Fouling is an inevitable problem in membrane water treatment plant. It can be measured by trans-membrane pressure (TMP) in the constant flux operation, and chemical cleaning is carried out when TMP reaches a critical value. An early fouilng alarm is defined as warning the critical TMP value appearance in advance. The alarming method was developed using one of machine learning algorithms, decision tree, and applied to a ceramic microfiltration (MF) pilot plant. First, the decision tree model that classifies the normal/abnormal state of the filtration cycle of the ceramic MF pilot plant was developed and it was then used to make the early fouling alarm method. The accuracy of the classification model was up to 96.2% and the time for the early warning was when abnormal cycles occurred three times in a row. The early fouling alram can expect reaching a limit TMP in advance (e.g., 15-174 hours). By adopting TMP increasing rate and backwash efficiency as machine learning variables, the model accuracy and the reliability of the early fouling alarm method were increased, respectively.

Eutrophication and algal blooms can lead to increase of taste and odor compounds and health problems by cyanobacterial toxins. To cope with these eco-social issues, Ministry of Environment in Korea has been reinforcing the effluent standards of wastewater treatment facilities. As a result, various advanced phosphorus removal processes have been adopted in each wastewater treatment plant nation-widely. However, a lot of existing advanced wastewater treatment processes have been facing the problems of expensive cost in operation and excessive sludge production caused by high dosage of coagulant. In this study, the sedimentation and dissolved air flotation (SeDAF) process integrated with sedimentation and flotation has been developed for enhanced phosphorus removal in wastewater treatment facilities. Design and operating parameters of the SeDAF process with the capacity of 100 m3/d were determined, and a demonstration plant has been installed and operated at I wastewater treatment facility (located in Gyeonggi-do) for the verification of field applicability. Several empirical evaluations for the SeDAF process were performed at demonstration-plant scale, and the results showed clearly that T-P and turbidity values of treated water were to satisfy the highest effluent standards below 0.2 mg/L and 2.0 NTU stably for all of operation cases.

A 1,000 m3/d DAF(dissolved air flotation) pilot plant was installed to evaluate the performance of the floating process using the Nakdong River. Efficiency of various DAF operations under different conditions, such as hydraulic loading rate, coagulant concentration was evaluated in the current research. The operation conditions were evaluated, based on the removal or turbidity, TOC(total organic carbon), THMFP(trihalomethane formation potential), Mn(manganese), and Al(aluminum). Also, particle size analysis of treated water by DAF was performed to examine the characteristics of particles existing in the treated water. The turbidity removal was higher than 90%, and it could be operated at 0.5 NTU or less, which is suitable for the drinking water quality standard. Turbidity, TOC, and THMFP resulted in stable water quality when replacing the coagulant from alum to PAC(poly aluminum chloride). A 100% removal of Chl-a was recorded during the summer period of the DAF operations. Mn removal was not as effective as where the removal did not satisfy the water quality standards for the majority of the operation period. Hydraulic loading of 10 m/h, and coagulant concentrations of 40 mg/L was determined to be the optimal operating conditions for turbidity and TOC removal. When the coagulant concentration increases, the Al concentration of the DAF treated water also increases, so coagulant injection control is required according to the raw water quality. Particle size distribution results indicated that particles larger than 25 μm showed higher removal rates than smaller particles. The total particel count in the treated water was 2,214.7 counts/ml under the operation conditions of 10 m/h of hydraulic loading rate and coagulant concentrations of 60 mg/L.

압출성형 결과 최근 관심이 많은 구증구포 흑삼에 함유 되는 진세노사이드인 Rg2, Rg5 등의 함량이 바렐온도가 높은 조건에서 매우 많이 증가되는 결과를 볼 수 있다 기존의 연구는 실험실 수준의 압출 성형기를 사용하였으나 산업화가 가능한 pilot-scale 설비를 사용하여 scale-up 공정의 가능성을 확인하였다. 또한 preconditioner를 활용하여 압출성형 전에 수증기에 의한 수화 및 열처리를 통해서 보다 효율적인 인삼 가공공정이 가능한 공정으로 운영하였다. 압출성형 결과 최근 관심이 많은 구증구포 흑삼에 함유되는 진세노사이드인 Rg2, Rg5 등의 함량이 바렐온도가 높은 조건에서 매우 많이 증가되는 결과를 볼 수 있다. 이는 pilot scale twin-screw extruder 설비를 활용한 공정이 인삼의 가공 공정으로 산업화에 유용하게 사용될 수 있는 결과라 사료된다.

