玉米秸秆除杂的研究

通过利用筛分分析及风选原理,对颗粒粒径分布的测定进行了系统性的研究,以玉米秸秆混合物中各组份粒径分布的测定为例,设计沉降室并分析了内部流型及秸秆除杂效果。结果表明,采用筛分分析方法与风选沉降方法测得的粒径分布结果基本相同,当颗粒粒径大于0.045mm时,以上两种方法具有等效性。结合这两种方法测定了玉米秸秆中沙石及秸秆粒径分布曲线。在所设计的沉降室中,内部流型符合水平方向及垂直方向上阻力系数为定值的假设,计算出的理论值也与实验值吻合,并在秸秆与沙石质量百分含量关系图中找到最优点A,其秸秆收率达到57%,纯度为95.7%。

Study of impurity removal from corn mixture

Determination of particle-size distribution(PSD) was systematically studied with methods of sieving analysis and wind winnowing.The order and method of determination of PSD of the two components,corn and sand,of corn mixture were studied.The structure of settling chamber was designed and the internal flow was studied.The effect of impurity removal from corn mixture was tested using the settling chamber.The results showed that data of the two methods were basically the same,and the two methods were equivalent when particle size was greater than 0.045 mm.PSD of the two components of corn mixture were determined and calculated.The internal flow in the settling chamber was in line with the assumption that the drag coefficients of horizontal and vertical direction were constant.The theoretical value was consistent with the calculated value.The optimum point A was found in diagram of mass content of corn-sand.The yield of corn was 57%,and the purity was 95.7%.