In China, molybdenum resources are extremely rich, accounting for about 37% of the world's total, mainly concentrated in Henan, Shaanxi, Liaoning, Hebei and other places, and most of them are derived from porphyry copper- molybdenum ore. At present, with the development of economic construction, the demand for copper and molybdenum is increasing. However, copper and molybdenum resources are rich in ore, rich in ore, serious associated with others, many other useful components, fine inlaid grain size, molybdenite and Copper sulphide ore is similar in floatability, which makes it difficult to separate copper and molybdenum. Therefore, the research and application of copper-molybdenum separation technology is particularly important. Hand-Push Crack Sealing Machine Asphalt Crack Filler Machine,Hand-Push Crack Sealing Machine,Hand-Push Road Crack Sealing Machine,Hand-Pushing Type Crack Sealing Machine Shandong Storike Engineering Machinery Co., Ltd. , https://www.storikemachinery.com
1. Copper-molybdenum flotation separation technology
At present, the use of flotation to treat copper-molybdenum ore is more common, the process technology is mature, and the indicators are better. In principle, the flotation method of copper-molybdenum ore has three kinds of flotation, preferential flotation, and other flotation. Most of the production is mixed flotation, but sometimes it is preferred to float or float.
2. Mixed flotation technology of copper and molybdenum
Most copper-molybdenum ore adopts mixed flotation-copper-molybdenum separation process because molybdenite and chalcopyrite are similar in floatability and associated with serious process. The process cost is low and the process is simple.
3. Mixed flotation
In general, flotation collector xanthates selected (butyl xanthate), an auxiliary collector hydrocarbon oil (kerosene), as blowing agents include pine oil, lime and waterglass adjustment agent . Ye Lijia conducted a test on a low-grade copper-molybdenum mine in Anhui Province. He found that kerosene was used as a collector and BK301C was used as an auxiliary collector for copper-molybdenum mixing. The recovery rate of copper and molybdenum was 93. 01% and 73.2%, the effect is much better than other auxiliary collectors.
4. Copper-molybdenum separation pretreatment
Under normal circumstances, the copper-molybdenum separation process has two schemes: molybdenum-free float copper and copper-stop float molybdenum. In view of the fact that molybdenum ore is more easily floated, most of them adopt the method of suppressing copper and molybdenum. However, when separating high-copper and low-molybdenum ore, the process of suppressing molybdenum floatation should be considered, because copper inhibition will result in high pharmaceutical costs. In addition, molybdenum ore has good floatability, and inorganic or organic small molecule inhibitors are not easy to function, which allows the use of some polymer inhibitors such as dextrin, starch, humic acid, tannic acid, etc.
Copper-molybdenum separation mainly includes pre-treatment before separation, inhibition of copper minerals during separation, and re-enrichment after separation of copper and molybdenum. The main methods of preprocessing are as follows:
1) Concentrated mixed concentrate. Mainly remove the residual agent and foaming agent in the flotation copper-molybdenum mixed concentrate. Liu Zilong and others intensified the application of this pretreatment in the second phase reconstruction of the Wunuge Tushan copper-molybdenum ore dressing plant. The ceramic filter was used as the concentration equipment after the copper-molybdenum mixed flotation, which solved the current situation that the molybdenum ore was difficult to separate and obtained the grade. 57. 75% of molybdenum concentrate. The sulphide concentrate is increased by 0.36%, the recovery rate is increased by 11.14%, and the sodium sulfide consumption is reduced by 32. 17%. .
2) heating method. Heating the mixed concentrate can decompose the collector on the mineral surface, destroy the hydrophobic membrane, and evaporate the foaming agent in the slurry. Thus, the surface of the copper mineral is oxidized, the floatability is lowered, and the effect is suppressed, and the effect on the molybdenite is minimal, thereby achieving separation. At present, the main heating methods include heaters, roasting, and steam blowing. It is confirmed that about 40% of the world's copper and molybdenum plants are treated by heat treatment, which not only reduces the amount of sodium sulfide, but also significantly improves the beneficiation index.
3) Add the medicine. Primarily oxidizing agents such as peroxide, ozone, chlorine, potassium permanganate, oxygen, etc., in order to oxidize the surface thereof and the hydrophilic copper, collector adhered oxidized and decomposed. When the pH is 10 to 11, O2 in the slurry oxidizes the chalcopyrite to S2O32- and inhibits it. Natarajan et al. used electrochemical tests to verify that ozone effectively oxidizes and decomposes chalcopyrite surface collectors and is more effective than oxygen.
