The aim of AQUARIUS was to provide an online and inline capable mid-IR sensing solution that meets the legal provisions for industrial waste water and drinking water monitoring. To achieve the required sensitivity, the employed laser source and detector had to be improved and combined with an innovative sample extraction method. In addition, waveguides were functionalized with polymers to further improve the limit of detection. The continuous improvements throughout the project allowed measurement campaigns at industrial productions sites and drinking water treatment plants.
As fresh water is essential for human wellbeing and the world economy, its quality is regulated by national and international legislation. Although it is the most abundant substance on Earth’s and used in almost every industrial process (directly or indirectly), fresh water comprises only a small fraction of the total amount of water. It is essential to ensure a good quality of this resource, even though the composition of fresh water can differ significantly. In particular, both, the concentration and the type of the dissolved substances, can vary and are a challenge to the water sector. Thousands of these compounds are used every day and new ones are continually put on the market. Specialized laboratories employ highly optimized detection techniques to measure their presence at low concentrations. Novel water monitoring technologies are needed for all types of water including process water, waste water, sewage and drinking water. These new technologies shall enable pervasive water monitoring which can replace and complement currently laboratory based offline methods by online or inline monitoring strategies.
The AQUARIUS project addressed the development of a new generation of photonic sensing solution in response to the need for pervasive sensing for a safer environment. In particular, components, modules, sub-systems and systems were developed to enhance the sensitivity and specificity measurements in water monitoring. They should adhere to the requirements of regulatory bodies, as well as the needs of selected end-users such as waterworks and the oil producing industry. The main focus in AQUARIUS was the detection of hydrocarbon contaminations (oil in water). AQUARIUS aimed to provide improved quality and effectiveness of online and inline sensors allowing a reliable and continuous real-time monitoring on site. This was achieved by improving external cavity (EC) quantum cascade lasers (QCL) and optimizing suitable detectors. The following key objectives have been addressed by AQUARIUS:
• O1: Enhancement of broadband tunable quantum cascade lasers in terms of spectral coverage and noise (TRL increase: from 4 to 6)
• O2: Realisation of a fully functional spectrometer sub-system consisting of a μEC-QCL and a fast MCT detector including data acquisition (TRL increase: from 3 to 6)
• O3: Advance Oil-in-Water (OiW) monitoring capabilities from offline (state-of-the-art) to online (TRL increase: from 3 to 6)
• O4: Test of the online OiW system at industrial end users (TRL 7)
• O5: Realisation of integrated optical circuits (IOCs) for waveguide based sensing and inline capable sensing configuration (TRL increase: from 2 to 4)
• O6: Assembly and test of the inline OiW system in a laboratory environment (TRL increase: from 2 to 4)