THERMAL PROPERTIES OF PACKED COTTONY PAPER DURING DRY DISTILLATION PROCESS

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Carbonic materials like as the carbon black and the activated carbon are very useful for various industries. Grinding paper to the cottony and carbonizing it, authors found it shows about 75% activity of the commercial activated carbon. Therefore, it is considered the wasted cottony paper which has large surface area is available as the material of the activate carbon. Considering the design of the carbonization equipment of the cottony paper, thermal properties like as thermal diffusivity, thermal conductivity, specific heat and density of the packed cottony paper during the dry distilllation process is necessary.In this report, the effective thermal diffusivity kappa_<eq> Of packed cottony paper in the semifinite cylindrical vessel was experimentally obtained by heating continuously and uniformly from the outside and measuring the outer surface and center position temperatures of the cylinder. Namely, after considering the generation of heat and the shrinkage of the volume during car … More bonization, kappa_<eq> was decided by changing the assumed kappa_<eq> so as to match the measured center position temperature and the calculated temperature obtained as numerical solution of the one dimensional and unsteady differential-difference equation of heat conduction with the measured boundary conditions.As a result, the shrinkage ratio of the sample radius during the dry distilllation process did not change until near 300ﾟC,then decreased rapidly in the region above 300ﾟC and approached a constant value in the region above 450ﾟC.And, the apparent density for each temperature raising rate also decreases rapidly in the region between 300 and 350ﾟC and increases by way of minimum value and approaches a constant value gradually in the region more than 500ﾟC.Concerning to kappa_<eq> of cottony paper, it increases gradually with increment of temperature till about 300ﾟC and then suddenly increases owing to an exothermic and decomposite reaction. After showing the maximum value at about 400ﾟC,it decreases rapidly and approaches gradually to some value. Less