Greetings All,

De-colonizing WASH interventions might suggest that people are doing these for themselves, not dependent on external resources. Producing and implementing candle water filters can be remarkably simple almost anywhere, depending primarily on existing human and natural resources. What is primarily needed is capacity building.

The production of monolithic ceramic water filters, e.g., candle filters, is incredibly simple, and needs to be standardized. A clay composition consisting of powders of clay and charcoal can be formed by potters into the candles, then dried and fired, giving a porous ceramic for good flow rates. End caps for the candles can be fired clay or plastic. Once these candle filters are giving consistent flow rates they should be treated with aqueous silver. Key to success is good record keeping throughout the development and production.

The candles need to be fired for a second time, at the low temperature of 550C, in order to burn off what is not silver, that other constituent of the silver compound or the dispersant, in order to burn this off and bond the silver metal to the ceramic. With attention to proper procedure the resulting candle filters will reduce pathogens to the highest standard, e.g., log 6 reduction (99.9999% effectiveness) and should last for at least ten years. There is a serious need to standardize the production of candle filters.

Any project producing candle filters might do well to fabricate insulating rocket stoves at the same time. There are numerous synergies between candle water filters and the curved bricks of these stoves, both in production and implementation. The community that undertakes these together will gain resilience and self-sufficiency.

Once kilns are fabricated to fire at higher temperatures, communities will be able to fabricate sanitary ceramic toilets. The reason that I am aware of these possibilities goes back to a time that I lived in Liberia, eleven years throughout my twenties, working for the churches. My neighbors, the women and children, were constantly coughing due to cooking on open fires. The children were getting sick and dying, largely because their mothers were told in radio advertising to give them powdered milk. Then they mixed this with contaminated water.

Such observations motivated me to return to school, resulting in my enrollment at the New York State College of Ceramics at Alfred University. I became a ceramic industrial designer, focused on developing these kinds of interventions. The ceramic engineering professors subsequently verified, for example, that silver bonds to a ceramic, given that second firing. They verified that the insulating ceramic liners of stoves could easily be made using a clay composition of the type described. These days, however, those producing stoves are unaware of clay compositions, erroneously thinking that an insulating ceramic can consist of a single constituent material.

It is frustrating that those promoting safe drinking water and clean cookstoves do not talk to academic ceramists and experts. If they did, they would have a better understanding of the materials, what works and what does not. Rather, those promoting water filters and clean cookstoves go through a lot of puzzlement and unnecessary research and assessment. It is frustrating that there is so little understanding of just what ceramics is.

Ceramic science is the study of inorganic, non-metallic substances at high temperatures. The ceramic scientist tells us that the earth's crust is composed entirely of ceramic raw materials. Potters are all over the developing world, producing for their communities, essential products such as water containers and cook pots. Once they are trained in some of the simple production steps of clean cookstoves and water filters, they will be knowledgeable in processes that are at the origin of industry. Further capacity building could industrialize their communities and countries.

Is it too much to dream that the developing world could be a part of the industrial world? I think not but convincing others is frustrating. And by the way, while there are such simple means of production, the children continue getting sick and dying. I can only suppose that I must blame myself. Experts are aware that the interventions described here work but I have not done well at convincing others.

Reid

Anthony Reid Harvey, ceramic industrial designer

Niagara Falls, NY USA