Heat-conduction of reconsolidated cotton-stalks during the hot_pressing process | 棉秆重组材热压传热的研究

Chinese. 研究板坯含水率、目标密度、热压温度及板材厚度4个因素对棉秆重组材板坯中心层升温的影响，为制定棉秆重组材的热压工艺提供参考。采用先进的温度在线测量手段，测定棉秆重组材热压过程中板坯中心层的温度，分析板坯含水率、目标密度、热压温度及板材厚度与棉秆重组材板坯中心层升温速度的关系。棉秆重组材板坯热压时中心层温度的变化曲线可分为3个阶段，即水分开始气化前的快速升温段、水分气化时的恒温段和水分基本气化完的慢速升温段。在快速升温段，板坯中心层的升温速度随着板坯含水率、热压温度的增加而加快，随着目标密度、板材厚度的增加而减小；在水分气化时的恒温段，随着板坯含水率、目标密度、板材厚度的增大，气化段的时间延长，热压温度越高，气化段时间越短；在慢速升温段，热压温度高，板坯升温速度快，板材厚度、目标密度大的板坯升温速度慢，板坯含水率对慢速升温段的升温速度几乎没有影响。在棉秆重组材板坯热压过程中，板坯含水率、热压温度、目标密度和板材厚度对板坯中心层升温速度均有不同程度的影响。

English. The study offered basic law of heat-conduction of reconsolidated cotton-stalks in order to make technological plan. The temperature of mat’s central-layer was measured in the hot-pressing process. The relations between the rising velocity of temperature of mat’s central-layer and moisture content of mats, density, hot-pressing temperature, thickness were analyzed. The results showed that in the fast-rising phase of temperature, the growth speed of temperature rose with the increase of moisture content of mats or hot-pressing temperature, and decreased with the increase of density or thickness of mats. The time of the constant temperature phase prolonged with the increase of moisture content, density or thickness of mats, and shortened with the temperature increase. During the slow-rising phase of temperature, the growth speed of temperature reduced with the increase of density or thickness of mats, and rose as the temperature increased. Moisture content of mats had little effect on the growth speed of temperature in the slow-rising phase. The curves of temperature changing of mat’s central-layer could be divided into three stages: the fast-rising phase of temperature, the constant temperature phase and the slow-rising phase of temperature. During the hot-pressing process of reconsolidated cotton-stalks, moisture content, hot-pressing temperature, density and thickness had effect on growth speed of temperature of mat’s central-layer.