Effect of dilution and operating parameters on ammonia removal from scheduled waste landfill leachate in a lab-scale ammonia stripping reactor

• Main Authors: M. L., Nurul Hanira, Che Man, Hasfalina, M., Rashid, Abdullah, Luqman Chuah, Abdullah, A. M.
• Format: Article
• Language: English
• Published: IOP Publishing 2017
• Online Access: http://psasir.upm.edu.my/id/eprint/61562/1/Effect%20of%20dilution%20and%20operating%20parameters%20on%20ammonia%20removal%20from%20scheduled%20waste%20landfill%20leachate%20in%20a%20lab-scale%20ammonia%20stripping%20reactor.pdf; http://psasir.upm.edu.my/id/eprint/61562/; https://iopscience.iop.org/article/10.1088/1757-899X/206/1/012076
• Institution: Universiti Putra Malaysia

A lab-scale ammonia stripping reactor was used to treat raw and diluted (1:1) scheduled waste landfill (SWL) leachate containing ammonia-nitrogen (NH3-N). Operating parameters such as air-liquid ratio, hydrated lime [Ca(OH)2] dosage, types of packing materials and packing heights were investigated with central composite design (CCD) of response surface methodology (RSM) was used to optimize the parameters affecting NH3-N removal from the leachate. The percentage removal on turbidity, colour and phosphate were also evaluated in this study. It was observed that the optimal conditions obtained from desirable response (NH3-N removal) for raw leachate were predicted at air–liquid ratio of 70, Ca(OH)2 dosage of 5 gL-1, packing height of 60 cm and types of packing material was number 3 (nonwoven polyester) while for diluted leachate these were 70, 6 gL-1, 60 cm and Type 3 (nonwoven polyester), respectively. Quadratic RSM predicted the maximum NH3-N removal to be 78% for raw leachate and 81% for diluted leachate at these optimal conditions concurred with the experiment which successfully removed 76% and 80% of NH3-N, respectively. However, higher removal efficiencies of turbidity (97%), colour (88%) and phosphate (93%) was observed in the treatment with diluted leachate compared to raw leachate merely up to 55%, 34% and 49%, respectively. The finding showed that the difference in the removal of NH3-N in diluted and raw SWL leachate was insignificant. However, turbidity, colour and phosphate showed a significant reduction in the diluted leachate during the treatment. The study suggests that the dilution of SWL leachate does not present a significant effect on the removal of ammonia in the stripping reactor.