Innovative integrated fixed-film/activated sludge retrofit could save millions
Aerial photo of the Lakeview WWTP, recently re-rated
to 392,000 m3/d capacity.
The Regional Municipality
of Peel has initiated
expansions of its
two wastewater treatment
plants, the 336,000 m3/d
Lakeview WWTP and the
163,500 m3/d Clarkson WWTP,
to provide capacity for significant
growth anticipated in the Region
over the next several years. An
estimated $300 million in capital
works will be constructed by 2006
at these facilities.
The capacity expansions follow
the completion of a comprehensive
Regional Biosolids Management
Strategy, which was initiated
in 2000, and facility planning
studies completed through the
Class Environmental Assessment (EA)
process, started in 2001. In addition, the
Clear Scents odour management strategy,
which included public consultation
and implementation of short-term odour
control measures, was initiated in 2001
to specifically address odours from the
Lakeview WWTP. Odour management
was identified to be a primary goal for
the expanded facilities. The projects and
programs were completed by a team led
by KMK Consultants Limited, and included
Black & Veatch and Hardy
Stevenson Associates Limited.
Public Information Centres for the
Class EA were held in October 2002,
and the environmental planning process
will be completed before the end of this
year. To meet the aggressive time frame,
the preliminary designs for the expansions
were initiated in July 2002, and
the first Value Engineering workshops
on the facilities plans were completed
in the summer of 2002.
Implementation of short-term measures
to control odours from the
Lakeview WWTP also significantly reduced
biosolids processing recycle
streams. This has enabled the Lakeview
WWTP to be re-rated from 336,000 m3/d
to 392,000 m3/d, with a new Certificate
of Approval issued in October 2002.
Additional capacity at the Lakeview
plant is required by 2006. KMK and
Black & Veatch were awarded the $200
million Lakeview WWTP expansion
project, to expand the plant to 448,000
m3/d, the largest project of its kind in
Ontario in many years. The wastewater
treatment plant projects include expansions
and upgrades to headworks, primary
and secondary treatment and disinfection.
The recommended biosolids management
strategy includes decommissioning
of the thermal conditioning
process, identified as the most significant
source of odours at the facility, replacement
with a new centrifuge
dewatering facility, and expansion of the
existing fluidized bed incineration facility.
It is also planned that Clarkson
WWTP biosolids, which are currently
being hauled as a liquid for co-processing
with Lakeview WWTP, be
dewatered at Clarkson and hauled as
cake to Lakeview for incineration. This
will reduce current truck traffic across
Lakeshore Road in Mississauga, between
the two plants, by about 80%.
Following a comprehensive evaluation
of secondary treatment technologies
in the planning process, it was recommended
that a hybrid fixed-film/suspended
growth retrofit to the existing
conventional activated sludge plant be
seriously considered as an approach to
expanding the Lakeview plant's
wastewater treatment capacity, and
meeting the non-acutely lethal effluent
requirements being proposed by the Ontario
Ministry of the Environment
(MOE). This retrofit could save the Region
in the range of $40 to $100 million
in capital costs, depending on the level
of treatment imposed by the MOE.
To evaluate O&M impacts, and determine
site-specific design and operating
parameters, a 14,000 m3/d demonstration
train of the integrated
fixed-film/activated sludge (IFAS)
process, which involves adding
plastic biomass carrier media to
aeration tanks, is being retrofitted,
and will be operated for a one year
period beginning early 2003. The
IFAS technology has been demonstrated
in Ontario, and is operating
or currently being installed
in Christies Beach, Australia,
Broomfield, Colorado, Moorhead,
Minnesota and Peterborough,
Ontario. The full-scale retrofit of
the IFAS technology at the
Lakeview WWTP would be an
order of magnitude larger than any
other facility in the world.
In parallel, the Region of Peel will
be conducting a separate pilot-scale
study to evaluate the performance of the
various IFAS carrier media, so that design
specifications for potential fullscale
implementation can be accurately
defined.
The Region of Peel has received a
$100,000 grant from the Federation of
Canadian Municipalities Green Municipal
Enabling fund for the demonstration
of the innovative IFAS process.
Earth Tech was awarded the Clarkson
WWTP expansion project, which includes
expansion and upgrade of the
headworks, secondary treatment, disinfection
and biosolids management processes.
Deborah Ross, P.Eng. is Associate and
Senior Process Specialist at KMK Consultants
Limited.
William Fernandes, P.Eng. is
Wastewater Program Manager, Region
of Peel.
See our home page on how to order your subscription. We regret we can
only accept orders from Canada and the United States.
