Abstract: As alkaline pH regulators,sodium hydroxide and calcium hydroxide are widely applied in fermentation industry. In the fermentation process,these two pH regulators produce organic acid salts with significantly different solubility,which can indirectly affect the fermentation process. This study focused on investigating the effects of two alkaline pH regulators on the 1,3-propanediol fermentation process. Through laboratory investigations on the process parameters (including osmotic pressure of the fermentation liquor,composition of tail gas,fermentation period and production intensity),the negative effect of using soluble strong alkali as pH regulator in 1,3-propanediol fermentation has been analyzed. The feasibility of interval anaerobic fermentation has also been examined using sodium hydroxide as pH regulator,and the fermentation grows into its end stage after about 21 hours within one period. So,the active stage of fermentation is relatively short,and shortening the fermentation period should be helpful to raise the production intensity. In addition,by ventilation during the interval anaerobic fermentation,the use of nitrogen can be further reduced to improve the economical efficiency of this process.

Key words: 1,3-propanediol, pH regulator, fermentation, anaerobic

摘要： 氢氧化钠、氢氧化钙作为碱性pH调节剂，被广泛应用于发酵行业。两种pH调节剂在发酵过程中形成的有机酸盐，其溶解性存在显著差异，从而间接影响发酵过程。本文重点考察了两种碱性pH调节剂对1,3-丙二醇发酵过程的影响，通过发酵液渗透压、尾气组成、发酵周期、生产强度等过程参数的试验考察，分析了可溶性强碱作为pH调节剂不利于1,3-丙二醇发酵的原因，并且在以氢氧化钠作为pH调节剂的发酵体系中，考察了区间厌氧发酵方案的可行性。从氢氧化钠pH调控下的发酵周期来看，约21h后转入发酵末期，发酵活跃期相对较短，因此缩短发酵周期，有利于提高平均生产强度。另外，通过区间厌氧通气方案，能够进一步减少氮气使用量，提高该工艺的经济性。

关键词: 1,3-丙二醇, pH调节剂, 发酵, 厌氧