Premium
Biological kinetic behaviors and operational performances in aerated and oxygenated systems
Author(s) -
Yang P. Y.
Publication year - 1977
Publication title -
biotechnology and bioengineering
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.136
H-Index - 189
eISSN - 1097-0290
pISSN - 0006-3592
DOI - 10.1002/bit.260190807
Subject(s) - aeration , dilution , chemistry , effluent , activated sludge , substrate (aquarium) , volume (thermodynamics) , bioreactor , chromatography , chemical oxygen demand , hydraulic retention time , pulp and paper industry , wastewater , environmental engineering , environmental science , thermodynamics , organic chemistry , ecology , physics , biology , engineering
Biological kinetic behaviors of the oxygenated and aerated activated sludge process were studied and compared in both once‐through and constant sludge recycle systems. The models derived by Herbert, Elsworth, and Telling [ J. Gen. Microbiol. , 14 , 601 (1956)] and Ramanathan and Gaudy [ Biotechnol. Bioeng. , 11 , 207 (1969)] were used for the studies of once‐through and constant sludge recycle systems, respectively. Soft drink waste water was used for the growth limiting substrate. Temperature was controlled within 30 ± 2°C. The influent substrate concentration was maintained at 1,000 mg/liter. The experiments were conducted at various dilution rates (from \documentclass{article}\pagestyle{empty}\begin{document}$ \frac{1}{9} $\end{document} to 1/1.0 hr −1 ), and recycle solids concentration values (from 5,000 to 10,000 mg/liter), with hydraulic recycle ratio, α, at 0.3. Biological kinetic constants were evaluated and compared. It was found that these constants were different for the aerated and oxygenated systems within a certain range of dilution rates studied. The critical dilution rates for diluting out effluent chemical oxygen demand (COD) occurred at 0.1 and 0.2 hr −1 in the once‐through operation, and 0.2 and 0.4 hr −1 in the sludge recycle operation for aerated and oxygenated systems, respectively. Observed sludge yield values and specific growth rate were varied with the type of aeration and with and without constant sludge recycle concentration applied. Sludge carbohydrates and proteins content in the oxygenation system (cell recycle) were 10.1–21.6% and 35.6–52.2%. Sludge volume index in the air and oxygenation systems varied from 41.4 to 354 and 31.9 to 58.5, respectively.