• Journal of Korean Society of Water and Wastewater
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• v.28 no.1
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• pp.61-72
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• 2014

Study on effluent organic matter (EfOM) characteristic and removal efficiency is required, because EfOM is important in regard to the stability of effluents reuse, quality issues of artificial recharge and water conservation of aqueous system. UV technology is widely used in wastewater treatment. Many reports have been conducted on microbial disinfection and micro pollutant reduction with UV treatment. However, the study on EfOM with UV has limited because low/medium pressure UV lamp is not sufficient to affect refractory organics. The high intensity of pulsed UV would mineralize EfOM itself as well as change the characteristics of EfOM. Chlorine demand and DBPs formation is affected on the changed amounts and properties of EfOM. The objective of this study is to investigate the effect on EfOM, chlorine residual, and chlorinated DBPs formation with low pressure and pulsed UV treatment. The removal of organic matter through low pressure UV treatment is insignificant effect. Pulsed UV treatment effectively removes/transforms EfOM. As a result, the chlorine consumption is changed and chlorine DBPs formation is decreased. However, excessive UV treatment caused problems of increasing chlorine consumption and generating unknown by-products.

• Journal of Korean Society of Water and Wastewater
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• v.37 no.5
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• pp.253-259
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• 2023

Bioreactors are devices used by sewage treatment plants to process sewage and which produce active sludge, and sediments separated by solid-liquid are treated in anaerobic digestion tanks. In anaerobic digestion tanks, the volume of active sludge deposits is reduced and biogas is produced. After dehydrating the digestive sludge generated after anaerobic digestion, anaerobic digested wastewater, which features a high concentration of organic matters, is generated. In this study, the decomposition of organic carbon and nitrogen was studied by advanced oxidation process. Ozone-microbubble flotation process was used for oxidation pretreatment. During ozonation, the TOC decreased by 11.6%. After ozone treatment, the TOC decreased and the removal rate reached 80.4% as a result of the Ultra Violet-Advanced Oxidation Process (UV-AOP). The results with regard to organic substances before and after treatment differed depending on the organic carbon index, such as CODMn, CODCr, and TOC. Those indexes did not change significantly in ozone treatment, but decreased significantly after the UV-AOP process as the linkage treatment, and were removed by up to 39.1%, 15.2%, and 80.4%, respectively. It was confirmed that biodegradability was improved according to the ratio of CODMn to TOC. As for the nitrogen component, the ammonia nitrogen component showed a level of 3.2×10² mg/L or more, and the content was maintained at 80% even after treatment. Since most of the contaminants are removed from the treated water and its transparency is high, this water can be utilized as a resource that contains high concentrations of nitrogen.

• Journal of Korean Society on Water Environment
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• v.29 no.5
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• pp.674-680
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• 2013

Basic studies for the treatment of particulate organic substances contained in wastewater by flotation have been conducted. Four kinds of plastics were chosen as the possibly existing organic particles in wastewater and the Zisman plots for these substances were constructed by measuring the contact angle of liquids on their surfaces. The critical surface tensions for these organic substances were estimated based on the constructed Zisman plot and the floatability of organic substances were regarded to be related with their molecular structure. The existence of dissolved organic substances such as a surfactant was observed to affect the extent of flotation of particulate organics. In addition, the consideration of work of adhesion was thought to be better than adopting the critical surface tension as the analytical basis in the operational design of flotation process of organic particles.

• Journal of Korean Society on Water Environment
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• v.25 no.5
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• pp.674-681
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• 2009

Characteristics of organic matters (OM) in wastewater and the removal efficiencies were investigated using the influent and the effluent samples collected from 21 wastewater treatment plants. The OM characteristics investigated included biodegradability, humic content, specific UV absorbance (SUVA), the distribution percentage of refractory OM (R-OM), and synchronous fluorescence spectra. The types of wastewater (sewage, livestock waste/night soils, industrial waste) were easily distinguished by comparing the synchronous fluorescence spectra of the influent wastewater. The prominent peak of protein-like fluorescence (PLF) was observed for livestock waste/night soils whereas sewage exhibited a unique fluorescence peak at a wavelength of 370 nm. Irrespective of the wastewater types, the distribution percentage of R-OM increased from the influent to the effluent. Livestock waste/night soils showed the highest removal efficiency among all the three types of wastewater. There was no statistical difference of the removal efficiency between a traditional activated sludge and biological advanced treatment processes. Removal efficiency based on dissolved organic carbon DOC presented good correlations with the distribution percentage of R-OM and fulvic-like fluorescence (FLF) of the influent. The prediction for DOC removal efficiency was improved by using multiple regression analyses based on some selected OM characteristics and mixed liquid suspended solid (MLSS).

• Journal of the Korean GEO-environmental Society
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• v.8 no.3
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• pp.5-10
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• 2007

The paper presents results of qualitative analysis of non-regulated organic pollutants in municipal wastewater and treated municipal wastewater with flocculation, ozone and UV process using GC-MS. The majority of the pollutants in the influent of the municipal wastewater treatment facility were either food related or due to the diffuse discharge from products used both in households and in industry. In the case of biological treatment process removed some organic pollutants effectively. But some organic pollutants were not removed with biological treatment. Thus, additional steps to improve the quality of effluent municipal wastewater will require a more rigorous control of consumer products used in household and municipal wastewater process using advanced treatment processs. The obtained data contributed to the evaluation of pollutants discharges to the ecosystem as well as to the characterization of pollution sources in the basin.

