GBGP 시스템에 기반한 다변량 동적 공정 모델을 이용한 KNR 생물학적 고도처리공정의 성능예측

백병천 한국도시환경학회 2022 한국도시환경학회지 Vol.22 No.3

Biological wastewater treatment systems are characterized by large temporal variability of inflow, variable concentrations of components in the incoming wastewater to the plant, and highly variable biological reactions within the process. This paper proposes an automatic process model induction system using an evolutionary computional intelligence, called grammar-based genetic programming (GBGP), that is specially designed to automatically discover multivariate dynamic process models that best fit observed process data. This automatic process model induction system combines an evolutionary self-organizing system of genetic programming paradigm with various mathematical functions for a multivariate nonlinear model evolution using a grammar system via the mechanism of genetics and natural selection. In the GBGP, a four-step modelling procedure was performed: (1) initialization: generatr an initial population of P models using contex-free grammar. generation K=0; (2) optimize each model (variables and constants) in the population; (3) execute and evaluate the fitness of each model in the population; (4) genetic loop: repeat until termination criterion is met (maximum generation Kmax). The results demonstrate that the multivariate dynamic process modelling technique presented using a grammar-based genetic programming (GBGP) provides a valuable tool for predicting the out puts with high levels of accuracy and identifying key operating variables for the full-scale KNR biological nutrient removal process. These modells are derived automatically in the form of understandable mathematical formulas that enable engineers to extract important knowledge hidden in the data and develop better operation and control strategies. 생물학적 폐수처리 시스템은 시간에 따른 유입 폐수량의 변화가 크고 , 처리장으로 유입되는 폐수내의 다양한 성분과 농도의 변화 가 클 뿐 만 아니라 , 처리공정 내에서 매우 가변적인 생물학적 반응을 나타내는 특징을 가진다 . 본 논문에서는 측정된 공정 데이터에 가장 적합한 다변량 동적 공정 모델이 자동으로 생성되도록 고안된 학습기반 유전자 프로그래밍 (GBGP)이라는 진화적 전산 지능을 사용한 자동 공정 모델 유도 시스템을 제안하였다 . 이 자동 공정 모델 유도 시스템은 유전자 프로그래밍의 진화적 자기구성 시스템 과 유전학 및 자연선택 메카니즘을 통해 학습 시스템을 사용하여 만들어진 다변형 비선형 모델 진화를 위한 다양한 수학적 기능과 결합되어 있다 . GBGP에서 4단계의 모델링 절차가 수행되었다 . (1) context-free grammar를 이용하여 P 모델의 초기 개체군 (세대 K=0)을 생성시키는 초기화 , (2) 변수와 상수의 각 모델에 대한 최적화 , (3) 각 모델에 대한 적합도 실행 및 평가 , (4) 세대 K=Kmax 가 될 때까지 반복 실행하는 유전자 루프 (genetic loop). 모델링 결과 학습기반 유전자 프로그래밍 (GBGP)으로 만들어지는 다변량 동 적 공정 모델링 기술이 실제 처리장 규모의 KNR 생물학적 고도처리 공정을 높은 정확도로 출력을 예측하고 주요 작동 변수를 식별 하는 데 유용한 도구임을 보여주었다 . 이 모델은 엔진니어가 데이터에 숨겨진 중요한 지식을 알아내고 더 나은 처리장 운영 및 제어 전략을 개발할 수 있도록 이해하기 쉬운 수학 공식의 형태로 자동적으로 생성된다 .

