• Journal of Korean Society of Water and Wastewater
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• v.23 no.4
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• pp.439-446
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• 2009

This study was performed to evaluate SND(simultaneous nitrification and denitrification)efficiency, nitrogen removal efficiency and filtration function of non-woven fabric by using submerging MBR packed with granular sulfur covered with non-woven fabric filter. Synthetic wastewater was used as influent wastewater. Concentration of $NH_4{^+}-N$ in influent was maintained about 40 mg/L and the experiment was performed in four phases according to the flow rate. Nitrogen loading rate divided four phases ranging from $0.04 kg\;NH_4{^+}-N/m^3-day$ to $0.16 kg\;NH_4{^+}-N/m^3-day$. As a result, the maximum $NH_4{^+}-N$ removal rate was accomplished at $0.142 kg\;NH_4{^+}-N/m^3-day$ in nitrogen loading of $0.147 kg\;NH_4{^+}-N/m^3-day$. Nitrification efficiency was higher than 95% in all phases. $NO_3{^-}-N$ loading rate was adjusted ranging from $0.22 kg\;NO_3{^-}-N/m^3-day$ to $0.89 kg\;NO_3{^-}-N/m^3-day$. The maximum $NO_3{^-}-N$ removal rate was accomplished up to $0.71 kg\;NO_3{^-}-N/m^3-day$ in $NO_3{^-}-N$ loading of $0.89 kg\;NO_3{^-}-N/m^3-day$. The maximum $NO_3{^-}-N$ removal efficiency was 95% in $NO_3{^-}-N$ loading of $0.22 kg\;NO_3{^-}-N/m^3-day$. T-N removal rate was 90% and concentration of T-N in effluent was 3.7 mg/L in T-N loading rate of $0.039 kg\;NO_3{^-}-N/m^3-day$. In this study, TMP in reactor with and without non-woven fabric filter were observed to define fouling of hollow-fiber membrane module. Reaching time to standard washing pressure(22 cm Hg) of two reactors were 29 days with non-woven fabric But the reactor without non-woven fabric reached standard washing pressure only after 4 days. Accordingly, non-woven fabric was demonstrated the superiority as a filtration ability. With high nitrogen removal rate and decreasing of fouling of membrane, MBR packed with granular sulfur covered with non-woven fabric filter submerging in activated sludge aeration tank can be used as an advanced treatment process.

• Proceedings of the Membrane Society of Korea Conference
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• 2003.11a
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• pp.154-154
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• 2003

세계의 특허동향을 분석해 보면 수처리용 MF/UF 분리막의 제조 및 응용에 관한 연구개발이 매우 활발하게 진행되어져 왔음을 알 수 있다. 또한 다국적 기업들의 적극적인 마케팅과 분리막 공법의 우수한 처리효율이 인정되면서 90년대 후반부터는 수십만톤/일 규모의 징수처리 및 하수고도처리 분야에까지 MF/UF 분리막이 괄목할만한 수요의 증대를 보이고 있으며 이러한 추세는 앞으로도 더욱 확대될 것으로 전망이 되고 있다. 고분자재료를 이용하여 MF/UF 분리막을 제조하는 방법으로는 보편적으로 첫째, 고분자를 용매에 녹인 후 용매와 비 용매간의 상호교환을 유도하여 분리막을 제조하는 상전이법(Phase Inversion). 둘째, 고분자를 고온에서 희석제와 melt-blending 한 후 가해진 열을 제거하면서 상분리를 일으켜 다공성을 부여하는 열유도 상분리법(TIPS, Thermally Induced Phase Separation). 셋째, 결정성 고분자를 용융, 압출 및 냉각하여 결정화도가 매우 높은 전구체를 제조한 후 연신에 의해 비결정 영역을 개열시켜 기공을 형성하는 연신법(Stretching process)이 있다. 이 중 물성이 매우 우수한 폴리올레핀계 결정성 고분자를 이용하여 분리막을 제조할 수 있는 방법은 열유도 상분리법 및 연신법에 제한된다. 본 연구 발표에서는 세계적으로도 극소수의 기업들만이 보유하고 있으며 고도로 축적된 노하우를 필요로 하는 열유도 상분리법 및 연신법에 의하여 폴리프로필렌 및 폴리에틸렌 중공사막을 제조하는 방법과 이 두 가지 방법에 의해서 제조된 중공사막의 구조, 물성 및 수투과 성능 그리고 KMS 중공 사막의 응용사례를 통한 실제 운전특성 등을 소개하고자 한다.좋은 결과를 가져다 주는 술식으로 판단되었다.결과를 이용하여 향후 전개될 홈 네트워크 서비스 및 관련시장의 발전 방향을 전망해 보고 이에 따른 기업이나 정부차원의 대응전략을 파악하고자 한다.육구에서는 큰 변화를 나타내고 있지 않았다(p<0.05). 운동과 비운동시킨 참돔의 지질 함량의 변화는 운동시킨 참돔은 운동으로 인한 에너지 소비로 인하여 함량이 유의적으로 감소했으며(r=-0.35), 비운동사육구에서는 절식으로 인하여 지질함량이 감소하였다(r=-0.38). 파괴강도와 가장 밀접한 영향을 가지는 콜라겐은 운동과 비운동 모두 사육기간동안 큰 변화는 보이지 않았다. 초기의 파괴강도값은 1.45±0.02kg(운동사육구), 1.36±0.18kg(비운동사육구)이였으며 사육기간동안 운동사육구는 파괴강도값이 증가한 반면, 비운동수조에서는 참돔의 파괴강도는 사육기간동안 큰 유의차가 없었다. 각 성분간의 상관도를 살펴보면, 수분함량과 파괴강도는 상관성을 가졌으며, 지질함량과 파괴강도도 같은 경향은 나타내었다. 운동기간동안의 파괴강도와 콜라겐 사이에는 상관성의 거의 없었다. 이는 운동기간에 따른 파괴강도의 증가가 콜라겐의 함량의 증가보다는 지질함량의 감소와 수분함량의 증가와 같은 성분과의 상관성이 크다고 판단된다. 다음으로는, 운동횟수에 의한 영향으로써 운동시간을 1일 6시간으로 설정하여, 운동횟수를 결정하기 위하여 오전, 오후에 각 3시간씩 운동시키는 방법과 오전부터 6시간동안 운동시키는 두 방법을 이용하여 품질을 비교하였다. 각 조건에 따라 운동시킨 참돔의 수분함량을 나타낸 것으로, 2회(오전 3시간, 오후 3시간)에 나누어서 운동시키기 위한 육의 수분함량은 73.37±2.02%를 나타냈으며, 1회(6시간 운동)

