same into a nickel-cobalt-manganese precipitated lean solution, adjusting the pH value of the nickel-cobalt-manganese precipitated lean solution to 5-6.5 by liquid alkali, and then performing a precipitation reaction to obtain a crude manganese carbonate; S3. dissolving the crude manganese carbonate with sulfuric acid to obtain a dissolution liquid and third-stage carbon dioxide, then removing calcium and magnesium from the dissolution liquid to obtain a manganese sulfate solution and then evaporating and crystallizing to obtain manganese sulfate crystals; recycling the third-stage carbon dioxide and introducing same into a nickel-cobalt-manganese precipitated lean solution; the recovery rate and utilization rate of manganese is high, and the carbon emission from laterite nickel ore leaching process is reduced.

Disclosed is a treatment system for the slag phase after removing iron-aluminum-chromium from leaching solution of laterite nickel ore, comprising a filtering module, a refining module, a feeding module, and a measurement module. The filtering module comprises a material suction component and a filtering assembly. The filtering assembly is connected to the outlet of the material suction component and features a filter residue outlet and a filtrate outlet. The refining module is connected to the filter residue outlet. The feeding module consists of a material pipe and a material guiding drive component. The material pipe has an inlet end connected to the outlet of the refining module. This setup enables the timely filtration of the generated slag phase, followed by refinement processing, and allows for the controlled metering of the returned filter residue. Consequently, it enhances the subsequent acid leaching and dissolution efficiency of the slag phase.

Disclosed is a combined heat exchange system of flash tank and preheater for laterite nickel ore leaching. The system comprises a high-pressure reactor, preheating towers, and flash tanks. The preheating tower is connected to the feed inlet of the high-pressure reactor. The flash tank is connected to the discharge outlet of the high-pressure reactor, and it is also connected to the preheating tower. Inside the flash tank, there is a pressure relief chamber and a buffering mechanism. The buffering mechanism comprises a buffering component and a connecting structure that are interconnected. In this disclosure, the buffering component of the pressure relief chamber is equipped with a central bulge and a buffering tank, materials falling from the pressure relief chamber can sequentially pass over the central bulge and slide from one end of the buffering tank to the other, then slide upwards out of the tank, achieving a buffering effect.

A system for optimizing duration time of high-pressure leaching of laterite nickel ore, includes a data collecting module, an actual duration time calculating module configured to obtain an actual duration time of the pulp in the autoclave during the high-pressure leaching process, an optimal duration time determining module configured to obtain an optimal duration time corresponding to a maximum income value, according to the qualities of the pulp, and a duration time control module configured to compare an actual duration time with the optimal duration time under this condition, and control opening degrees of a feed valve and a discharge valve of the autoclave by using a feedback control system, to ensure the actual duration time of the pulp in the autoclave is within the optimal duration time all the time.