Effects of absorbents on ammonia removal from wastewater through hollow fiber membrane contactor

The aim of this study is mainly to evaluate the effects of absorbents on ammonia removal from wastewater through hollow fiber membrane contactor. There were two absorbents used in the experiments namely sulfuric acid solution and Natural Hot Spring Water (NHSW)-based solution and the pH of absorbents are 2.3 and 0.8. In the ammonia removal experiments, wastewater solution was flowed through the shell side of the contactor, whilst absorbent solution flowed through the lumen side of the fibers. Operating variables such as pH and ammonia initial concentration of wastewater are used as tested variables for evaluating effectiveness of the absorbents. Experimental results show that the ability of NHSW-based solution can compensate the sulfuric acid solution to absorb ammonia through hollow fiber membrane contactor at the same pH of wastewater. The NHSW-based solution give higher ammonia removal efficiency and overall mass transfer coefficient than sulfuric acid solution at ammonia initial concentration of 800 ppm in the ranged pH of wastewater applied in this study. The types of absorbent, at the pH of wastewater of 11, had a negligible effect on ammonia removal efficiency and overall mass transfer coefficient in the range of ammonia initial concentration of 100-800 and 100-400 ppm for the pH of absorbents of 2.3 and 0.8, respectively.