• Journal of Industrial and Engineering Chemistry
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• v.67
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• pp.175-186
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• 2018

Carbon nanomaterials (CNMs), particularly carbon nanotube and graphene-based materials, are rapidly emerging as one of the most effective adsorbents for wastewater treatment. CNMs hold great potential as new generation adsorbents due to their high surface to volume ratio, as well as extraordinary chemical, mechanical and thermal stabilities. However, implementation of pristine CNMs in real world applications are still hindered due to their poor solubility in most solvents. Hence, surface modification of CNMs is essential for wastewater treatment application in order to improve its solubility, chemical stability, fouling resistance and efficiency. Numerous studies have reported the applications of functionalized CNMs as very promising adsorbents for treating organic and inorganic wastewater pollutants. In this paper, the removal of organic dye and phenol contaminants from wastewater using various type of functionalized CNMs are highlighted and summarized. Challenges and future opportunities for application of these CNMs as adsorbents in sustainable wastewater treatment are also addressed in this paper.

• Journal of Wetlands Research
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• v.17 no.4
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• pp.421-427
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• 2015

In ASM model, organic matters are classified according to their characteristics and general classification into COD and BOD cannot satisfy conditions required by ASM. In this study, it was performed to study classification of organic matters required by ASM on the basis of microorganisms' respiration rate subject to wastewater and sludge treatment. As results of analysis of the organic matter's appearance, it was found that there were some differences in composition of organic matters between wastewaters. It is considered that it is an important characteristic of wastewater that should be understood in treating wastewater in each process. Therefore, it is considered that appearance of organic matters in each wastewater identified by this study will be used as important basic data for operation of municipal wastewater treatment plant. It was identified that SS was an important factor affecting nitrification through organic matter and ammonium nitrogen change analysis according to reaction time in the nitrification. It is considered that the nitrification has close relationship with choice of optimal retention time.

• Journal of Korean Society of Water and Wastewater
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• v.19 no.3
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• pp.357-362
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• 2005

Poly-${\gamma}$-glutamic acid (${\gamma}-PGA$), which is extracted from fermented soybeans, is a high molecular weight, adhesive, and negatively charged(anionic) polymer. Recently, ${\gamma}-PGA$ has gained attention due to its potential as polymer. The objectives of this study were to examine the applicability of ${\gamma}-PGA$ as a coagulant and/or a coagulant aid, to evaluate the efficiency of ${\gamma}-PGA$ for the removal of Organic and Ammonium substance in wastewater treatment. The effect of coagulation was evaluated for the removal of SS and organic matter using poly aluminum chloride(PACI) as well as newly developed ${\gamma}-PGA$. The maximum COD removal rate of 63% and the SS of 78% were occurred at the dosage of 50mg/L ${\gamma}-PGA$ only. The most effective removal for particulate and organic matter was occured when both PACI and ${\gamma}-PGA$ were applied at the rate of 20:1(10mg/L PACI and 0.5mg/L ${\gamma}-PGA$). When mixed with PACI, only small portion of ${\gamma}-PGA$ was enough to improve removal efficiencies of organic and particulate matter in wastewater. This result showed the positive potential of ${\gamma}-PGA$ as a new coagulant materials for wastewater treatment.

• Journal of Environmental Health Sciences
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• v.27 no.3
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• pp.43-48
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• 2001

Terephthalic acid and ethylene glycol resulting form the weight-reduction process of polyester make trouble in the operation of activated sludge process. Also, polyester weight loss wastewater shows high pH, high organic strength and wide variation of organic loading. Therefore, this study was conducted in order to improve treatment efficiency by activated sludge process with Pseudomonas sp degrading components of polyester weight loss wastewater. The CO $D_{Mn}$ and BO $S_{5}$ of the waste wastewater were 560~3,000 mg/$\ell$ and 8000~3,000 mg/$\ell$, respectively. pH was 11.8~12.3. COD removal efficiency by activated sludge-coagulation process with Pseudomonas sp was 94.1~95.8% for 35 hr of hydraulic retention time. Total organic carbon removal efficiency was 97.1%. Ethylene glycol and terephthalic acid in the wastewater were completely degraded during 32 hr of hydraulic retention time.e.

• Journal of the Korea Organic Resources Recycling Association
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• v.20 no.3
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• pp.52-59
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• 2012

As the result of reviewing the linked treatment of water quality for treating process at public livestock wastewater treatment facilities for fair selection of the proper linked process in case of linking sewage treatment plant for livestock wastewater, in case of wastewater processed by bio-reactor that is only biologically-treated, the load factor showed relatively high as 1.67%(base on design quality), 2.59%(base on operation quality) regarding COD and 3.69%(base on design quality), 7.67%(base on operation quality) regarding $COD_{Mn}$ but it is judged that there is nearly no influence on the operation of sewage treatment plan. And, in case of oxidized flotation-treated water & biofiltlation-treated water that are the advanced wastewater treatment, the load factor is approximately 1% and there is concern about the installation of excessive facilities in case of installing the advanced wastewater treatment. So, in case of considering the economic efficiency & stable operation of sewage treatment plant S, it is judged to be desirable to link with wastewater processed by bio-reactor that is biologically-treated.