Preparation and Characterization of Biogenic Chitosan-Hydroxyapatite Composite: Application in Defluoridation

MRS Advances ◽  
2018 ◽  
Vol 3 (36) ◽  
pp. 2089-2098 ◽  
Author(s):  
Agatha W. Wagutu ◽  
Revocatus L. Machunda ◽  
Yusufu Abeid Chande Jande
Keyword(s):  
Drinking Water ◽  
Surface Water ◽  
Fluoride Concentration ◽  
Health Concern ◽  
Coliform Bacteria ◽  
Fluoride Removal ◽  
Biomass Waste ◽  
Batch Mode ◽  
Treated Water ◽  
Hydroxyapatite Composite

ABSTRACTIn Northern Tanzania, high levels of fluoride in community drinking water supply is recognized as one of the major public health concern, the problem is further ameliorated by presence Escherichia coli and fecal coliform bacteria in surface water and shallow wells. Efforts to decontaminate the water involve mostly the use of low efficient bone char for fluoride removal without disinfecting the pathogens. To address this problem, a robust adsorbent which is capable of removing fluoride and microbes simultaneously with minimal diverse impact on the treated water is necessary. Here we highlight development of composite material developed from recycling of crustacean biomass waste from sea food industry. Chitosan polymer, isolated from prawns shell was composited with crab shell derived brushite (CaHPO4.2H2O) to form chitosan-hydroxyapatite composite. XRD and FT-IR analysis confirmed transformation of brushite phases into hydroxyapatite and formation hybrid composite. Fluoride adsorption tests were performed in batch mode to evaluate effectiveness. Defluoridation capacity of up to 6.4 mg/g in field water containing fluoride concentration of 5-70 mg/L was achieved. The best performance was observed with fluoride concentration of 10 mg/L and below. Apart from fluoride removal, the composite also reduced color tint and microbes from surface water samples. The pH of the treated water in most samples remained around 6.5-8.5, which is acceptable for drinking water.

scholarly journals Effects of Calcination Temperature of Naturally Occurring Absorbents on Drinking Water Defluoridation

2020 ◽  
Vol 39 (2) ◽  
pp. 165-176
Author(s):  
Brenda Mndolwa ◽  
Felix Mtalo
Keyword(s):  
Drinking Water ◽  
Calcination Temperature ◽  
Removal Efficiency ◽  
Fluoride Concentration ◽  
Fluoride Removal ◽  
Treated Water ◽  
Calcination Temperatures ◽  
Natural Adsorbents ◽  
Different Temperatures ◽  
Water Quality Deterioration

Currently, in Tanzania, fluoride removal from drinking water is treated mostly using the bone char method. The method has poor acceptability in some religious communities and also causes water quality deterioration in taste and odour if the bones are not properly prepared. The use of local natural adsorbents as an alternative is feasible with limitations of high levels of other impurities in treated water. Locally available gypsum, magnesite and bauxite were converted to adsorbents through calcination. The study was conducted to determine the removal efficiency, best calcination temperature and composite ratio of the three adsorbents for the removal of fluoride from natural drinking water with fluoride concentration as high as 16.7 mg/L. The adsorbent materials were calcined at different temperatures ranging between 3500C and 6000C. Batch experiments were performed and samples were collected at different contact time intervals of 2 minutes to 60 minutes, and residual fluoride was determined. Bauxite had the highest fluoride removal efficiency compared to gypsum and magnesite. The best calcination temperatures were 3500C, 4000C, 6000C for gypsum, bauxite and magnesite, respectively. The best calcination temperatures were used to prepare composites at different ratios of 1:2:3, 2:3:1 and 3:2:1, bauxite: gypsum: magnesite respectively. All the ratios gave low sulphate and iron as impurities within the recommended standards. The composites lowered fluoride concentration level to 1.53 mg/L, 2.07 mg/L, 2.60 mg/L for 1:2:3, 2:3:1, 3:2:1 ratios, respectively. In conclusion the study reveals that, it is possible for composites made of adsorbent calcinated at different optimum temperatures to give good results in fluoride removal from drinking water, as well as standard pH, iron and sulphate values in treated water.

