Local and downstream impacts of water reuse at power plants

reclaimed water;thermoelectric power plants

Barker, Zachary Alan ; Stillwell ; Ashlynn S.

关键词: reclaimed water;    thermoelectric power plants;   

Others  :  https://www.ideals.illinois.edu/bitstream/handle/2142/88999/BARKER-THESIS-2015.pdf?sequence=1&isAllowed=y

美国|英语

来源: The Illinois Digital Environment for Access to Learning and Scholarship

【 摘 要 】

Reclaimed water, treated effluent from a municipal wastewater treatment plant, is a viable resource for mitigating growing stress on water resources. One such application of reclaimed water is cooling thermoelectric power plants. Using reclaimed water along with recirculating cooling towers has a variety of benefits such as making use of an otherwise low-value waste stream and providing a reliable water source. However, consumption of water that would otherwise be returned to a surface waterway might cause negative impacts to downstream locations. This work presents a method that utilizes quantifiable metrics to assess the implications of constructing a consumptive water reuse system linking reclaimed water with power plant cooling. These metrics include de facto reuse (representing the incidental presence of wastewater in a surface water resource), infrastructure cost, power generation efficiency loss due to increased water temperatures, and downstream water quantity impacts. A case study of Chicago, Illinois, and the surrounding area is introduced to demonstrate the method’s applicability in jointly planning for water and energy. Findings reveal that the impacts of wastewater reuse are complex. While the infrastructure necessary for reuse is economically feasible, some power plants have high ratios of de facto reuse due to dense urban populations, which devalue the reclaimed water infrastructure investment. Additionally, the power generation efficiency gains made from the cooler and more reliable temperature of reclaimed water must be weighed against the inherent interbasin transfers that occur. These metrics summarize some of the considerations when sustainably managing both energy and water resources.