National University of Ireland, Galway, H91 TK33 Galway, Ireland.
National University of Ireland, Galway, H91 TK33 Galway, Ireland.
J Hazard Mater. 2023 Oct 5;459:132134. doi: 10.1016/j.jhazmat.2023.132134. Epub 2023 Jul 23.
The use of phytoremediation as a method for wastewater treatment or removal of pollutants is garnering significant interest and duckweed (DW), a free floating macrophyte, depicts significant potential for the removal of nutrients and toxic compounds from contaminated waters. The present work aimed to develop an integrated process for remediating selenate (Se(VI)) using DW biomass and subsequent use of Se(VI) enriched DW for biogas production. The main objective is to extend the application of selenium (Se) enriched DW biomass for biogas production. Se(VI) enriched DW biomass (Se-DW) gave higher methane production (48.38 ± 3.6 mL gCOD) than control DW biomass (C-DW) (24.46 ± 3.6 mL gCOD). To further enhance methane production, three pre-treatment approaches (acid, alkali and hydrothermal) were assessed and the solid and liquid fractions obtained after pre-treatment were used as a substrate. Pre-treatments increased biogas production in both Se-DW and C-DW than untreated conditions. Liquid fractions gave higher biogas production than solid fractions. In Se-DW, highest biogas production was observed in hydrothermal pre-treated Se-DW, while in C-DW, acid pre-treatment gave higher biogas production. Methane production was shown to be enhanced up to a Se(VI) concentration of 1.7 mg L, whereas a concentration beyond this lowered biogas production.
利用植物修复作为废水处理或去除污染物的方法正引起人们的极大关注，浮萍（DW）作为一种自由漂浮的大型水生植物，具有从受污染的水中去除营养物质和有毒化合物的巨大潜力。本研究旨在开发一种利用 DW 生物质修复硒酸盐（Se(VI)）的综合工艺，以及随后利用富含 Se(VI)的 DW 进行沼气生产。主要目的是扩展富含硒（Se）的 DW 生物质在沼气生产中的应用。与对照 DW 生物质（C-DW）（24.46 ± 3.6 mL gCOD）相比，富含 Se(VI)的 DW 生物质（Se-DW）的甲烷产量更高（48.38 ± 3.6 mL gCOD）。为了进一步提高甲烷产量，评估了三种预处理方法（酸、碱和水热），并将预处理后获得的固液两部分用作底物。预处理提高了 Se-DW 和 C-DW 的沼气产量，高于未处理的条件。液体部分比固体部分产生更高的沼气产量。在 Se-DW 中，在经过水热预处理的 Se-DW 中观察到最高的沼气产量，而在 C-DW 中，酸预处理产生了更高的沼气产量。甲烷产量在 Se(VI)浓度达到 1.7 mg L 时得到增强，而超过该浓度会降低沼气产量。
