Method of ore heap leaching
SUBSTANCE: invention relates to method of metals heap leaching, notably, gold from ore. Method includes ore reduction, ore division into fractions, ore dump by uniform in fractions inclined layers with reduction of ore fineness from the low layer to top with separation of layers by perforated polymer film. Then it is implemented stack irrigation by leaching cyanide solution with concentration 0.2-0.8 g/l. Additionally after dump of each ore leaching it is implemented treatment of layer by cyanide solution with strengthen concentration and its standing. Concentration of cyanide solution and standing duration are reduced from low later to top from 2.0-4.0 g/l till 1.0-1.5 g/t and from 5-6 days till 2-3 days correspondingly.
EFFECT: leaching effectiveness increase.
The invention relates to the field of leaching of ores of nonferrous, rare and radioactive metals and can be used in the mining industry, mainly in the extraction of gold.
Known methods of heap leaching of ores, including todopoderoso, the formation of stacks of ore, irrigation stacks of ore leaching solution, the infiltration of the solution into an array of stacks, the dissolution of metal and drainage enriched solvent. As leaching solutions used water (for uranium ores containing pyrite), weak solutions of sulphuric acid, a solution of iron sulfate and sulfuric acid, soda solution, sodium cyanide and other (see Kalabin A.I. Mining underground leaching): Atomizdat, 1969, P.95-319; Rysev VP, Sadykov, BC, Fazlullah M.I. Experience in heap leaching of gold Gorn. - 1994. No. 12 - p.8-10).
The disadvantage of this method is to reduce the rate of leaching and the completeness of extraction of metal due to clogging of the pore space at the bottom of the pile due to segregation pieces of ore and sufoziya (transfer) of fine particles (clay, silt) from the top of the pile at the bottom. At low outside temperatures the rate of leaching is also sharply decreases due to the increase in the viscosity of the leach solutions.
The closest to perfect UEMOA is a method of heap leaching of gold, include ore crushing, ore pelletizing, dumping stacks, application of stacks of ore leaching solution. After crushing the ore into fractions, and the dumping of ore carry out homogeneous fractions layers, reducing the particle size of the ore from the lower layer to the upper layer. In addition, the dumping of ore implement inclined layers with separation of perforated layers of geotextile material, in dumping the pile guide the wider side to the South (see U.S. Pat. Of the Russian Federation No. 2283879, IPC SW 3/04, SW 11/00).
However, this method of heap leaching clay slime ores in General improve the filtration properties of the pile can be characterized by a lack of extraction of metal from the lower layers of coarse fraction (+15)...(-20) mm, (+10)...(-15) mm, (+5)...(-10) mm due to the relatively short time of contact with the surface of the lumps of ore leach solutions because of the high speed filtration in these layers.
The technical result of the invention is to improve the efficiency of leaching.
The result is achieved that the method of heap leaching of gold from ores, which includes ore crushing, ore separation into fractions, dumping ore homogeneous fractions of the inclined layers with decreasing particle size of the ore from the lower layer to the upper layer division of a perforated polymer film and the irrigation of the pile is selecively solution after filling each layer produce ore processing layer cyanide solution of high concentration and maturation within 2-6 days, and the concentration of the cyanide solution and the duration of maturation decrease from the bottom layer to the top.
Pre-treatment osypaemy layers cyanide solutions of high concentration and subsequent exposure can increase the completeness of extraction of metal, in particular of large fractions of classes (+15)...(-20) mm, (+10)...(-15) mm in the lower layers due to the deep diffusion of the concentrated leach solution and the entry into the reaction of cyanide complexes of gold. Further leaching of the pile is actually reduced to the washout of previously prepared reacted ore leach solutions.
The drawing shows a stack, where 1 is the bottom layer of the stack (fraction (+15)...(-20) mm; 2 - layer stacks of fraction (+10)...(-15) mm; 3 - layer stacks of fraction (+5)...(-10) mm; 4 - layer stacks fraction (-5) mm; 5 - irrigation and power stacks; 6 - lateral surface of the pile of ore; 7 - collectors collection process solutions; 8 - base of the pile; 9 - perforated polymer film.
