Temperature phased anaerobic digestion with side-stream archaea enrichment for Lulu Island wastewater treatment plant digester upgrade

污水处理厂（WWTPs）的废污泥处理是主要挑战之一，其成本往往超过液体流的处理和排放。在几种污泥处理方案中，厌氧消化（AD）已被证明是一种有效的技术。AD本质上是一种生物反应器，诱导微生物形成挥发性脂肪酸和甲烷，通过引入污水污泥或粪便等有机物来提供。除了产生甲烷（可转化为热能/电能）外，AD的其他好处还包括转移垃圾填埋场的有机废物、减少固体、病原体、生产有机肥以及减少温室气体排放。露露岛污水处理厂（不列颠哥伦比亚省里士满）一直在并行运行两个单级AD。虽然该工艺实现了63%的固体减少，但当其中一个蒸煮器需要关闭进行维护/维修时，目前的配置不能提供过程冗余。此外，脱水消化物符合B类生物固体的条件，对土地应用有限制。为了降低操作风险和加强资源回收，大温哥华地区有兴趣在其污水处理厂开发下一代AD技术。在这个项目中，提出了一个带有侧流生物增强器的双级AD串联，作为一种先进的AD选择，可以提高固体还原率，将沼气组成从典型的60%提高到90%或更高，提高消化液的脱水能力，并将生物固体从B类提升到a类。该项目还将包括微生物分析，结合选择的多组学（DNA和RNA）分析，以深入了解群落结构。活动和功能在常规和高级AD配置。大温哥华地区已预算100万美元用于在露露岛水资源回收设施整合和运行一个试点规模的AD，并预算1300万美元用于工厂升级，以向电网提供沼气。从该项目中获得的实验室规模的结果将为中试工厂的设计/建造/运营提供明确的方向，这将使先进的AD工艺“离线”评估成为可能，而不会危及正在进行的运营。

Waste sludge processing at wastewater treatment plants (WWTPs) represents one of the major challenges, often costing more than the treatment and discharge of the liquid stream. Among several waste sludge treatment options, anaerobic digestion (AD) has proven to be an effective technology. AD is essentially a bioreactor that induces microorganisms to form volatile fatty acids and methane, supplied through the introduction of organic matter such as sewage sludge or manure. In addition to generating methane (which can be converted to heat/electricity), the other benefits of AD are the diversion of organic waste from landfills, reduction of solids, pathogens, production of organic fertilizer as well as reduction of GHG emissions. Lulu Island WWTP (Richmond, BC) has been operating two single-stage AD in parallel. Although the process achieves 63% solids reduction, the current configuration does not provide process redundancy when one of the digesters needs to be shut down for maintenance/repair. Moreover, the dewatered digestate qualifies as Class B biosolids with restrictions for land application. For reducing operational risks and intensifying resource recovery, Metro Vancouver is interested in developing next generation AD technologies at their WWTPs. In this project, a dual-stage AD tandem with a side-stream bioaugmentor is proposed as an advanced AD option for increasing solids reduction, upgrading biogas methane composition from the typical 60% to 90% or higher, enhancing digestate dewaterability, and upgrading biosolids from Class B to Class A. The project will also include microbial profiling combined with select multi-omic (DNA and RNA) analyses to gain insight to community structure, activity and function in both conventional and advanced AD configurations. Metro Vancouver has budgeted $1M to integrate and operationalize a pilot-scale AD at Lulu Island Water Resource Recovery Facility and $13M for a plant upgrade to feed biogas into the power grid. Lab-scale results obtained from this project will provide clear direction for the pilot-plant design/built/operation, which will enable the evaluation of advanced AD processes "offline" without risking ongoing operations.