Research Of The Micro-stage Grinding Technique

Not only aiming at the existing problems in our mine companies' production, but also combining with the study of the grinding technique in recent years and its development trend in our country and foreign countries, this paper has proposed a new orientation micro-stage grinding process which is to realize a staged-grinding in the same ball mill. The research had been successfully applied in several large mines. The results showed that a remarkable improvement of the effciency of grinding (at most rise 16% or so) and a good effect of energy saving and consumption reduction could be reached under the condition of electric current of running mill and the finess of the grinding. As a result, this research is very important both in the improvement of our mine companies' ecmomical effects basing on their current resources and in the study of grinding principles.The main study work could be devided into follwing six parts:1. The study of the principles of the micro-stage grinding technique;2. The study of both the ncessity of the micro-stage grinding technique's application in theory and the the feasibility of the micro-stage grinding technique's application in practice;3. The study of the the principles of ball mill discharge-end's abrasioncapacity and the different situation of the mill liners' wear after the application of the micro-stage grinding technique;4. The study of the adaption of the micro-stage grinding techniqueunder different grinding situations;5. The study of the main factors' adjustment which could cause the effect of the micro-stage grinding technique;6. The study of the application of the micro-stage grinding technique in a large copper mine.Based on mentioned studies before, this paper has deduced the following results:By fixing the different surface-shape liners in ball mill's inner barrel along with the axis of ball mills, the micro-stage grinding technique makes the minerals' grinding process more correspond to the grinding principles than traditional. So this technique could be applied in nearly all kinds of grinding condition because its property which conforms to the truths'.After the application of the micro-stage grinding technique, the law of distribution of the steel balls in the process of grinding is more in line with the mineral demands for crushing forces because of the changes of both the law of steel balls' movement and the ball mill liners' wear. And those changes raise the ball mill discharge-end's abrasion capacity greately.Since the micro-stage grinding technique has different adaption according to different factors which could cause grinding efficiency (such as the ore hardness, mill product fineness, the type of ball mill et. al), the ball mill liners should be designed systematically under different grinding conditions. It should be strengthed that not only the ball mill discharge-end's abrasion capacity but also the ball mill inlet end's impact capacity. Furthmore, grinding conditions should be adjusted correspondly too.The applications of the micro-stage grinding technique in several kinds of mine show that compared with the traditional grinding technique, the micro-stage grinding technique can increase grinding efficiency and improve grinding results greatly, and that it can reach a good effect of energy saving and consumption reduction. Moreover, ball mill's transformation requires little fund merely so that this technelogy can be promoted easily. Then the prospect of its application will be cheerful because of those mentioned advantages. At the same time, this technique has discovered a new orientation study in research of grindingprinciples and its practice.