• 제목/요약/키워드: batch tests

검색결과 261건 처리시간 0.022초

주물사가 포함된 투수반응벽체(PRB)를 이용한 아연으로 오염된 지하수 처리기법 연구 (Remediation of Groundwater Contaminated with Zinc Using Permeable Reactive Barriers Containing Foundry Sands)

  • 이태윤;;박재우
    • 한국지반공학회논문집
    • /
    • 제18권5호
    • /
    • pp.159-167
    • /
    • 2002
  • 아연의 주물사에 대한 분배계수는 주물사에 포함된 TOC, 점토 함량, 총 철 함량 등에 따라 변하고 특히 용액 PH에 큰 영향을 받는 것을 관찰하였다. Batch 실험으로부터 얻어진 경험식으로부터분배계수와 제거상수를 예측할 수 있었다. Batch kinetic 실험과 batch sorption 실험으로부터 얻어진 분배계수는 용액 pH가 같을 시 거의 같은 값을 보이고 있다.

Measurement of Ordinary Heterotrophic Organism Active Biomass in Activated Sludge Mixed Liquor: Evaluation and Comparison of the Quantifying Techniques

  • Lee, Byung Joon;Wentzel, Mark;Ekama, George;Choi, Yun Young;Choi, Jung Woo
    • Environmental Engineering Research
    • /
    • 제19권1호
    • /
    • pp.91-99
    • /
    • 2014
  • Ordinary heterotrophic organism (OHO) active biomass plays key roles in biological wastewater treatment processes. However, due to the lack of measurement techniques, the OHO active biomass exists hypothetically within the design and simulation of biological wastewater treatment processes. This research was purposed to develop a quick and easy quantifying technique for the OHO active biomass applying a modified batch aerobic growth test. Two nitrification-denitrification activated sludge systems, with 10- and 20-day sludge ages, were operated to provide well-cultured mixed liquor to the batch tests. A steady state design model was firstly applied to quantify the "theoretical" OHO active biomass concentration of the two parent systems. The mixed liquor from the parent systems was then inoculated to a batch growth test and a batch digestion test to estimate the "measured" OHO active biomass concentration in the mixed liquor. The measured OHO active biomass concentrations with the batch growth test and the batch digestion test were compared to the theoretical concentrations of the parent system. The measured concentrations with the batch growth test were generally smaller than the theoretical concentrations. However, the measured concentrations with the batch aerobic digestion tests showed a good correlation to the theoretical concentrations. Thus, a different microbial growth condition (i.e., a higher food/biomass ratio) in the batch growth test, compared to the parent system or the batch digestion test, was found to cause underestimation of the OHO active biomass concentrations.

회분식 실험 Substrate/Microorganisms 비에 따른 종속영양미생물의 특이거동 연구 (Abnormal Behavior of Ordinary Heterotrophic Organism Active Biomass at Different Substrate/Microorganisms Ratios in Batch Test)

  • 이병준;;;민경석
    • 한국물환경학회지
    • /
    • 제20권3호
    • /
    • pp.197-205
    • /
    • 2004
  • Batch test methods have developed for a long time to measure kinetic and stoichiometric parameters which are required to perform steady state design and mathematical modelling of activated sludge processes. However, at various So/Xo ratios, abnormal behaviors of ordinary heterotrophic organism in batch tests have been reported in many researches. Thus, in this research, abnormal behaviors of heterotrophs in batch tests were investigated at various So/Xo conditions by measuring and interpreting oxygen utilization rate. As So/Xo ratio increased, the calculated values of maximum specific growth rates, ${\mu}_{H,max}$ and $K_{MP,max}$, increased. However, at a certain point of So/Xo (around 10mgCOD/mgMLAVSS), ${\mu}_{H,max}$ and $K_{MP,max}$ values started to decrease. According to this observation, three prominent behaviours of heterotrophs were identified at various So/Xo conditions. (1) At low So/Xo region (below 5 mgCOD/mgMLAVSS), the oxygen utilization rate of heterotrophs in batch tests were almost stable and consequently yielded lower maximum specific growth rate. (2) At high So/Xo region (up to 5~10 mgCOD/mgMLAVSS), oxygen utilization rate incresed sharply with time and indicated more upward curvature than the predicted OUR with conventional activated sludge model, which consists of single hetetrotrophs group. Thus, in this region, competition model of two organisms, fast-grower and slow-grower, seemed to be appropriate. (3) At extremely high So/Xo region (over 10mgCOD/mgMLAVSS), significant oxygen utilization rate was still observed even after depletion of readily biodegradable COD. This might be caused by retarded utilization of intermediates which were generated by self inhibition mechanism in the process of RBCOD uptake.

