College of Architecture and Environment, Sichuan University, Chengdu, 610065, China.
School of Agriculture and Environment, Massey University, Palmerston North, 4442, New Zealand.
Environ Sci Pollut Res Int. 2018 Jun;25(16):15336-15348. doi: 10.1007/s11356-018-1408-5. Epub 2018 Mar 21.
Contamination of soil and water with fluorine (F) leached from phosphogypsum (PG) stacks is a global environmental issue. Millions of tons of PG is produced each year as a by-product of fertilizer manufacture, and in China, weathering is exacerbated by acid rain. In this work, column leaching experiments using simulated acid rain were run to evaluate the mobility of F and the impact of weathering on native bacterial community composition in PG. After a simulated summer rainfall, 2.42-3.05 wt% of the total F content of PG was leached and the F concentration in leachate was above the quality standard for surface water and groundwater in China. Acid rain had no significant effect on the movement of F in PG. A higher concentration of F was observed at the bottom than the top section of PG columns suggesting mobility and reprecipitation of F. Throughout the simulation, the PG was environmentally safe according the TCLP testing. The dominant bacteria in PG were from the Enterococcus and Bacillus genus. Bacterial community composition in PG leached by simulated acid rain (pH 3.03) was more abundant than at pH 6.88. Information on F mobility and bacterial community in PG under conditions of simulated rain is relevant to management of environmental risk in stockpiled PG waste.
氟（F）从磷石膏（PG）堆中淋滤到土壤和水中，造成了全球性的环境问题。每年都有数百万吨 PG 作为肥料制造的副产品产生，而在中国，酸雨加剧了风化作用。在这项工作中，进行了模拟酸雨的柱浸出实验，以评估 F 的迁移性以及风化作用对 PG 中本地细菌群落组成的影响。经过一次模拟夏季降雨后，PG 中总 F 含量的 2.42-3.05wt%被淋滤出，淋出液中的 F 浓度高于中国地表水和地下水的质量标准。酸雨对 PG 中 F 的迁移没有显著影响。PG 柱的底部比顶部观察到更高浓度的 F，这表明 F 的迁移和再沉淀。根据 TCLP 测试，整个模拟过程中 PG 都是环境安全的。PG 中的优势细菌属于肠球菌属和芽孢杆菌属。与 pH 值为 6.88 相比，模拟酸雨（pH 值为 3.03）淋滤的 PG 中的细菌群落组成更为丰富。关于 F 迁移性和 PG 中细菌群落的信息，与储存 PG 废物的环境风险的管理有关。
