The overall objective of this project was to identify, review, and select potential filter evaluation methods that are less interruptive than conventional techniques. These condition assessment methods provide information on the overall process performance of a filter and the condition of the granular media.
Three technologies were found to provide meaningful data while reducing the extent of operational interruption during filter evaluations.
The conductivity probe and the fiber optic camera were found to be useful for determining the depth of media layers and the degree of intermixing between media types.
The fiber optic camera also provided a visual inspection of depth of floc penetration into the bed, presence of coatings on the media, and extent of media fluidization and bed expansion during backwashing.
The multi-point head loss probe could be developed as a surrogate for the floc retention profile and for optimizing pre-treatment to achieve greater depth filtration and overall productivity.