Krongtong Sripruitkait creator Annachhatre, Ajit P. Chairperson Takizawa, Satoshi Examination committee Eckhardt, Ing Heinz Examination committee Asian Institute of Technology Partial Scholarship Scholarship donor text th Bangkok Asian Institute of Technology 1998 monographic eng 123 leaves Denitrification with using aniline as a carbon source was investigated in the upflow denitrification reactor. Synthetic wastewater comprising of N03-N, aniline and nutrients was used as feed. Investigations were carried out to ascertain the effect of upflow velocity, N03-N load and N03-N concentration on denitrification rate with aniline as a carbon source. A 2.8 L upflow denitrification reactor was operated at ambient temperature of about 28-32°C and maintained ML VSS of about 10,000-11,000 mg/L. The results obtained indicated that aniline could be successfully used as a carbon source by denitrifiers. Aniline required for denitrification was estimated as 1.1 g aniline/g N03-N. The denitrification rates achieved were about 70 to 90 mg N03-N/L·d based on volumetric load and were about 9 to 12 mg N03-N/g MLVSS·d based on sludge load. The experiments also showed that denitrification rate is affected due to upflow velocity, influent N03-N load and N03-N concentration. At constant influent N03-N concentration of about 90-95 mg/L, upflow velocity between 3 to 4 cm/hr was found to be optimum for achieving denitrification rate of about 90 mg N03-N/L·d based on volumetric load and about 12 mg N03-N/g MLVSS·d based on sludge load. Increase in upflow velocity to 5 cm/hr resulted in reduced denitrification rate. Maximum denitrification rate of about 90 mg N03-N/L'd based on volumetric load and about 12 mg N03-N/g MLVSS·d based on sludge load was achieved for upflow velocity of 3 cm/hr at the N03-N loading of about 95 mg N03-N/L·d based on volumetric load and about 13 mg N03-N/g ML VSS·d based on sludge load. At constant upflow velocity of 4 cm/hr, the maximum denitrification rate of about 85 mg N03-N/L·d based on volumetric load and about 12 mg N03-N/g MLVSS·d based on sludge load were achieved at influent N03-N concentration between 70 to 90 mg/L. A thesis submitted in partial fulfillment of the requirement for the degree of Master of Engineering, School of Environment, Resources and Development Thesis (M.Eng.) - Asian Institute of Technology, 1998 Sewage Purification Nitrogen removal Asian Institute of Technology. http://203.159.5.9/ait-thesis/detail.php?q=B12739 http://203.159.5.9/ait-thesis/detail.php?q=B12739 011298 20260818090024.0