Removal of As(III), Mn(II) and NH4+-N from synthetic groundwater using biofilm reactor connecting with filtration reactor

Abstract

This research studied the effectiveness of immobilized Bacillus megaterium PNKP-S2 in biofilm reactor connecting with filtration reactor was investigated for removal of sodium-arsenite [(As(III) (40 µg L^-1)]; manganese chloride [Mn(II) (100 µg L^-1)] and ammonium chloride [(NH₄⁺-N) (1000 µg L^-1)] in synthetic groundwater. The results showed that at 25^th day of the operation, the biofilm reactor could removed 85.1 % of As(III) and 56.5 % of NH₄⁺-N and a concentration of nitrate was maximum at 509.4 µg L^-1. Moreover, As(III) and NH₄⁺-N were removed 90.3 % and 65.6 %, respectively and concentration of nitrate was 485.5 µg L^-1. The biofilm reactor could removed 86.6 % of As(III), 41.4 % of Mn(II) and 48.5 % of NH₄⁺-N at 26^th day of operation and the concentration of nitrate was 301.5 µg L^-1. However, 90.5 % of As(III), 59.0 % of Mn(II) and 30.5 % of NH₄⁺-N were removed when the filtration column was connected and the concentration of nitrate was 382.7 µg L^-1. In the end of the experiment (42^th day), the biofilm reactor effectively removed 5.2 % of As(III), 83.5 % of Mn(II) and 85.7 % of NH₄⁺-N. The concentration of nitrate declined to 18.1 µg L^-1. While the filtration reactor totally removed 54.5 % of As(III), 93.6 % of Mn(II) and 89.0 % of NH₄⁺-N). The concentration of nitrate declined to 28.6 µg L^-1. The results indicated that effective removal As(III), Mn(II) and NH₄⁺-N in synthetic groundwater by biofilm reactor connecting with filtration reactor could be achieved and increased in scale for use in the fieldwork for treatment of wastewater in the environment.