Chlorination by-products

Endocrine disrupting compounds and their chlorination by-products are two classes of emerging contaminants. Surface water and wastewater treatment technologies have limitations in removing these contaminants. This study evaluated the ability of non-imprinted polymer particles (NIP) to remove the endocrine disruptor 17β-estradiol (E2) and its chlorination by-products from water and wastewater. NIP effectively removed 98% of 10 mg/L E2 from wastewater. NIP were also effective in removing chlorination by-products of E2 by 84.9% after 10 mg/L E2 in water was chlorinated at 5 mg/L. In the presence of 5 mg/L humic acid, NIP were able to achieve removal of 10 mg/L E2 by greater than 99.9%. Furthermore, after chlorination of 10 mg/L E2 and 5 mg/L humic acid at 10 mg/L chlorine, NIP were also able to remove the chlorination by-products formed as well as the remaining E2 by greater than 99.9%. The presence of 5 mg/L humic acid did not adversely affect the adsorption efficiency. The results of this research indicate that NIPs have good potential as a final treatment step for surface water and wastewater treatment.

Endocrine disrupting compounds and their chlorination by-products are two classes of emerging contaminants. Surface water and wastewater treatment technologies have limitations in removing these contaminants. This study evaluated the ability of non-imprinted polymer particles (NIP) to remove the endocrine disruptor 17β-estradiol (E2) and its chlorination by-products from water and wastewater. NIP effectively removed 98% of 10 mg/L E2 from wastewater. NIP were also effective in removing chlorination by-products of E2 by 84.9% after 10 mg/L E2 in water was chlorinated at 5 mg/L. In the presence of 5 mg/L humic acid, NIP were able to achieve removal of 10 mg/L E2 by greater than 99.9%. Furthermore, after chlorination of 10 mg/L E2 and 5 mg/L humic acid at 10 mg/L chlorine, NIP were also able to remove the chlorination by-products formed as well as the remaining E2 by greater than 99.9%. The presence of 5 mg/L humic acid did not adversely affect the adsorption efficiency. The results of...

Sodium hypochlorite (NaOCl) is widely used to disinfect seawater in power plant cooling systems in order to reduce biofouling, and in ballast water treatment systems to prevent transport of exotic marine species. While the toxicity of NaOCl is expected to increase by ongoing ocean acidification, and many experimental studies have shown how algal calcification, photosynthesis and growth respond to ocean acidification, no studies have investigated the relationship between NaOCl toxicity and increased CO 2. Therefore, we investigated whether the impacts of NaOCl on survival, chlorophyll a (Chl-a), and effective quantum yield in three marine phytoplankton belonging to different taxonomic classes are increased under high CO 2 levels. Our results show that all biological parameters of the three species decreased under increasing NaOCl concentration, but increasing CO 2 concentration alone (from 450 to 715 μatm) had no effect on any of these parameters in the organisms. However, due to the synergistic effects between NaOCl and CO 2 , the survival and Chl-a content in two of the species, Thalassiosira eccentrica and Heterosigma akashiwo, were significantly reduced under high CO 2 when NaOCl was also elevated. The results show that combined exposure to high CO 2 and NaOCl results in increasing toxicity of NaOCl in some marine phytoplankton. Consequently, greater caution with use of NaOCl will be required, as its use is widespread in coastal waters.

The use of seawater for industrial cooling is a vital technology that poses some of the most profound environmental impact on the water quality in the Arabian Gulf. Biocide (chlorine) is added to the seawater to control biofouling of the cooling system. This added chlorine reacts with bromide and other chemicals naturally exist in the water to form a wide range of oxidants. Regrettably, reactions between the residual oxidants and natural organic matter in the water lead to formation of toxic halogenated organic compounds that have detrimental effects on the environment when they are dis-charged into the Gulf. This paper describes the formation of trihalomethanes (THMs) in seawater cooling systems. Re-sults of kinetic experiments have shown that concentrations of THMs increased rapidly with time during the first half hour. Chlorination of seawater has shown significant increase in total THMs (TTHMs) and in bromoform concentra-tions. Rapid decrease of UV absorbance at 254 nm was also ...

Endocrine disrupting compounds and their chlorination by-products are two classes of emerging contaminants. Surface water and wastewater treatment technologies have limitations in removing these contaminants. This study evaluated the ability of non-imprinted polymer particles (NIP) to remove the endocrine disruptor 17β-estradiol (E2) and its chlorination by-products from water and wastewater. NIP effectively removed 98% of 10 mg/L E2 from wastewater. NIP were also effective in removing chlorination by-products of E2 by 84.9% after 10 mg/L E2 in water was chlorinated at 5 mg/L. In the presence of 5 mg/L humic acid, NIP were able to achieve removal of 10 mg/L E2 by greater than 99.9%. Furthermore, after chlorination of 10 mg/L E2 and 5 mg/L humic acid at 10 mg/L chlorine, NIP were also able to remove the chlorination by-products formed as well as the remaining E2 by greater than 99.9%. The presence of 5 mg/L humic acid did not adversely affect the adsorption efficiency. The results of...