This study deals with the microstructure and tensile properties of 600 MPa-grade seismic reinforced steel bars fabricated by a pilot plant. The steel bar specimens are composed of a fully ferrite-pearlite structure because they were air-cooled after hot-rolling. The volume fraction and interlamellar spacing of the pearlite and the ferrite grain size decrease from the center region to the surface region because the surface region is more rapidly cooled than the center region. The A steel bar specimenwith a relatively high carbon content generally has a higher pearlite volume fraction and interlamellar spacing of pearlite and a finer ferrite grain size because increasing the carbon content promotes the formation of pearlite. As a result, the A steel bar specimen has a higher hardness than the B steel bar in all the regions. The hardness shows a tendency to decrease from the center region to the surface region due to the decreased pearlite volume fraction. On the other hand, the tensile-to-yield strength ratio and the tensile strength of the A steel bar specimen are higher than those of the B steel bar with a relatively low carbon content because a higher pearlite volume fraction enhances work hardening. In addition, the B steel bar specimen has higher uniform and total elongations because a lower pearlite volume fraction facilitates plastic deformation caused by dislocation slip.

This study evaluated the ecotoxicological properties of livestock waste water treated by a LID (Low Impact Development) system, using a mixture of bio-reeds and bio-ceramics as suitable bed media for a subsequent treatment process of a livestock wastewater treatment plant. The relationship between the pollutant reduction rate and the ecotoxicity was analyzed with the effluents from the inlet pilot plant, with vegetated swale and wetlands and the batch type of an infiltration trench. Each pilot plant consisted of a bio process using bio-reeds and bioceramics as bed media, as well as a general process using general reeds and a bed as a control group. The results indicated that, after applying the HRT 24 hour LID method, the ecotoxicity was considerably lowered and the batch type pilot plant was shown to be effective for toxicity reduction. The LID method is expected to be effective for water quality management, considering ecotoxicity by not only as a nonpoint source pollution abatement facility but also, as a subsequent treatment process linked with a livestock manure purification facility. It is necessary to take the LID technic optimization study further to apply it as a subsequent process for livestock wastewater treatment.

식품 포장재 내 곤충 침입을 방지하기 위해 방향유를 함유한 방충 필름이 연구되고 있으나 파일럿 규모의 생산 장비를 이용한 연구는 드물다. 따라서 본 연구의 목적은 파일럿 규모의 생산 장비로 미세캡슐화된 시나몬방향유(cinnamon oil, CO) 함유 식품 포장 필름을 개발하고 필름의 방충효과와 이화학적 특성을 평가하는 것이었다. 모든 필름은 파일럿 규모의 그라비아 인쇄기(Roto Gravure Printing Press, Ilsung Machinary Co., Ltd., Gumi, Korea)와 적층기(Dry laminating & Extrusion laminating machine, INT CO., Ltd; Ansan, Korea)로 제작되었다. 폴리비닐알코올 수용액(0.02%, w/w, 폴리비닐알코올/증류수)을 사용하여 CO (5.2%, w/w, CO/PVA 수용액) 미세캡슐 에멀션을 제조하였고, 0,1 또는 2% (w/w, CO/미세캡슐 CO 에멀션)의 미세캡슐 CO 에멀션을 잉크(54 또는 61%, w/w, 잉크/전체 혼합액)와 시너(thinner) (23 또는 26%, w/w, 시너/전체 혼합액)에 혼합하여 인쇄 용액을 만들었다. 만들어진 용액을 폴리프로필렌필름(30 μm)에 그라비아 인쇄기로 인쇄한 후, 인쇄된 면에 저밀도폴리에틸렌 필름(40 μm)을 올려놓고 적층(lamination)하여 방충 필름(75 μm 두께)을 제작하였다. 소규모와 파일럿 규모로 진행된 필름의 방충효과 측정에는 화랑곡 나방(Plodia interpunctella) 유충을 사용하였고, 개발된 필름의 시남알데하이드 방출률, 인장 및 수분 차단 특성 그리고 열 중량을 분석하였다. 파일럿 규모 인쇄기와 적층기는 미세캡슐 CO 에멀션이 사용된 방출필름을 연속적이고 균일하게 생산하였다. 미세캡슐 2% CO 에멀션 제형으로 제작된 필름이 가장 높은 방충능을 보였으며, 미세캡슐화가 방충효과를 유지하면서 시남알데하이드의 보존성을 높여 방충효과를 유지하는 데 효과적임을 알 수 있었다. 열 중량분석 결과를 통해 미세캡슐화와 적층이 CO의 휘발을 막는 데 효과적임을 확인했다. 필름의 인장강도, 신장률, 탄성률 그리고 수증기 투과성은 각각 40.4-45.4 MPa, 87.1-87.6%, 831.8-838.1 MPa, 그리고 0.0078-0.0082 g·mm·h-1·kPa-1·m-2이 었으며, 이 결과들은 개발된 방충 필름의 인장 및 수분특성에 변화를 주지 않는 것으로 관찰되었다(p>0.05). 연구를 통해 파일럿 플랜트 규모에서 방충 필름을 성공적으로 제작할 수 있었고, 방충효과와 이화학적 특성 결과를 통해 제작된 방충 필름의 상업적 적용 가능성을 확인할 수 있었다.

