New technology deploys highly accurate sensors to detect greenhouse gas emissions from wastewater treatment and agriculture, thereby monitoring the impact of fertilisers on the environment
A collaboration between the University of Portsmouth and B4T, a Hampshire-based product design house that specialises in the Internet of Things, aims to significantly reduce the carbon footprint of utility operators and farmers.
Why nitrous oxide?
In addition to carbon dioxide (CO2), there are several other gases that contribute to climate change. Nitrous oxide (N20) – which is produced in soils during farming and when removing nitrates from wastewater – contributes about 300 times the global warming potential of CO2. It is therefore essential that this is considered when monitoring waste water plants or farms.
Human activity affects the nitrogen cycle when nitrogen is added to ecological and engineered systems as fertiliser, organic matter or wastewater. Denitrification can be promoted in wastewater treatment plans or wetlands to remove the chemical from effluents, or else it can happen at enhanced rates in the environment when nutrient rich runoff is exposed to reducing conditions. These process and soil emissions have meant that the wastewater treatment, agricultural and waste management sectors have become increasingly concerned that they won’t meet Net Zero emissions.
The sensors
The collaboration produced a set of miniaturised, low-cost sensors called Manga [Monitoring Ammonia and Nitrogenous Greenhouse Gases] and software for farmers and utility operators to help them monitor emissions. The sensors focus on N2O in particular as it is a potent greenhouse gas whose management is an important part of the Net Zero strategy for targeted sectors.
Realtime information from rural locations is processed, and visualised, to have wide appeal and make decision support effective.
B4T already delivers best-of-breed Man-o-War sensors, currently used in horticulture with technology developed for maritime air quality. It has further developed its software to enable the IoT sensor output to be turned into meaningful data as part of an auditable blockchain.
The University of Portsmouth undertook field trials, using the facilities of the Environmental Technology Field Station (ETFS) at a wastewater treatment plant in Hampshire, to validate and seek accreditation for the sensors. This involved developing deployment protocols for assessing whole site and individual unit process level emissions.
Professor John Williams, academic lead for the project said: “Monitoring wastewater emissions usually involves extrapolating information from dissolved gas measurements or using bulky expensive devices or diffusion tubes, which lack resolution over time.”
“We are developing a set of miniaturised, low-cost sensors to monitor emissions – with a particular focus on N20. Reducing emissions of this potent greenhouse gas is an important part of the Net Zero strategy for agriculture and wastewater management sectors.”
Alex Barter, managing director at B4T said: “This approach to tackling a hidden greenhouse gas monster is precisely where we play to our strengths, generating new evidence to contribute to policy and water company operations.
“It is our pleasure to once again join forces with the University of Portsmouth on vital environmental work. We look forward to collaborating with the domestic and global wastewater processing sector and are open to discussing our project.”
The Manga project will seek MCERTS accreditation for the technology. Once approved, it can be offered to the water and waste sectors at industry facing conferences and other events.
The project recently received £359,289 from Innovate UK, part of a body called UK Research and Innovation (UKRI).
For more information visit: www.b4t.org www.port.ac.uk
