CN1139704A - Method for extracting copper from ore - Google Patents
Method for extracting copper from ore Download PDFInfo
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- CN1139704A CN1139704A CN96103479A CN96103479A CN1139704A CN 1139704 A CN1139704 A CN 1139704A CN 96103479 A CN96103479 A CN 96103479A CN 96103479 A CN96103479 A CN 96103479A CN 1139704 A CN1139704 A CN 1139704A
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Abstract
The present invention relates to a method for extracting copper from copper oxide ore or from copper-containing floatation tailings of sulfide mine. Said method includes the following processes: breaking ore, mixing with acid, curing-leaching and electrolytic treatment. The broken ores or floatation tailings are mixed with acid, water and oxidant, then leached by using acid solution (electrolytic residual solution), and then the cathode copper and sponge copper can be obtained by using electrolytic process, and the electrolytic residual solution can be returned and used as leaching solution. Its technological process is greatly simplified. The investment, energy consumption, water consumption and environmental pollution also are greatly reduced.
Description
The present invention relates to the extracting method of metal, more specifically say so and extract the method for copper from copper oxide ore or from sulphide ores cupric flotation tailings.
The copper mineral that nature exists is divided into oxidized ore and sulphide ores two big classes.For the oxidized ore processing of (comprising the flotation tailings that copper exists with oxidized ore), the current Wet-process metallurgy method that generally adopts.As if in recent years, the copper hydrometallurgy stays cool, and do not have outstanding especially variation in the immediate future, but some also can come out gradually with the improvement of technology.Its old process is by ore reduction, levigate, agitation leach, and solid-liquid separation, solvent extraction, six big operations such as galvanic deposit (system cathode copper) and the disposal of mine tailing slurry are formed.Be that copper enters solution from ore, make " pure " copper solutions, produce metallic copper by electrolytic deposition then through solvent extraction.This method changes solution in order to make copper " fully " over to by ore, must make ore reduction, levigate copper mineral enough contact probabilities be arranged with leaching agent, carries out fully thereby make to leach to react.Yet the levigate wet method metallurgical process of giving of ore has been brought following consequence: (1) flow process energy consumption height: ore grinding is one of main power consumption operation of copper mine hydrometallurgy, and its power consumption accounts for 1/3～1/2 of whole flow process (routine); 2) solid-liquid separation difficulty:, after the ore agitation leach, must carry out strict solid-liquid separation, but ore grinds to such an extent that thin more solid-liquid separation is difficult more for purification enrichment copper from leach liquor; (3) water consumption is big, has aggravated environmental hazard: to topsoil, the pollution of water surrounding is the intrinsic deficiency of hydrometallurgy as pyrometallurgy.For the old process based on agitation leach, the water displacement of handling one ton of ore reaches 3～5m
3Or more, disposing huge like this mine tailing slurry is the heavy burden of hydrometallurgy process.In addition, by organic phase (solvent and extraction agent) toxicity and the fire hazard that solvent extraction brought, also be the noticeable deficiency of current copper hydrometallurgy (" Hydroxyoxime and Copper hydrometallurgy ", CRC Press Inc.London, 1993) .1977 United States Patent (USP) (US NO.4,017,309) a kind of " thin layer lixiviation process " disclosed, it is to leach a coarse grain ore through fragmentation with concentrated acid, as if ore does not need further levigate, solved above-mentioned three problems that caused by grinde ore.But this method can not leach in the oxidized ore the non-solubility in acid copper mineral that exists usually, and its leach liquor must carry out solvent extraction, makes the copper purification enrichment, just can make qualified metallic copper.U.S. Pat 5356457 discloses a kind of method of solvent extraction legal system copper.As everyone knows, solvent extraction not only exists the toxic environmental problem of organic phase, and be to require high (the necessary fully clarification of feed liquid in the copper hydrometallurgy, solids content＜25ppm), operation difficult (characteristic that is separated of extraction process, organic phase loss etc. depend on feed liquid characteristic and operating environment thereof strongly), consume the operation sequence of big (extraction agent costliness, the cost of extraction cells operation accounts for more than 1/3 of total cost greatly).
The objective of the invention is to provide the method for extracting copper from ore that a kind of flow process is short, energy consumption is low, water is few, environmental pollution is little.