Therefore, by controlling the slurry conditions such as oxygen supply, pH adjustment, etc., it can inhibit the realization of copper-suppressing molybdenum in chalcopyrite, but it should be noted that the amount of oxidizing agent should not be too much. If it is excessive, it will affect the next copper suppression. The molybdenum unit has a strong reducing effect of sodium sulfide.
5. Copper and molybdenum separation inhibition
An important aspect of the copper-molybdenum separation process after pretreatment is the selection of flotation inhibitors. Commonly used inhibitors can be divided into inorganic and organic substances, inorganic substances are mainly Knox, cyanide, sodium sulfide, etc., organic substances are mainly thioglycolate, etc., either alone or in combination.
1) Cyanide. Sodium cyanide complex comprising zinc, iron and sodium cyanide. Mainly for copper, iron sulfide ore suppressed, and its object is to destroy xanthate, cyanide stable complex formation, is very effective, highly efficient small amount, in Jinduicheng processing plant production applications, the molybdenum fine The 5% molybdenum concentrate is obtained by adding sodium cyanide from 0. 05 to 0. 06 kg / t. However, it is highly toxic, especially in the case of mines containing gold and silver . The application of this method in the plant is gradually reduced.
2) Sodium sulfide. Mainly sodium hydrosulfide, sodium sulfide, ammonium sulfide, etc., the research confirmed that the main inhibitory effect is the SH- formed by the hydrolysis of sulfide. The most used in actual production are sodium sulfide and sodium hydrosulfide. For example, Dexing Copper Mine uses Na2S for copper-suppressing molybdenum. The beneficiation index is good, but sodium sulfide is easily oxidized and ineffective, up to 80-100. Kg / t, the proportion of pharmaceutical fees is quite high, accounting for 85% of the cost of molybdenum.
Domestically, the Beijing Nonferrous Metallurgy Design and Research Institute also selected the Dexing Copper Mine to conduct a nitrogen-filled industrial test, which reduced the amount of sodium sulfide by 60.55%. It is worth noting that sodium sulfide and sodium cyanide can inhibit chalcopyrite well, but the inhibition effect on a large amount of chalcopyrite and secondary chalcopyrite is quite poor.
3) Mercaptoacetate. In particular, thioglycolic acid has good inhibition effect, low dosage, low pollution and high selectivity. Wan Shenghui and other thioglycolic acid were synthesized by sodium sulfide method, and industrial experiments were carried out in Dexing Copper Mine. Good inhibitor effect was obtained. The obtained molybdenum concentrate grade was 51.53%, and the molybdenum concentrate recovery rate was 79. 89%。 The copper content is only 0.32%.
4) New inhibitors. Jiangyu Ren et al DPS synthesized novel inhibitors, which may inhibit tests showed chalcopyrite, galena, but little effect on the molybdenite, in an amount of 1/5 sodium sulfide and sodium acetate mercapto-1/10, The stability is good, the synthetic route is simple, and the raw material price is low. Yuan Zengwei studied the new inhibitor CM1. Compared with thioglycolic acid, the inhibitory effect of CM1 was more obvious, the dosage was less (20 g / L reduction), the action time was fast, and the lead ore was also inhibited.
6. Copper and molybdenum separation and selection
After the separation of copper and molybdenum, the next step of molybdenum selection and copper selection is carried out. The molybdenum is generally selected six times to meet the smelting requirements. Sometimes some molybdenum in the flotation concentrate will not be completely dissociated, and the regrind process is inevitable. Zhang Hengwang will improve the process of the Xiaosigou copper-molybdenum ore and increase the regrind process before molybdenum selection. The final concentrate grade of molybdenum reaches 46.49. % recovery of 92.26%, than no further grinding were increased 0.5% and 3.97%.
Copper selection is relatively simple, generally a selection can be, but the technology of asynchronous mixed flotation is worth mentioning, that is, flotation of float float copper, and enhanced flotation of difficult copper (addition of xanthate) Mix two-step copper concentrate and re-select it.
