Premium
Backwash Turbidimeter Lowers Operating Costs
Author(s) -
Boyd Josephine W.
Publication year - 1985
Publication title -
opflow
Language(s) - English
Resource type - Journals
eISSN - 1551-8701
pISSN - 0149-8029
DOI - 10.1002/j.1551-8701.1985.tb00383.x
Subject(s) - backwashing , timer , filter (signal processing) , clarity , consistency (knowledge bases) , environmental science , engineering , computer science , environmental engineering , telecommunications , artificial intelligence , electrical engineering , mechanical engineering , biochemistry , chemistry , wireless , inlet
Most water treatment plant operators monitor filter backwashing visually (eyeballing) or else wash for a predetermined period of time. However, eyeballing lacks consistency because of human errors and differing perceptions about what is clean enough, and preset timers do not account for changes in plant operation. To make matters worse, eyeballers tend to add a minute or two to wash time for insurance, while timer users commonly set timers on the long side to make sure filters come clean under a worst‐case situation. A backwash monitor or backwash turbidimeter minimizes human error and increases filter efficiency by ensuring adequate washing as well as limiting excessive use of finished water. It measures the wide range of turbidities encountered during backwashing and signals as soon as the wash water achieves the desired clarity. If used in an automated system, the backwash turbidimeter monitors backwash water and signals computers or controllers. This article describes the operation of a typical backwash turbidimeter and gives an example of its use in a Forest Grove, Oregon, water treatment plant.