• Journal of Environmental Policy
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• v.10 no.4
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• pp.61-80
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• 2011

Through concentrated investments in environmental regulations centered around BOD, which is a biodegradable matter index, and basic environmental infrastructures, national BOD pollution level has continuously improved. Nonetheless, limitations of BOD management system has become evident through nation-wide stagnation and/or increases of refractory organic matters, such as COD, at main drinking water sources, and the need for a new index, which can easily indicate different environmental conditions, has increased. Therefore, this study suggests a new organic management index for a proper management of surface water. $COD_{Cr}$ and TOC were examined as candidates for surface water quality management index, and it was found that TOC was more appropriate than $COD_{Cr}$ as an organic matter management index. Through this study, it was found that TOC possesses following qualities: a more representative index; international acceptability; monitoring program is easier; better availability of analysis techniques; better accuracy and precision of analysis; less time required for analysis; ease of operation; management of disinfection byproducts; connection with present policies; existence of foreign and domestic application case studies; and correlation with water ecosystem.

• Journal of Soil and Groundwater Environment
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• v.7 no.2
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• pp.13-22
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• 2002

Soil washing by surfactants is a technology to enhance mobilization and subsequent degradation of oil pollutants by reducing the surface tension of pollutants which is combined with soil. In this study, biosurfactant, rhamnolipid was produced from Pseudomonas aemginosa ATCC 9027 which had an excellent biodegradable activity in soil without causing secondary pollution. Effects of chemical surfactants on the removal of diesel from diesel-contaminated soil were compared to those of biosurfactants including rhamnolipid. Diesel removal efficiency by rhamnolipid extracted from P. aeruginosa culture broth was over 95% in both batch and column washing test in 5,000ppm diesel-contaminated soil with 1% surfactants after washing for 24 hours. On the contrary, the results of chemical surfactants were below 50∼80%, The chemical surfactants with HLB value(8∼15) showed more then 75% efficiency of diesel removal. But, when the HLB values were below 8 or over 15. their efficiency were observed as less then 60% of diesel removal. Rhamnolipid, biologically produced surfactants, may also be promising agent for enhancing diesel removal from contaminated soil.

• Journal of Korean Society of Environmental Engineers
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• v.37 no.7
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• pp.387-395
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• 2015

Anaerobic mesophilic batch test of several organic wastes were carried out by a graphical statistic analysis (GSA) to evaluate their ultimate biodegradability and two distinctive decay rates ($k_1$ and $k_2$) with their corresponding degradable substrate fractions ($S_1$ and $S_2$). Each 3 L batch reactor was operated for more than 100 days at the substrate to inoculum ratio (S/I) of 0.5 as an initial total volatile solids (TVS) mass basis. Their Ultimate biodegradabilities were obtained respectively as follow; 69% swine waste, 45% dairy cow manure, 66% slaughterhouse waste, 79% food waste, 87% food waste leachate, 68% primary sludge and 39% waste activated sludge. The readily biodegradable fraction of 89% ($S_1$) of Swine Waste BVS ($S_o$) degraded with in the initial 31 days with $k_1$ of $0.116day^{-1}$, where as the rest 11% slowly biodegradable fraction ($S_2$) of BVS degraded for more than 100 days with the long term batch reaction rates ($k_2$) of $0.004day^{-1}$. For the Food Waste and Waste Activated Sludge, their readily biodegradable portions ($S_1$) appeared 89% and 80%, which degrades with $k_1$ of $0.195day^{-1}$ and $0.054day^{-1}$ for an initial 15 days and 28 days, respectively. Their corresponding long term batch reaction rates ($k_2$) were $0.003day^{-1}$ and $0.002day^{-1}$. Results from other organic wastes are addressed in this paper. The theoretical hydraulic retention times (HRTs) of anaerobic digesters treating organic wastes are easily determined by the analysis of multiple decay rate coefficients ($k_1$ and $k_2$) and their corresponding biodegradable substrate fractions ($S_1$ and $S_2$).

• Journal of Korean Society of Environmental Engineers
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• v.22 no.2
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• pp.193-201
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• 2000

Partitioning of hydrophobic organic compounds (HOCs) to a biosurfactant, hydroxypropyl-${\beta}$-cyclodextrin (HPCD), was conducted to evaluate the feasibility of using HPCD to remove HOCs from soil/groundwater. HOC partitioning to HPCD was very fast, with over 95% of the complexation occurring within 10 min. Some influence of solution chemistry and HOC concentration on HOC-HPCD complex formation coefficients was observed. HPCD sorption on soil as quantified by both a fluorescence technique and total organic carbon measurements was negligible, indicating no significant affinity of HPCD for the solid phase. Although the HOC solubilization capability of HPCD was lower than that of synthetic surfactants such as SDS and Tween 80, HPCD can be effective in removing sorbed HOCs from a model subsurface environment, primarily because of its negligible sorption to the solid phase (i.e., all the HPCD added facilitates HOC elution). However, in contrast with conventional surfactants, HPCD becomes relatively less effective for HOC partitioning with increasing HOC size and hydrophobicity. Therefore, comparisons between HPCD and synthetic surfactants for enhanced remediation applications must consider the specific HOC(s) present and the potential for surfactant material losses to the solid phase, as well as other more generally recognized considerations such as material costs and potential toxicological effects.

