scholarly journals REMOVAL OF NATURAL ORGANIC MATTER USING ELECTROCOAGULATION AS A FIRST STEP FOR DESALINATION OF BRACKISH WATER

2011 ◽  
Vol 11 (1) ◽  
pp. 103-107
Author(s):  
Wasinton Simanjuntak ◽  
Irwan Ginting ◽  
Kamisah D. Pandiangan

In the present study, electrocoagulation method was employed to remove natural organic matter from brackish water. This study explores the potential of brackish water as a source of potable water. Two electrochemical variables, potential and contact time, were tested to determine their effect on the treatment efficiency defined in terms of the reduction of the absorbance at the wavelength of 254 nm (A254). Both potential and contact time were found to influence the removal efficiency of the method, and the best result was obtained from the experiment using the potential of 8 V and contact time of 60 min, resulting in 69.5% reduction of the absorbance. Very clean treated water was produced with much lower conductivity (12.06 mS/cm) as compared to that obtained for the sea water sample from a location near to the sampling site (133.9 mS/cm).

2019 ◽  
Vol 22 (3) ◽  
pp. 85-92 ◽  
Author(s):  
Aulia Rahma ◽  
Muthia Elma ◽  
Mahmud Mahmud ◽  
Chairul Irawan ◽  
Amalia Enggar Pratiwi ◽  
...  

The high number of natural organic matter contain in wetland water may cause its water has brown color and not consumable. In other hand, intrusion of sea water through wetland aquifer create water become saline, notably on hot season. Coagulation is effective method to applied for removing of natural organic matter. However, it could not be used for salinity removal. Hence combination of coagulation and pervaporation process is attractive method to removing both of natural organic matter and conductivity of wetland saline water. The objective of this works is to investigate optimum coagulant doses for removing organic matter by coagulation process as pretreatment and to analysis performance of coagulation-pervaporation silica-pectin membrane for removing of organic matter and conductivity of wetland saline water. Coagulation process in this work carried out under varied aluminum sulfate dose 10-60 mg.L-1. Silica-pectin membrane was used for pervaporation process at feed temperature ~25 °C (room temperature). Optimum condition of pretreatment coagulation set as alum dose at 30 mg.L-1 with maximum removal efficiency 81,8 % (UV254) and 40 % (conductivity). In other hand, combining of coagulation-pervaporation silica-pectin membrane shows both of UV254 and salt rejection extremely good instead without pretreatment coagulation of 86,8 % and 99,9 % for UV254 and salt rejection respectively. Moreover, water flux of silica-pectin membrane pervaporation with coagulation pretreatment shown higher 17,7 % over water flux of wetland saline water without pretreatment coagulation. Combining of coagulation and pervaporation silica-pectin membrane is effective to removing both of organic matter and salinity of wetland saline water at room temperature.


Water ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 2935
Author(s):  
Ning Zhang ◽  
Beihai Zhou ◽  
Rongfang Yuan ◽  
Fei Wang ◽  
Huilun Chen

Trimethoprim (TMP) is often used for the treatment of various bacterial infections. It can be detected in water, and it is difficult to be biodegraded. In this study, the degradation mechanism of TMP through ozonation and the effect of humic acids (HA) were investigated. Excessive ozone (pH 6, 0 °C) could reduce the content of TMP to less than 1% in 30 s. However, when ozone (O3) was not excessive (pH 6, 20 °C), the removal efficiency of TMP increased with the increase of O3 concentration. Four possible degradation pathways of TMP in the process of ozonation were speculated: hydroxylation, demethylation, carbonylation, and cleavage. The presence of HA in water inhibit the generation of ozonation products of TMP. The excitation-emission matrices (EEM) analysis showed that with the extension of ozonation time, the fluorescence value in the solution decreased and the fluorescence peak blue shifted. These results indicated that the structure of HA changed in the reaction and was competitively degraded with TMP. According to the free radical quenching test, the products of pyrolysis, direct hydroxylation and demethylation were mainly produced by indirect oxidation.


2013 ◽  
Vol 779-780 ◽  
pp. 1383-1387 ◽  
Author(s):  
Samia Achour ◽  
Saadia Guergazi

The aim of this work is to study effect of two powerful oxidants (potassium permanganate and chlorine) on natural organic matter in surface waters. Trials are conducted out with three Algerian surface waters under controlled experimental conditions (oxidant dose applied and contact time). Permanganate was used alone in the first step, while the combination permanganate-chlorine was used in the second step.As for chlorine demand, permanganate consumption seems correlated with physicochemical characteristics of waters and particularly the nature and content of organic matter. The effect of a coupling preoxidation by permanganate / post-chlorination resulted in a decrease of chlorine consumption and amounts of produced trihalomethanes.


