본 연구에서는 지방 산화를 억제하고 품질이 우수한 부세 굴비의 가공법을 개발하기 위해 대두와 멸치의 복합 발효소재를 첨가한 염지제 처리 및 건조 시간에 따른 부세 굴비를 제조하여 품질 특성을 비교하였다. 발효소재 첨가에 따른 염지제와 부세 굴비의 DPPH 및 ABTS 라디칼 소거능은 발효소재의 함량에 따라 증가하였으나, 발효소재 1% 이상에서 부세 굴비의 라디칼 소거능은 유의적인 차이를 보이지 않았다. 발효소재의 함량이 증가할수록 부세 굴비의 아미노태질소 함량은 증가하고 VBN, TBARS, 산가는 감소하는 결과를 나타내나, 발효소재 1% 이상에서 품질의 유의적인 차이가 크지 않으므로 염지제의 발효소재 함량은 1%로 선정하였다. 염지제의 염도에 따른 부세 굴비의 품질을 분석한 결과 염도가 증가할수록 아미노태질소 함량은 증가하고 히스타민, VBN, TBARS, 산가는 감소하는 결과는 나타내며, 염지제의 염도는 품질 개선 효과가 가장 우수한 7% 조건을 선정하였다. 염지 처리 후 건조 시간에 따른 부세 굴비의 품질을 분석한 결 과 건조 시간이 증가할수록 수분은 감소하고 염도, pH, 아미노태질소, 히스타민, VBN, TBARS, 산가는 증가하였다. 그러나 건조 48시간 이하는 수분이 많아 저장성이 낮으며, 건조 96시간에서 히스타민과 산패도의 증가율이 높아지므로 부세 굴비의 건조 시간은 72시간이 적합한 것으 로 판단되었다.

The problem of disposal of brine due to increased MD/RO desalination plant has recently become a big social issue. The chlor-alkali process through electrolysis of brine has been studied as a method to overcome this problem. In order to increase the electrolysis efficiency, a pretreatment process for removal of hard substances must be preceded. In this study, we investigated the mechanism of removal of hardness through chemical precipitation. As a result, Ca was greatly influenced by addition of Na2CO3, and Mg was strongly influenced by pH. Also, the addition of NaOH and Na2CO3 enabled simultaneous removal of Ca and Mg, and showed a removal efficiency of 99.9% or more. Finally, the residual concentrations of Ca and Mg in the brine after the reaction were 0.14 and 0.13 mg/L, respectively. Saturation index was calculated using Visual MINTEQ 3.1, and solid phase analysis of the precipitate was performed by FE-SEM and PXRD analysis. It was confirmed that precipitate formed by the formation of calcite and brucite.

Scale formation is inevitable problem when seawater is treated by vacuum membrane distillation. The reason is the high concentration of calcium ion(Ca2+), sulfate ion(SO4 2-) and bicarbonate ion(HCO3 -). These ions form calcium sulfate(CaSO4) and calcium carbonate(CaCO3) on the membrane. The scale formed on membrane has to be removed, because the flux can be severely reduced and membrane wetting can be incurred. This study was carried out to investigate scale formation and effectiveness of acid cleaning in vacuum membrane distillation for SWRO brine treatment. It was found that permeate flux gradually declined until volume concentration factor(VCF) reached around 1.55 and membrane wetting started over VCF over 1.6 in the formation of precipitates containing CaSO4 during VMD operation. In contrast, when calcium carbonate formed on membrane, permeate flux was gradually reduced until VCF 3.0. The precipitates containing both CaSO4 and CaCO3 were formed on the membrane surface and in the membrane pore.