小型饲料搅拌机和平模颗粒机组合使用制备颗粒饲料的工艺研究

[目的] 研究JB-300型精饲料搅拌机和300型平模颗粒机组合使用制备牛羊精补料颗粒饲料的最佳工艺参数。[方法] 测定不同搅拌时间、装载系数对饲料混合均匀度的影响;确定搅拌混合工艺参数的基础上,测定不同玉米粉碎粒度、水分含量对颗粒饲料成型率的影响。以模孔直径、玉米粉碎粒度和水分含量为测定因素,以成型率和硬度的综合加权评分值为指标,确定制备颗粒饲料的最优组合参数。[结果] 搅拌时间为10 min、20 min的变异系数均显著（P<0.05）低于搅拌5 min和15 min。装载系数为80%时,变异系数显著（P<0.05）低于装载系数为70%和60%。玉米粉碎粒度为2 mm和4 mm时,颗粒饲料成型率显著（P<0.05）高于玉米粉碎粒度为6 mm和8 mm。水分含量为10%和13%时,颗粒饲料成型率显著（P<0.05）高于水分含量为16%和19%。影响正交试验综合加权平均分值的模孔直径、玉米粉碎粒度、水分含量的极差分别为18.76、1.64和3.47。[结论] JB—300型精饲料搅拌机混合饲料最佳参数：装载系数为80%、搅拌时间为10 min;300型平模颗粒机制作精补料颗粒饲料最佳参数：模孔直径为4 mm（压缩比为6）、玉米粉碎粒度为4 mm、水分含量为13%。

Development of Pelletized Feed Preparation Technology by Combinatorial Use of a Small Feed Blender and a Flat Die Granulator

[Objective] To determine the best process parameters for preparing pelletized supplementary concentrate of cow and sheep by combinatorial use of a concentrate blender （JB-300 type） and a flat die granulator （300 type）. [Method] The impacts of varied mixing times and loading coefficients on feed blending uniformity were examined. Based on the determined process parameters of blending and mixing, the effects of different corn particle sizes and moisture contents on the molding rate of pelletized feed were assessed. To determine the best combinatorial parameters for preparing pelletized feed, the die hole diameter, corn particle size, and moisture content were used as base measurement factors, and the comprehensive weighted score of molding rate and hardness were used as evaluative index in orthogonal test. [Result] When the blending time was set to 10 min or 20 min, the variation coefficients were significantly （P<0.05） lower than when it was set to 5 min or 15 min. The variation coefficient was significantly lower （P<0.05） when the loading coefficient was 80% than when it was 70% or 60%. The molding rate of pelletized feed was significantly （P<0.05） higher when the corn particle size was 2 mm or 4 mm than when it was 6 mm or 8 mm. When the moisture content was 10% or 13%, the molding rate of pelletized feed was significantly （P<0.05） higher than when it was 16% or 19%. The extreme differences of die hole diameter, corn particle size and moisture content affecting the comprehensive weighted average score of orthogonal test were 18.76, 1.64 and 3.47, respectively. [Conclusion] The optimal parameters of the JB-300 type concentrate blender for feed mixing were loading at 80% and mixing for 10 minutes. The die hole diameter of 4 mm （compression ratio of 6）, corn particle size of 4 mm, and moisture content of 13% were the best specifications of the 300 type flat die granulator for preparing pelletized supplementary concentrate.