평균납기지연 최소화를 위한 배치생산공정의 실시간 로딩전략 (A Real-Time Loading Strategy of Batch Processing Machines for Average Tardiness Minimization)

  • 구평회
    • 대한산업공학회지
    • /
    • 제40권2호
    • /
    • pp.215-222
    • /
    • 2014
  • This paper provides a real-time loading strategy for batch processing machines in which a number of jobs are simultaneously processed as a batch. The batch processing machines can be seen in both manufacturing industries (e.g., semiconductor, automobile and metal working) and service industries (transportation vehicles, mail shipment and theme park). This paper focuses on batch processing machines in semiconductor manufacturing. We present a look-ahead loading strategy for tardiness minimization where future arrivals and due dates are taken into consideration. Simulation tests are performed on the presented strategy and some existing loading heuristics under various production settings with different traffic intensities and forecasting errors. Experimental results show that our strategy provides the performance of good quality.

고리형 에테르의 생물학적 처리 특성 (Removal Characteristics of Cyclic Ethers in Biological Wastewater Treatment System)

  • 이성열;정연구
    • 한국환경과학회지
    • /
    • 제17권3호
    • /
    • pp.343-350
    • /
    • 2008
  • The fate of two cyclic ethers, THF(Tetrahydrofuran) and 1,4-Dioxane, in conventional biological wastewater treatment plants was investigated using sequential activated sludge process. Removal efficiency of THF were about 86% in average, which was greater than that of 1,4-Dioxane, 30%. However, it was not clear whether the removal of cyclic ethers in biological system was caused by microbial activity or not. Thus treatability tests were conducted by batch experiments. The effects of mixing, aeration and the addition of activated sludge on the removal of cyclic ethers were investigated in batch experiments. THF was totally removed by mixing and aeration in 24 hours while removal ratio of 1,4-Dioxane was at most 30% for the same period. This results could be ascribed to the differences in Henry's law constants between the two chemicals. In addition, biological degradation including biosorption was not obviously observed in these batch tests.

A modified simulated annealing search algorithm for scheduling of chemical batch processes with CIS policy

  • Kim, Hyung-Joon;Jung, Jae-Hak
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 제어로봇시스템학회 1995년도 Proceedings of the Korea Automation Control Conference, 10th (KACC); Seoul, Korea; 23-25 Oct. 1995
    • /
    • pp.319-322
    • /
    • 1995
  • As a trend toward multi-product batch processes is increasing in Chemical Process Industry (CPI), multi-product batch scheduling has been actively studied. But the optimal production scheduling problems for multi-product batch processes are known as NP-complete. Recently Ku and Karimi [5] have studied Simulated Annealing(SA) and Jung et al.[6] have developed Modified Simulated Annealing (MSA) method which was composed of two stage search algorithms for scheduling of batch processes with UIS and NIS. Jung et al.[9] also have studied the Common Intermediate Storage(CIS) policy which have accepted as a high efficient intermediate storage policy. It can be also applied to pipeless mobile intermediate storage pacilities. In spite of these above researches, there have been no contribution of scheduling of CIS policy for chemical batch processes. In this paper, we have developed another MSA for scheduling chemical batch processes with searching the suitable control parameters for CIS policy and have tested the this algorithm with randomly generated various scheduling problems. From these tests, MSA is outperformed to general SA for CIS batch process system.

  • PDF

안정화 처리된 비소오염토양의 장기 용출특성 (Long-Term Leaching Characteristics of Arsenic Contaminated Soils Treated by the Stabilization Method)

  • 유찬;윤성욱;백승환;박진철;이정훈
    • 한국지반공학회:학술대회논문집
    • /
    • 한국지반공학회 2008년도 추계 학술발표회
    • /
    • pp.1463-1474
    • /
    • 2008
  • In order to investigate stabilization effect and sustainability on As-contaminated farmland soils which were affected the abandoned mine site and stabilized by zerovalent iron(ZVI) and industrial by-products, batch-scale and pilot-scale tests were carried out. In batch tests, ZVI and industrial by-products(blast furnace slag, steel refining slag and oyster shell powder) were used in treatment materials to reduce the As leaching. Industrial by-products were mixed with As-contaminated soils, in the ratio of 1%, 3%, 5% and 7% on the weight base of dried soil. The results of batch-scale tests was shown that the reduction of As concentration was observed in all samples and it was expected that ZVI and steel refining slag were more effective than other treatment materials to stabilize As compounds. In pilot-scale tests, columns were filled with untreated soils and treated soils mixed with ZVI and steel refining slag in the same mixing ratio of 3%. Distilled water was discharged into the columns with the velocity of 0.3 pore volume/day. During the test, pH, EC, Eh and As concentration were measured in the regular term(1pore volume). after six months, pilot-scale tests were retested to investigate sustainability of treatment materials. As a result, It was shown that the leachate from control column was continuously released during the test period and its concentration was greater than $100ug{\cdot}L^{-1}$ which was exceeded the national regulation of water discharged to river or stream ($50ug{\cdot}L^{-1}$). On the other hand, soil treated with ZVI and steel refining slag showed that the concentrations of leachate were lower than national regulation of water discharged to river or stream. Therefore it was expected that ZVI and steel refining slag could be applied to the farmland site as the alternative treatment materials.

