Removing algae from municipal waste water

Restoring the health of natural waterways

Aquaflow has been harvesting wild algae from the municipal waste water ponds in Blenheim, New Zealand, for over two years. This pilot operation has continued throughout all seasons, including temperatures below freezing, processing 70m3 of algae laden water per hour.

This process utilises Aquaflow’s unique algae harvesting and dewatering technologies. Algae laden waste water is pumped through the Harvester which separates the algae from the water. This water can then be further upgraded for use in agriculture, industry or to be safely returned to the environment. Algae harvesting utilises mechanical processes and other agents to concentrate the algae from the very low densities present in the waste water. This makes a slurry of algae which can then be further concentrated in our dewatering process, producing a heavy paste.

The removal of algae from waste water has the added benefit of removing the nitrates, phosphates and other pollutants that algae feed on. Algae photosynthesise, absorbing carbon dioxide from the atmosphere and releasing oxygen. The algae that are removed from the waste water can be used as biomass in a number of other processes including conversion into Green Crude™ and its derivatives. Municipal ponds provide the perfect environment for algae cultivation: a large surface area open to sunlight and extensive supplies of the essential nutrients of nitrogen and phosphorous. Aquaflow is using established open-air ponds to harvest algae for conversion to biofuels.

Our harvesting technology is well advanced and we are looking for sites to install larger pilot programmes that establish the scalability of this process. Our second generation Harvester will provide further improvements in algae removal, water quality and energy efficiency.


Multi-Green Fuels™ demonstration
facility »

Blenheim Municipal Wastewater »
Pilot clean up programme at Lake Rotorua »
Sequestering industrial waste demonstration project »
Green Crude™ Refining
Partnership »



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