胚芽米碾米机工艺参数的试验研究.pdf

东北农业大学硕士学位论文胚芽米碾米机工艺参数的试验研究姓名:万志华申请学位级别:硕士专业:农业机械化工程指导教师:夏吉庆20080620摘要摘要大米胚芽中含有丰富的蛋白质、脂肪、可溶性糖和多种维生素以及钾、钙、锌等人体必需的微量元素。碾米后胚芽保留率在80%以上,并符合大米等级标准的精米称为“胚芽米”目前,研究能够生产胚芽米的新型碾米机己经成为国际碾米行业的热门课题,而我国胚芽米碾米机的研究尚处于起步阶段,技术不完善,缺乏对实际生产有指导价值的工艺参数。因此,研究新型碾米工艺、设计胚芽米碾米机,对于提高我国胚芽米碾米技术有重要意义。基于此,本试验在结合国内外胚芽米碾米技术的基础上,对影响胚芽米生产的丁艺参数进行探索研究,寻求胚芽米生产工艺在这些参数影响下的变化规律,并优化出适合胚芽米生产的最佳工艺参数,以期为今后的深入研究及实际生产提供一定的参考。本研究的内容和成果主要包括以下几个方面1.设计了胚芽米碾米机试验用样机,对碾米机的主要工作部件进行了设计,对影响胚芽米生产的主要工艺参数进行了计算。确定了碾米辊转速、碾米筋倾角和碾白室间隙为试验因素,留胚率、增碎率和产量为试验评价指标。2.确定三个因素的试验取值范围分别为720r/min1097r/min、115。和8.3mm117m。道过二次回归旋转组合试验,分别得出三个因素对各指标影响的数学模型和变化曲线,并对模型进行F检验、优化、频数分析、单因素和两因素交互作用分析。频数分析表明,碾米辊转速在900/min左右时碾米机的留胚率较高,但在此水平上增碎率较高,产量也较低。在试验取值范围内,留胚率随碾米筋倾角的增大而降低,随着碾白室间隙的增大而升高;增碎率随碾米筋倾角的増大而升高,随碾白空间隙的增大而降低。另外,碾米机的产量随着碾白室间隙的增大而小幅度增加。3.试验表明碾米辊转速、碾米筋倾角和碾白室间隙是影响各评价指标的主要因素,三个因素之间存在一定的交互作用。试验得出留胚率、增碎率和产量达到最优值时所对应的碾米辊转速、碾米筋倾角和碾白室间隙分别为:(876r/min、1、117m),(1068r/min、111.7mm),(1068r/min、1、11.7mm)。4.建立综合评定方程,设定各评价指标的权值,计算出综合评定的一组最优工艺参数。结果表明,碾米辊转速为948r/min、碾米筋倾角为0.86、碾白室间隙为112m为最佳胚芽米生产工艺参数。将此结果进行验证试验,结果表明该组参数达到了胚芽米的碾米要求,对胚芽米碾米机的设计和生产有一定指导意义。关键词:胚芽米碾米机;碾米辊转速;碾米筋倾角;碾白室间隙;留胚率;增碎率;产量Experimental Study of Technologic Parameter forGerm-remained Rice WhitenerAbstractThe germ of rice is rich in protein, fattiness, dissoluble sugar, many kinds of vitamins andmicroelements such as kalium, calcium and zinc. When the germ-remained rate after whitening isabove 80 percent, and rice accords with the grade normal, it is calledgerm-remained rice Atpresent, research of late-model germ-remained rice whitener is a pop thesis of the domain owhitening machine. In China, the research of germ-remained rice whitener is just in the underwayphase. The technology is still faultiness and short of technologic parameters that has instructionalvalue for actual production. Therefore, it has important significance to study new type of whiteningtechnology and design germ-remained rice whitener for Chinese rice process industry. Base onthese, this test combines the whitening technology in China and oversea countries, fathom thetechnologic parameters which influence the process of germ-remained rice. This dissertation questsfor the change law of process technology that influenced by these parameters, optimize them to suitthe process of germ-remained rice. This test expects to offer some reference data for the furtherstudy and actual production in the future. The major contents and results include the following threeaspects.1. Designed a germ-remained rice whitener in order to test. The test designed the main parts ofthe machine, and counted the main technologic parameters that influence the process ofgerm-remained rice It confirmed the rev of roller, the obliquity of veins and gap of the whiteningroom to be the elements. It fixed on the germ-remained rate, the broken adding rate and the outputto be the estimate targets.2. The test confirmed the bound of each element is 720 revolutions per minute to 1097revolutions per minute, 1degree to 15 degrees, 8.3 millimeters to 11.7 millimeters. It used theorthogonal experiments of rotation assemblage of two times, educed the mathematics models andbr