• Journal of Environmental Science International
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• v.23 no.9
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• pp.1655-1662
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• 2014

A comprehensive fractionation technique was applied to a set of water samples obtained along drinking water treatment process with ozonation and biological activated carbon (BAC) process to obtain detailed profiles of dissolved organic matter (DOM) and to evaluate the haloacetic acid (HAA) formation potentials of these DOM fractions. The results indicated that coagulation-sedimentation-sand filtration treatment showed limited ability to remove hydrophilic fraction (28%), while removal of hydrophobic and transphilic fraction were 57% and 40%, respectively. And ozonation and BAC treatment showed limited ability to remove hydrophobic fractions (6%), while removal of hydrophilic and transphilic fractions were 25% and 18%. The haloacetic acid formation potential (HAAFP)/dissolved organic carbon (DOC) of hydrophilic fraction was the highest along the treatment train and HAAFP/DOC of hydrophilic fraction was higher than hydrophobic and transphilic fraction as 23%~30%, because of better removal for hydrophobic fraction both in concentration and reactivity.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.12
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• pp.1321-1326
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• 2005

As a results of this research, the Nakdong River consisted of 43% of hydrophobic fraction, 39% of hydrophilic fraction, and 18% of transphilic fraction. The hydrophobic fraction in this raw water was mostly fulvic acid. Fulvic acid comprised of 62% and the rest was humic acid(38%). There was more carboxylic acid functional roup(64%) than phenolic group(36%). HPI-N and HPI-C comprised of 17% and 22% in the hydrophilic portion, respectively. The results of the membrane fouling test using UF membrane according to NOM fractions. HPI-N caused more fouling than HPI-C. Humic acid caused more fouling than fulvic acid probably due to higher adsorption capacity. Since humic acid has higher adsorption capacity than fulvic acid, it would be more adsorbed onto the membrane pores. The carboxylic acid functional group caused more fouling than the phenolic group.

• Journal of Korean Society of Water and Wastewater
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• v.24 no.2
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• pp.237-246
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• 2010

This study was carried out to compare the performances of hydrophobic and hydrophilic membranes in the filtration of the pretreatment waters using coagulants such as PAC and PAHCs, and to investigate the influence of NOM characteristics on the fouling of membranes. As a result, the hydrophobic fraction was more effectively removed by PAHCs, however the transphilic and hydrophilic fraction were more effectively removed by PAC on NOM removal. Raw water showed the highest response in the range of humic substances, and pre-coagulated waters with PAC and PAHCs followed. It was also observed that the fouling effect for a hydrophobic membrane was greater than that of a hydrophilic membrane with a similar pore size, due to fouling caused by adsorption. Foulants causing significant flux decline were alcoholic compounds (polysaccharide-like) and humic substances including aromatic groups. Especially, it appeared that alcoholic compounds such as polysaccharide-like substances which mostly remained after coagulation pretreatment had most influence on fouling. It was found that fouling were influenced by each fraction NOM components depending on coagulants used. And PAHCs was more efficient for membrane fouling than PAC.

• Journal of Korean Society on Water Environment
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• v.30 no.1
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• pp.80-86
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• 2014

Unlike to natural organic matters (NOMs), effluent organic matters (EfOMs) are not well understood due to their complexity and heterogeneity. In this study, EfOMs from sewage and industrial wastewater treatment effluents and Suwannee River NOM (SRNOM) were isolated into hydrophobic (HPO), transphilic (TPI) and hydrophilic (HPI) fractions. Specific ultraviolet absorbance (SUVA) and fluorescence excitation emission matrix (FEEM) analyses were used to characterize physicochemical properties. In addition, acute toxicity and oxidative stress to Daphnia magna were evaluated to characterize toxicological properties. EfOMs showed similar properties to microbially derived organic matters having low hydrophobicity, which are totally different from SRNOM having high hydrophobicity. Moreover, acute toxicity and antioxidant enzyme activity in D. magna was largely dependent on fraction types of EfOMs. These findings suggest that EfOMs have different physicochemical and toxicological properties compared with those of NOMs, which needs to be further identified with various sources of EfOMs.

• 한국생물공학회:학술대회논문집
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• 2003.04a
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• pp.334-338
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• 2003

In this study, We evaluated the removal efficiency of natural organic matters(NOM) in the Ultrafiltration(UF) and Nanofiltration(NF) membranes with molecular weight cutoff of 2500(GH), 8000(GM) and 250(HL), respectively. Filtration type was cross-flow filtration. The investigation result about raw water structure was hydrophobic 28%, hydrophilic 53% and transphilic 19%, in conjunction with XAD8/4 resin fractionation method. We were compared with UF(GM, GH) and NF(HL), in operation characteristic. In spite of poor MWCO, GM(8000Da) was superior than GH(2500Da), in the efficiency of total operation. It was showed the NF(HL) 80%, UF(GM) 50%, in the removing efficiency of HAAFP.

