信号分子强化改性挂膜沸石持续抑制沉积物中氨氮释放

为寻找一种长期有效的底泥修复方式,对沸石进行了改性并挂膜的实验.考察了4种铝盐AlCl₃、 Al（NO₃）₃、 Al₂（SO₄）₃和KAl（SO₄）₂]改性挂膜沸石对上覆水中氨氮的去除情况.结果表明,AlCl₃改性挂膜沸石效果最佳,且最佳改性浓度为0.8 mol·L^-1.进一步分析添加信号分子OHHL后,AlCl₃改性挂膜、 NaCl改性挂膜和天然挂膜沸石抑制河流底泥中氮释放的持续性.其中AlCl₃改性挂膜沸石上附着的细菌量多,反硝化菌数量占比高（初始82.1%; 30 d后61.1%）,因此,生物再生率高（64.9%）,从而使得该沸石使用寿命长达8.5个月.可见,AlCl₃改性挂膜沸石能对底泥释放的氮负荷达到有效持续地抑制.

Persistent Inhibition of Ammonium Released from Contaminated Sediments Through a Modified Zeolite and Biofilm System Enhanced by Signaling Molecules

This experiment used a modified zeolite and biofilm system to find a long-term effective way of repairing sediment. Four types of modified zeolitesAlCl₃, Al(NO₃)₃, Al₂(SO₄)₃, and KAl(SO₄)₂] and a biofilm system were investigated for the removal of ammonia nitrogen from overlaying water. The results showed that, of the modified zeolites, AlCl₃ had the greatest effect on the zeolite and biofilm system, and the optimal modified concentration was 0.8 mol·L^-1. The persistence was further studied after adding OHHL, including the inhibition of ammonium released from contaminated sediment by the AlCl₃-modified zeolite and biofilm system, NaCl-modified zeolite and biofilm system, and natural zeolite and biofilm system. The results illuminated that the number of bacteria attached to the AlCl₃-modified zeolite and biofilm system was the highest, and the proportion of denitrifying bacteria was also high (the initial proportion was 82.1%; 30 days later it was 61.1%). Therefore, the biological regeneration was high (64.9%), which caused the zeolite service life to be up to 8.5 months. Thus, ammonium released from contaminated sediment can be inhibited effectively and continuously by an AlCl₃-modified zeolite and biofilm system.