Reactor Design for Biocellulose Production to the Aims of Industrial Process

本研究考察了不同生物反应器模式下生产生物纤维素的最有效的培养方法，并在此基础上设计了旋转圆盘生物反应器。它由长20cm、直径15cm的卧式热柱和不锈钢制侧板组成，侧板一侧装有电机驱动、培养基和曝气开口，另一侧装有pH和氧电极、两个阀门。加热后的水通过温度保持在28(]SY+-[)1 C的气缸下的热插孔。培养基pH由1% NaOH水溶液自动控制。经过过滤的空气只向气相进行曝气。培养基初始体积为1800ml，即筒体体积的一半。采用直径为14.4cm的6 - 16目不锈钢网盘作为细菌细胞的载体。将60ml预培养液接种于28ºC水平旋转2-5rpm的反应器中，以2000ml/min的曝气率孵育6d。孵育重复9次。然后检查生物纤维素的总年数，以转速和盘数，或pH控制和曝气条件。生物纤维素生产反应器最有效的培养条件为：14目不锈钢盘是细菌细胞最有效的载体。尽管生物反应器产生的生物纤维素的数量与磁盘的转速（30和50rpm）大致相同，但在50rpm孵育的情况下，有一些生物纤维素的散射速度太快而无法保留在磁盘上。因此，最佳转速为30rpm。曝气进入气相将有助于生产更多的生物纤维素，提高生物纤维素的物理性能，特别是提高片材的杨氏模量。

In this study, the most effective incubation methods for biocellulose production were examined in various mode of bioreactor, and then on the basis of the results, the bioreactor with rotating-disk has been designed. This is composed of horizontal pyrexcylinder of 20cm long and 15cm diameter, and stainless-made side plates equiped with one side of motor-drive, openings for culture medium and aeration, and with another side of pH and oxygen electrodes, two valves. Warmed water is passed through a thermojacked under the cylinder maintained at 28(]SY+-[)1ﾟC.pH in culture medium was automatically controlled by 1% NaOH aqueous solution. Aeration was done only into gas-phase by the filtered-air. Initial volume of the medium is 1800ml, that is half volume of the cylinder. Stainless mesh-disk from 6 to 16mesh of 14.4cm diameter were used as a supporter for bacterial cells. 60ml of preculture was inoculated into the reactor horizontally rotating 2-5rpm at 28ﾟC,and then incubated for 6days with aeration of 2000ml/min. The incubation was repeated 9times. Then total yealds of biocellulose has been examined for rotating speed and number of the disk, or pH control and aeration conditions. The most effective incubation conditions for the reactor of biocellulose production were as follows. 14mesh stainless disk was the most effective supporter for bacterial cells. Although the bioreactor produced about the same amount of biocellulose with respect to rotating speed of the disk, 30 and 50rpm, in the case of 50rpm incubation, there was some scattering of biocellulose too fast to retain on the disk. So the optimum rotating speed is 30rpm. Aeration into gas-phase would contribute to produce more biocellulose and to enhance physical properties of the biocellulose, especially, to increase in Young's modulus of the sheets.