Abstract The use of non-desalinated seawater for mining purposes is not recommendable because of the high salinity and the presence of some ions, that is, Ca2+ and Mg2+, that can hamper the mineral tailings separation process besides being responsible for scaling formation in pipelines and equipment. To remove these ions from seawater, a novel treatment involving a biomineralization process was tested using a fluidized bed bioreactor (FBB) filled with immobilized beads of the halotolerant ureolytic strain Bacillus subtilis LN8B. The FBB was operated in batch mode according to a sequence of six cycles of eight days. The highest efficiency in removing Ca2+ and Mg2+ occurred in the first cycle for both ions, achieving the removal rate of ~100% by day four for Ca2+ and ~80% by day six for Mg2+, respectively. Precipitates from FBB were mainly composed of ~70.2% of hydromagnesite, and ~17.8% of aragonite. Furthermore, the efficiency of biologically pretreated seawater (BSw) was evaluated as mineral tailings sedimentation medium and compared with three types of water: (i) tap water (Tw); (ii) seawater (Sw); and (iii) distilled water, (Dw). The results showed that the settling velocity in BSw was the highest (i.e., 6.23 ± 0.48 m h−1).

中文翻译：

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通过装有枯草芽孢杆菌 LN8B 固定细胞的流化床生物反应器对采矿过程中的海水进行部分脱盐

摘要 不推荐使用非淡化海水进行采矿，因为高盐度和一些离子（即 Ca2+ 和 Mg2+）的存在会阻碍矿物尾矿分离过程，此外还会导致管道和管道中的结垢形成。设备。为了从海水中去除这些离子，使用填充有耐盐尿素分解菌株枯草芽孢杆菌 LN8B 的固定珠的流化床生物反应器 (FBB) 测试了一种涉及生物矿化过程的新型处理方法。FBB 根据 8 天的 6 个周期的顺序以分批模式运行。两种离子在第一个循环中去除 Ca2+ 和 Mg2+ 的效率最高，分别在第四天对 Ca2+ 和 Mg2+ 的去除率分别达到约 100% 和约 80%。FBB 的沉淀物主要由~70.2% 的水菱镁矿和~17.8% 的文石组成。此外，生物预处理海水 (BSw) 的效率被评估为矿物尾矿沉淀介质，并与三种类型的水进行比较：(i) 自来水 (Tw)；(ii) 海水（SW）；(iii) 蒸馏水，(Dw)。结果表明，BSw 中的沉降速度最高（即 6.23 ± 0.48 m h-1）。