| The development and utilization resources are a matter very important to the national policy and people's livelihood. At present, about 95% of energy, 80% of industrial raw materials and 70% of agriculture production material resources will consume a large amount of energy. The mining, mineral processing and smelting consume 15% of the country's energy produced. The mining and ore-dressing enterprises are the main energy consumers. In ferrous and non-ferrous mines, the mining consume 1/3 of electricity energy, and ore-dressing consume the rest 2/3 of electricity energy. Energy consumed by mineral grinding account for 1/2 of the total energy consumed by the mill, or about 1/3 consumed by these enterprises. According to statistics abroad, about 3～5% of the total energy produced in the world is consumed only for mineral grinding. In the country, energy consumption for mineral grinding is still higher, general over 5%. Therefore, reducing energy consumption in grinding is an important task both for the country and others.The country is planning to realize economized society rationalized economy, and maintainable development. To achieve these aims, every trades should spare no effort to reduce energy consumption. Particular attention should be paid to mineral crushing and grinding in mines because their energy consumption is very great and thus it possesses large margin of cutting down the consumption. In the research on mineral crushing and grinding, we find the energy utilization rate of the mineral grinding is very low. Only 1% of the consumed energy goes to generate new faces for the minerals. So raising the energy conversion efficiency is the radical way. As known to all, crushing more and grinding less, or substituting crushing for grinding to descend the size of products can make the energy move forward. This is one way to raise energy conversion. The another important way is to adjust grinding media's parameters such as precisionize the ball diameter so as to further heighten grain's crushing probability. Research conducted home and abroad indicates that the efficiency of mineral crushing is higher and energy consumption is lower comparing with that of mineral grinding. Energy consumption of grinding a unit of mineral is decuple that of crushing the same amount of mineral. Only trying to moving energy forward to reduce the size of grains and not precisionizing the ball diameter can not yields a notable effect. Besides, precisionization of ball diameter demands the reduction of grain size. So the method of energy consumption'distribution forward-moving combined with ball diameter precisionization put forward in this thesis is an effective way to cut down energy consumption of crushing and grinding.From the purpose and task of grinding, we can see that it is only secondary important to reduce the grain size. The most important thing is to make mineral grains be fully separated. Therefore, the ball diameter precisionization is not the demand of reducing energy consumption but also that of the following processing. So the ball diameter precisionization is a very important work. Duan's semi-theory formula provides the basis for computing the required precision ball diameter. The industrial experiments on the ball precisionization technique conducted in several mill show:(1)The mill's productivity has increased by 10～20% in the case of the same grain size distribution of the mill's feeding and discharging.(2)The mineral unit separation degree has increased 5～ 6% percentage points on condition that the size distribution of the grinding products has not changed.(3)The recovery has increased 1～3% percentage points and the concentrate grade also risen on the same ore dressing condition.(4)The consumption of steel ball has decreased by 10～20% for the same quality ball.(5)The unit electricity consumption of grinding has decreased by 10～20% for the same ball loading system.(6)The mill's noise has descended more than 5dB.(7)The life of grinder's lining board has prolonged 30%.The distribution of energy consumption forward-moving theory based on the research of law of grinding energy consumption is one of the effective ways of increasing mill productivity and reducing energy consumption and the ball precisionization theory based on work principle of grinding media is another effective way. The technique of combining the two ways will yield the results of reducing energy consumption to a high degree and other advantages. The thesis expounds the industrial experiments and their results of application the new technique to production practice in Dahongshan Copper Mill, Shizishan Copper Mill and Lala Copper Mill. The main conclusion:(l)In the third stage in Dahongshan Mill, by adopting the way of precisionization theory of steel ball loading and replenishing conducts the following results: The grinding's production has increased by 60% from 53.24t/h to 85.42t/h(in 2005) for a grinder. The fineness of grinding products(-200 mesh) has increased by 5 percentage points. The copper recovery increase 1～2% percentage points and the grade of copper concentrate rinsen by 0.5%. The iron by recovery increase by 6～7% percentage points and the grade of iron concentrate rinsen by 3%. The steel ball consumption has decreased by 16～20%. The electricity consumption decreased by 36% from 26 kw·h/t to 16.6 kw·h/t. The above results obtains under the grain size of 15～0 mm. If the grain size decrease to 12～0mm, a grinder's production will increase to 96t/h, the electricity consumption decreased by 47.3% to 13.7 kw·h/t.(2)In Shizishan Mill, by the same way, the mill's production has increased by 18.92% from 1850t/d in the past to 2200t/d at present. The electricity consumption decreased by 15.7% from 7.38 kw·h/t to 6.22 kw·h/t. The copper recovery increase by 2% percentage points and the copper concentrate grade rinsen by 0.55 percentage point. The fineness of grinding products has increased by 8.26 percentage points.(3)In Lala Mill also, the mill's production has increased by 20% from 4000t/d to 4800t/d. The electricity consumption decreased by 16.73% from 6.99 kw·h/t to 5.82 kw·h/t.The industrial experiment shows that the new technique is highly effective and beneficial. In a word, the combination of the energy consumption'distribution forward-moving theory based on the law of grinding energy consumption and the ball precisionization theory based on work principle of grinding media effects notable results in reducing energy consumption and rising production in mill.
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