Next Generation Wastewater Treatment Uses Hydrodynamic Forces to Clean Water
Water is precious on this planet. Clean water is even more precious.
And we can't just magically produce more water at a given place and time when we need it, so most of what we can do is become more efficient and conservative in our use and reuse of it, especially on the industrial and municipal scales.
One of the strategies for water conservation and recovery at those levels is improving the process of separating the biomass from the clean water in wastewater plants, and a new filterless technology from PARC might be another big step in that direction.
The Hydrodynamic Separation (HDS) technology developed by PARC is uses a combination of centrifugal force and hydrodynamic forces to efficiently remove suspended particles and concentrate biomass without using any type of filter. The system is said to be capable of high rates of flow, use low energy (or use a gravity-fed source), and because of its compact size and modular design, can be scaled up or down to fit the site.
Here's the scoop, for you fluid dynamics fans:
"Centrifugal force creates transverse flow patterns in a curved channel, which under certain circumstances manifest themselves as a pair of Dean vortices. As particles flow down the channel, they spiral around the Dean vortex cores while a combination of drag and shear-induced forces move them toward the channel center. Under the correct conditions (specified by channel geometry and flow rate), this dynamic causes the particles to focus into a band near the outside wall. At the end of the length of the channel, the single flow is separated into two flows: the concentrate and effluent outputs.
Although HDS technology leverages centrifugal force, it is different than centrifuges and hydrocyclones. Instead of relying on density differences between particles and fluid, HDS technology is solely based on hydrodynamic forces, resulting in a particle size dependent separation that allows for direct concentration of particles of any density, including neutrally buoyant ones." - PARC
The HDS system could be used in both conventional and membrane wastewater plants, for treatment of water from gas and oil extraction facilities or other industrial processes, to pre-treat seawater for desalination, to separate oil from water, or to recover other precious resources from wastewater streams.