A scheelite is an ultra-poor porphyry scheelite deposit containing trace amounts of molybdenum minerals. The development of such extremely poor mineral resources should be based on the comprehensive recovery of various elements, which is not only the need to build resource-saving mines, but also Conducive to improving the economic benefits of the mine. First, the nature of the ore The results of multi-element analysis of ore minerals are shown in Table 1. The results of tungsten phase analysis are shown in Table 2. Table 1 Multi-element analysis results of ore chemistry Table 2 % of raw ore tungsten phase analysis results Process mineralogy studies show that scheelite ore recovery of the most important objects, views of wolframite, molybdenite, pyrite, yellow copper ore, gangue mineral species, high content of mainly quartz, sericite, potassium feldspar. The structure of scheelite is mainly characterized by disseminated type, fine vein type and agglomerate structure, among which the fine-grained disseminated structure is dominant. Second, the test results and discussion The test adopts the principle flow of first floating sulphide ore and then floating scheelite. In order to enhance the selective flotation of scheelite and calcium-containing gangue minerals during flotation, sodium carbonate was used as a regulator, water glass was used as an inhibitor, and 731 oxidized paraffin soap was used as a collector . The experiment found that the variety and high content of gangue minerals are the main factors affecting the enrichment of scheelite. Therefore, it is important to effectively suppress the gangue minerals during the rough selection operation, so that high-grade flotation coarse essence can be obtained. The ore and coarse concentrates have been removed from the gangue minerals through three blanks to improve the grade of the crude concentrate WO 3 entering the analytical operation, which is the key to obtaining high quality tungsten concentrate. In addition, the suppression of gangue minerals in selected operations is also an effective measure to improve the quality of concentrate products [1 , 4 ~ 7] . (1) Influence of grinding fineness The grinding fineness test procedure is shown in Figure 1, and the results are shown in Figure 2. Figure 1 The preferred sulfur sulphur-white tungsten normal temperature rough selection test process Figure 2 Grinding fineness test results It can be seen from Fig. 2 that as the fineness of the grinding increases, the grade of the tungsten coarse concentrate gradually decreases. However, improving the fineness of grinding is beneficial to the dissociation of scheelite and gangue minerals, and significantly improves the recovery rate of tungsten. Based on the roughing operation of tungsten for this operation, the tungsten recovery rate is mainly increased. Considering the comprehensive consideration, the test determines that the appropriate grinding fineness is -200 mesh and accounts for 80%. (II) Test of rough selection conditions of white tungsten at room temperature 1. Na 2 CO 3 dosage test Na 2 CO 3 can create an alkaline environment that is easy to float. But also to adjust the viscosity of the slurry, sludge dispersion, the pulp can precipitate Ca 2 +, Mg 2 +, and a variety of heavy metal ions, these ions to overcome the adverse effects of the flotation water, thereby changing the surfactant scheelite [2 , 3] . The Na 2 CO 3 dosage test procedure is shown in Figure 1, and the test results are shown in Figure 3. Figure 3 Sodium carbonate dosage test results It can be seen from Fig. 3 that Na 2 CO 3 has an inhibitory effect on gangue minerals. As the amount of Na 2 CO 3 increases, the grade and recovery rate of tungsten coarse concentrate gradually increase. When the amount of sodium carbonate is 1600g/t, the concentration of tungsten concentrate is higher. The maximum value is reached in synchronization with the recovery rate indicator. Therefore, it was determined that the amount of tungsten crude Na 2 CO 3 was 1600 g/t. 2, water glass dosage test Water glass is the most commonly used dispersant and gangue inhibitor in flotation of scheelite. The amount of water glass is small, the gangue mineral can not be effectively suppressed, the coarse concentrate contains low tungsten content; the large amount of water glass is white tungsten. The mine is inhibited and the tungsten recovery rate is not up [4] . The test procedure for water glass usage is shown in Figure 1, and the test results are shown in Figure 4. Figure 4 Water glass dosage test results It can be seen from Fig. 4 that the grade and recovery rate of tungsten concentrates increase rapidly before the amount of water glass is increased to 1000g/t; after the amount of water glass exceeds 1000g/t, the grade of tungsten increases slightly with the increase of the amount of water glass. The recovery rate has dropped rapidly, considering the use of water glass to select 1000g/t. 3, collector 731 dosage test At present, most of the collectors for the use of scheelite in China are mainly 731 oxide paraffin soap. The 731 dosage test procedure is shown in Figure 1, and the test results