Ceramic silver-impregnated pot filters for household drinking water treatment in developing countries: material characterization and performance study

2007 ◽  
Vol 7 (5-6) ◽  
pp. 9-17 ◽  
Author(s):  
D. van Halem ◽  
S.G.J. Heijman ◽  
A.I.A. Soppe ◽  
J.C. van Dijk ◽  
G.L. Amy

The ceramic silver-impregnated pot filter (CSF) is a low-cost drinking water treatment system currently produced in many factories worldwide. The objective of this study is to gather performance data to provide a scientific basis for organisations to safely scale-up and implement the CSF technology. Filters from three production locations are included in this study: Cambodia, Ghana and Nicaragua. The microstructure of the filter material was studied using mercury intrusion porosimetry and bubble-point tests. Effective pores were measured with a mean of 40 μm, which is larger than many pathogenic microorganisms. The removal efficiency of these microorganisms was measured by using indicator organisms; total coliforms naturally present in canal water, sulphite reducing Clostridium spores, E.coli K12 and MS2 bacteriophages. The removal of these organisms was monitored during a long-term study of several months in the laboratory. Ceramic silver impregnated pot filters successfully removed total coliforms and sulphite reducing Clostridium spores. High concentrations of Escherichia coli K12 were also removed, with log(10) reduction values consistently higher than 2. MS2 bacteriophages were only partially removed from the water, with significantly better results for filters without an impregnation of colloidal silver. During this study the main deficiency of the filter system proved to be the low water production; after 12 weeks of use all filter discharges were below 0.5 Lh−1, which is insufficient to provide drinking water for a family

2013 ◽  
Vol 68 (8) ◽  
pp. 1757-1762 ◽  
Author(s):  
Krzysztof Piaskowski

Drinking-water treatment sludge (DWTS) is a by-product generated during the production of drinking water where iron hydroxides are the main component of the sludge. The aim of the study presented here was to determine the effectiveness of using ferric sludge from two underground water treatment stations to remove orthophosphates from a model solution. The analyses were performed in static conditions. The sludge was dosed in a dry and suspended form. Using sludge dried at room temperature and preparing the suspension again proved to be much less effective in orthophosphate removal than using a suspension brought directly from the station. An increase in process effectiveness with a decreasing pH was observed for all the analysed sludge. Due to the low cost and high capability, DWTS has the potential to be utilised for cost-effective removal of phosphate from wastewater.


2019 ◽  
Vol 15 (1) ◽  
pp. 48-65 ◽  
Author(s):  
Stephen Siwila ◽  
Isobel C. Brink

Abstract A low-cost multi-barrier drinking water system incorporating geotextile fabric for pre-filtration, silver-coated ceramic granular media (SCCGM) for filtration and disinfection, granular activated carbon (GAC) as an adsorption media and a safe storage compartment for treated water has been developed and tested. The developed system offers a novel concept of point-of-use drinking water treatment in rural and suburban areas of developing countries. The system is primarily aimed at bacterial and aesthetic improvement and has been optimised to produce >99.99% E. coli and fecal coliforms removal. Although particular emphasis was placed on the elimination of bacteria, improvement of the acceptability aspects of water was also given high priority so that users are not motivated to use more appealing but potentially unsafe sources. This paper discusses key system features and contaminant removal performance. A system using SCCGM only was also tested alongside the multi-barrier system. Strengths and weaknesses of the system are also presented. Both the developed and SCCGM-only systems consistently provided >99.99% E. coli and fecal coliforms removal at an optimum flow of 2 L/h. The developed system significantly recorded improvements of aesthetic aspects (turbidity, color, taste and odor). Average turbidity removals were 99.2% and 90.2% by the multi-barrier and SCCGM-only systems respectively.