The use of seawater for industrial cooling is a vital technology that poses some of the most profound environmental impact on the water quality in the Arabian Gulf. Biocide (chlorine) is added to the seawater to control biofouling of the cooling system. This added chlorine reacts with bromide and other chemicals naturally exist in the water to form a wide range of oxidants. Regrettably, reactions between the residual oxidants and natural organic matter in the water lead to formation of toxic halogenated organic compounds that have detrimental effects on the environment when they are dis-charged into the Gulf. This paper describes the formation of trihalomethanes (THMs) in seawater cooling systems. Re-sults of kinetic experiments have shown that concentrations of THMs increased rapidly with time during the first half hour. Chlorination of seawater has shown significant increase in total THMs (TTHMs) and in bromoform concentra-tions. Rapid decrease of UV absorbance at 254 nm was also ...

The use of seawater for industrial cooling is a vital technology that poses some of the most profound environmental impact on the water quality in the Arabian Gulf. Biocide (chlorine) is added to the seawater to control biofouling of the cooling system. This added chlorine reacts with bromide and other chemicals naturally exist in the water to form a wide range of oxidants. Regrettably, reactions between the residual oxidants and natural organic matter in the water lead to formation of toxic halogenated organic compounds that have detrimental effects on the environment when they are dis-charged into the Gulf. This paper describes the formation of trihalomethanes (THMs) in seawater cooling systems. Re-sults of kinetic experiments have shown that concentrations of THMs increased rapidly with time during the first half hour. Chlorination of seawater has shown significant increase in total THMs (TTHMs) and in bromoform concentra-tions. Rapid decrease of UV absorbance at 254 nm was also ...

The generation, monitoring, and health impacts of disinfection by-products (DBPs) in potable water are problems of worldwide worry. Several nations, besides the World Health Organization, possess regulations and/or guidelines on bearable levels of DBPs in water. Since drinking water is frequently remediated using a chemical killing agent, DBPs are pollutants to which several humans are unprotected. On account of the health impacts linked to subjection to chlorinated water and/or some DBPs, the water manufacturing has performed great endeavors to equilibrate killing pathogens and DBP monitoring. Large survey has been realized on rising DBPs of health and regulatory worry. In spite of the fact that the attention on DBPs was previously on chlorine-and bromine-containing carbonaceous DBPs, appearing DBPs comprise iodine-containing species, also halogenated and non-halogenated nitrogenous DBPs. In addition, latest toxicity experimentation has proposed that certain of the more recent PBPs are of more elevated toxicity than some of the regulated chemical products. Therefore, survey has been realized to better comprehend how to costeffectively monitor a large interval of regulated and appearing DBPs. This comprises the usage of advanced remediation and killing pathogens methodologies. This paper shows certain of the newest research works at comprehending these significant DBP-related problems. Disinfection is killing microorganisms present in water; but, it is as well killing human beings drinking water by poisonous DBPs. Using chemicals for water treatment is finally a lost cause.

There were two new water sources were identified in Greater Cairo. Ain Alhaya is one of the most common springs that are subjected to continuous increase in the ground water level. Ain El-Khiala is a greenish brown spring located to the south of Ain El-Sira. During the present study, samples were collected from these regions and compared to quality of water collected from River Nile, Ismailia Canal and tap water (chlorinated treated water). The physicochemical parameters, disinfection by-products (DBPs) were measured in the collected samples in addition to microbiological examination. It was showed that quality of water was the same in River Nile and Ismailia Canal. The disinfection by chlorination is effective in water treatment and enhanced the water quality as compared to the other different sourced water although it gives various by-products. As regard to the springs, it was noticed that water quality is highly better in Ain Alhaya than Ain El-Khiala. The study concluded that there were statistical correlations among the physico-chemical, microbiological and organic measurements in different sourced water as compared to river nile and the most significant correlations were noticed among microbiological and organic measurements.

This work aims to study the physicochemical and biological parameters of Boukerdene Dam's water and treated water at different steps of the treatment processes in Sidi-Amar's Station (Tipaza, Algeria) with a particular interest to the phytoplankton. This work is also related to the demonstration of the enhanced coagulation (EC) process as an efficient method in algae and organic matter (OM) removal from surface water by its application in jar tests. The diversity of the phytoplankton shows the presence of 21 genera comprising 30 algae species out of 8 samples taken from the Boukerdene Dam. Among the identified genera, seven of them are responsible for the unpleasant tastes and odours of water; six others are responsible for filter fouling. Generally, the conventional drinking water treatment processes employed at this water treatment plant shows a limited efficiency of OM and algae removal. The novelty of this work is that the jar tests of EC (pH 6 and alum dose 15 mg L-1) as only one stage of water treatment, without chlorination and filtration, improve the removal of OM and algae at 97 to 99%, respectively.

