College of Civil Engineering, Nanjing Forestry University, Nanjing, 210037, China.
Environ Sci Pollut Res Int. 2021 Mar;28(11):13829-13841. doi: 10.1007/s11356-020-11652-9. Epub 2020 Nov 16.
Advanced processing of low C/N sewage faces the carbon sources shortage, while quantities of agricultural biomass wastes need to be disposed. This study investigated the potential of quantitative modified biomass addition in constructed wetlands (CWs) filled with polyethylene fillers. Results showed that the lignin in NaOH-heating pretreated corn stalks (NH-CSs) was destroyed, and the wrinkles on the stalks increased and became more soft after pretreatment, which was more conducive to the utilization of carbon sources and attachment of microorganisms. Compared with glucose and sodium acetate, the denitrification with mixed carbon source (glucose and NH-CSs) had the highest effective utilization percentage (61.37%) and NH-CSs were expected to become stable and fast-release carbon sources. After adding 30 g NH-CSs to the rear unit of CW with polyethylene fillers (CW-A), TN removal efficiency was increased by 18.21%, and the average removal efficiency of COD, NH-N, TN, and TP reached 54.83%, 89.95%, 64.11%, and 45.04%, respectively. Compared with the traditional CW (CW-B), CW-A had a significant denitrification advantage (P < 0.05), but the removal efficiency and effluent stability of phosphorus were inferior to CW-B. These results indicate that the biomass carbon sources such as corn stalks and polyethylene fillers have a good potential to improve the denitrification in CWs.
高级处理低 C/N 污水面临碳源短缺，而大量农业生物质废物需要处理。本研究调查了定量改性生物质添加到填充聚乙烯填料的人工湿地 (CW) 中的潜力。结果表明，NaOH 加热预处理玉米秸秆（NH-CSs）中的木质素被破坏，预处理后秸秆的皱纹增加且变得更加柔软，这更有利于碳源的利用和微生物的附着。与葡萄糖和乙酸钠相比，混合碳源（葡萄糖和 NH-CSs）的反硝化具有最高的有效利用率（61.37%），NH-CSs 有望成为稳定且快速释放的碳源。在聚乙烯填料 CW（CW-A）的后单元中添加 30 g NH-CSs 后，TN 去除效率提高了 18.21%，COD、NH-N、TN 和 TP 的平均去除效率分别达到 54.83%、89.95%、64.11%和 45.04%。与传统 CW（CW-B）相比，CW-A 具有显著的脱氮优势（P<0.05），但磷的去除效率和出水稳定性逊于 CW-B。这些结果表明，玉米秸秆和聚乙烯填料等生物质碳源具有改善 CW 中脱氮的良好潜力。
