Effects of organic carbon on nitrification rate in fixed film biofilters

Although. it has been recognized that the existence of organic matter in a recirculating system tends to reduce the nitrification efficiency of biofilters. quantitative information is still Lacking. In this study, the effect of sucrose carbon on the nitrification rate of biofilters was evaluated under steady-state conditions using a reactor series experimental system. The experiential solution with a carbon/nitrogen ratio of C/N = 1.0 or 2.0 resulted in approximately a 70%, reduction of total ammonia nitrogen removal rate as compared with a solution that has a similar nitrogen level, but without carbon (C:N = 0). The data showed that the nitrification rate decreased with an increase in the organic concentration, but the impact became less pronounced when the carbon concentration became sufficiently high. The results show the benefits of removing organic matter for improving nitrification in recirculating systems. (C) 2001 Elsevier Science B.V. All rights reserved.