渐扩底流口旋流器分级性能试验研究OA北大核心CSTPCD

A gradually expanding underflow structure was proposed to address the problem of rope-like discharge phenomenon at high underflow concentration of hydrocyclones in grinding and classification systems,which can lead to blockage of underflow orifices,causing escape of coarse particles in the overflow and reducing separation accuracy.Experimental research was conducted on the underflow orifice structure,and the influence of the gradually expanding angle of underflow orifices on product concentration,particle size,comprehensive classification efficiency,and underflow yield under different concentrations was analyzed.The results indicate that as the feed concentration of the hydrocyclone increases,the scattering angle of the underflow discharge decreases.When the feed concentration is greater than 10%,a rope-shaped discharge phenomenon occurs in the hydrocyclone,changing to a gradually expanding underflow orifice can reduce the rope-shaped discharge phenomenon.The scattering angle of the underflow discharge of the hydrocyclone shows a trend of first increasing and then decreasing as the angle of the underflow orifice gradually expands.When the feed concentration of the hydrocyclone is greater than 10%,the scattering angle of the underflow discharge of the hydrocyclone shows an overall corresponding relationship with the classification performance of the hydrocyclone.Under different feed concentrations,selecting an underflow orifice with corresponding gradually expanding angles can achieve the best separation effect of the hydrocyclone.At 25%feed concentration,the content of +20 μm particle size in the overflow material from the conventional underflow orifice of the hydrocyclone is 62.44%.Compared to conventional underflow orifices,the gradually expanding underflow orifice structure can make the content of +20 μm particle size in the hydrocyclone overflow decreased by 22.54%;The comprehensive classification efficiency of the hydrocyclone for-40 μm particle size is the highest when the underflow angle is 60°,an increase by 15.72%compared to the underflow angle of 20°.