Civil and Environmental Engineering Department, University of South Florida, 4202 E. Fowler Ave., Tampa, FL 33620, USA.
J Environ Manage. 2012 Dec 15;112:360-7. doi: 10.1016/j.jenvman.2012.08.014. Epub 2012 Sep 8.
Municipal wastewater treatment has emerged as one of the largest resource consumers in the US. As a result, the goal of municipal wastewater systems has extended from protecting receiving water and human health to improving the system sustainability. This study used the embodied energy and the associated carbon footprint to measure the resource consumption and recovery in wastewater systems. Three resource recovery methods were specifically investigated: onsite energy generation through combined heat and power systems, nutrient recycling through biosolids land application, and water reuse for residential irrigation. The embodied energy and the associated carbon footprint were estimated through an input-output based hybrid energy analysis method and carbon emission factors. A wastewater treatment plant in Tampa, Florida was studied to investigate the possibility of carbon neutrality of wastewater treatment systems. It was shown that the integrated resource (energy, nutrient and water) recovery has the potential to offset all the direct operational energy; however, it is not able to offset the total embodied energy of the treatment plant to achieve carbon neutrality. Among the three resource recovery methods, water reuse has the highest potential of offsetting carbon footprint, while nutrient recycling has the lowest.
城市污水处理已成为美国最大的资源消耗者之一。因此，城市污水处理系统的目标已经从保护受纳水体和人类健康扩展到提高系统的可持续性。本研究使用体现的能量和相关的碳足迹来衡量废水系统中的资源消耗和回收。特别研究了三种资源回收方法：通过热电联产系统进行现场能源发电、通过生物固体土地应用进行营养物质回收以及住宅灌溉用水再利用。通过基于投入产出的混合能源分析方法和碳排放因子来估算体现的能量和相关的碳足迹。以佛罗里达州坦帕市的一家污水处理厂为例，研究了污水处理系统实现碳中和的可能性。结果表明，综合资源（能源、营养物质和水）回收有可能抵消所有直接运行能源；然而，它无法抵消处理厂的总体现能量，以实现碳中和。在这三种资源回收方法中，水再利用具有最大的碳足迹抵消潜力，而营养物质回收的潜力最小。
