Civil, Environmental, and Architectural Engineering Department, The University of Kansas, Lawrence, KS, 66045, USA.
Chemical & Petroleum Engineering Department, The University of Kansas, Lawrence, KS, 66045, USA.
Chemosphere. 2020 Jan;238:124573. doi: 10.1016/j.chemosphere.2019.124573. Epub 2019 Aug 12.
This study investigated the nutrient content and reuse potential of wastewater generated during hydrothermal liquefaction of microalgal biomass. The hydrothermal liquefaction reaction was tested at 270, 300, 330, and 345 °C to determine the effect of temperature on the formation of non-biodegradable dissolved organic nitrogen (nbDON). Total nitrogen, ammonium, color, and toxicity were selected as key characteristics for the reuse of hydrothermal liquefaction wastewater. Results indicated that a higher concentration of nbDON (nbDON defined with a 5 day growth assay) and more diverse heterocyclic N-containing organic compounds were associated with greater toxicity as measured by a growth rate assay. For the tested temperature ranges, the total nitrogen content of the hydrothermal liquefaction wastewater slightly decreased from 5020 ± 690 mg L to 4160 ± 120 mg L, but the % nbDON fraction increased from 57 ± 3 %DON to 96 ± 5 %DON. The temperature of hydrothermal liquefaction reactions can be optimized to maximize carbon conversion and nitrogen recovery.
本研究考察了水热液化微藻生物质过程中产生的废水的营养成分和再利用潜力。在 270、300、330 和 345°C 下测试了水热液化反应，以确定温度对不可生物降解溶解有机氮（nbDON）形成的影响。总氮、氨、颜色和毒性被选为水热液化废水再利用的关键特性。结果表明，较高浓度的 nbDON（用 5 天生长测定法定义的 nbDON）和更多种类的含杂环 N 的有机化合物与更高的毒性相关，这可以通过生长速率测定法来衡量。在所测试的温度范围内，水热液化废水中的总氮含量从 5020±690mg/L 略有下降到 4160±120mg/L，但 nbDON 分数从 57±3%DON 增加到 96±5%DON。水热液化反应的温度可以优化以最大程度地提高碳转化率和氮回收。
