Department of Chemical and Environmental Sciences and Material and Surface Science Institute, University of Limerick, National Technological Park, Castletroy, Limerick, Ireland.
Int J Environ Res Public Health. 2010 Sep;7(9):3422-41. doi: 10.3390/ijerph7093422. Epub 2010 Sep 2.
The degradation of sludge solids in an insulated reactor during Autothermal Thermophilic Aerobic Digestion (ATAD) processing results in auto-heating, thermal treatment and total solids reduction, however, the ability to eliminate pathogenic organisms has not been analysed under large scale process conditions. We evaluated the ATAD process over a period of one year in a two stage, full scale Irish ATAD plant established in Killarney and treating mixed primary and secondary sludge, by examining the sludge microbiologically at various stages during and following ATAD processing to determine its ability to eliminate indicator organisms. Salmonella spp. (pathogen) and fecal-coliform (indicator) densities were well below the limits used to validate class A biosolids in the final product. Enteric pathogens present at inlet were deactivated during the ATAD process and were not detected in the final product using both traditional microbial culture and molecular phylogenetic techniques. A high DNase activity was detected in the bulk sludge during the thermophilic digestion stage which may be responsible for the rapid turn over of DNA from lysed cells and the removal of mobile DNA. These results offer assurance for the safe use of ATAD sludge as a soil supplement following processing.
在绝热嗜热好氧消化（ATAD）处理过程中，污泥固体的降解导致自加热、热处理和总固体减少，然而，在大规模处理条件下，尚未分析其消除病原体的能力。我们通过在基尔代尔（Killarney）建立的一个两阶段、全规模的爱尔兰 ATAD 工厂，在一年的时间里评估了 ATAD 工艺，该工厂处理混合的初级和次级污泥，通过在 ATAD 处理过程中和处理后各个阶段对污泥进行微生物学检查，以确定其消除指示生物的能力。沙门氏菌属（病原体）和粪大肠菌群（指示生物）的密度远低于最终产品中用于验证 A 级生物固体的限值。入口处存在的肠道病原体在 ATAD 过程中失活，并且使用传统的微生物培养和分子系统发育技术在最终产品中均未检测到。在嗜热消化阶段，在批量污泥中检测到高 DNA 酶活性，这可能是裂解细胞中 DNA 快速周转和移动 DNA 去除的原因。这些结果为 ATAD 污泥在处理后作为土壤补充剂的安全使用提供了保证。
