Experimental study on re-election of pyrite
I. Overview
Nanjing Yuntaishan pyrite located in Jiangning District of Nanjing, located Yuntaishan mine ore mining low-grade segment overall, the main useful minerals as sulfur iron ore, with an average of around 17%, direct sales difficulties. However, the size of the ore inlay is relatively coarse, and it is possible to try to use the re-election method to improve the grade. Through the research on the gravity optionality of the ore and the grades of various grades of ore, it is a reasonable process for the high-grade fine ore to produce mixed minerals in the sulfuric acid plant.
Second, re-election test - pyrite separation
(1) The ore sample comes from the mining and selection workshop. The crushed sieve is divided into 7 grades, the particle size range is -20+0mm, and the original ore grade is 17.02%.
(2) Instruments, utensils, and pharmacy
Instruments: balance, crushing sample preparation equipment, mixer
Vessels: washbasins, sample pots, sieves, beakers, volumetric flasks, mesh spoons, etc.
Pharmacy: two mercury iodide, potassium iodide
(III) Brief description of the test process
1. Take 6 kg of ore sample, divide into -20+3, -3+0 two grades, -20+3 grade sample on the 3mm sieve, rinse with water, collect the sieve on the sieve, dry, weigh, sieve the sample preparation, test ;
2. Weigh 1.5kg of potassium iodide and 1.86kg of mercury diiodide, add 537.6ml of water, mix and stir until fully dissolved, and measure the specific gravity;
3. Take the above heavy liquid to prepare 300ml of heavy liquid with specific gravity of 2.85, 2.75, 2.70, 2.65 g/ml;
4. Drying and cooling the sieved materials collected in the first step, and then dividing them into five products in the order of large to small in the above-mentioned heavy liquids, respectively washing, drying, weighing, crushing and preparing the products. ,assay.
(4) Test results
See Table 1 for the results of the -20+3 mm pyrite heavy liquid test.
Table 1 Results of heavy liquid separation test of -20+3 mm pyrite 
It can be seen from the above table that after the heavy liquid separation of pyrite with a particle size of -20+3mm, if the ore with a specific gravity of less than 2.85 g/cm3 is completely discarded, the work recovery rate is 84.2%, the working grade is 21.65%, and the operation is discarded. The rate is 50.9%. Considering the washing, the -3+0 mm ore in the ore, the following results can be obtained.
From the above table, we can see the pyrite ore with a grain size of -20+0mm. If the mine with a specific gravity of less than 2.85g/cm 3 in the -20+3mm ore is discarded, the total recovery rate is 92.0%, and the total concentrate is obtained. The grade is 23.29%, the total scrap rate is 34.3%, and the grade in the waste mine is 3.92%, which is much lower than the utilization value of pyrite. When the ore grade reaches more than 22%, the broken into powder ore can be directly into the mixed mine boiling furnace to roast the sulfuric acid.
According to the table I data, draw the optional curve l curve and b curve as follows:
l reverse-S shape curve, Yuntaishan pyrite ore showed good reselection Alternatively, an easily dressing stone.
According to the above test, we can get the following conclusions:
(1) When the Yuntaishan pyrite ore is broken to -20 mm, the ore grade can be increased from 17.12% to 23.29% under static conditions, and the recovery rate can reach 92.0%. At this time, the rejection rate is 34.3%. The scrap grade is 3.92%. The indicator is ideal.
(2) According to the analysis of l curve and b curve, the Yuntaishan pyrite ore is easy to beneficiated for re-election. When it is broken to a certain particle size, the ore grade is improved by re-election method, and the standard of directly reaching the commodity mine is It is entirely possible and economically viable.
(3) The concentrate after re-election can be directly crushed into fine ore into the sulfuric acid workshop and calcined. Or enter the flotation, select the high-grade concentrate, which can greatly improve the processing capacity of flotation, greatly reducing the cost of flotation.
references:
[1] "Selection of ore selectivity", Xu Zhong, etc., Central South Institute of Mining and Metallurgy;
[2] “Fracture and Grinding†Li Qiheng, Kunming Institute of Technology;
[3] “Gravity Dressing†Gu Guojie, Wuhan Institute of Chemical Technology.
4 Ohm Speakers,Full Range Driver,Full Range Speaker,Full Range Car Speakers
Ningbo Sonice Electroacoustic Science and Technology Co., Ltd. , https://www.secspk.com