TY  - BOOK
AU  - Yuthana Tanwongwan
AU  - Samorn Muttamara,
AU  - Lee,Seong-Key
AU  - Umita,Teruyuki
ED  - Royal Thai Government, 
TI  - Sludge bulking and its control in modified A/O processes
PY  - 1994///
CY  - Bangkok
PB  - Asian Institute of Technology
KW  - Sewage
KW  - Purification
KW  - Activated sludge process
N1  - A thesis submitted in partial fulfillment of the requirement for the degree of Master of Science, School of Environment, Resources & Development; Thesis (M. Sc.) - Asian Institute of Technology, 1994
N2  - It is known that A/O process can produce well-settling sludge. But sludge bulking can also  occur in these processes due to some causes such as composition of wastewater, operating  conditions, and, configurations of the systems. From this experiment, it has been observed that  0.2 mIJL of acetic acid can cause zoogloea bulking in A/O processes which had only two  anaerobic tanks but the process that had three anaerobic tanks can control this kind of bulking.  It also has been observed that strictly anaerobic initial contact zone (ICZ) can suppress  filamentous bulking more effective than anoxic one. Furthermore, some of unsuitable operating  conditions , i.e. too low organic loading, too high return sludge ratio, and too long influent  hydraulic retention time can deteriorate sludge settleability and phosphorus removal efficiency but  improve the removal efficiency of nitrogen.  Additionally, it has been found that concept of contact stabilization activated sludge, i.e.  reaeration of return sludge, is difficult to be applied with A/O process because it can introduce  small amount of dissolved oxygen into ICZ so filamentous bacteria can use this 00 as electron  acceptor in their metabolic mechanisms. Floes in units which had reaeration were very small siz.e  and not compact.
UR  - http://203.159.5.9/ait-thesis/detail.php?q=B15803
ER  -