• Journal of environmental and Sanitary engineering
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• v.10 no.1
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• pp.98-105
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• 1995

In the treatment of wastewater or sewage plant sludge with high solid concentration, high rate digestion process in which heating and mixing occur at a time is mainly used, and in the case of wastewater containing solid matter below 1000mg/ℓ the recently developed AF or UASB is developed Recently and commonly utilized. But these processes have weakpoints such as clogging of packing media and need of long period of trial run after microorganism granulation. In this point of view, there are active researches on the ASBR( anaerobic sequence batch reaction ) that is capable of treating of organic matter with reactor that has no packing materials and controlling the inflow time, reaction time sedimentation time and outflow time by time control without loss of microorganisms. The objectives of this study are to evaluate the efficiency of ASBR process according to the reaction time, change of treated water quality and gas output rate in the treatment of wheat plant wastewater.

• Journal of Korean Society on Water Environment
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• v.26 no.6
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• pp.969-975
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• 2010

Estimating the organic matter loadings from individual treated sewage has become important for establishment of effective management strategies to control refractory organic matter (R-OM) in watersheds. For this study, regression equations were constructed using treated sewage data to convert the chemical oxygen demand (COD) concentrations, which are mostly available from open database, into total organic carbon (TOC) and R-OM concentrations. Effluent samples were collected from five major sewage treatment plants (STPs) located upstream of the lake Paldang. Variations in the OM concentrations were not associated with either the location of the STP or the sampling season. The effluent investigated were characterized by higher ratio of R-OM with respect to biodegradable organic matter (B-OM) and higher presence of dissolved organic matters (DOM) versus particulate organic matter (POM). Compared to $COD_{Mn}$, $COD_{Cr}$ exhibited higher oxidation efficiencies and greater variations in the concentrations. The concentrations of $COD_{Mn}$ were positively correlated with dissolved organic carbon (DOC), total organic carbon (TOC), and R-OM concentrations. There was nearly no seasonal and annual variation in the regression equations between $COD_{Mn}$ and TOC or R-OM concentrations. The constructed regression equations for TOC and R-OM were $0.650({\pm}0.071){\times}COD_{Mn}+1.426({\pm}0.575)$ and $0.340({\pm}0.083){\times}COD_{Mn}+2.054({\pm}0.670)$, respectively. The established equations are expected to contribute to estimating OM loadings from the STPs into the lake Paldang and also to compensating for the deficiency of the data for effluent OM concentrations in STP.

• Journal of Korean Society of Water and Wastewater
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• v.23 no.6
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• pp.727-733
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• 2009

This study was performed to investigate the physical characteristics like compressive strength, permeability, porosity and the water quality removal characteristics of permeable concrete pavement filled with microbial-soil sheet to remove SS, organic matter and nutrients in artificial rainfall. As a result, it can show the removal efficiency is SS 90~95%, COD 85~93%, BOD 80~83%, T-N 61~75%, T-P 71~78% on WAPS I(W1) and WAPS II(W2). Therefore, permeable concrete pavement filled with microbial-soil sheet shows higher removal efficiency(SS 10%, organic matter and nutrients 30%) than a conventional porous concrete(W3). By filling microbial-soil sheet to permeable concrete pavement, we confirm that the function and efficiency are improved significantly and that a naturally-friendly facility can be developed and applied to treat non-point sources.

• Journal of Korean Society of Water and Wastewater
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• v.21 no.3
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• pp.323-329
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• 2007

There is no certain definition about advanced drinking water treatment but it is generally known as activated carbon process, membrane process or ozone process which can remove non-conventional pollutants such as taste and odor compounds, and micro-pollutants. There are more than 20 processes related to activated carbon as adsorber or biological activated carbon in Korea. The saturated carbon by pollutants can be reused by reactivation. However, the effect of reactivation on activated carbon is not well-understood in terms of changing physical properties of carbon to adsorption capacity of natural organic matter (NOM). In this study, the effects of reactivation on physical properties of activated carbon were investigated by isotherm and breakthrough of NOM. Ash content was increased from 8% to 13.3%. Iodine number is commonly used as an indicator for performance of reactivation. The iodine number was decreased about 20% after reactivating twice. The degree of reactivation can be evaluated by not only iodine number but also apparent density.

