Water Up-Cycling and Microgrids

04 OCT 2018
Upcycling usually refers to the creative re-use of normally waster materials such as plastics and metals. However upcycling can also refer to the treatment of water from waste to usability without losing the water from the water supply system.

Typical waste water treatment discharges the water into the natural environment typically rivers or seas. However in regions where the sources of water are limited this is truly wasteful. A better way is to close the loop and treat waste and gray water so that it can be used again without discharge. In some cities water is cycled almost infinitely with the only loss being through evaporation. For instance in those countries reliant upon desalination it is cheaper to treat gray water to fresh, that it is to desalinate fresh seawater.

But such systems are large, expensive and impact upon the environment through the huge use of carbon fuels to drive the desalination and treatment systems. There has to be a better way.

Microgrids are typically applied to small scale electrical systems not connected to a main national electrical grid. With solar a common source of power, solar powered microgrids can aid remote and isolated communities to reduce the use of costly and carbon intensive diesel gensets.

But just as municipal water systems act like a grid so too can small water upcycling plants. Such facilities are small, serve remote communities and allow them to avoid costly reticulation of fresh and waste water. How might such an Upcycling Water Microgrid work?

First gray water is treated to remove hard solids, and emulsified. Then a period of settling allows the waste liquid to go through a porcess of nano-treatment by a series of oxygenated biofilms. This metabolizes the waste, produces no explosive methane, and leaves behind clear treated water. This is then exposed to UV radiation to kill off any lingering bacteria or viruses before being sent back into the system as flushing and irrigation water. There is some solid sludge produced, but this can be heat treated and deposed of in a landfill, or used as feedstock for a bio-digester for the production of methane.

Such a system can be driven by solar during the day, with night time operation typically unnecessary. Or the methane could drive a gas cycle generator or fuel cell.

The benefits of such a system are that expensive and limited supplies of fresh water can be used for high quality uses - for drinking and hand washing. This leaves the flushing and irrigation water to use the treated gray water. It would still be possible to further process this water to Reverse Osmosis and thus bring it to full potable water level, but in any event there would always be a need for make up water. This could be in the form of rain water or from other fresh water sources.

Where might such a system be used? In any desert setting where water is scarce such a system or on site treatment would dramatically reduce the use of fresh water... and more importantly sewage would be reduced. But not only desert communities could benefit, remote toilet facilities for communities or National Parks. Or for larger residential developments where the cost of reticulating sewage is prohibitive or time consuming.

Water Upcycling Micrigrids are a system that we believe have many benefits and are working to bring to markets in Asia, Australia / New Zealand, and North America. If you are interested please contact us.
By Adaptiv Earth