Respiration rate of sludge
The respiration rate for ammonium (AUR) may be used to evaluate the amount of
nitrifying bacteria (autotrophic bacteria) /16 I.
Example 2.4
The respiration rate in an activated sludge sample has been measured at 32 g 0 2/(kg
VSS · h) and 7 g N03-N/(kg VSS · h), respectively. Find the fraction of denitrifying bacteria, Tlg·
32 g 0 2/(kg VSS · h) corresponds to (32 g 0 2/32 g 0 2) · 4 e eqv = 4 e eqv/(kg VSS ·
h). It is a good respiration rate which indicates that the sludge is active, and that organic matter is available as a substrate.
7 g N03-N/(kg VSS ·h) corresponds to (7 g N03-N/(14 gN03-N) · 5 e eqv = 2.5 e
eqv/(kg VSS · h).
7 g N/(g VSS · h) is a high denitrification rate. A good, easily degradable carbon source must be available.
Tlg = 2.5/4 = 0.63
This is a normal fraction of denitrifying organisms.
References
/1/ APHE (1985): Standard Methods for the Examination of Water and Wastewater. 16th edition. American Public Health Association, Washington D.C.
/2/ VCH (1989): Deutsche Einheitsverfahren zur Wasser-, Abwasser- und
Schlamm-Untersuchung Bd. I-III (German Standard Procedures for the Examination of Water, Wastewaters and Sludge, Volumes I-III). VCH Verlagsgesellschaft, Weinheim.
/3/ Danske standarder for analysemetoder for vand (Danish Standards for
Methods of Analysis for Water). Danish Standards Association, Copenhagen.
/4/ DS 207 (1985): Vandunders¢gelse. Suspenderet stof og gkderest (Total Non
Filtrable Residue and Fixed Matter in Non Filtrable Residue). Danish Standards Association, Copenhagen.
/5/ Popel, F. (editor) (1975/88): Lehrbuch fur Abwassertechnik und Gewasserschutz (Textbook for Wastewater Engineering and Protection of Aquatic
Environment). Deutcher Fachschriften-Verlag, Wiesbaden.
I 6/ Institut fur Wasserversorgung, Abwasserreinigung und Gewasserschutz der
Technischen Hochschule Wien (1972): Klaranlage Wien-Inzersdorf, Blumental. Betriebsbericht fur den Zeitraum Oktober 1969-0ktober 1972 {Institute
for Water Supply, Wastewater Treatment and Protection of Aquatic Environment, Vienna Technical University (1972): Treatment plant Wien-Inzersdorf,
Blumental. Report on the operation for the period October 1969 to October
1972).
52
The respiration rate for ammonium (AUR) may be used to evaluate the amount of
nitrifying bacteria (autotrophic bacteria) /16 I.
Example 2.4
The respiration rate in an activated sludge sample has been measured at 32 g 0 2/(kg
VSS · h) and 7 g N03-N/(kg VSS · h), respectively. Find the fraction of denitrifying bacteria, Tlg·
32 g 0 2/(kg VSS · h) corresponds to (32 g 0 2/32 g 0 2) · 4 e eqv = 4 e eqv/(kg VSS ·
h). It is a good respiration rate which indicates that the sludge is active, and that organic matter is available as a substrate.
7 g N03-N/(kg VSS ·h) corresponds to (7 g N03-N/(14 gN03-N) · 5 e eqv = 2.5 e
eqv/(kg VSS · h).
7 g N/(g VSS · h) is a high denitrification rate. A good, easily degradable carbon source must be available.
Tlg = 2.5/4 = 0.63
This is a normal fraction of denitrifying organisms.
References
/1/ APHE (1985): Standard Methods for the Examination of Water and Wastewater. 16th edition. American Public Health Association, Washington D.C.
/2/ VCH (1989): Deutsche Einheitsverfahren zur Wasser-, Abwasser- und
Schlamm-Untersuchung Bd. I-III (German Standard Procedures for the Examination of Water, Wastewaters and Sludge, Volumes I-III). VCH Verlagsgesellschaft, Weinheim.
/3/ Danske standarder for analysemetoder for vand (Danish Standards for
Methods of Analysis for Water). Danish Standards Association, Copenhagen.
/4/ DS 207 (1985): Vandunders¢gelse. Suspenderet stof og gkderest (Total Non
Filtrable Residue and Fixed Matter in Non Filtrable Residue). Danish Standards Association, Copenhagen.
/5/ Popel, F. (editor) (1975/88): Lehrbuch fur Abwassertechnik und Gewasserschutz (Textbook for Wastewater Engineering and Protection of Aquatic
Environment). Deutcher Fachschriften-Verlag, Wiesbaden.
I 6/ Institut fur Wasserversorgung, Abwasserreinigung und Gewasserschutz der
Technischen Hochschule Wien (1972): Klaranlage Wien-Inzersdorf, Blumental. Betriebsbericht fur den Zeitraum Oktober 1969-0ktober 1972 {Institute
for Water Supply, Wastewater Treatment and Protection of Aquatic Environment, Vienna Technical University (1972): Treatment plant Wien-Inzersdorf,
Blumental. Report on the operation for the period October 1969 to October
1972).
52