미량오염물질 제거능 향상을 위한 생물활성탄 공정의 강화

손희종,정은영,염훈식,최상기,박홍기 대한환경공학회 2023 대한환경공학회지 Vol.45 No.12

목적 : 본 연구에서는 생물막 특성이 강화된 BAC 공정에서의 미량오염물질의 제거효율을 일반 BAC 공정과 비교·평가하여, 정수장의 BAC 공정에서 미량오염물질의 제거효율을 상승시킬 수 있는 방안을 제시하고자 하였다. 방법 : 대상 미량오염물질로는 dibromo-methylparaben (Br2-MP)를 선정하였다. 회분식 실험과 실험실 규모 컬럼 실험을 수행하여 일반 BAC 공정과 인(P) 및 과산화수소(H2O2)를 첨가하여 생물막 특성을 강화한 BAC에서 Br2-MP의 제거 효율을 평가하였다. 회분식 및 실험실 규모의 컬럼 실험 결과를 사용하여 생분해 동역학을 평가하였다. 결과 및 토의 : 동일한 생체량 조건(2.0±0.2×107 cells)에서 Br2-MP의 제거효율을 비교한 회분식 실험에서 생물학적 활성도가 높게 나타난 강화 BAC 공정의 생물분해 속도상수(kbio)는 일반 BAC 공정보다 1.2배 높았다(강화 BAC: 3.4±0.3 mg·C/g·hr, 일반 BAC: 2.9±0.4 mg·C/g·hr). 동일한 습중량(1 g) 조건으로 Br2-MP의 제거효율을 비교한 회분식 실험에서, 생체량 함량이 높은 강화 BAC 공정의 생물분해 속도상수(kbio)는 일반 BAC 공정보다 1.9배 더 높았다(강화 BAC: 3.5±0.4 µg·ATP/g·GAC, 일반 BAC: 2.3±0.2 µg·ATP/g·GAC). 회분식 실험을 통해 강화 BAC 공정은 부착된 박테리아의 생체량과 활성이 증가하여 Br2-MP 제거에 더 효율적이었다. 다양한 수온(5, 25℃)과 공탑 체류시간(EBCT: 5-40분) 조건에서 실험실 규모의 컬럼 실험을 진행한 결과, 전체 운전 기간 동안 일반 BAC 공정에 비해 강화 BAC 공정에서 Br2-MP의 제거효율이 더 높은 것으로 나타났다. 특히, 저온(5℃)과 짧은 EBCT(5분)에서 강화 BAC 공정과 일반 BAC 공정의 Br2-MP 제거효율은 큰 차이를 나타내었다. 5℃와 25℃에서 일반 BAC 공정의kbio는 각각 0.0229 min-1, 0.0612 min-1, 강화 BAC 공정의 kbio는 각각 0.0470 min-1, 0.1421 min-1로 강화 BAC 공정이 일반 BAC 공정에 비해 2배 이상 빠른 Br2-MP 생분해능을 나타내었으며, 이러한 결과는 회분식 실험결과와도 유사하였다. 또한, 하절기 잦은 EBCT 변경에 대한 영향을 시뮬레이션한 실험에서 강화 BAC 공정은 일반 BAC 공정에 비해 상대적으로 안정적인 Br2-MP 제거효율을 유지하였다. 결론 : 강화된 BAC 공정은 일반 BAC 공정에 비해 우수한 미량오염물질 생물분해능을 나타내었다. 다만 경제성(인산염과 과산화수소 비용 등)과 수질을 고려할 때 하절기와 같이 EBCT가 단축되거나 수온이 낮아지는 동절기에 한하여 간헐적으로 강화 BAC 공정을 운영하는 것도 효율적인 대안으로 평가되었다. Objectives : In this study, the removal efficiency of micropollutants in the biological activated carbon (BAC) process was investigated, and a method for improving the removal efficiency of micropollutants in the BAC process of water treatment plants was proposed.Methods : Dibromo-methylparaben (Br₂-MP) was selected as the target micropollutant. Batch and lab-scale column experiments were conducted to evaluate the removal efficiencies of Br₂-MP in the conventional BAC process and the BAC with enhanced biofilm properties by the addition of phosphorus (P) and hydrogen peroxide (H₂O₂). Biodegradation kinetics were evaluated using results from batch and lab scale column experiments.Results and Discussion : As a result of comparing the removal efficiency of Br₂-MP in a batch experiment with the same biomass concentrations (2.0±0.2×10⁷ cells), the biodegradation rate constant (<i>k</i>_bio) of the enhanced BAC process was found to be 1.2 times higher than that of the conventional BAC process due to its higher biological activity (enhanced BAC: 3.4±0.3 mg·C/g·hr, conventional BAC: 2.9±0.4 mg·C/g·hr). Comparison of removal efficiencies of Br₂-MP in batch experiments with the same wet weight of BAC (1 g) showed that the biodegradation rate constant (<i>k</i>_bio) of the enhanced BAC process was 1.9 times higher than that of conventional BAC process due to higher biomass (enhanced BAC: 3.5±0.4 µg·ATP/g·GAC, conventional BAC: 2.3±0.2 µg·ATP/g·GAC). Through the batch experiments, the enhanced BAC process was efficient in removing Br₂-MP via increasing both biomass concentrations and activity of attached microorganisms. Lab-scale column experiments conducted under different water temperatures (5 and 25℃) and empty bed contact time (EBCT: 5-40 min) conditions showed higher removal efficiency of Br₂-MP in the enhanced BAC process than the conventional BAC process throughout the entire period of operation. In particular, the removal efficiency of Br₂-MP between the enhanced and conventional BAC processes showed significant differences at low temperature (5℃) and short EBCT (5 min). At 5℃ and 25℃, the kbio of the conventional BAC process was 0.0229 min^-1 and 0.0612 min^-1, respectively, and the <i>k</i>_bio of the enhanced BAC process was 0.0470 min^-1 and 0.1421 min^-1, respectively, These results showed that the enhanced BAC process had two times higher biodegradability of Br₂-MP than the conventional BAC process. These results showed a similar trend to the results from the batch experiment. In an experiments simulating the impact of frequent EBCT changes during summer, the enhanced BAC process maintained a relatively stable removal efficiency of Br₂-MP compared to the conventional BAC process.Conclusion : The enhanced BAC process showed superior biodegradation of micropollutant compared to the conventional BAC process. Considering economic costs (e.g., costs of adding phosphate and hydrogen peroxide) and water quality, it appears to be an efficient alternative to operate the enhanced BAC process intermittently, limited to cases where EBCT is shortened, such as summer, or when water temperature is low, such as in winter.

