The City of Winnipeg completed an intensive Phase 2 pilot water treatment program in
1997. The Phase 2 program tested the most suitable treatment processes for Winnipeg's
water quality on an annual cycle and resulted in a recommendation for a baseline water
treatment process, which included conventional dissolved air flotation (DAF).
In November 2002, the use of high-rate DAF was identified as a potential cost savings
alternative for consideration by the City. In 2003, the City contracted a consultant team
from Earth Tech and CH2M HILL to determine the suitability and limits of the high-rate
DAF process through pilot testing. The high-rate DAF pilot tests were completed in
December 2003 and the suitability of high-rate DAF was determined by comparing the
process performance with data from the Phase 2 testing. Based on the success of the
high-rate DAF pilot trials, it was recommended that high-rate DAF be considered as a
viable alternative to conventional DAF for the City's full scale Water Treatment Plant.
In August 2004, the City contracted the consultant team to design the full scale water
treatment plant. The new treatment plant will use a multiple barrier approach that will
further protect the public from waterborne diseases, improve the aesthetic quality of the
water and help it comply with current and anticipated Canadian Drinking Water Quality
Guidelines and Provincial standards and regulations. High-rate DAF is a relatively new
technology and there is currently only one manufacturer with significant full scale North
American experience (Infilco-Degremont's AquaDAF™ system). Only four full scale
AquaDAF™ systems existed worldwide at the time of the pilot testing. The AquaDAF™
design is patented, and thus the full scale equipment procurement method represents a
key component of the full scale design. A competitive tendering process between
conventional and high-rate DAF incorporating detailed facility life cycle costing, as well
as non-economic evaluation criteria, was selected.
Full scale DAF design optimization includes the flocculation time and mixing energies,
flocculation aid chemical requirements, DAF design loading rate, mechanical float
removal, DAF saturator design, recycle requirements, and the number and size of DAF
basins. The design plant flow is 400 ML/day, which will represent the largest DAF
system in North America. If high-rate DAF is selected, the high-rate DAF design will
represent the highest DAF loading rate (36 m/hr in warm water conditions) among
existing full scale installations. The City of Winnipeg Water Treatment Plant is scheduled
to be constructed and in operation by the end of 2007. Includes 2 references, tables, figures.
| Edition : | Vol. - No. |
| File Size : | 1
file
, 400 KB |
| Note : | This product is unavailable in Ukraine, Russia, Belarus |
| Number of Pages : | 12 |
| Published : | 06/17/2005 |
