Papers by Author: Ze Hong Wang

Abstract: The internal parameters of ball mill are very important in the grinding process and have significant impact on the grinding results. Accurate measurement of the internal parameters of ball mill is crucial and indispensable for optimization and control of grinding process. In this paper, a novel tri-sensor measurement method was used to measure the external signals (i.e., bearing pressure, sound intensity and power consumption) of ball mill. Mathematical models, which link the external signals of ball mill with its internal parameters, were established to predict the internal parameters of ball mill. Experimental results showed that the mathematical models could directly predict the internal parameters of ball mill once the external signals were obtained. The tri-sensor measurement method and the mathematical models proposed in this paper provided a new way and solid basis for optimization and control of ball milling.

Abstract: Dongguashan copper ore is one of a complex copper sulphide ores containing various metal minerals in Tong ling area. In this paper, in order to simplify the complexity of traditional lime process, the process of Cu-S bulk flotation-regrinding-separation is discussed and exploited. A good quality of Cu concentrate and S concentrate are obtained respectively after Cu-S separation by using calcium hypochlorite as depressant. A good separation results are derived through this process, and high efficiency of calcium hypochlorite used as depressant and feasibility of the process are confirmed.

Abstract: An extension of the classical Obriemoff experiments has been set up to measure the fracture energy of mica. This experimental system will be entirely independent of slurry rheology. CTAB (Cetyl Trimethyl Ammonium Bromide), sodium tripolyphosphate, sodium hexametaphosphate, and tri-sodium citrate are used as grinding aids in this study and the fracture energy has been measured for mica in air, water, and water with the addition of various concentrations of these grinding aids. The results show that the fracture energy of mica in water is about half of what it is in air. Grinding aids are shown to reduce the fracture energy of mica, but not dramatically. Addition of grinding aids reduces the fracture energy by a further 10-20%, with tri-sodium citrate appearing to be the most effective. For each grinding aid there appears to be an optimal concentration, typically around 10 mmol. An experiment is also done with sodium chloride at a range of concentrations to investigate the mechanism of these grinding aids, but no reduction in fracture energy (compared to water) was observed, hence the molecular-level mechanism of action of these grinding aids remains unclear. The effect of solution pH values on the fracture energy are also investigated using tri-sodium citrate and sodium chloride. The results show that the solution pH value may effect on the fracture energy of mica. So, in practice, both concentration and pH value of solution are important for getting better grinding results.