The method is as follows.
When radiopathology on the crushing and sorting plant (DSU) of the extracted ore is crushed and separated into fractions, typically the class is am (-5,0) mm, (+5)...(-10) mm, (+10)...(-15) mm and (+15)...(-20) mm Dumping stacks start with a layer of ore fractions (+15)...(-20) mm 1, produce its irrigation leaching solution with a high concentration of cyanide...4,0 2,0 g/l to complete vlagonasyschennyh produce aged for 5...6 days. Then stack a perforated polymer film 9 and occiput layer of ore fractions (+10)...(-15) mm 2 and irrigate his leach solution with a concentration of cyanide 1.5 to 2.5 g/l to complete vlagonasyschennyh and stand for 4 to 5 days. After that stack perforated film 9 and occiput the next layer of ore fractions (+5)...(-10) mm 3, irrigate its leaching solution high concentration of cyanide 1...2 g/l to complete vlagonasyschennyh and stand for 3 to 4 days. Then stack perforated film 9 and occiput the top layer of ore 4 small fraction class (-5,0) mm and irrigate his leach solution concentration of cyanide 1...1.5 g/l to complete vlagonasyschennyh and stand within 2 to 3 days. After that, on the surface of the top layer 4 is placed stationary irrigation system and power supply 5 and proceed to continuous irrigation stacks of ore leach solution concentration of cyanide according to the technological regulations - usually 0,2...0,8 g/l
Under irrigation, the leaching solution of clay and slurry particles are leached from the upper layers in h is life and under the action of dynamic pressure taken out through the perforated film 9 and the side surface 6 stacks of ore, as a result of this prevents clogging of the ore in the array of stacks and increases the rate of filtration of leach solution. When passing a leaching solution through the lower layers are actually leaching the reacted during the settling of ore cyanide complexes, resulting in increased metal recovery. The pregnant solution is collected 7 and after cleaning it from the clay particles being filtered is directed into the sorption apparatus for metal recovery.
The proposed method can improve the efficiency by increasing the rate of filtration of the leach solution in the sample and more complete extraction of the metal from krupnomasshtabnykh layers of ore due to their preliminary cyanide training.
Method of heap leaching of gold from ores, which includes ore crushing, ore separation into fractions, dumping ore homogeneous fractions of the inclined layers with decreasing particle size of the ore from the lower layer to the upper layer division of a perforated polymer film, irrigation pile of barren cyanide solution with a concentration of 0.2-0.8 g/l, characterized in that after filling each layer of ore are processed layer cyanide solution of high concentration and maturation of it, with the concentration of the cyanide solution and continue inost maturation decrease from the bottom layer to the top from 2.0-4.0 g/l to 1.0-1.5 g/t and from 5-6 days to 2-3 days respectively.
SUBSTANCE: it is implemented treatment of copper-nickel sulfide concentrate by fluoride and/or ammonium bifluoride at the temperature 165-210°C during 2-3 hours with forming of hard fluorination products and emission of ammonia gas and water vapor. Fluoride and/or ammonium bifluoride are used in amount 1.0-1.2 from stoichiometric with respect to overall content in copper-nickel concentrate of silicates and pyrrhotine. Hard fluorination products exposed to water leaching at the temperature 40-60°C and S:L=1:5-6 during 1-2 hours with transformation to residue nickel sulfide, copper, cobalt, platinum metal and magnetite, and into solution - fluorine-ammonium silicon saline, magnesium, iron, aluminium and calcium. Residue is separated from solution and exposed to magnetic separation with magnetite extraction. Received solution is neutralised by ammonia water till providing of pH 8-10 with regeneration of fluoride and/or ammonium bifluoride and receiving of residue of magnesium, iron, aluminium, calcium and silica hydroxides. In the capacity of ammonia water for solution neutralisation can be used ammonia gas and water vapors from the stage of raw materials fluorination. Formed ammonium fluoride and/or bifluoride are returned to raw materials treatment stage.
