High-solid anaerobic digestion (HS-AD) has been applied extensively during the last few decades for treating various organic wastes, such as agricultural wastes, organic fractions of municipal solid wastes, and kitchen wastes. However, the application of HS-AD to the processing of sewage sludge (SS) remains limited, which is largely attributable to its poor process stability and performance. Extensive research has been conducted to attempt to surmount these limitations. In this review, the main factors affecting process stability and performance in the HS-AD of SS are comprehensively reviewed, and the improved methods in current use, such as HS sludge pre-treatment and anaerobic co-digestion with other organic wastes, are summarised. Besides, this paper also discusses the characteristics of substance transformation in the HS-AD of SS with and without thermal pre-treatment. Research has shown that the HS effect is due to the presence of high concentrations of substances that may inhibit the function of anaerobic microorganisms, and that it also results in poor mass transfer, a low diffusion coefficient, and high viscosity. Finally, knowledge gaps in the current research on HS-AD of SS are identified. Based on these, it proposes that future efforts should be devoted to standardising the definition of HS sludge, revealing the law of migration and transformation of pollutants, describing the metabolic pathways by which specific substances are degraded, and establishing accurate mathematical models. Moreover, developing green sludge dewatering agents, obtaining high value-added products, and revealing effects of the above two on HS-AD of SS can also be considered in future.

在过去的几十年中，高固体厌氧消化（HS-AD）已广泛用于处理各种有机废物，例如农业废物，市政固体废物的有机部分和厨房废物。但是，HS-AD在污水污泥（SS）处理中的应用仍然受到限制，这在很大程度上归因于其工艺稳定性和性能较差。为了克服这些限制，已经进行了广泛的研究。本文综述了影响SS的HS-AD的工艺稳定性和性能的主要因素，并总结了目前使用的改进方法，例如HS污泥的预处理以及与其他有机废物的厌氧共消化。 。除了，本文还讨论了在有和没有热预处理的情况下，SS的HS-AD中物质转化的特征。研究表明，HS效应是由于可能抑制厌氧微生物功能的高浓度物质的存在，并且还导致质量传递不良，扩散系数低和粘度高。最后，确定了当前有关SS的HS-AD研究的知识差距。在此基础上，建议未来应致力于标准化HS污泥的定义，揭示污染物的迁移和转化规律，描述降解特定物质的代谢途径以及建立准确的数学模型。此外，开发绿色污泥脱水剂，获得高附加值的产品，