Israeli wastewater treatment technology developer, Mapal Green Energy, has
developed a new financial incentive for using its floating fine-bubble diffusers
– where the client pays nothing for the technology and installation, and is only
responsible for sharing profits from electricity-bill savings with the company,
Mapal announced this week.
The first city to implement this technology in
its municipal wastewater plant is Ramat HaSharon, where a pilot phase has been
going on for roughly the past two months, according to Zeev Fisher, Mapal’s vice
president of business development.
“What we have achieved in the last
months is upgrading Ramat Hasharon through an energy-saving-based contract, in
which the municipality or operator who owns the plant does not invest the
money,” Fisher said. “We are making the investment at our expense. We have a
long-term contract with the operator who pays the electricity bill, and we are
sharing the savings.”
“It’s a win-win situation,” he continued. “The
plant is not investing capital, and it is paying less for its
Mapal determines the original conditions of the plant by
gaining access to the client’s old electricity bills and comparing it to the new
ones, and then share the savings.
During wastewater treatment, particles
are first removed through a physical process like simple filtration, and then
dissolved contamination must be somehow removed after – which is done typically
by using natural bacteria to feed on the contaminants, Fisher explained, noting
that in turn, the bacteria need oxygen to survive. The most common method of
doing this in Israel is an archaic method called “surface aeration,” in which
the water is sprayed into the air, where it picks up oxygen and dissolves again,
“This is one of the most significant usage of energy in any
wastewater plant,” agreed Tom Pokorsky, of Wisconsin-based Aquarius
Technologies. “There are very few systems of municipal size that still use that
system because it’s so inefficient.”
Throughout the developed world,
Pokorsky explained, this method is still primarily used in ponds and lagoons –
while most municipal plants have adopted fine-bubble diffusion systems that
spread oxygen from inside the water, and are fixed to the floors of the plants
for maximum surface area.
In Israel, however, most municipal plants still
have the outdated surface aeration system, aside from a couple exceptions,
including Jerusalem, Kfar Saba and Herzliya, Fisher said.
But building an
entirely new structure is costly and difficult, so Mapal has come up with a new
floating, fine-bubble system that can be used in all different types of
locations, as it doesn’t have to be anchored to the ground, Fisher
Instead, the device floats about 15 to 20 centimeters above the
“If a municipality has a wastewater treatment plant with a
concrete reactor, but at present is using surface aeration – floating or fixed
on a concrete bridge – and they would like to upgrade it to fine bubble
aeration, it has two options: drain the reactor completely and build a new one,
or to use our system without stopping the process. [In either of these two
methods] since there are an endless number of bubbles, the surface area is
endless, and there is a very good transfer of oxygen into water,” Fisher
While Pokorsky maintained that the fixed-floor-diffusing system is
still the best in terms of achieving maximum surface area, he said that the
floating system is definitely preferable to the inefficient surface aeration
“There’s no question that device will save money – probably half
the energy compared to surface aerators,” he said, noting that he sees the
system as being particularly beneficial to lagoons and ponds where a system
cannot be anchored to the floor.
As far as municipalities go, should
clients be unhappy with the system, Fisher stressed that Mapal does not remove
the old technology when setting up the new one.
“We are not even taking
the existing aeration system out of the water, so they don’t have any risk
whatsoever,” he said.
“If something goes wrong and our system doesn’t
work – which hasn’t happened – they can always switch back to the old system at
After the current pilot stage is complete – which Fisher said
will be soon – the Ramat HaSharon contract will be negotiated as quickly as
possible, and he hopes that the technology will interest other cities
“All the municipalities can actually save money without
making any investment,” he said.