WASTEWATER
By Rick Lallish
When using sand beds to dry biosolids, what is the probable cause of excessive odor when the material is applied, and what is the best solution?
A. Clogged wedge wires in underdrain, high pressure spray at discharge pointB. Over-digested biosolids, change the digester temperature settingsC. Inadequate digestion, correct the digestion problemD. Inadequate polymer mixing, allow more mixing before biosolids application
ANSWER: C. When operating a drying bed, proper digestion is very important before the material is applied. Inadequately digested biosolids will have offensive odors and will attract vectors, such as flies. Properly digested biosolids should have little to no odors
