scholarly journals Removal of hardness from drinking water by electrocoagulation using iron electrodes

2021 ◽  
Vol 9 (11) ◽  
pp. 1413-1417
Keyword(s):  
Drinking Water ◽  
Reaction Time ◽  
Water Distribution ◽  
Electrical Potential ◽  
Water Hardness ◽  
Maximum Efficiency ◽  
Total Hardness ◽  
Batch Mode ◽  
Hardness Removal ◽  
Study Laboratory

In the present study laboratory studies are carried out to examine the removal of hardness by electrocoagulation process from drinking water using iron rod electrodes in batch mode. The purpose of this study was to investigate the efficiency of EC process in removal of water hardness through iron-rod electrodes in varying conditions. Experimental water sample was taken from water distribution network of local area Pune City, Maharashtra state, India. The indices for calcium and total hardness removal in pH (4.0, 7.0, and 10.0), electrical potential of 12 and 24 V and reaction times of 5 minutes to 30 minutes were measured. The maximum efficiency of hardness removal which was obtained at pH 10.0, voltage of 12 and reaction time of 60 min are equal to 98.5% and 97.5% for calcium and total hardness, respectively. Final pH of remained solution has also increased which rises with acidic pH and decreases in alcoholic pH, so the results demonstrate the direct effect of pH, potential difference and reaction time on hardness removal using EC process.

scholarly journals EXPERIMENTAL HYGIENIC ESTIMATION OF CALCIUM AND MAGNESIUM CONCENTRATIONS IN DRINKING WATER, AND ITS HARDNESS

2019 ◽  
Vol 98 (8) ◽  
pp. 811-819
Author(s):  
E. M. Trofimovich ◽  
S. A. Nedovesova ◽  
Roman I. Aizman
Keyword(s):  
Drinking Water ◽  
Thyroid Hormones ◽  
Quantitative Estimation ◽  
Experimental Studies ◽  
Water Hardness ◽  
Blood Parameters ◽  
Plasma Metabolites ◽  
Total Hardness ◽  
Calcium And Magnesium ◽  
Plasma Magnesium

Introduction. The lack of hygienic norms for Mg2+ and Ca2+ in drinking water and the wide ranges of acceptable hygienic norms (AHN) of these cations in water packaged in containers determine the relevance of experimental studies on the substantiation of AHN of Mg2+, Ca2+ and the hardness of drinking water with a centralized water supply to the population. Material and methods. Chronic experiments were performed on 5 groups of adult Wistar rats (n = 50): control animals received drinking water (Ca2+ 20.0; Mg2+ 6.0 mg / dm3, hardness 1.5-1.8 mEq/dm3); four other groups received model drinking water with different contents of Ca2+ (50, 80, 100 and 140 mg/dm3) and Mg2+ (20, 40, 55 and 85 mg/dm3) by adding CaCl2 or MgSO4 salts to the control water. The effect of these drinking water samples on kidney function, ion osmotic blood parameters, plasma metabolites of lipid and protein metabolism, as well as the concentration of thyroid hormones (T3 and T4) and cortisol were studied. Results. Prolonged action of increased concentrations of Ca2+ and Mg2+ on the organism was established to cause alterations in fat metabolism, the adaptive activation of osmoregulatory and ion regulatory kidney functions, increasing the concentration of thyroid hormones and a decrease of cortisol titer in plasma. Magnesium led to more pronounced changes in water-salt metabolism, and at a concentration of 85.0 mg/dm3 (7.0 mg-Eq/dm3) - to depletion of secretion of the described hormones. Conclusion. Based on the obtained results, individual ranges for AHN of calcium and magnesium concentrations in water were recommended. The upper limit of AHN of drinking water total hardness is of 7.0 mg-Eq/dm3 at the joint presence of Ca2+and Mg2+. The rule of hygienic qualitative and quantitative estimation of calcium and magnesium types of drinking water hardness is formulated.

scholarly journals QUALITY OF DRINKING WATER IN MINING AREAS

2019 ◽  
pp. 104-109 ◽  
Author(s):  
R. F Khasanova ◽  
Ya. T Suyundukov ◽  
I. N Semenova ◽  
Yu. S Rafikova
Keyword(s):  
Water Quality ◽  
Drinking Water ◽  
Water Supply ◽  
Iron Content ◽  
Water Distribution ◽  
Manganese Content ◽  
Distribution Networks ◽  
Water Distribution Networks ◽  
Total Hardness ◽  
Mining Areas

