Wang Zhiyao, Lu Xi, Zheng Min, Hu Zhetai, Batstone Damien, Yuan Zhiguo, Hu Shihu
Australian Centre for Water and Environmental Biotechnology (ACWEB, formerly AWMC) The University of Queensland St. Lucia Queensland 4072 Australia.
Water Research Centre, School of Civil and Environmental Engineering, University of New South Wales, Sydney, New South Wales 2052, Australia.
Water Res X. 2024 Jul 23;24:100240. doi: 10.1016/j.wroa.2024.100240. eCollection 2024 Sep 1.
Wastewater treatment plants produce large amounts of sludge requiring stabilization before safe disposal. Traditional biological stabilization approaches are cost-effective but generally require either an extended retention time (10-40 days), or elevated temperatures (40-80 °C) for effective pathogens inactivation. This study overcomes these limitations via a novel acidic aerobic digestion process, leveraging an acid-tolerant ammonia-oxidizing bacterium (AOB) Nitrosoglobus. To retain this novel but slowly growing AOB, we proposed the first-ever application of a classical wastewater configuration-moving bed biofilm reactor (MBBR)-for sludge treatment. The AOB in biofilm maintains acidic pH and high nitrite levels in sludge, generating free nitrous acid in situ to expedite sludge stabilization. This process was tested in two laboratory-scale aerobic digesters processing full-scale anaerobically digested sludge. At an ambient temperature of 20 °C, pathogens were reduced to levels well below the threshold specified for the highest stabilization level (Class A), within a retention time of 3.5 days. A high volatile solids reduction of 27.4 ± 5.2% was achieved. Through drastically accelerating stabilization and enhancing reduction, this process substantially saves capital and operational costs for sludge disposal.
污水处理厂会产生大量污泥，在安全处置前需要进行稳定化处理。传统的生物稳定化方法具有成本效益，但通常需要较长的停留时间（10 - 40天），或者较高的温度（40 - 80°C）才能有效灭活病原体。本研究通过一种新型酸性好氧消化工艺克服了这些局限性，该工艺利用了一种耐酸氨氧化细菌（AOB）——亚硝酸oglobus。为了保留这种新型但生长缓慢的AOB，我们首次提出将经典的废水处理装置——移动床生物膜反应器（MBBR）应用于污泥处理。生物膜中的AOB维持污泥中的酸性pH值和高亚硝酸盐水平，原位生成游离亚硝酸以加速污泥稳定化。该工艺在两个处理全尺寸厌氧消化污泥的实验室规模好氧消化器中进行了测试。在20°C的环境温度下，病原体在3.5天的停留时间内被降低到远低于最高稳定化水平（A类）规定阈值的水平。实现了27.4±5.2%的高挥发性固体减少率。通过大幅加速稳定化和增强减少率，该工艺大大节省了污泥处置的资本和运营成本。
