European Commission logo
English English
CORDIS - EU research results

Real-time assessment of toxic sulphide in wastewater – market maturation of an Industrial Micro Electrochemical Cell

Periodic Reporting for period 2 - iMEC (Real-time assessment of toxic sulphide in wastewater – market maturation of an Industrial Micro Electrochemical Cell)

Reporting period: 2019-10-01 to 2020-09-30

Hydrogen sulphide (H2S), a toxic, foul-smelling, and highly corrosive gas, is a major challenge in wastewater collection systems where it causes the premature deterioration of sewer pipes, wells, pumps, motors, and other assets. In addition to accelerated asset deterioration, the gas also poses significant worker safety concerns, and “rotten-egg” odour nuisances with a severe negative impact on the quality of life for affected residential areas. It is estimated that the annual worldwide direct cost of asset corrosion in the wastewater industry exceeds €1.4 trillion.

To avoid the negative effects of hydrogen sulphide, water utilities spend a significant share of their operating budgets on mitigation initiatives including the dosing of neutralization agents (chemicals), but as the gas is notoriously difficult to measure in the harsh environments found in sewer systems, mitigation actions are often inefficient. Without a clear overview of the real-time development of hydrogen sulphide in complex sewer systems, utilities often dose chemicals in excess and are forced into making long-term asset management decisions on an uninformed basis.

Existing sensor solutions typically measure hydrogen sulphide in the gas phase only, however, the data collected by these sensors does not provide a full overview of the challenge, as they often underestimate hydrogen sulphide levels and as they are unsuitable for deployment in many sewer environments.

Based on the extensive knowledge in developing, constructing, and applying microsensors, SulfiLogger has developed a cost-effective and robust sensor for continuous monitoring of liquid-phase hydrogen sulphide in wastewater collection systems. Built for long-term deployment in extreme environments, the novel sensor enables utilities to map the development of hydrogen sulphide in sewer systems in real time. Using this approach, the sensor technology enables utilities to; cost-optimize chemical dosing strategies to reduce operating costs, locate the source of hydrogen sulphide development in complex sewer networks for efficient mitigation, and make long-term planning decisions on an informed basis to increase the lifespan of assets.

The liquid-phase measurements of the SulfiLogger™ sensor represents a radically new approach to hydrogen sulphide monitoring in the wastewater industry, and the overall objective of this project was thus to overcome prominent barriers of entry that may hinder the market uptake of the new technology and to mature the technology and its production processes, and clearly demonstrate the sensor’s value-added benefits through large-scale demonstrations and product certification.

Through two major demonstration phases, the project successfully demonstrated how continuous, liquid-phase measurements of hydrogen sulphide can provide significant benefits for a range of different applications.
Throughout the project, the SulfiLogger™ sensor technology has been continuously refined to match end-user requirements, and production techniques and processes optimized and streamlined in preparation for production ramp-up. Parallel to this, a series of initiatives have been taken to prepare the commercial uptake including the obtainment of certifications required for entry on key markets.

Sensors were installed first in an initial field test and thereafter in a major demonstration campaign at both national and international water utilities across major European wastewater markets. These demonstrations successfully showed that the sensor technology provides distinct advantages within the field of hydrogen sulphide monitoring in the wastewater industry, and that these insights enable significant benefits not only for individual wastewater utilities but also for the environment and society at large. Among other results, the demonstrations have shown how the technology can be applied to evaluate, optimize, and directly control chemical dosing systems for significant efficiency gains. The results have also shown how the technology can play a vital part as a tool to map and prioritize hydrogen sulfide hotspots in complex sewer systems, to evaluate the effect of various hydrogen sulphide mitigation activities, and to optimize hydraulic models.

The results have been disseminated to key stakeholders and the general public continuously throughout the project at leading international tradeshows and conferences (including WEFTEC and Aquatech), through online presentations, on a dedicated website, via case study flyers, and using online social media channels.
The problems caused by hydrogen sulphide in wastewater collection systems is only expected to grow in years to come as the ongoing centralization of wastewater treatment plants, increasing stormwater separation, decreasing water consumption, and general urbanization trend all unfortunately provide ideal conditions for the formation of the toxic gas in sewer systems. The lack of existing measurement technologies for smart monitoring hinders efficient mitigation and as an effect, new technologies are urgently demanded by the industry.

A successful commercialization and subsequent market adaptation of the SulfiLogger sensor technology represents a unique business opportunity with many beneficial impacts from sustainability, environmental and societal points of view, and is well aligned with UN sustainability development goals for clean water, sustainable cities and innovations in infrastructure.

Improved strategies for the dosing of neutralization agents will reduce the amount of (unspent) chemicals used in the wastewater industry, which in turn provides improved environmental compliance and reduced operational costs for water utilities. An optimized approach to hydrogen sulphide monitoring and mitigation in sewer networks enabled by the SulfiLogger™ sensor will drastically improve the quality of life for people living near affected areas and the working environment for sewer technicians as odour nuisances and toxic gas releases are eliminated. The SulfiLogger™ sensor will also play an important role in avoiding property devaluation for affected houseowners caused by frequent H2S odours and all the multi-layered consequences for the general society inherent to the collapse of critical infrastructure.

Besides providing SulfiLogger™ with a sustainable competitive advantage and export potential, this project will assist Europe in achieving objectives for environmental and quality of life policy. Overall, this opens not only an important economic opportunity for SulfiLogger™ but will ultimately lead to a more sustainable wastewater treatment process and important cost-savings in the industry.