• 대한환경공학회지
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• 제22권6호
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• pp.1083-1091
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• 2000

본 연구는 펜톤산화 공정에서 발생되는 펜톤슬러지를 응집제와 펜톤산화 공정에서의 촉매로 재이용할 수 있는지 여부를 검토하여 고농도의 난분해성 유기물질을 함유한 침출수를 효과적이고 경제적으로 처리할 수 있는 기술을 개발하는데 그 목적을 두었다. Batch-Scale 연구 결과 펜톤슬러지를 응집제와 펜톤산화 공정의 촉매제로 혼합사용하여 응집 공정과 펜톤산화 공정에 적용할 경우 약품만을 사용하는 경우보다 응집제의 사용량을 50%, 펜톤산화 공정의 촉매제 사용량을 50% 감소시킬 수 있었으며, 응집 공정과 펜톤산화 공정에서 발생되는 슬러지의 발생량도 감소시킬 수 있는 것으로 조사되었다. 실험실 규모의 연속식 처리 실험을 수행한 결과 펜톤슬러지를 응집제로 재이용함으로써 평균 8.5% 정도 유기물 제거효율이 증가하였으며, 슬러지의 발생량은 35% 감소하는 것으로 조사되었다. 또한 펜톤슬러지를 펜통촉매제로 재이용함으로써 유기물 제거면에서 평균 5.3% 정도 효율이 증가하였으며, 슬러지의 발생량은 14% 정도 감소하는 것으로 조사되었다. 이상의 결과로 펜톤산화 공정에서 발생하는 슬러지의 재이용은 약품 비용이나 슬러지 처리 비용을 절감시킬수 있을 것으로 결론지을 수 있다.

• 한국환경과학회지
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• 제5권1호
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• pp.51-59
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• 1996

The purpose of this study was to evaluate the partial oxidation of the biological treatment plant effluents using Fenton's reagent as a pretreatment step prior to a tertiary biological oxidation of these effluents. Fenton's reagent was evaluated as a pretreatment process for inhibitory or refractory organics. Based on the Fenton oxidation system, the petrochemical wastewater treatment plant effluent was shown to have significant improvement in toxicity after oxidation with hydrogen peroxide. For example, at ranee of 42 ∼ 184 mg/L COD of petrochemical plant effluents, the COD removal efficiencies were from 38.2% to 60.1% after reaction with hydrogen peroxide 200 mg/L and Fe2+ 100 mg/L and reaction time was 30 minutes. The total TOC reduction were about 15.8∼22.4% with same test condition and difference between the overall removal rate and BOD/COD ratio after Fenton's oxidation estabilished in the biodegradation and otherwise meets the discharge standard or reuse for cooling tower make-up water.

• 청정기술
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• 제5권1호
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• pp.49-61
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• 1999

펜턴산화는 산화력이 매우 우수한 $OH{\cdot}$을 생성하여, 난분해성 유기폐수의 생분해성을 향상시킬 수 있으므로 다양한 용존 유기오염물질을 함유하고 있는 산업폐수의 처리에 널리 이용되고 있지만, 철염과 과산화수소 등의 약품비용과 Sludge 처분비용 때문에 현재로서는 그리 경제적인 공정이라고 볼 수 없다. 본 연구에서는 펜턴산화의 약품비용을 줄이고, 적은 약품으로 처리효율을 향상시키기 위한 변형 펜턴산화법과 혼합한 슬러지 재이용의 가능성을 제시하고자 하였다. 본 연구는 펜턴산화에서 사용되는 철염용액에 NaOH용액을 첨가하였더니 철염용액의 폭발적인 반응을 보고 이를 펜턴산화에 응용하게 되었다. 본 연구에서 제안하는 변형 펜턴산화 공정이란 펜턴산화에서 사용되는 철염용액에 NaOH를 넣어 적정 pH로 조정하여, 수산화물을 형성시킨 후 처리대상 시료에 주입하여 과산화수소와 반응시켜 $OH{\cdot}$을 형성시키는 방법이다. 이 때 대상시료로서는 대표적인 오염물질인 페놀을 사용하였고 자연수의 이온강도와 유사한 수준으로 맞추기 위하여 $NaHCO_3$를 적량 첨가하여 페놀 인공폐수를 조제하였다. 이를 이용하여, DO의 영향, 이온강도의 영향, 과산화수소 주입횟수에 따른 영향을 알아보았다. 또한, 침출수와 염색폐수에 적용시켜 본 결과 기존의 펜턴산화보다 더 나은 처리효율을 얻을 수 있었으며, 변형 펜턴산화법과 슬러지 반송을 조합하여 실험한 결과 철염을 50%만 주입하여도 기존의 펜턴산화와 유사한 수준의 처리효율을 얻을 수 있었다.

