At least 780 million people in the world lack access to clean water, a dire problem exacerbated by the increasing number of people living in poorly-equipped refugee camps. Researchers from KTH Royal Institute of Technology in Sweden may have come up with a low-cost, low-tech solution: a portable wood filter that doesn’t require a power source to produce clean water.
KTH scientists developed a material from wood cellulose that can trap bacteria, and are testing the material for use as a water filter. PhD student Anna Ottenhall said, “Our aim is that we can provide the filter for a portable system that doesn’t need electricity – just gravity – to run raw water through it…The bacteria-trapping material does not leach any toxic chemicals into the water, as many other on-site purification methods do.”
The wood cellulose fibers utilized are antibacterial, and are dipped in a positively-charged polymer solution to create the material, which works since bacteria and viruses are negatively charged, according to Phys.org. The harmful viruses and bacteria stick to the material, unable to get free or reproduce, and eventually die. Another benefit of this method of purification is that bacteria won’t be able to build up a resistance to it.
The Swedish research team envisions their material used as a water filter in places that lack wells or infrastructure, like refugee camps or in emergencies. After use, the material can simply be burned. Bandages, packaging, and plasters could potentially draw on the material as well to dispose of bacteria in ways that don’t put toxins into the environment.
KTH researchers are developing several other wood-based materials along with this wood water filter, such as see-through wood, a wood polystyrene alternative, and squishy wood batteries.