Drinking Water Treatment Research Papers (original) (raw)

One concern with current techniques of UV reactor validation is that they provide only a measure of the mean UV fluence. In this research, the actual fluence distribution of a UV reactor is measured through the use of photochemically... more

One concern with current techniques of UV reactor validation is that they provide only a measure of the mean UV fluence. In this research, the actual fluence distribution of a UV reactor is measured through the use of photochemically active fluorescent microspheres. ...

This is the first publication on arsenic contamination of the Red River alluvial tract in the city of Hanoi and in the surrounding rural districts. Due to naturally occurring organic matter in the sediments, the groundwaters are anoxic... more

This is the first publication on arsenic contamination of the Red River alluvial tract in the city of Hanoi and in the surrounding rural districts. Due to naturally occurring organic matter in the sediments, the groundwaters are anoxic and rich in iron. With an average arsenic ...

This study assessed the levels of some physicochemical parameters of borehole water samples from Bindawa local government area of Katsina State. The water samples were collected from Doro, Shibdawa, Tama, Agalawa and analyzed for heavy... more

This study assessed the levels of some physicochemical parameters of borehole water samples from Bindawa local government area of Katsina State. The water samples were collected from Doro, Shibdawa, Tama, Agalawa and analyzed for heavy metals (Cd, Fe, Pb, Cr & Cu) using AAS, while physicochemical parameters were determined using standard analytical methods.

Catalytic liquid-phase hydrogenation of aqueous nitrate solutions is presented as a potential, advanced treatment technology for the removal of excessive quantities of nitrate ions from polluted drinking water streams. Catalysts are... more

Catalytic liquid-phase hydrogenation of aqueous nitrate solutions is presented as a potential, advanced treatment technology for the removal of excessive quantities of nitrate ions from polluted drinking water streams. Catalysts are briefly reviewed first, followed by mechanistic speculations and kinetics that have been proposed for the liquid-phase nitrate reduction. Subsequently, a novel process scheme consisting of integrated ion-exchange and catalytic

Global incidence of primary amoebic meningoencephalitis cases associated with domestic drinking water is increasing. The need for understanding disinfectant regimes capable of eliminating the causative microorganism, Naegleria fowleri,... more

Global incidence of primary amoebic meningoencephalitis cases associated with domestic drinking water is increasing. The need for understanding disinfectant regimes capable of eliminating the causative microorganism, Naegleria fowleri, from bulk water and pipe wall biofilms is critical. This field study demonstrated the successful elimination of N. fowleri from the bulk water and pipe wall biofilm of a persistently colonised operational drinking water distribution system (DWDS), and the prevention of further re-colonisation. A new chlorination unit was installed along the pipe line to boost the free chlorine residual to combat the persistence of N. fowleri. Biofilm and bulk water were monitored prior to and after re-chlorination (RCl), pre-rechlorination (pre-RCl) and post-rechlorination (post-RCl), respectively , for one year. A constant free chlorine concentration of > 1 mg/L resulted in the elimination of N. fowleri from both the bulk water and biofilm at the post-RCl site. Other amoeba species were detected during the first two months of chlorination, but all amoebae were eliminated from both the bulk water and biofilm at post-RCl after 60 days of chlorination with free chlorine concentrations > 1 mg/L. In addition, a dynamic change in the biofilm community composition and a four log reduction in biofilm cell density occurred post-RCl. The pre-RCl site continued to be seasonally colonised by N. fowleri, but the constant free chlorine residual of > 1 mg/L prevented N. fowleri from recolonising the bulk and pipe wall biofilm at the post-RCl site. To our knowledge, this is the first study to demonstrate successful removal of N. fowleri from both the bulk and pipe wall biofilm and prevention of re-colonisation of N. fowleri in an operational DWDS. The findings of this study are of importance to water utilities in addressing the presence of N. fowleri and other amoeba in susceptible DWDSs.

It is claimed that India has already achieved the Millennium Development Goal (MDG) water target, but the article shows how India's tribal women walk the longest distances to fetch drinking water for their families. The article is... more

It is claimed that India has already achieved the Millennium Development Goal (MDG) water target, but the article shows how India's tribal women walk the longest distances to fetch drinking water for their families. The article is written in a statistical analysis style to give an overview of problems faced by tribal women in connection with drinking water. Published on the International Women's Day, the article argues India’s tribal women and women of other socially excluded groups certainly need a much better treatment if India wishes to follow a path of equitable growth.