생활하,폐수의 합병처리를 위한 혼합폐수처리시스템의 구성 및 혼합 수질예측

최정우 ( Jeung Woo Choi ),현길수 ( Kil Soo Hyun ),송인수 ( In Soo Song ) 한국수처리학회 2003 한국수처리학회지 Vol.11 No.1

Using anaerobic-oxidation biofilm process(AOBP), rotating biological contactor(RBC), biological aerobic filtration (BAF), activated sludge(AS), and coagulation-sedimentation (C-S) processes as a pretreatment processes of the mixtured wastewater, this research were performed to investigate on the characteristics of the pretreatment processes and to predict the wastewater qualities mixed domestic wastewater with the mixtured wastewater of night soil and leachate, considered the reduction of organic loadings. Hydraulic retention time (HRT) of the pretreatment processes were in the range of 9 -10 hours for the AOBP, 10-12 hours for the RBC, 7-8 hours for the BAF, and 7-8 hours for the AS. The C-S experiment was carried out by Jar tester. As a results, the biofilm treatment processes(BTP) such as AOBP. RBC and BAF showed more effective 71-76% for COD, 42-64% for T-N, and 58-70% for T-P than AS and C-S, respectively. For the removal of heavy metal of Cr^(+6), the BTP as well as the C-S was extremely more effective about 50% than the AS. It indicated that the BTP was more stable and effective process as a pretreatment processes of the mixtured wastewater, compared to the AS and the C-S processes. Applied organic reduction rates of 30% and 60% by the RTP for the prediction of mixtured wastewater, the reduction efficiencies of it were 32% and 39% for COD, 10% and 15% for T-N, and 16% and 20% for T-P, respectively. Despite of the increase of two times in reducing organic loadings, the reduction efficiencies of 4∼7% resulted in an ineffective operation of the BTP.