scholarly journals Sodium Hypochlorite Treatment: The Impact on Bacteria and Endotoxin Concentrations in Drinking Water Pipes of A Pig Nursery

Agriculture ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 86
Author(s):  
Regina Böger ◽  
Karl Rohn ◽  
Nicole Kemper ◽  
Jochen Schulz
Keyword(s):  
Water Quality ◽  
Drinking Water ◽  
Sodium Hypochlorite ◽  
Coliform Bacteria ◽  
Treated Water ◽  
Water Pipes ◽  
Pseudomonas Spp ◽  
Untreated Water ◽  
The Impact ◽  
Total Bacteria

Poor drinking water quality can affect pigs’ health and performance. The disinfection of water may enhance microbial water quality. In this study, bacteria and endotoxins in sodium hypochlorite-treated and -untreated water from one pig nursery were analyzed. Water samples were taken from incoming water and from compartments with treated and untreated water at the beginning and end of pipes and from nipples. The farm was visited 14 times to measure total bacteria counts and concentrations of Pseudomonas spp. and endotoxins. Additionally, the occurrence of coliform bacteria was analyzed. A mixed model analysis revealed significant reductions in total bacteria counts and Pseudomonas spp. in treated water at the beginning of pipes and at nipple drinkers. The differences between bacteria concentrations at the end of pipes had no clear trend. Endotoxin concentrations were approximately equal at the beginning of pipes and at nipple drinkers but were found to have differences at the end of pipes. The occurrence of coliform bacteria was significantly reduced in treated water. The application of sodium hypochlorite can significantly reduce bacteria in water pipes. Endotoxin concentrations were mostly unaffected by water treatment. Disinfection of the dead-end pipe sections failed, and thus these parts should be regarded as potential contamination sources.

scholarly journals Examination of Surface Water Along River-Rima Floodplain in Wamakko, Sokoto State, Nigeria.

2020 ◽  
Vol 2 (3) ◽  
Author(s):  
Abdulqadir Abubakar Usman ◽  
Murtala Abubakar Gada ◽  
Aminu Muhammad Bayawa ◽  
Ibrahim Mustapha Dankani ◽  
Saadu Umar Wali
Keyword(s):  
Drinking Water ◽  
Surface Water ◽  
Principal Component ◽  
Hierarchical Cluster ◽  
World Health ◽  
Coliform Bacteria ◽  
Municipal Sewage ◽  
Bacteria Growth ◽  
Anthropogenic Inputs ◽  
Health Organization

This study examined the hydrochemistry of surface water along the River-Rima floodplain area. Five sampling locations were purposively selected, and, in each point, three samples were taken from surface water (river). The sampling was repeated after 20 days. Thus, a total of 30 samples were collected. Water samples obtained were subjected to laboratory tests. Results revealed that BOD, TDS, Mg2+, and Fe3+ are above the World Health Organization (WHO) and Standard Organization of Nigeria (SON) reference guidelines for drinking water quality. Isolates detected from the coliform bacteriological analysis include Enterobacter aerogene, Escherichia coli, and Citrobacter freundii with most of the samples showing coliform bacteria growth above the SON standard for drinking water. Hence, the water in the River-Rima floodplain of the Wamakko area is of low quality and unsafe for drinking. Results of principal component analysis (PCA) revealed external influences such as pollutant wash off and rock weathering as controls on hydrochemistry of surface water. There is some indication of anthropogenic inputs (Cl-, NO3-, and PO42-) based on hierarchical cluster analysis. Elements including Cl-, NO3-, and PO42- are increasingly added into surface water from human activities, mainly agriculture, and municipal sewage.

scholarly journals Construction and testing of a drinking water disinfection and filtration system for developing nations

2020 ◽  
Vol 15 (1) ◽  
pp. 33-53
Author(s):  
Joshua Seaberg ◽  
Paul Weckler ◽  
Joshua Ringer ◽  
Gregory Wilber
Keyword(s):  
Drinking Water ◽  
Surface Water ◽  
Developing Nations ◽  
Water Disinfection ◽  
Coliform Bacteria ◽  
Sand Filter ◽  
Filtration System ◽  
Drinking Water Disinfection ◽  
Electrolysis System

