Our clay is harvested locally from sites owned by Pure Home Water just outside of Tamale. The clay is dried in the sun, then pounded into a powder and sifted to remove any gravel or organic matter like roots. Before pressing the pots, we mix fine rice husk into the clay. This combustible material will burn out when the pot is fired, leaving pores behind that the water can pass through. After mixing in the rice husk, water is added until the clay is wet enough to shape on the press, but dry enough so that it will hold its shape. After pressing, the filters are moved to racks where they will air-dry for a period of days or weeks, depending on the season. When they are almost completely dry, they are loaded into one of our kilns and fired according to best practices established by the Ceramics Manufacturing Working Group, a group of experts who surveyed similar filter factories all around the world to establish filter manufacturing standards. After firing, when the filters have cooled, each filter undergoes quality assurance tests to make sure that there are no cracks in the filter and that its flow rate is within the acceptable range. Multiple filters from each batch are also tested to ensure adequate bacteria removal. Currently, our filters remove 90% of bacteria before even being treated with colloidal silver, which is the final step in production that happens to all filters that pass the QA testing. Colloidal silver is a disinfectant that increases the bacteria removal of our filters. Once treated, the AfriClay Filter can remove up to 99.9% of bacteria!
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