000			04195nam a2200409 4500
005			20260817171506.0
008			011298s1998 th r 0000|0 eng d
035			_a.b11733846
099		9	_aAIT Thesis no. EV-98-14
100	1		_aKarn, Sunil Kumar
245	1	0	_aBiological nitrogen removal under inhibitory conditions in a sequencing batch reactor
260			_aBangkok : _bAsian Institute of Technology, _c1998
300			_a113 leaves
490	1		_aThesis ; _vno. EV-98-14
500			_aA thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering, School of Environment, Resources and Development
502			_aThesis (M.Eng.) - Asian Institute of Technology, 1998
520			_aThis study was carried out to investigate the nitrogen removal from wastewater under inhibitory conditions using Sequencing Batch Reactor (SBR). Synthetic wastewater containing aniline was used as feed. A 40-liter laboratory scale SBR was operated with aniline containing synthetic wastewater during the entire investigation. Aniline concentration in the feed was increased gradually from 100 to 450 mg/l while the total cycle time of the SBR was reduced from 12 hours to 8 hours. The cycle time was optimized by reducing the time of react phase of the cycle. Performance of the reactor was observed at different react phases ranging from 9 hours (3 hours aerobic and 6 hours anoxic) to 3.75 hours (1.75 hours aerobic and 2 hours anoxic). The optimal react time was achieved at 4.75 hours (2.25 hours aerobic and 2.5 hours anoxic). At this period, removal of aniline, COD and total nitrogen was observed more than 98%, 95% and 85% respectively for the feed aniline concentrations up to 450 mg/I. The average rate of reaction during aerobic and anoxic phases for aniline biodegradation, nitrification and denitrification were found as 20-40, 2-4 and 1.5-4.0 mg/gVSS/hr respectively. Profiles of pH, DO and ORP during the react phase were successfully simulated to indicate the specific process changes as the start and end of nitrification and denitrification processes. The effect of inhibition due to aniline was observed during the nitrification process. Conversion of NH4 + to N0 2- by Nitrosomonas was not initiated until the concentration of aniline inside the reactor had dropped below 4-5 mg/I. Similarly, conversion ofN02- into N03- by Nitrobacter was inhibited when the concentration of aniline in the feed was reached to about 400 mg/I. Furthermore, as the concentration of aniline in the feed was increased over 450 mg/I, the conversion of N02- into N03- had almost ceased. Nitrobacter activity could not be revived even after aniline concentration in feed was reduced to 300 mg/I. However, there was no significant loss in the total nitrogen removal efficiency of the SBR due to the effects of inhibition as N02- produced by Nitrosomonas could still be denitrified under anoxic condition.
650		0	_aSewage _xPurification _xNitrogen removal
700	1		_aAnnachhatre, Ajit P., _eChairperson
700	1		_aDahl-Madsen, Karl Iver, _eExamination committee
700	1		_aKim Oanh, N. T., _eExamination committee
710	2		_aGovernment of Denmark (DANIDA), _eScholarship donor
810	2		_aAsian Institute of Technology. _tThesis ; _vno. EV-98-14
856			_3Full-Text _uhttp://203.159.5.9/ait-thesis/detail.php?q=B13469
907			_a.b11733846 _bmnait _cy
902			_a240407
998			_b0 _c981201 _dm _ea _fy _g0
945			_lmnait
945			_lmnait
945			_lmnarc
942			_c20
942			_c40
909			_aBarcode : 30050120714430 _bCREATED : 1997-04-07 _cRECORD # : i12110164 _dLPATRON : 1017102 _eLCHKIN : 2005-10-19 _f# RENEWALS : 0 _g# OVERDUE : 0 _hIUSE3 : 0 _iTOT CHKOUT : 11 _jTOT RENEW : 12
909			_aBarcode : 30050120714422 _bCREATED : 1997-04-07 _cRECORD # : i12110176 _dLPATRON : 1017857 _eLCHKIN : 2005-05-30 _f# RENEWALS : 0 _g# OVERDUE : 0 _hIUSE3 : 0 _iTOT CHKOUT : 12 _jTOT RENEW : 8
909			_aBarcode : 30050160077979 _bCREATED : 2016-05-23 _cRECORD # : i12987542 _dLPATRON : 0 _eLCHKIN : - _f# RENEWALS : 0 _g# OVERDUE : 0 _hIUSE3 : 0 _iTOT CHKOUT : 0 _jTOT RENEW : 0
999			_c12425 _d12425