Sumitomo Metal Mining Company, Ltd.

Masaki Imamura

Go Ohara

Yasumasa Kan

Yoshitomo Ozaki

Kouji Ando

Naoyuki Tsuchida

Hideki Sasaki

Hiroshi Kobayashi

Keiji Kudo

Hideyuki Okamoto

Kazuyuki Takaishi

Hirotaka Higuchi

Susumu Makino

Yoshiyuki Tanaka

Atsushi Fukui

Osamu Nakai

Hirofumi Shouji

Kenji Takeda

Ryoichi Nakayama

Iichi Nakamura

Atsushi Goda

Sunao Kanesaka

Kazunori Furukawa

There is provided a method capable of effectively reducing the amount of acid used in a leaching step and the amount of a neutralizer used in a final neutralization step while nickel yield in a hydrometallurgical process for nickel oxide ore is not reduced. A method for pre-treating ore slurry according to the present invention is a method for pre-treating ore slurry to be provided to a leaching treatment in a hydrometallurgical process for nickel oxide ore, the method including: a first separation step for separating ore slurry into a coarse particle fraction and a fine particle fraction; a second separation step for separating the coarse particle fraction separated in the first separation step into a heavy specific gravity fraction and a light specific gravity fraction; and a vibration sieving step for separating, by a vibration sieve, the light specific gravity fraction.

Mineral ore slurry pretreatment method, and method for manufacturing mineral ore slurry

Provided is a hydrometallurgical process for nickel oxide ore effectively reducing the amount of sulfuric acid used in the leaching step and the amount of a neutralizer such as slaked lime used in the final neutralization step without reducing nickel yield. The present invention is a method for pre-treating ore slurry to be submitted for leaching treatment in a hydrometallurgical process for nickel oxide ore, the method comprising: a separating step for separating the ore slurry into a coarse particle fraction, in which particles having a particle diameter of less than 45 &#x3bc;m are 30 mass % of the solids or less, and a fine particle fraction, and feeding said fine particle fraction to the leaching process; and a vibration sieving step for separating the separated coarse particle fraction into oversize particles and undersize particles using vibration sieving and feeding the ore slurry of said undersize particles to the leaching process.

Ore slurry pre-treatment method and ore slurry manufacturing method

There is provided a method for producing (high purity) hematite for ironmaking, in a process where a mineral acid and an oxidizing agent are added to an ore containing iron and a valuable metal and then the valuable metal is leached under high temperatures and high pressures, comprises the steps of: (1) a high pressure leach step; (2) a preliminary neutralization step; (3) a solid-liquid separation step 1; (4) a neutralization step 1; (5) a neutralization step 2; (6) a solid-liquid separation step 3; (7) seed crystal addition treatment; (8) a solid-liquid separation step 2; and (9) a firing step.

Method for producing hematite for ironmaking

Proposed is a process for separating a leach residue from which a hematite-containing material that can be used as a raw material for ironmaking can be obtained, and provided is a production process of hematite for ironmaking from the leach residue. The process for producing hematite for ironmaking using, as a raw material, the leach residue in a slurry state obtained from a hydrometallurgical plant for nickel oxide ore utilizing a high pressure acid leach process comprises in sequence: a first step of separating the leach residue in a slurry state into an overflow and an underflow using a wet cyclone; a second step of separating the overflow into a strong magnetic component and a weak magnetic component using a strong-magnetic-field magnetic separator utilizing magnetic force; and a third step of sintering the separated strong magnetic component at a temperature of 1150 to 1350&#xb0; C. to form a sintered body.

Process for producing hemataite for ironmaking

A process is provided for obtaining a hematite-containing material that can be used for ironmaking. The process includes separating a leach residue from a hydrometallurgical refining plant into an overflow and an underflow using a wet cyclone under a condition that the wet cyclone is adjusted to have a setting between 1 &#x3bc;m or less and 2 &#x3bc;m or less as a classification particle size for the overflow. The process then includes separating the overflow into a strong magnetic substance and a weak magnetic substance using a strong-magnetic-field magnetic separator under a condition that magnetic field intensity is 5 to 20 [kGauss]. The process then includes using a superheated steam drying system for adjusting a moisture content of the strong magnetic substance after the separation, to be 10 wt % to 17 wt %.

Process for producing hematite for ironmaking

Provided is a method for producing hematite for ironmaking, capable of using a conventional Ca-based neutralizing agent and a base rock-derived neutralizing agent other than the Ca-based neutralizing agent. The method is performed by a process of adding a mineral acid and an oxidizing agent to an ore containing iron and a valuable metal and then leaching the valuable metal under high temperature and pressure, and includes (1) a high-pressure acid leaching step, (2) a preliminary neutralization step, (3) a first solid-liquid separation step, (4) a neutralization step, (5) a second neutralization step, (6) a third solid-liquid separation step, (7) a step of adding part of the Fe-enriched slurry as a seed crystal in the neutralization step (4), and (8) a second solid-liquid separation step.

A method is provided for separating a leach residue from which a hematite-containing material capable of being used as a raw material for ironmaking can be obtained. A method also is provided for producing hematite for ironmaking from the leach residue. The method utilizes a leach residue as a raw material, the leach residue being obtained from a hydrometallurgical refining plant where a nickel oxide ore treated by a high pressure acid leach process. The method includes, in sequence: a separation step of separating the leach residue into an overflow and an underflow with a wet cyclone; and another separation step of separating the separated overflow into a strong magnetic substance and a weak magnetic substance using magnetic force, wherein a strong-magnetic-field magnetic separator is used in the another separation step using the magnetic force.

