【作者】 刘彬；

【导师】 童明伟； 吴厚玖；

【作者基本信息】 重庆大学 ， 工程热物理， 2008， 博士

【摘要】 随着有机物产品的大规模生产和利用,废弃有机物也随之增多,例如农作物废弃物、有机食品加工的残留物,城市生活垃圾等等,这类污染源所造成的生态破坏和环境污染已经日益严重,如何有效的处理和利用废弃有机物成为摆在人们面前的一个重要的问题。有机物因为其本身的生物性质,在热科学领域表现出与无机物质不同的特性,对于有机物质的传热传质过程和热物性的分析与研究,能够为有机物质的综合利用打下基础。本文对柑桔榨汁加工后的皮渣残留物和葡萄酒胶的发酵过程以及发酵产物的获取过程(主要为干燥过程)中的传热传质规律进行分析与研究,以探寻其如何有效的处理和利用,本文主要研究内容为:①有生物内热源存在下的传热过程分析与研究对微生物发酵反应过程中的热源进行了分析,探讨了温度对微生物发酵过程的影响,分别对葡萄酒胶和柑桔皮渣发酵过程中的微生物菌体活性与温度的关系进行了研究,获得了细胞生长速率与温度之间的关联式,证明在微生物适宜生长温度范围内,温度的提高能够加快生长速率,但过高的温度也会促使微生物细胞的衰老和死亡。随着发酵物料比热值增大,单位质量发酵物料的温升将减小,从而对微生物的生长速率的变化产生影响,据此本文在阿列纽斯公式的基础上考虑到发酵物料的热物性——比热容值对微生物比生长速率变化趋势的影响,因而提出比热容的修正关联式。分析了柑桔皮渣和葡萄酒胶发酵过程中发酵反应的自身反应热,进行无控温的自然发酵实验,确定单位时间内释放的生物热,同时对生物介质的热物性进行测定和分析。将发酵过程作为含有生物内热源下的非稳态传热过程,对固态发酵多孔固体基质中的传热传质过程进行了分析,对微生物发酵传热特性及其温度场的分布特性进行了研究。进行了温控下的发酵过程实验,在发酵箱内的控温水管内通入冷热水,作为温控冷热源。确定单根控温水管周围的温度影响范围和影响方式,进行含有生物内热源条件下的热传导分析,得出不同发酵介质下计算水管周围空间温度分布的数学模型,进行数值计算以确定周围空间的温度分布,并与实验结果进行比较,得到了较好的吻合。②发酵产物流态化干燥过程的传热传质分析进行了柑桔皮渣发酵产物的获取和应用研究,通过实验研究柑桔皮渣发酵产物在流化干燥床中的干燥特性以及干燥过程传热传质的机理。实验结果表明,对于经过预处理的发酵柑桔皮渣介质,采用流态化干燥方式可以获得较好的干燥效果。采用单因素分析方法分析干燥参数如介质温度(T)、介质风速(v)、床层高度(H)和初始含湿率(W0)对干燥速率和单位能耗的影响,实验结果表明:随着介质风温的增大,干燥速率加快;风速越大干燥速率越快;床层高度越高干燥速率越慢;皮渣初含越大,干燥速率也越大。实验结果也表明这些干燥参数对干燥速率的影响在干燥后期会减弱。对正交实验的结果进行了极差分析,得出了干燥因素对干燥速率和单位能耗的影响程度,其结果表明,干燥参数对干燥速率的影响次序为,W0>T>v>H。干燥参数对单位能耗的影响次序为,v>T>W0>H。对发酵柑桔皮渣流态化干燥过程进行传热传质分析,根据能量守恒定律,导出流化床内的局部换热系数计算式,分析了各个流化干燥因素对换热系数的影响,利用最小二乘法原理采用origin7.5回归分析软件对实验结果进行拟合,得到了发酵柑桔皮渣流态化干燥过程中传热传质的经验表达式。并对发酵柑桔皮渣流化干燥过程的气固两相流场进行数值模拟,从颗粒运动行为特性方面揭示流化床中气、固两相高效率传热传质的本质。③发酵柑桔皮渣工业化成套设备的研制与应用介绍了发酵柑桔皮渣中试过程,并进行发酵饲料小批生产与饲喂实验,证明柑桔皮渣发酵饲料完全可以作为一种饲料原料用于生产奶牛精料补充料。更多还原

【Abstract】 Effective disposal and utilization of biologic products refuse has become one of the most important global issues recently as waste biologic substances such as crop waste, residues of biologic food procession, and municipal refuse caused by large-scale production of biological product are severely destroying environmental balance and polluting ecosystem. And in the study of thermal, biologic substance shows different thermal characteristics based on its own biological quality, therefore, the research and analysis on the mass and thermal transition process of biological substances would be helpful as preparation of the industry application.This dissertation is based on the research and analysis of mass and thermal transition rules during fermentation process of oranges peels waste after juice extraction and acquisition process of fermentation outcome; it also explores further usage of those rules. It contains 3 parts of research:①The research of the thermal transfer process of microorganism with biology inner heat sourceThe heat release in the fermentation course is analyzed, and the influence of the temperature on the growth of microorganism is also discussed. The growth velocities of microorganism in wine fermentation and fermentation of the orange peels are researched, the relations between growth velocities of microorganism and temperature are obtained, and the conclusion shows that temperature increase accelerates the growth velocities of microorganism within appropriate temperature range; however overheat also accelerates the aging and death of microorganism cells. With the consideration of the specific heat capacity, the modification of the specific growth velocities is put forward. And the wild fermentation without temperature control was observed, the heat release of fermentation is investigated, also the thermal characteristics are measured.With considered of the microbial fermentation course as an unsteady thermal transfer process with a biology inner heat source, the heat and mass transfer in the porous Substrate are analyzed, and the thermal transfer characteristics and temperature distribution in the course are researched. The experiments with temperature control are made. The influence method and range of the single temperature control pipe are defined. With the consideration of the inner heat source investigated formerly, the unsteady heat transfer is analyzed, and the expressions of temperature distributions are obtained. The results from calculation agree with the experimental results well.②The research of the law of thermal and mass transfer in fluidized drying process about the zymotic orange peels.The disposal and application of the zymotic orange peels are discussed, the drying mechanism of the orange peels and the law of thermal and mass transfer in drying process are researched.According to the experiment result, the fluidized drying method is suited for the drying of zymotic orange peels. The method of single factor analysis is adopted to analyze the influence to the drying characteristic of drying parameters such as the air temperature(T), the air velocity(v), the height of bed layer(H)and the initial moisture content(W0)etc. The result shows that the dry velocity will be faster with the rise of the air temperature or velocity; Besides, the dry velocity will slower when the height of bed layer or the initial moisture content get higher. However, the influences of these dry parameters on the dry velocity become slowly after some minutes. The method of orthogonal experiment is used to analyze the importance of these dry parameters on the drying characteristics. The result shows that the importance of dry parameters influence on the dry velocity is following: W0> T>V >H, while the importance of dry parameters influence on the consumption of unit energy is obtained: V >T > W0>H.The thermal and mass transfers for the gas-solid fluid bed of zymotic orange peels drying are researched. Base on the energy conservation, the expression for local heat transfer coefficient is educed; the influences on the heat transfer of fluid parameters are analyzed. And the regression expression of thermal and mass transfer is obtained based on the experimental data. Then the mathematical simulations for the gas-solid fluid behavior are made.③The industry design and application for the zymotic orange peels The industry experiments of zymotic orange peels are introduced, the experiments of cow feeding are made to prove the zymotic orange peels can use for a complementarity for milk cow feed.更多还原