EFFECT: energy content reduction and providing of selectivity sulfide crude ore treatment at less number of operations.
5 cl, 1 dwg, 4 ex
SUBSTANCE: method of metal extraction recovery from solid-phase of raw-materials includes crushing of raw materials, leaching by means of direct microemulsion, consisting of aqueous phase and organic phase, containing kerosene in the capacity of extractant di-(2-ethylhexyl) sodium phosphate, separation of solid phase and re-extraction of recovered metals. At that leaching is implemented by microemulsion, consisting of 30-75% turn of aqueous phase and containing in organic phase di-(2- ethylhexyl) sodium phosphate in amount 1.0-2.0 mole/l and additionally introduced di-(2-ethylhexyl) phosphoric acid in amount 0.3-0.6 mole/l. Into compound of organic phase of microemulsion i can be additionally introduced aliphatic alcohols in amount till 5% turns.
EFFECT: ability of selective extraction of nonferrous and rare metals raw at leaching stage, without usage of concentrated acid and expensive organic solvent.
9 tbl, 7 ex
SUBSTANCE: invention concerns methods of residue utilisation. Particularly it concerns method of copper extraction from sulphate containing dust of copper production. Method includes water leaching of dust with copper and impurity elements conversion into leaching solution, separation of solution from insoluble residue, liquid solvent extraction of copper by oximne extractant with receiving of copper-bearing extract and raffinate, containing impurity elements. After extraction it is implemented copper re-extraction, cleaning of received re-extract from extragent and electro-extraction of copper with receiving of commercial copper and reversible electrolyte. At that water leaching of dust is implemented at temperature 60-100°C and H:L=1:2-4. Leaching solution is cooled with crystallisation of copper main part in the form of vitriol and forming of mother solution, containing residual part of copper. Vitriol is separated from mother solution, dissolved in sulphuric solution and fed to electro-extraction, and liquid solvent extraction is implemented from mother solution.
EFFECT: receiving of qualitative cathode copper of grade MOOK with yield into commercial product up to 98% of copper at high (90,5-93,5%) yield by stream, and also in reduction of material flow volume and deep separation of copper from impurity elements.
9 cl, 3 ex
SUBSTANCE: invention concerns processing method of copper manufacturing dust. Method includes dust leaching at elevated temperature with transferring of copper and iron into solution, separation of solution from insoluble residue, separation of copper and iron. Than it is implemented evaporation of solution, containing basic quantity of copper, blue copperas crystallisation, separation of blue copperas crystals from growth solution and extraction from growth solution of residual quantity of copper. At that solution evaporation is implemented till providing of its density 1.30-1.36 g/cm3. Separation of copper and iron is implemented during the process of blue copperas crystallisation. Received blue copperas crystals are dissolved in sulfuric solution till providing of sulfuric acid concentration 100-250 g/l. Formed solution of blue copperas is exposed to basic electro- extraction with receiving of cathode copper and gate-type electrolyte. Extraction of copper residual quantity from growth solution is implemented by additional electro- extraction. Copper extraction degree from dust into solution at leaching is defined by content of copper in dust in oxidised form and reach 99.4%. Total copper extraction into cathodic metal is 89.4-95.2%.
EFFECT: receiving of qualitative cathode copper of grades MOOK, MOK, M1K, and also copper sponge at outlet by current on basic electro- extraction till 93,3% and at additional - till 74,6%.
10 cl, 4 ex
SUBSTANCE: invention can be used for production of high-purity silicon dioxide within integrated processing of magnesium-chrome crude ore that is mixed serpentinite, chromite, pyroxene and other minerals. Method of integrated processing of magnesium-chrome crude ore includes as follows. Crude ore is decomposed by solution of mineral acids. Produced suspension is filtered, and insoluble residue is processed. Filtrate neutralisation is accompanied with sedimentation of contained metal hydroxides with washing and drying of produced end-products. Processing of insoluble residue includes annealing at temperature 350-600°C, following dissolution in caustic soda to residual alkalinity 40-60 g/l NaOH, filtering of prepared suspension, washing of residue that is chrome ore concentrate and sedimentation of silicon dioxide from produced filtrate with solution of hydrochloric acid to residual acidity 2-15 g/l HCl.
