环境因素对六氯苯厌氧降解活性的影响

在厌氧污泥具备了较好的六氯苯（HCB）降解能力的基础上,采用标准血清瓶实验方法考察了反应温度、初始pH、摇床转速和营养元素等环境因素对厌氧污泥降解HCB活性的影响。实验设计的反应温度为25、30、35和40℃;初始pH为5.0、6.0、7.0和8.0;摇床转速为0和150r·min-1;营养元素有葡萄糖和维生素b12。用HCB浓度随时间的减少来表征微生物对其的降解活性。结果表明,反应温度对HCB的降解速率有很大影响,适宜温度为35℃左右。初始pH对HCB降解活性没有显著影响,但显示出有随初始pH增大而HCB降解活性增加的趋势。与静置条件相比,一定的混合作用有利于提高HCB的降解活性。有葡萄糖存在条件下,维生素b12对HCB的降解活性有明显的促进作用。温度及外加碳源（葡萄糖）是影响HCB厌氧降解活性的重要因素,并推测葡萄糖在HCB降解过程中提供电子供体方面发挥了重要作用。

Impact of environmental factors on the anaerobic degradation capability of hexachlorobenzene

Base on the anaerobic sludge with preferable degradation ability for HCB, we studied the effects of a variety of environmental factors （reaction temperature, initial PH, speed of shake vainer, nutrition） on the degradation activity of anaerobic sludge. Experimental conditions were set as follows： temperature at 25, 30, 35, 40℃, pH at 5.0, 6.0, 7.0, 8.0, speed of shake vainer at 0 and 150 r＇min^-1, nutrition element was glucose and vitamin b12. The degradation rate of HCB was represented by its concentration as time going by. Results show that temperature has significant effects on the degradation rate and the optimum reaction temperature is 35 ℃ Though initial pH has no remarkable impact on the HCB degradation capability, however, HCB degradation capability can be strengthened a little with the increase of the initial pH. Compared with static condition, suitable shaker is helpful to improve HCB＇s anaerobic degradation capability. In addition, vitamin b12 accelerated HCB degradation greatly. Temperature and supplemented carbon source （glucose） are important to the anaerobic degradation of HCB.