本试验旨在研究同一配方下,玉米不同粉碎粒度对颗粒饲料加工质量和育肥猪生长性能的影响。选用1.5/2.0、2.0/2.0、2.0/2.5、2.5/2.5、2.5/3.0和3.0/3.0 mm孔径的筛片对玉米进行粉碎,分别得到几何平均粒径为303.91、346.08、356.81、358...本试验旨在研究同一配方下,玉米不同粉碎粒度对颗粒饲料加工质量和育肥猪生长性能的影响。选用1.5/2.0、2.0/2.0、2.0/2.5、2.5/2.5、2.5/3.0和3.0/3.0 mm孔径的筛片对玉米进行粉碎,分别得到几何平均粒径为303.91、346.08、356.81、358.51、373.29和387.70μm的玉米原料,采用同一配方和相同的加工参数(其他原料粉碎筛片孔径2.0 mm,制粒调质温度80℃、模孔直径3.0 mm、长径比9∶1)加工成含不同粉碎粒度玉米的饲粮。选取108头平均体重为(62.68±5.59)kg的"杜×长×大"杂交猪,随机置于6个组(每个组3个重复,每个重复6头猪,公母各占1/2),分别饲喂含不同粉碎粒度玉米的饲粮,试验周期为8周。结果表明:随着筛片孔径的增大,粉碎能耗从9.02 k W·h/t降低到6.86 k W·h/t,制粒能耗从19.06 k W·h/t升高到22.30 k W·h/t;粗蛋白质体外消化率随玉米粉碎粒度的增加呈现上升的趋势,其中2.5/2.5 mm组最高,且显著高于1.5/2.0 mm组(P<0.05);颗粒硬度2.5/3.0、3.0/3.0 mm组显著高于其他组(P<0.05);随粉碎粒度的增加饲粮干物质表观消化率降低,其中1.5/2.0和3.0/3.0 mm组分别为84.43%和80.62%,后者比前者降低了4.5%,且差异显著(P<0.05);随玉米粉碎粒度的增加饲粮粗蛋白质表观消化率整体呈现下降的趋势,且1.5/2.0 mm组粗蛋白质表观消化率为86.14%,与其他各组差异显著(P<0.05);各组平均日增重和料重比均无显著性差异(P>0.05),2.5/2.5 mm组平均日采食量最高,但与各组间无显著性差异(P>0.05)。根据本试验结果,建议育肥猪饲粮玉米粉碎粒度采用2.5/2.5 mm筛片孔径。展开更多
Results of experimental measurement of solids mass flux profiles in a high density circulating fluidized bed riser over a wide operating condition are described.The existence of three solids flux radial profile regime...Results of experimental measurement of solids mass flux profiles in a high density circulating fluidized bed riser over a wide operating condition are described.The existence of three solids flux radial profile regimes:core-annular,parabolic and U-shaped is found.A model for all the three regimes is proposed and correlations of model parameters are obtained.Comparison of predicted solids flux profiles with experimental data is very promising.The correlations for the boundaries of the three regimes and the radius of core for core-annular regime are obtained.展开更多
文摘本试验旨在研究同一配方下,玉米不同粉碎粒度对颗粒饲料加工质量和育肥猪生长性能的影响。选用1.5/2.0、2.0/2.0、2.0/2.5、2.5/2.5、2.5/3.0和3.0/3.0 mm孔径的筛片对玉米进行粉碎,分别得到几何平均粒径为303.91、346.08、356.81、358.51、373.29和387.70μm的玉米原料,采用同一配方和相同的加工参数(其他原料粉碎筛片孔径2.0 mm,制粒调质温度80℃、模孔直径3.0 mm、长径比9∶1)加工成含不同粉碎粒度玉米的饲粮。选取108头平均体重为(62.68±5.59)kg的"杜×长×大"杂交猪,随机置于6个组(每个组3个重复,每个重复6头猪,公母各占1/2),分别饲喂含不同粉碎粒度玉米的饲粮,试验周期为8周。结果表明:随着筛片孔径的增大,粉碎能耗从9.02 k W·h/t降低到6.86 k W·h/t,制粒能耗从19.06 k W·h/t升高到22.30 k W·h/t;粗蛋白质体外消化率随玉米粉碎粒度的增加呈现上升的趋势,其中2.5/2.5 mm组最高,且显著高于1.5/2.0 mm组(P<0.05);颗粒硬度2.5/3.0、3.0/3.0 mm组显著高于其他组(P<0.05);随粉碎粒度的增加饲粮干物质表观消化率降低,其中1.5/2.0和3.0/3.0 mm组分别为84.43%和80.62%,后者比前者降低了4.5%,且差异显著(P<0.05);随玉米粉碎粒度的增加饲粮粗蛋白质表观消化率整体呈现下降的趋势,且1.5/2.0 mm组粗蛋白质表观消化率为86.14%,与其他各组差异显著(P<0.05);各组平均日增重和料重比均无显著性差异(P>0.05),2.5/2.5 mm组平均日采食量最高,但与各组间无显著性差异(P>0.05)。根据本试验结果,建议育肥猪饲粮玉米粉碎粒度采用2.5/2.5 mm筛片孔径。
文摘Results of experimental measurement of solids mass flux profiles in a high density circulating fluidized bed riser over a wide operating condition are described.The existence of three solids flux radial profile regimes:core-annular,parabolic and U-shaped is found.A model for all the three regimes is proposed and correlations of model parameters are obtained.Comparison of predicted solids flux profiles with experimental data is very promising.The correlations for the boundaries of the three regimes and the radius of core for core-annular regime are obtained.
