Intensive Nitrification Process Employing Immobilized Nitrifiers on Polyester Carriers in Closed-System Aquaria

Abstract

Freshwater autotrophic nitrifying bacteria cultivated and fixed on polyester tablets were used as concentrated nitrifiers for rapid start-up of ammonia and nitrite removal in closed-system aquaria. Study on the present process has led to the following conclusions. In wastewater with blank carriers, the carriers acted as supporting media for immobilizing the intrinsic nitrifiers which were able to accelerate moderately the natural nitrification. The natural nitrification, however, showed moderate ammonianitrite
transformation, but non-significant nitrite-nitrate transformation. The present intensive artificial nitrification process could remove rapidly the ammonia and nitrite to nearly 100 per cent starting from the beginning and continued throughout 40 days experiment. It could rapidly accomplish the ammonianitrite-nitrate nitrifying process successfully. The inexpensive materials used and the simple method so developed has made this a cost effective nitrogenous toxic compounds removal process which is very important for wastewater treatment as well as in the aquaculture.