Department of Environmental Engineering, Yonsei University, 1, Yeonsedae-gil, Wonju, Republic of Korea.
Department of Environmental Engineering, Yonsei University, 1, Yeonsedae-gil, Wonju, Republic of Korea.
J Hazard Mater. 2020 Feb 15;384:121291. doi: 10.1016/j.jhazmat.2019.121291. Epub 2019 Sep 25.
The need for appropriate management of mercury (Hg) wastes is increasing for active implementation of the Minamata Convention on Mercury. Though Hg can be a contaminant if it is not dealt with properly, recovered Hg can become a resource. Besides, a recovered Hg with reduced volume can be managed efficiently. This study examined the effect of NaOH for the recovery of elemental Hg from a waste sludge from an industrial process using the thermal desorption and condensation. For this purpose, the operating conditions, including temperature and pressure of the apparatus, were derived based on the experiments using Hg compounds (HgS and HgO), simulated waste (mixtures of HgCl/AsO and HgS/AsO). The reduced chamber pressure promoted to the recovery of elemental Hg via the thermal desorption. NaOH was introduced to increase the recovery efficiency of Hg in the presence of interfering substances such as S and As compounds. The Hg recovery efficiency increased, and 62.5% of Hg was recovered as elemental form by adding NaOH via thermal desorption and gas condensation with a lab-scale apparatus. Interfering substances such as Cl, S, and As compounds were captured in the bottom ash when bound with Na.
随着《汞水俣公约》的积极实施，对汞（Hg）废物进行适当管理的需求日益增加。尽管 Hg 如果处理不当可能成为污染物，但回收的 Hg 可以成为一种资源。此外，体积减小的回收 Hg 可以更有效地进行管理。本研究考察了在热解吸和冷凝过程中使用 NaOH 从工业过程废物污泥中回收元素 Hg 的效果。为此，根据使用 Hg 化合物（HgS 和 HgO）、模拟废物（HgCl/AsO 和 HgS/AsO 的混合物）进行的实验，得出了包括设备温度和压力在内的操作条件。降低腔室压力可通过热解吸促进元素 Hg 的回收。在存在 S 和 As 化合物等干扰物质的情况下，加入 NaOH 可提高 Hg 的回收效率。通过使用实验室规模设备进行热解吸和气体冷凝，添加 NaOH 可提高 Hg 回收率，其中 62.5%以元素形式回收。当与 Na 结合时，Cl、S 和 As 等干扰物质会被捕获到底部灰烬中。
