筛揉组合式平贝母高效分离装置设计与试验

Design and experiment on high efficient separating device of screening and kneading combined type for fritillaria ussuriensis maxim

针对平贝母筛净率低(含土率高)的问题,通过对平贝母与土壤团聚体物理力学特性试验,测定平贝母和土壤三轴平均尺寸和临界破损压力,结果表明:筛上平贝母土壤团聚体的三轴尺寸不显著,平贝母与筛上土壤团聚体的临界挤压力值显著。基于这一结论,提出筛揉方法的平贝母和土壤团聚物高效分离方案,搭建平贝母高效分离试验装置。计算并确定了筛揉装置揉搓力取值的最佳范围为20~40 N,确定揉搓单体厚度的取值范围在0.2~0.4 cm。设计二次回归正交旋转试验方案,得出喂入量、喂入量平方项与输送筛线速度平方项对筛净率的影响极显著,揉搓力、喂入量与输送筛线速度交互项对筛净率影响显著;喂入量、输送筛线速度平方项对破损率的影响极显著,揉搓力、喂入量与输送筛线速度交互项、喂入量与揉搓力交互项、喂入量平方项对破损影响显著。利用Design-Expert.V8.0.6软件,得出最优参数组合为:喂入量0.68 kg/s、输送筛线速度0.38 m/s、揉搓力36 N时,室内试验筛净率为80.5%,破碎率为12.6%。田间试验表明:该分离装置筛净率平均值为79.18%,破碎率平均值为13.34%,满足平贝母机械化收获的农艺要求。

Aiming at the problem of low screening rate(high soil content)of FUM,triaxial mean size and critical damage pressure of FUM and soil were measured,by means of FUM and soil aggregate Statistical analysis of triaxial dimensions and mechanical properties test.The results showed that the triaxial size of FUM and the soil aggregates on the screen was not significant,and the critical extrusion force value of FUM and the soil aggregates on the screen was significant.Based on this conclusion,the efficient separation scheme of FUM and soil aggregates by screening and kneading method was proposed.The efficient separation test device for FUM was constructed.The optimum range for calculating the kneading force of screening and kneading device was 20-40 N,and the value range of the kneading monomer thickness was 0.2-0.4 cm.The quadratic regression orthogonal rotation test scheme was designed,the results showed that the influence of the feeding amount,the square term of the feeding amount and the square term of the conveying screening speed on the screening rate was very significant,and the kneading force,the interaction between feeding amount and the speed of the conveyor screening had a significant impact on screening rate.Feeding amount and the square term of the speed of the conveyor screening had significant effects on damage.Kneading force,interaction between feeding amount and conveyor screen speed,interaction between feeding amount and kneading force,and the square term of feeding amount had significant effects on damage.By Design-Expert.V8.0.6 software,the optimal parameter combination was obtained:feeding amount of 0.68 kg/s,conveyor screen speed of 0.38 m/s,kneading force 36 N,screening rate of 80.5%,damage rate of 12.6%,respectively.Field tests showed that the average screening rate of the separator was 79.18%,and the average damage rate was 13.34%,which could meet the agronomic requirements of mechanized harvesting of FUM.