DRAWING from an age-old craft of pottery and adding to it cutting edge nanotechnology has created the candle-type ceramic water filter that now serves some communities without potable water.
The launching and ceremonial turnover of the water-filter technology to the University of Northern Philippines was a highlight of the Science Nation Tour for the Northern Luzon Cluster, a project of the Department of Science and Technology (DOST), which was held recently in Vigan, Ilocos Sur. The theme for the Science Nation Tour is “Agham na Ramdam: Science for Every Mang Juan [and Aling Maria].”
Science Secretary Mario G. Montejo said at the Science Nation Tour that addressing the problem of lack of potable water, especially in the countryside and remote areas, is one of the priorities of the DOST.
“This project is a blend of old artisan work and science, which is enhancing the old practice with nanotechnology,” he said.
The idea of using clay filters is an old one, but the process we used is our own, Montejo said. Every type of clay has its own properties and will need different processes, he explained.
The lack of potable water has, in fact, become a global crisis. The World Health Organization and the United Nations Children’s Fund have identified a population of 750 million in the world with no access to clean water and 82 percent of these live in rural areas.
In the Philippines 20 percent have no access to potable water with 432 municipalities without water-service facilities. Healthwise, some 31 percent of illnesses in the country are caused by water-borne diseases.
Forty-five percent of water sources in the country are supplied by community-based associations, which unfortunately are largely untreated water which can carry bacteria that cause the spread of water-borne diseases.
Microfiltration, like ceramic-based micro filters, is a proven technique to eliminate microbial contaminants. Based on this the Industrial Technology and Development Institute of the DOST provided the unique ceramic filtration system using very local material.
This ceramic water filter uses red clay abundant in many areas. Clay samples from different parts of the country—such as Ilocos Sur, Isabela, Tarlac, Isabela, Aurora, Camarines Sur, Sorsogon, Aklan, Leyte, Cagayan de Oro, South Cotobato, Pampanga and Mountain Province—were analyzed and showed they were suitable for processing into water filters with nanotechnology.
“We cannot just keep adding coatings to the clay. This has to be prepared in a way that will accept the nano material,” Montejo said. Silver, known for centuries to be an antibacterial mineral, is added to the clay filter. Silver is a nano material, Montejo added. Production entails the clay to be meshed to a measured fineness and mixed with water and other combustible material. Water impurities are sifted. Silver ions are trapped between the spaces in the slightly porous clay.
When water flows through the filter, the silver ions kill the pathogens in the water, including coliform bacteria and protozoa.
There are now four production centers of this ceramic water filter: Eliano Baluyot Pottery Inc. in Arayat, Pampanga; University of Northern Philippines in Vigan, Ilocos Sur; the local government of Santa Maria, Isabela, in Cagayan Valley; and Bila Pottery Association in Bila, Mountain Province.
The DOST tapped on existing pottery establishments and had them trained on the formulation technique of the water filters with nanotechnology. The formulation has been carefully tested and standard tests yielded heterotrophic plate count to be less than 30, where the standard should be less than 500 colonies per plate count. It also passed safety tests for coliform and E. coli.
The initial design was of a cumbersome clay pot but Montejo suggested a lighter more portable design made of white translucent plastic composed of a pitcher that holds the raw material and another catchment that holds the clay filter, and when assembled resembles the shape of the candle, thus, its name. The product weighs 500 grams only and has a maximum filtering flow rate of 2 liters per hour.
The DOST has rolled out these water filters to beneficiaries in Vigan City, Catanduanes, Iloilo, Zamboanga and Autonomous Region in Muslim Mindanao. A thousand units were given to Supertyphoon Yolanda victims. An order of some 50,000 units were made from disaster-prone areas.
“We are hoping that there will be adopters to help roll out the product to areas with no potable water,” Montejo said.
The production cost is at P300 and the plastic assembly is P112. The unit can be bought for about P450.
Next commercial sites being developed are the CAR, Bicol, Eastern Visayas and Cagayan de Oro in Mindanao.
The candle-type ceramic water filter is also considered a climate-change adaptation technology, an ideal solution for disaster stricken areas where access to roads to deliver bottled water becomes a problem. Thus, every household or family in evacuation centers can have clean drinking water with just this invention made available to them, DOST-CAR Regional Director Julius Caesar Sicat said.
The ceramic water filter can purify tap water, deep well water and water from ponds and springs.
Image credits: Gerry Palad, STII S&T Media Service