Department of Water Technology and Environmental Engineering, Faculty of Environmental Protection, Institute of Chemical Technology Prague, Czech Republic.
Water Sci Technol. 2012;66(6):1277-81. doi: 10.2166/wst.2012.317.
Anaerobic digestion is the only energy-positive technology widely used in wastewater treatment. Full-scale data prove that the anaerobic digestion of sewage sludge can produce biogas that covers a substantial amount of the energy consumption of a wastewater treatment plant (WWTP). In this paper, we discuss possibilities for improving the digestion efficiency and biogas production from sewage sludge. Typical specific energy consumptions of municipal WWTPs per population equivalent are compared with the potential specific production of biogas to find the required/optimal digestion efficiency. Examples of technological measures to achieve such efficiency are presented. Our findings show that even a municipal WWTP with secondary biological treatment located in a moderate climate can come close to energy self-sufficiency. However, they also show that such self-sufficiency is dependent on: (i) the strict optimization of the total energy consumption of the plant, and (ii) an increase in the specific biogas production from sewage sludge to values around 600 L per kg of supplied volatile solids.
厌氧消化是唯一广泛应用于污水处理的能量正增长技术。大规模数据证明，污水污泥的厌氧消化可以产生沼气，沼气可以覆盖污水处理厂（WWTP）的大量能源消耗。本文讨论了提高污水污泥消化效率和沼气产量的可能性。将典型的人均市政 WWTP 的单位能耗与沼气的潜在特定产量进行比较，以找到所需/最佳的消化效率。介绍了实现这种效率的技术措施示例。我们的研究结果表明，即使是位于中等气候条件下的具有二级生物处理的市政 WWTP，也可以接近能源自给自足。然而，它们也表明这种自给自足取决于：（i）严格优化工厂的总能源消耗，以及（ii）将污水污泥的单位沼气产量提高到每供应挥发性固体 600 升左右的值。
