http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
액상 비료를 유도 용액으로 사용하는 정삼투 기반의 해수 담수화
박성직,안희경,Park, Seong-Jik,An, Hee-Kyung 한국농공학회 2013 한국농공학회논문집 Vol.55 No.2
The present study explored the way to desalinate seawater for agricultural irrigation using forward osmosis (FO) process using liquid fertilizer as draw solution. FO experiments were performed in a cross flow mode using flat sheet FO membrane. The effect of membrane orientation, flow rate, and draw solution concentration on the performance of forward osmosis was investigated by measuring water flux of forward osmosis membrane. The water flux when the draw solution was placed against the membrane active layer was lower than the water flux when the feed solution was placed against the membrane active layer. This results indicated that the decrease of effective osmotic pressure by dilutive internal concentration polarization was less than that by concentrative internal concentration polarization. Increasing flow rate from 66.7 to 133.1 $cm^3$/min resulted in increase of the water flux when the membrane active layer orient to draw solution and feed solution, respectively. The reduction of resistance to water flow increased water flux at higher flow rate. The water flux of FO membrane increased with increasing draw solution concentration from 10000 to 30000 mg/L. The water flux for $KH_2PO_4$ draw solution was similar to that for commercial fertilizer. Optimization of FO process would contribute to economically desalinate brackish water for agricultural use.
3D 프린터를 이용한 회전 버킷이 부착된 저류조의 모형 실험
박성직,이창구,이제명,최원,Park, Seong-Jik,Lee, Chang-Gu,Lee, Jemyung,Choi, Won 한국농공학회 2017 한국농공학회논문집 Vol.59 No.2
Recently climate change and urbananization have been increased surface runoff, resulting in flooding. Retention basins have been constructed to control urban flooding by reducing peak flow rate. Recently, the retention basin plays a role in controlling combined sewer overflows (CSOs) as well as urban flooding. In this study, the retention basin with a rotatable bucket was suggested and scale down experiments was performed for the optimum design of the retention basin. Scaled down model was produced using a 3D printer after it was designed as law of similarity. Two times for operating a rotary bucket is required to sweep out the sediments deposited on the bottom of the basin. Optimized dimensions for the retention basin were width of 5 m, height of 5 m, bucket radius of 0.5 m, and bottom slope of 5.0 %. It can be concluded that the results obtained from this study can be used to design the retention basin with a rotatable bucket which does not require energy to operate.
돌로마이트로 충진된 칼럼에서 박테리아 이동에 관한 동역학적 모델 비교
박성직 ( Seong-jik Park ),이창구 ( Chang-gu Lee ),김성배 ( Song-bae Kim ) 한국농공학회 2015 한국농공학회 학술대회초록집 Vol.2015 No.-
The aim of this study was to compare kinetic models to describe the removal of bacteria (Bacillus subtilis ATCC 6633) using dolomite as a filter medium. Column experiments were performed in step injection mode under various conditions of influent bacterial concentration (0.5-2.0 g/L), flow rate (0.5-1.5 mL/min), and column length (10-30 cm). The highest percentage bacterial removal (R<sub>e</sub>) of 75.2 ± 1.6% was obtained under the following conditions: influent bacterial concentration = 1.0 g/L; flow rate = 0.5 mL/min; column length = 20 cm. The highest column capacity for bacterial removal (q<sub>0</sub>) of 2.126±0.067 mg/g was achieved using an influent bacterial concentration of 2.0 g/L, flow rate of 1.0 mL/min, and column length of 20 cm. Increasing the bacterial concentration and flow rate had a negative effect on R<sub>e</sub>, whereas the q<sub>0</sub> values were positively affected. Increasing the column length produced a positive effect on Re, whereas q<sub>0</sub> declined. Simulation of the breakthrough curves (BTCs) using the Adams-Bohart, Thomas, Yoon-Nelson, and dose-response kinetic models demonstrated that the Adams-Bohart model adequately reproduced the initial part of the BTC, whereas the Thomas and Yoon-Nelson models were suitable for describing the transient stage of the BTC between the breakthrough point and saturation point. Compared to the aforementioned models, the dose-response model produced an adequate simulation of the entire BTC.
Influence of phosphate on bacterial removal in columns of iron-coated sand
박성직 ( Seong Jik Park ),이창구 ( Chang Gu Lee ),김현정 ( Hyon Chong Kim ),한용운 ( Yong Un Han ),최낙철 ( Nag Chul Choi ),김성배 ( Song Bae Kim ) 대한상하수도학회 2007 공동추계 학술발표회 논문집 Vol.2007 No.-
This study investigated the bacterial adhesion to iron-coated sand, focusing on the effect of phosphate concentration on the removal of Escherchia coli. Bacterial mass recoveries decreased as phosphate solution increased from 76.7% to 34.1% over the range of specific phosphate concentration (0, 4, 16ppm) tested. This phenomenon can be attributed to the increment of ionic strength with increase of phosphate concentration, which results in the decrement of the thickness of the electrical double layer around the bacteria and coated sand surfaces. In iron-coated sand, however, bacterial mass recoveries increased from 2.7% to 29.2% as phosphate concentration increased. This result can be explained by phosphate adsorption. Phosphate forms inner-sphere complexes on iron-coated sand surfaces, which can lead to competitive adsorption with bacteria on iron-coated sand.