利用聚乳酸作为反硝化固体碳源的研究

利用聚乳酸(PLA)颗粒作为反硝化的固体碳源和生物膜载体,考察了聚乳酸作为反硝化碳源的可行性和温度对聚乳酸颗粒反硝化脱氮性能的影响,并对聚乳酸颗粒表面进行了红外光谱分析和扫描电镜观察.结果表明,PLA颗粒作为反硝化固体碳源和生物膜载体进行反硝化脱氮,接种和驯化时间较长.在30℃,硝酸盐氮初始浓度为50 mg/L时,PLA的平均反硝化速率为2.6×10-3mg/(g.h),13 h内硝酸氮可以完全去除.温度对反硝化速率影响很大,在30~40℃之间反硝化速率较高,一旦偏离适宜温度,反硝化速率降低很快.对PLA颗粒表面的红外光谱分析和扫描电镜观察证实了PLA作为反硝化固体碳源的可行性.PLA颗粒表面的生物膜扫描电镜观察发现生物膜比较薄,以球菌为主.

Denitrification Using Polylactic Acid as Solid Carbon Source

Polylactic acid (PLA) was used as solid carbon source and biofilm support simultaneously, to investigate the applicability of PLA in the denitrification process. The effect of temperature on denitrification performance was also studied. The IR analysis and SEM observation were performed to investigate the PLA surface structure and biofim morphology. The results showed that when the initial concentration of nitrate nitrogen was 50 mg/L and the temperature was 30℃, the average denitrification rate was 2.6 × 10~(-3)mg/(g·h) and nitrate could be completely removed within 13h. Temperature had a significant influence on the denitrification rate. The IR analysis and SEM observation of PLA surface structure confirmed the feasibility of PLA as solid carbon source. The SEM observation of biofim showed that the biofilm was thin and mainly consisted of cocci.