碳纤维复合材料回收装置中物料停留时间研究

EXPERIMENTAL RESEARCH ON THE INFLUENCE OF THE SHAPE OF MATERIAL TO RESIDENCE TIME IN A RECOVERY DEVICE OF CARBON FIBER COMPOSITES

为保证所回收的碳纤维能及时有效地被排出,用EPE泡沫为示踪物料,在建立热氧裂解法回收碳纤维的装置上,用实验法测定了卧式流化床反应器的流化曲线。经分析流化曲线得出临界流化速度和带出速度并经公式计算确定了临界流化速度和带出速度,考察不同形状物料及混合物料在主反应器内的停留时间。结果表明,流化床内临界流化速度为0.15m/s,颗粒带出速度为0.24m/s;物料形状对其在床内停留时间影响较大;单一形状物料在流化床内停留时间由长到短依次为圆柱体、长方体和球体;球体物料最易排出;混合物料在床内停留时间由长到短依次为球体与圆柱体混合物料、长方体与球体混合物料和长方体与圆柱体混合物料;长方体与圆柱体混合物易排出;为使回收碳纤维尽快排出流化床,可采用长方体和圆柱体混合物料或单一的球形物料进行热试验研究。

Fluidization curve of reactor and the influence of the shape of material to residence time have been studied with EPE foam as a tracer material on the basis of establishing experiment device of recycling carbon fibre using the oxygen pyrolysis method in order to ensure that recycled carbon fibre can be moved. The minimum fluidization velocity and carryover rate have been determined through calculating with formulas and analyzing fluidization curve from experiment. The experimental results show that the critical fluidization velocity and carry-over velocity of solids are 0.15m/s and 0.24m/s, respectively. The shape of material affects its residence time in fluidized bed. The residence time order from long to short of single shape materials is the cylinder, rectangle and sphere in turn in the fluidized bed; mixture residence time order from long to short is sphere and cylinder, sphere and rectangle, rectangle and cylinder mixture. Mixture of rectangle and cylinder or single sphere as pyrolysis material should be used to thermal test in order to discharge recycled carbon fiber as soon as possible.