Department of Chemical Engineering and National Centre for Combustion Research and Development, Indian Institute of Technology Madras, Chennai 600036, India.
Department of Chemical Engineering and National Centre for Combustion Research and Development, Indian Institute of Technology Madras, Chennai 600036, India.
Bioresour Technol. 2021 Dec;342:125951. doi: 10.1016/j.biortech.2021.125951. Epub 2021 Sep 15.
Aqueous phase (AP) recirculation is a promising process intensification strategy to improve the yield and quality of the products and cost efficiency of the hydrothermal liquefaction (HTL) process by replacing the fresh water used in the experiments. The results demonstrate that AP recirculation in the HTL of rice straw decreases the bio-crude yield from 32.6 wt% to 9.1 wt% after the third recycle, while enhancing the bio-char yield up to 64.1 wt%. The bio-crude and bio-char show improved carbon and hydrogen content with AP recirculation. The decrease in selectivity to aliphatic hydrocarbons in the bio-crude and bio-char, coupled with increase in H content in the gaseous phase, suggests the prevalence of dehydrogenation reactions. The bio-char achieved better thermal stability, water retention and cation exchange capacity with AP recirculation. There was a significant accumulation of K, Ca and Cl with a concomitant decrease in silicates, sulfate and phosphate in the AP.
水相（AP）再循环是一种很有前途的强化工艺策略，可以通过取代实验中使用的淡水来提高水热液化（HTL）过程的产品收率和质量、以及成本效率。结果表明，稻草 HTL 中的 AP 再循环在第三次循环后将生物粗油产率从 32.6wt%降低至 9.1wt%，同时将生物炭产率提高至 64.1wt%。生物粗油和生物炭的碳和氢含量随着 AP 再循环而增加。生物粗油和生物炭中脂肪族烃的选择性降低，同时气态相中 H 含量增加，表明脱氢反应普遍存在。AP 再循环使生物炭具有更好的热稳定性、保水性和阳离子交换能力。AP 中 K、Ca 和 Cl 的积累显著，而硅酸盐、硫酸盐和磷酸盐的含量相应减少。
