Daye iron ore is a typical "Daye SKARN formula" Cu-rich iron-containing deposits, mainly of useful elements iron, copper, cobalt, sulfur. Iron minerals are mainly magnetite, followed by hematite (mostly imaginary hematite), limonite, and siderite. The minerals recovered by flotation are mainly brass and cobalt-bearing pyrite. Secondly, there are a small amount of pyrrhotite, ferrous iron, pyrite and trace amounts of chalcopyrite and porphyrite. The main gangue minerals are quartz, garnet, white mica, calcite, mica, chlorite, and clay minerals. Statistical analysis of production materials Copper concentrate grade fluctuation range% copper   fine   mine cobalt  fine  mine Feed grade Cu% γ% β Cu β S εCu β Cu β S εS Less than 10 77.89 9.08 38.14 96.62 0.855 32.71 24.18 6.85 10.1~12 59.26 11.22 37.64 95.81 0.714 34.91 38.94 6.94 12.1~14 51.66 13.16 37.15 95.89 0.604 36.26 47.73 7.09 14.1~16 51.48 15.02 36.09 96.41 0.593 38.22 50.02 8.02 16.1~18 41.74 17.12 35.67 94.52 0.712 38.46 60.01 7.56 18.1~20 38.89 19.02 34.82 94.71 0.676 39.34 64.46 7.81 20.1~22 37.73 20.85 34.55 97.12 0.374 38.6 64.83 8.1 Less than 22 39.85 23.17 34.02 96.99 0.478 41.45 64.77 9.52 total average 49.42 14.59 36.5 95.88 0.611 37.08 50.9 7.52 More than 18 average 38.88 21.01 34.46 96.34 0.509 39.8 64.69 8.48 2. Industrial test According to the basis provided by the above test research, the original separation process was modified, and the secondary copper selection operation and one sweeping operation were added. In the beginning of October, the process was completed and put into industrial test. The whole process of flotation after transformation is shown in the figure below. Industrial testing is carried out in two phases. The first phase was from October 1979 to March 1980; from April 1980 to the end of the year, the second phase of production verification. In the fifteen-month industrial test, the copper concentrate reached 19.54~20.14%, exceeding the expected 18% requirement. The copper recovery rate did not decrease significantly, the cobalt sulfur recovery rate was greatly improved, and the process transformation was successful. . The comprehensive indicators before and after the separation process are listed in the table below. [next] Comprehensive analysis before and after process transformation 　 　 　 Changed before 1979 1~9 The first stage October 1979 ~ March 1980 The second stage, April to December, 1980 1981 1982 Mixed flotation Raw ore% αCu 0.488 0.618 0.362 0.457 0.475 αCo 0.022 0.024 0.019 0.02 0.022 Mixed concentrate% γ 5.08 5.72 4.32 4.12 4.4 βCu 7.64 8.85 6.68 8.64 8.28 εCu 79.56 81.95 79.76 77.81 76.66 Separation flotation Copper concentrate% γ 51.21 44.12 31.65 39.87 39.85 βCu 14.43 19.54 20.17 20.95 19.93 εCo 0.2 0.171 0.149 0.156 0.186 εCu 96.72 97.42 95.57 96.68 95.9 εCu total 76.95 79.84 76.23 75.23 73.52 Cobalt concentrate% γ 48.79 55.88 68.35 60.13 60.15 βCu 0.513 0.408 0.433 0.477 0.563 βCo 0.258 0.259 0.257 0.285 0.29 εCo total 31.03 35.09 39.3 34.46 33.57 Rice Cake Mould,Gold Ingot Shaped Cake Mould,Tortoise Cake Mould,Boat Cake Mould OSFE INDUSTRIAL CO.,LTD , https://www.1758cookware.com
Since the commencement of the production of the Daye Iron Ore Plant in 1959, the process has undergone several reforms and now produces iron concentrates, copper concentrates, and cobalt-sulfur concentrates. Before 1979, the copper concentrate grade had been fluctuating around 14%, and the highest year was only 16%. In October 1979, the copper-cobalt (sulfur) separation process was changed. From a coarse one sweep to a coarse two-fine sweep, the copper concentrate grade was increased to 18-20%, and the cobalt sulfur recovery rate was also greatly improved.
1. Factors affecting the quality of copper products The composition of concentrate products According to multi-element analysis, when the copper grade is 16.2%, the iron and sulfur contents are 36.4% and 36%, respectively. The phase analysis shows that the proportion of copper sulfide mainly composed of chalcopyrite is over 97%. At the time of conversion, the sum of iron and sulfur in the concentrate should be about 30%, and actually reach 72% or more. It can be seen that the main reason for affecting the grade of copper concentrate is the low separation precision, which causes a large amount of cobalt-containing pyrite to be mixed into the copper concentrate, resulting in a low copper grade.
Particle size analysis of copper concentrate The results of the sieve analysis indicate that the main reason why pyrite enters the copper concentrate is not the particle size problem, which may be caused by insufficient suppression or insufficient selection.
Research on process structure In the small closed circuit test, two copper selections were added, the copper grade increased from 15.64% to 21.82%, the operation recovery rate decreased by 1.52%, and the sulfur recovery rate increased by 20.21%. It shows that the copper grade can be greatly improved by adding and strengthening selected operations.
Statistical analysis of the means of production The statistics of the means of production from May 1978 to July 15th, 1979 (the following table) indicate that: (1) the increase in copper concentrate grade will not result in a significant reduction in recovery; 2) The grade of copper concentrate is not very close to the grade of the ore, but closely related to the sulfur content of the concentrate. In the statistical range, the copper content of copper concentrate decreased by 1% on average, and the copper grade increased by about 3%. (3) From the production point of view, the recovery rate of copper mainly depends on the grade of copper and the copper content of cobalt concentrate. As long as the copper content of the cobalt concentrate is not increased, the recovery rate of copper will not be significantly reduced, and the recovery rate of cobalt (sulfur) will be greatly improved.
[next] 