The paper presents the results of a drinking water quality study in towns located in the mining areas of the Republic of Bashkortostan, The Russian Federation. The objects of the study were underground water supply sources and water distribution networks of the towns of Uchaly, Sibay, and Baimak. In total, 30 water wells were examined, and five water samples were collected from the water distribution network in each town. The water quality indicators were pH, solid residue, total hardness, copper content, zinc content, iron content, and manganese content. The water quality in water distribution networks corresponded to the permissible limits according to environmental and sanitary regulations, except for the increased iron contentprobably due to corrosion of water supply pipelines. The water quality in non-centralized water supply (wells) in some areas failed to meet the sanitary standards. Priority indicators of water pollution were increased hardness and mineralization, high content of iron and manganese. To provide the residents with high-quality drinking water, it is proposed to make a complete inspection of centralized and non-centralized water sources not only within the towns, but also in the neighbouring communities. It is necessary to install filtration plants, primarily to reduce the iron content, in roder to bring the water taken from the wells for household and drinking purposes to the standard quality.

The Influence of Total Hardness on Chlorine Decay in Water Distribution Systems

2014 ◽  
Vol 535 ◽  
pp. 776-784
Author(s):  
Jing Qing Liu ◽  
Wei Jiang ◽  
Jian Min Wu ◽  
Cong Li
Keyword(s):  
Drinking Water ◽  
Metal Ions ◽  
Distribution Systems ◽  
Water Hardness ◽  
Free Chlorine ◽  
Chlorine Concentration ◽  
Total Hardness ◽  
Decay Constants ◽  
Chlorine Decay ◽  
The Impact

Free chlorine decay is a main issue in drinking water treatment since free chlorine concentration is a common indicator in drinking water security. The current view of free chlorine decay is that the process is mainly affected by the natural organic matter in water, temperature and initial chlorine concentration, on which temperature has the most evidently effect. As is generally accepted, total hardness has no effect on it. This paper investigated the impact of water hardness on the chlorine decay. The influence of varying metal ions concentrations which contribute to water hardness on effective chlorine decay constants was assessed. The results implied that total hardness had an evidently influences on the chlorine decay in tap water or DI water. For the range of metal ions concentration in this experiment effective chlorine decay constants ranged from an increase by +182% to +349% from the different concentration of metal ions.

The assessment of biofilm community composition on plumbing materials in filtered and unfiltered water distribution systems

2003 ◽  
Vol 3 (1-2) ◽  
pp. 187-191
Author(s):  
M.M. Critchley ◽  
N.J. Cromar ◽  
H.J. Fallowfield
Keyword(s):  
Drinking Water ◽  
Fatty Acid ◽  
Community Composition ◽  
Distribution Systems ◽  
Water Distribution ◽  
Water Distribution Systems ◽  
Polymer Materials ◽  
Fatty Acid Profiles ◽  
Water Supplies ◽  
Drinking Water Distribution Systems

Biofilms have been extensively characterised within drinking water distribution systems. However, the significance of materials on biofilm species diversity is not established. This study investigated the community composition of biofilms on plumbing materials receiving filtered and unfiltered water supplies. Biofilms were extracted from polybutylene, polyethylene, cross-linked polyethylene, unplasticised polyvinyl chloride and copper tubes in sampling rigs receiving Murray-Onkaparinga water before or after filtration. Biofilms were extracted and analysed for fatty acid composition using the FAME™ methodology. There were differences in the fatty acid profiles of biofilms and the respective water supplies, indicating differences in the attached and planktonic communities. The results also showed significant differences in the fatty acid profiles of biofilms on the polymer materials compared to copper, suggesting variations in biofilm populations on the different materials. The potential for materials to select for microbial populations has significant implications for the ecology of drinking water biofilms.

Assessment of Lisbon drinking water distribution network biofilm colonization and associated hazards

2008 ◽  
Vol 8 (4) ◽  
pp. 421-426
Author(s):  
J. Menaia ◽  
M. Benoliel ◽  
A. Lopes ◽  
C. Neto ◽  
E. Ferreira ◽  
...  
Keyword(s):  
Drinking Water ◽  
Distribution System ◽  
Water Distribution ◽  
Water Distribution System ◽  
Water Distribution Network ◽  
Storage Tanks ◽  
Water Pipe ◽  
Cultural Methods ◽  
Drinking Water Distribution ◽  
And Storage

Concerns arise from the possible occurrence of pathogens in drinking water pipe biofilms and storage tank sediments. In these studies, biofilm samples from pipes and sediments from storage tanks of the Lisbon drinking water distribution system were analyzed. Protein determinations and heterotrophic counts on pipe biofilm samples were used to assess the Lisbon network sessile colonization intensity and distribution. Indicator and pathogenic microorganisms were analyzed in pipe biofilm samples, as well as in storage tanks biofilm and sediments, by using cultural methods and PCR, to assess risks. Results have shown that the Lisbon network sessile colonization is relatively weak in intensity. In addition, no meaningful hazards were apparent for both the network biofilm and the storage tanks biofilm and sediments.

