B'luru student designs filter to purify Bellandur water

Ever imagined that fruit peels could turn out to be a boon to scale down the froth in Bengaluru's filthy lakes?

This city college student proves its feasibility with his low-cost biotic semipermeable membrane made out of fruit peels. Interestingly, Pavan A, a second-semester student at the MVJ College of Engineering, has already conducted an experiment using intensely polluted water of Bellandur Lake and obtained positive results.

Working on the project, Pavan created an activated semipermeable biotic membrane made of acidified watermelon, banana, pineapple and citrus peels that help remove the frothing agents from the lake water. He tested the water sample from Bellandur Lake at the Central Environmental Laboratory, Karnataka State Pollution Control Board, Shivajinagar, and inferred positive results.

"I tested the water sample for the presence of fluorides, one of the main substances in water that causes froth and other substances like nitrates and phosphates. The water sample from Bellandur Lake contained 3.3 mg per litre of fluorides in it. After purification using a biotic semipermeable membrane, it came down to 0.27 mg per litre," said Pavan.

Explaining how fruit peels purify water, he says: "These peels are placed one above the other in the filter separated at a small distance between each other such that the water flows through the peels without getting stagnant. Contaminated water or the effluent is passed through the filter from a higher gradient which removes all the solutes."

It occurred to him unexpectedly when he was going through some of the international scientific journals to seek information for one of his college projects on the internet. "I came across an article in a Nigerian journal about the use of fruit peels to purify water. That was the time when the froth in Bellandur Lake had triggered a debate. I thought I should implement this idea to purify the lake water. Fortunately, I got good results," he said.

Talking about the implementation of his project at large scale, he adds: "It is not feasible to use biotic semipermeable membrane for the actual industrial application as it is not feasible to pile up the required amount of fruit peels. We need larger equipment that will be expensive. I will continue my research and find an alternative to it. However, the biotic semi-permeable membrane can be used to purify a small amount of water and it is cost-effective."