In recent years, semicontinuous mining technology has been widely used in large open-pit coal mines. In this mining technology, mobile crusher is the key equipment. Since 1970s, many coal mines in China have had to change the mining technology due to the lack of such equipment, which has increased the mining cost. The development of large mineral crusher can not only provide reliable and efficient equipment for open-pit coal mine, meet the requirements of semi-continuous mining technology, but also fill the gap in the design and manufacture of mobile (semi-mobile) crusher, so that the level of Chinese manufacturing crushing equipment will rise to a new level. The new double-tooth roller crusher is light in weight, small in size, low in height, large in particle size and has a large crushing ratio. It is an ideal equipment for semi-continuous mining technology in various open-pit coal mines. The study of the new mineral sizers in our country is only beginning and we are in the imitate design stage. The calculation of power is a key link in the design of a crusher, which is directly related to the success of the subsequent design. Theoretical and experimental research has been conducted on the calculation method of the new mineral sizers in this paper, which provides a theoretical basis for the design.
A general formula of crushing energy consumption is proposed, dA=-0(1), where dA is the energy consumed when the particle size reduces dx; C,α is constant; x is the particle size. Integrate the above equation, then 4=-c-c. In equation (2), D is the average particle size of the material before crushing; d is the average particle size of the material after crushing. a=2,a=L, and a=0.5 were substituted into the above formula respectively, and Rittinger, Kick-Kirpichev,.Bond formula recognized by the mineral processing industry was obtained. Theoretically, Rittinger formula only considers the energy consumption of surface area increase during crushing, Kick-Kirpichev formula only considers the deformation energy before crushing, and Bod formula is just the geometric average of the previous two formulas. In fact, the actual energy consumption is the sum of the surface area plus the deformation energy. The feeding size is different, and the proportion is different. In coarse crushing, due to the large volume of materials, deformation energy consumption accounts for a large proportion, and relatively speaking, from before crushing to after crushing, due to the increase of surface area, the required power consumption will increase sharply. Therefore, the above three formulas have different ranges in application. The formula is suitable for fine grinding, the Kick-Kirpichev formula is suitable for coarse crushing, and the Bond formula is in between.
The new mineral sizers being a new aircraft type, there is no empirical formula to adopt. For example, m is Bond work index (kW·h/t) according to the universal formula proposed by Charles; d is the particle size of the component that accounts for more than 80% of the discharge particle size (m; D is the particle size of the component that accounts for more than 80% of the feeding particle size (m); i is a constant exponent. It is difficult to determine the size of the exponent i using this formula. So let's figure out the range of i. The Bond work index of some rocks and coal in Yuanbaoshan open-pit coal mine is as follows: 8.72kW·h/t coal, 12.40kW·h/t sandstone; Coarse sandstone 17.52kW·h/t. 1250 New mineral sizers: Production Q=2100tWh, discharge size d=2×10μm, feed size D=5×10m. For three different materials, the power N(N'=WH·Q) consumed at different values of i can be calculated according to formula (3). The relationship between N' and i is shown in Figure 1. As can be seen from the figure, when i< At 0.45, N will increase sharply, and the power required by the three materials is very different from that of > At 0.5, the power obtained will be smaller than the actual situation. mineral sizers are therefore advisable: 0.45< i< 0.5.