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EEG strategy turns Alaskan
town's failing wastewater treatment plant into a super-cleaning
power generator--without costly upgrades and expansion
A year ago, Palmer, Alaska,
faced a problem common to thousands of towns and cities:
Its aging 3-lagoon wastewater treatment plant was failing.
The town braced for an estimated $60 million price tag
for upgrades.
Today, Palmer's treatment plant
is on track to treat more wastewater with less energy--and
even generate power--without expanding the facility's
size or paying staggering upgrade costs. "We're going
to significantly reduce capital costs," says Palmer's
Public Works Director Carter Cole. "But this has
so many other implications. We're taking the waste out
of wastewater."
The town contracted wastewater
system consulting firm, Ecological Engineering Group (EEG)
to design a phased solution that optimizes the existing
lagoons with insulation (phase 1) as well as free waste
heat from a nearby power plant fueled with biogas produced
by the wastewater treatment plant itself (phase 2). The
treatment plant's biodigester will use wastewater combined
with organic and carbon wastes diverted from the landfill
to generate power to fuel the entire plant, reducing the
town's utility rates. Excess power can be sold to the
gas pipeline or the electric power grid.
"The plant will be one
of a few in the country that's energy neutral," Cole
says. These low-cost additions to the plant, funded by
the American Recovery and Reinvestment Act, boost natural
processes to get more effective treatment in a smaller
space, thereby helping the town ward off a utility rate
hike.
"Ecological Engineering
Group is the front-runner in this field," Cole says.
"No other firm came close to meeting our needs. Most
of the other firms wouldn't even consider this. They wanted
to sell us on an expensive new treatment plant."
EEG, he adds, "was the only one that gave us accurate
information about what's going on in the treatment works.
This pushed off a $60 million-dollar improvement cost."
The current 1 million-gallon-per-day
(gpd) plant will increase its capacity to 8 million gpd--a
factor of eight--simply by capturing waste heat discharged
from a power plant and using it to super-charge microbial
activity that treats wastewater faster and produces methane.
This strategy eliminates a common obstacle to biogas production
in cold Alaska: Methane does not form efficiently in cool
places.
EEG calls this patent-pending
approach the Del Porto Q10 System. "Q10" refers
to the principle that warming a biological process by
10 degrees Centrigrade doubles its rate of activity, according
to the system's principal designer David Del Porto. That
means twice the treatment in the same space for every
10-degree C rise in temperature (within limits). For Palmer,
the result is cleaner water discharged to its creek (and
perhaps one day piped for irrigation use), as well as
energy efficiency, power generation, and avoided costs.
"This has larger implications
for cities and the private sector," Cole says. "It
shows that wastewater utilities can be self-sufficient
for costs and energy, and even serve as clean power plants."
With this solution, Cole sees communities and funders
taking a keen interest in infrastructure's potential to
generate significant power, as well as reusable water,
while doubling as water infrastructure and preventing
pollution.
"Ultimately, what we learned
here should go statewide," Cole predicts. "This
approach uses an untapped resource in this country. It's
economically and ecologically sensible."
Canadian
Wastewater Gardens
EEG's Canadian licensee of its
Washwater Gardenª system recently unveiled its first Washwater
Garden. The Big Rideau Lake Association is promoting these
systems, developed by EEG's subsidiary, Sustainable Strategies,
to prevent pollution of the lakeshore by septic systems
and reduce fertilizer use by providing an alternative
way of growing landscapes--with wastewater. EEG provides
engineering of the system. The system debuted at a celebration
attended by residents of the lake's surrounding communities.
Click
here
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Tours
and Workshops
Tours
of ecological wastewater systems in eastern Massachusetts
are periodically conducted by the nonprofit project Ecowaters,
to which EEG provides technical advice.
Tours of the Solar Aquatics system in Weston, Mass. are
conducted regularly for a small honorarium. Contact EEG.
Publications
The New Green
Paradigm, a paper presented at the Onsite and Decentralised
Sewerage and Recycling Conference of the Australian Water
Association, Oct. 15, 2008. [click
here]
EEG
contributes to book
Reusing the Resource:
Adventures in Ecological Wastewater Recycling describes
the form and function of a wide range of ecological wastewater
systems featuring recycling, energy extraction, utilization,
and rootzone-based treatment. More than 50 profiles of
systems worldwide show the viability and favorable economics
of these systems. Order here.
Urban
& Industrial Watersheds
There
is no impending water supply crisis if water is used wisely.
EEG's David Del Porto suggests new ways to view water
planning. Presented at the "Water Crisis: Myth or Reality?"
meeting in Barcelona, Spain in 2004. Download
here
How
can the growing aging population stay independent, both
physically and economically? Read on:
Sustainable
Aging in Place
"Growing
Away Wastewater," an article by Carol Steinfeld and Ecological
Engineering Group's David Del Porto, appeared in the January
2004 edition of Landscape Architecture magazine.
An
updated version appeared in a recent issue of Onsite Water
Treatment magazine:
click here.
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