Oil and Gas - The Mother of Inflation - GineersNow Petroleum magazine

For the last 100 years, the main practice of
water treatment plant operators to remove
algae from their reservoirs has been the
addition of chemicals. Chemicals that
have been dosed in our waterways may
include copper sulfate or other algaecides
as well as metals (Fe, Cu, Ag, Al, Ca).
Although these methods are considered
as fast working and economical, their
impact on the ecological balance of
a waterbody cannot be disregarded.
Effects of chemical algal control may
include toxicity, lysis of the algal cells and
non-target response, which will lead to a
degradation of the overall quality of the
water.
Based on a European Research project,
LG Sonic has developed a method to
selectively control algae in freshwater
lakes and reservoirs called the MPC-
Buoy (Monitor, Predict, Control). In-situ
monitoring equipment is used to detect
and determine algae species, and
predict blooms based on water quality
parameters. The MPC-Buoy controls
algae by using relatively low power, an
ultrasonic signal that is emitted over the
surface of the reservoir. The ultrasound
of one MPC-Buoy system can cover a
surface area of approximately 50 acres.
Algae rely on their buoyancy to float
close enough to the water surface to
take up sunlight. This allows them to
outcompete other organisms in the water
such as plants, that are also depending
on sunlight intake. The ultrasound used
by the MPC-Buoy systems fixes the algal
cells in a deeper layer of the water column,
preventing them to take up sunlight at the
surface.
Why do we need to use data to
control algae?
Many different algal types can bloom in
a water body. Some of these algae are
plant cells, while others are bacteria.
Algae may vary in size, shape and cell
characteristics. Typically, the type of
algae that blooms depends on water
temperature and sun hours. As a
result, algal types may change several
times during a season. In addition to that,
algae are also highly adaptive. Some algal
types can resist extreme temperatures
or pH values and cope with fluctuations
in these conditions better than other
organisms such as plants. Because of
algae’s adaptability, algae can easily
develop resistance to algaecides and
other treatment methods, including
ultrasound.
LG Sonic has been researching the
effect of ultrasound on specific algal
types, different types of water bodies and
variations in water quality since 2005.
In collaboration with different European
universities, they have created a database
defining optimal ultrasonic parameters for
different algal species and water quality
characteristics. By continuously updating
these ultrasonic parameters, the system
prevents algae from becoming resistant
to ultrasound.
The MPC-Buoy automatically monitors,
analyzes and predicts algal presence
in the waterbody. For the collection of
water quality data, near real-time sensors
are used to measure pH, Chlorophyll a,
Phycocyanin, Turbidity, Dissolved Oxygen,
and optionally nitrogen and phosphorous.
Based on this information, the MPC-Buoy
can determine the presence of different
algal species and forecast algal blooms.
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