• Journal of Korean Society of Environmental Engineers
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• v.36 no.9
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• pp.604-608
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• 2014

This study investigated influence of dissolved organic nitrogen (DON) in natural organic matter (NOM) on the formation of organic chloramines upon monochloramination. Ratios of dissolved organic carbon (DOC) to DON of the 16 NOM isolates ranged from 7 to 47 mg-C/mg-N. Levels of organic chloramines maxed in 24 hours at $0.16mg-Cl_2/mg-N$ in average. The yields were relatively lower, but decay of organic chloramines were slower than those upon chlorination. Organic chloramines formed upon monochloramination decreased by 56% in average in 120 h. NOM with lower DOC/DON ratios formed more organic chloramines. NOM fractions such as hydrophobic, hydrophilic, transphilic, and colloidal did not significantly impact formation of organic chloramines. As the monochloramine doses increased, more organic chloramines were produced ($R^2=0.91$). Overestimation of disinfection capacity due to the formation of organic chloramines may not be concerns for monochloramine systems since only 6% of monochloramine could be converted to organic chloramines upon monochloramination of NOM.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.10
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• pp.1031-1037
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• 2006

The main purposes of this study were to compare the characteristics of fractionated natural organic matters(NOM) from Han River water and Wangsuk(W) stream water, and to investigate the relationships between NOM and the formation of disinfection by products(DBPs). Three types of resin such as XAD-4, XAD-7HP and IRC-50 were used to isolate the water samples into three organic fractions. The DOC concentrations of raw waters were relatively low($1.5{\sim}3.3$ mg/L) at all seasons. The hydrophilic was the major constituent, contributing $44{\sim}63%$ of the total NOM and hydrophobic $21{\sim}33%$, transphilic $16{\sim}31%$, respectively. The formation of trihalomethans(THMs) was highly influenced by particulated NOM especially in the rainy season, whereas haloaceticacid forming potentials(HAAFPs) depended more on the hydrophilic fraction of dissolved NOM which is known to be difficult to be removed through conventional processes. The NOM of W stream was characterized as 15% hydrophobic, 9% transphilic, and 76% hydrophilic. In the fractionation of NOM using resins, $20{\sim}40%$ of the NOM in W tributary water could not be clearly isolated, whereas, 85% of the NOM in the raw water was recovered. Although the DOC concentration of tributary water was higher than the raw waters from the Han River, the DBPFPs was approximately 40% of the raw waters. In DBPFPs aspect, W stream has less effect than Han River water itself. Bromide in tributary waters discharged from waste water treatment plants has been found to shift the distribution of THMs and HANs to the more brominated DBPs.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.10
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• pp.1047-1053
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• 2008

This study was to evaluate the optimum conditions for chemical coagulation to remove color from the effluent of a piggery wastewater treatment process. The DOC concentration in the effluent was about 227.3 mg/L, color was 2,430 CU, turbidity was 22.1 NTU, and UV$_{254}$-absorbance was 3.7 cm$^{-1}$. The fractions of hydrophobic, transphilic, and hydrophilic substance of the effluent was about 55.3%, 17.4%, 27.3% respectively. Also, molecular weight cut-off(MWCO) of below 0.5 K, 0.5 K to 1 K, 1 K to 10 K, 10 K to 30 K, and over 30 K were 74.2%, 7.3%, 5.5%, 7.1%, and 5.9% respectively. SCD(streaming current Detector) was used to find out the optimum pH values and coagulant dosages. The optimum dosages and pH of Al$^{3+}$ were 5.84 mM and 5.3, while those of Fe$^{3+}$ were 9.25 mM and 5.0, respectively. At optimum conditions of coagulation, color removal efficiencies for aluminium sulfate and ferric chloride were as high as 91.9 and 98.7%, respectively. Chemical coagulation showed good performance to remove color from on biologically treated piggery wastewater.

• Korean Journal of Environmental Biology
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• v.34 no.1
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• pp.48-55
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• 2016

This study investigates the effect of effluent organic matter (EfOM) from sewage wastewater treatment plants on estrogenic activity reduction of bisphenol A (BPA) by UV photolysis. The EfOM and Suwannee River natural organic matter (SR-NOM) as reference were isolated into hydrophobic (HPO), transphilic (TPI) and hydrophilic (HPI) fractions depending on polarity. The specific ultraviolet absorbance (SUVA) analysis indicated that EfOM showed similar properties to microbially derived organic matters with low hydrophobicity, which is different from SR-NOM having high hydrophobicity. UV irradiation upto 3 hr significantly reduced SUVA values of both EfOM and SR-NOM (p<0.0001), depending on the polarity of organic matters. In the absence of organic matters, the relative estrogenic activity (REA) of BPA ($5.0{\times}10^{-5}M$) was decreased from 86% to 63% by UV photolysis (2 hr). However, the decrease of mean REA was from 68% to 37% in the presence of organic matters, which was significantly independent on the type (EfOM or SR-NOM) and polarity (HPO, TPI or HPI) of organic matters (p>0.05). As a result, the reduced REA by UV photolysis of BPA with and without organic matters was 31% and 23%, respectively, suggesting that both EfOM and SR-NOM accelerated the photolytic reduction of BPA estrogenic activity.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.10
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• pp.1046-1054
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• 2006

The raw water DOC contained 39.3% of hydrophilics, 42.9% of hydriophobic, and 17.8% of transphilic. The hydrophobic fraction in this raw water was mostly fulvic acid. Fulvic acid comprised of 62% and the rest was humic acid(38%). There was more carboxylic acid functional group(64%) than phenolic group(36%). HPI-N and HPI-C comprised of 17% and 22% in the hydrophilic portion, respectively. The fouling mechanisms on the membrane surface and into its porous structure were analyzed in terms of several kinetic models. In order to analyze the fouling kinetics, the various kinetic models described in this paper were used to fit the experimental results. The kinetic models and kinetic constants obtained for each operation condition. The permeate flux was rapidly declined by simultaneous pore blocking and cake formation. Also, the permeate flux declined with decreasing internal pore size resulted from organic deposition into the membrane pore. The results of the membrane fouling test using UF membrane according to NOM fractions. HPI-N caused more fouling than HPI-C. Humic acid caused more fouling than fulvic acid probably due to higher adsorption capacity. Since humic acid has higher adsorption capacity than fulvic acid, it would be more adsorbed onto the membrane pores.