Study on Corn Particle Size Uniformity and Model Construction Based on Roller Mill

PurposeTo study the effect of surface linear velocity and roller gap of the fast roller on the particle size and particle size distribution of corn pulverization.

MethodsTwo-factor experiment design was adopted. The roller gap of roller crusher was 0.5, 1.0 and 1.5 mm, and the linear velocity of the fast roller was 4, 6 and 8 m/s (the speed ratio between the fast roller and the slow roller was 2.5∶1). The particle size of corn samples was determined by BT-2900 dynamic image particle analysis system. The least square method of SAS was used to construct the model and the process parameter calculation prediction model of roller mill was obtained.

ResultsThe geometric mean particle size of weight (d_gw), geometric standard deviation of weight (S_gw) and the ratio of target interval of the finished product were significantly affected by the roll gap of roller crusher (P<0.05). With the increase of the roll gap, d_gw and S_gw increased, and the ratio of target interval decreased. Surface linear velocity, roll gap and their interaction significantly affected the d_gw of finished product (P<0.05). With the increase of fast roller surface linear velocity, d_gw gradually reduced. When the roll gap (X₁) was 0.5, 1.0 and 1.5 mm, and the corresponding linear velocity (X₂) was 8, 6 and 6 m/s, respectively, the ratio of target interval was relatively high, and the crushing effect was better. Process parameter calculation model of roller crusher are: d_gw=701.82X₁−62.23X₂+1000.30; S_gw=0.26X₁−3.70e⁻¹⁷X₂+2.07.

ConclusionBoth linear velocity and roller gap can affect the particle size and particle size distribution of corn pulverization, suitable linear velocity and roller gap could be set up based on feed requirement.