Hey Folks,
This week we have a bunch of innovations to clean water and some telling news in the world of water, so let’s get into it.
Disclaimer - the views expressed herein are ours and ours alone.
Sunflower pollen to clean up oil spills/ clean water
A team of scientists from the Nanyang Technological University, Singapore (NTU Singapore) and Sungkyunkwan University in South Korea, have created a reusable, biodegradable sponge from sunflower pollen. This sponge has the unique property of repelling water (i.e. it is hydrophobic), which given the topics covered in this newsletter - sounds counterintuitive. However, what is magical here is that its water repellent qualities can soak up oil and other organic solvents from contaminated water sources, making it a promising alternative for tackling marine oil spills.
What makes this creation all the more awesome is that it is from a biodegradable product (see sunflower pollen above) whereas the current options available for oil spills are either not capable of actually removing the oils from water OR are such complex chemical products that once they absorb the oil, they are not biodegradable (making them a problem for the next generation). Before you ask what that looks like, remember the situation in Florida from a week ago? They have shared some more specifics for how they converted pollen into an absorbent gel, and you can read about it here.
Darkling beetle > radiative cooling >> clean water
Let’s open with a Nat-Geo style format: the darkling beetle native to the Namib Desert in Africa is unique in that, when it comes to the desert surface at night it sheds body heat to the atmosphere. This shedding of heat results in the beetle cooling to below dew point (i.e. the temperature below which dew forms on the cooler surface, like a car windscreen on a hot day). This beetle is then able to harvest that water, using special grooves and structures to direct the moisture toward its mouth. Oh, the wonders of nature!
Learning from the beetle, engineers at the University of Buffalo and the University of Wisconsin-Madison, have built a water vapor condenser that works off direct sunlight with no other power source. They constructed their device using a thin film of material called polydimethylsiloxane (PDMS) that is very efficient at releasing thermal radiation i.e. condensing water in direct sunlight. They then layered that over silver, which reflects sunlight. The combination of the two cools the condenser below the dew point, leading to condensation. All hail the Beetle!?
Nanofiltration to replace RO+UV
An innovative Dutch company has built what they call hollow fiber nanofiltration membranes. They are in the process of piloting this technology to clean water in a province in Holland. Why does this new tech catch our eyes? - Well we have talked in the past about the limitations of reverse osmosis (RO) based membrane filtration and how most commercial water purification setups have to use RO in conjunction with ultraviolet (UV) or ultrafiltration to get clean potable water at the other end.
This new technology - hollow fiber nanofiltration membranes will eliminate the need for the second step i.e. UV/ultrafiltration. Given that having a power source is a big concern with most of the developing world, should this pilot pan out, it will make energy consumption on this method of water cleaning that much lesser, not to mention avoid the use of pre-treatment and remineralization chemicals in the cleaning process.
Desalination waste brine recycled as plant food
An agrobiotechnologist (we still can’t say it either) and his team at the Spanish National Research Council, have been leading a project to reduce the amount of brine dumped into the ocean by recycling it as plant food. This team mixed waste brine with extra essential minerals needed for plant growth to form a fertilizer similar to a widely used supplement for hydroponic plants. They then used this mixture to grow tomatoes.
With refreshing honesty they admitted that the yield was less than with regular hydroponic growing methods, but that because the tomatoes inherently like salt, the brine-grown tomatoes had a sweeter taste and a deeper red color. Next up they will try the same technique with watermelons. Next stop gazpacho!
PFAS disposal with no toxic by-products - use Hot water!
For regular readers of this blog you will know all about PFAS and the associated pain-in-the-water-body. This tech startup born out of a bunch of good research, is aiming to resolve the PFAS contamination in the US by using hot compressed water. While a lot of the information is shielded for patent reasons, as best as we can tell, they have developed a portable bolt-on system that works with whatever water pumping system is being used by the client.
This bolt-on unit, uses high pressure to compress the water and thereby break the carbon-fluorine bonds in PFAS. Once this most strong bond breaks, all the other chemical bonds break up, forming non-toxic chemicals in the water. They then pump this to a filtration unit that separates the non-toxic chemicals and voila! clean water. Yes we know it is light on information but we still wanted to share with you!
In Other News
This week we have more telling news from around the world about the deteriorating state of our clean water supply.
We wrote a few months ago about the Japanese government planning to dump fukushima radioactive water into the Pacific Ocean. We even detailed some Swiss scientists looking to help clean the water before it was dumped. Well that day is here. Despite protests from all its neighboring countries on the matter, Japan will release more than 1 million tonnes of contaminated water from the destroyed Fukushima nuclear plant into the sea. They say they will filter the water so that only tritium, a radioactive isotope of hydrogen hard to separate from water is left in the water, and that too below the permissible safe levels but this all sounds dicey at best.
In other news, as reported by the NY Times, drought in Taiwan is pitting their in-demand microchip makers against farmers. Drought was always a contentious point and the long held belief was, the farmers that feed us come first. With a big chunk of Taiwan’s GDP/ fight for continued independance coming from their ability to be a global player, they have gone the other direction and supported the chip makers instead who need the water to make the chips that the world is running on now. With this new point-of-view being taken, which developing nation will be the next to de-prioritise agriculture? India?
Strontium in the water - Yeah, the US needed this like another hole in the head, but a new study by the United States Geological Survey found that almost every groundwater sample across 32 U.S. aquifers had detectable strontium levels, while 2.3 percent exceeded 4 milligrams per liter (mg/L), the maximum amount that people should consume routinely.
Also in the ‘You-Cannot-Make-This-Stuff-Up’ category - A group of 36 former and current Atlanta prison inmates filed a lawsuit against the city because officials allegedly gave them water tainted with toxins such as arsenic. While not directly claiming poisoning, they are saying the water supplied to the prisons was not devoid of toxins. The water is provided by the city’s Department of Watershed Management. The city office says that initial tests show there is nothing wrong with their water, but doesn’t this all sound like a story we have heard somewhere? Flint, Michigan perhaps?
To wrap up we wanted to leave you with one piece of good news: Singapore, the city-state has been water-limited for a long time. They have turned to desalination to help tide them over, but as always they are going the extra mile by using treated water from four sources - rainfall from local catchments, imported water, desalination, and recycled water, which is known locally as NEWater. While desalination is their biggest push as the one pseudo-limitless source of water for the island nation, it is really good to see them using recycled water and rainwater harvesting as well.
Well that is it for this week folks, as always write to us with your thoughts and feedback. And remember to hydrate and stay safe! Until next Friday,
Peace!