  • PDF

BATCH형 자연형 태양열 온수급탕 시스템의 열적 성능에 관한 실험적 연구 (Experimental Study for Thermal Performance of Batch Type Passive Solar Hot Water System)

  • 강용혁;조일식;윤환기;오정무
    • 태양에너지
    • /
    • 제7권1호
    • /
    • pp.3-13
    • /
    • 1987
  • A batch type passive solar water systems, which perform the dual function of absorbing the solar energy and storing the heated water, have been designed and fabricated for the purpose of side-by-side testing at KIER. The test models included an A, B and C type batch systems which were classified according to the design of box and arrangement of tanks. The year-round performance tests show that B type batch system taken the step-wise tank arrangement indicates 55.7% yearly-average collection efficiency factor and 61% yearly-average maximum collection efficiency factor. Computer-aided-experimental results show that the sufficient hot water can be obtained in the early morning if the glazing is supplemented by a reflector/insulation cover. The thermal performance equation has been developed for the prediction of hourly variation of the water temperature in tank.

  • PDF

영가철 및 산업폐기물을 활용한 비소오염토양의 안정화 효과조사 (Investigation of Stabilization Effect on Arsenic Contamination Soils using Zerovalent Iron and Industrial by-products)

  • 유찬;윤성욱;백승환;박진철;이정훈;임영철;최승진;장민
    • 한국지반공학회:학술대회논문집
    • /
    • 한국지반공학회 2008년도 춘계 학술발표회 초청강연 및 논문집
    • /
    • pp.229-241
    • /
    • 2008
  • In order to investigate stabilization effect on As-contaminated soils treated by zero-valent iron(ZVI) and industrial by-products, batch tests and column tests were carried out with As-contaminated soils collected from farmland around the abandoned mine site. In batch tests, ZVI and industrial by-products(blast furnace slag, steel refining slag and oyster shell powder) were used as treatment materials to reduce As. Industrial by-products were mixed with As-contaminated soils, in the ratio of 1%, 3%, 5% and 7% on the weight base of dried soil. After incubation, all samples showed the reduction of As concentration and it was expected that ZVI and steel refining slag were effective treatment materials to remove As among treatment materials used in batch test. In column tests, columns were made by acrylic with the dimension of diameter=10cm, height=100cm, thickness=1cm and these columns were filled with untreated soils and treated soils mixed with ZVI and steel refining slag(mixing ratio=3%). Distilled water was discharged into the columns with the velocity of 1 pore-volume/day. During test, pH, EC, Eh and As concentration were measured in the regular term(1 pore-volume). As a result, ZVI and steel refining slag were shown 93%, 62% reduction of As concentration respectively by comparison with untreated soils. Therefore, if ZVI and steel refining slag are used as treatment materials in As-contaminated soils, it is expected that the As concentration in soils is reduced effectively.

  • PDF

A Pilot Study for Remediation of Groundwater by Surfactant -Enhanced Soil Flushing

  • Park, Jong Oh;Lee, Dal-Heui
    • 한국지하수토양환경학회지:지하수토양환경
    • /
    • 제21권5호
    • /
    • pp.1-7
    • /
    • 2016
  • The removal of non-aqueous phase liquids (NAPLs) from groundwater using pure water, via pump and treat, is quite ineffective due to their low solubility and hydrophobicity. Therefore, the objectives of pilot tests were to select potentially suitable surfactants that solubilize tetrachloroethylene (PCE) and trichloroethylene (TCE) present as contaminants and to evaluate the optimal range of process parameters that can increase the removal efficiency in surfactant-enhanced soil flushing (SESF). Used experimental method for surfactant selection was batch experiments. The surfactant solution parameters for SESF pilot tests were surfactant solution concentration, surfactant solution pH, and the flow rate of surfactant solution in the SESF pilot system. Based on the batch experiments for surfactant selection, DOSL (an anionic surfactant) was selected as a suitable surfactant that solubilizes PCE and TCE present as contaminants. The highest recovery (95%) of the contaminants was obtained using a DOSL surfactant in the batch experiments. The pilot test results revealed that the optimum conditions were achieved with a surfactant solution concentration of 4% (v/v), a surfactant solution pH of 7.5, and a flow rate of 30 L/min of surfactant solution (Lee and Woo, 2015). The maximum removal of contaminants (89%) was obtained when optimum conditions were simultaneously met in pilot-scale SESF operations. These results confirm the viability of SESF for treating PCE and TCE-contaminated groundwater.