• Journal of Korean Society of Environmental Engineers
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• v.38 no.12
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• pp.656-661
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• 2016

Manufacturing membrane materials with high selectivity and permeability is quite desirable but practically not possible, since the permeability and selectivity are usually inversely proportional. From the viewpoint of reducing the cost of $CO_2$ capture, module performance is even more important than the performance of membrane materials itself, which is affected by the permeance of the membrane (P, stagecut) and selectivity (S). As a typical example, when the mixture with a composition of 13% $CO_2$ and 87% of $N_2$ is fed into the module with 10% stage cut and selectivity 5, in the 10 parts of the permeate, $CO_2$ represents 4.28 parts and $N_2$ represents 5.72 parts. In this case, the $CO_2$ concentration in the permeate is 42.8% and the recovery rate of $CO_2$ in this first separation appears as 4.28/13 = 32.9%. When permeance and selectivity are doubled, however, from 10% to 20% and from 5 to 10, respectively, the $CO_2$ concentration in the permeant becomes 64.5% and the recovery rate is 12.9/13 = 99.2%. Since in this case, most of the $CO_2$ is separated, this may be the ideal condition. For a given feed concentration, the $CO_2$ concentration in the separated gas decreases if permeance is larger than the threshold value for complete recovery at a given selectivity. Conversely, for a given permeance, increasing the selectivity over the threshold value does not improve the process further. For a given initial feed gas concentration, if permeance or selectivity is larger than that required for the complete separation of $CO_2$, the process becomes less efficient. From all these considerations, we can see that there exists an optimum design for a given set of conditions.

• Korean Journal of Food Science and Technology
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• v.30 no.5
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• pp.1146-1151
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• 1998

To prevent deterioration of the jujube wine quality by using heat sterilization while commercial production, ultrafiltration and microfiltration were applied. The permeate flux and physicochemical properties of jujube wine determined by MF and UF membrane ($0.2\;{\mu}m$ pore size and 50 K dalton cut off) were investigated. The permeate flux increasing caused the increased operating pressure. The Hunter L value of jujube wine treated MF and UF was increased and that of b value was decreased. The turbidity of jujube wine treated MF and UF was largely decreased. And the values of pH, ethanol, total acid and soluble solid were decreased or were at the same level comparing with untreated jujube wine. Retention percentage of sugar and organic acid was more than 80% and was not influenced by operating pressure. Results of sensory evaluation indicated that the color of UF was superior to un-treatment and commercial ones. And the flavor and taste were not significantly different with untreated jujube wine. The quality deterioration of commercial jujube wine could be improved by MF and UF. According to the sensory evaluation, there was also not difference between MF and UF for preference test. Therefore, the quality of jujube wine could be improved by MF having better separation yield efficiency than UF.

• Journal of Biomedical Engineering Research
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• v.21 no.3 s.61
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• pp.311-320
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• 2000

In this paper a newly designed oxygenator module was used to perform the experiments for pressure drop and oxygen transport in order to evaluate the efficiency of the artificial lung. Also, distilled water. sodium sulfite solutions used in this experiment were evaluated for the performance of other artificial lungs. Substituted bloods have many advantages over whole blood in studying pressure drop and oxygen uptake. They are relatively inexpensive, and require fewer variables to be controlled. Furthermore, deoxygenation is not necessary when those solutions are used. In addition to these advantages. assays and interpretation of the experimental results are relatively easy. In the case of using the sodium sulfite solution having the same oxygen partial pressure as whole blood. the oxygen transfer rate of the sodium sulfite solution was basically same as that of whole blood. It was concluded in evaluating the function of artificial lungs that the sodium sulfite solution was suited for measuring oxygen transfer rate. In our module, artificial blood was flowed into the outside of hollow fiber membrane. The artificial lung created in this experiment showed that pressure drop was reduced to $1/3\~1/6$ of that compared to the inside-flow case.