Anaerobic digestion (AD) for waste, and wastewater, management was identified in the 1970s as a forerunner in the push for sustainability. The development of AD applications resulted in the discovery of “anaerobic granules,” which are multitrophic bio-aggregates comprising methanogenic consortia capable of digesting waste organics to methane-rich biogas suitable for use as a renewable bioenergy. In the intervening years the emergence of the anaerobic ammonium oxidizing (anammox) granule, aerobic granule, hydrogenic granule, oxygenic photogranule, and many other functionally-specialized granules, has opened new opportunities in wastewater treatment, and resource-recovery, biotechnology. As a single entity, a granule represents an entire community of microorganisms. This review compares three of the most influential types: the anaerobic (methanogenic), aerobic and anammox granule. The main characteristics, biochemical processes, and typical makeup of the microbial community in each type are discussed. Finally, the adoption of granules as an intriguing “playground” for experiments in microbial ecology is reviewed.

废物和废水的厌氧消化（AD）管理在1970年代被确定为推动可持续发展的先驱。AD应用的发展导致发现了“厌氧颗粒”，这是一种多营养生物聚集体，包括能够将废有机物消化成适合用作可再生生物能源的富含甲烷的沼气的产甲烷菌团。在随后的几年中，厌氧铵氧化（厌氧氨）颗粒，好氧颗粒，氢颗粒，氧光颗粒和许多其他功能特殊的颗粒的出现为废水处理和资源回收，生物技术打开了新的机会。作为单个实体，颗粒代表整个微生物群落。这篇评论比较了三种最具影响力的类型：厌氧（产甲烷），好氧和厌氧菌颗粒。讨论了每种类型的微生物群落的主要特征，生化过程和典型组成。最后，对颗粒作为微生物生态学实验中一个有趣的“游乐场”的采用进行了综述。