• 한국지구물리탐사학회:학술대회논문집
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• 한국지구물리탐사학회 2003년도 Proceedings of the international symposium on the fusion technology
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• pp.493-500
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• 2003

The effect of reductive treatment with elemental iron on the extent of mineralization by Fenton oxidation was studied for the explosive 2,4,6-trinitrotoluene (TNT) and hexahydro-l,3,5-trinitro-l,3,5-triazine (RDX) using a completely-stirred tank reactor (CSTR). The results support the hypothesis that TNT and RDX are reduced with elemental iron to products that are oxidized more rapidly and completely by Fenton's reagent. Iron pretreatment enhanced the extent of TOC removal by approximately $20\%\;and\;60\%$ for TNT and RDX, respectively. Complete TOC removal was achieved for TNT and RDX solutions with iron pretreatment under optimal conditions. On the other hand, without iron pretreatment, complete mineralization of TNT and RDX solutions were not achieved even with much higher $H_2O_2$ and $Fe^{2+}$ concentrations. The bench-scale iron treatment-Fenton oxidation integrated system showed more than $95\%$ TOC removal for TNT and RDX solutions under optimal conditions. The proposed zero-valent iron-Fenton process was evaluated with pink water from the Iowa Army ammunition plant. Results from batch and column experiments show that TNT, RDX, and octahydro-l,3,5,7-tetranitro-l,3,5,7-tetrazocine (HMX) were completely removed from the pink water and that triaminotoluene (TAT) and ${NH_4}^+$ were recovered as products in reduction with zero-valent iron. By using an integrated system, $83.3\pm4.2\%$ of TOC was removed in a CSTR with 10 mM of $Fe^{2+}$ and 50 mM of $H_2O_2$. These results suggest that the reduction products of TNT and RDX are more rapidly and completely mineralized by Fenton oxidation and that a sequential iron treatment-Fenton oxidation process may be a viable technology for pink water treatment.

• 한국지하수토양환경학회지:지하수토양환경
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• 제12권2호
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• pp.27-36
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• 2007

