Department of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China; Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Beijing 100083, China.
Department of Coal and Syngas Conversion, Sinopec Research Institute of Petroleum Processing, Beijing 100083, China.
Sci Total Environ. 2021 Jul 1;776:145596. doi: 10.1016/j.scitotenv.2021.145596. Epub 2021 Feb 4.
Hydrothermal liquefaction (HTL) is a promising thermochemical technology for the treatment of hazardous wastes such as penicillin residue (PR). For the treatment of aqueous waste produced by PR in the HTL process, aqueous phase circulation is an attractive solution, both environmentally and economically. The present study shows that aqueous phase circulation can promote the transfer of organic matter from the aqueous phase to bio-oil. The content of organic acids and alcohols in the aqueous phase decreased significantly, and the bio-oil yield and energy recovery efficiency also increased. Under non-catalytic conditions, the bio-oil yield increased from 26.09 wt% to 33.72 wt%. The use of NaCO as a catalyst further improved the bio-oil yield. After a single aqueous phase circulation, the bio-oil yield increased to 34.63 wt%, and the energy recovery efficiency increased to 66.94%. Under catalytic hydrothermal conditions, the content of organic acids in the bio-oil was reduced using aqueous phase circulations, which improved the quality of the bio-oil. At the same time, the NaCO catalyst promoted the hydrolysis of PR to form small molecule organic matter, inhibited the formation of coke, and reduced the content of carbon, hydrogen and oxygen in the solid residue. An increase of cycle times led to excessive accumulation of NaCO, which had a negative impact on the yield of bio-oil. Nitrogen-containing compounds in the bio-oil increased to a certain extent, which renders it necessary to consider denitrification treatments in the future. The work provides a useful reference for further research on the preparation of high quality bio-oil by PR hydrothermal liquefaction.
水热液化 (HTL) 是一种有前途的热化学技术，可用于处理青霉素残留物 (PR) 等危险废物。对于 PR 在 HTL 过程中产生的废水，水相循环是一种在环境和经济方面都具有吸引力的解决方案。本研究表明，水相循环可以促进有机物从水相向生物油的转移。水相中有机酸和醇的含量显著降低，生物油产率和能量回收效率也有所提高。在非催化条件下，生物油产率从 26.09 wt%增加到 33.72 wt%。使用 NaCO 作为催化剂进一步提高了生物油产率。经过单次水相循环，生物油产率增加到 34.63 wt%，能量回收效率增加到 66.94%。在催化水热条件下，通过水相循环降低了生物油中的有机酸含量，从而提高了生物油的质量。同时，NaCO 催化剂促进了 PR 的水解形成小分子有机物，抑制了焦炭的形成，降低了固体残渣中碳、氢和氧的含量。循环次数的增加导致 NaCO 过度积累，这对生物油的产率产生了负面影响。生物油中的含氮化合物增加到一定程度，这使得在未来有必要考虑进行脱硝处理。这项工作为进一步研究通过 PR 水热液化制备高质量生物油提供了有益的参考。