• Journal of the Korean GEO-environmental Society
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• v.1 no.1
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• pp.79-85
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• 2000

The environmental assessment on the open dumping landfill of small scale which was situated in local small city was carried out to reuse the landfill site as the residental, commercial and other purposes through the analysis of the leachate of landfill, extracted solution from landfill waste. The waste was landfilled at 5.5~8m depth and the covered layer so poor as 20~50cm thickness. The biodegradable organic matters were almost degraded and the result of the leachate of landfill showed that the BOD/COD ratio were measured as 0.079, pH 7.2~7.6, SS 47736mg/L, COD 6193.8mg/L, T-N 596mg/L, and T-P 123.9mg/L respectively. These results were higher than those of extracted solution of landfill waste as the COD and BOD were measured as low values and T-N 7.77mg/L and T-P as 0.20mg/L lower concentrations the landfill appears the maturation phase. As the result of the assessment on the open dumping landfill of small scale, if appears that this landfill is maturation phase and the formation leachate is reduced. If the treatment facility of leachate from landfill and the layer which protects the inflow/infiltration is prepared, it can be safely used as this landfill site.

• Journal of Korean Society of Water and Wastewater
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• v.32 no.2
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• pp.159-168
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• 2018

Climate change is believed to increase the amount of dissolved organic matter in surface water, as a result of the release of bulk organic matter, which make difficult to achieve a high quality of drinking water via conventional water treatment techniques. Therefore, the natural water treatment techniques, such as managed aquifer recharge (MAR), can be proposed as a alternative method to improve water quality greatly. Removal of bulk organic matter using managed aquifer recharge system is mainly achieved by biodegradation. Biodegradable dissolved organic carbon (BDOC) and assimilable organic carbon (AOC) can be used as water quality indicators for biological stability of drinking water. In this study, we compared the change of BDOC and AOC with respect to pretreatment methods (i.e., ozone or peroxone). The oxidative pretreatment can transform the recalcitrant organic matter into readily biodegradable one (i.e., BDOC and AOC). We also investigated the differences of organic matter characteristics between BDOC and AOC. We observed the decreases in dissolved organic carbon (DOC) and the tryptophan-like fluorescence intensities. Liquid chromatographic - organic carbon detection (LC-OCD) analysis also showed the reduction of the low molecular weight (LMW) fraction (15% removed, less than 500 Da), which is known to be easily biodegradable, and the biopolymers, high molecular weight fractions (66%). Therefore, BDOC consists of a broad range of organic matter characteristics with respect to molecular weight. In AOC, low molecular weight organic matter and biopolymers fraction was reduced by 11 and 6%, respectively. It confirmed that biodegradation by microorganisms as the main removal mechanism in AOC, while BDOC has biodegradation by microorganism as well as the sorption effects from the sand. $O_3$ and $O_3+H_2O_2$ were compared with respect to biological stability and dissolved organic matter characteristics. BDOC and AOC were determined to be about 1.9 times for $O_3$ and about 1.4 times for $O_3+H_2O_2$. It was confirmed that $O_3$ enhanced the biodegradability by increasing LMW dissolved organic matter.

• Journal of the Korea Organic Resources Recycling Association
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• v.12 no.4
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• pp.139-147
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• 2004

We have isolated two bacterial strains, FM-02 and AL-02, which produced EPS from forest soil for the restoration of forest fire by promoting soil aggregation. FM-02 was found to be Gram negative rod and belong to Beta Proteobacterium sp. through 16s-rDNA sequence analysis, and AL-02 was Gram positive rod and showed 81% of similarity to Zoogloea sp. through the analysis of 16s-rDNA sequence. FM-02 and AL-02 produced about 1.8g and 8.3g of EPS, respectively, per 1L of culture as dry weight. Flocculation activity (FA) was also measured in two strains. FM-02 showed 2.31 FA against active carbon, and AL-02 showed 6.21 FA against kaolin clay. From these results, we expect that AL-02 strain will be applied as a good biological material for the reduction of forest soil erosion by wild and rain after fire through promoting coagulation of soil particles.