Technical scheme of the present invention is as follows: the ore or the flotation tailings that are crushed to certain particle size mix in solid amalgamator (being called acid mixer) with acid solution and oxygenant, through heat or the normal temperature slaking after, decopper(ing) raffinate (being leachate) leaching ore bed is separated in electricity consumption, leachate not only comes out the component that has leached in ore (or mine tailing) the concentrated acid curing process, but also will be remaining in the useful component leaching on depths, capillary-size pore and the newborn fissure-plane and coming out.This leaching process is similar to conventional dump leaching operation, but it connects the multistage counter current mode and carries out.Like this, just become the stable operating system of a serialization from ore reduction to leaching, rather than the periodical operation as conventional dump leaching.
The blue-green solution that leaching effluent liquid (being leach liquor) is a kind of copper content height, solids content is low.For oxidized ore, the content of various impurity is all very low in the leach liquor.This leach liquor can directly enter electrowinning process.For degree of oxidation not high ore or flotation tailings, when making oxygenant with Manganse Dioxide or high ferro, the content of iron is higher in the leach liquor, needs after the siderotil precipitator method are removed de-iron the electrowinning process of being allowed for access.Electrowinning process is made up of galvanic deposit and electrolysis decopper(ing) two portions.The former product is that cathode copper (account for copper products total amount 50%～90%) latter's product is copper sponge (work in-process, account for 10%-50%) raffinate (be residual electrolyte, copper content is lower than 0.5g/L) behind the electrolysis decopper(ing) all or most of (75%-95%) return the leaching operation.Whole factory is a water circulation system, does not arrange or few row (0.15～0.2m
3/ t) processing wastewater, refuse outside the discharge factory of factory only is or mainly is the leached mud of water ratio about 20%, but its backfill stope or dried banking up, cinder yard rainwater effluent liquid major part (looking quantity of precipitation) can be returned factory and make water of productive use, save the necessary tailing pond of current old process, avoided huge mine tailing slurry to dispose basically.
Fig. 1 is a process flow diagram of the present invention.As seen from Figure 1, processing step of the present invention is as follows:
(1) broken (flotation tailing is without this operation): ore reduction to 5～15mm.
(2) leach (namely mixing acid, slaking and leaching): ore (or flotation tailing) mixes and stirs (granulation) with acid, water and oxidant after broken, used acid is generally the concentrated sulfuric acid (special circumstances can be used hydrochloric acid), oxidant is peroxosulphuric, manganese dioxide or trivalent iron salt, the consumption of acid, water and oxidant is different because of the ore deposit, the acid consumption is generally 15～200kg/t ore deposit, water consumption is generally 10～100kg/t ore deposit, and the oxidant consumption is generally 0.1～20kg/t ore deposit; Mix sour granulation material and carry out slaking: but normal temperature was banked up 5～10 days or was heated to 70～95 ℃ of maintenance 1-2h. Material carries out the multistage counter current leaching with leachate (by residual electrolyte, water and oxidant preparation, the i.e. modulation of residual electrolyte) after the slaking, industrially generally can adopt 3～8 sections, and the leaching cycle is 8～45 days, and leaching intensity is 0.30～1.5m3/ t ore deposit. section; The parameter of residual electrolyte modulation determines general pH=1.3～3.5 by the pH value of leaching efflux.
(3) siderotil deironing: for the not high leaching material of some degree of oxidation (ore or mine tailing), when making oxidant with manganese dioxide or high ferro, the leachate iron content higher (＞5g/L), must purify through the deironing of the siderotil precipitation method and remove again electrowinning process. The process conditions of siderotil precipitation method deironing are:
Precipitation agent is 5%～10% milk of lime (or adding 0.2%～1.0% yellow soda ash);
Temperature is 75～90 ℃;
Time is 1～5 hour;
Precipitating whole pH value is 1.4～3.5.
For the direct electrodeposition of general oxidized ore leach liquor, there is not this operation.
