scholarly journals Alternative Electrode Materials and Ceramic Filter Minimize Disinfection Byproducts in Point-of-Use Electrochemical Water Treatment

2013 ◽  
Vol 30 (12) ◽  
pp. 742-749 ◽  
Author(s):  
Yeojoon Yoon ◽  
Youmi Jung ◽  
Minhwan Kwon ◽  
Eunha Cho ◽  
Joon-Wun Kang
Keyword(s):  
Water Treatment ◽  
Electrode Materials ◽  
Disinfection Byproducts ◽  
Ceramic Filter ◽  
Point Of Use

Antibacterial silver-diatomite nanocomposite ceramic with low silver release

2019 ◽  
Vol 20 (2) ◽  
pp. 633-643
Author(s):  
Xiaopeng Qi ◽  
Junwei Chen ◽  
Qian Li ◽  
Hui Yang ◽  
Honghui Jiang ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Water Treatment ◽  
Photoelectron Spectroscopy ◽  
Bactericidal Effect ◽  
Ceramic Filter ◽  
Ceramic Filters ◽  
X Ray ◽  
E Coli ◽  
Point Of Use ◽  
Silver Release

Abstract There is an urgent need for an effective and long-lasting ceramic filter for point-of-use water treatment. In this study, silver-diatomite nanocomposite ceramic filters were developed by an easy and effective method. The ceramic filters have a three-dimensional interconnected pore structure and porosity of 50.85%. Characterizations of the silver-diatomite nanocomposite ceramic filters were performed using scanning electron microscopy, transmission electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. Silver nanoparticles were confirmed to be formed in situ in the ceramic filter. The highest silver concentration in water was 0.24 μg/L and 2.1 μg/L in short- and long-term experiments, indicating very low silver-release properties of silver-diatomite nanocomposite ceramic filter. The nanocomposite ceramics show strong bactericidal activity. When contact time with Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) of 105 colony forming units (CFU)/mL exceeded 3 h, the bactericidal rates of the four different silver content ceramics against E. coli and S. aureus were all 100%. Strong bactericidal effect against E. coli with initial concentration of 109 CFU/mL were also observed in ceramic newly obtained and ceramic immersed in water for 270 days, demonstrating its high stability. The silver-diatomite nanocomposite ceramic filters could be a promising candidate for point-of-use water treatment.

Morphology, composition and performance of a ceramic filter for household water treatment in Indonesia

2015 ◽  
Vol 10 (2) ◽  
pp. 361-370 ◽  
Author(s):  
K. Matthies ◽  
H. Bitter ◽  
N. Deobald ◽  
M. Heinle ◽  
R. Diedel ◽  
...  
Keyword(s):  
Water Treatment ◽  
Ceramic Filter ◽  
World Health ◽  
Efficient Technology ◽  
Household Water Treatment ◽  
Governmental Organization ◽  
Virus Removal ◽  
Log Reduction ◽  
Point Of Use ◽  
Health Organization

People in rural developing areas often depend on point-of-use water treatment for safe drinking water. A very popular and efficient technology for this is the use of ceramic filters, as promoted by the non-governmental organization Potters for Peace. These filters are already used in many countries worldwide, including Indonesia, where they are manufactured in Bandung, Java by Pelita Indonesia. The filters are made of local clay and combustible material, and coated with silver after firing. However, data available on them are very scarce. The structure, composition, and physico-chemical and microbiological performance of the filter were examined. Pore sizes mostly ranged from 1 to 40 µm and flow rate was about 1.3 L/h. Silver, arsenic and manganese were leaching from the filter in remarkable concentrations. While values for silver were about 0.01–0.02 mg/L, manganese was washed out after a few liters and leaching of arsenic fell below 0.02 mg/L after filtering some liters. With a log reduction of 3–5, efficiency in bacteria reduction was satisfactory in contrast to virus removal which was not sufficient according to the World Health Organization guidelines, with a log reduction below 1.

