This DWWTP employing activated sludge technology to treat domestic wastewater enriched with food industry wastewater (whey wastewater). The capacity treatment of the  DWWTP is 550 cubic meters per day of domestic wastewater. Nonthereless, inflow organic load was much behind the treatment plant design.

Treatment process:
Raw wastewater drains into an anaerobic pond then follows into the bioreactor (external ring). The bioreactor (V= 350 cubic meter) is well aerated and the mixed liquor flows clockwise and drains into the secondary clarifier (internal ring). The hydraulic retention time (HRT) is approximately 15 hours.  Sludge circulation (RAS – returned activated sludge) persists from the clarifier back into the anoxic pond. Excess sludge (WAS-waste sludge) is removed during the process.

Problem defined:
The biological process suffered from casual stress episodes that were caused by the entry of high organic load resulting in rapid dissolved oxygen reduction. High concentration of organic matter within the wastewater, inducing occasional bio-process treatment oxidative stress episodes thus, reduces the annual treatment yield.

Treatment aim:
To stabilize the biological process in order to improve the effluents quality and annually treatment yield.
Treatment Process Limitation: Dissolved oxygen (blowers capacity limitation).

A significant effluent quality improvement was achieved only in circumstances that the inflow organic matter (BOD), exceed up to 50% above the designed parameters. Meaning that some of the stress episodes were prevented, therefore, annual treatment yield was increases.

SBP technology setup:  

Introdution devices attached to the bioreactor wall.

Upper: A picture of two SBP capsules introduction devices attached to the sanitary wastewater treatment plant bioreactor.
Bottom: Illustarations of bioreactors wall attached SBP capsules introduction devices. Please note that one introduction device is a longer than the other.