2020 Pre-Seminar Workshop #3 - Granular Media Filtration is a Batch Process: Comparison of Various Backwash Procedures and the Effect on Filter Performance


0.3 CEUs


The workshop will begin with a discussion of the granular media filtration process and why it should be considered a ‘batch process’.
Following this, case studies will be presented that compare backwash procedures used in various types of water treatment plants. Case studies for both gravity and pressure filters will be included.
The backwash steps discussed will include:
• Filter drain-down
• Air scour, including rates and duration
• Low-rate and high-rate backwash, including flow rate and duration
• Filter media re-stratification
The workshop will provide Operators with answers to the following questions:
• What is the relationship between poor filter performance and backwash?
• How long does it take to see the effect of a poor backwash program on filter performance?
• How long does it take to see the effect of changes made to the backwash program on filter performance?
• How can the backwash procedure contribute to filter media loss?
• Which backwash procedure is the best?
• Which backwash parameters and data should the Operator be monitoring, trending and collecting?
The workshop will also discuss:
• Stand-alone air scour and backwash vs. concurrent air-water wash: Which is better?
• Backwash turbidity profile: What does it tell us? What doesn’t it tell us?
• Monitoring and trending of backwash pressure: Why is it a critical part of filter operation?

Presented by David and Brett Hambley, AWI

Dates & Locations

    • Session #3
    • Mar 9, 2020 1:00pm - Mar 9, 2020 4:30pm
    • Banff Rocky Mountain Resort - 1029 Banff Ave - Banff

Delivery Formats

Pre-Seminar Workshop