Teach you to determine the most reasonable size of the mined product
For the crushing operation, the larger the particle size of crushed mineral, the higher the productivity of the crusher, the lower the cost of crushing. However, for grinding operations, the production capacity of the grinding machine will decrease with the increase of the ore size. Conversely, if the ore size is reduced, the production capacity of the grinding machine will be improved and the grinding cost can be reduced. In general, in conventional crushing and grinding processes, the energy consumption of crushed ore is small, while the energy consumption of grinding is much greater. According to statistics, crushed ore is only 12%-25% of the energy consumption of grinding, and the efficiency of crushed ore is higher than that of grinding. Therefore, in the crushing system, the particle size of the mineral product should be reduced as much as possible, and the crushing effect should be fully utilized to improve the processing capacity of the grinding machine, which is called “multi-breaking and less grindingâ€. Due to the reduction of the particle size of the crushed ore product, the diameter of the steel ball as the grinding medium can also be reduced, thereby increasing the grinding and stripping effect, increasing the production capacity of the grinding machine, and the steel ball consumption can also be reduced. The final crushing granularity of the size and scale beneficiation plants have a great relationship, see Table 2-1 Table 2-1 The production capacity of the concentrator and the reasonable size range of the ball mill feed The larger the size of the ore dressing plant, the more significant the economic effect of reducing the grain size of the grinding ore. For example, it is calculated that for a concentrating plant with a scale of 10 million tons/year, when the final particle size of the crushed ore is reduced from 20 to 0 mm to 12 to 0 mm, although the crushing capacity is reduced by 1/3, the ball mill is The capacity can be increased by 16%, the equipment investment can save 10.51 million yuan, the installed power is 3855 kW, and the power consumption per section is 3058. 5 kWh, accounting for about 10% of the whole plant's electricity consumption. Of course, the data in Table 2-1 cannot be used mechanically, and other factors must be considered. For example, equipment factor, if the last section is a short-head cone crusher , the final particle size of the crushed product can not be less than 6~8 mm. In order to avoid the difficulties that occur during closed circuit work, the final ore size of the ore is often set at 8, 10 mm, or even larger, sometimes to 10 to 15 mm. If you install a roll machine, you can get a final grain size of 4 to 5 mm, but consider configuration and management issues. During the design, it should be ensured that the discharge port of each section of the crusher is appropriate and must not exceed the minimum allowable discharge port width. In order to obtain the smallest crushed product granularity under the condition that the equipment can work normally. The optimum particle size of the crushed ore product has a great relationship with the crushing process, see Table 2-2. Table 2-2 Appropriate particle size of the crushed product when crushing medium friable ore by different crushing processes Serial number Process name Plant size Suitable for open pit mining Suitable particle size / mm Suitable for underground mining Suitable particle size / mm Last break Type of crusher 1 2 3 4 5 Two-stage open process Two-stage closed circuit Three-stage open process Three-stage closed circuit process Four-stage closed circuit process Small Medium Medium Medium and large Large - - 25~30 8~15 3~6 25~30 10~15 20~25 8~10 —— Standard type Short or standard Short head Short head Roller In summary, when determining the most reasonable size of the crushed ore, it is mainly related to the size of the ore dressing plant, the crushing equipment used, and the crushing process used. According to the principle of “multiple crushing and less grindingâ€, it is advisable to obtain the smallest crushing size. Iron Box,Iron Boxes,Iron Box Packaging,Food Packaging Dongguan Tielangtou Hardware Products Co., Ltd , https://www.nbtinboxtlt.com Production capacity of ore dressing / (ton / day) The most reasonable grain size of the ball mill (the largest size of the nugget) / mm Production capacity of ore dressing / (ton / day) The most reasonable grain size of the ball mill (the largest size of the nugget) / mm 500 1000 10~15 6~12 2500 4000 5~10 4~8