Simultaneous nitrate, nickel ions and phosphorus removal in a bioreactor containing a novel composite material.

ABSTRACT

This study presents the novel composite material TMCC/PAA/SA@Fe(TPSA), a bacteria immobilized carrier for use in bioreactor systems to enhance the simultaneous removal efficiency of nitrate, Ni(II) and phosphorus. The influence of various operational factors were evaluated on the performance of nitrate, phosphorus and Ni(II) removal. Results demonstrate that under optimum conditions of an hydraulic retention time (HRT) of 8 h and pH 7.0, nitrate and phosphorus removal reached nearly 100% and 61.7%, respectively. When the initial Ni(II) concentration was 1 mg/L, approximately 100% Ni(II) removal efficiency was achieved. Furthermore, the morphology and components of the TPSA immobilized bacterial pellets were analyzed to investigate the mechanism of simultaneous nitrate, Ni(II) and phosphorus removal. Microbial metabolism was more active in the experimental reactor compared with control, although high concentrations of Ni(II) could inhibit bacterial activity.