Abstract –A drinking water disinfection and filtration system was designed using inexpensive and accessible materials. The prototype was constructed from two barrels and a pump that circulated water through a gravity sand filter before injection with locally-generated chlorine produced through saline electrolysis. System turbidity reduction and disinfection effectiveness was determined using surface water from -----. Ninety gallons of water showed a 70% reduction in turbidity and no coliform bacteria were detected after ninety minutes of operation. The system was built for less than $900 (2017) and is safe, simple, and reliable.

Lab scale study on electrocoagulation defluoridation process optimization along with aluminium leaching in the process and comparison with full scale plant operation

2011 ◽  
Vol 63 (12) ◽  
pp. 2788-2795 ◽  
Author(s):  
Poonam Gwala ◽  
Subhash Andey ◽  
Vasant Mhaisalkar ◽  
Pawan Labhasetwar ◽  
Sarika Pimpalkar ◽  
...  
Keyword(s):  
Drinking Water ◽  
Process Optimization ◽  
Current Density ◽  
Fluoride Concentration ◽  
Full Scale ◽  
Experimental Results ◽  
Fluoride Removal ◽  
Electrode Polarization ◽  
Operational Conditions ◽  
Aluminium Leaching

An excess or lack of fluoride in drinking water is harmful to human health. Desirable and permissible standards of fluoride in drinking water are 1.0 and 1.5 mg/L, respectively, as per Indian drinking water quality standards i.e., BIS 10500, 1991. In this paper, the performance of an electro-coagulation defluoridation batch process with aluminium electrodes was investigated. Different operational conditions such as fluoride concentration in water, pH and current density were varied and performance of the process was examined. Influence of operational conditions on (i) electrode polarization phenomena, (ii) pH evolution during electrolysis and (iii) the amount of aluminium released (coagulant) was investigated. Removal by electrodes is primarily responsible for the high defluoridation efficiency and the adsorption by hydroxide aluminium floc provides secondary effect. Experimental data obtained at optimum conditions that favored simultaneous mixing and flotation confirmed that concentrations lower than 1 mg/L could be achieved when initial concentrations were between 2 and 20 mg/L. pH value was found to be an important parameter that affected fluoride removal significantly. The optimal initial pH range is between 6 and 7 at which effective defluoridation and removal efficiencies over 98% were achieved. Furthermore, experimental results prominently displayed that an increase in current density substantially reduces the treatment duration, but with increased residual aluminium level. The paper focuses on pilot scale defluoridation process optimization along with aluminium leaching and experimental results were compared with a full-scale plant having capacity of 600 liter per batch.

Fluoride removal from drinking water in Senegal: laboratory and pilot experimentation on bone char-based treatment

2011 ◽  
Vol 1 (4) ◽  
pp. 213-223 ◽  
Author(s):  
Sabrina Sorlini ◽  
Daniela Palazzini ◽  
Carlo Collivignarelli
Keyword(s):  
Drinking Water ◽  
Dental Fluorosis ◽  
Low Cost ◽  
Fluoride Concentration ◽  
Pilot Scale ◽  
Appropriate Technology ◽  
World Health ◽  
Fluoride Removal ◽  
Process Conditions ◽  
Bone Char

In Senegal there are four regions where fluoride concentration in drinking water exceeds the World Health Organization guide value of 1.5 mg/L. This generates permanent damages to the teeth (dental fluorosis) and to the skeleton (skeletal fluorosis). A safe, efficient, simple and low-cost effective defluoridation technique is not available yet and needs to be developed in order to prevent the occurrence of fluorosis. This experimental research was carried out in order to define an appropriate technology for fluoride removal from groundwater in Senegal. Batch tests and filtration tests at laboratory and pilot scale were carried out using animal bone char as adsorbent material for fluoride removal. Possible influencing parameters, such as specific ions in Senegalese drinking water, were investigated and the best process conditions were defined for the application in Senegal. The results attest to the efficacy of bone char in removing fluoride from Senegalese water: at pilot scale the mean specific adsorption was 2.7 mg F−/g of bone char, corresponding to a total treated volume of 4,000 L and a filter life of nearly three months.

