玉米芯固定化产碱杆菌DN25处理含氰废水研究

目的]研究使用玉米芯作为固定化载体处理氰化物。方法]以玉米芯为载体,对一株产碱杆菌DN25进行固定化,以实验室配制的模拟含氰废水为底物进行降解试验。结果]采用菌体附着载体生长的方式来制备固定化细胞,最佳培养条件为温度30℃,pH8.0。固定化细胞对50 mg/L含氰废水45 m in的降解率为98.5%,对300 mg/L含氰废水降解率可达91.9%。批式重复使用固定化细胞进行降解,前5次对氰化物的降解率仍可维持在80%以上。所设计的固定床反应器中系统运行稳定,固定化细胞降解效果良好,连续运行25 d,前15 d对于氰化物的最大降解率高达99.25%。结论]与其他传统载体相比,玉米芯为天然绿色植物,廉价易得,可降解,本身不会对环境造成二次污染,且玉米芯多孔、吸附能力强、固定化效果好。

Biodegradation of Cyanide by Immobilized Alcaligenes sp.DN25 Corncob as the Carrier

Objective]The aim was to study biodegradation of cyanide by immobilized Alcaligenes sp.DN25 corncob as the carrier.Method]The treatment of cyanide-containing wastewater by the immobilized Alcaligenes sp.DN25 with the corncob as carrier was studied.Result]The immobilization could be realized through the growth of the cell on the corncob during the culture process and the optimal culture condition was found to be 30 ℃,pH 8.0.The degradation rate of 50 mg/L cyanide by the immobilized cell might achieve 98.5% at 45 min,while the conversion of 91.9% achieved for 300 mg/L.The degradation of cyanide by the corncob-immobilized cell was carried out in the batch.The immobilized cell could be used repeated and the degradation rate of cyanide could maintain above 80% during the first five circle.When the immobilized cell was employed in a continuous-bioreactor for 25 days,it showed a good operation stability and degradation ability.The highest degradation rate could reach 99.25% during the first fifteen days.Conclusion]Compared with other traditional carrier,corncob,a natural green plant,was biodegradable,low cost and will not become pollution sources and moreover,it was of plenty holes and stong absorbility,thus possibly becoming a good immobilization carrier.