It isn't easy being green. - Kermit the Frog
Algae Blooms - Threat and Solution
Due to various factors, RESTCo sees the accelerating growth of algae blooms as a risk to
remote communities in terms of access to drinking water, food production, climate change, employment and possibly
even export income.
In our search for a solution, we have established connections with several other companies, including
Extreme Spill Technology (EST) and an experienced boat
designer / builder to come up with an effective solution for harvesting and removing algae blooms.
EST spill pickup technology was originally designed for oil spill response on large bodies of water -
before the oil hits shore. The technology has been shown to pick up more than 93% of oil it encounters on
the surface of calm water, and can also operate effectively in moderate seas. This patented technology
won international awards and been sold to the Canadian federal government (Canadian Coast Guard),
who stated "the [EST] skimmer is an essential piece of response equipment that we maintain in Atlantic
Canada". The same technology has proven effective at picking up cut aquatic weeds, because it will pick
up anything that floats on water and which is smaller than the trash gate openings in the vessel hull - such as algae.
View EST Algae video
shows model picking up aquatic weeds (58 MB, run-time 6 minutes)
(some information in Chinese - originally for China algae clean-up market)
Our small algae harvesting vessel boasts several unique and valuable features.
Because the EST collection system can pick up the thin layer of near-liquid algae floating on
the surface effectively, it presents a major advantage over existing technology - we don't have to wait
until the algae thickens into a mat to be able to remove it. This means we can attack and remove the
bloom early, before it depletes the oxygen in the water column. As a result, the impact on aquatic
plant and animal life is almost eliminated, and the algae can be harvested for aerobic composting,
greatly reducing CO2e emissions.
The electric drive system does not pollute the environment where it is operating.
The paddle wheel system ‘steps over’ aquatic weeds and other marine life leaving them intact while
harvesting the algae. By having paddle wheels on either side, the boat is highly manoeuvrable for effective
operation in confined spaces (e.g., marinas, canals, harbours).
Not using a propeller for pickup operation increases effective operating time, as propellers are easily
and quickly fouled in an environment characterized by heavy algae and aquatic weeds.
For operations in relatively calm waters, "Y" gates can be added to the front of the 2 hulls,
increasing the effective sweep area of the vessel, and clearing the surface ahead of the paddle-wheels.
The operator never needs to come in contact with the algae, which is important as some algae types
contain toxins. The algae is channelled below the vessel, picked up via gravity in the EST collection
tower, and pumped into containment on the deck of the vessel. Because of the unique EST design, the amount
of water collected is minimized. Once the container is full, the boat is
taken to shore and off-loaded mechanically or using the vessel’s pumps. The algae can then be taken to
an appropriate site for composting. Aerobic composting will avoid the production of methane (a potent
greenhouse gas). Assuming the dried, mature compost from the algae is used to enhance soil for growing
crops, the net greenhouse gas emissions from the algae harvesting, production and application of compost
should be near zero (assuming short transport distances or transportation powered by biofuels or electric
The image above illustrates the electric drive system, control console and open work deck.
For clarity, it does not portray the EST collection tower and related equipment.
Future processing options could include a facility where the algae can be processed to produce liquid
fuels and other by-products of value. (RESTCo has a long-standing relationship with
Algepower, a leader
in wastewater reclamation and biofuel production based on algae cultivation.) Addition of an
motor fueled by biodiesel can speed transiting operations to and from the
work area (paddle wheels lift to reduce vessel drag in the water).
The EST technology can be fitted to other boat forms, including conventional monohull workboats,
barges, pontoon boats and catamarans. This flexibility in form factors means the EST vessels can
be used for other activities when not required for algae collection (e.g., oil spill response, collecting
micro-beads, nurdles and other small floating pollution items from bodies of water, fire-fighting, cargo
transport, personnel transport, environmental monitoring, dive support, marine recovery, harbour or
coastal patrol, etc.) Thus, the algae skimmer vessel can be easily and quickly deployed to other
activities when not required for algae harvesting.
Once the initial algae bloom has been harvested, RESTCo recommends the relevant water quality authorities
WCI to improve and maintain the oxygen levels in the water, improving the overall water quality.
RESTCo - working toward self-reliant, resilient communities and a better environment for all.