Integrating high-rate DAF technology into plant design

Compared with sedimentation, dissolved-air flotation (DAF) is a more efficient clarification process for separating floc particles, which are often low in density. This article investigates the use of short flocculation times with high DAF and filter hydraulic loading rates and examines the feasibil...

Full description

Saved in:
Bibliographic Details
Published in:Journal - American Water Works Association 1999-12, Vol.91 (12), p.41-53
Main Authors: Edzwald, James K., Tobiason, John E., Amato, Tony, Maggi, Lawrence J.
Format: Article
Language:English
Subjects:
Applied sciences
Bubbles
Clarification
Cold water
Design
Disinfection & disinfectants
Dissolved Air Flotation
Drinking water and swimming-pool water. Desalination
Exact sciences and technology
Experiments
Flocculation
Hydraulics
Loading
Loading rate
Onsite
Pilot Plants
Pilot projects
Pollution
Pretreatment
Sedimentation & deposition
Supplies
Surface water
Temperature
Turbidity
Water filtration
Water quality
Water temperature
Water treatment
Water treatment and pollution
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Compared with sedimentation, dissolved-air flotation (DAF) is a more efficient clarification process for separating floc particles, which are often low in density. This article investigates the use of short flocculation times with high DAF and filter hydraulic loading rates and examines the feasibility of integrating high-rate DAF technology into water facility design. Research was conducted at pilot scale using two water sources of varying quality. Numerous runs were carried out under extremely conservative cold water conditions of 3-5°C. The most important research finding is that integration of high-rate DAF treatment technology is feasible. DAF treatment facilities may be designed and operated with flocculation times of 5 min, DAF hydraulic loading rates of 30-40 m/h (12-16 gpm/sq ft) depending on water temperature, and high filtration rates of 20 m/h (8 gpm/sq ft). At higher DAF loading rates, excess air bubbles can be eliminated by internal or external air removal methods.
ISSN:0003-150X
1551-8833
DOI:10.1002/j.1551-8833.1999.tb08749.x