scholarly journals Isolation of Fluoride Resistant Microorganisms from Fluoride Contaminated Ground Water Samples of Nalgonda District and their role in Bioremediation

2021 ◽  
Vol 18 (1) ◽  
pp. 107-112
Author(s):  
Thirumala Mothe ◽  
Patnam Umashankar ◽  
Vishnuvardhan Reddy Sultanpuram
Keyword(s):  
Ground Water ◽  
Fluoride Concentration ◽  
Luria Bertani ◽  
Resistant Bacteria ◽  
Fluoride Removal ◽  
Batch Mode ◽  
Two Samples ◽  
High Fluoride Concentration ◽  
High Fluoride ◽  
Nalgonda District

Consuming of water contaminated with high fluoride concentration for a very long time causes health problems such as, dental and skeletal fluorosis. Hence, defluoridation of water is essentially required before consumption, when water is contaminated with high fluoride concentration. In this present study, research was focussed on to isolate bacteria which are showing fluoride resistantance from samples of ground water from high fluoride affected regions of Nalgonda. After analysis of 10 samples from different areas of Nalgonda district, two samples of ground water from Narketpally and Nampally showed the high fluoride concentrations of 9.18 ppm and 7.55 ppm respectively. Hence, in the present study, Narketpally ground water sample with highest ppm was considered to isolate fluoride resistant bacteria. A total of eight fluoride resistant organisms were purified from this sample with varying fluoride resistance on Luria Bertani agar with varying fluoride concentraion from 25mg/L to 600mg/L at pH 7. Among the eight strains isolated, three strains MB1, F and G were showing high fluoride resistance (up to 500mg/L), which were further explored for their role in bioremediation of fluoride. In batch mode study, MB1 strain showed high fluoride degradation of 68%, whereas, F and G strains showed 57% and 44%fluoride removal, respectively, when fluoride concentration was present at 20 mgL-1 at 30 °C temperature and pH 7, with dextrose (10 g) utilised as source of carbon per 100 mL media after incubation of 8 days. Results indicate that, MB1 possibly a potential fluoride resistant bacterium with high fluoride bioremediation capacity.

Particle and microorganism removal in floating plastic media coupled with microfiltration membrane for surface water treatment

2005 ◽  
Vol 51 (10) ◽  
pp. 93-100 ◽  
Author(s):  
C. Chiemchaisri ◽  
W. Chiemchaisri ◽  
T. Kornboonraksa ◽  
C. Dumrongsukit ◽  
S. Threedeach ◽  
...  
Keyword(s):  
Water Treatment ◽  
Surface Water ◽  
Filtration Rate ◽  
Coliform Bacteria ◽  
Transmembrane Pressure ◽  
Raw Water ◽  
Microfiltration Membrane ◽  
Treated Water ◽  
Surface Water Treatment ◽  
Plastic Media

Floating plastic media followed by hollow fiber microfiltration membrane was applied for surface water treatment. The performance of the system in terms of particle and microorganisms was investigated. The floating filter was examined at different filtration rates of 5, 10 and 15 m3/m2.h. Treated water was then fed into a microfiltration unit where different filtration rates were examined at 0.6, 1.0 and 1.4 m3/m2.d. It was found that polyaluminum chloride was the best coagulant for the removal of particle, algae and coliform bacteria. Average turbidity in treated water from the floating plastic media filter was 3.3, 12.2 and 15.5 NTU for raw water of 80 NTU and 12.9, 11.7 and 31.2 NTU for raw water of 160 NTU after 6 hours at the filtration rates of 5, 10 and 15 m3/m2.h, respectively. The microfiltration unit could further reduce the turbidity to 0.2–0.5 NTU with low transmembrane pressure development of 0.3–3.7 kPa. Microfiltration membrane could retain most of algae and coliform bacteria remaining in the effluent from the pretreatment unit. It was found that at higher turbidity, algae and coliform bacteria removal efficiencies were achieved at lower filtration rate of the system of 5 m3/m2.h whereas a higher filtration rate of 15 m3/m2.h yielded better coliphage removal.

