Yan Huaxiao, Liu Yuping, Zhang Haojuan, Jin Shengping, Han Zuozhen, Woo Jusun, Tucker Maurice E, Meng Long, Chi Xiangqun, Han Chao, Zhao Yanyang, Zhao Yueming, Zhao Hui
College of Chemical and Biological Engineering, College of Earth Science and Engineering, Shandong Provincial Key Laboratory of Depositional Mineralization and Sedimentary Minerals, Shandong University of Science and Technology, Qingdao 266590, China.
College of Chemical and Biological Engineering, College of Earth Science and Engineering, Shandong Provincial Key Laboratory of Depositional Mineralization and Sedimentary Minerals, Shandong University of Science and Technology, Qingdao 266590, China; Laboratory for Marine Mineral Resources, Center for Isotope Geochemistry and Geochronology, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China.
J Environ Sci (China). 2025 Jan;147:131-152. doi: 10.1016/j.jes.2023.10.014. Epub 2023 Oct 27.
Biomineralization has garnered significant attention in the field of wastewater treatment due to its notable cost reduction compared to conventional methods. The reinjection water from oilfields containing an exceedingly high concentration of calcium and ferric ions will pose a major hazard in production. However, the utilization of biomineralization for precipitating these ions has been scarcely investigated due to limited tolerance among halophiles towards such extreme conditions. In this study, free and immobilized halophiles Virgibacillus dokdonensis were used to precipitate these ions and the effects were compared, at the same time, biomineralization mechanisms and mineral characteristics were further explored. The results show that bacterial concentration and carbonic anhydrase activity were higher when additionally adding ferric ion based on calcium ion; the content of protein, polysaccharides, deoxyribonucleic acid and humic substances in the extracellular polymers also increased compared to control. Calcium ions were biomineralized into calcite and vaterite with multiple morphology. Due to iron doping, the crystallinity and thermal stability of calcium carbonate decreased, the content of OC = O, NC = O and CO-PO increased, the stable carbon isotope values became much more negative, and β-sheet in minerals disappeared. Higher calcium concentrations facilitated ferric ion precipitation, while ferric ions hindered calcium precipitation. The immobilized bacteria performed better in ferric ion removal, with a precipitation ratio exceeding 90%. Free bacteria performed better in calcium removal, and the precipitation ratio reached a maximum of 56%. This research maybe provides some reference for the co-removal of calcium and ferric ions from the oilfield wastewater.
生物矿化因其与传统方法相比显著降低成本而在废水处理领域备受关注。来自油田的回注水中含有极高浓度的钙离子和铁离子，这将对生产造成重大危害。然而，由于嗜盐菌对这种极端条件的耐受性有限，利用生物矿化沉淀这些离子的研究很少。在本研究中，使用游离和固定化的嗜盐菌多德尼希维尔吉芽孢杆菌沉淀这些离子并比较效果，同时进一步探索生物矿化机制和矿物特性。结果表明，在钙离子基础上额外添加铁离子时，细菌浓度和碳酸酐酶活性更高；与对照相比，细胞外聚合物中蛋白质、多糖、脱氧核糖核酸和腐殖质的含量也增加。钙离子被生物矿化为具有多种形态的方解石和球霰石。由于铁掺杂，碳酸钙的结晶度和热稳定性降低，OC = O、NC = O和CO-PO的含量增加，稳定碳同位素值变得更负，矿物中的β-折叠消失。较高的钙浓度促进铁离子沉淀，而铁离子阻碍钙沉淀。固定化细菌在去除铁离子方面表现更好，沉淀率超过90%。游离细菌在去除钙离子方面表现更好，沉淀率最高达到56%。本研究可能为油田废水中钙和铁离子的共去除提供一些参考。