EFFECT: higher separation integrity of silica component with simultaneous integrated extraction of other components of crude ore that provides extended application of base mixtures.
6 tbl, 2 ex
SUBSTANCE: invention concerns industrial sanitation and environmental protection field, at usage in manufacturing and in domestic conditions of metallic mercury, its containing devices and facilities, and also of amalgams, and is intended for neutralisation of mercury at its ingress both on surfaces of different materials and into volumes (material, brick, concrete and so forth). Neutralisation technique of metallic mercury by immobilisation includes its oxidation by means of treatment by water solution of hydrogen peroxide. At that additionally to oxidation it is implemented mercury deposition by means of simultaneous or successive treatment by water solution of reagent, transferring metallic mercury into insoluble or sparingly soluble in water compound of natural or anthropogenic composition. In the capacity of reagent there are used water-soluble compounds of alkaline or alkaline-earth metals for instance, sulphates, phosphates or carbonates.
EFFECT: effectiveness increase of process at excluding of mercury - organic compounds formation.
5 cl, 5 ex
SUBSTANCE: method includes leaching of material with water solution of chemical reagent and successive treatment of produced pulp for extraction of germanium and zinc. At that leaching is carried out with mechanical, grinding and disintegrating effect, using as solution chemical reagent of solution, containing oxidant at amount from 1.8 to 2.5 kg per 1 kg of germanium contained in source material and hydroxide of alkali metal at amount maintaining medium pH from 12 to 14 at ratio of solid and liquid phases 1:(3-8). Germanium is sorption settled out of produced pulp by means of transmission of pulp through ion exchanging resin; alkali at amount facilitating 13.5-14 pH of medium and water at amount facilitating ratio of solid and liquid phases 1:(5-8) are added to pulp. Product received after sorption sedimentation of germanium is treated in autoclave at temperature of 120-250°C and pressure of 6-40 atm. Then liquid phase is separated out of which zinc is extracted while germanium is eluated out of ion exchanging resin. Germanium is extracted out of produced eluate.
EFFECT: increased degree of germanium and zinc extraction.
4 cl, 2 ex
SUBSTANCE: invention refers to extraction and concentration of thorium out of process waste of loparit concentrates treatment - spent melt of saline sprinkler filter (SSF) of loparit concentrate chlorination process. The method includes preparation of suspension by means of discharge of spent melt of saline sprinkler filter (SSF) into water, incorporation of high molecular flocculant, of holding, filtering, separation of sediment, obtaining of chloride solution, and of treatment with steel scrap and metal magnesium. Prior to obtaining chloride solution the source suspension is heated to 60-90°C and treated with solution of sodium hydroxide to pH 1.5-2.0 and to 0.1-0.3% solution of high molecular flocculant at amount of 3-5% from the source volume of suspension; then suspension is held for 2-4 hrs. Chloride solution is received by means of filtration of spent suspension obtaining sediment of rare metals; chloride solution is then treated with steel scrap and metal magnesium; at that the solution is successively treated first with the steel scrap at amount of 3-5 mass fractions of iron per 1 fraction of iron ions (III) in chloride solution at 80-100°C for 1-3 hrs till achieving the value of pH in a pulp equal to 3.0-3.5. Then the pulp is separated from the non-reacted portion of the steel scrap and is treated with metal magnesium to pH 3.5-4.5, and further with 0.1-0.3% solution of high molecular flocculant taken at amount of 5-20% from the volume of chloride solution. Thus produced pulp is held without mixing for 1-4 hrs and filtered producing thorium containing sediment; the said sediment is washed at filter first with solution containing 1-5 g/dcm3 of sodium sulphite, then with water. Washed out sediment is repulped in solution of sodium hydroxide with concentration of 50-150g/dcm3 at a ratio of "Ж:Т"=3-5 at 60-90°C for 2-3 hrs, after what the pulp is filtered with separation of alkaline filtrate. Thorium containing sediment at the filter is washed with water, pressed at the filter and dried; the alkaline filtrate and process water are merged and mixed, then heated to 80-90°C, and treated with solution of sodium hydroxide to pH 11-13 with production of hydroxide pulp. Hydroxide pulp is filtered and then radioactive sediment is produced at the filter; it is washed out with water and transferred to a special wastes depositary, while filtrate is mixed with 10-20 volumes of shop flush water, heated to 80-90°C and again treated with solution of sodium hydroxide to pH 11-13. Obtained pulp is held and filtered thus producing sediment of rare metals and deactivated chloride solution which is discharged to drainage. Sediment of rare metals is unloaded from the filter, merged with sediment of rare metals extracted from the source suspension, dried, washed out and then transferred for preparation of charge for its further chlorination together with the loparit concentrate.
