Use of Treated Municipal Wastewater as Power Plant Cooling System Makeup Water: Tertiary Treatment versis Expanded Chemical Regimen for Recirculating Water Quality Management.

摘要

Treated municipal wastewater is a common, widely available alternative source of cooling water for thermoelectric power plants across the U.S. However, the biodegradable organic matter, ammonia-nitrogen, carbonate and phosphates in the treated wastewater pose challenges with respect to enhanced biofouling, corrosion, and scaling, respectively. The overall objective of this study was to evaluate the benefits and life cycle costs of implementing tertiary treatment of secondary treated municipal wastewater prior to use in recirculating cooling systems. The study comprised bench- and pilot-scale experimental studies with three different tertiary treated municipal wastewaters, and life cycle costing and environmental analyses of various tertiary treatment schemes. Sustainability factors and metrics for reuse of treated wastewater in power plant cooling systems were also evaluated. The three tertiary treated wastewaters studied were: secondary treated municipal wastewater subjected to acid addition for pH control (MWW-pH); secondary treated municipal wastewater subjected to nitrification and sand filtration (MWW-NF); and secondary treated municipal wastewater subjected nitrification, sand filtration, and GAC adsorption (MWW-NFG).