Elaboration of Ceramic Pot Filter from Kaolinite (Cameroon Clay) for the Elimination of Suspended Particles from Domestic Drinking Water

The objective of this work was to elaborate ceramic water filters from Kaolinite (Cameroon) clay for the elimination of suspended particles from domestic drinking water. In Sub-Sahara Africa and in Cameroon in particular health issues have been linked to the consummation of domestic tap water of high turbidity values both in the rural and urban areas. In order to remedy these problems, ceramic water pot filters have been elaborated in a pilot scale unit with aim of putting in place a unit production. The chemical composition, the thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) analyses of the raw materials (clay and rice husks) was determined. The crystal phases and scanning electron microscope of Wack clay was also determined. The ceramic pot filter membranes were fabricated from the formulations 70/20/10 of clay/porogen/chamotte respectively with the particle size of the raw material less than or equal to 500 μm. The formulated ceramic pot filters were then sintered at 900˚C in a furnace. These ceramic pot filters were characterized by determining their porosity, withdrawal percentages, water permeability, mechanical and chemical resistance. The study of the efficiency consisted in evaluating the retention rate and permeate flux with respect to time (days) with synthetic water suspensions of turbidity 100 NTU and particle size of 2 μm. The ceramic pot filters were made aiming at studying the efficiency after physical defouling of filters. Physical defouling consisted in brushing the inner surface of the ceramic pot filters with water and drying them at ambient temperature after being used for 11 days and reusing them under the same initial conditions. The produced ceramic pot filter had a volume of 4 L, an average porosity of 36.15%, shrinkage in mass or withdrawal percentage of 18.23%, a water permeability of 59.6 × 103 L∙h−2∙m−2, mechanical resistance of 6.8 MPa and corrosion resistance of 1.6% in acidic medium and 0.8% in alkaline medium. The evaluation of the retention efficiency reveals that the retention rate of 99.9% was obtained from the 9th day of filtration reducing the turbidity value from 100 NTU to less than 0.1 NTU. From the filtration test carried out during the 11 consecutive days, the flow rate varied between 1.46 L∙h−1 to 2.63 L∙h−1. Similar results of retention and flow rate were obtained after physical defouling of the ceramic pot filter membranes and re-using for 11 consecutive days, showing the efficiency of the ceramic pot filter membranes in eliminating suspended particles from drinking water. Cost evaluation for the production unit reveals a total cost of production for 50 ceramic pot filters of 1593.6 USD consisting of fixed assets and variable assets. An estimated selling price of 3.3 USD was obtained which is affordable for both the urban and rural population in Cameroon and in sub-Saharan Africa.

Elaboration of Ceramic Pot Filter from Kaolinite (Cameroon Clay) for the Elimination of Suspended Particles from Domestic Drinking Water

