(2) Increase production, save expenditure, application branch-speed separation flotation process Because the process structure is reasonable, the utilization rate of the flotation machine is improved, and the production capacity of the original 48-slot 6A flotation machine is increased by 15%, which can save float every year. selection electricity 350,000 degrees, saving electricity 35,000 yuan, saving equipment maintenance costs 03,600 yuan, 09,900 yuan and laboratory water costs 05,900 yuan, the plant used to make the equipment and comprehensive recovery of pyrite to produce each year The sulfur concentrate with more than 40% sulfur contains 1.5 to 50,000 tons, which will increase the income of the mine by more than 300,000 yuan. The economic effect of the investment in the current year, the transformation in the current year, the recycling in the current year, and the benefit of the year was realized, and the profit margin of the output value reached a high level of 69.4%. Closed circuit test result product Yield(%) grade(%) Recovery rate(%) Zn As S Sn Zn As S Sn Zinc concentrate 11.24 48.47 0.14 31.61 0.068 86.15 1.54 27.38 0.57 Arsenic concentrate 6.6 3.79 13.1 22.14 0.23 3.95 84.85 11.26 1.15 Sulfur concentrate 24.65 1.8 0.39 30.01 0.19 7.04 9.43 57 3.55 Tailings 56.51 0.23 0.07 0.92 2.21 2.06 3.89 4.01 94.46 overflow 1 5.04 0.3 4.53 0.36 0.8 0.29 0.35 0.27 Feed mine 100 6.32 1.02 12.98 1.32 100 100 100 100 The high content of pyrrhotite is a major feature of the ore. It is of course advantageous to use magnetic separation to reduce the minerals and difficulty of separation of sulfide ore and save the chemical cost by 50-70%. Comparison table of harmful elements in sewage Production conditions Measurement result (mg/L) Mn CN - Pb ++ Cu ++ Zn ++ S = Cyanide 1185 3.32 32.9 5.16 14 17.8 Cyanide free 1100 0 21.09 4.67 9.49 9.15 Note: Mn - suspended matter Among the new separation inhibitors, it is also worth mentioning ammonium humate. Guangxi Institute of Metallurgy used ammonium humate and lime as inhibitors of galena to separate lead and copper mixed concentrate, which reduced the copper grade of lead concentrate from 2.66% to 1.15%, thus increasing the lead concentrate from the sixth grade to the third grade. Product, lead operation recovery rate of 95%, copper concentrate main grade 13%, copper recovery rate of 62%. The separation of copper and lead with ammonium humate has a great influence on the pH value of the slurry. Under different pH values, the floatability of copper, lead and zinc minerals is shown in the figure below. The experiment shows that ammonium humate has strong inhibitory effect on sphalerite and galena in strong alkaline (pH 13～14) medium, but weak inhibition on chalcopyrite, and this difference can be used for copper lead or Copper and zinc separation. Uic54 Rail Joint Bar,Uic Standard Fish Plates,Uic54 Fish Plate,Railway Uic60 Joint Bars Anyang Railway Equipment CO.,Ltd , https://www.ayrailwayat.com
4. Magnetic-floating joint process
Dachang Bureau of Mines Barry beneficiation plant since June 2082 level of 91 405 pit copper processing high-grade ore vein, the main metal ore minerals are pyrrhotite, iron sphalerite, pyrite, arsenopyrite, cassiterite , lead times for Jamesonite ore, chalcopyrite marcasite, Stannite like. The gangue mineral is mainly composed of quartz calcite and a small amount of tourmaline . The ore grade is: Sn 1.27%; Zn 6.25%; S 12.8%; As 0.97%; C 1.98%; TFe 16.72%. At that time, the technical indicators for zinc selection were very low: the concentrate grade was generally only 42 to 38%, and the recovery rate was 30 to 40%. The grade of individual class concentrates was higher than 45% and the recovery rate was only 20 to 30%. After one month of production and debugging indicators have not improved, production is very passive.
The reason is that the metal mineral inlay is finer in size, the pyrrhotite content is high and part of the natural floatability is very good; the ore contains soluble copper salt cadmium salt, which activates the sulfide. Therefore, the separation of the fully floated sulfide becomes very difficult.
According to the characteristics of the ore, the magnetic-floating combined process (see the figure below) is used to obtain good indicators (see table below). 
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The natural floatability sequence of sulfide ore is arsenopyrite-pyrite and most pyrrhotite-iron sphalerite-small amount of pyrrhotite. Only by making full use of the difference in natural floatability can a good technical indicator be obtained with a simpler process and fewer agents.
The lead minerals in China's lead-zinc polymetallic sulphide ore are mainly galena (Dachang is brittle sulphur bismuth ore). The zinc minerals are mainly sphalerite (Huangshaping, Hesan is iron sphalerite), and copper minerals are mainly Chalcopyrite, a few ores except for chalcopyrite contains a small amount of secondary copper minerals (Xiaotieshan, Wuxian, Tianbaoshan, etc.), iron sulfide minerals are mainly pyrite (Xilin: pyrrhotite; nozzle Mountain: pyrite, pyrrhotite).
