Impact of salinity on stabilized leachate treatment from ozonation process

Abstract

Leachate generated from landfill Indonesia is typical has high salinity and organic matters during the dry season, potentially contaminating water and the environment. An increase in salinity might deteriorate the activity of the microorganisms on the decomposition process. This research aims to study the feasibility of the ozonation technique for treating stabilized leachate. The parameters tested were pH, COD, BOD5 BOD5/COD ratio, and TDS. Independent variables of this study were salinity with different concentration from ±0.4 ppt; ±5 ppt; ±10 ppt; and ±20 ppt and ozone contact time up to 60 minutes with an ozone dose of 600 mg/hour. Experimental results revealed that salinity ranging from 0.4 ppt to 20 ppt had little effect on COD removal, and the removal efficiency was around 30%. Further, the ozonation process exhibited better organic removal with an improved BOD5 concentration from 426 mg/L to 887 mg/L in low salinity conditions (0.4 ppt). Meanwhile, it significantly affected the old leachate treatment, where the leachate biodegradability can be enhanced from 0.120 (initial condition) to 0.321 with salt addition of 20 ppt.