Hey Folks,
This week we discuss the varied powers of dogs, polyester, iron, gallium and not to be trifled with….data! If you like what you read, do comment, share and of course, subscribe.
Disclaimer - the views expressed herein are ours and ours alone.
Canine Leak Detection Services
Got water leaking out of your system and you can’t find it? No problem for the sniffer dogs! This British company has trained their dogs to sniff out hints of chlorine from water leaking from hidden mains supply pipes, and thereby saving water. The company’s founders were dog trainers in the British army, training dogs to find explosives etc. On leaving the army, the founders started a business using sniffer dogs to find bedbugs and other vermin.
They heard that someone in Australia was training dogs to sniff out water leaks and decided that would be pretty good business to expand into. They then trained their springer spaniels to sniff out the smell of chlorine and identify leaks that way. They have already found leaks that (when plugged) will save over a 110,000 liters/day. Kudos!
Biosand (bacteria) filters for Lake Erie
Seeing the limitations of existing treatment methods, such as the removal of micropollutants and hazardous waste, a team of researchers at University of Toledo, Ohio developed biofilters with sand filters containing active bacteria. The bacteria were ones found naturally occurring in Lake Erie that have enzymes, capable of breaking down microcystin (a toxin released by algae). For those who have not had the opportunity to read older editions of this newsletter, we did a piece on how dangerous algae is to the health of water bodies and the associated flora/fauna.
This Biosand filter contains bacteria that is cheap to produce, safer than conventional chemical treatments and can even be used in non-liquid contamination situations e.g. landfills and waste disposal systems. The filters have proven to remove algal toxin levels significantly greater than the World Health Organization guidelines.
Aluminium oxide nano-sheets trumps heavy metal ions
A team of Australian researchers have discovered a cheap way to manufacture filters that can remove heavy metal contaminants from drinking water in a matter of minutes. They go on to say that low cost and portable filters produced by this new ‘liquid metal’ based manufacturing process could be used by people without access to clean drinking water to remove substances like lead and other toxic metals. Also, it is really economical - the researchers say that there are portable filtration products available that remove heavy metals from water, but they often cost more than $100. By their ‘liquid metal’ method, the filters could be produced for as little as 10 cents!
What is this liquid-metal process? - a chunk of aluminium is added to the core of liquid gallium at room temperature. In the ensuing chemical reaction, flakes of aluminium oxide are quickly produced at the surface of the gallium. Each 0.03mm flake is made up of about 20,000 nano-sheets stacked together. These nano-sheets are highly porous, and heavy metals like lead have a very high affinity to aluminium oxide. As the water passes through billions of layers, lead ions get attracted to one of these aluminium oxide sheets. As they bond, the affinity is so strong that even with repeated use, the water flow cannot detach the heavy metal ions from the aluminium oxide.
Chlorine resistant Polyester membranes
Drawing inspiration from swimsuits that are inherently chlorine resistant, a research team at Yale have created a chlorine resistant membrane out of polyester. Why? - Chlorination is a common practice to prevent fouling (gunk stuck to the filters) in municipal water supplies, wastewater reuse and seawater desalination. However, composite reverse osmosis membranes—the premier technology for desalination and clean-water production—structurally deteriorate when continually exposed to chlorine.
Rather than reinvent the entire membrane, this team decided on a multi-layered approach. First, they took the existing gold standard - polyamide nanofiltration membrane (which can get messed up by chlorine), then they added a layer of polyester on top of the membrane at a nanoscopic level. What this did was create a multilayer membrane resistant to chlorine, which performed as well as the conventional membrane in terms of water permeability and desalination performance.
Iron particles to break-up PFAS
Researchers at Southern Illinois University (SIU) have developed a process that uses photocatalysis to remove PFAS from water. SIU’s project is focused on finding an elegant, low-cost way to remove the toxic PFAS substances from wastewater effluent so that it can safely be reused for agricultural purposes. Photocatalysis as the name suggests is a process by which light is used to accelerate a chemical reaction. SIU’s team is using iron nanoparticles in photoreactors to remove PFAS from water samples.
The system when completed will include a sequencing batch photoreactor, using zero-valent iron nanoparticles and an ultraviolet C-radiation light, along with a magnetic chamber used to separate the used iron particles. The system will treat water both in the SIU lab and at Northwest Wastewater Treatment Plant in Carbondale, Illinois.
In other news, researchers from Cornell University and North Carolina State University have now developed a Hydrology Data Tool that draws from multiple databases to give water resource managers and infrastructure users the information they need to make informed decisions about water use on river networks. This information they say will help with managing water systems efficiently, for ensuring that infrastructure can continue operating successfully, particularly during extreme conditions, such as flooding or drought.
To demonstrate the tool's utility, the researchers used the algorithm to create a connectivity network demonstrating the interconnectedness of about 1,400 reservoirs and 1,600 streamgages in the upper and lower Colorado River basins.
That’s all folks! Stay warm, hydrated and keep that mask on! Also if you like what you read, share it with your friends!
Peace