낙동강 하류원수를 대상으로 모의 고도 정수처리공정을 이용한 N-Nitrosamine류 제거능 평가

김경아,손희종,서창동,염훈식,송미정,류동춘 대한환경공학회 2019 대한환경공학회지 Vol.41 No.1

In this study, 8 nitrosamines (N-nitrosodimethylamine (NDMA), N-nitrosomethylethylamine (NMEA), N-nitrosopyrrolidine (NPYR), N-nitrosodiethylamine (NDEA), N-nitrosopiperidine (NPIP), N-nitrosomorpholine (NMOR), N-nitrosodi-n-propylamine (NDPA), N-nitrosodi-n-butylamine (NDBA)) were spiked into rapid sand-filtration water and post-ozone treatment water and the removal efficiencies in post-ozone (O3), O3/hydrogen peroxide (H2O2), ultraviolet (UV), UV/H2O2 and biological activated carbon (BAC) processes were simulated on a laboratory scale. As a result of simulating the O3 and O3/H2O2 processes at the drinking water treatment plant (DWTP) with O3 input concentration of 2 mg/L for short chain-nitrosamines such as NDMA, NMEA and NDEA, the removal efficiency was as low as 40% or less. On the other hand, long chain-nitrosamines and aliphatic cyclic structures such as NDPA, NPYR, NMOR, NPIP and NDBA showed relatively high removal efficiencies of about 40% to 90%. The removal efficiencies of nitrosamines in UV alone and in UV/H2O2 processes were 59~96% (UV dosage: 500 mJ/cm2) and 86~100% (UV dosage: 1000 mJ/cm2), respectively. The removal efficiency of UV/H2O2 process was almost similar to that of UV alone process. In the BAC process, NDMA showed the highest removal efficiency among 8 nitrosamines. The removal efficiencies of NDMA were 71% and 94%, respectively, when water temp. were 10℃ and 25℃ and EBCT was 15 min. In the case of NMOR with the lowest removal efficiencies, the removal rates were 27% and 42%, respectively. The removal efficiencies in the BAC process were in the order of NDMA, NMEA, NDEA, NDPA, NDBA, NPYR, NPIP and NMOR. In order to effectively control of nitrosamines in large scale DWTPs located downstream of the Nakdong River, an advanced oxidation process based on UV is more suitable than the O3 and O3/H2O2 processes currently in operation. In the case of the O3 and O3/H2O2 processes, it was also evaluated that it is possible to efficiently control the nitrosamines introduced into the DWTP when operated in combination with BAC process. 본 연구에서는 급속모래 여과수와 후오존 처리수에 8종의 nitrosamines (N-nitrosodimethylamine (NDMA), N-nitrosomethylethylamine (NMEA), N-nitrosopyrrolidine (NPYR), N-nitrosodiethylamine (NDEA), N-nitrosopiperidine (NPIP), N-nitrosomorpholine (NMOR), N-nitrosodi-n-propylamine (NDPA), N-nitrosodi-n-butylamine (NDBA))를 투입하여 후오존, 후오존/과산화수소, 자외선, 자외선/과산화수소 및 생물활성탄 공정에서의 제거능을 실험실 규모의 실험장치로 모사하였다. NDMA, NMEA 및 NDEA와같은 단쇄 nitrosamine류들에 대해 오존 투입농도를 2 mg/L로 하여 정수장에서의 후오존 및 후오존/과산화수소 공정을 모사한 결과, 40% 이하의 낮은 제거율을 나타내었다. 반면 NDPA, NPYR, NMOR, NPIP 및 NDBA와 같은 장쇄 및 지방족 고리구조를 가지는 nitrosamine류들은 40~90% 정도의 비교적 높은 제거율을 나타내었다. 정수장의 후오존 공정을 대체할 목적으로자외선 단독공정과 자외선/과산화수소 공정에서의 nitrosamine류들에 대한 제거능을 모사한 결과, 자외선 단독공정에서 조사량 500 mJ/cm2과 1000 mJ/cm2일 때의 제거율이 각각 59~96% 및 86~100%로 나타났으며, 자외선/과산화수소 공정에서의 제거율은 UV 단독공정과 거의 유사하게 나타났다. 생물활성탄 공정에서의 nitrosamine류 8종의 제거능을 모사한 결과, 가장 높은제거율을 나타낸 물질은 NDMA였으며, 수온이 10℃와 25℃일 때 EBCT 15분에서의 제거율이 각각 71%와 94%였으며, 가장낮은 제거율을 나타낸 NMOR의 경우는 각각 27%와 42%의 제거율을 나타내었다. 생물활성탄 공정에서의 제거율은 NDMA, NMEA, NDEA, NDPA, NDBA, NPYR, NPIP, NMOR 순이었다. 낙동강 하류에 위치한 대규모 정수장에서 nitrosamine류의 효과적인 제어를 위해서는 현재 운영 중인 후오존 및 후오존/과산화수소 공정 보다는 자외선을 기반으로 하는 고도 산화공정이 적합하였으나 후오존 및 후오존/과산화수소 공정의 경우도 후단의 생물활성탄 공정과 조합하여 운영하면 정수장으로 유입된 nitrosamine류에 대해 효율적인 제어가 가능한 것으로 평가되었다.