• Journal of Korean Society of Water and Wastewater
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• v.25 no.2
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• pp.249-255
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• 2011

It is complicate problem to optimize removing natural organic matter (NOM) by activated carbon in drinking water treatment because the activated carbon has heterogeneous surface area and pore structure. Seven different coals based activated carbons which have different pore structures were used in the study. Sand filtered effluents which normally used as GAC adsorber influent were used. The molecular weight distribution showed that most of the NOM was bigger than 10,000Da. In this study, systematical approaches such as characteristics of surface area and pore volume were evaluated on NOM adsorption. Especially, the adsorption capacities for NOM were evaluated by effect of micro-pores and meso-pores in surface area and pore structure. The results show that the higher ratio of meso-pore compare to the micro-pore has not only the better adsorption capacities for NOM but also the higher strongly-adsorbable fraction. Therefore, the overall adsorption capacity is increased with higher meso-pore ratio with existing of reasonable micro-pore surface area and volume.

• Journal of Korean Society of Water and Wastewater
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• v.23 no.4
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• pp.407-416
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• 2009

The objective of this study was to evaluate the variation of physical properties and adsorption capacity after regeneration of Granular Activated Carbon (GAC). It was found that the loss rate of regenerated carbon was related to the usage time of GAC. The correlations between iodide number and loss rate also determined. Effective size and uniformity coefficient for regenerated GAC were within a similar range compared to virgin GAC. This result indicated that the function as media is recovered. Although iodide number and specific surface area for regenerated GAC were not completely recovered compared to that of virgin GAC, cumulative pore volumes of regenerated GAC were increased. Removal efficiency of organic matter in regenerated GAC was resulted the same or slightly higher than that of virgin GAC. This result indicates that the number of mesopore responsible for removal of organic matter was increased after regeneration.

• Journal of Microbiology and Biotechnology
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• v.19 no.9
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• pp.1019-1027
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• 2009

A noncompartmented microbial fuel cell (NCMFC) composed of a Mn(IV)-carbon plate and a Fe(III)-carbon plate was used for electricity generation from organic wastewater without consumption of external energy. The Fe(III)-carbon plate, coated with a porous ceramic membrane and a semipermeable cellulose acetate film, was used as a cathode, which substituted for the catholyte and cathode. The Mn(IV)-carbon plate was used as an anode without a membrane or film coating. A solar cell connected to the NCMFC activated electricity generation and bacterial consumption of organic matter contained in the wastewater. More than 99% of the organic matter was biochemically oxidized during wastewater flow through the four NCMFC units. A predominant bacterium isolated from the anode surface in both the conventional and the solar cell-linked NCMFC was found to be more than 99% similar to a Mn(II)-oxidizing bacterium and Burkeholderia sp., based on 16S rDNA sequence analysis. The isolate reacted electrochemically with the Mn(IV)-modified anode and produced electricity in the NCMFC. After 90 days of incubation, a bacterial species that was enriched on the Mn(IV)-modified anode surface in all of the NCMFC units was found to be very similar to the initially isolated predominant species by comparing 16S rDNA sequences.

• Korean Journal of Ecology and Environment
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• v.38 no.spc
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• pp.62-66
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• 2005

The distributions of fluorescent whitening agents (FWA) in the water of the Yasu River and their tributaries flowing into Lake Biwa (Japan) were surveyed on winter and summer. The FWA fluxes had linear correlation with the corrected resident population in catchments of the tributaries of Yasu River. Therefore, the FWAs in the rivers come from domestic wastewater, and those fluxes in the tributaries depended on the human population of their catchments. As an application of the FWA indicating domestic wastewater, we could assess seasonal changes in the sources of dissolved organic matter in the tributaries.

• 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 Korean Society on Water Environment
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• v.25 no.4
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• pp.560-567
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• 2009

Treated or untreated wastewater may be a major source of refractory organic matters (R-OM) in drinking water sources. For this study, spectroscopic characteristics of wastewater OM were investigated using the samples from 20 wastewater treatment plants, which are located at the upstream of the lake Paldang, to suggest a estimate index for R-OM in wastewater. R-OM was quantified by measuring total organic carbon (TOC) concentration of the wastewater samples remaining after 28-day dark incubation. Among the traditional OM indices such as chemical oxygen demand (COD) and initial TOC, CODMn showed the lowest correlation coefficients with R-TOC of the samples. The ratios of carbonaceous biochemical oxygen demand (CBOD) to $COD_{Cr}$ had a better correlation with the percent distribution of R-OM than $BOD/COD_{Cr}$ ratios. terrestrial humic-like fluorescence (THLF) exhibited the highest correlation coefficient with R-TOC among the indices obtained from the synchronous fluorescence spectra of the samples. Milori index, one of the humification indices, showed a good correlation with the percent distribution of wastewater. This study demonstrated that fluorescence properties might be a better indices to estimate the concentrations and the distributions of wastewater OM compared to the specific UV absorbance (SUVA) values. Some useful formulas based on OM spectroscopic characteristics were finally suggested to predict R-OM in wastewater.