Aerodynamic characteristics of lotus seed mixtures and test on pneumatic separating device for lotus seed kernel and contaminants

Lotus seed hulling is the first process in rough processing, which is removing the tough shell that covers lotus seed kernel. Generally, it can utilize the mechanical processing method. After processing, the mixtures of lotus seed kernel, lotus seed shell, kernel debris and a small amount of imperfectly shelled lotus seed can be yielded. In this paper, a negative pressure, pneumatic separating method was proposed to separate lotus seed kernel and shell. Firstly, the density parameter, the moisture content and the shape parameter of lotus seed mixture constituent were measured. The test results showed that the density parameters of lotus seed kernel, lotus seed, shell and kernel debris were 1 080, 1 042, 1 210 and 1 163 kg/m super(3) respectively, the moisture content of lotus seed kernel, unhulled lotus seed (with imperfectly shelled lotus seed), shell and kernel debris were 7.35%, 3.91%, 12.36% and 12.45% respectively.