Use of silicate by-products in water treatment processes and development of eco-friendly self-polishing antifouling coatings

Following the successful implementation of the ‘MAC21’ Project, the ‘New MAC21’ Project is being implemented for further development of membrane technology in Japan. The project includes various pilot-scale and laboratory experiments on 1) nanofiltration system, and 2) MF/UF system combined with advanced treatment processes such as activated carbon treatment, ozonation and biological treatment. As the result, it has been shown that both systems are applicable to drinking water treatment. Although a NF system was very effective for the removal of organic contaminants such as precursors of disinfection by-products, it is considered that the development of a proper treatment method for the concentrate will be very important in the future.

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Variation of Disinfection By-Products Formation Potential Species at Several Stages of Drinking Water Treatment Plants

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.777.337 ◽

2013 ◽

Vol 777 ◽

pp. 337-340

Author(s):

Qiang Zhang ◽

Bin Liu

Keyword(s):

Drinking Water ◽

Water Treatment ◽

Drinking Water Treatment ◽

Biological Activated Carbon ◽

Formation Potential ◽

Treatment Processes ◽

Water Treatment Plants ◽

Microbial Products ◽

Water Plants ◽

By Products

The variation of disinfection by-products (DBPs) at several stages of drinking water treatment plants was investigated in two drinking water plants. The results clearly indicate that the low molecular weight total organic carbon (TOC) which has been identified as primary precursor for chlorinated DBPs was difficult to remove by coagulation. Plant A which used conventional coagulation/sedimentation could not decrease the species of trihalomethanes (THMs) and haloacetic acids (HAAs) formation potential. Biological activated carbon (BAC) was applied in Plant B which removed the maximum amount of TOC, while more kinds of microbial products were produced in BAC unit which could be the potential precursors of DBPs. Therefore, the species of DBPs formation potential still increased in the treatment processes of Plant B. Because different components of organic precursors produced different DBPs species, the processes of Plant B could decrease TOC efficiently but the species of THMs and HAAs formation potential.

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The control of disinfection by-products precursors by advanced methods of water treatment

Water Science & Technology Water Supply ◽

10.2166/ws.2018.012 ◽

2018 ◽

Vol 18 (6) ◽

pp. 1906-1914

Author(s):

Mariola Rajca ◽

Agnieszka Włodyka-Bergier ◽

Michał Bodzek

Keyword(s):

Organic Matter ◽

Water Treatment ◽

Natural Organic Matter ◽

Membrane Processes ◽

Lower Affinity ◽

Treatment Processes ◽

Hydrophilic Fraction ◽

Specific Potential ◽

Hydrophobic Fraction ◽

By Products

Abstract In the article, the results of the research on reactivity of natural organic matter in regard to disinfection by-products, specifically trihalomethanes (THM) formation, with the use of model waters, are discussed. Additionally, the evaluation of different processes used in water treatment, i.e. photocatalysis, MIEX®DOC and membrane processes, is made. It was found that the affinity of particular natural organic matter compounds to form chlorination by-products could be arranged in a series: hydrophobic fraction (HA) > hydrophilic fraction (FA). The applied treatment processes efficiently decreased the concentration of disinfection by-products (DBPs) precursors and characterized with different removal mechanisms. Water treated by means of photocatalysis (specific potential of ∑THM was 30 μg/mg dissolved organic carbon (DOC) for HA and 12 μg/mg DOC for FA) revealed lower affinity to form chlorination by-products in comparison with water undergone to MIEX®DOC process (specific potential of ∑THM was 38 μg/mg DOC for HA and 29 μg/mg DOC for FA). Moreover, combination of those methods with membrane processes efficiently reduced DBPs formation potential. In nanofiltration effluents DBPs potential were very low and equalled to 50 μg/L for HA and 15 μg/L for FA.

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Characterization of Disinfection By-Products Levels at an Emergency Surface Water Treatment Plant in a Refugee Settlement in Northern Uganda

Water ◽

10.3390/w11040647 ◽

2019 ◽

Vol 11 (4) ◽

pp. 647 ◽

Cited By ~ 3

Author(s):

Syed Ali ◽

Matt Arnold ◽

Frederick Liesner ◽

Jean-Francois Fesselet

Keyword(s):

Water Treatment ◽

Surface Water ◽

Standard Treatment ◽

Treatment Plant ◽

Water Treatment Plant ◽

Northern Uganda ◽

Surface Water Treatment ◽

Treatment Processes ◽

By Products ◽

Rapid Treatment

The reliance on chlorination in humanitarian operations has raised concerns among practitioners about possible health risks associated with disinfection by-products; however, to date, there has not been an evaluation of disinfection by-product (DBP) levels in an emergency water supply intervention. This study aimed to investigate DBP levels at a surface-water treatment plant serving a refugee settlement in northern Uganda using the colorimetric Hach THM Plus Method. The plant had two treatment processes: (1) Simultaneous clarification–chlorination (“rapid treatment”); and (2) pre-clarification and chlorination in separate tanks (“standard treatment”). For both standard (n = 17) and rapid (n = 3) treatment processes, DBP levels in unique parcels of water were tested at 30 min post-chlorination and after 24 h of storage (to simulate what refugees actually consume). DBP levels after 24 h did not exceed the World Health Organization (WHO) guideline limit of 300 ppb equivalent chloroform, either for standard treatment (mean: 85.1 ppb; 95% confidence interval (C.I.): 71.0–99.1 ppb; maximum: 133.7 ppb) or for rapid treatment (mean: 218.0 ppb; 95% C.I.: 151.2–284.8; maximum: 249.0 ppb). Observed DBPs levels do not appear to be problematic with respect to the general population, but may pose sub-chronic exposure risks to specifically vulnerable populations that warrant further investigation.

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Natural Organic Matter and Disinfectant By-Products (DBPs) Formation Potential in Agriculture Area in Malaysia

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.802.513 ◽

2015 ◽

Vol 802 ◽

pp. 513-518

Author(s):

Nurazim Ibrahim ◽

Hamidi Abdul Aziz ◽

Mohd Suffian Yusoff

Keyword(s):

Organic Matter ◽

Water Treatment ◽

Natural Organic Matter ◽

Distribution System ◽

Water Distribution ◽

Water Distribution System ◽

Treatment Plant ◽

Water Treatment Plant ◽

Treatment Processes ◽

By Products

Natural organic matter (NOM) in water reacts with chlorine or other disinfectants and form hazardous disinfectant by-products (DBPs). This study aimed to detect the presence of NOM in a conventional water distribution system using UV absorbance at 254 nm as a surrogate. Two water treatment plants were selected, namely, Jalan Baharu Water Treatment Plant (JBWTP) and Lubok Buntar Water Treatment Plant (LBWTP). Aside from determining the amount of NOM, the reduction of UV254after completing the series of treatments (coagulation, flocculation, sedimentation, filtration, and disinfection) was also observed. The presence of UV254in both raw water and treated water samples confirmed the presence of NOM. The concentration of UV254recorded at JBWTP and LBWTP were 0.14 and 0.13 cm−1, respectively. After the treatment processes, the concentration was reduced to 0.04 cm−1for JBWTP and 0.03 cm−1for LBWTP. These results indicated that the water supply in both plants contains DBP precursors and implied the possibility of DBP formation in the system. Moreover, the percentage reduction of UV254recorded were 69% and 75% for JBWTP and LBWTP, respectively.

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