Water Cycle Research Center, National Agenda Research Division, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea; Advanced Environmental Science, Energy Environment Policy & Technology, KU-KIST GreenSchool, Graduate School of Energy and Environment, Korea University, 145 Anam-Ro, Seongbuk-Gu, Seoul, 02841, Republic of Korea.
Department of Civil, Environmental and Architectural Engineering, Korea University, 145 Anam-Ro, Seongbuk-Gu, Seoul, 02841, Republic of Korea.
Water Res. 2020 May 15;175:115677. doi: 10.1016/j.watres.2020.115677. Epub 2020 Mar 2.
Wetting by fouling is phenomenon specific to membrane distillation (MD) and are regarded as challenges to the seawater membrane distillation (SWMD) process. To understand fouling and wetting, the influence of Mg and Sr crystals, which can potentially cause scaling, as well as Ca crystals deposited on the membrane surface were investigated. Mg(OH) and CaSO had significant impact on fouling and wetting. Even if CaCO and SrSO had no effects on fouling and wetting as single salts, CaCO and CaSO were dominant in synthetic seawater without Mg(OH). However, the occurrence of Mg(OH) scales became a cause for concern if Ca ion was removed from seawater for the prevention of fouling and wetting. Therefore, Mg as well as Ca should be removed for proper fouling and wetting control. NaOH/NaCO softening was used for the removal of Ca and Mg ions. In addition, based on the inhibition effects of Mg ions on Ca scales, a new pretreatment method involving the injection of MgCl to increase the Mg /Ca ratio was examined.
结垢润湿是膜蒸馏（MD）特有的现象，被认为是海水膜蒸馏（SWMD）过程的挑战。为了了解结垢和润湿，研究了可能导致结垢的 Mg 和 Sr 晶体以及沉积在膜表面的 Ca 晶体的影响。Mg(OH) 和 CaSO 对结垢和润湿有显著影响。即使 CaCO 和 SrSO 作为单盐对结垢和润湿没有影响，但在没有 Mg(OH) 的合成海水中，CaCO 和 CaSO 是主要的。然而，如果为了防止结垢和润湿而从海水中去除 Ca 离子，那么 Mg(OH) 结垢的发生就令人担忧。因此，为了正确控制结垢和润湿，应该去除 Mg 和 Ca。NaOH/NaCO 软化用于去除 Ca 和 Mg 离子。此外，基于 Mg 离子对 Ca 垢的抑制作用，研究了一种新的预处理方法，即注入 MgCl 以增加 Mg/Ca 比。
