• Membrane and Water Treatment
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• 제7권2호
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• pp.143-154
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• 2016

Acetic acid can be removed from wastewater by esterification in a membrane reactor. Pervaporation membrane reactor (PVMR) is an alternative process to conventional separation processes. It is an environmentally friendly process. The main advantages of the PVMR are simultaneous water removal and production of an ester economically. In this study, the synthetic wastewater has been used. Esterification reaction of acetic acid with isopropanol has been studied in the presence of tungstosilicic acid hydrate as a catalyst in a batch reactor and in a PVMR. The effects of important operating parameters such as reaction temperature, initial molar ratio of isopropanol to acetic acid and catalyst concentration has been examined. Removal of acetic acid (conversion of acetic acid) was obtained as 85% using a PVMR by removal of water from the reaction mixture.

• 상하수도학회지
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• 제17권4호
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• pp.559-566
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• 2003

From this research, the performances of a sludge reduction in the sewage sludge aerobic digestion was experimented by using a sludge pretreatment and membrane bioreactor. The submerged plate membrane was used as the solid-liquid separation membrane. After drawing small amounts of sludge in a bioreactor and then doing the alkaline treatment and ozone treatment, the sludge was sent to back to the reactor. The HRT in the reactor was set as 5 days and the operation in the reactor was carried out at the DO of 1mg/L on average. After 100 days of operation in the reactor, it was shown that the reduction efficiency of total solids was more than 83%. Most of volatile solids were removed through mineralization, and the considerable portion of the non-volatile solids was dissolved and then flowed out with the effluent. Only about 16.3% of total solids in the sludge was accmulated in the reactor even without the loss of volatile fraction. Also, by deriving nitrification and denitrification in one reactor simultaneously, more than 90% of nitrogen removal effect was realized and the experiment was run smoothly without fouling of membrane, even in the high concentration of MLSS. Based on this experiment, sludge can be reduced considerably at a low HRT by these two newly suggested approach.

• 멤브레인
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• 제28권5호
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• pp.297-306
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• 2018

본 총설은 분리막기술이 적용된 수소생산에 대한 개론으로, 특히, 암모니아를 수소운반체로 이용하는 수소생산에 대한 연구결과를 중점적으로 서술하였다. 암모니아를 수소운반체로 적용한 수소생산은 추가적인 탄소생성이 없다는 점 외에 여러 측면에 있어 이점이 있다. 많은 연구들이 고순도 수소 분리 및 생산을 위한 분리막 개발을 위해 진행되고 있으며, 이들 중 팔라듐을 기본으로 한 분리막(예를 들어, 다공성 세라믹 또는 다공성 금속 지지체와 팔라듐 합금의 얇은 선택층으로 이루어진 분리막)에 대한 연구가 활발하다. 반면에, 효율적인 암모니아 분해를 위해서는 주로 루테늄 촉매가 적용되고 있으며, 루테늄과 지지체 및 촉진제로 이루어진 루테늄에 기반을 둔 촉매에 대한 연구발표가 다수 존재한다. 수소생산을 위한 분리막 반응기 형태로는 충전층, 유동층, 그리고 마이크로반응기 등이 있으며, 이들의 최적화 및 원활한 물질전달 연구는 현재진행형이다. 또한, 높은 암모니아 분해율, 고순도 수소생산 및 높은 수소생산율을 얻기 위해 분리막과 촉매의 다양한 조합에 대한 연구 및 분리막과 촉매의 역할을 동시에 구현할 수 있는 분리막에 대한 연구가 발표되고 있다.

• 한국물환경학회지
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• 제27권1호
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• pp.44-53
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• 2011

Membrane bio-reactor (MBR) has several advantages over the conventional activated sludge process, including a high biomass, low sludge production, and better permeate quality. Therefore, the MBR have gained popularity for municipal and industrial wastewater treatment. However the MBR usually were used for sewage and low streng th wastewater treatment because of membrane fouling problem and limitation of oxygen transfer into biomass. In this study, the hybrid process combining MBR and pure oxygen was tested for high strength organic wastewater treatment in the COD loading range from 2 to $10kgCOD/m^3{\cdot}day$. The hybrid process, membrane coupled pure oxygen high compact reactor (MPHCR), had been operated for one year and operation parameters, the effect of COD loading, MLSS concentration and the location of membrane module were studied for membrane fouling characteristic. Also membrane resistance test and the component of foulant was analyzed to investigate what is specific foulant in the MBR.