(4) electrolysis: for the material of copper grade＞1.5%, leach liquor copper concentration 〉=30g/L generally can directly carry out the insoluble anode electrolysis and make cathode copper, i.e. galvanic deposit.When electrolytic solution copper concentration is reduced to 5～8g/L, change groove and carry out the second one-step electrolysis decopper(ing) (under this condition the foreign matter content copper sponge suitable beyond the deoxygenation) with the galvanic deposit product, reduce to≤0.5g/L until electrolytic solution copper concentration.This residual electrolyte returns and leaches operation preparation leachate.The processing condition of two one-step electrolysis are:
Anode: lead alloy (Ag1%, Sb3～4%);
Anodes centre's distance: 10 ± 1cm;
Negative electrode: stainless steel or copper coin;
Temperature: 30～55 ℃;
Bath voltage: 2～2.8V;
Current density: 80～300A/m
2
The return rate that residual electrolyte returns leaching is 75%～95%, because of the physical properties and the leaching characteristic that leach material different.
(5), for the purpose of safe, should be leach liquor the controlled filter operation is set if consider contingent accident or carelessness in the industrial production.Its equipment can adopt double-deck filter bed (coal-river sand), and the bed linear velocity is 15～20m/h, bed pressure drop≤25kPa.
The present invention has following advantage:
1. compare with the common process flow process, flow process of the present invention has been saved grinde ore, solid-liquid separation and solvent extraction step, has also simplified the disposal of mine tailing slurry simultaneously, and flow process is simplified greatly.
2. the capital investment of flow process of the present invention and operational cost are about about half of routine (agitation leach) flow process;
3. the power consumption of flow process of the present invention is about 50%～60% of old process;
4. the water consumption of flow process of the present invention is about 1/10～1/20 of old process;
5. the conventional lixiviation process of the sour amount ratio of flow process of the present invention lacks 1.0～1.3t/tCu;
6. leaching method of the present invention has whole advantages of conventional dump leaching, but has fundamentally overcome the intrinsic deficiency of dump leaching method, and extraction yield height, adaptability are good, with regard to simple leaching index, also are better than (being equivalent at least) conventional agitation leach method;
7. owing to realized recycling of process flow fluid (residual electrolyte), flow process of the present invention can be accomplished few row (0.15～0.2m
3/ t ore deposit) or not effluent, the leached mud of arranging can be done heap or backfill stope, has outstanding environmental benefit.
In sum, no matter be the complex art economic target of flow process, or the individual event specific targets of operation, the present invention is greatly improved than conventional agitation leach method, be one simple to operate, adaptability good, the extracting method of the copper that benefit is outstanding.
Embodiment 1:
(1) be grade that the oxidized ore of the strong kaolinization of 13.2% (oxidation ratio～98%) is crushed to-5mm.
(2) get breaking ores (wet meter water ratio 26.4%, doing meter 35.8%) 2.5kg mixes (mixing acid) with the 0.38kg vitriol oil, 45mL water in acid mixer, normal temperature is placed 8 days (slaking), get leach liquor (copper content Cu=65.4g/L) with leachate (residual electrolyte accounts for 80%, water account for 20%, the about 75g/L of sulfuric acid concentration) leaching; Copper leaching rate 97.3%.
(3) leach liquor directly carries out conventional galvanic deposit and electrolysis decopper(ing), and condition is:
Anode: lead alloy (Ag1%, Sb3～4%);
Anodes centre's distance: 10.1cm;
Negative electrode: stainless steel plate;
Temperature: 35 ℃;
Bath voltage: 2.5V;
Current density: galvanic deposit 280～300A/m
2
Electrolysis decopper(ing) 85～100A/m
3
Cathode copper (plate) quality meets Ministry of Metallurgical Industry's ministerial standard (seeing attached list 1); The copper sponge productive rate accounts for 10%～90% of total copper amount, and the content of copper sponge is greater than 84%.
Embodiment 2:
(1) copper grade 1.58% (oxidation ratio～75%) silt content is reached 40% oxidized ore, be crushed to-7mm.
(2) getting broken back sample ore (doing meter water ratio 2.1%) 5.0kg mixes in acid mixer with the 0.40kg vitriol oil, 260mL water and oxygenant peroxosulphuric 60g, normal temperature slaking 10 days, (residual electrolyte accounts for 90%, water accounts for 10%, peroxosulphuric oxygenant 5g/L with leachate, the about 40g/L of sulfuric acid concentration) leaching gets leach liquor (copper content Cu=35g/L), copper leaching rate 91.3% (the agitation leach method is 75.1%).