전산화 공정에 의한 microcystin 용출 및 고도처리에 의한 제거 특성

염훈식,손희종,류지승,정은영,김경아 대한환경공학회 2019 대한환경공학회지 Vol.41 No.10

목적 : 하절기 고농도의 Microcystis sp. 함유 원수가 정수장으로 유입시에 전산화 공정에서의 microcystin (MCs) 용출과 후단의 고도 정수처리 공정에서 용출된 MCs의 제거 가능성 평가가 목적이다. 방법 : 고농도 Microcystis sp. 함유원수(400,000 cells/mL)를 이용하여 전염소와 전오존 처리에 의한 MCs 용출 특성을 평가하였으며, 후단의 고도 정수처리 공정인 O3, O3/H2O2, UV/H2O2 및 BAC 공정에서의 전산화 처리에 의해용출된 MCs 제거 특성을 평가하였다. 결과 및 토의 : 전염소 투입농도가 증가할수록 수중으로 용출된 MCs 농도는 급격히 증가하다가 염소 투입농도 5 mg/L 이상에서는 감소하였고, 용출된 MCs의 대부분은 MC-RR (57∼86%)과 MC–LR (11∼29%)이 차지하였다. 전염소 처리 이후 전오존 처리공정에서 오존 투입농도가 증가할수록 수중의 MCs 농도는 처리 전에 비해 수∼수십배 정도 증가하였으나, 전염소를 3 mg/L 이상으로 처리한 경우에는 오존 투입농도가 증가할수록 MCs가 급격히제거되었다. 전산화 처리 후, 응집-침전 처리수 중의 MCs 농도가 처리 전에 비하여 2배 이상 급격히 증가였으며, 침전공정 동안 산화제에 손상된 Microcystis 조체에서 MCs가 지속적으로 유출되었다. 후산화 공정에서는 O3과O3/H2O2 공정이 UV/H2O2 공정에 비해 MCs 제거에 효과적이었고, O3과 O3/H2O2 공정에서 1 mg/L 이상으로 O3을투입한 경우 MCs가 100% 제거되었다. BAC 공정에서는 MCs 유입농도가 각각 0.8 μg/L와 2.8 μg/L일 때 EBCT 15분에서 각각 100%와 93% 제거되었으며, MC-RR에 비해 MC-LR의 생물분해 제거능이 낮았다. 고농도의 MCs가유입되거나 MC–LR의 구성비율이 높을 경우에는 BAC 공정의 EBCT를 증가시켜 운전할 필요가 있었다. 결론 : 고농도 Microcystis sp. 함유 원수를 전산화 처리하면 고농도의 MCs이 용출되었으나 후단의 O3, O3/H2O2, UV/H2O2 및 BAC 공정과 같은 고도 정수처리 공정에서 제거가 가능하였다. 특히, UV-AOP 공정에 비해 O3 공정에의한 MCs 제거율이 높았으며, BAC 공정에서도 EBCT 15분의 조건에서는 93∼99%의 MCs가 제거되었다. Microcystis sp.가 번성하는 시기에 응집/침전 공정의 효율 증진을 위해 전산화 공정을 적용하는 정수장에서는 후단에 O3/BAC 공정을 적용할 경우 MCs 제거에 매우 효과적으로 나타났다. Objectives : The objectives of this study were to evaluate the characteristics of microcystins (MCs) release form Microcystis sp. in surface water during pre-oxidation process using chlorine and ozone and it’s removal by advanced water treatment process as post process when raw water containing high Microcystis sp. is introduced into the water treatment plant. Methods : Raw water which had contained over 400,000 cells/mL of Microcystis sp. were used to evaluate the characteristics of MCs released from Microcyctis sp. and chlorination (Cl2) and ozonation (O3) were used as pre-oxidation process and O3, O3/H2O2, UV/H2O2 and biological activated carbon (BAC) were used as post oxidation process. Results and Discussion : As the concentration of chlorine increased, the concentration of released MCs in the water increased, but decreased when higher than 5 mg/L of chlorine dosage. Released MCs were consisted of almost MC-RR (57∼86%) and MC–LR (11∼29%). In the ozone treatment after prechlorination process, the MCs concentration was increased by several fold to dozen fold to compare before ozonation. However, when chlorine dosage was over 3 mg/L, MCs were rapidly removed as the ozone concentration increased. The MCs concentration of flocculation/sedimentation treated sample after the pre-oxidation was increased more than two times before treatment, the MCs was continuously released during the coagulation/sedimentation process from the damaged Microcystis sp. due to the prior oxidation process. In the post-oxidation process, O3 and O3/H2O2 processes were more effective for removing MCs than the UV/H2O2 process, and O3 and O3/H2O2 processes removed 100% of the MCs when O3 was added above 1 mg/L. 100% and 93% were removed respectively at 15 minutes of EBCT (empty bed contact time) in the BAC process, when the MCs concentrations of influent were 0.8 μg/L and 2.8 μg/L. The biodegradability of MC-LR was lower than that of MC-RR. It was necessary to increase the EBCT of the BAC process when the concentrations of MCs or the ratio of MC-LR were high. Conclusions : Although, pre-oxidation treatment to the raw water containing high concentration of Microcystis release higher MCs concentration in the oxidized water, that can be removed by post O3, O3/H2O2, UV/H2O2 and BAC processes. The removal rate of MCs by O3 process was higher than that of UV-AOP process, and 93∼99% of MCs removed with 15 min of EBCT in BAC process. In the drinking water treatment plant where the pre-oxidation process is applied to improve the efficiency of the flocculation/sedimentation process during the blooming season of Microcystis sp., O3/BAC process after the flocculation/sedimentation process is recommendable to MCs remove.

