改性聚β-羟基丁酸戊酸酯反硝化特性研究

Denitrification Characteristics of Modified PHBV

以NaHCO_3为改性剂,改性聚β-羟基丁酸戊酸酯(PHBV)作为反硝化反应器的外加固体碳源和生物膜载体,反硝化去除水中NO_3^--N。研究NaHCO_3对PHBV原料的影响,以及改性后PHBV填料反应器的反硝化效果。结果表明,NaHCO_3能使PHBV产生多孔结构,提升空隙率1.20～2.06倍。改性PHBV具有活性污泥包容量提高、微生物与固体碳源接触面积增加、降低水流冲击、增加生物膜强度等优点。红外光谱分析显示改性PHBV表面官能团与原料PHBV一致,未产生改变。在PHBV与NaHCO_3质量比为10:0.5时,填料各方面表现为佳。适当的改性能够使PHBV原料产生一次性溶解性有机物(DOM),提高微生物繁殖速率,缩短挂膜时间。在小试反应器中,NO_3^--N去除率至少在95%以上,其他参数未有负面变化。

Removal of NO3--N from water by using modified PHBV as external solid carbon source and biofilm carrier for denitrification reactor, NaHCO3 as the modifier. The effect of NaHCO3 on the PHBV raw material and denitrification effect by modified PHBV filler reactor was analyzed. The results showed that NaHCO3 could improve the porosity 1.20~2.06 times of PHBV and produce porous structure. The modified PHBV had advantages of increased active sludge inclusion capacity, and contact area between microorganisms and solid carbon source, decreased water flow impact and increased biofilm strength. FTIR analysis showed that the surface functional group of modified PHBV was the same as raw PHBV, and its essential characteristics had no change. When the mass ratio of PHBV to NaHCO3 was 10: 0.5, every aspects of the filler had best performance. Appropriate modification could make raw PHBV produce disposable dissolved organic matter(DOM), moreover shorten biofilm culturing time and increase rate of microbial reproduction. In the pilot experimental reactor, NO3--N removal rate was stable above 95%, and there were no negatively changed in the other parameters.