기존의 연구를 통해 Fenton's reagent(FR)를 이용하여 MTBE의 제거가 가능하며, 그러나 중성 pH영역에서는 철이온이 수산화물로 침전되어 반응성이 낮아지므로 FR만을 이용한 처리는 높은 수소이온 농도조건(pH $3{\sim}4$)이라는 제약으로 인해 직접적인 토양 및 지하수의 MTBE 오염처리에 있어 여러 가지 어려움이 있다. 이에 본 연구에서는 효과적인 처리를 위하여 NTA, oxalate, acetate 등의 chelating agent가 철이온과 반응하여 생성된 착화합물을 이용하는 modified Fenton reaction을 도입하여 중성 pH영역에서도 철이온이 안정화되어 높은 분해효율을 나타낼 수 있도록 하였다. MTBE의 분해경향은 chelating agent의 종류와 농도, 철이온 농도 그리고 pH 변화에 따라 크게 영향을 받는 것으로 나타났다. 가장 적합한 착화합물을 선택하기 위하여 총 6개의 chelating agent(citrate, oxalate, succinate, acetate, NTA, EDTA)를 실험한 결과, 처리효율과 chelating agent의 생분해도, 독성 등을 고려하여 최종 3가지 종(oxalate, acetate, NTA)이 선정되어 이후의 실험에서는 위의 3종만을 chelating agent로 이용하였다. 동일한 실험조건($H_2O_2$ : 5%, chelating agent : 6 mM, $Fe^{3+}$ : 2 mM, pH 7)하에서의 적용성 평가한 결과, Fe-NTA가 반응시작 30분만에 99.9%의 가장 높은 제거효율을 나타내었다. Oxalate의 경우, NTA보다는 그 분해효율이 낮으나 다른 chelating agent보다 상대적으로 높은 효율(24시간 후 최대효율 : 91.3%)을 보여주며, acetate를 이용한 경우도 본 실험에서 좋은 결과(24시간 후 최대효율 : 75.8%)를 나타내었다. 또한, 적정 철이온의 농도는 oxalate가 chelating agent로 이용되면 철이온 농도가 3 mM일때 가장 큰 분해효율을 보이며, acetate의 경우는 5 mM까지 농도가 증가함에 따라 그 효율도 조금씩 증가하는 것으로 나타났다. 이와같이 MTBE의 in-situ remediation을 위한 modified Fenton 공정은 철이온을 중성 pH영역에서 안정화시켜 실제 토양에 적용하였을 때, 높은 분해효율을 얻을 수 있으며, 경제적인 자체 생분해도가 높은 저분자 유기산을 이용하였으므로 생물학적 처리와 연계를 가능하게 해주는 장점을 나타낸다. 또한 토양 내 존재하는 철광석을 촉매로 이용할 경우, 주입되는 철이온 없이도 $H_2O_2$에서의 hydroxyl radical 생성을 증가 시킬 수 있으므로 보다 경제적이고 친환경적인 처리기법을 도출해 낼 수 있다.

• 한국환경과학회지
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• 제4권5호
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• pp.115-115
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• 1995

Reuse of industrial effluents through the cooling systems in a petrochemical complex was described. The partial oxidation of the effluents from the biological treatment plant was examined, using Fenton''s reagent as a pretreatment step prior to a next treatment of the effluents. Next tertiary treatment using fixed-film reactor resulted in marked reductions in COD and suspended solids. The continuous fixed-film process with Fenton oxidation pretreatment showed a 23% increase in the COD removal efficiency when compared to that without pretreatment of Fenton oxidation under the volumetric organic loading rate of 0.1 kg COD/m3/day. The Fenton oxidation treatment seemed to be a possible method for tertiary biological treatment to reduce the residual toxicity with the enhanced biodegradation of the effluents.

• Advances in environmental research
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• 제5권3호
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• pp.189-200
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• 2016

This study aimed at advanced oxidation of hetero tri-functional reactive dye Acid orange 7 using photo-Fenton conditions in a lab-scale experiment. Decolourisation of Acid Orange 7 dye by Fenton's process was dependent on concentration of Hydrogen peroxide, Ferrous sulphate, pH, and contact time. A $2^3$ factorial design was used to evaluate the effects of these key factors: pH, Fe(II), and $H_2O_2$ concentration, for a dye concentration of 50 mg/L with COD of 340 mg/L at pH 3.0. The response function was removal of colour under optimised conditions; pH 3.0, [Fe(II)] 40.83 mg/L, [$H_2O_2$] 4.97 mmol/L; 13.6 min. of treatment resulting in 100% colour removal. The final COD of treated wastewater was nil suggesting that AOP is a potentially useful process of color removal and dye degradation/mineralisation of effluent having AO7. Minimum contact time for complete decolourisation was at 5 mmol/l $H_2O_2$ concentration. Increase in $FeSO_4$ (mg/l) concentration resulted in decrease of time for complete decolourisation. Box-Behnken Design was used to optimize the process variables. Maximum and minimum levels of pH (3-5), $H_2O_2$ (4-6 mmol/l), $FeSO_4$ (30-46 mg/l) and contact time (5-15 minutes) were used. The statistical analysis revealed a value of 0.88 for coefficient of regression ($R^2$) indicating a good fit of model. Calculated F-value was found higher than the tabulated value confirming to significance of the model. Based on student's t-test, Ferrous sulphate, pH, and contact time have a positive effect on the percent decolourisation of Acid Orange 7.