A new generation low-cost biochar-clay composite ‘biscuit’ ceramic filter for point-of-use water treatment

2020 ◽  
Vol 185 ◽  
pp. 105409 ◽  
Author(s):  
Nhamo Chaukura ◽  
Robert Chiworeso ◽  
Willis Gwenzi ◽  
Machawe M. Motsa ◽  
Wisdom Munzeiwa ◽  
...  
Keyword(s):  
Water Treatment ◽  
Low Cost ◽  
Ceramic Filter ◽  
Point Of Use ◽  
New Generation

scholarly journals Laboratory Efficacy and Disinfection by-Product Formation of a Coagulant/Disinfectant Tablet for Point-of-Use Water Treatment

Water ◽  
2018 ◽  
Vol 10 (11) ◽  
pp. 1567 ◽  
Author(s):  
Félix Légaré-Julien ◽  
Olivier Lemay ◽  
Ulysse Vallée-Godbout ◽  
Christian Bouchard ◽  
Caetano Dorea
Keyword(s):  
Water Treatment ◽  
Treatment Options ◽  
Product Formation ◽  
Disinfection Byproducts ◽  
World Health ◽  
Treatment Technique ◽  
E Coli ◽  
Point Of Use ◽  
Sodium Dichloroisocyanurate ◽  
Health Organization

Coagulant/disinfection products (CDPs) are a point-of-use (POU) water treatment technique that can improve microbial quality, reduce turbidity, and produce a free chlorine residual (FCR), serving as a potentially effective option for decentralized water treatment in a variety of contexts, including humanitarian emergencies. A novel CDP with a sodium dichloroisocyanurate-based disinfectant was evaluated with regard to its laboratory water treatment efficacy and generation of disinfection byproducts (DBPs). The CDP water treatment performance was assessed relative to bacteriological (E. coli) humanitarian water quality objectives, World Health Organization recommendations for evaluating POU water treatment options, and available DBP regulations and guidelines. At least 4 log10 E. coli reductions, for a “highly protective” status with regard to bacterial reductions, were attained in the tested conditions. Treated waters were consistently below 10 MPN/100 mL with regard to E. coli concentrations, with the majority of samples showing no detectable E. coli. For most conditions, target FCR values were not attained. Treated water turbidity levels were mostly between 5 NTU and 10 NTU. DBP levels were below the regulatory and health-based targets for both families of DBPs studied. This study has served to identify the performance envelopes of the CDP tested under challenging conditions.

scholarly journals The Role of Catalytic Ozonation Processes on the Elimination of DBPs and Their Precursors in Drinking Water Treatment

Catalysts ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 521
Author(s):  
Fernando J. Beltrán ◽  
Ana Rey ◽  
Olga Gimeno
Keyword(s):  
Drinking Water ◽  
Water Treatment ◽  
Humic Substances ◽  
Hypochlorous Acid ◽  
Drinking Water Treatment ◽  
Disinfection Byproducts ◽  
Catalytic Ozonation ◽  
Operating Conditions ◽  
Halogen Compounds ◽  
Radiation Sources

Formation of disinfection byproducts (DBPs) in drinking water treatment (DWT) as a result of pathogen removal has always been an issue of special attention in the preparation of safe water. DBPs are formed by the action of oxidant-disinfectant chemicals, mainly chlorine derivatives (chlorine, hypochlorous acid, chloramines, etc.), that react with natural organic matter (NOM), mainly humic substances. DBPs are usually refractory to oxidation, mainly due to the presence of halogen compounds so that advanced oxidation processes (AOPs) are a recommended option to deal with their removal. In this work, the application of catalytic ozonation processes (with and without the simultaneous presence of radiation), moderately recent AOPs, for the removal of humic substances (NOM), also called DBPs precursors, and DBPs themselves is reviewed. First, a short history about the use of disinfectants in DWT, DBPs formation discovery and alternative oxidants used is presented. Then, sections are dedicated to conventional AOPs applied to remove DBPs and their precursors to finalize with the description of principal research achievements found in the literature about application of catalytic ozonation processes. In this sense, aspects such as operating conditions, reactors used, radiation sources applied in their case, kinetics and mechanisms are reviewed.

scholarly journals Methods, Protocols, Guidance and Standards for Performance Evaluation for Point-of-Use Water Treatment Technologies: History, Current Status, Future Needs and Directions

