Multi-wavelength tunable lasers for gas spectroscopy

In process industry, environmental and medical applications, it can be important to measure the concentration of many gas species simultaneously and rapidly, to give real-time information. Examples include; - Measurement of combustion feedstocks and effluent gases, important in the drive for reduced carbon emissions. - Detection of hydrocarbons and hydrogen sulfide in the natural gas industry and biogas generation industries - Detection of toxic species in industry, such as ammonia and hydrogen fluoride - Breath gas diagnostics, to diagnose and anage diseases such as asthma, diabetes, renal disease, cystic fibrosis and others. - Measuring short-lived gas species, to improve urban air quality and understand important atmospheric processes affecting climate change. These activities present a significant measurement problem to industrial users. Industrial gas detection is dominated by complex and expensive laboratory equipment with sampling that precludes real-time measurement and can even affect the composition of the sample through condensation and / or reaction in the sample pipework. Small ultra-low-cost devices are also available, however these do not offer the stability nor the gas species specificity needed for industrial applications. Many gases of interest absorb light at specific and characteristic wavelengths in the near infrared region of the spectrum (1.3 - 2.5 microns). Using a suitable laser source whose emission is at known and controlled wavelengths, this property forms the basis of a powerful method to detect gases and measure their concentrations.Our new approach to optical gas detection, based on development of a new class of optical sources, will enable both multi-species detection as well as detection of unstable species, both of which are difficult to impossible with existing technology. Demonstration of these sources will initially include detection of hydrocarbons, carbon dioxide and carbon monoxide, then lead on to measurement of unstable species such as hydrogen sulfide and ammonia..

Potential beneficiaries are as follows: 1. Users in the private and public sectors cover a wide variety of applications in safety, process control, environmental monitoring and medical applications already discussed. This group includes workers who may benefit from improved detection of toxic gases. The wider public will benefit from the resulting improvements in process efficiency, reductions in greenhouse emissions, improved air quality and non-invasive medical diagnostics. 2. Gas sensor and instrumentation manufacturers will benefit by extending their markets to include new gas species, multi-species detection and niche applications for which custom wavelength sources are hard to find, and from the improved device performance that we also expect to follow. This sector is particularly strong in the UK and supports a large and diverse industry. It includes our project partner Geotechnical Instruments Ltd. Our research team has a strong track record in exploiting new technology and in technology transfer. We have good established links with potential future partners in device fabrication and gas detection, through previous and existing collaborations and through active involvement with an important technology club - the UK Gas Analysis and Sensing Group (GASG). Our plan is to continue to engage with and expand this network, culminating in a free-to-attend dissemination workshop towards the end of the project. Our exploitation strategy will consider various options: licensing technology to commercial partners, exploitation via a spin-out company such as our partner Stratophase Ltd, and technology transfer of new spectroscopic detection techniques to gas detection companies.