Nitrite and Nitrate Levels in Groundwater, Water Distribution Network, Bottled Water and Juices in Iran : A systematic Review

2020 ◽  
Vol 21 ◽  
Author(s):  
Maasoumeh Marhamati ◽  
Asma Afshari ◽  
Behzad Kiani ◽  
Behrooz Jannat ◽  
Mohammad Hashemi
Keyword(s):  
Drinking Water ◽  
Water Distribution ◽  
Scientific Information ◽  
Distribution Network ◽  
Water Distribution Network ◽  
The Body ◽  
International Standards ◽  
Nitrogen Fertilizers ◽  
Nitrate Content ◽  
Nitrate And Nitrite

Background: Nitrate and nitrite can get into the body through the consumption of contaminated water either directly or indirectly. The accumulation of these compounds in the body, in the long run, leads to health problems, for example, digestive disorders, cancers, and even death threats in children. The aim of this review is to investigate nitrate and nitrite pollution levels in drinking water and fruit juices in Iran. Methods: In this review data were collected through searching the Scientific Information Database, Science-Direct, Scopus, PubMed, Google Scholar, and Magiran databases using the keywords Nitrate, Nitrite, Drinking water, Drinking Water Resources, Juice and Iran. Finally, the location of the studies was geocoded through the Google My Maps (https://www.google.com/mymaps) software. Results: Studies clearly indicated that the juices are safe in terms of nitrate. Nitrate and nitrite values were less than the national and international standards in all samples of bottled drinking water except for a few of the studies. The results of the reviewed studies also indicated that the nitrate content was higher than that written on the label in 96% of the samples, and nitrite was not labeled in 80% of them. The nitrate quantity was higher than the permissible limit, in the water distribution network of Bushehr, Gilan and Mazandaran Provinces. Talesh, Ardabil, Hashtgerd, Divandareh, and Kerman cities had high nitrate levels in more than 50% of wells. Conclusion: Using nitrogen fertilizers and lack of a wastewater treatment system were the main reasons for the presence of nitrate and nitrite.

scholarly journals Identification of Aminoglycoside Resistance Genes From Bacteria Isolated From Selected Municipal Drinking Water Distribution Systems in Southwestern Nigeria

2020 ◽  
Vol 41 (S1) ◽  
pp. s255-s255
Author(s):  
Ayodele T. Adesoji ◽  
Adeniyi A. Ogunjobi
Keyword(s):  
Drinking Water ◽  
Distribution Systems ◽  
Water Distribution ◽  
Water Distribution Systems ◽  
Multidrug Resistant ◽  
Resistant Bacteria ◽  
Multidrug Resistant Bacteria ◽  
Southwestern Nigeria ◽  
Drinking Water Distribution Systems ◽  
Drinking Water Distribution

Background: Multidrug-resistant bacteria can lead to treatment failure, resulting in infectious diseases being transferred through nonpotable water. Aminoglycosides are an important class of antibiotics that are abused in Nigeria. Few studies have investigated aminoglycoside-modifying genes (AMGs) that are likely responsible for resistance in Nigeria bacteria isolates. Therefore, we aimed to characterize AMGs from isolates in drinking water distribution systems (DWDS) in southwestern Nigeria. Methods: Multidrug-resistant bacteria (n = 181) that had been previously characterized by 16S rDNA sequencing and that were positive for resistance to at least 1 aminoglycoside antibiotic were selected from 6 treated and untreated water distribution systems. Strains were PCR genotyped for 3 AMGs: aph(3)c, ant(3)b and aph(6)-1dd. Results: Of 181 MDR bacteria tested, 69 (38.12%) were positive for at least 1 of the AMGs. The most common was ant(3)c (27.6%), followed by aph(3")c (18.23%). Both aph(3)c and ant(3")b were found in 7.73% of tested isolates, ant(3)b was most commonly found in Alcaligenes spp (50%). Furthermore, aph(3")c was most commonly detected in Proteus spp (50%). Other genera positive for AMGs included Acinetobacter, Aeromonas, Bordetella, Brevundimonas, Chromobacterium, Klebsiella, Leucobacter, Morganella, Pantoae, Proteus, Providencia, Psychrobacter, and Serratia. Conclusions: High occurrence of ant(3)c and aph(3)c among these bacteria call for urgent attention among public health workers because these genes can be easily disseminated to consumers if present on mobile genetic elements like plasmids, integrons, and transposons.Funding: NoneDisclosures: None

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