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CN-114622102-B - Method for comprehensively extracting valuable metals from laterite-nickel ore

CN114622102BCN 114622102 BCN114622102 BCN 114622102BCN-114622102-B

Abstract

The invention discloses a method for comprehensively extracting valuable metals from laterite-nickel ores, which comprises the steps of ball milling the laterite-nickel ores, thickening to obtain underflow, adding sulfuric acid for presoaking to obtain slurry, adding the slurry into the mixed ores, performing pressure leaching to obtain first leaching solution and first leaching slag, performing neutralization reaction on the first leaching slag, performing solid-liquid separation to obtain second leaching slag and second leaching solution, and (3) performing acid washing, extraction, washing, back extraction and precipitation on the second leaching slag to obtain scandium hydroxide, and performing alkalinization impurity removal and complexation precipitation on the second leaching solution to obtain cobalt manganese nickel hydroxide. The method has the advantages of low investment cost, low acid consumption and high recovery rate of valuable metals.

Inventors

  • XU KAIHUA
  • LI QINXIANG
  • WANG WENJIE
  • ZHANG KUN
  • ZHU SHAOWEN

Assignees

  • 荆门市格林美新材料有限公司
  • 荆门市格林美新材料有限公司

Dates

Publication Date
20260421
Application Date
20201214
Priority Date
20201214

Claims (6)

  1. 1. A method for comprehensively extracting valuable metals from laterite-nickel ores, which is characterized by comprising the following steps: (1) Ball milling and thickening the laterite-nickel ore to obtain underflow, and adding sulfuric acid to perform presoaking to obtain slurry; (2) Adding the slurry obtained in the step (1) into a matched ore, performing pressure leaching to obtain a first leaching solution and a first leaching slag, performing a neutralization reaction on the first leaching slag, and performing solid-liquid separation to obtain a second leaching slag and a second leaching solution, wherein the mass ratio of the added matched ore to the laterite-nickel ore obtained in the step (1) is 0.4-1.5:1, the leaching temperature is 185-210 ̊ ℃, the leaching time is 1.5-2 h, and the pressure is 1.6-2.5 MPa; (3) Carrying out acid washing on the second leaching slag obtained in the step (2) and sulfuric acid according to a solid-to-liquid ratio of 1:1-1:5 to obtain acid washing liquid, wherein the acid washing pH is 0-1, the acid washing time is 0.5-4H, the acid washing temperature is 60-100 ̊ C, and the acid washing times are 1-5; extracting the extractant and the diluent in the pickling solution to obtain a loaded organic phase and raffinate, and merging the raffinate into the second leaching solution; the extraction agent is one or more of P204, P507 and TBP, the diluent is sulfonated kerosene, the extraction agent is 1% -30% of the diluent, the ratio of water phase to oil phase is 10:1-30:1, the extraction time is 3-30 min, and the standing time after extraction is 5-30 min; adding a detergent into a loaded organic phase obtained through extraction phase separation, wherein the concentration of the detergent is 1-8 mol/L in terms of [ H+ ] concentration, the water phase in the washing process is 1:1-1:30 in terms of oil phase ratio, the washing temperature is 10-90 ℃, the washing time is 5-30 min, the washing times are 1-10 times, adding a stripping agent into the loaded organic phase obtained through the washing phase separation, adding a liquid alkali in terms of [ OH- ] concentration, the concentration of the liquid alkali is 1-10 mol/L, the stripping water phase is 1:1-1:30 in terms of [ H+ ], the stripping time is 3-30 min, the standing time is 5-30 min after stripping, the adopted precipitant is sulfuric acid or hydrochloric acid, the pH value of the water phase obtained through the stripping phase is controlled to be 8-11, the reaction time is 0.5-4H, the alkalizing impurity removing agent is added into the second alkalizing impurity removing agent obtained through the step (2), the alkalizing impurity removing agent is performed, the pH value of the alkalizing liquid is 5-5.5, the pH value of the alkalizing impurity removing agent is 532.5-5, the pH value of the alkaline removing solution is 532.5-5.5, adding complexing agent and precipitant into the solution obtained after the removal of impurities by alkalization for complex precipitation, wherein the complexing agent is ammonia water, the addition amount of the ammonia water is 10% of that of the second leaching solution, the precipitant is magnesium oxide, the reaction temperature is controlled to be 40-80 ̊ ℃, the pH value is 7.0-9.0, the reaction time is 2-8 hours, cobalt manganese nickel is obtained, the solution obtained after the precipitation by complex precipitation enters an ammonia recovery system for ammonia water recovery, the evaporation temperature is controlled to be 80-150 ̊ ℃, and the recovered ammonia water is recycled.
  2. 2. The method of claim 1, wherein the ball milling is performed in the step (1) for 0.5-2 hours, the particle size is 200-300 meshes, the concentration is 20-45% of underflow concentration, the content of suspended matters in overflow is 0-1000 ppm, the mass ratio of sulfuric acid to laterite-nickel ore is 1:2-1.5:1, the presoaking temperature is 70-100 ̊ ℃ and the presoaking time is 2-6 hours.
  3. 3. The method of claim 1, wherein the ore blending of step (2) is brown iron ore layer, transition layer laterite-nickel ore or magnesia laterite-nickel ore.
  4. 4. The method according to claim 3, wherein when the laterite-nickel ore and the ore blend to be pre-impregnated are both limonite layers, the pressure is 1.6-2.5 MPa, the leaching time is 1.5-2 hours, and when either one of the laterite-nickel ore and the ore blend to be pre-impregnated is transition layer laterite-nickel ore or magnesium laterite-nickel ore, the leaching time is 1.5-2 hours, the total pressure is 1.6 MPa-2.5 MPa, and the oxygen partial pressure is 0-35% of the total pressure.
  5. 5. The method according to claim 3 or 4, wherein the limonite layer comprises 0.9-1.5% of nickel, 35-45% of iron and less than 5% of magnesium, the transition layer laterite-nickel ore comprises 1.3-1.7% of nickel, 20-30% of iron and 5-10% of magnesium, and the magnesia laterite-nickel ore comprises 1.7-2.5% of nickel, 5-20% of iron and 8-30% of magnesium.
  6. 6. The method according to claim 1 or 2, wherein the first leaching residue in the step (2) is subjected to a neutralization reaction by using 15-30% calcium carbonate slurry, and the neutralization reaction is performed under the process conditions that the pH of the neutralization reaction is 1-2, the neutralization reaction temperature is 60-100 ̊ ℃, and the neutralization reaction time is 0.5-2 hours.