A hydrometallurgical process based on pressure leaching at elevated temperature for recovering nickel from nickel oxide ores, characterized by a simplified and efficient process as a whole, realizing a simplified leaching stage, reduced neutralizer consumption and precipitate production in the neutralization stage, and efficient use of recycled water. The hydrometallurgical process of the present invention, comprising a leaching stage which stirs the slurried ore in the presence of sulfuric acid at 220 to 280&#xb0; C. to produce the leached slurry; solid-liquid separation stage which washes the leached slurry in multi-stages to produce the pregnant liquor and leached residue, the former containing nickel and cobalt; neutralization stage which treats the pregnant liquor in the presence of calcium carbonate incorporated to keep the pH level at 4 or less, while suppressing oxidation of the liquor, to produce the neutralization precipitate slurry and mother liquor for nickel recovery, the former containing trivalent iron; and a sulfide precipitation stage which blows hydrogen sulfide gas into the mother liquor to produce the sulfide solution and barren liquor, the former containing nickel and cobalt.

Hydrometallurgical process of nickel oxide ore

A process for efficient separation/recovery of copper involving selective extraction of the copper ion with the aid of an organic extractant from an aqueous chloride solution containing copper and one or more concomitant elements, discharged from an extractive metallurgy of non-ferrous metals or the like, and subsequent stripping. The process of solvent extraction of copper which treats an aqueous chloride solution containing copper and one or more concomitant elements to separate/recover copper, comprising the first step for selective extraction of copper from the aqueous chloride solution by mixing the solution with an extractant of organic solvent composed of tributyl phosphate as the major component after adjusting the solution at an oxidation-reduction potential of 0 to 350 mV (based on an Ag/AgCl electrode), and the second step for stripping of copper by mixing the extractant in which copper is stripped with an aqueous solution.

Process of solvent extraction of copper

By suppressing oxidation of sulfide minerals in sulfide ore due to bacteria or the like, this invention prevents the elution of heavy metals from the sulfide ore, and reduces the decrease in flotation performance when processing sulfide ore that is stored in a stockpile. Also, the invention makes it easier to process acidic wastewater from a stockpile or tailings dumpsite. In order to accomplish this, oxidation of sulfide minerals in sulfide ore is suppressed by adding an antioxidant, which contains plant polyphenol and whose main component is an organic acid that contains a carboxyl group, to the sulfide ore stored in a stockpile or tailings dumpsite.

Anti-oxidation method for sulfide minerals in sulfide ore

The present invention provides a nickel refining method which uses nickel sulfide produced from nickel oxide ore using a hydrometallurgical process, as the raw material, and in which chlorine leaching is performed using a chloride solution, wherein a cementation reaction is caused between the nickel sulfide and copper ions, using copper ions, preferably included in the leaching solution itself, and a portion of the nickel in the nickel sulfide is leached into the solution, and the remaining nickel and copper are left as a residue, and copper and nickel are chlorine leached from this residue, and wherein the cementation reaction is performed with an oxidation-reduction potential as measured by a silver-silver chloride electrode of below &#x2212;20 mV, preferably below &#x2212;100 mV.

Nickel refining method

A method of sulfidation removal of zinc using hydrogen sulfide is provided, desirably at a temperature at 60&#xb0; C. or lower, wherein in a container that is pressurized at 0.1 MPa or less with respect to atmospheric pressure, by making the pH of the solution 1.5 to 4.0, and the concentration of hydrogen sulfide in gas 2 volume % or greater in equilibrium with the hydrogen sulfide dissolved in the solution, the zinc in solution is removed by sulfidation to 1 mg/liter or less.

Sulfidation reaction control method

A copper concentrate obtained by flotation of a high grade copper ore containing chalcopyrite as a main mineral constituent is leached at a temperature of 100&#xb0; C. or higher, and under a pressure greater than atmospheric pressure yielding a copper leachate containing ferric ions of at least 5 g/L and sulfuric acid, and this copper leachate is used in heap leaching or vat leaching of a low grade copper ore, whereby a method of recovering copper economically from a material containing copper is provided.

Process of recovering copper from ore

A solution purification method for an electrolyte comprising the steps of dividing a chelate resin having a volume corresponding to the quantity of Sb and Bi to be adsorbed into a plurality of columns, bringing an electrolyte into contact with the chelate resin in the columns to adsorb the Su and Bi for removing, respectively, and subjecting a predetermined number of columns which have completed adsorption among the plurality of columns, to washing in turn, such that the columns are fed in series with a washing solution.

Solution purification method for electrolyte

A method of purifying a crude nickel sulfate solution to give pure nickel sulfate through solvent extraction, in which the impurities such as cobalt, calcium, magnesium, iron, zinc, copper, sodium, ammonia and others to be in the crude solution are removed while, if necessary, effectively recovering cobalt, and for which the amount of a neutralizer to be used is reduced and the cost of treating wastewater is also reduced includes an extraction step of adding an organic acid extractant to a crude nickel sulfate solution to thereby extract nickel into the extractant to give a nickel-loaded organic phase, followed by a scrubbing step of scrubbing the organic phase as obtained in the previous extraction step with a nickel-containing scrub solution to thereby remove sodium and ammonia from the organic phase; and a second purifying step of adding a crude nickel sulfate solution to the nickel-retaining organic phase as obtained in the previous first purifying step so as to exchange the nickel in the organic phase with the impurities except sodium and ammonia existing in the crude nickel sulfate solution added in this step, thereby giving a purified nickel sulfate solution and an organic phase containing impurities; and optionally a third purifying step of recovering nickel from the organic the organic phase containing impurities as obtained in the second purifying step, and a step of recovering a valuable metal, cobalt from the organic phase containing impurities.

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Tokyo, Japan

Masaki Imamura