scholarly journals Detection of enteric viruses in Hungarian surface waters: first steps towards environmental surveillance

2013 ◽  
Vol 11 (4) ◽  
pp. 772-782 ◽  
Author(s):  
Anita Kern ◽  
Mihaly Kadar ◽  
Katalin Szomor ◽  
György Berencsi ◽  
Beatrix Kapusinszky ◽  
...  
Keyword(s):  
Drinking Water ◽  
Surface Water ◽  
Surface Waters ◽  
Membrane Filtration ◽  
Virus Detection ◽  
Water Concentration ◽  
Water Quality Monitoring ◽  
Health Concern ◽  
Human Pathogens ◽  
Bathing Waters

Waterborne viruses infect the human population through the consumption of contaminated drinking water and by direct contact with polluted surface water during recreational activity. Although water related viral outbreaks are a major public health concern, virus detection is not a part of the water quality monitoring scheme, mainly due to the absence of routine analysis methods. In the present study, we implemented various approaches for water concentration and virus detection, and tested on Hungarian surface water samples. Eighty samples were collected from 16 sites in Hungary. Samples were concentrated by glass wool and membrane filtration. Human adenoviruses were detected by conventional and quantitative real-time polymerase chain reaction (PCR) methods in 56% (45/80) of the samples; viral titers ranged from 8.60 × 101 to 3.91 × 104 genome copies per liter. Noroviruses and enteroviruses were detected in 30% (24/80) and 13% (10/80) of samples, respectively, by reverse transcription-PCR assays. Results indicate a high prevalence of viral human pathogens in surface waters, suggesting the necessity of a detailed survey focusing on the quality of natural bathing waters and drinking water sources.

scholarly journals Vulnerability of Drinking-Water Wells in La Crosse, Wisconsin, to Enteric-Virus Contamination from Surface Water Contributions

2004 ◽  
Vol 70 (10) ◽  
pp. 5937-5946 ◽  
Author(s):  
Mark A. Borchardt ◽  
Nathaniel L. Haas ◽  
Randall J. Hunt
Keyword(s):  
Drinking Water ◽  
Surface Water ◽  
River Water ◽  
Water Samples ◽  
Hepatitis A Virus ◽  
Enteric Viruses ◽  
Coliform Bacteria ◽  
Well Water ◽  
Rt Pcr ◽  
Water Wells

ABSTRACT Human enteric viruses can contaminate municipal drinking-water wells, but few studies have examined the routes by which viruses enter these wells. In the present study, the objective was to monitor the municipal wells of La Crosse, Wisconsin, for enteric viruses and determine whether the amount of Mississippi River water infiltrating the wells was related to the frequency of virus detection. From March 2001 to February 2002, one river water site and four wells predicted by hydrogeological modeling to have variable degrees of surface water contributions were sampled monthly for enteric viruses, microbial indicators of sanitary quality, and oxygen and hydrogen isotopes. 18O/16O and 2H/1H ratios were used to determine the level of surface water contributions. All samples were collected prior to chlorination at the wellhead. By reverse transcription-PCR (RT-PCR), 24 of 48 municipal well water samples (50%) were positive for enteric viruses, including enteroviruses, rotavirus, hepatitis A virus (HAV), and noroviruses. Of 12 river water samples, 10 (83%) were virus positive by RT-PCR. Viable enteroviruses were not detected by cell culture in the well samples, although three well samples were positive for culturable HAV. Enteroviruses detected in the wells by RT-PCR were identified as several serotypes of echoviruses and group A and group B coxsackieviruses. None of the well water samples was positive for indicators of sanitary quality, namely male-specific and somatic coliphages, total coliform bacteria, Escherichia coli, and fecal enterococci. Contrary to expectations, viruses were found in all wells regardless of the level of surface water contributions. This result suggests that there were other unidentified sources, in addition to surface water, responsible for the contamination.

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