With increasing energy and resource consumption due to population growth, the biorefinery concept is becoming popular. This concept aims to harness all the properties of biomass by producing energy and recovering useful chemical products. Nutrients such as nitrogen and phosphorus play a key role in the world’s food production because they are the main elements used in fertilizer production. Hydrothermal carbonization (HTC) has been presented as a suitable option for energy recovery that can also be used as a pre-treatment for enhanced nutrient recovery. During the HTC process, part of the nitrogen and phosphorus are solubilized into the process water and the other part remains within the hydrochar. Hydrochars are mainly used as soil amendments due to their high content of phosphorus and nitrogen, but in this process, water still contains a considerable concentration of these compounds making it a potential source for their recovery. Therefore, HTC may boost the nutrient recovery strategy by extraction (process water) or densification (hydrochar) from biomass if it is coupled with another nutrient recovery process. This review presents an overview of the phosphorus and nitrogen fate during the HTC process from a perspective of nutrient recovery, presenting existing technologies and future trends.

随着人口增长带来的能源和资源消耗的增加，生物炼制概念变得越来越流行。该概念旨在通过产生能量和回收有用的化学产品来利用生物质的所有特性。营养素（例如氮和磷）在世界食品生产中起着关键作用，因为它们是肥料生产中使用的主要元素。水热碳化（HTC）已被提出作为能量回收的合适选择，也可以用作增强营养物回收的预处理。在HTC过程中，一部分氮和磷被溶解到生产用水中，而另一部分则保留在烃中。碳氢化合物因其磷和氮含量高而主要用作土壤改良剂，但在此过程中，水中仍然含有相当浓度的这些化合物，使其成为回收的潜在来源。因此，如果将HTC与另一种营养素回收过程结合使用，则HTC可以通过从生物质中提取（工艺用水）或致密化（氢炭）来提高营养素回收策略。这篇综述从养分回收的角度概述了HTC过程中磷和氮的命运，并介绍了现有技术和未来趋势。