Sustainable Environmental Engineering

13Green Retrofitting and Remediation

Cost of inaction is far higher than the interruption cost by a disaster.

OBJECTIVES

• To conduct energy auditing to improve energy efficiency in WWTPs
• To introduce innovative technologies of anaerobic digester to increase energy efficiency
• To identify innovative ways such as microsieving to divert organic matter in wastewater to anaerobic digester
• To determine the energy consumption of mechanical dewatering
• To quantify energy generation through anaerobic digestion of sludge
• To reduce the footprint of remediation projects through green remediation
• To present the US EPA green remediation procedure and tools

13.1 Principle 10

Wastewater treatment plant (WWTP) is the critical infrastructure in the water–food–energy nexus. Currently more than 15 000 and 5 000 WWTPs were designed and built according to the conventional design principle in the United States and China, respectively. However, 99% of these plants were currently energy negative. In the next decade, retrofitting these WWTPs to energy‐positive water resource recovery facility (WRRF) could be the major task for SEE designers in both the developed world such as the United States and EU and the developing countries such as BRIICS. Due to different designs and combinations of different unit processes, retrofitting strategies will be different. In addition, solar energy could be added to the WRRF to reach the retrofitting targets. For developing countries, remediation of contaminated ...