Use of ceramic pot filter (CPF) technology under pressure in an in-line pumping system

Abstract

Abstract Ceramic pot filters (CPFs) are an effective point of use water treatment device in developing nations due to their low cost and effectiveness. CPFs are gravity fed, typically making water production a major limiting factor to a CPF's lifetime and acceptability. Directly connecting CPFs to in-line pumping systems or systems with an elevated storage tank would allow filter usage for constant water treatment at increased pressures, increasing the quantity of treated water. Ceramic disks were manufactured for testing in a specially designed housing apparatus. Filters of varying thicknesses and clay to sawdust mass ratios were manufactured to fit tightly. Flowrate and microbiological removal efficacy (logarithmic reduction value (LRV)) were determined over the testing period at various pressures. Flowrate values ranged from 2.44 to 9.04 L per hour, significantly higher than traditional CPF technology. LRVs ranged from 1.1 to 2.0, lower than traditional CPF technology but still effective at removing most Escherichia coli and total coliform bacteria. Filters proved effective at removing total and fecal coliforms at pressures less than 70 kilopascals. The optimum filter had a thickness of 3.2 cm and clay to sawdust ratio of 6:1 by mass. Filters proved to be ineffective if flowrates were above 5 L/h.