7. New technology and equipment for copper and molybdenum separation
1) Application of Flotation Column One of the advantages of flotation column is that it has good recovery effect on difficult mineralized fine particles and fine mud content. The characteristics of copper-molybdenum ore are fine grain size, low ore grade, serious associated with the need for fine The grinding grain size, combined with the excessive pulverization phenomenon, makes sorting difficult. Therefore, a flotation column can be used instead of a partial flotation machine to enhance the sorting effect. At present, there are many flotation columns used, such as cyclone-static microbubble flotation column, Jameson flotation column, SFC type filling type static flotation column, etc. Ma Zilong et al. used a rotation in the reconstruction of a copper-molybdenum plant in Xinjiang. flow - static microbubble flotation column flotation as copper-molybdenum, copper-molybdenum separation, selected from the main equipment of molybdenum, copper molybdenum, and copper-molybdenum separation scavenger flotation machines the flotation, the flotation system jointly constituting the machine column The recovery index is 50.59% of the molybdenum concentrate grade, 55.96% of the molybdenum recovery, 21.39% of the copper concentrate grade, and the copper recovery rate of 91.57%.
2) Application of potential adjustment technology Flotation electrochemistry is also quite effective in the separation of copper and molybdenum. The sequential flotation of different sulfide ore is achieved by controlling the slurry potential. Chander et al. tested the use of externally controlled potential method for electrochemical flotation separation of molybdenite and chalcopyrite. Krishnaswamy et al. concluded that molybdenum ore is naturally floatable due to its poor electron-conducting ability, that is, the change in slurry potential. less effect, and flotation requirements are chalcopyrite oxidation slurry, whereby the slurry can be controlled by external pH and potential of the chalcopyrite is achieved inhibited under a reducing atmosphere, while still molybdenite flotation to achieve separation.
8. The copper-molybdenum flotation technique
For low-grade molybdenum copper ore, molybdenum concentrate grade and recovery while ensuring at the same time, also consider the comprehensive recovery of copper using flotation sometimes more appropriate.
Dai Xinyu et al. conducted a study on a copper-molybdenum deposit in Tibet. The copper-molybdenum ore has secondary secondary copper and high oxidation rate. The size of the chalcopyrite inlay is fine, and the phenomenon is encased by gangue. The molybdenite is embedded in the vein. between the fracture and rock particles, using a floating process priority molybdenum, copper molybdenum regrinding separated, floating tailings molybdenum recovery of copper, molybdenum mineral collectors + kerosene and diesel, copper-molybdenum separation DY08 inhibitors, copper collector OSN- The result of the selection is 55.66% of the molybdenum grade in the molybdenum concentrate, 0. 071% of the copper, the recovery rate is 88.58%, the copper grade in the copper concentrate is 21.84%, and the recovery rate is 75.93%. Save 10% less than hybrid flotation.
9. Copper and molybdenum flotation technology
In general, flotation and flotation require high alkalinity (lime) separation of copper and molybdenum, sulfur, lime inhibitory effect of molybdenum, molybdenum is not conducive to recovery. Such flotation can avoid such problems. Selective collectors are used, and no separation or use of lime is used to separate copper molybdenum from sulfur, which is beneficial to the next copper-molybdenum separation and molybdenum selection. Better indicators. Hu Zhenfeng used an equal flotation process in the research of a copper-molybdenum ore process. The mine has a low molybdenum grade and slightly more pyrite.
10. Copper and molybdenum metallurgy combined technology
For most porphyry copper-molybdenum deposits with molybdenum and copper symbiosis, flotation treatment can be used. However, in the treatment of certain refractory copper-molybdenum ore, it is possible to use a combination of metallurgy and metallurgy. For example, Utah Bingham Canyon copper molybdenum, molybdenum copper porphyry belongs, the main mineral molybdenite, chalcopyrite, talc, sericite large content, of the clay mineral and easy. 4%。 The traditional process is a mixed flotation, copper-free floating molybdenum, multiple molybdenum selection, reverse flotation talc, obtained molybdenum containing 52.3% concentrate, re-oxidation roasting, the recovery rate is only 49.4%.
11. Conclusion
Mixed flotation is applied to the separation of most copper-molybdenum ore. Sometimes it is worthwhile to consider flotation and flotation. The key point is that the grades of copper and molybdenum in the ore and the size of the inlay will affect the dosage and grinding. The other links, that is, the economic cost of mineral processing and the quality of mineral processing indicators.
Effective pretreatment and selection of inhibitors are the key links of copper-molybdenum mixing and re-separation. Concentration, heating and oxidation can effectively destroy and remove the agent, but it should not cause "secondary pollution" to affect the separation of copper and molybdenum. The inhibitory effects of ketones, cyanide, and sodium sulfide are good, but there are deficiencies in "toxicity" or excessive use. Thioglycolate is more promising, and the dosage is less efficient. The development of new pharmaceuticals and combination medications is still a worthwhile effort.