Reactor Design for Biocellulose Production to the Aims of Industrial Process

本研究在不同的生物反应器模式下对生物纤维生产最有效的培养方法进行了考察，并在此基础上设计了转盘式生物反应器。它由长20 cm、直径15 cm的卧式热解筒和不锈钢侧板组成，侧板一侧设有电机驱动、培养基孔和曝气口，另一侧设有pH和氧气电极、两个阀门。温水通过钢瓶下面的热套，保持在28SY+-1ﾟC。培养液中的pH由1%氢氧化钠水溶液自动控制。过滤后的空气只向气相中曝气。介质的初始体积为1800ml，即圆柱体的一半体积。用直径14.4 cm的6~16目不锈钢网片作为细菌细胞的载体。将60ml预培养物接种于28ﾟC水平旋转2~5rpm的反应器中，以2000ml/min的曝气量培养6d。重复孵育9次。然后，对生物纤维素的总酵母进行转速和圆盘数量的检查，或pH控制和曝气条件的检查。生物纤维生产反应器最有效的培养条件如下。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量相对于圆盘的转速大致相同，30和50rpm，但在50rpm培养的情况下，生物纤维的一些分散太快而不能保留在圆盘上。因此，最佳转速为30rpm。向气相中充气有助于产生更多的生物纤维素，并有助于提高生物纤维素的物理性能，特别是增加板材的杨氏模数。

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.