| Widely applied in the cement and mining industry, high pressure grinding rolls (HPGR), as a kind of new-style material grinding machinery, which follows the principle of "deeper crush and less grind", is enjoying the advantages of energy saving and high efficiency in crush. Material crush behavior of HPGR has a direct impact crush results, but because of the randomness of the diversity of materials, non-continuity, heterogeneity and distribution of defects, there is not in-depth research on the crush behavior. Based on a scientific research project of some corporation, the thesis takes research on the crush behavior of HPGR. It can not only enrich the material crushing theory, but also plays an important role in the development of HPGR. The main content could be read as below:(1) The thesis analysis grinding model of HPGR, deduce thematrix model of material grinding process, throughput model, power draw model, and particle size distribution model, reveals the influence of key process parameters on energy consumption, processing and product particle size distribution of the material density, the roll gap, roll speed.(2) Single particle crush and interparticle crush are imitated via the method of RFPA (Real Failure Process Analysis) and analyzed to improve the followings:1)the maximum principal stress plays a leading role in the crushing process;2) the influences of material strength, homogeneity, and environmental constraints in the breakage process;3) different dimensional effects between single particle crush and interparticle crush;4) materials mixed impurity effects of the crush behavior.(3) Research on material crush behavior and energy variation in HPGR is taken via the method of PFC to analyze its crush process in accelerating zone, extrusion zone and releasing zone, and the different influences on the crush process by different particle size and roll speed. (4) HPGR crush experiments are conducted to confirm the validity of the theoretical derivation and the simulation analysis. |
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