The current inadequate drinking water services and sanitation problems have incited the need for a better management strategy by the country's water and sanitation organizations. In this study, a logical review of the water supply and... more

The current inadequate drinking water services and sanitation problems have incited the need for a better management strategy by the country's water and sanitation organizations. In this study, a logical review of the water supply and sanitation origin and management structures was done to suggest a plausible management option in Nigeria. The paper also revealed that the overall management practices of these organizations at the three tiers of governments (federal, states and local) is very poor and uncoordinated which have resulted in low level of water and sanitation coverage. Thus, in order to ameliorate these problems, the study recommends sector wide reforms with the aim of radical improvement in the management processes of these organizations. Other proposed improvement strategies include: private sector participation, effective and reasonable tariff regime for effective cost recovery, increment in political support and leadership commitment, introduction of benchmarking a...

An electro-coagulation-flotation process has been developed for water treatment. This involved an electrolytic reactor with aluminium electrodes and a separation/flotation tank. The water to be treated passed through the reactor and was... more

An electro-coagulation-flotation process has been developed for water treatment. This involved an electrolytic reactor with aluminium electrodes and a separation/flotation tank. The water to be treated passed through the reactor and was subjected to coagulation/flotation, by Al(III) ions dissolved from the electrodes, the resulting flocs floating after being captured by hydrogen gas bubbles generated at cathode surfaces. Apparent current efficiencies for Al dissolution as aqueous Al(III) species at pH 6.5 and 7.8 were greater than unity. This was due to additional reactions occurring in parallel with Al dissolution: oxygen reduction at anodes and cathodes, and hydrogen evolution at cathodes, resulting in net (i.e. oxidation + reduction) currents at both anodes and cathodes. The specific electrical energy consumption of the reactor for drinking water treatment was as low as 20 kWh (kg Al)(-1) for current densities of 10-20A m(-2). The water treatment performance of the electrocoagulation process was found to be superior to that of conventional coagulation with aluminium sulphate for treating a model-coloured water, with 20% more dissolved organic carbon (DOC) being removed for the same Al(III) dose. However, for a lowland surface water sample, the two processes achieved a similar performance for DOC and UV-absorbance removal. In addition, an up-flow electrocoagulator configuration performed better than a horizontal flow configuration, with both bipolar and monopolar electrodes.

In the framework of liquid treatment processes, with the aim of ensuring public health security for drinking water or to prevent economic damage, when safeguarding important production processes, major investments have been devoted to... more

In the framework of liquid treatment processes, with the aim of ensuring public health security for drinking water or to prevent economic damage, when safeguarding important production processes, major investments have been devoted to research, study and design of innovative products able to respond to market demands, that offer nowadays several solutions. The present work focuses, specifically, on the filtration of drinking water with filter cartridge systems, with the aim to investigate the effect of their introduction into a hydraulic system in terms of head losses. The problem is particularly important when the cartridge is installed in hydraulic plants characterized by low pressures, in which its insertion can make the pressure levels fall below the minimum limit recommended to ensure the smooth operation of domestic devices. Specifically, the behavior of seven different commercial filter cartridges was analyzed through an experimental analysis conducted in a pilot circuit at t...

Drinking water supply in Egypt is based on surface water abstraction (91.4 %), groundwater (8.3 %) and desalination (0.24 %). As Egypt is currently facing problems with the pollution of surface water by industrial, agricultural and... more

Drinking water supply in Egypt is based on surface water abstraction (91.4 %), groundwater (8.3 %) and desalination (0.24 %). As Egypt is currently facing problems with the pollution of surface water by industrial, agricultural and municipal inflows, riverbank filtration would offer a low cost alternative for pre-treatment of raw water for potable use. The objective of this paper is to evaluate the potential of riverbank filtration in Egypt based on drilling at potential sites and monitoring of both water level and water quality parameters. The evaluation of six sites receiving a bank filtration share of more than 50 % and producing drinking water has proven the feasibility of riverbank filtration in Egypt. Favorable hydrogeological conditions exist both along the river Nile in Upper Egypt and on main canals in the desert fringes. Key issues for the feasibility of riverbank filtration in Egypt were found to be the hydraulic connection between surface waters and the adjacent aquifer and the landside groundwater quality. The river Nile in Upper Egypt has fully to partially cut through surficial clayey sediments and is in hydraulic connection with a Quaternary aquifer that is comprised of sandy riverine sediments. The sandy riverbed and coarse aquifer materials have a sufficient hydraulic conductivity for riverbank filtration. Islands and stretches of the river channel that have convex sides are favorable for siting RBF schemes to receive a high portion of bank filtrate and limit mixing with land-side groundwater, which contains high concentrations of iron and manganese. The main benefits of RBF would be the removal of pathogens, algae and turbidity. It is recommended that wells are constructed at short distances from the river bank, to get a high share of bank filtrate.

