Ammonia nitrogen (NH3 + NH4+) removal using aeration of Submerged Aerated Filters (SAF): PRESENTAION ONLY
Baird, A.1 and Lawrence, A.2, 1 WPL Ltd, 2University of Portsmouth, UK
(free)
Using process control SAF can be effectively manipulated to remove nutrients biologically. SAF traditionally is viewed as a high cost process due to energy consumption in providing high volumes of air.
Without adequate oxygen, bacteria in the wastewater breaks down odour free compounds to odorous compounds: fats and carbohydrates convert to alcohols, esters, aldehydes and carboxylic acids while proteins go to ammonia, amides and hydrogen sulphide.
Excessive or inadequate aeration can lead to operational problems for the treatment process. Inadequate aeration during high loading can cause ineffective treatment of ammonia, while excessive aeration may lead to a high sludge volume index (SVI) resulting from biofilm and floc breakup.
This paper explores SAF process optimisation with the air and power associated with ammonia removal.
Variation in aeration rates alters hydraulic flow and oxygen transfer efficiency through direct contact with the biofilm and dissolution into the liquid. Varying the aeration rate effects oxygen transfer, flow conditions and shear. Biofilm formation is primarily dependent on the interaction between mass transport and the conversion process, the basis of this data was formed through a PhD study undertaken at Petersfield WWTW.