2011 ◽  
Vol 63 (10) ◽  
pp. 2427-2433 ◽  
Author(s):  
R. H. Peiris ◽  
H. Budman ◽  
C. Moresoli ◽  
R. L. Legge

Identifying the extent of humic acid (HA)-like and fulvic acid (FA)-like natural organic matter (NOM) present in natural water is important to assess disinfection by-product formation and fouling potential during drinking water treatment applications. However, the unique fluorescence properties related to HA-like NOM is masked by the fluorescence signals of the more abundant FA-like NOM. For this reason, it is not possible to accurately characterize HA-like and FA-like NOM components in a single water sample using direct fluorescence EEM analysis. A relatively simple approach is described here that demonstrates the feasibility of using a fluorescence excitation-emission matrix (EEM) approach for identifying HA-like and FA-like NOM fractions in water when used in combination with a series of pH adjustments and filtration steps. It is demonstrated that the fluorescence EEMs of HA-like and FA-like NOM fractions from the river water sample possessed different spectral properties. Fractionation of HA-like and FA-like NOM prior to fluorescence analysis is therefore proposed as a more reasonable approach.


Ground Water ◽  
2016 ◽  
Vol 55 (3) ◽  
pp. 316-326 ◽  
Author(s):  
Abdullah H. A. Dehwah ◽  
Samir Al-Mashharawi ◽  
Kim Choon Ng ◽  
Thomas M. Missimer

2014 ◽  
Vol 2 (1) ◽  
pp. 1
Author(s):  
Eny Heriani R.N. ◽  
Wasinton Simanjuntak ◽  
Ilim .

This study was carried out to investigate treatment of brackish water using a combination of electrocoagulation and adsorption using carbosil prepared from rice husk with pyrolysis method. Electrocoagulation was applied with the aim to remove natural organic matter in the sample, using aluminim as electrodes, with the particular purpose to study the effect of potenstials.For this purpose, electrocoagulation experiments were conducted at potential of 4, 6, and 8 volt at fixed contact time of 60 minutes.The performance of the method was defined in term of absorbance reduction at the wavelengths of 254 and 285 nm, since the absorbance at these two wavelenghts was found to correlate well with the amount of organic matter in the water samples. The treated water was then subjected to adsorption process at different contac times of 5. 10, and 15 minutes, and the performance of the process was evaluated in term of electrical conductivity reduction.The results obtained indicate that for electrocoagulation process, the higest reduction of natural organic matter content was achieved using potential of 8 volt, and adsorption porcess of 15 minutes was found to result in reduction of electrical conductivity from 15.13 mS/cm to 10.10 mS/cm.Characterization of the carbosil using SEM/EDX technique revealed that the carbosil has practically homogeneous surface and able to adsorb salt and several other elements from the brackish water. Key words : adsorption, brackish water, carbosil, electrocoagulation


2012 ◽  
Vol 47 (2) ◽  
pp. 131-139 ◽  
Author(s):  
Vanessa Borraro ◽  
Rémi Riopel ◽  
François Caron ◽  
Stefan Siemann

Fluorescence spectroscopy with the spectral resolution routine PARAFAC is a leading tool to analyze Natural Organic Matter (NOM) in waters. This routine resolves spectra into humic-, fulvic- and protein-like components, which helps interpret the NOM dynamics in environmental systems. This work is one of the first systematic studies dealing with the impact of chemical perturbations on the fluorescence spectral interpretation of NOM. The samples, taken at two Canadian Shield locations (a shallow set and a deep set to ∼650 m), were perturbed for pH (‘titrations’ from pH 4 to 10) and salinity (from ∼0.02 to 3‰ salt content), then analyzed by fluorescence/PARAFAC. Our fluorescence signals for the three components showed no clear change with pH, as would be expected with a classic titration. The signals were reproducible between replicates for the humic- and protein-like components, but less so for the fulvic-like components. Changes of salinity only had a small impact on the fluorescence signal (a ∼2.7–3.4% signal decrease for each salinity unit, ‰) for the three components in this salinity range.


2019 ◽  
Vol 68 (7) ◽  
pp. 523-534 ◽  
Author(s):  
Shivam Snehi ◽  
Hariraj Singh ◽  
Tanwi Priya ◽  
Brijesh Kumar Mishra

Abstract In the present study, the concept of ‘Sample alteration of surface water’ has been employed to improve the efficiency of the aluminum-based electrocoagulation (EC) treatment method for the removal of reactive fractions of natural organic matter (NOM) from chlorinated water. The characteristics of surface water have been slightly modified by adding mine water in different ratios. The process has been optimized using the response surface methodology (RSM) considering pH, current density, mix ratio, and contact time as factors. At the optimized condition, the EC method has significantly reduced total organic carbon, dissolved organic carbon (DOC), and UV254 absorbance values up to 24%, 27%, and 80%, respectively. The cumulative impact of sample alteration and EC method has exhibited outstanding coagulant activity in terms of UV254 abs, DOC, turbidity, phenol, and absorbance slope index (ASI) as well. A decrease in ASI values indicated the reduction of trihalomethane's formation in water-containing chlorine. This was validated by reduced chlorine demand. It can be concluded that mixing mine water with surface water can be a feasible and efficient method for treating water with a high NOM content.


2000 ◽  
Vol 42 (1) ◽  
pp. 53-66 ◽  
Author(s):  
Gregory V Korshin ◽  
John F Ferguson ◽  
Alice N Lancaster

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