Research And Application Of Stone Coal’s Superfine Crushing And Modification Technology Used For Rubber

The stone coal that has less carbon content、low calorific value and high ash content is a kind of polymetallic ore. Our country is rich in stone coal resources that reserves of about 64,000 million tones. At the moment, the application areas of stone coal is mainly in the following several aspects:(1)fuels and energy;(2)building materials;(3)extraction of rare metals;(4)farm fertilizer. Because of its’ property, the stone coal is hard to apply in other fields. In this paper, we consider the rising of the rubber packing market for rubber reinforcing filler, so we try to instead carbon black with stone coal that prepared by ultra-fine grinding and surface modification.The stone coal is modified by using five kinds of modifier after ultra-fine grinding, this paper discusses the effect of different kinds of modifier on the rubber’s reinforcing property. We found that the effect of modified stone coal on the rubber’s reinforcing property is enhanced, the effect of modified B、D、E is more significant. At the same time,we also studied the effect of modifier’s usage on the 4.5μm stone coal’s reinforcing property, and the results showed the better usage of modifier B、D、E are 1.5%、2.0%、1.5%,respectively. In addition, we discussed the effect of the usage of modifier E on the different particle size stone coal, found that the better usage of modifier E for 3.5μm、4.5μm、5.5μm stone coal are 2.5%、2.0%、1.5%,respectively. it indicated the smaller particle size of stone coal need more modifier usage to achieve better modification effect.In pilot, we conducted a series of exploration and technical transformation, through the parameter optimization of main feed 1.1-1.2A/27Hz、classifier 90A/40-42Hz、fan current 170-175A/45-47 Hz, the yield of product that particle size is 4.5μm can be increased from 1.3T/h to 3T/h. The tensile strength of the product reinforcing natural rubber is increased from 18.76 MPa to 20.10 MPa,the tear strength is increased from 24.19KN/m to 27.59KN/m, than the laboratory tests of the stone coal reinforcing performance after technical transformation. When the N330 carbon black and technical transformation product of particle size is 4.5μm are used simultaneously,with the increased proportion of the N330 carbon black, the mechanical properties of vulcanized rubber is also increased. The results showed: when it satisfies the mechanical properties of the rubber, we can partly instead of N330 carbon black with stone coal to reduce the production cost of the products, or use modified stone coal and N330 with the ratio of 2:3 to instead of N660 carbon black.Through the comparative analysis of stone coal production cost and user formula cost, adding and using stone coal superfine powder can bring significant economic benefits for the user.