Megan Ray Nichols is a STEM writer and blogger. More of her work can be found on SchooledByScience.com, and she can be reached at [email protected].
From at-home purification devices to industrial-scale wastewater treatment plants, water is all around us at one stage of treatment or another. As technology seeps into our lives more and more, it's not a surprise to find it in the water treatment industry as well, improving performance, efficiency and convenience. Here's a look at what's happening in water treatment today.
Drinking Water Treatment and Desalination
If there's an invention that exemplifies out-of-the-box thinking in water treatment, it's the Warka Water Tower.
The creators of the water tower won awards for the ingenuity of their design, which consists of a massive bamboo cylinder wrapped in a synthetic mesh made from post-consumer materials. The result is a structure which pulls in water from rain, fog, dew and humidity, filters it and channels it into collection basins. It even provides a shaded gathering spot. The structure is cheap enough and quick enough to assemble that we could expect to see them just about everywhere starting at the end of 2019, which is when the Warka Water Tower should begin mass production.
Then, there's a technology with implications for home use, industrial-scale water treatment and developing parts of the world where potable water can be hard to come by. It's graphene filters. According to researchers, we're two years away from graphene-based household water treatment units and five years away from industrial-scale versions. So what are they?
In short, they're a complement to reverse osmosis, which cleans and desalinates water using a semi-permeable membrane. Reverse osmosis is the gold standard for water treatment units designed for cleaning polluted water and making saltwater sources drinkable, which could be lifesaving in a disaster.
Graphene filters are just one atom thick, affordable and long-lasting. They substantially improve the flow of water through a treatment system, and they reduce the energy cost of desalination by 20%. You may have these filters in your home, treating your water, sooner than you think.
Cities and Municipalities Turning to Technology
Treating city and municipal water supplies and making them ready for consumption and reuse is an activity that's even grander than industrial-scale. With tax revenues and budgets a consistent political football, it makes sense for local governments and utilities to look for technologies which can reduce the expense and labor involved in operating water treatment plants. Automation is an ally here, with more than a few technology companies offering digital and automated management platforms.
These solutions involve using sensors to take readings of water composition, changes in water pressure and temperature and signs of equipment being compromised, like reduced flow signifying a leak in the plant somewhere. Automated plant management systems can instruct aerators, pumps and other equipment to kick on as needed, depending on real-time conditions, to adjust pH, temperature or alkalinity, or bring impending equipment maintenance issues to the attention of management.
The introduction of biogas systems has been another win for the industry. The city of Gresham, Ore., has achieved the ultimate dream for wastewater treatment plants: It produces and sends back more electricity to the city's grid than it consumes in its operations. The facility manages this by harnessing solar power and by producing biogas onsite and then putting it right to work. After the upgrade, Gresham taxpayers enjoyed a savings of half a million dollars per year.
Plenty of other cities are finding novel ways to put technology to work, too. In Boise, Idaho, and Madison, Wisc., sewage treatment plants use a series of mechanical and chemical steps to recover phosphorus from wastewater before the clean water returns for use by the public. In doing so, they support the manufacture of environmentally friendly fertilizers, in which phosphorus is a crucial ingredient.
There's always been a lot going on behind the scenes when it comes to our drinking water, but now there are even more reasons to learn about the process and how new techniques and technologies are continually changing it.
Industrial Wastewater Treatment
According to a UNESCO report called "Wastewater: An Untapped Resource," the world's volume of industrial wastewater will double by 2025. UNESCO identifies manufacturing as the most significant contributor of wastewater among all industrial activities.
Oil and natural gas production is another, which is why automation is getting a lot of notice among companies engaged in hydraulic fracking. This industry produces a significant amount of wastewater, and often on sites that are inconvenient to reach. Thankfully, technology has advanced to the point where companies can purchase or lease portable, automated, industry-ready water treatment systems. Some of these turnkey systems use induced-gas flotation in addition to filtration to reduce oils, greases and suspended solids to just 10 parts per million, making it ready for reuse onsite or someplace else. No more trucking dirty water away.
Another proposed solution, this one out of Boulder, Colo., would instead use microbes to clean the wastewater produced by hydraulic fracking and other industrial activities. The technique is called "microbial capacitive desalination," and it works by using microbes to generate a current, which then desalinates wastewater. But this invention goes one step further: Incredibly, the process generates more energy than it consumes, which means there's potential here to capture that energy and use it in other processes onsite.
We're in an opportune moment for such technologies, as oil and gas companies produce some 18 billion gallons of wastewater every year between them.
Water Is an Age-Old Challenge
Many roads have brought us to this point. The distribution of water is a tale as old as time, and one we're still in the process of adequately solving. It's clear that with the right technologies, territories with plentiful water can learn to meet their needs without a higher-than-necessary ecological price tag. Meanwhile, purification and desalination technology is becoming more and more accessible and affordable to those in developing parts of the world.
Wastewater treatment benefits from technological progress in other fields. Graphene, for instance, has implications in various areas, including energy storage. With the right social and civic pressure, and wise investments from the private sector, all the people of the world will soon enjoy clean water and reliable water infrastructure, thanks to affordable and efficient technologies.
