Lignocellulosic biomass is a promising alternative to petroleum oil for producing energy and chemicals, owing to its abundance and sustainability. In the past decades, extensive research has applied a wide range of thermo-chemical technologies for converting biomass into value-added products. Among them, hydrothermal liquefaction (HTL) is regarded to be one of the most effective techniques to produce bio-fuels and bio-based chemicals. However, there are still several technical barriers that must be addressed before the industrialization of HTL technology. Although many previous reviews have summarized the reaction mechanism, properties of liquefaction products, and various operating parameters, few articles have discussed the potential applications of HTL products and the techno-economic problems facing by the industrialization of HTL. Therefore, in this review, the possible applications of HTL products (bio-crude, aqueous phase, solid residue, and gas) were thoroughly discussed. In addition, the current challenges of HTL treatment, especially for the continuous operation, to produce bio-based fuel and chemicals is reviewed. Finally, the possible future directions and the main conclusions are covered.

木质纤维素生物质由于其丰富性和可持续性，是石油生产能源和化学品的有前途的替代品。在过去的几十年中，广泛的研究应用了广泛的热化学技术将生物质转化为增值产品。其中，水热液化（HTL）被认为是生产生物燃料和生物基化学品的最有效技术之一。但是，在HTL技术产业化之前，仍然必须解决几个技术障碍。尽管以前的许多评论都概述了反应机理，液化产物的性质和各种操作参数，但很少有文章讨论了HTL产品的潜在应用以及HTL工业化所面临的技术经济问题。因此，在这篇综述中，彻底讨论了HTL产品（生物原油，水相，固体残留物和气体）的可能应用。此外，本文还回顾了HTL处理当前的挑战，特别是对于连续操作生产生物基燃料和化学品的挑战。最后，涵盖了可能的未来方向和主要结论。