Research Institute on Mines and Environment (RIME), University of Québec in Abitibi-Témiscamingue (UQAT), Rouyn-Noranda, QC, Canada.
Sci Total Environ. 2023 Sep 15;891:164279. doi: 10.1016/j.scitotenv.2023.164279. Epub 2023 May 19.
Treatment of ammonia nitrogen (NH-N) in mine effluents generates N-rich residual materials, such as moving bed biofilm reactor (MBBR) biomass and spent zeolite. Using them as substitutes for mineral fertilizers in revegetation of mine tailings avoids disposal and contributes to a circular economy. The study evaluated the effect of MBBR biomass and N-rich zeolite amendments on above- and below-ground growth and foliar nutrient and trace element concentrations of a legume and several graminoid species grown on non-acid generating gold mine tailings. N-rich zeolite (clinoptilolite) was produced by treating saline (up to 60 mS/cm) synthetic and real mine effluents (250 vs 280 mg/L NH-N). A three-month pot experiment was conducted with a dose of tested amendments equivalent to 100 kg/ha N and compared to unamended tailings (as negative control), tailings with a mineral NPK fertilizer, and a topsoil (as positive controls). Higher foliar N concentrations were found in amended and fertilized tailings vs negative control, but N was less available in the zeolite treatments than in other tailings treatments. For all plant species, the mean leaf area and above-ground, root, and total biomasses were similar in the zeolite-amended tailings to the unamended tailings, while the MBBR biomass amendment resulted in similar above- and below-ground growth to the NPK fertilized tailings and the commercial topsoil. Trace metal concentrations in water leaching from the amended tailings remained low, but tailings amended with zeolite exported NO-N concentrations up to 10 times greater (>200 mg/L) after 28 days compared to all other treatments. Foliar Na concentrations in zeolite mixtures were six to nine times higher than in other treatments. The MBBR biomass is a promising potential amendment for revegetation of mine tailings. However, Se concentrations in plants after MBBR biomass amendment should not be underestimated, while Cr transfer from tailings to plants was observed.
处理矿废水中的氨氮（NH-N）会产生富含氮的剩余物质，如移动床生物膜反应器（MBBR）生物量和废沸石。将其用作矿山尾矿植被恢复的矿物肥料替代品，避免了处置，并有助于循环经济。本研究评估了 MBBR 生物量和富含氮的沸石改良剂对在非酸性产生金矿尾矿上生长的豆科和几种禾本科物种地上和地下生长以及叶片养分和痕量元素浓度的影响。富含氮的沸石（斜发沸石）是通过处理含盐量（高达 60 mS/cm）的合成和真实矿废水（250 与 280 mg/L NH-N）来生产的。进行了为期三个月的盆栽试验，测试的改良剂剂量相当于 100 kg/ha N，并与未改良的尾矿（作为负对照）、含有矿物 NPK 肥料的尾矿和表土（作为正对照）进行了比较。与负对照相比，改良和施肥的尾矿中叶片的氮浓度较高，但沸石处理中的氮不如其他尾矿处理中的氮有效。对于所有植物物种，在沸石改良的尾矿中，叶片面积和地上、根和总生物量与未改良的尾矿相似，而 MBBR 生物量改良剂的地上和地下生长与 NPK 施肥的尾矿和商业表土相似。从改良尾矿中浸出的水中痕量金属浓度仍然较低，但与所有其他处理相比，用沸石改良的尾矿在 28 天后排出的硝态氮浓度高出 10 倍以上（>200 mg/L）。沸石混合物中叶片的 Na 浓度比其他处理高 6 到 9 倍。MBBR 生物量是矿山尾矿植被恢复的一种很有前景的潜在改良剂。然而，不应低估 MBBR 生物量改良后植物中的 Se 浓度，同时观察到 Cr 从尾矿向植物转移。
