Abstract: In order to separate and recycle eggshells and eggshell membranes, a grinder for separating eggshells and eggshell membranes was designed by shear and grind methods. The main influencing factors are blade type, blade clearance, rotational speed and screen mesh number. The grinder experiment on the dried eggshells was carried out. The improved experimental results showed that the separation rate reached the maximum value of 86.72% and the loss rate was 3.71 % when the rotational speed was 1374 r/min, the 2 mesh number screen was installed and 50°blades with blade clearance of 1mm were adopted. The mass proportion of large eggshell membrane particle was increased. Consequently, the experimental grinder can effectively improve the separation rate of eggshell membranes.