Pitt | Swanson Engineering
History of Low-Cost Ceramic Water Filters

Ceramics have been used to store household water for thousands of years. However, the use of porous ceramics to filter bacteria and particulates from drinking water is much more recent.  There are several types of very effective ceramic materials on the market for filtering potable water.(1)(2)  Additionally, porous ceramics are now also used in bioreactors for wastewater treatment.  Unfortunately, these filters are commonly too expensive to address the problem of delivering, safe potable water to people in developing countries. 

In 1981 Dr. Fernando Mazariegos of the Central American Industrial Research Institute addressed this problem by designing a porous clay filter impregnated with antibacterial silver nanoparticles.(3) A crucially important aspect of this technology is that it could be made by local potters in Guatemala and offered the potential for a sustainable technology.

Potters for Peace (PFP) was founded in 1986 and began work with Mika Seeger in Nicaragua in 1988.(4)  PFP hired Ron Rivera to coordinate their exchange activities in Nicaragua in 1989.  At this time PFP was not heavily involved in the production of the low-cost water filters, although Rivera did work with the Mazariegos water filter in Ecuador.

In 1994, the Family Foundation of the Americas did a health study to determine the effect of Dr. Mazariegos’s hand thrown water filter in Guatemala. The results showed that the filters resulted in a 50% reduction in the incidence of diarrhea in households involved with the project.(3)

In 1998, PFP became much more involved in the development of the low-cost water filter in response to the devastation caused by Hurricane Mitch in Central America.(3)(4)  They organized the Filtron workshop in Nicaragua which made 5,000 filters that were distributed through local NGO’s.  This activity has resulted in a privately owned filter production facility near Managua and also inspired successful training programs that have set up filter production facilities in many countries around the world.  PFP and its volunteers have also been heavily involved in technical developments concerning the filters, the clay formulations, filter presses and kilns.  An example of the latter is the “Mani Kiln” designed by Professor Manny Hernandez of Northern Illinois University which has reduced the amount of fuel needed for a wood fired kiln by 50%. (5) The full range of PFP activities continues today.

Other Organizations such as Potters without Borders(6), Resource Development International - Cambodia(7) and FilterPure(8) have also used the PFP model to established filter production facilities in countries such as Yemen, the Dominican Republic, and Cambodia.  Additionally, the concept has also been widened to establish purpose driven education programs based on the ceramic water filter in the US. Among the first of these is the TAMU water project,(9) founded by Professors Stephen Carpenter and Oscar Munoz of Texas A&M University.  This project aims to use the filter to provide an educational experience and supply water filters to families in the Texas Colonias communities.

The Pittsburgh Region

In Pittsburgh we are fortunate to have several organizations involved in different aspects of the low-cost ceramic water filter ranging from material design to implementation and field testing.  First among these involves the efforts of Professor Dick Wukich of Slippery Rock University.  Dick was amongst the potters that went to Nicaragua with PFP after Hurricane Mitch.  Since that time he has been involved in filter project in several countries including Iraq and Honduras.  Dick is now involved with Pure Water for All, (10) a local Pittsburgh NGO that continues to undertake projects related to the ceramic water filter.  In 2006 Pure Water for All partnered with the Pittsburgh Chapter of Shoulder to Shoulder (11) and Professor Manny Hernandez to develop a filter production facility in Northern Honduras which supplied filters to the community of San Jose at a cost of $19 each.  A further study in 2008 showed that the filters did improve water quality but education and proper maintenance procedures will be essential for further improvements.

Dick Wukich has also been instrumental in establishing the ceramic filter processing facility at the Braddock Ceramic Studio (BCS) in the community of Braddock, Pittsburgh.(12)  Currently, the filter production at BCS is coordinated by Jeff Schwarz a professional potter and full-time AmeriCorps volunteer.  BCS provides filters to customers including the University of Virginia, where research is ongoing on filter effectiveness.

Work began on the University of Pittsburgh Ceramic Filter Project in the fall of 2007.  Curtis Larimer, a student in Engineering Physics, had visited Campinas, Brazil the previous summer on an IRES project organized by the Mascaro Center for Sustainable Innovation at the University of Pittsburgh.  The project collected information concerning drinking water in Brazil and concluded that the household water box was an important source of contamination.  Upon returning to Pittsburgh, Curtis approached Dr. Ian Nettleship to supervise a senior design project concerning the water box contamination.  The project examined the low-cost water ceramic filter and in particular the impregnation method used to apply the silver nanoparticles.  The work showed severe segregation of the silver nanoparticles to the external surfaces of the filter.  In the summer of 2008 another IRES project returned to Brazil under the supervision of Dr. Nettleship. The IRES team collaborated with Professor Ricardo De Lima Isaac of UNICAMP University in Campinas (13) to examine the suitability of ceramic water filters for household water boxes.  The results suggested that the permeability should be increased by an order of magnitude.  Curtis Larimer is now an IGERT fellow in the Mascaro Center for Sustainable Innovation at the University of Pittsburgh.  Curtis is working towards a PhD supervised by Dr Nettleship.  Their work, in part, will involve a further collaboration with Professor Isaac at UNICAMP to change the clay formulation to increase the permeability while still removing bacteria from the water.  In 2009 Dr Willie Harper joined the Ceramic Water Filter Project with specific interests in the effect of the ceramic filter on water quality and the use of low-cost ceramic filter in bioreactors for waste water treatment. Dr. Judy Yang has also recently joined the project to help characterize the nanoparticles and their surfaces by transmission electron microscopy.

     We would like acknowledge that we have not been involved with filter activities for long enough to have a comprehensive knowledge of the history of the subject.  Much of the early history of the water filter and PFP’s efforts was written using the Potters for Peace website as the primary source.  If the reader is aware of further information on water filter activities that are not mentioned above (especially with sources other than website URLs) please contact Dr Nettleship at the address below.  Furthermore if the above account misrepresents important developments please contact us.  Thanks. 

- Ian Nettleship
nettles@pitt.edu

 

Last Updated April 13, 2009

 

References
1. http://doultonusa.com/
2. http://www.stefaniterracotta.com/index.php
3. http://s189535770.onlinehome.us/pottersforpeace/?page_id=9
4. http://s189535770.onlinehome.us/pottersforpeace/?page_id=2
5. http://s189535770.onlinehome.us/pottersforpeace/wp-content/uploads/general-info-hand-out.pdf
6. http://www.potterswithoutborders.com/
7. http://www.rdic.org/waterceramicfiltration.htm
8. http://www.filterpurefilters.org/
9. http://tamuwaterproject.wordpress.com/
10. http://www.purewaterforall.org/index.htm
11. http://www.shouldertoshoulderpgh.org/
12. http://www.angelfire.com/planet/braddockarts/home.html
13. http://www.fec.unicamp.br/itf/index_1.php?pg=97.php&dpto=7&secaoGeral=19