Design and Experimental Evaluation of a Spiral Feeding Device Based on Friction Characteristics of Wheat Straw

The aims of this study were to achieve working stability and continuity of the straw fibre extruder(D200)to improve the transportation efficiency of pretreated straw materials mulch film.Based on a theoretical analysis of wheat straw friction characteristics and the mechanics model of wheat straw transport,a tilting variable-diameter spiral feeding device matched the designed straw fibre extruder(D200-type).Experimental researches were performed by using the orthogonal test method of the L16(45)to obtain the optimal parameter combination.The spiral angle,the speed of the screw shaft and the moisture content of straw raw materials were selected as influencing factors,and feeding efficiency was selected as the objective indicator.The results showed that the spiral angle,the rotating speed of screw shaft and the moisture content of straw raw materials had very significant effects on the feeding efficiency(p<0.01).The order of the extent of the influence of parameters on the feeding efficiency of wheat straw raw materials from high to low was the moisture content,the spiral angle and the speed of screw shaft.When the maximum transfer efficiency per unit time of the inclined spiral feeding device was 1040.8 kg·h-1,the spiral angle was 40?,the speed of screw shaft was 200 r·min-1 and the moisture content was 65%.Verification experiment proved the feasibility of straw fibre extruder designed.

高通量测序研究膨化秸秆生物发酵饲料对辽育白牛肠道菌群的影响

为研究膨化秸秆生物发酵饲料对辽育白牛肠道菌群的影响,选用体重相近[(300~350)kg]的健康无疾病的辽育白牛40头(10月龄、无阉割),随机分成4组,分别为:对照组(100%基础精料+黄贮饲料),试验1组(80%基础精料+膨化秸秆生物发酵饲料),试验2组(70%基础精料+膨化秸秆生物发酵饲料),试验3组(60%基础精料+膨化秸秆生物发酵饲料)。试验的预试期30 d,正试期130 d,试验牛自由采食和饮水,每天观察牛群的采食情况及健康状况。试验结束,每组随机选取3头牛进行直肠取粪便,用于肠道菌群的高通量测序分析。结果发现:(1)粪便菌群高通量测序分析发现:在门水平上,拟杆菌门、厚壁菌门为对照组和试验组粪便中的优势菌门。在属水平上,孢杆菌属为粪便细菌中的优势菌属。添加膨化秸秆生物发酵饲料的试验组中分解纤维素的厚壁菌门、梭菌属IV增加,尤其试验2组较对照组差异显著(P<0.05),且试验组丁酸产生菌梭菌属Xl Va相对丰度有所提高,但差异不显著(P>0.05)。(2)粪便细菌Alpha多样性比较发现:试验组香浓指数(Shannon index)、艾斯指数(Ace index)、赵氏指数(Chao index)与对照组比较呈提高趋势,而辛普森指数(Simpson index)呈下降趋势,表明试验2组牛肠道内微生物多样性提高。

秸秆纤维制取机配套强制喂料装置的优化设计及试验

为辅助秸秆纤维制取机高效制取秸秆粗纤维,解决喂料过程中因人工劳动强度大、喂料不连续造成粗纤维加工质量下降等问题,设计竖直向下螺旋强制喂料装置。在喂料装置结构及工作原理分析基础上,以秸秆长度、螺旋轴转速和秸秆含水率为试验因素,以输送量为评价指标,采用3因素5水平二次正交旋转中心组合方法实施试验。结果表明,(1)各因素对大豆秸秆输送量贡献率主次关系为:秸秆长度、螺旋轴转速、秸秆含水率;(2)当参数组合为秸秆长度60~120 mm、螺旋轴转速160 r·min-1、秸秆含水率78%~90%时,满足纤维制取机1 000 kg·h^(-1)喂入量要求。研究为D200型桔杆纤维制取机高效生产优质纤维奠定基础。

秸秆膨化机进料装置的设计

为了解决秸秆物料加工利用过程中物料进料时产生的架桥、搭拱、挂壁从而导致的进料不连续、不均匀的问题,提出了二级料仓的双螺旋进料装置,该装置采用长方体料仓设计,消除斜面,使物料在料仓中不会发生架桥、搭拱、挂壁等现象,达到上料方便,进料连续、均匀的目的。

膨化秸秆微生物发酵饲料对杜寒杂交肉羊瘤胃发酵的影响

[目的]以粗饲料作为唯一变量,研究膨化秸秆微生物发酵饲料对杜寒杂交肉羊瘤胃发酵的影响。[方法]选择81只3月龄、体重为(23±1.0)kg的杜寒杂交羔羊,随机分为对照组(70%精料+30%干秸秆)、试验Ⅰ组(70%精料+30%膨化秸秆微生物发酵饲料)和试验Ⅱ组(70%精料+30%膨化秸秆微生物发酵饲料,再添加占日粮总蛋白浓度10%的膨化缓释尿素,NPN≥100%),每组3个重复,每个重复9只羔羊。试验期共75 d,预饲期15 d,正饲期60 d。[结果]试验Ⅱ组的NH3-N和BCP的浓度与试验Ⅰ组和对照组相比显著(P<0.05)提高,试验Ⅰ组和对照组差异不显著(P>0.05)。组间VFA的各项指标差异不显著(P>0.05)。[结论]膨化秸秆微生物发酵饲料+NPN对瘤胃发酵起到一定的促进作用。