are shown in Figure 5. Figure 5: Collector 731 dosage test results It can be seen from Fig. 5 that the grade and recovery rate of tungsten concentrate increase rapidly before the dosage of 731 is increased to 500g/t; after the dosage of 731 exceeds 500g/t, the tungsten grade decreases rapidly and the recovery rate decreases slowly. Considering 731 dosage, choose 500g/t. (III) Selection test of tungsten coarse concentrate The floatability of calcium-containing gangue minerals in white tungsten tungsten at normal temperature coarse ore concentrate is close to that of scheelite, and the separation is very difficult. Therefore, the selection of white tungsten coarse concentrate is very important. Experiments on the selection of tungsten coarse concentrates at room temperature and heating selection show that the heating selection is suitable for the treatment of the ultra-lean scheelite. After adding water glass, the floatation characteristics of scheelite are much better than those of calcium-containing gangue minerals under high temperature, high concentration and strong agitation. At this time, after the slurry is diluted and selected, a good floating tungsten index can be obtained [5] ] . According to the test, the temperature of the slurry is controlled at 90 °C, and the effect of stirring for 1 h is better. Under this condition, the water glass dosage test was carried out according to the flow of Fig. 6. According to the test results, it was determined that the amount of the heated water glass was 4000 g/, and the tungsten concentrate grade was 63% or more. Figure 6 Test procedure for heating flotation water glass (4) Process test The test uses a rough two-sweep two-precision process to pre-desulfurize, and the desulfurization tailings is subjected to a sulphurite ore open-circuit test through a rough two-sweep six-time selection process. Due to the low grade of the original ore, the blank selection of gangue minerals is removed to improve the grade of tungsten coarse concentrate before entering the analytical operation, and then the water glass is added and analyzed and diluted three times under high temperature, high concentration and strong stirring. On the basis of the open circuit process test, the heating closed circuit process test was carried out. Due to the return of the first three blanks of the selected mines to the rough selection of tungsten and the return of other intermediate mines, the coarsening of the slurry in the tungsten roughing operation is difficult to control, and the concentration of the chemicals is “runningâ€, resulting in roughing operations. Unstable, the indicators are not ideal. Finally, the medium-mineral step-by-step return plan was selected. In order to ensure the quality of the crude concentrate entering the analytical operation and reduce the impact of the return of the mine, the third selected medium mine and the analyzed middle mine are merged and returned to the second selection operation. The closed circuit is shown in Figure 7. The closed circuit test results are shown in Table 3. Figure 7 closed circuit test process Table 3 Closed-circuit process test results The test process and results show that the process foam is stable and easy to control, and the ideal index of 60.31% tungsten concentrate grade and 83.91% recovery rate is obtained. Third, the conclusion 1. The molybdenum-containing tungsten ore has a low content of useful metal minerals, a molybdenum content of 0.01% or less, and a WO 3 content of only about 0.1%, but the molybdenum and tungsten have a recovery value, and the process flow and the pharmaceutical system are not complicated, only tungsten. More selections. 2, using the preferred float sulfur molybdenum white tungsten at room temperature rough selection coarse concentrate heating selection process! For the ore containing WO 3 0.115%, the obtained white tungsten concentrate contains WO 3 60.31%, the recovery rate is 83.91 % of mineral processing technical indicators. references [1] Liang Youwei. Experimental study on ore dressing of scheelite in a certain area of ​​Guizhou [J]. Comprehensive Utilization of Mineral Resources, 2010 (2): 3~6. [2] Xie Guang, Wu Weisong. Handbook of Mineral Processing (Volume 8, Volume 2) [M]. Beijing Metallurgical Industry Press, 1990. [3] Zhang Shuhong. Experimental study on mineral processing of a molybdenum-containing scheelite[J]. China Tungsten Industry, 2007(3): 10~. [4] Wang Guosheng, Guan Zezhen, Han Zhaoyuan. Experimental study on mineral processing of a scheelite in Hunan[J]. Comprehensive Utilization of Mineral Resources, 2008(3): 9~12. [5] Gao Yude, Jiang Qingmei, Feng Qiming, et al. Experimental study on beneficiation of a scheelite[J]. Metal Mines, 2008(8): 52~55. [6] Zhao Lei, Deng Haibo, Li Shiliang. Research progress in flotation of scheelite[J]. Modern Mining, 2009(9): 15~17, 26. [7] Deng Lihong, Zhou Xiaotong. Study on the beneficiation process of recovering black and white tungsten ore from the original secondary fine mud [J]. Metal Mine 2008 (11): 148 ~ 151. Specialty Tapes Shenzhen Chengxing Packing & Material Co.,Ltd , https://www.cxpack.com
October 30, 2021