Medium pressure and mixed enzyme were used to hydrolyze raw anchovy under controlled conditions at a batchpilot plant-scale process for the production of anchovy protein hydrolysates (APH). Mass balance calculations were carried out so that the degree of protein solubilization and yields could be estimated. Almost complete hydrolysis could be achieved in 12 h, at 50oC and 75 MPa, with no pH adjustment, at 1% (10 g/kg) mixed enzyme using raw anchovy. This was achieved with the addition of water (1/2 raw anchovy/water). The degrees of protein solubilization and yield were 63.50% and 55.61%, respectively. Fractionation using UF/NF pilot scale systems was carried out for producing four different fractions on the APH. Successive fractionation on UF and NF membranes allowed the concentration of the peptides of selected sizes without, however, carrying out sharp separations, and with some MW classes being found in several fractions. Spray drying processes for 10 kDa permeate were described to increase their usability. The free amino acid profile of the fractions was identical to that of the APH.

본 연구는 RO 공정을 통한 해수담수화 플랜트의 에너지 저감을 위한 FO/RO hybrid pilot plant 실증 연구에 관한 것이다. 폐수처리 방류수를 이용하여 FO 공정을 통해 해수를 희석시키고, 희석된 해수는 RO 공정을 통해 담수를 생산하는 공정으로 폐수재이용과 저에너지 담수화를 목적으로 하였다. 이 공정은 RO 공정에 유입되는 해수의 염도가 낮아지기 때문에 담수화 에너지를 획기적으로 낮추는 것이 가능하다. 운전된 system은 유입수 기준 1ton/hr의 처리용량을 가 지는 FO/RO hybrid 공정으로 화력발전소 내의 해수담수화 설비내에서 운전하였다. 이를 통하여 기존 RO system 대비 약 20~30%정도의 에너지 소비 저감 효과 및 RO의 fouling 개선 효과가 있음을 확인하였다.

In the current study, oxidative decomposition of a volatile organic compound was investigated at room temperature and pressure. The experiment was carried out in lower ethylene concentration and with various higher gas flow rates. The reactor has 7 different compartments in which the reaction takes place independently. Plasma was generated inside each compartment by the application of alternating current (AC) voltage. 5 wt% manganese loaded and 5 wt% silver loaded 13X zeolite were used as catalysts. Bare zeolite showed higher ethylene decomposition efficiency than Ag loaded and Mn loaded zeolite. Ozone concentration was increased slightly while increasing the SIE, reached a maximum and started decreasing. Ag loaded zeolite also showed similar decomposition efficiency, but the concentration of ozone was greatly lowered.

본 연구에서는 건축폐기물로 분류되는 레미콘회수수를 재활용함과 동시에 지구온난화의 주범 인 CO2의 자원화를 위한 시스템의 공정최적화를 진행하였다. 레미콘회수수를 이용한 액상탄산화 반응에 서 가장 중요한 공정은 Ca2+를 용출하는 공정이다. 일정량의 레미콘회수수를 이용해 고순도의 CaCO3을 생성하기 위해 Ca2+ 용출시 질산에 의해 낮아지는 pH 농도를 기준으로 실험을 진행하였으며, CO2는 발전기 배기가스를 이용해 MEA용액에 포집하였다. 본 연구를 통해 1톤의 레미콘회수수에서 최대 11 kg의 CaCO3를 합성할 수 있었다. 생성된 CaCO3 분석결과 제지용으로 사용 가능한 것을 확인하였다.

Various studies have forwarded an outstanding wastewater effluent treatment systems toward securing sustainable supply of water sources. In this paper, a broad overview of the performance of MF membrane as pretreatment option for wastewater reuse will be presented based on the literature survey and experiments conducted over the wastewater reuse pilot plant. The pilot plant was operated with a continuous data acquisition for about 300days under various chemical enhanced backwash (CEB) system with subsequent treated water quality analysis. Accordingly, assessment of the effluent revealed that the pretreated water is suitable enough to be used as an input for Reverse Osmosis (RO) unit and significant effect of CEB and concentration of NaOCl is also conceived from the analysis. Moreover, it's also observed that the application of various CEB condition over long operational hours induced a constant declination of overall performance of MF membrane.