2021 ◽  
Author(s):  
Gede H Cahyana

Helical or spiral coiled flocculator have not been applied in drinking water treatment yet in Indonesia. There were only a few articles discussed it with different themes like hydrodynamic, floc characteristic, and performance. This study was done to know the efficiency (performance) of helical flocculator with parameters velocity gradient, pipe and helical diameter, flowrate, detention time, coagulant dose. The study was divided into two steps: Jar test to determine the optimum dose of coagulant and flocculation experiments to evaluate the helical flocculator efficiency. Efficiencies were in the range of medium to high. On flowrate 13 ml/second was obtained good results for two pipe sizes but different in helical diameters. In 0.5 inch pipe with 0.8 m helical diameter the turbidity reduction efficiencies were 72.4% and 73.9% and sediment volume were 18.3 ml and 20.0 ml. In 0.625 inch pipe with 0.4 m helical diameter the turbidity reduction efficiencies were 76.7% and 78.5% and sediment volume were 14.3 ml and 19.7 ml. The optimum velocity gradient about 64.9–69.6 persecond and detention time about 438–649 seconds. The results showed that helical flocculator was effective for floc formation. Flowrate, pipe diameter, helical diameter were three key parameters to perform helical flocculator.


Symmetry ◽  
2020 ◽  
Vol 12 (6) ◽  
pp. 933
Author(s):  
Mohamed Boussemghoune ◽  
Mustapha Chikhi ◽  
Fouzia Balaska ◽  
Yasin Ozay ◽  
Nadir Dizge ◽  
...  

This work concerns the preparation of a mineral membrane by the slip casting method based on zirconium oxide (ZrO2) and kaolin. The membrane support is produced from a mixture of clay (kaolin) and calcium carbonate (calcite) powders using heat treatment (sintering). Membrane and support characterization were performed by Scanning Electron Microscopy (SEM), X-ray Fluorescence (XRF), Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), and Raman Spectroscopy. The prepared mineral membrane was tested to treat drinking water obtained from different zones of the El Athmania (Algeria) water station (raw, coagulated, decanted, and bio filtered water). Experimental parameters such as permeate flux, turbidity, and total coliforms were monitored. The results showed that the mineral membrane was mainly composed of SiO2 and Al2O3 and the outer surface, which represented the membrane support, was much more porous than the inner surface where the membrane was deposited. The permeate flux of the raw water decreased with filtration time, due to a rejection of the organic matters contained in the raw water. Moreover, the absence of total coliforms in the filtrate and the increase in concentration in the concentrate indicate that the prepared mineral membrane can be used for drinking water treatment.


2002 ◽  
Vol 2 (1) ◽  
pp. 57-62 ◽  
Author(s):  
W.H. Höll ◽  
K. Hagen

CARIX is an ion exchange process which usually applies a mixed bed consisting of a weakly acidic and a strongly basic exchanger material. Carbon dioxide is applied as the only chemical for regeneration of the exchangers. As a consequence, the effluent contains only the amount of salt eliminated during the service cycle. CARIX allows a combined partial softening/dealkalisation/sulfate/nitrate of drinking water. A modification of the process uses exclusively a weakly acidic cation exchanger and allows a softening/dealkalisation. The process has been realised for drinking water treatment in five full-scale plants in Germany. Results of operation demonstrate that an excellent water quality is provided at fairly low cost.


Author(s):  
Claudia Patricia Vesga-Rodríguez ◽  
Leonardo David Donado-Garzón ◽  
Monroe Weber-Shirk

The Cornell University AguaClara program researches ways to improve the process of potable water treatment at low cost and no energy dependent. A High Rate  Sedimentation (HRS) process that uses upward flow and less area than traditional tanks was investigated. The objective was to analyze parameters affecting HRS tank performance including velocity, density of the floc blanket and location of plate settlers in a laboratory scale HRS tank. Different velocities were set during the experiment, and the resulting performance of the floc blanket was evaluated through continuous turbidity measurements. Results demonstrated that the lab-scale tank allows the creation of a floc blanket and is a versatile design with constraints of visibility and accessibility. In addition, performance of the sedimentation tank improves at lower up flow velocities; however, the study suggests that plate settlers at the top of the tank stabilized the floc blanket at higher velocities, as a consequence of denser floc blankets created by the plates.


Sign in / Sign up

Export Citation Format

Share Document