하수처리공법의 잠재적 환경영향 분석을 위한 전과정 평가지수의기여도 평가

권순구,김영희 한국도시환경학회 2018 한국도시환경학회지 Vol.18 No.3

Pollutant removal efficiency and installation cost are important factors to consider wastewater treatment process. However, practically during its operation, the input sources such as chemical use, amount of electricity used, waste sludge and so on are different according to characteristic of wastewater treatment process. Furthemore negative environmental influence such as resource depletion, energy consumption, air contaminant when generating electric-power were not considered as assessment factor to select the treatment process. This study analyzed environmental impact of MAR and A2O process using LCA (Life Cycle Assessment) in order to estimate contribution of potential environmental effects between A2O process and MBR process of sewage plant in Korea. Each process was set as system boundary and LCIA (Life Cycle Impact Analysis) by inputs and outputs was carried on. Specialized extruded values were obtained with the results of LCIA. A2O process has slightly higher environment load then MBR process with EP (Eutrophicaiton Potential) value of 7.09E-03 (kg PO43-eq/kg) for the fomer and 7.26E-03 (kg PO43-eq/kg) for the later. This was understood as treatment efficiency of MBR process has more higher then A2O process. However, MBR process showed its GWP of 9.13E-01 (kg CO2 eq/kg) which is approximately 5 time larger than of A2O process showing 1.60E-01 (kg CO2 eq/kg). For an analysis based on each influence category, contribution rate of water pollutant process about both processes had over 95% on EP, however, it is showed that A2O process had 85%, MBR process had over 96% on electricity related to global warming on GWP. As the results represented, it is concluded to allow for electricity consumption and water pollutant based on treatment process are Key contributor on WWTP. Sewage treatment process has been evaluated by treatment efficiency, cost of maintenance, etc., however, negative environmental effect of global warming can be passing out easily if electricity is only concerned on maintenance cost of WWTP. That is understood as a way that leads sustainable improvement in the waste water treatment which is one of national base facility with evaluating process efficiency as well as environmental anlaysis on LCA. 하수처리장의 공법 적용시 수질오염물질의 처리효율과 시설 설치비용이 검토되어지고 있다. 하지만, 하수처리시설은각 공법의 특성에 따라 화학약품 투입량, 전력사용량, 폐슬러지 발생량 등 시설의 유지관리에 투입되고 배출되는 요소들이 다르며, 이는 곧 비용적인 측면과 자원고갈, 에너지 소모, 전력 생산시 발생할 수 있는 대기오염물질 유발 등과 같이부정적인 환경영향을 야기 할 수 있다. 이에 본 연구에서는 LCA기법을 활용하여 하수처리공법의 잠재적 환경영향에 미치는 기여도를 파악하고자 국내 하수종말처리시설 중 A2O공정과 MBR공정으로 운전되고 있는 하수처리장의 데이터를활용하여, 운전단계에 대한 전과정평가를 수행하였다. 각 공법의 투입물과 배출물에 따른 목록분석(Life Cycle Inventory Analysis, LCIA)을 통한 환경영향평가(Life Cycle Impact Assessment, LCIA)의 특성화결과 값을 도출하였다. 부영양화지수(Eutrophicaiton Potential, EP)는 MBR공정이 7.09E-03(kg PO43-eq/kg), A2O공정이 7.26E-03(kg PO43-eq/kg)으로A2O공정이 부영양화에 대한 환경부하가 더 많았으며, 이는 MBR공정의 하수처리 효율이 높기 때문으로 파악되었다. 지구온난화지수(Global Warming Potential, GWP)는 A2O공정이 1.60E-01(kg CO2 eq/kg), MBR공정이 9.13E-01(kg CO2 eq/kg)으로 MBR공정이 약 5배 이상 지구온난화에 미치는 영향이 더 많은 것으로 분석됐다. 각 영향범주에 미치는 단위공정을 분석한 결과 부영양화 범주는 하수처리장에서 처리 후 배출되는 수계오염물질의 기여도가 두 공정 모두 95% 이상 이었으며, 지구온난화에 영향을 미치는 단위공정은 전력생산 공정이 A2O공정에서 85%, MBR공정에서 96% 이상 기여하는 것으로 분석됐다. 결과적으로 하수처리시설의 경우 처리공법에 따라 배출되는 수계오염물질량과 처리공정에 사용되는 전력사용량이 가장 중요한 기여 요소(Key Contributor)인 것으로 판단된다. 현재 하수처리공법은 공법별 처리효율성과 유지관리비 등의 비용을 고려하여 평가되고 있다. 하지만 전력소모량이 하수처리시설의 유지비용 측면에만 고려될 경우, 지구온난화에 미치는 부정적인 환경영향을 간과할 수 있다는 점을 알 수 있었다. 중요한 국가기반시설의 하나인하수처리시설의 처리기능에 대한 효율성 향상과 함께 지속가능한 기반시설로서의 역할을 위해서는 전과정에 대한 환경성 분석을 고려하는 것이 필요할 것으로 사료된다.

생물담체 공정을 기반으로 한 생물학적 질소 제거의 기술 개발 동향: 리뷰

( Jesmin Akter ),( Hiyaw Hatiya Ware ),이재엽 ( Jae-yeop Lee ),김일호 ( Ilho Kim ) 한국물환경학회 2020 한국물환경학회·대한상하수도학회 공동 춘계학술발표회 Vol.2020 No.-

This review paper summarizes biological nitrogen removal based on the bio-media filtration process. Biological filtration using the bio-media filtration technique that utilizes biological micro-organisms to remove nutrients from the wastewater. The main two strategies for the removal of nitrogen from domestic wastewater are nitrification and denitrification. Nitrification is carried out in two steps. First, ammonia (NH3) is converted to nitrite (NO2 -) by ammonia-oxidizing bacteria (AOB) and the second step, nitrite-oxidizing bacteria (NOB) convert nitrite to nitrate (NO3 -). Denitrification is an anoxic process whereby NO3 - is converted to nitrogen gas (N2) by heterotrophic microorganisms using a carbon source as the electron donor. In domestic wastewater, nitrogen originates from waste products of the human body and other organic waste materials. Because eutrophication and nitrate is a risk to human health, the removal of nitrogen from wastewater has become a worldwide concern. A recent study has been shown that various bio-media efficiently used for nitrification and denitrification process, also the growth of biofilm is the potential for ammonia removal. Therefore, the specific surface area of bio-media is available for bio-film growth depends on media types and texture influenced nitrification. The objective of this paper is to describe the bio media treatment process in the biological treatment system for sustainable development in the nitrogen removal process.

