Ceramic water filter for point-of-use water treatment in developing countries: Principles, challenges and opportunities

Abstract

Drinking water source contamination poses a great threat to human health in developing countries. Point-of-use (POU) water treatment techniques, which improve drinking water quality at the household level, offer an affordable and convenient way to obtain safe drinking water and thus can reduce the outbreaks of waterborne diseases. Ceramic water filters (CWFs), fabricated from locally sourced materials and manufactured by local labor, are one of the most socially acceptable POU water treatment technologies because of their effectiveness, low-cost and ease of use. This review concisely summarizes the critical factors that influence the performance of CWFs, including (1) CWF manufacturing process (raw material selection, firing process, silver impregnation), and (2) source water quality. Then, an in-depth discussion is presented with emphasis on key research efforts to address two major challenges of conventional CWFs, including (1) simultaneous increase of filter flow rate and bacterial removal efficiency, and (2) removal of various concerning pollutants, such as viruses and metal(loid)s. To promote the application of CWFs, future research directions can focus on: (1) investigation of pore size distribution and pore structure to achieve higher flow rates and effective pathogen removal by elucidating pathogen transport in porous ceramic and adjusting manufacture parameters; and (2) exploration of new surface modification approaches with enhanced interaction between a variety of contaminants and ceramic surfaces.

Suspended solids and bacteria removal mechanisms in ceramic filter and pervious concrete filter: a review

“…The combustible material must be added to clay to produce the pores so that the water can flow through and the contaminant can be trapped in it. The combustible material consists of sawdust, rice husks, agriculture byproducts [7,25], and other organic materials such as coffee and peanut husks [24]. This organic material will burn during the combustion process and will leave pores in the ceramic.…”

“…Meanwhile, point-of-entry is a water treatment system carried out before water enters the household water system [4][5][6]. Some of the technologies used in point-of-use systems are chlorination, coagulation, solar disinfection, ceramic water filter, bio-sand filter [7], membrane filtration, fibre/fabrics filter [3,8,9], and intermittent slow sand filtration [10][11][12][13]. Moreover, a new-promising technology called pervious concrete filter (PCF) can be used to reduce turbidity from the water reaching 95% efficiency [14].…”

“…Ceramic filter (CF) is a point-of-use technology that is widely used in developing countries. CF is made from a combination of clay and combustible materials such as rice husks, sawdust, coffee husks, and peanut husks [7]. The pores in the CF come from combustible organic matter that burns during the combustion process.…”

“…These pores will drain the water and trap the contaminant from the contaminated water. This technology has been proven successful in reducing bacteria reaching >99% or >2 LRV [7,15,16], viruses [17], protozoa [18], organic and inorganic compounds [19]. Unfortunately, high energy is needed reaching 900 ºC -1000 ºC in the ceramic firing process.…”

Analysis of Fouling Characteristics of Diatomite Ceramic Membrane Using Filtration Models

“…The beneficial characteristics of ceramic membranes include fouling resistance, high permeability, good recoverability, chemical stability, and long life. Therefore, ceramic membranes hold great promise for potential applications in water treatment [8]. Diatomite as a material with abundant reserves, low price, abundant pores, huge specific surface area and strong absorbability, scholars are studying the preparation and modification of diatomite ceramic membrane.…”