Ore characteristics in the process of fine grinding technology
Compare with coarse grinding, fine grinding process technology with many special characteristics. Only find out ore process feature of fine grinding process, in order to strengthen the pertinence of fine grinding grinding, improving grinding efficiency and to alleviate the crush of useful minerals.
(1) narrow particle size range of fine milling process, grinding than small. Fine grinding mill feed particle size is less than 0.3mm, some even as small as 0.1mm, when grinding to the product size up to 0.074mm, grinding than only 4.1 per cent, even grinding to 0.038mm, grinding than just 7.9. Coarse grinding ore particle size is usually up to l0 20mm, part of the plant even as high as above 25mm, mill to the particle size of 0. 3mm grinding ratio of up 33. 3-66. 7 was far greater than the fine grinding when grinding. Due to the fine grinding granularity of scope is narrow, selection of grinding medium size put forward higher requirements, and fewer demands on media types and ratios.
(2) mineral hardness of grinding particle size of attenuation fade, and the effect of fineness of product is growing. Due to uneven mechanical characteristics of ore-, micro-fractures of the same ore particle size the more coarse the more mechanical strength from bad to worse, the more easy to wear. Particle size the more details the better mechanical strength, the more difficult ground. 31 Omm quartz and calcite (Mo Shi hard 152 degrees and 7 respectively) ground under the same conditions so that they are ground into (J. 04mm 90%, quartz 80min hard and soft calcite as long as 50min, Wang called effect of hardness on the efficiency of thin He still exists. In addition, in the same branch of a weight level of wear the same amount of time under the same conditions, resulting in students is less than 19 LU NL particles, arising after the coarse level grinding, fine produce less proof of wear particles as fine as possible. When both hard and soft mineral fine grinding of fine particle levels increased k can also see when hard when fine grinding soft calcite and quartz. Product grinding too fine, emerging gap fine levels yield smaller, prove that grinding particle size the more detailed, Ore hardness of fade, and fineness of product influence gradually increased. This behavior occurs because, on the one hand because the particle size after the thin, macro-and micro-cracks for particle decrease, and also more homogeneous and defect reduction, so even if the soft mineral is also enhanced the strength of, on the other hand is fine grinding conditions deteriorate, grinding process ineffective, when ground breaking low probability. Resulting with thin grinding granularity of both hard and soft minerals as a result of ground velocity difference decreases.