• 한국환경과학회지
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• 제4권5호
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• pp.501-508
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• 1995

Reuse of industrial effluents through the cooling systems in a petrochemical complex was described. The partial oxidation of the effluents from the biological treatment plant was examined, using Fenton's reagent as a pretreatment step prior to a next treatment of the effluents. Next tertiary treatment using fixed-film reactor resulted in marked reductions in COD and suspended solids. The continuous fixed-film process with Fenton oxidation pretreatment showed a 23% increase in the COD removal efficiency when compared to that without pretreatment of Fenton oxidation under the volumetric organic loading rate of 0.1 kg COD/m3/day. The Fenton oxidation treatment seemed to be a possible method for tertiary biological treatment to reduce the residual toxicity with the enhanced biodegradation of the effluents.

• 한국환경과학회지
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• 제14권7호
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• pp.683-689
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• 2005

The consecutive combination process of a biological process as the pre-treatment and a chemical process as the post-treatment is applied for the dyeing wastewater. The poor efficiency of biological treatment using pure oxygen makes the chemical treatment cost high. It is necessary to improve the efficiency of biological treatment in order to reduce the cost of chemical treatment. The purpose of this paper is to find the minimum dose of chemical reagent to fit the Discharged Water Quality Standards for the different biological treatment effluents. Results revealed that the minimum dosage of Fenton's reagent lead to save the cost of chemical treatment based on the guideline dose in the treatment plant. The possible maximum saving reagents was up to $70\%$ for the effluent of the pilot plant packed with the carrier imbedded microorganisms which were selected from the present treatment plant.

• 한국환경보건학회지
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• 제28권1호
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• pp.51-65
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• 2002

This study was carried out to apply some basic physical and chemical treatment options including Fenton's oxidation, and to evaluate the performances and the characteristics of organic and nitrogen removal using lab-scale biological treatment system such as complete-mixing activated sludge and sequencing batch reactor(SBR) processes for the treatment of leachate from a municipal waste landfill in Gyeongnam province. The results were as follows: Chemical coagulation experiments using aluminium sulfate, ferrous sulfate and ferric chloride resulted in leachate CO $D_{Cr}$ removal of 32%, 23% and 21 % with optimum reaction dose ranges of 10,000～15,000 mg/$\ell$, 1,000 mg/$\ell$ and 500～2,000 mg/$\ell$, respectively. Fenton's oxidation required the optimum conditions including pH 3.5, 6 hours of reaction time, and hydrogen peroxide and ferrous sulfate concentrations of 2,000 ～ 3,000 mg/$\ell$ each with 1:1 weight ratio to remove more than 50% of COD in the leachate containing CO $D_{Cr}$ between 2,000 ～ 3,000 mg/$\ell$. Air-stripping achieved to remove more than 97% of N $H_3$-N in the leachate in spite of requiring high cost of chemicals and extensive stripping time, and, however, zeolite treatment removing 94% of N $H_3$-N showed high selectivity to N $H^{+}$ ion and much faster removal rate than air-stripping. The result from lab-scale experiment using a complete-mixing activated sludge process showed that biological treatability tended to increase more or less as HRT increased or F/M ratio decreased, and, however, COD removal efficiency was very poor by showing only 36% at HRT of 29 days. While COD removal was achieved more during Fenton's oxidation as compared to alum treatment for the landfill leachate, the ratio of BOD/COD after Fenton's oxidation considerably increased, and the consecutive activated sludge process significantly reduced organic strength to remove 50% of CO $D_{Cr}$ and 95% of BO $D_{5}$ . The SBR process was generally more capable of removing organics and nitrogen in the leachate than complete-mixing activated sludge process to achieve 74% removal of influent CO $D_{Cr}$ , 98% of BO $D_{5}$ and especially 99% of N $H_3$-N. However, organic removal rates of the SBR processes pre-treated with air-stripping and with zeolite were not much different with those without pre-treatment, and the SBR process treated with powdered activated carbon showed a little higher rate of CO $D_{Cr}$ removal than the process without any treatment. In conclusion, the biological treatment process using SBR proved to be the most applicable for the treatment of organic contents and nitrogen simultaneously and effectively in the landfill leachate.e.