UASB AerationFundamentals



Aeration Fundamentals


Need to know more? Send us an email or feel free to search our online series with our give away search engine:



    Aerobic treatment such as activated sludge and aerated lagoon applications is by far the greatest application of aeration equipment.  Aeration is also used in water treatment operations for chemical oxidation of inorganic constituents such as iron, manganese and hydrogen sulfide.  It is also used for odor control and/or oxygen content restoration.

   Suspended growth or activated sludge systems typically consist of some type of pretreatment followed by an aeration basin and a final solids separation unit.  The purpose of pretreatment is to remove large suspended solids than can interfere with the mechanical features in biological treatment equipment or to reduce the organic load reaching the aeration basin.  To a certain extent this arrangement may be the simplest configuration, i.e. a single-sludge design.  

     Numerous variations have been used for treating industrial as well as municipal wastewaters.  Such variations include two stage activated sludge systems, combinations of fixed-film and suspended-growth systems, fluidized-bed reactors and membrane bioreactors.  Other activated sludge arrangements basically do away with primary clarification and handle the load almost entirely.

     Most types and brands are suitable for activated sludge applications, but each has its own best applications. For example, brush aerators are best for oxidation ditches while fixed diffusers and surface aerators are best for conventional AS systems. The key is to size the unit properly for each application.  Once OTR characteristics are established, the sizing is fairly straightforward. Other factors include alpha factor, impact of floc size and settleability, impact on effluent TSS, etc. The key phrase is "if properly sized/selected."



Need Some Help? - James C. Young Environmental - Balestie, Irwin & Balestie