The objective of this work was to elaborate ceramic water filters from Kaolinite (Cameroon) clay for the elimination of suspended particles from domestic drinking water. In Sub-Sahara Africa and in Cameroon in particular health issues have been linked to the consummation of domestic tap water of high turbidity values both in the rural and urban areas. In order to remedy these problems, ceramic water pot filters have been elaborated in a pilot scale unit with aim of putting in place a unit production. The chemical composition, the thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) analyses of the raw materials (clay and rice husks) was determined. The crystal phases and scanning electron microscope of Wack clay was also determined. The ceramic pot filter membranes were fabricated from the formulations 70/20/10 of clay/porogen/chamotte respectively with the particle size of the raw material less than or equal to 500 μm. The formulated ceramic pot filters were then sintered at 900˚C in a furnace. These ceramic pot filters were characterized by determining their porosity, withdrawal percentages, water permeability, mechanical and chemical resistance. The study of the efficiency consisted in evaluating the retention rate and permeate flux with respect to time (days) with synthetic water suspensions of turbidity 100 NTU and particle size of 2 μm. The ceramic pot filters were made aiming at studying the efficiency after physical defouling of filters. Physical defouling consisted in brushing the inner surface of the ceramic pot filters with water and drying them at ambient temperature after being used for 11 days and reusing them under the same initial conditions. The produced ceramic pot filter had a volume of 4 L, an average porosity of 36.15%, shrinkage in mass or withdrawal percentage of 18.23%, a water permeability of 59.6 × 103 L∙h−2∙m−2, mechanical resistance of 6.8 MPa and corrosion resistance of 1.6% in acidic medium and 0.8% in alkaline medium. The evaluation of the retention efficiency reveals that the retention rate of 99.9% was obtained from the 9th day of filtration reducing the turbidity value from 100 NTU to less than 0.1 NTU. From the filtration test carried out during the 11 consecutive days, the flow rate varied between 1.46 L∙h−1 to 2.63 L∙h−1. Similar results of retention and flow rate were obtained after physical defouling of the ceramic pot filter membranes and re-using for 11 consecutive days, showing the efficiency of the ceramic pot filter membranes in eliminating suspended particles from drinking water. Cost evaluation for the production unit reveals a total cost of production for 50 ceramic pot filters of 1593.6 USD consisting of fixed assets and variable assets. An estimated selling price of 3.3 USD was obtained which is affordable for both the urban and rural population in Cameroon and in sub-Saharan Africa.

Physico-Chemical Characterization and Stability Study in Acidic and Basic Solution of Ceramic Filters from Mouka’s Clay (Cameroon)

This paper deals with the characterisation and study of physico-chemical stability of ceramic filters from clays and rice husk obtained from the far north region of Cameroon (Logone Valley) and their application in potable water treatment. Clays from Mouka were characterized by FTIR analysis. The results showed that the filter formulated with a mixture containing 80% clay and 20% rice husk of 100 μm in size each gave the lowest filter shrinkage rate;these formulated filters were chosen for the remaining work. Leaching tests showed that with filters at a sintering temperature of 830°C the leaching was not observed under neutral (pH 6.8) and acidic (pH 5) conditions as compared to 950°C and 1000°C where the leaching was observed. In basic (pH 9) condition, all the filters obtained released ions. Leaching tests revealed that the conductivity of the leachate for the filters sintered at 830°C was lower than those sintered at 950°C and 1000°C. Meanwhile, conductivity decreases with increasing sintering temperature (temperature up to 830°C) due to the fact that ceramization starts as from 850°C that leads to an amorphous state that favours chemical stability, the leaching ions were Fe2+, Ca2+, Mg2+ and Al3+. The ceramic filters sintered at 950°C were applied to the filtration of water and the performance in terms of turbidity reduction was 95% and the flow rate after 50 minutes was 100 × 10−3 L/h.

Identification of an Appropriate Formulation for Domestic Water Ceramic Filters from Soukamna Clay(Cameroon)

This paper deals with the formulation of ceramic filters having the porosity adapted to domestic potable water treatment.The filters were made from clays and rice husk obtained from the Far North region of Cameroon(Logone Valley).Nine formulations were investigated to choose those that might have the porosity standing between 35 and 50%(the ideal porosity adapted for water treatment).The nine formulations investigated were as follows:clay:rice husk mixture weight ratio 0.7:0.3;0.8:0.2 and 0.9:0.1 with the particle size of 100:100 microns.The sintering temperatures of 900℃,950℃ and 1000℃ were applied for each of the mixtures.The results showed that only filters with weight ratio 0.7:0.3 sintered at 900℃,950℃ and 1000℃ had porosity between 35 and 50% with values of 39.41±0.96;40.15±1.59;40.14±1.31 respectively.Mechanical strength,permeability and iron leaching behavior were investigated for these three formulations.The formulation 0.7:0.3 with sintering temperature of 1000℃ had the higher permeability and was the more stable for iron leaching so it is the more adapted for water treatment in terms of flow rate and iron leaching behavior,pore size distribution showed that these filters were macroporous and designed for microfiltration with average pore diameter of 0.46μm.