Description

Method for comprehensively extracting valuable metals from laterite-nickel ore Technical Field The invention belongs to the field of hydrometallurgy, and particularly relates to a method for comprehensively extracting valuable metals from laterite-nickel ores. Background The nickel resource mainly comprises nickel sulfide ore and nickel oxide ore, wherein the nickel sulfide ore accounts for 40 percent and the nickel oxide ore accounts for 60 percent. With the development of society, high-grade easy-to-process nickel sulfide ores are increasingly consumed and exhausted, and the demands of people for nickel resources are gradually shifted to oxidized laterite-nickel ores with more reserves. The laterite-nickel ore layers are distributed from top to bottom and are respectively a limonite layer, a transition layer and a residual layer, and mainly comprise valuable metals such as nickel, cobalt, manganese, scandium and the like, wherein the limonite layer mainly comprises high-iron laterite-nickel ores with the nickel content of 0.9-1.5%, the iron content of 35-45% and the magnesium content of less than 5%, the transition layer mainly comprises transition layer laterite-nickel ores with the nickel content of 1.3-1.7%, the iron content of 20-30% and the magnesium content of 5-10%, and the residual layer mainly comprises magnesium laterite-nickel ores with the nickel content of 1.7-2.5%, the iron content of 5-20% and the magnesium content of 8-30%. The magnesium laterite-nickel ore is usually smelted by adopting a fire method for producing stainless steel, the transition layer laterite-nickel ore is usually used as a mineral preparation raw material for producing stainless steel, and the limonite layer is mainly prepared into a nickel intermediate product by adopting a wet process or a fire-wet combined process. The wet smelting process of laterite nickel ore mainly includes pressurized ammonia leaching, pressurized acid leaching, normal pressure leaching, heap leaching and the like. The pressurized ammonia leaching is represented by a Caron process, namely, the laterite-nickel ore is subjected to pretreatment such as drying, grinding and the like, then is reduced, and then is subjected to ammonia leaching. Mainly has the defects of high energy consumption, low nickel-cobalt recovery rate, capability of only treating laterite-nickel ores with iron content of more than 35 percent, and the like. The main process of the pressurized acid leaching technology comprises the steps of ore sample preparation, pressurized acid leaching, CCD washing (continuous countercurrent washing), neutralization, impurity removal, nickel cobalt precipitation and the like. High investment cost, harsh operating conditions, easy corrosion of equipment, high maintenance cost of the autoclave, long debugging time and inapplicability to minerals with high magnesium content. The normal pressure leaching is mainly carried out by combining seawater ball milling and reduction leaching under normal pressure, the acid consumption in the leaching process is high, and a large amount of impurities such as iron, aluminum, chromium and the like are introduced. The heap leaching process also has the problems of high acid consumption, long period, low metal solution content, high iron and aluminum impurities and the like. Disclosure of Invention Aiming at the defects existing in the prior art, the invention provides a method for comprehensively extracting valuable metals from laterite-nickel ores, which has low investment cost, low acid consumption and high leaching rate of the valuable metals. The invention is realized by the following technical scheme. A method for comprehensively extracting valuable metals from laterite-nickel ores, which is characterized by comprising the following steps: (1) Ball milling and thickening the laterite-nickel ore to obtain underflow, and adding sulfuric acid to perform presoaking to obtain slurry; (2) Adding the slurry obtained in the step (1) into a matched ore, performing pressure leaching to obtain a first leaching solution and a first leaching slag, performing a neutralization reaction on the first leaching slag, and performing solid-liquid separation to obtain a second leaching slag and a second leaching solution, wherein the mass ratio of the added matched ore to the laterite nickel ore (dry ore) obtained in the step (1) is 0.4-1.5:1, the leaching temperature is 185-210 ̊ ℃, the leaching time is 1.5-2 h, and the pressure is 1.6-2.5 MPa; (3) And (3) carrying out acid washing, extraction, washing, back extraction and precipitation on the second leaching slag obtained in the step (2) to obtain scandium hydroxide, and carrying out alkalization impurity removal and complexation precipitation on the second leaching liquid obtained in the step (2) to obtain cobalt manganese nickel hydroxide. Further, ball milling is carried out in the step (1), wherein the time is 0.5-2 h, and the particle size is 200-300 meshes; The conce