Researchers have developed a new combination of old water filtration methods. By mixing plant proteins and sand particles they’ve created a system that is better then either one alone.
The use of sand to filter water goes all the way back to ancient Egypt. For example, the Egyptians used porous clay pots filled with sand in a process known as slow sand filtration.
During this procedure contaminated water sifts through sand and heavier particulates of impurity are “caught on” the silicate (sand) particles. Generally speaking the deeper the sand bed the more effective (and slower) the degree of purification. The end result – cleaner water for drinking and thereby less chance of catching contagious disease.
During ordinary sand filtration a layer of bio-film also coagulates at the top of the sand which further aids in filtration by offering an extra layer of protozoa and algae that can digest bacteria in the water.
Moringa seeds have also been used as a rudimentary form of sand filtraton in India and other tropical/subtropical climates. By grinding them in to a powder and pouring them in to a container filled with contaminated water the negative charged silt clay bacteria and toxins bind with the positively charged water soluble organic proteins of Moringa and sink to the bottom allowing for easy filtration by removing the bottom layer.
As for combining the two Professor Velegol from Penn State University came up with the idea while PHD student Brittany Nordmark from Carnegie University developed the process.
It involves adhering a layer of Moringa proteins to the top of these sand beds. Moringa proteins act in a similar way to the algae and protozoa in ordinary sand filtration. However, Instead of solely dealing with micro-organisms the Moringa proteins also bind to Clay, Silt, and other inorganic toxins as – expanding the range of this upper layer to include more particulates and improving the overall process.
These researchers have demonstrated that the method displays a high degree of flexibility, working in both hard and soft water conditions allowing for application to a large range of geographic regions. This of course make it a promising method for water filtration in developing nations around the world.