(3) leach liquor two one-step electrolysis are with embodiment 1, and the copper sponge productive rate accounts for 60%～75% of total copper amount, product purity qualified (seeing attached list 1).
Embodiment 3:
(1) copper grade 1.36% (oxidation ratio～82%) silt content is reached 50% oxidized ore, be crushed to-7mm.
(2) getting broken back sample ore (doing meter water ratio 4.1%) 5.0kg mixes in acid mixer with the 0.50kg vitriol oil, 130mL water, normal temperature slaking 10 days, (residual electrolyte accounts for 90%, water accounts for 10%, add ferric sulphate, (Fe+3) concentration reaches about 25g/L to make high ferro with leachate, the about 40g/L of sulfuric acid concentration) leaching gets leach liquor (copper content Cu=35g/L, Fe～34g/L), copper leaching rate 88.3% (the agitation leach method is 75.1%).
(3) leach liquor purifies through the deironing of the siderotil precipitator method and removes electrowinning process again.The processing condition of siderotil precipitator method deironing are:
Precipitation agent is 5% milk of lime;
Temperature is 90 ℃;
Time is 4.5 hours;
Precipitating whole pH is 2.0.
(4) leach liquor two one-step electrolysis are with embodiment 1, and the copper sponge productive rate accounts for 60%～75% of total copper amount, product purity qualified (seeing attached list 1).
Embodiment 4;
(1) copper grade 0.98% (solubility in acid copper about 20%) powdery flotation tailings (doing meter water ratio 5.6%) 0.50kg is mixed in acid mixer with the 0.35kg vitriol oil, 50mL water and 7.5g Manganse Dioxide, 95 ℃ of slaking 2h, (residual electrolyte accounts for 95%, water accounts for 5% with leachate, the about 35g/L of sulfuric acid concentration) leaching gets leach liquor (copper content Cu=19g/L, Fe～15g/L), leaching yield 89.4%.
(2) leach liquor purifies through the deironing of the siderotil precipitator method and removes electrowinning process again.The processing condition of siderotil precipitator method deironing are:
Precipitation agent is 5% milk of lime;
Temperature is 80 ℃;
Time is 3 hours;
Precipitating whole pH is 1.8.
(3) deironing leach liquor two one-step electrolysis are with embodiment 1, and the copper sponge productive rate accounts for 40%～50% of total copper amount, and product purity sees attached list 1.
Subordinate list 1 copper products major impurity is formed
| Project | Content (pmm) | |||||||||
| ????Fe | ????S | ????Bi | ????Sb | ????As | ????Pb | ????P | ????Sn | ????Ni | ????Zn | |
| Oxygen free copper standard promulgated by the ministries or commissions of the Central Government | ????50 | ????50 | ????20 | ????20 | ????20 | ????50 | ????30 | ????20 | ????20 | ????30 |
| Embodiment 1 copper products | ????15 | ????40 | ????18 | ????17 | ????27 | ????15 | ????30 | ????10 | ????17 | ????20 |
| Embodiment 2 copper products | ??＜10 | ??＜10 | ????30 | ??＜10 | ????18 | ??＜10 | ??＜10 | ??＜10 | ??＜10 | ??＜10 |
| Embodiment 3 copper products | ????18 | ??＜10 | ????30 | ????15 | ????18 | ??＜10 | ??＜10 | ??＜10 | ??＜10 | ??＜10 |
| Embodiment 4 copper products | ??＜10 | ????18 | ??＜10 | ??＜10 | ????33 | ??＜10 | ????20 | ??＜10 | ??＜10 | ??＜10 |
Claims (7)
1. method of extracting copper from ore is characterized in that this method undertaken by following operation:
(1) fragmentation: ore reduction to 5～15mm (flotation tailings does not have this operation);
(2) mix acid: broken ore or flotation tailings mix and stir with acid, water and oxygenant;
(3) slaking-leaching: mix material after the acid and banked up at normal temperatures 5～10 days or heated to 70～95 ℃ and kept 1～2 hour, obtain leach liquor with the leachate leaching then;
(4) electrolysis: first section galvanic deposit obtains cathode copper, and second section electrolysis decopper(ing) obtains copper sponge.
2. extraction copper method as claimed in claim 1, the acid that it is characterized in that mixing sour usefulness is the vitriol oil; Oxygenant is peroxosulphuric, Manganse Dioxide or trivalent iron salt.
