• Membrane Journal
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• v.5 no.4
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• pp.137-144
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• 1995

This studies concern the separation of aqueous boric acid solution and same solution containing silica using cellulose acetate RO S/W 4040 module manufactured by Hydranautics Co. The operating conditions of the applied pressures, temperatures, and feed flow rate are also investigated to characterize the permeabilities, biroc acid recovery, and silica rejection, so that the optimum operating conditions would be found out. In the case where the operating conditions are the temperature 35$^{\circ}$C, The pressure 20atm, and the feed flow rate 2.82 l/min, for the boric acid aqueous solution, the boric acid recovery 58.7% and the permeation rate 2.82 l/min were obtained. And also the results showed the boric acid recovery 68.1% and the permeation rate 1.56 l/min at the operating conditions, 35$^{\circ}$C and 10atm. For the boric acid solution containing silica, when the feed solution are at the conditions of 35$^{\circ}$C and 3.2atm, the boric acid recovery 69.7%, the silica rejection 97.5% and the permeation rate 0.47 l/min were obtained. And the operating conditions were at 35$^{\circ}$C, 20atm and the feed flow rate 2.92 l/min, the results showed the boric acid recovery 56.4%, the silica rejection 96.1% and the permeation rate 2.72 l/min.

• Journal of the Korean Applied Science and Technology
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• v.33 no.4
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• pp.795-801
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• 2016

This study is on the denitrification process using the sodium alginate and $CaCl_2$ as a flocculant. Removal techniques of nitrate nitrogen from waste water are reverse osmosis, ion exchange, electro dialysis and biological method etc. We tried to remove nitrate nitrogen with flocculation and sedimentation method in the present study. Calcium alginate is expected to form a chelate bond with nitrate nitrogen in the solution. So the effects of flocculantt component, flocculation reaction time, molar ratio of the flocculant, flocculant injection rate are studied to determine the best removal rate of nitrate nitrogen. In addition, we tried to determine the nitrate nitrogen removal mechanism by analyzing the structure and component ratio of the configuration after the agglutination precipitate by FE-SEM and EDS. As a result, the nitrate nitrogen removal mechanism is turned out to form calcium-nitro-alginate, and the best mole ratio of flocculating agent is 1 : 1, the injection rate of the flocculant was up to 2%, the removal rate of the nitrate nitrogen to be 56.7% in the synthetic wastewater.

• Journal of Animal Environmental Science
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• v.14 no.2
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• pp.119-128
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• 2008

This experiment was conducted to investigate the effects of concentrated pig slurry using membrane filter on growth of tomato in nutriculture. Pig slurry was filtered by ultra filtration and concentrated by reverse osmosis process. Filtration of pig slurry was necessary to prevent the hose clogging in nutriculture. The concentrated pig slurry (CS) and nutrient solution (NS) were mixed by six different mixing ratios of 0:100, 20:80, 40:60, 60:40%, 80: 20 and 100%:0% based on nitrogen content. The chemical nutrient solution was the solution of National Horticulture Research Station for the growth of tomato. The concentration of nutrient solution was adjusted a range of $1.6{\sim}2.0mS/cm$ in EC. The plant height of tomato treated with CS 20+NS 80% was similar with NS 100% control plot. Plant height was highest in the plot of CS 20+NS 80%. The treatment of 100% concentrated pig slurry was lowest in the gowth characteristics of tomato. Number of cluster was very lower in 100% concentrated pig slurry compared with plot of chemical nutrient solution. In the beginning of growth stage, SPAD reading value was reduced in plot treated with CS 100%, but CS 20+NS 80% plot was higher compared to 100% concentrated pig slurry. SPAD value of tomato leaves was decreased as the amount of CS was increased. The SPAD value also in treatment of concentrated pig slurry was lower in the middle growth stage compared to control plot. The dry weight of stem and leaf were 107.4, 104.2g in plot of NS 100% and CS 20%+NS 80%, respectively. The fruit number and weight were decreased at high application plots of concentrated pig slurry, The fruit setting of tomato showed lowest in the plot treated with 100% concentrated pig slurry, and the growth of tomato severely decreased after application of 100% CS treatment. In conclusion, the growth characteristics such as plant height and fruit weight of tomato were not significantly different between the plots treated with mixture of 20% CS +80%NS and 100% nutrient solution treatment. In conclusion, the mixture solution of 20% of concentrated pig slurry and 80% of nutrient solution could be used as a nutrition solution of tomato nuticulture.