A microencapsulated cinnamon oil (CO)-coated film was developed using a pilot-plant scale film coating system. CO microencapsulated with polyvinyl alcohol was incorporated with a printing ink and the ink mixture was applied to the surface of a polypropylene (PP) film as an ink coating using a gravure printing press at a speed of 20-200 m/min. The tensile strength, percentage elongation at break, elastic modulus, and water vapor permeability of the PP films with and without coating with the microcapsules were not significantly different (p > 0.05), which indicates that the coating did not alter those properties of the films. Microencapsulation effectively prevented the volatilization of CO in the films. The microencapsulated system may be extended to other food-packaging films for which the same ink-printing platform is used. The results from this study imply that the oil-microencapsulated films could be potentially produced by a modern film manufacturing system.

The excessive concentration of phosphorus in the river and reservoir is a deteriorating factor for the eutrophication. The converter slag was used to remove the phosphate from the synthetic wastewater. Influencing factors were studied to remove soluble orthophosphate with the different particle sizes through the batch and the column experiments by continuous flow. Freundlich and Langmuir adsorption isotherm constants were obtained from batch experiments with PSA and PSB. Freundlich isotherm was fitted better than Langmuir isotherm. Regression coefficient of Freundlich isotherm was 0.95 for PSA and 0.92 for PSB, respectively. The adsorption kinetics from the batch experiment were revealed that bigger size of convert slag, PSA can be applied for the higher than 3.5 mg/L of phosphate concentration. The pilot plant of continuous flow was applied in order to evaluate the pH variation, breakthrough points and breakthrough adsorption capacity of phosphate. The variation of pH was decreased through the experimental hours. The breakthrough time was 1,432 and 312 hours to 10 mg/L and 50 mg/L for the influent concentration, respectively. The breakthrough adsorption capacity was 3.54 g/kg for 10 mg/L, and 1.72 g/kg for 50 mg/L as influent phosphate concentration.

본 연구는 LNG를 연료로 사용하는 화력발전소 보일러에서 배출되는 1,000 Nm3/day의 연소 배가스에 포함된 8 ∼10%의 CO2를 대상으로 순도 99%, 회수율 90%로 회수할 수 있는 실증규모의 다단계 막분리 공정에 관한 운전 결과이다. 이를 위해 본 연구팀에서는 가소화 안정성이 우수한 폴리이서설폰 중공사막을 개발하고 CO2/N2의 분리특성을 연구한바 있 으며[1], 소형 모듈을 이용하여 압력 및 CO2의 조성 변화에 따른 투과 특성을 실험과 향류 방식의 전산 모사를 통하여 확인 하여 막분리에 의한 CO2의 회수 가능성을 확인한 바 있다[2-4]. 이러한 선행 연구결과를 바탕으로 pilot 규모의 다단계 막분 리 plant를 설계하여 제작, 설치, 운전하였으며 그 운전 결과를 다단계 공정의 수치 모사 결과와 비교하였다. 전체 공정은 크게 배출되는 배가스 내의 수분을 전단에서 제거하기 위한 제습 공정과 후단에 재순환이 가능한 4단계 막분리 공정으로 구성되어 있다. 4단 분리막 공정에서 배출되는 최종 CO2의 농도는 운전 조건에 따라 95∼99%의 CO2가 0.15∼0.2 ton/day 의 회수율 70∼95% 회수규모로 얻어졌다. 얻어진 실험 결과는 수치 모사 결과와 비교하였을 때 매우 잘 일치 하는 것을 알 수 있었으며 운전 중 전체 공정은 안정적으로 작동하는 것을 확인할 수 있었다. 본 연구를 통해 다단계 막분리 공정을 통한 배가스에서 CO2를 성공적으로 분리할 수 있었다.

원전의 정상운전이나 해체시 발생될 수 있는 토양의 제염을 위한 토양제염장치를 개발하였으며 실증 실험을 수행하였다. 제염장치를 이용한 제염실험을 종합해본 결과 제염조건에 큰 상관없이 이상의 제염율을 얻을 수 있었다. 방사능 준위 및 토양입도에 의한 실험결과를 보면 낮은 방사능 농도 및 고입도의 제염율이 다소 높음을 알 수 있었다. 제염용액과 토양질량의 비에 따른 제염율은 제염제 부피를 두배로 높였을 경우 방사능 농도가 높은 경우에 큰 것으로 나타났다. 반복 제염은 의 다소 작은 입자에 더욱 효과적으로, 제염이 어려운 작은 입자의 반복제염시 방사능 저감 효과가 비교적 크게 나타났다. 본 오염토양 제염장치를 활용하면 원전에서 발생되는 오염토양의 방사능 농도를 줄일 뿐 아니라 처분양을 줄여 저장공간의 확보에 기여할 뿐만 아니라 향후 원전의 해체시에도 유용하게 활용될 수 있으리라 생각된다.