EFFECT: upgraded efficiency of thorium extraction and simultaneously solving problem of neutralisation and utilisation of process waste.
1 dwg, 1 ex
SUBSTANCE: invention refers to non-ferrous metallurgy and can be used for extraction of vanadium out of ashes which is waste produced by burning of sulphuric vanadium containing black oil in heat engines of heat and hydropower stations. The method consists in the following: source ashes are mixed with sodium carbonate and water at a weight ratio of 100:(10-60):(30-50), then produced mixture is held at temperature of 100-150°C, preferably 115-120°C, during 2 hours. Vanadium is leached out of produced self-diffusing cake with water at temperature of 95-100° and a ratio of liquid: solid = (1.5-3):1.
EFFECT: avoiding of generating harmful gas exhausts at extraction of vanadium and implementation of available equipment.
1 tbl, 2 ex
SUBSTANCE: method for pile loosening by blasting in heap leaching (HP) of ores is used to intensify the HP process due to performing drilling-and-blasting works. The method for pile loosening by blasting in heap leaching of ores, whereby a pad is formed by protective drainage 14 and damp-proof layers 15 made of polymeric film, consists in drilling boreholes 2, placing low-density explosive charges into the boreholes 2 and blasting of said charges. The boreholes 2 are drilled to the depth of the protective and drainage layer 14, charges 9 and 12 are distributedly disposed in the boreholes 2. Pieces 13 and 11 of an expanded material, e.g., foamed polystyrene, are placed respectively in the lower part of the borehole and between the charges. The charges are blasted with time delaying beginning from the top charge 9 to the bottom one 12.
EFFECT: increase in the efficiency of ore loosening; prevention of damage of the anti-seepage polymeric film membrane and of penetration of the toxic solution into ground waters.
FIELD: technological processes; metallurgy.
SUBSTANCE: method for cuvette-heap leaching of metals is related to hydraulic metallurgy and may be used in leaching of non-ferrous, rare and precious metals ores. Method includes treatment of mineral mass with solution of leaching agent and metal extraction. Treatment of mineral mass with solution of leaching agent and metal extraction is carried out in two stages. Previously mineral mass is placed in cuvettes with hydraulically insulated walls and bottom. Then solution of initial reagent is introduced, and local portion activation of produced pulp is carried out with provision of secondary reagents. After activation pulp is exposed to fractioning with extraction of sludge-clay and sand fractions. Sand fraction is dehydrated. Productive solution and sludge-clay fraction produced as a result are exposed to sorption or electric sorption leaching. Stacks are formed from sand fraction, and material is exposed to heap leaching. Liquid phase that remained after leaching of sand and sludge-clay fraction is additionally strengthened and sent for heap leaching.
EFFECT: higher efficiency of process.
2 cl, 1 ex
FIELD: metallurgy, mining.
SUBSTANCE: method for gold extraction from cyanic pulp includes gold sorption by means of pulp directing to ion-exchange resin by backflow in cascade of appliances. At that sorption is implemented at the control of concentration of gold in pulp liquid phase of each appliance. At reduction of gold concentration till 0.9 mg/l it is implemented extraction of resin from appliance and its regeneration by solution of caustic soda and/or sodium chloride brine.
