PCL和PU填料用于低C/N值污水处理的对比

Comparison of Polycaprolactone and Polyurethane as Carriers for Treating Low C/N Wastewater

在序批式生物膜反应器中,分别以可生物降解聚己酸内酯(PCL)和可生物降解聚氨酯(PU)为填料,进行了处理低C/N值污水的对比研究。结果表明,在进水C/N值为4.3时,装有PCL填料的1#反应器的启动历时约35 d,而装有PU填料的2#反应器在28 d后即启动成功。最终1#反应器的出水氨氮稳定在4～7 mg/L,2#反应器的出水氨氮稳定在2～5 mg/L。提高进水氮负荷后,1#反应器出水氨氮浓度稳定在18～22 mg/L,2#反应器出水氨氮浓度稳定在6～9 mg/L。1#和2#反应器对总氮的去除率分别约为53.3%和65.3%。通过扫描电子显微镜观察,附着在PU和PCL上的生物膜结构区别很大,PCL上的生物膜以短杆菌和球菌为主,PU上的生物膜则以丝状菌和长杆菌为主。

The treatment efficiencies of low C/N wastewater by using two different materials as car- riers： biodegradable polycaprolactone （PCL） and polyurethane （PU） in sequencing batch biofilm reac- tors （SBBRs） was studied. The results showed that at influent C/N of 4.3, the start-up of the 1# reactor filled with PCL took about 35 d, while the start-up of the 2# reactor filled with PU took about 28 d. Final- ly, the ammonia nitrogen concentrations in the effluents from both reactors stabilized at 4 to 7 mg/L and 2 to 5 mg/L, respectively. After increasing the influent nitrogen load, the ammonia nitrogen concentra- tions in the effluent from both reactors stabilized at 18 to 22 mg/L and 6 to 9 mg/L respectively. The re- moval rates of TN by the two reactors were 53.3% and 65.3%, respectively. Scanning electron micros- copy indicated that the dominant bacteria in the biofilm on the PCL carriers were short rod-shaped and spherical bacteria, while those in the biofilm on the PU carriers were filamentous and long rod-shapedbacteria.