• 멤브레인
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• 제15권4호
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• pp.330-337
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• 2005

[ $250^{\circ}C$의 고온에서 수증기 선택 투과 특성을 가지는 silica 막을 메탄을 탈수에 의한 dimethyl ether (DME) 합성 반응에 분리막 반응기로 적용하였다. Silica 전구체로서 tetraethoxysilane (TEOS)을 이용하여 초음파 분무 열분해 및 기상화학 증착법(CVD)법 등에 의해 다공성 스테인레스 스틸(SUS)에 silica 막을 합성하였다. CVD법에 의해 합성한 silica막의 수증기 투과도 및 메탄올에 대한 분리계수 상관관계 trade-off 선이 열분해 silica 막보다 높이 존재하였다. 수증기 투과도가 $1.2\times10^{-7}\;mol\;{\cdot}\;m^{-2}\;{\cdot}\;S^{-1}\;{\cdot}\;Pa^{-1}$ 이상이고, 메탄올에 대한 분리계수가 10 이상의 성능을 가지는 분리막 반응기에 대해서 기존 반응기 대비 $20\%$ 이상 메탄을 전환율이 향상되었다. 고온 수증기 선택성 silica 막이 메탄을 탈수 반응에 의해 생성되는 수증기를 제거함으로서 촉매 활성 저하를 억제하여 반응 전환율을 개선시키는 막 반응기로서의 효과를 확인할 수 있었다.

• 한국막학회:학술대회논문집
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• 한국막학회 2003년도 The 4th Korea-Italy Workshop
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• pp.7-10
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• 2003

Factors affecting filtration performance were investigated in a Sequencing Batch Reactor (SBR) coupled with a submerged microfiltration module. Special bioreactors for aerobic and anoxic phases, respectively, were specifically designed in order to differentiate tile effect of Dissolved oxygen (DO) from that of mixing intensity on membrane filterability. DO concentration as well as mixing intensity proved to have a major influence on the membrane performance regardless of the SBR phase. A higher DO concentration resulted in a slower rise in TMP, corresponding to less membrane fouling.

• 한국막학회:학술대회논문집
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• 한국막학회 2003년도 The 4th Korea-Italy Workshop
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• pp.11-16
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• 2003

A mathematical model describing the performance of a three phase catalytic membrane reactor for the partial oxidation of propane has been developed. The theoretical study pointed out that the recovery of products in the gas phase is strongly related to the membrane hydrophobicity.

• 공업화학
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• 제16권5호
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• pp.641-647
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• 2005

메탄의 부분산화반응은 수소 제조의 중요한 반응 중의 하나이다. 무전해 도금방법에 의해 제조된 팔라듐-은 막을 막반응기(membrane reactor)로서 메탄의 부분산화반응에 적용하여 반응온도, $O_2/CH_4$ 몰비, $CH_4$ 공급속도, $N_2$ 운반 가스 흐름속도 등의 변화에 따라 실험을 수행하였다. 막반응기의 메탄 전환율은 알루미나에 담지된 니켈 촉매를 사용하는 반응조건하에서 $350{\sim}730^{\circ}C$의 반응온도에 따라 증가하는 경향을 보였으며, 특히 $730^{\circ}C$와 $O_2/CH_4$ 몰비 0.5에서 메탄 전환율과 CO 선택도가 가장 높았다. 막반응기의 메탄 전환율은 전통적인 관형반응기와 비교한 결과 반응조건에 따라 10~40% 정도 높았다.

• 한국물환경학회지
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• 제24권3호
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• pp.328-332
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• 2008

This research was about T-N removal efficiency of oxic reactor in which fixed media submerged from Membrane BNR(An+Ax+Ox) process. This experiment was implemented by using fixed media and changing DO concentration in the oxic reactor. Nitrification efficiencies of all modes were more than 98%. When no media was in the oxic reactor, T-N removal efficiency was only 47.4%, while it were shown from 60.3% to 67.4% with packed media, which indicated improved efficiency of 27~42%. The removal efficiencies of TCOD and BOD were more than 89%, 98% respectively, which could satisfy the guideline of advanced sewage reclamation by Department of Environment. When DO concentration in the packed oxic-media tank was 0.5~1.0 mg/L, T-N removal efficiency was low, which resulted from insufficient nitrification in the oxic reactor. Therefore, DO concentration of bulk solution needs to be kept more than 1.0 mg/L to induce higher nitrification efficiency in the reactor in which media was submerged. Also, the selection of DO concentration is important to prevent media from being clogged.

• 멤브레인
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• 제19권1호
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• pp.72-82
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• 2009

A mathematical model was written for simulating the removal of phenol from wastewater in enzyme-loaded membrane reactor (EMR). The numerical simulation program was developed so as to predict the degradation of phenol through an EMR. Numerical model proves to be effective in searching for optimal operating conditions and creating an optimal microenvironment for the biocatalyst in order to optimize productivity. In this study, several dimensionless parameters such as Thiele Modulus (${\phi}^2$, dimensionless Michaelis-Menten constant ($\xi$), Peclet number (Pe) were introduced to simplify their effects on system efficiency. In particular, the study of phenol conversion at different feed compositions shows that low phenol concentrations and high Thiele Modulus values lead to higher reactant degradation.