This document discusses the advantages and disadvantages of activated sludge wastewater treatment. The advantages include its ability to remove 97% of suspended solids through biological processes without chemicals, separate solids and liquids, remove organics, and be cost effective to maintain. However, the disadvantages are that cleaning the tanks is troublesome, most plants require at least three tanks, and temperature changes greatly affect the tank.

1. Advantages/Disadvantages
Advantages
Capable of removing97%of suspendedsolids
Biological nitrificationwithoutaddingchemicals
Oxidationandnitrationachieved
Biological phosphorousremoval
Solidsandliquidsseparation
Removesorganics
Cost effective
Easilymaintainedmechanical work
Self sustainingsystem
Disadvantages
Cleaningisahassle
Most plantsneedat leastthree tanks
Temperature changesaffectthe tankgreatly
Activatedsludge isasuspendedprocess,anda suspendedprocessiswhenthe biomassismixedwith
the sewage.The othersecondaryprocessisa fixedfilmprocess.Thisiswhenthe biomassgrowsonthe
mediaandthe sewage passesoverthe surface.Typesof systemsincludeTricklingfiltersandrotating
biological contractors.