(90g) An Economical and UV Assisted Crumb Rubber Device for Harnessing Drinking Water from River

Drinking water shortage is becoming a very challenging problem for future due to the impact of calamities such as climate change, storms, burst of population and sinking water tables. In the last decade new techniques such as nano filtration, reverse osmosis, and solar distillation have been developed. Many developing countries find the new techniques expensive. In the work conducted at COMSATS Lahore, use has been made of recycled crumb rubber which is originally a source of breeding of mosquitoes. Crumb rubber fortunately acts as a very good filtration media because of its elasticity and porosity. In the experimental work, sizes of crumb rubber ranging from 1.2 – 4.2mm and 5.0 – 6.5mm were used to create columns for filtration. The average porosity was 0.50. The pilot plant consisted of a rectangular glass chamber 1.0m height and 0.62m width with a gravel support 0.3m. Glass tubes were inserted in the column to count the head loss. A UV reactor with immobilized nano-TiO₂ was attached for intake of the effluent after filtration. River water with turbidity of 238(NTU) and coliform count of 238(MPN/100ml) was used as effluent. After filtration it was found that the crumb rubber size 1.2 – 4.2mm was found to be highly effective in reducing the turbidity from 238(NTU) to 4.2(NTU) with 90% efficiency. The head loss was found to be minimum at a depth of 0.3m compared to other media depths. The turbidity decreased with increasing filtration rate of 12m³/hm³. On final treatment by the photocatalytic reactor no presence of coliform was observed. The drinking water quality was in accordance with WHO specifications. The above technique has been found to be cost effective and it can be scaled up for large scale applications.