Water ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1094
Author(s):  
Emily S. Bailey ◽  
Nikki Beetsch ◽  
Douglas A. Wait ◽  
Hemali H. Oza ◽  
Nirmala Ronnie ◽  
...  
Keyword(s):  
Drinking Water ◽  
Water Treatment ◽  
Enteric Bacteria ◽  
Current Status ◽  
Household Water Treatment ◽  
Produce Water ◽  
Point Of Use ◽  
Treatment Technologies ◽  
Injury And Repair ◽  
Testing Protocols

It is estimated that 780 million people do not have access to improved drinking water sources and approximately 2 billion people use fecally contaminated drinking water. Effective point-of-use water treatment systems (POU) can provide water with sufficiently reduced concentrations of pathogenic enteric microorganisms to not pose significant health risks to consumers. Household water treatment (HWT) systems utilize various technologies that physically remove and/or inactivate pathogens. A limited number of governmental and other institutional entities have developed testing protocols to evaluate the performance of POU water treatment systems. Such testing protocols are essential to documenting effective performance because inferior and ineffective POU treatment technologies are thought to be in widespread use. This critical review examines specific practices, procedures and specification of widely available POU system evaluation protocols. Testing protocols should provide standardized and detailed instructions yet be sufficiently flexible to deal with different treatment technologies, test microbe priorities and choices, testing facility capabilities and public health needs. Appropriate infectivity or culture assays should be used to quantify test enteric bacteria, viruses and protozoan parasites, or other appropriate surrogates or substitutes for them, although processes based on physical removal can be tested by methods that detect microbes as particles. Recommendations include further research of stock microbe production and handling methods to consistently yield test microbes in a realistic state of aggregation and, in the case of bacteria, appropriately physiologically stressed. Bacterial quantification methods should address the phenomenon of bacterial injury and repair in order to maximally recover those that are culturable and potentially infectious. It is only with harmonized national and international testing protocols and performance targets that independent and unbiased testing can be done to assure consumers that POU treatment technologies are able to produce water of high microbial quality and low health risk.

scholarly journals Evaluation of an environmentally sustainable UV-assisted water treatment system for the removal of Bacillus globigii spores in water

2017 ◽  
Vol 18 (3) ◽  
pp. 968-975
Author(s):  
R. G. Silva ◽  
J. Szabo ◽  
V. Namboodiri ◽  
E. R. Krishnan ◽  
J. Rodriguez ◽  
...  
Keyword(s):  
Water Treatment ◽  
High Efficiency ◽  
Membrane Filter ◽  
Water Security ◽  
Disinfection Byproducts ◽  
Treatment System ◽  
Health Concern ◽  
Environmentally Sustainable ◽  
Inorganic Substances ◽  
The Impact

Abstract Development of greener water treatment technologies is important for the production of safe drinking water and water security applications, such as decontamination. Chlorine assisted disinfection is common and economical, but can generate disinfection byproducts (DBPs) that may be of health concern. DBPs are formed due to the reaction of chlorine with naturally occurring organic and inorganic substances in water. Currently, various innovative technologies are being developed as alternative approaches for preventing DBPs during water treatment. In this study, we evaluated the effectiveness of a novel combination of high efficiency flow filtration and UV disinfection treatment system for the removal of Bacillus globigii (B. globigii) spores in water. The filtration system consists of a charged membrane filter (CMF) that not only helps to remove suspended particles but also reduces the impact of other impurities including bio organisms. In order to get most performance details, the CMF was evaluated at clean, half-life, and end of life (EOL) conditions along with 100% UV transmittance (UVT). In addition, the effectiveness of the UV system was evaluated as a stand alone system at 100% and 70% EOL intensity. The study was conducted at the US EPA's Test and Evaluation (T&E) Facility in Cincinnati, OH, using B. globigii, a surrogate for B. anthracis spores. This non-chemical environmentally-friendly CMF/UV combination system and the stand alone UV unit showed greater than 6.0 log removal of B. globigii during the tests.

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

2017 ◽  
Vol 18 (3) ◽  
pp. 843-852
Author(s):  
Travis D. Gardner ◽  
Joe D. Guggenberger
Keyword(s):  
Water Treatment ◽  
Low Cost ◽  
Total Coliform ◽  
Fecal Coliforms ◽  
Coliform Bacteria ◽  
Limiting Factor ◽  
Water Production ◽  
Pumping System ◽  
Point Of Use ◽  
Logarithmic Reduction

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.

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