Evaluation of environmental impacts for future influent scenarios using a model-based approach

Area of Science:

• Environmental Engineering
• Water Treatment Technologies
• Life-Cycle Assessment

Background:

• Influent characteristics significantly impact wastewater treatment plant (WWTP) performance.
• Variations in wastewater dilution due to sources like infiltration and surface runoff pose challenges to consistent WWTP operation.
• Quantifying the environmental consequences of these influent changes is crucial for sustainable water management.

Purpose of the Study:

• To develop and apply a model-based approach for assessing the environmental impacts of varying wastewater influent scenarios on WWTPs.
• To simulate WWTP performance under different influent conditions, specifically focusing on infiltration and surface runoff.
• To evaluate the environmental footprint associated with these changes using Life-Cycle Assessment (LCA).

Main Methods:

• Generation of realistic influent scenarios incorporating variations in dilution.
• Utilization of a dynamic, plant-wide process model of a wastewater treatment plant.
• Application of Life-Cycle Assessment (LCA) to quantify environmental impacts based on simulated operational data.

Main Results:

• Increased wastewater infiltration led to a higher environmental impact per kilogram of nitrogen removed.
• The study observed a minor impact on environmental performance attributable to increased surface runoff.
• Model simulations provided quantitative insights into the differential effects of infiltration versus surface runoff.

Conclusions:

• Infiltration poses a greater environmental burden on nitrogen removal in WWTPs compared to surface runoff.
• Dynamic modeling and LCA are effective tools for evaluating the environmental implications of influent variability.
• Wastewater management strategies should consider the distinct impacts of infiltration and surface runoff to optimize environmental performance.