玉米秸秆皮瓤分离装置的设计及其试验研究

发布时间：2019-01-29 19:12

【摘要】：玉米秸秆作为一种重要的生物质能源,没有得到有效的利用而遗弃或焚烧,不仅污染环境,而且浪费资源。如何能充分利用玉米秸秆资源,提高其利用价值是一个亟需解决的问题。玉米秸秆其皮含有较多的木质素与纤维素,可用作造纸制板的原材料;其瓤含有丰富的粗蛋白和粗脂肪,可用作优质动物饲料与酿酒的原材料。为了实现玉米秸秆资源高效利用化,必须将其合理有效分离。本文通过对玉米秸秆物料特性分析与前人研究的基础上,设计了一种玉米秸秆皮瓤分离装置,并对该装置进行了可行性试验研究。本文主要研究内容及结论如下:(1)玉米秸秆皮瓤分离装置总体设计与工作原理。该皮瓤分离装置其主要由喂入装置与剪切装置构成。喂入装置主要对秸秆产生压缩与划切作用,压缩过程中因玉米秸秆皮瓤材料特性的差异性,使得秸秆皮瓤产生塑性变形,导致皮瓤结合处部分分离;划切过程中,齿型刀片的齿刃在进入与离开秸秆时,不仅破坏了齿刃处的玉米秸秆皮瓤结合状态,且带动了周围秸秆的皮,破坏了齿刃周围的秸秆皮瓤结合状态,进一步扩大了皮瓤分离程度。剪切装置主要作用是将部分分离的秸秆在定刀与切刀的挤压与切割作用下均匀分离。(2)喂入装置与剪切装置的结构设计及其关键零件有限元分析。喂入装置的结构设计主要包括调节机构、喂入辊、齿型刀片等零件设计;剪切装置的结构设计主要包括刀片、刀架、刀轴等零件设计。运用三维建模软件对各关键零部件进行实际建模,借助于ANSYS有限元分析软件对喂入装置与剪切装置的关键零部件进行强度校核,得到了各零部件在极限载荷的应力分布与变形特征。结果表明,其关键零部件在典型工况下的强度与变形均在合理范围内,为喂入装置与剪切装置的制造提供了一定的理论依据。(3)玉米秸秆皮瓤分离装置的试验。经预试验与理论分析可知,喂入辊转速、上下喂入辊齿间隙、切刀转速等因素对玉米秸秆皮瓤分离效果有较大影响。选取以上三个因素为试验因素,分离率、均匀度为评价指标,在自行设计的皮瓤分离装置上进行试验研究。试验结果表明:喂入辊转速、齿间隙与切刀转速均对两个评价指标有显著影响,其中齿间隙与切刀转速的交互作用对分离率有显著的影响,喂入辊转速和切刀转速的交互作用不仅对分离率有显著的影响,而且对均匀度也有着显著的影响。优化后得到玉米秸秆皮瓤分离装置的最优参数组合为:当喂入辊转速为393r/min,齿间隙为5.86mm,切刀转速为925r/min时,分离率为85.71%,均匀度为85.31%。
[Abstract]:As an important biomass energy, corn straw is abandoned or burned without effective utilization, which not only pollutes the environment, but also wastes resources. How to make full use of corn straw resource and improve its utilization value is an urgent problem to be solved. The skin of corn straw contains more lignin and cellulose, which can be used as raw material for papermaking board, and its flesh is rich in crude protein and fat, so it can be used as raw material for high quality animal feed and wine making. In order to realize the efficient utilization of corn straw resources, it must be separated reasonably and effectively. Based on the analysis of the material characteristics of corn straw and the previous studies, a device for separating corn straw skin and pulp was designed, and the feasibility of the device was studied. The main contents and conclusions of this paper are as follows: (1) the overall design and working principle of corn straw rind and pulp separation device. The skin pulp separating device is mainly composed of feeding device and cutting device. Feeding device mainly produced compression and cutting effect on straw. Due to the difference of material characteristics of corn straw pulp during the compression process, plastic deformation of straw pulp resulted in partial separation of skin and flesh bond. In the process of cutting, when the tooth blade enters and leaves the straw, it not only destroys the binding state of the corn straw skin, but also drives the surrounding straw skin, and destroys the combination state of the straw flesh skin around the tooth blade. The separation degree of skin and flesh was further expanded. The main function of the shear device is to separate the partially separated straw evenly under the extrusion and cutting action of the fixed knife and the cutter. (2) the structural design of the feeding device and the shear device and the finite element analysis of the key parts. The structural design of feeding device mainly includes adjusting mechanism, feeding roller, tooth blade and other parts design; the structural design of shear device mainly includes blade, tool holder, cutter shaft and other parts design. Three dimensional modeling software was used to model the key parts and the strength of the key parts of feeding and shearing device was checked by ANSYS finite element analysis software. The stress distribution and deformation characteristics of the components under the ultimate load are obtained. The results show that the strength and deformation of the key parts are within a reasonable range under typical working conditions, which provides a certain theoretical basis for the manufacture of feeding and shearing devices. (3) the experiment of corn straw husk pulp separation device. Through pre-test and theoretical analysis, it can be seen that the factors such as feeding roll speed, upper and lower feeding roller tooth clearance, cutting tool speed and so on have great influence on the separation effect of corn straw pulp. The above three factors were selected as experimental factors, the separation rate and evenness were selected as the evaluation indexes, and the experimental study was carried out on the self-designed pulp and skin separator. The results show that the speed of feeding roller, tooth clearance and cutter speed have significant effects on the two evaluation indexes, among which the interaction between tooth clearance and cutter speed has a significant effect on the separation rate. The interaction of feed roll speed and cutter speed not only has a significant effect on the separation rate, but also has a significant effect on the uniformity. After optimization, the optimum parameters of the separation device were obtained as follows: when the feed roll speed was 393r / min, the tooth gap was 5.86mm, and the cutter speed was 925r/min, the separation rate was 85.71 and the uniformity was 85.31.
【学位授予单位】：沈阳农业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：S226

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