• 한국물환경학회지
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• 제22권5호
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• pp.895-904
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• 2006

The improved MLE (modified Ludzack-Ettinger) process was operated for piggery waste treatment in full-scale public livestock waste treatment plant. The treated waste from bioreactor was suitable for the strict effluent standard of 200 mgCOD/L and 60 mgTN/L as it was dewatered chemically without settling tank and passed through filtration process. Though this treatment method produced a great deal of sludge ($6.4m^3\;per\;m^3$ dewatered piggery waste) it was able to accomplish predominant effluent quality by removing non-biodegradable COD and color without advanced oxidation process as ozone, fenton and etc.. The nitrogen removal efficiency of bioreactor was rapidly declined from March to May (from 0.016 to 0.005 kgN/kgVSS-day) when disinfection is in earnest as well as from warm season when reactor temperature rises higher than $35^{\circ}C$(from 0.016 to 0.008 kgN/kgVSS-day). This study proves that counterplanes for infection residuals, bioreactor temperature and dewatering sludge reduction are necessary for piggery waste treatment.

• 한국물환경학회지
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• 제22권1호
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• pp.51-58
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• 2006

The effluent limitations for individual industry based on the best available technology economically achievable (BAT) have been required to achieve effective regulation. BAT assessment criteria that are suitable for the circumstances of Korean industry were developed in the previous study. The criteria were applied to determine the BAT for leather tanning and finishing industry. For the evaluation BAT, a subcategorization for the industry considering wastewater characteristics, source equipments, raw material and so on should be suggested. Three subcategories: A) Unharing, Chrome Tan, Retan-Wet Finish, B) Chrome Tan, Retan-Wet Finish, and C) Furskins were proposed in this study. Wastewater discharged from the each category contains high concentration of COD, chrome, nitrogen and sulfide. In particular, the concentration of nitrogen from the subcategory A is significantly greater. Twenty sites were surveyed and wastewater qualities were analyzed. Therefore, six different technologies were applied to the subcategory A for the end-of-pipe treatment technology, and a technology was used in the subcategory B and C, respectively. The technology candidates were evaluated in terms of environmental impacts, economically achievability, treatment performance and economical reasonability. As the result, the technology options for each subcategories: A) primary chemical precipitation + modified Ludzack-Ettinger process (MLE) + secondary chemical precipitation, B) chemical precipitation + typical activated-sludge process + Fenton oxidation, C) chemical precipitation + typical activated-sludge process + batch Fenton oxidation or batch activated carbon treatment were selected as the BAT, respectively.

• 펄프종이기술
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• 제40권5호
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• pp.53-59
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• 2008

This study was carried out to investigate the effect of photocatalysis using $TiO_2$ and UV applied for the COD reduction of wastewater in linerboard mill. Trials were done to obtain the optimum addition amounts of $TiO_2$ and $H_2O_2$ to the wastewater and find an appropriate pH condition for photocatalysis on $TiO_2$ for degrading COD. The photocatalytic reaction was applied to the wastewater collected after secondary activated sludge treatment in WWTP of linerboard mill. The optimum application of photocatalysis reaction was obtained under the addition conditions of 2 g/L of $TiO_2$ and 200 mg/L of $H_2O_2$ at pH 3.0, respectively. The removal efficiency of $SCOD_{Cr}$ by photocatalytic treatment was 86.4 % and higher than Fenton treatment in which removal efficiency was 67.4 %. It was concluded that the photocatalytic process using $TiO_2$ and UV could be applied to the wastewater treatment in linerboard mill and also to the dramatic drop-off in NBDCOD load from wastewater of tertiary treatment in WWTP.