EFFECT: increasing of resin sorptive capacity and extraction increasing of solute gold.
2 cl, 2 tbl, 1 ex
FIELD: metallurgy, mining.
SUBSTANCE: method for gold extraction from cyanic pulp includes gold sorption by means of pulp directing to ion-exchange resin by backflow in cascade of appliances containing of sorption tower. At that sorption is implemented at the control of concentration of thiocyanate and cyanide in pulp liquid phase of each appliance. At achieving of thiocyanate and cyanide accumulated concentration more than 0.5 g/l into pulp it is introduced oxidant in number, which is necessary for receiving of gold concentration in liquid phase of pulp 0.05-008 mg/l.
EFFECT: oxidation and decomposition of thiocyanate and cyanide in liquid phase, encouraging increasing of gold extraction.
FIELD: metallurgy, mining.
SUBSTANCE: method for gold extraction from thrust sulphide ore includes biooxidation with receiving acid pulp and its preparation to sorption leaching of gold by means of neutralisation and by oxygen aeration. At that neutralisation is implemented simultaneously to oxygen aeration at keeping of its content in pulp not less than 10 mg/dm3.
EFFECT: decreasing of elemental sulfur in products of biooxidation before carbonitriding and reduction of materials consumption and duration of preparation for carbonitriding.
1 tbl, 1 ex
FIELD: processes for extracting gold from ores.
SUBSTANCE: method comprises steps of breaking ore, double-stage disintegration of it, sorting, gravitation and flotation con centration, sorption leaching, electrolytic extraction of gold and melting it. At cycles of primary and secondary disintegration of initial ore hydraulic sorting is performed for producing sand fraction of ore and drain. Then sand fraction is divided by flow for gravitation concentration and flow for secondary disintegration. Divided flow of sand fraction is fed for gravitation concentration in quantity determined according to given formula: γ gr.f. = (0.3 - 0.4)γ in.ore + (0.2 - 0.6)γ circ.load where γ gr.f - mass of sand fraction of disintegrated ore fed for gravitational concentration; γin.ore - mass of initial ore fed for primary disintegration; γ circ.load - mass of circulation load for secondary disintegration. Gravitational concentration of drain and divided flow of sand fraction are realized for producing separate gravitation concentrates and separate tails. Then gravitation concentrates of drain and divided flow of sand fraction are combined and after their combination they are divided by "gold head" concentrate and depleted gravitation concentrate. The last is subjected to intensified cyaniding for producing solid phase and gold- containing solution. Tails of gravitation concentration of drain of sorting are subjected to flotation and prepared flotation concentrate is combined with solid phase of intensified cyaniding to be subjected to sorption leaching and desorption for producing gold-containing solution. Then separate electrolytic deposition of gold from gold-containing solutions of intensified cyaniding and sorption leaching is performed for producing separate cathode deposits of gold. Produced " gold head" and cathode deposits of gold are subjected to calcining and melting for producing gold in ingots.
EFFECT: lowered losses, increased degree of gold extraction, reduced circulation load and therefore improved efficiency of gold extraction.
FIELD: leaching extraction of non-ferrous and precious metals from refractory ores by cyaniding process.
SUBSTANCE: method involves cyclical or continuous leaching of metal from ore-containing pulp; supersonic processing; collecting and processing pregnant solution; providing supersonic processing at cyclical leaching after first leaching process and at continuous leaching - before first leaching process by exposing to supersonic field having intensity of 1-70x104 W/m2 in hydrodynamic generator and simultaneously feeding air. Method allows efficiency of metal extraction process to be increased due to fundamental changing of supersonic process parameters, in particular, supersonic field intensity, increased concentration of solved and dispersed gaseous oxygen and products of acoustic-chemical reactions in pulp, and additional grinding of ore grain.
EFFECT: increased efficiency of process and reduced labor intensity due to the fact that generator functions in self-oscillating operational mode and does not need additional works, and simplified process.