3. extraction copper method as claimed in claim 1 is characterized in that leaching is operating as 3～8 sections adverse current leachings, and the leaching cycle is 8～45 days, and leaching intensity is 0.3～1.5m
3/ t ore deposit. section.
4. extraction copper method as claimed in claim 1 it is characterized in that when this technology started, leachate was a sulphuric acid soln, and when technology was moved continuously, leachate was mainly residual electrolyte; It is formed mainly is acid and oxygenant (acid and the oxygenant used with mixing acid are identical).
5. extraction copper method as claimed in claim 1 is characterized in that residual electrolyte returns the preparation leachate, and the ratio of returning is: 75%～95%.
6. extraction copper method as claimed in claim 1 when it is characterized in that the concentration＞5g/L when iron in the leach liquor, carries out the siderotil precipitation process to this leach liquor, and its processing condition are:
Precipitation agent is 5%～10% milk of lime (or adding 0.2%～1.0% yellow soda ash);
75～90 ℃ of precipitation temperatures;
1～5 hour time;
Final pH control 1.4～3.5.
7. extraction copper method as claimed in claim 1 is characterized in that electrolytic processing condition are:
Anode: lead alloy (Ag1%, Sb3～4%);
Anodes centre's distance: 10 ± 1cm;
Negative electrode: stainless steel plate or copper coin;
Temperature: 30～55 ℃;
Bath voltage: 2～2.8V;
Current density: 80～300A/m
2
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN96103479A CN1049693C (en) | 1996-03-22 | 1996-03-22 | Method for extracting copper from ore |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN96103479A CN1049693C (en) | 1996-03-22 | 1996-03-22 | Method for extracting copper from ore |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1139704A true CN1139704A (en) | 1997-01-08 |
| CN1049693C CN1049693C (en) | 2000-02-23 |
Family
ID=5118090
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN96103479A Expired - Fee Related CN1049693C (en) | 1996-03-22 | 1996-03-22 | Method for extracting copper from ore |
Country Status (1)
| Country | Link |
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| CN (1) | CN1049693C (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101736152B (en) * | 2008-11-24 | 2011-08-17 | 北京有色金属研究总院 | Acid washed ore leaching process for low-grade copper oxide ores with high mud content |
| CN102363890A (en) * | 2011-10-26 | 2012-02-29 | 广州有色金属研究院 | Method for recovering metal copper in waste circuit board |
| CN105274331A (en) * | 2014-07-18 | 2016-01-27 | 沈阳有色金属研究院 | Method for recycling copper through heating and leaching low-grade copper tailings by means of air energy |
| CN106757175A (en) * | 2016-11-28 | 2017-05-31 | 重庆新川塔实业股份有限公司 | Electrolysis ore electrolytic cell |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CA1086505A (en) * | 1977-05-13 | 1980-09-30 | Ashok D. Dalvi | Roast-leach copper recovery |
| CN1110326A (en) * | 1994-04-11 | 1995-10-18 | 宁蒗彝族自治县乡镇企业局溶浸炼铜厂 | New process for extracting copper by leaching-electrode position |
-
1996
- 1996-03-22 CN CN96103479A patent/CN1049693C/en not_active Expired - Fee Related
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101736152B (en) * | 2008-11-24 | 2011-08-17 | 北京有色金属研究总院 | Acid washed ore leaching process for low-grade copper oxide ores with high mud content |
| CN102363890A (en) * | 2011-10-26 | 2012-02-29 | 广州有色金属研究院 | Method for recovering metal copper in waste circuit board |
| CN105274331A (en) * | 2014-07-18 | 2016-01-27 | 沈阳有色金属研究院 | Method for recycling copper through heating and leaching low-grade copper tailings by means of air energy |
| CN105274331B (en) * | 2014-07-18 | 2018-04-20 | 沈阳有色金属研究院 | It is a kind of that the method for leaching low-grade copper mining tailing copper can be heated using air |
| CN106757175A (en) * | 2016-11-28 | 2017-05-31 | 重庆新川塔实业股份有限公司 | Electrolysis ore electrolytic cell |
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| Publication number | Publication date |
|---|---|
| CN1049693C (en) | 2000-02-23 |
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