利用磁性固定化微生物降解水中微量油

Degradation of trace oil in water using magnetic immobilized microorganism

炼油循环水用量大且含有烃类等难降解有机物,因此需要探索高效、经济、环保的水处理技术。文中利用聚乙烯醇-海藻酸钠-Fe_3O_4粒子复合物包埋微生物,控制Fe_3O_4粒子质量分数为14.9%,磁性固定化微生物饱和磁化强度为8.59 emu/g,处理含柴油质量浓度60 mg/L模拟水,30℃反应72 h,降解率达到99%以上。而在相同条件下,游离微生物对水中微量油的降解率为86.8%,磁性固定化微生物经水中柴油驯化后,活性、耐酸碱和耐底物高浓度进一步提高,处理含柴油质量浓度60 mg/L模拟水,反应40 h降解率达到99%,并且处理640 mg/L,高质量浓度含油水降解率达95%以上。使用13次循环处理60 mg/L含油水,反应40 h的降解率均达95%以上,表明磁性固定化微生物具有优异的重复使用性。

Because of the large consumption of refinery circulating water and it containing refractory hydrocarbons, it is essential to explore an efficient, economic and eco-friendly treatment of waster water. The immobilized microorganisms was prepared from PVA and SA with Fe3O4 particles mass fraction of 14.9% . The saturation magnetization was 8.59 emu/g. The biodegradation conditions for trace diesel in water （60 mg/L） were listed as the following： the temperature was 30 ℃, and the biodegradation time was 72 h. After treatment with the immobilized microorganisms, the degradation rate of diesel was above 99%. While do the analogy experiment with the free microorganisms, the degradation rate of diesel was only 86. 8%. Activation of the immobilized microorganisms with oil would lead to higher reactivity, resistance ability to acid and base, and high concentration of substrate. Treatment of diesel solution with 60 mg/L with the activated biocatalyst for 40 h, the degradation rate of diesel was 99%. For the degradation of diesel solution with 640 mg/L, the degradation rate of diesel was more than 95%. After biodegradation for 13 times, the immobilized microorganisms remained reactivity, resulting in the degradation rate of diesel over 95%.