2016 Volume 14 Issue 5 Pages 303-307
Laboratory-scale experiment was conducted to evaluate ammonia removal from high ammonia-containing wastewater by downflow hanging sponge (DHS) reactor used as ammonia stripping system. Synthetic deproteinized natural rubber wastewater was used for the experiment. The synthetic wastewater contains 0.2% (v/v) of ammonia and 0.1% (w/v) of urea with 10 − 11 of pH. Total volume of the DHS reactor was 5.6 L (1.7 m of height) including 1.4 L of sponge media. The experiment was conducted with 0.8 − 3.3 days of hydraulic retention time (HRT) and at ambient temperature. Based on the results of the experiment, the DHS reactor achieved 60.3% of ammonia removal with 3.3 days of HRT. In the DHS reactor, ammonia concentration and pH decreased from 1,620 to 650 mgN/L and from 10.4 to 8.1, respectively. The decrease of ammonia after 72 cm depth of the reactor was not observed. Furthermore, nitrate was confirmed in the DHS effluent corresponding approximately to 2 − 6% of removed ammonia. Therefore, it is indicated that ammonia stripping by DHS reactor can be applied as pre-treatment system for high ammonia-containing wastewater.