FIELD: hydrometallurgy, in particular, extraction of gold from rebellious sulfide auriferous-arsenical ores.
SUBSTANCE: method involves providing crushing, grinding, flotation concentration of basic raw material; performing biological oxidation of concentrate; neutralizing products of biological oxidation; providing sorption cyaniding of neutralized products of biological oxidation and flotation tailings; regenerating sorbent; electrolyzing solutions of eluted gold from sorbent; providing calcination and melting of cathode sediments for producing of alloy gold ingots; providing flotation of ore, which is ground to 85-90% size of 0.074 mm size class, using discharge of thickeners and recycled water from tailings dump, which water being conditioned to residual concentration of cyanide of 0.1-0.2 mg/l. Concentrate is subjected to biological oxidation at temperature of 37-42 C in two stages at concentration of oxygen in pulp of at least 1-2 mg/l. Biological oxidation products are neutralized to pH value of 4-6 without separation of solid from liquid in pulp using flotation tailings at first stage and milk of lime is neutralized at second stage with increase of pH value of pulp to 10.5-11. Neutralized biological oxidation products are subjected to sorption leveling at first stage with NaCN concentration of 400-500 mg/l, and at second stage sorption cyaniding of first stage tailings and all of flotation tailings at NaCN concentration of 200-300 mg/l is performed.
EFFECT: increased extent of extracting gold from rebellious sulfide auriferous-arsenical ores.
5 cl, 1 dwg, 1 tbl
FIELD: regeneration of free cyanide in waste technological solutions containing cyanides and heavy metals; non-ferrous metallurgical plants; gold mining and galvanic processes.
SUBSTANCE: proposed method consists in treatment of waste technological solutions by mineral acid under conditions excluding formation of gaseous hydrocyanic acid followed by separation of phases: solution of hydrocyanic acid and difficultly soluble compounds of elementary cyanides of metals by settling and/or filtration, leaching of clarified solution and re-use of solution of free cyanide thus obtained. Regeneration of free cyanide is carried out directly in solution being treated without conversion of hydrocyanic acid into gaseous phase.
EFFECT: repeated use of cyanide; reduced consumption of cyanide and fresh water; facilitated procedure; extraction of non-ferrous metals from solution in form of compact concentrate.
1 dwg, 2 ex
FIELD: hydrometallurgy of noble metals; stage of preparation of ores of tailings of gold extraction mill and beyond-balance ore of underground mining before heap leaching of gold.
SUBSTANCE: proposed method includes preparation of ore consisting in joint nudilizing of beyond-balance ore at content of gold no less than 0.5 g/t (50%) and old tailings (50%) at addition of cement in the amount of 2-2.4 kg/t.
EFFECT: enhanced efficiency of extraction of gold from technogenious wastes at low content of gold.
1 tbl, 6 ex
FIELD: hydrometallurgy of noble metals; leaching of gold from stacks.
SUBSTANCE: sodium cyanide solution is introduced at the moment when size of ore is lesser than 20 mm by sprinkling the ore escaping from hole of last crusher and sprinkling the minus material of screening of previous stages of crushing which is conditioned in size. Degree of extraction of gold from freshly crushed quartz-feldspar ore making use of ore "ripening" effect crushed to class of 10 mm and nodulized with sodium cyanide of piston-type sprinkling and oxygenation of circulating solutions is equal to 74% during 25 days.
EFFECT: enhanced efficiency of extraction of gold due to increased rate of dissolving.
6 tbl, 6 ex
FIELD: hydrometallurgy of precious metals; extraction of gold at heat leaching-out of gold-containing ores by cyanide solutions.
SUBSTANCE: proposed method includes additional dissolving of oxygen in cyanide solution in the amount of 33-38 mg/l for obtaining required degree of extraction of gold in product solutions equal to 80% during 10-15 days of leaching-out of crushed ore. Expenses for oxygen do not exceed 1.1.5 rubles/t of ore.
EFFECT: increased productivity; increased extraction of gold into product solutions.
1 tbl, 1 ex