Department of Environment Safety System Engineering, Semyung University, 65 Semyung-ro, Jecheon-si 27136, Korea.
Department of Biological & Environmental Engineering, Semyung University, 65 Semyung-ro, Jecheon-si 27136, Korea.
Int J Environ Res Public Health. 2022 Feb 4;19(3):1775. doi: 10.3390/ijerph19031775.
Fluorine (F) enrichment originating from natural sources is difficult to remove using chemical washing methods due to the large chemical-resistant residual fraction. This study evaluates the feasibility of using a froth-flotation separation method to remediate soil with a high F concentration caused by mica weathering, and it investigates the optimal conditions for this process, including pH of the slurry, collector dosage, and sample mechanical preparation strategy. The established optimum conditions are pH 3.5, 300 mg/kg collector dosage (tallow amine acetate), which can effectively separate quartz and mica, and a sieving-and-milling strategy that involves discarding particles of size < 0.05 mm, milling those in the range of 0.5-2.0 mm (until < approx. 0.3 mm), and mixing particles with sizes in the range of 0.05-0.5 mm. The target contamination level of 400 mg/kg for the test soil was not met after the first flotation separation process. However, after milling the residue of the first process and subjecting it to a second flotation separation process, the required contamination level was achieved. Consequently, the proposed froth-flotation separation process can be used as a successful alternative technique to remediate F-enriched soils from natural origin that have highly chemical-resistant forms.
氟（F）的天然来源富集物很难通过化学洗涤方法去除，因为其中存在大量抗化学试剂的残留部分。本研究评估了使用泡沫浮选分离方法来修复云母风化导致高氟浓度土壤的可行性，并研究了该过程的最佳条件，包括浆液 pH 值、捕收剂用量和样品机械制备策略。确定的最佳条件为 pH 值 3.5，捕收剂用量 300mg/kg（牛脂胺乙酸盐），这可以有效地分离石英和云母，以及一种筛选和研磨策略，即丢弃粒径<0.05mm 的颗粒，研磨 0.5-2.0mm 范围内的颗粒（直至<约 0.3mm），并混合粒径在 0.05-0.5mm 范围内的颗粒。对于试验土壤，目标污染水平为 400mg/kg，但第一次浮选分离后未达到。然而，将第一次过程的残留物研磨并进行第二次浮选分离后，达到了所需的污染水平。因此，所提出的泡沫浮选分离工艺可以作为一种成功的替代技术，用于修复具有高抗化学试剂形式的天然来源富氟土壤。