생물담체 공정을 기반으로 한 생물학적 질소 제거의 기술 개발 동향: 리뷰

( Jesmin Akter ),( Hiyaw Hatiya Ware ),이재엽 ( Jae-yeop Lee ),김일호 ( Ilho Kim ) 한국물환경학회 2020 한국물환경학회·대한상하수도학회 공동 춘계학술발표회 Vol.2020 No.-

This review paper summarizes biological nitrogen removal based on the bio-media filtration process. Biological filtration using the bio-media filtration technique that utilizes biological micro-organisms to remove nutrients from the wastewater. The main two strategies for the removal of nitrogen from domestic wastewater are nitrification and denitrification. Nitrification is carried out in two steps. First, ammonia (NH3) is converted to nitrite (NO2 -) by ammonia-oxidizing bacteria (AOB) and the second step, nitrite-oxidizing bacteria (NOB) convert nitrite to nitrate (NO3 -). Denitrification is an anoxic process whereby NO3 - is converted to nitrogen gas (N2) by heterotrophic microorganisms using a carbon source as the electron donor. In domestic wastewater, nitrogen originates from waste products of the human body and other organic waste materials. Because eutrophication and nitrate is a risk to human health, the removal of nitrogen from wastewater has become a worldwide concern. A recent study has been shown that various bio-media efficiently used for nitrification and denitrification process, also the growth of biofilm is the potential for ammonia removal. Therefore, the specific surface area of bio-media is available for bio-film growth depends on media types and texture influenced nitrification. The objective of this paper is to describe the bio media treatment process in the biological treatment system for sustainable development in the nitrogen removal process.

Zero Emission Production for Conservation of Water Environment

FUJIE, Koichi 嶺南大學校 環境問題硏究所 1999 環境硏究 Vol.18 No.2

AbstractsThis paper aims to give basic information for the minimization of pollution load to environment by reducing wastewater discharge from production process and by selecting appropriate wastewater treatment processes based on characteristic evaluation of both treatment processes and that of wastewaters. Strategies and methodologies to analyze emissions from the production processes to reduce those by refining and/or replacing the unit process with the alternatives are introduced as well. It was stressed that taking materials and energy balances of the production process are the essential to clarify emissions quantitatively for the reduction of pollutants in the focused process. A procedure including biological degradability, activated carbon adsorption, chemical oxidation for mineralization and for improvement of biodegradability of pollutants, coagulation, and so on, was proposed to evaluate wastewaters for appropriate selection of treatment processes.

생물담체 공정을 기반으로 한 생물학적 질소 제거의 기술 개발 동향: 리뷰

( Jesmin Akter ),( Hiyaw Hatiya Ware ),이재엽 ( Jae-yeop Lee ),김일호 ( Ilho Kim ) 한국물환경학회 2020 한국물환경학회·대한상하수도학회 공동 춘계학술발표회 Vol.2020 No.-

This review paper summarizes biological nitrogen removal based on the bio-media filtration process. Biological filtration using the bio-media filtration technique that utilizes biological micro-organisms to remove nutrients from the wastewater. The main two strategies for the removal of nitrogen from domestic wastewater are nitrification and denitrification. Nitrification is carried out in two steps. First, ammonia (NH3) is converted to nitrite (NO2 -) by ammonia-oxidizing bacteria (AOB) and the second step, nitrite-oxidizing bacteria (NOB) convert nitrite to nitrate (NO3 -). Denitrification is an anoxic process whereby NO3 - is converted to nitrogen gas (N2) by heterotrophic microorganisms using a carbon source as the electron donor. In domestic wastewater, nitrogen originates from waste products of the human body and other organic waste materials. Because eutrophication and nitrate is a risk to human health, the removal of nitrogen from wastewater has become a worldwide concern. A recent study has been shown that various bio-media efficiently used for nitrification and denitrification process, also the growth of biofilm is the potential for ammonia removal. Therefore, the specific surface area of bio-media is available for bio-film growth depends on media types and texture influenced nitrification. The objective of this paper is to describe the bio media treatment process in the biological treatment system for sustainable development in the nitrogen removal process.