One of the things I think is really cool that we’re testing on board the International Space Station is the water reclamation system. ~Peggy Whitson, Astronaut
You’re probably not thinking about how refreshing a tall glass of cool water is during the winter. That thought came to my mind when reading about Trump stripping pollution safeguards from drinking water sources — one of Obama’s efforts to help save our environment.
Of course, in addition to food and air, clean drinking water is required for life on this planet, and there is a shrinking supply. Reverse-osmosis desalination of seawater has been around for decades, but is very energy-intensive and may have an adverse environmental impact on marine life.
In this issue, you’ll learn about some cool water technology: how salt can be filtered out of seawater with low energy costs, how water can be extracted from thin air, and even recycled indefinitely.
Scientists Develop ‘Nanopores’ That Inexpensively Filter The Salt Out of Seawater
Most seawater is made drinkable through reverse osmosis, but it is expensive:
Conventional desalination relies on reverse osmosis to channel seawater through a thin plastic membrane, but the process suffers from a number of bottlenecks. While the membrane appears thin to the eye, from a microscopic perspective it’s more tube- or tunnel-like than a sheet that’s only a nanometre in thickness, which means it requires more pressure (and thus energy) to operate. They’re also susceptible to more clogging, which ramps up operational costs.
Researchers have been looking for a new way to filter water, including graphene nanopore filters, but there is even a better filter on the horizon. There is also another approach using ionic liquid separation.
Good News: The new filter material is a nanometer-thick sheet of molybdenum disulfide (MoS2) riddled with nanopore holes — filtering up to 70 percent more water than graphene. The other approach, ionic liquid separation, uses geothermal or industrial heat instead of electricity. These new energy-efficient desalination methods promise to help solve the water crisis!
Water-from-air, at Home or in the Office
Who hasn’t experienced condensation dripping from an old window air conditioner or from your car on a hot day? I’m sure you wouldn’t want to drink that water, but what if a device was available to extract clean drinkable water from thin air at a much lower energy cost?
Here are two approaches: Watergen uses a patented plug-in generator that provides purified water and dehumidifies the air. The other device, Source Hydropanel from Zero Mass Water, extracts water from air using solar panels.
Good News: These solutions require no public utility infrastructure and can extract water from even dry air. Both can operate at the household level (plug in a Genny like a water cooler or put the Source Hydropanel on your roof) or at an industrial scale.
Recycle Your Residential Water
In countries where water consumption is restricted or expensive, lack of access to usable water affects hygiene and comfort, to say the least. Why flush our used water down the drain when we can recycle it?
Maybe you can’t drink recycled water, but you can clean and disinfect shower, bath and washing machine gray water to be reused for toilet flushing, gardening, pool water or to be recycled back to the washing machine. This Consumer Electronics Show Innovation Winner can do just that.
Good News: The new Hydraloop patented recycling technology requires no filters, membranes or chemicals, and is fully automatic, and self-cleaning. It helps households “reduce water consumption and water bills by 45 percent, sewage emissions by 45 percent and carbon footprint by 6 percent.”
The next time you drink that cool glass of water, think about how lucky most of us are to be able to just turn on a tap. Fortunately, scientists are working to help those less fortunate here (e.g., Flint, Michigan) and around the world to be able to sustain life using this cool new water tech.
Dr. Rod Murray