Coagulation is the most important stage in drinking water treatment processes for the maintenance of acceptable treated water quality and economic plant operation, which involves many complex physical and chemical phenomena. Moreover,... more

Coagulation is the most important stage in drinking water treatment processes for the maintenance of acceptable treated water quality and economic plant operation, which involves many complex physical and chemical phenomena. Moreover, coagulant dosing rate is non-linearly correlated to raw water characteristics such as turbidity, conductivity, pH, temperature, etc. As such, coagulation reaction is hard or even impossible to control satisfactorily by conventional methods. Traditionally, jar tests are used to determine the optimum coagulant dosage. However, this is expensive and time-consuming and does not enable responses to changes in raw water quality in real time. Modelling can be used to overcome these limitations. In this study, an Adaptive Neuro-Fuzzy Inference System (ANFIS) was used for modelling of coagulant dosage in drinking water treatment plant of Boudouaou, Algeria. Six on-line variables of raw water quality including turbidity, conductivity, temperature, dissolved oxygen, ultraviolet absorbance, and the pH of water, and alum dosage were used to build the coagulant dosage model. Two ANFIS-based Neuro-fuzzy systems are presented. The two Neuro-fuzzy systems are: (1) grid partition-based fuzzy inference system (FIS), named ANFIS-GRID, and (2) subtractive clustering based (FIS), named ANFIS-SUB. The low root mean square error and high correlation coefficient values were obtained with ANFIS-SUB method of a first-order Sugeno type inference. This study demonstrates that ANFIS-SUB outperforms ANFIS-GRID due to its simplicity in parameter selection and its fitness in the target problem.

10 different papers and authors in Climate Change qualitative research for mitigation and adaption as part of the Phd in Climate Change and Sustainabiloity at University of San Carlos of Guatemala. Climatology. Water , Hidrology. Risk and... more

10 different papers and authors in Climate Change qualitative research for mitigation and adaption as part of the Phd in Climate Change and Sustainabiloity at University of San Carlos of Guatemala. Climatology. Water , Hidrology. Risk and disaters, Nanpotechnology for water filtration. Sustainability.

BACKGROUND: When direct current (DC) is used in electrocoagulation processes, an impermeable oxide layer may form on the cathode and corrosion of the anode may occur due to oxidation. This prevents effective current transfer between the... more

BACKGROUND: When direct current (DC) is used in electrocoagulation processes, an impermeable oxide layer may form on the cathode and corrosion of the anode may occur due to oxidation. This prevents effective current transfer between the anode and cathode, so the efficiency of the electrocoagulation process declines. These disadvantages of DC have been reduced by adopting alternating current (AC). The main objective of this study is to investigate the effects of AC and DC on the removal of fluoride from water using an aluminum alloy as anode and cathode.RESULTS: Results showed that removal efficiencies of 93 and 91.5% with energy consumption of 1.883 and 2.541 kWh kL−1 was achieved at a current density of 1.0 A dm−2 and pH 7.0 using an aluminum alloy as electrodes using AC and DC, respectively. For both AC and DC, the adsorption of fluoride fitted the Langmuir adsorption isotherm. The adsorption process follows second-order kinetics and temperature studies showed that adsorption was exothermic and spontaneous in nature.CONCLUSIONS: The aluminum hydroxide generated in the cell removed the fluoride present in the water and reduced it to a permissible level thus making it drinkable. It is concluded that an alternating current prevents passivation of the aluminum anode during electrocoagulation and avoids the additional energy wasted due to the resistance of the aluminum oxide film formed on the anode surface. Copyright © 2010 Society of Chemical Industry

Natural organic matter (NOM) represents a range of soluble and insoluble material which can have considerable impact on drinking water quality. In addition to creating problems with taste, odour, clarification, and colour, removal of NOM... more

Natural organic matter (NOM) represents a range of soluble and insoluble material which can have considerable impact on drinking water quality. In addition to creating problems with taste, odour, clarification, and colour, removal of NOM is problematic because it can initiate the formation of disinfection by-products, which can adversely affect human health. Numerous technologies and methods have been employed to remove NOM in water treatment, with the most common processes involving the use of coagulants and similar technologies. This paper provides an overview of the most widely studied coagulants, coagulant aids, dual coagulants, and alternative coagulants. The paper also investigates the effects of operating parameters such as temperature, coagulant dose, pH, use of inorganic salts, inorganic polymeric coagulants, and organic polyelectrolytes in terms of charge neutralisation, polymer adsorption, and polymer bridging. Finally, emerging technologies and the use of novel coagulants are investigated.