Biological Processes Laboratory (LPB), São Carlos School of Engineering (EESC), University of São Paulo (USP), Av. João Dagnone, 1100, Santa Angelina, São Carlos, São Paulo 13563-120, Brazil E-mail:
Universidade Federal de Alfenas, Rodovia José Aurélio Vilela, 11999 (BR 267 Km 533) Cidade Universitária, Poços de Caldas, Minas Gerais, Brazil.
Water Sci Technol. 2019 Oct;80(8):1485-1493. doi: 10.2166/wst.2019.398.
Actual acid mine drainage (AMD) containing a high concentration of sulfate (∼1,000 mg·L), dissolved metals, uranium, rare earth elements and yttrium (REY) was treated using a down-flow fixed-structured bed biological reactor (DFSBR). The reactor was operated in a continuous flow mode for 175 days and the temperature was maintained at 30 °C. The synthetic AMD was gradually replaced by the actual AMD in 20, 50 and 75% of the total medium volume. Sugarcane vinasse was used as the electron donor and the influent pH of the reactor was decreased from 6.9 to 4.6 until the system collapsed. REY elements and transition metals were removed from the actual AMD and precipitated in the down-flow fixed-structured bed reactor. Sulfate reduction achieved 67 ± 22% in Phase II and chemical oxygen demand (COD) removal was above 56% in Phases I and II. Removal of La, Ce, Pr, Nd, Sm and Y was higher than 70% in both Phases II and III while Fe, Al, Si and Mn were removed with efficiencies of 79, 67, 48 and 25%, respectively. The results highlighted the potential use of DFSBR in the treatment of AMD, providing possibilities for simultaneous sulfate reduction and metal and REY recovery in a single unit.
采用下流式固定床生物反应器（DFSBR）处理含有高浓度硫酸盐（~1000mg·L）、溶解金属、铀、稀土元素和钇（REY）的实际酸性矿山排水（AMD）。该反应器以连续流模式运行了 175 天，温度保持在 30°C。在 20%、50%和 75%的总介质体积中，逐渐用实际 AMD 替代合成 AMD。甘蔗酒糟被用作电子供体，反应器的进水 pH 值从 6.9 降低到 4.6，直到系统崩溃。实际 AMD 中的 REY 元素和过渡金属被去除并沉淀在 DFSBR 中。在第二阶段，硫酸盐还原达到 67±22%，在第一和第二阶段，化学需氧量（COD）去除率均高于 56%。La、Ce、Pr、Nd、Sm 和 Y 在第二和第三阶段的去除率均高于 70%，而 Fe、Al、Si 和 Mn 的去除率分别为 79%、67%、48%和 25%。结果表明，DFSBR 在 AMD 处理中具有潜在的应用价值，为在单个单元中同时进行硫酸盐还原和金属及 REY 回收提供了可能性。
