三种因素对海水生物流化床启动期间营养盐去除及amoA基因表达的影响

在实验室规模下,以旋转式生物流化床(CB-FSB)为研究对象,研究了初始总氨氮(TAN)、水温及滤料膨胀率3种条件下,海水生物流化床生物过滤功能启动期间TAN和亚硝酸盐氮(NO-2-N)去除及amoA基因数量的变化。结果显示:生物流化床生物过滤功能启动所需时间随着水温的升高而缩短,在水温为15℃、20℃和25℃时,启动所需时间分别为27 d、25 d和23 d;初始TAN质量浓度的升高也会缩短生物流化床生物过滤功能启动所需要的时间,在初始TAN质量浓度为1 mg/L、2 mg/L、4 mg/L时,启动所需时间分别为24 d、22 d和21 d;在膨胀率为100%和150%时,启动所需时间无明显差别,分别为21 d和20 d,明显好于膨胀率为50%时启动所需时间27 d;amoA基因的数量变化与TAN去除率的变化有一定的相关性,并随着初始TAN浓度的升高而增多,在4 mg/L时数量最多,达到2.76×10~7copies/g。

Effect of the three factors on nutrient removal and expression of amo A gene during the start-up period of seawater cyclo-bio fluidized sand biofilters

Under laboratory scale, with the cyclo-bio fluidized sand biofilter ( CB-FSB ) as the research object,the changes of the removal performance of ammonia-nitrogen and the nitrite-nitrogen,and the amount of amoA gene during the start-up period of cyclo-bio fluidized sand biofilter ( CB-FSB) under different initial ammonia-nitrogen concentrations,water temperatures and filter expansion rates were studied in this paper. The experimental results showed that the time required for the start-up of cyclo-bio fluidized sand biofilter ( CB-FSB) was shortened with the increasing of water temperature. The time required for the start-up of CB-FSB were 27,25,and 23 days at 15℃,20℃ and 25℃,respectively. The time required for the start-up of CB-FSB was shortened with the increasing of the initial ammonia nitrogen concentration. The time required for the start-up of CB-FSB were 24,22,21 days at 1 mg/L,2 mg/L and 4 mg/L,respectively. There was no significant difference between 100% and 150% filter expansion rates for the start-up of CB-FSB,which was 21 days and 20 days,respectively. They were better than that with 50% expansion rate. The time required for the start-up of CB-FSB with 50% expansion rate was 27 days. The amount of amoA gene was related to the change of nitrite-nitrogen removal rate and increased with the increasing of initial ammonia-nitrogen concentration. The amount of amoA gene reached the peak at 4mg/L of ammonia-nitrogen concentration,which was 2. 76 × 107 copies/g.