This review paper deals with the formation of disinfection by-products (DBPs). Water basin remains a wonderful chemical reactor that allows the occurrence of intricate secondary disinfection chemical reactions, forming several hundreds of DBPs at the same time with microorganisms killing. The kinetics of DBPs formation is tightly dependent on water physicochemical characteristics such as temperature, hydrophobic/hydrophilic fractions in natural organic matter (NOM), pH, and pretreatment. Reducing DBPs levels in drinking water is not a relevant measure as the newly-developed analytical techniques and the health-related research reveal that the tolerable DBPs' levels must be further decreased and would be detected at ng L-1 instead of μg L-1 scale. Furthermore, because of the fact that man is being exposed to DBPs concentrations in drinking water in his lifetime, there will be a cumulative effect of these toxic chemical products even at their more reduced concentrations. Hence, the removal of these chemical products is sought for and is considered a real challenge and the main objective of water treatment technology for mankind survival.

Electrocoagulation (EC) process has been largely found efficient in terms of pathogens removal. This literature
review focuses on describing the key killing microorganisms' pathway followed throughout the EC technique. The pathogens
removal route using EC is deeply assessed following the practical experimentation realized during these last years. Physical
elimination and chemical deactivation pathways are suggested for bacteria reduction procedure throughout the EC method
employing Fe/Al anodes: (1) entrapping pathogens in flocs, (2) destabilizing negatively charged microbes through sweep
flocculation, and (3) demobilizing bacteria cell envelopes upon electrochemically formed reactive oxygen species or direct
impact of the electric field. Finally, deepest investigation works on microbes’ removal through EC are more called to promote the
industrial applications of this performant technology.

There is no doubt that the chemical water treatment has resolved the problem of drinking water supply for several decades to humankind especially in terms of pathogen microorganisms and turbidity removal. However, due to chemicals used through this treatment and increasing quantities of pollutants discharged into nature, numerous health problems have been largely more and more proved and reported. This review discusses the toxicity of chlorine, alum, and polyelectrolyte which are widely employed through the world. The main addressed question here is: When the true and radical water treatment technology will be really and definitely applied? There is no water treatment technique but only distillation process which is successfully applied at the largest scale in nature by God. At least, physical processes such as membrane processes should be more and more applied through water treatment plants for reducing chemicals use. Most of chlorination disadvantages may be avoided through a better understanding of the mutual actions conducting to the generation of chlorine by-products and the use of more sophisticated procedures to assess toxicity capacity of such chemicals. Finally, this study arrives at its time since the Environmental Engineers and the Green Chemistry specialists have largely opened the discussion about polluting industry and preserving nature. Returning Man to its initial and noble Mission on Earth is reflected through this research to preserve both humankind and nature.

The generation, monitoring, and health impacts of disinfection by-products (DBPs) in potable water are problems of worldwide worry. Several nations, besides the World Health Organization, possess regulations and/or guidelines on bearable levels of DBPs in water. Since drinking water is frequently remediated using a chemical killing agent, DBPs are pollutants to which several humans are unprotected. On account of the health impacts linked to subjection to chlorinated water and/or some DBPs, the water manufacturing has performed great endeavors to equilibrate killing pathogens and DBP monitoring. Large survey has been realized on rising DBPs of health and regulatory worry. In spite of the fact that the attention on DBPs was previously on chlorine-and bromine-containing carbonaceous DBPs, appearing DBPs comprise iodine-containing species, also halogenated and non-halogenated nitrogenous DBPs. In addition, latest toxicity experimentation has proposed that certain of the more recent PBPs are of more elevated toxicity than some of the regulated chemical products. Therefore, survey has been realized to better comprehend how to cost-effectively monitor a large interval of regulated and appearing DBPs. This comprises the usage of advanced remediation and killing pathogens methodologies. This paper shows certain of the newest research works at comprehending these significant DBP-related problems. Disinfection is killing microorganisms present in water; but, it is as well killing human beings drinking water by poisonous DBPs. Using chemicals for water treatment is finally a lost cause.

Since the 1970s' disinfection by-products (DBPs) detection, the water treatment specialists' main focuses were accorded to the DBPs formation, characterization, regulations and control. Involved stages in disinfection process were at a certain level kept at the side as a black box. This paper is a broad review on chlorination applied in water treatment technology especially in terms of involved mechanisms. Chlorine occasions significant injury to bacterial cells, cell permeability dislocation and nucleic acids and enzymes injury. Hypochlorous acid oxidizes sulfhydryl groups, harms iron-sulfur centers, deactivates nutrient transport, hinders cell respiration, and deteriorates the capacity of cells to keep a sufficient adenylate energy charge to stay viable. All disinfectants are highly efficient killing agents. However, these chemical products are very toxic by their selves. Moreover, they interact with NOM, microorganisms, and algae to produce DBPs which are as well poisonous. Consequently, the use of disinfectants must be avoided upon using physical processes or at least reduced as possible at the lowest level.

This study investigates the microalgae removal from Ghrib Dam water by electroflotation (EF) using stainless steel electrodes. The results obtained show that EF is excellent in microalgae
removal (~100%). The effects of parameters such as: current density (i), initial pH and distance between electrodes (d) are examined. The optimal conditions are: i = 170 Am−2 and
d = 1 cm during 15 min at pH 7.8. Future research must focus on microalgae lysis, toxin release and degradation due to EF treatment. Precautions must be taken such as reducing
the applied voltage, increasing the residence time in the electrochemical device and adding
a powdered activated carbon adsorption stage.