Name

An innovative approach to nitrous oxide emissions monitoring using soft sensors

Speakers

Kenneth McGibbon, Hamish Todd

Authors

Kenneth McGibbon, Ralitza Nikolova-Kuscu and Laura Fonseca, Mott MacDonald, UK
Helene Hauduc and Ferenc Házi, Dynamita, France
Hamish Todd and Chris McNeilly, Scottish Water, UK
Sam Chowdhury, Air Technology Ltd, UK

Description

Accurate site-specific measurement of wastewater treatment nitrous oxide (N2O) emissions is crucial for baselining greenhouse gas emissions and developing N2O mitigation strategies. Traditional methods involve measuring N2O in the liquid phase, collecting air flow data and calculating the emissions to atmosphere using empirical algorithms. However, this approach faces challenges due to the lack of reliable air flow data in specific zones of activated sludge plants, leading to inaccurate assumptions or costly installations of new air flow meters. In some cases, no accessible, safe location to install air flow meters is available.

This abstract proposes an alternative approach using SUMO mechanistic models as ‘soft sensors’ which back-calculate air flows and mass transfer coefficients (kLa) using readily available site data (e.g., dissolved oxygen, ammonia, temperature). The ‘soft sensor’ data is combined with measured liquid phase N2O data to calculate the mass transfer of N2O to the atmosphere. This method aims to reduce costs, time, and effort, whilst improving operational safety risks in installing air flow meters. The goal is to make N2O monitoring more efficient and widespread. The implementation of this strategy in Scotland and New Zealand is discussed, along with its wider applicability.

Time

2:55 PM - 3:20 PM

Location Name

Room 1

Track

10:05 - 17:30 Process Emissions