According to the selection process of China's main lead-zinc polymetallic vulcanization plant, the separation method used in flotation practice can be summarized as follows:
1. Separation of lead and zinc (and sulfur) zinc sulfate (Zhuangding, Bingcun, Zhuji Pb•Sp/Zn, Delan Tara Pb•Sp/Zn), sodium sulfite-zinc sulfate (Xiaxiashan), thiosulfuric acid Sodium-zinc sulfate (Hezhang Pb•Sp/Zn), soda-zinc sulfate (Shuikoushan, Qingshuitang, Mengenjiali), soda-zinc sulfate-sodium cyanide (small amount) (Xilin), soda-sulfuric acid zinc - sodium cyanide (Daxin, Chaihe), zinc sulfate - sodium cyanide (Shan Chengzi silver), potassium permanganate, - zinc sulphate - sodium cyanide (Baoshan), sodium cyanide (Huanren Pb concentrate De-Zn), lime-zinc sulfate (Fankou, Huangshaping, Lechang). Among them, the selection plant using the cyanide-free process accounted for 61%, the less cyanide process accounted for 6%, and the cyanide process was 33%.
2. Separation of copper, lead and zinc (and sulfur) zinc sulfate (He San), zinc sulfate-sodium cyanide (small amount), (into the family, camphor, Tianbaoshan), zinc sulfate-sodium cyanide (Yinshan) , sodium thiosulfate - zinc sulfate - sodium cyanide (small amount) (Tao Lin), Huanren, Zhanggongling plant did not use inhibitors in the copper and lead mixed selection. Among them, the selection plant using the cyanide-free process accounts for 38%, the cyanide process is 50%, and the cyanide process is 12%.
3. Copper and lead separation lead-free float copper scheme: water glass - CMC (He three), sulfurous acid - sodium sulfide (small iron mountain) sulfuric acid - sodium thiosulfate - ferrous sulfate (citron), sodium sulfite - zinc sulfate - sodium Hong chromium (small) (Huanren), sulfite - steam heating - sodium dichromate (small) (Bajiazi), sodium dichromate (Taolin, ZHANGGONGLING) copper flying lead suppression scheme: cyanide Sodium (or sodium cyanide - zinc sulfate) (Tianbaoshan, Yinshan). Among them, the plant with a cyanide-free (chromium) process accounted for 34%, the cyanide (chromium) process was 22%, and the cyanide (dichromate) process accounted for 44%.
4. Separation of zinc and sulfur Commonly used to activate sphalerite with copper sulfate, inhibit sulfide minerals with lime, and sometimes add a small amount of sodium cyanide to strengthen the inhibition of easy-floating pyrite. Individual plants (Zhanggongling, Dome) use a method of inhibiting pyrite by sodium cyanide. There are also a selection of plants that use a small amount of sodium cyanide to inhibit pyrite (5 gram tons of rivers, 8 grams / ton of coix seed). Among them, the plant with non-cyanide process accounted for 82%, the cyanide process was 9%, and the cyanide process was 9%. [next]
It can be seen that the cyanide-free process has been widely used in China. At the same time, due to the significant effect of a small amount of cyanide, the less cyanide process (cyanide dosage below 10 g/ton) has received widespread attention.
The eight sub-plants added 3 g/ton of sodium cyanide in the copper-lead mixed flotation, which increased the recovery of copper and lead in the corresponding concentrate by 2.7% and 1.5% respectively; the Taolin plant was added in the copper-lead mixed Sodium cyanide 3 ~ 5 g / ton, lead recovery can be increased by 2%. Hesan, Xiangxi and Tianbaoshan added good sodium cyanide 1~2g/ton, 6g/ton and 7g/ton respectively in copper-lead mixed-mix, and all achieved good results.
The cyanide-free process and the less cyanide process are still the current direction for the improvement of the lead-zinc polymetallic ore separation process. Some of the selection plants have been continuously improved by carefully studying the flotation behavior of various useful minerals under the existing process conditions, continuously improving and improving the existing processes and cooperating with the measures to strengthen the floating iron.
In the cyanide-free process, the Shuikoushan Plant has established a new pharmaceutical system that replaces sodium cyanide with lime milk. In the lead selection area (also known as the lead-zinc separation zone) and the zinc-sulfur separation zone, the artificial topography is in the high alkalinity pulp, which promotes the common effect of other sorting agents under the condition of no cyanide. The key problem here is to control the pH value. The control range should be different depending on the working conditions and the sorting minerals. For example, the pH value of the lead selection zone is controlled between 9 and 10.5, while the pH value of the zinc-sulfur separation zone is controlled at 11~. Between 11.5.
After adopting the cyanide-free process, compared with the original cyanide process, the recovery ratio of gold and silver is improved under the similar conditions of lead and zinc. The recovery rates of gold and silver enrichment in lead concentrates increased by 4.08% and 0.87%, respectively.
It is worth noting that in addition to eliminating the pollution itself, the cyanide-free process can affect the dissolution of other harmful elements and reduce the pollution of other metal ions (see table below).