| The purpose of this pilot scale study was to demonstrate the potential of using clinoptilolite to remove nitrogen in septic tank effluent by simultaneous nitrification and denitrification. The results of a zeolite system with clinoptilolite in the nitrification zone were compared with a gravel system of same dimensions and operating conditions. Results indicated that the nitrification rate improved by using clinoptilolite, thereby resulting in the improvement of the total nitrogen removal. For a direct loading rate of 306 L/m2/day and a recycle ratio of 6, total nitrogen removal rates of 67% and 60% were achieved in the clinoptilolite and gravel systems, respectively. Clogging occurred in the zeolite system due to disintegration of clinoptilolite, followed by clogging in the denitrification zone, thereby making the system unsuitable for application to real septic tank effluents, with out further development. |
