Damien Weidmann1,2, Johnny Chu1, Annika Voss1, Patrick Yeates1, Arun Kannath1, Neil Macleod2, Richard Brownsword2

1. MIRICO Ltd, Harwell Campus, Didcot, OX11 0QX, UK2. Space Science & Technology Dept, Rutherford Appleton Laboratory, Harwell Campus, Didcot, OX11 0QX, UK

This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 764810

Gas emission monitoring instrument development and deployment for geo-energy operations

Science for Clean Energy project objectives• Develop, install, and test technologies to continuously, reliably, and cost effectively

monitor the environmental risks related to sub-surface geo-energy operations.• This includes building novel cutting edge instrumentation and data interpretation

methodologies, especially for stray gas emissions at well sites.Gas emissions activities• Develop wide area gas emission source mapping to locate, quantify, and monitor

fugitive releases at surface level of CH4, CO2, and potentially C2H6.• Develop in-situ, real time isotopic analysis systems for gas sources characterization

and discrimination, starting with 13CO2/12CO2.• Deploy and test novel instrumentation at the S4CE test sites: Carbfix, Iceland;

Geothermal Engineering, UK; St Gallen, Switzerland.• Process instrument data towards producing relevant reporting.

1. Gas emission monitoring rationale & objectives

• Multi-directional high precision open-path concentration measurements.• Use of middle infrared (2-20 µm) lasers to boost sensitivity and reduce scattering.• Use of novel proprietary dispersion spectroscopy ideal for harsh field deployment.

2. Principles of gas emission mapping

Temporal evolution of integrated CH4 concentration over 7 paths1s resolution - ~10 ppbv precision - ~1 ppm.m/√Hz

Path averaged gas concentrations in line of sight correlated to:- wind strength, direction,

and turbulence,- gas source locations

and mass emission rates.

Knowing meteorological data, Bayesian inversion methods can be used to infer estimates of source

location and emission rates as well as uncertainties.

• Open-path sensing• Path-integrated measurement ≠ point sensing• No sample handling

• Tuneable Mid IR Laser• High brightness, high SNR• High beam directionality• Fundamental molecular transition bands• Less scattering

• Molecular Dispersion Spectroscopy• Dynamic range• Immunity to transmission change• Selectivity

• Implementation• Long Wave IR Prototype (7.7 µm)• Mid Wave IR Prototype (3.3 µm)• Multi-beam for emission source mapping

• From spectra to concentrations• Full physics forward

3. Optical dispersion laser open path sensor technology

Sensor Retro-reflectorPlume

X 1000Bending mode ν41367 cm-1

Stretching mode ν33157 cm-1

Using MOLECULAR DISPERSION:- Linear- Maintain sensitivity- >106 dynamic range- Information in the phase- Immune to transmission change- Maintain selectivity

Demo on a foggy day

First deployment test campaign in partnership with Bill Hirst and Marcella Dean, SHELL GSI, The Netherlands• Controlled releases of CH4 in the range of up to ~2kg/hr.• Simulation of diffuse sources ~2m x 2m.• Open area of ~50 x 200 m at the Chilbolton Observatory site, UK.• 19 releases of ~1 hour..

Retrieved results by SHELL software (B. Hirst, M. Dean)

4. Test deployment campaigns

Open path emission mapping system• Second trials have been performed to further develop the mapping software.• First light with currently being assembled novel productized system.• New 360º 2D scanning head with automatic retroreflector registration.• New fast electronics.

6. Productized system development status

Technology inherited from planetary and geochemistry instrumentation• First field deployment supported by DCO for demonstration of real-time 12C/13C measurement in fumaroles.• Objective is to offer same performances as large Isotopic Ratio Mass Spectrometers in a compact format.• Chemical versatility is traded off.• Use of ultra-fine laser spectroscopy to interrogate chemical bonds and discriminate isotopologues.

5. Laser isotopic ratio analyser technology

Diffuse source made of perforated plastic membrane

Sonic 3D anemometer installed within the beam fan

Some of the retro-reflectors installed at the field

Location 2 : 1.38 kg/hr actualLocation 1: 1.35 kg/hr actual

Location 3&4: 2x 1.24 kg/hr actual Location 3: 1.47 kg/hr actual

Deployment at Geothermal Engineering Ltd, UK• CH4 measurements prior to drilling operations to capture and measure the background.• Second set of measurements once the wells are in place.

Top view with beam array

View during measurements

360°

500m

ppb

Laser isotopic ratio analyser• Novel high performance multipass cell patented.• Multipass cell test underway for integration.• Ultra-miniaturize system demonstrated.• Study on biases and accuracy.

Contact and info• damien@mirico.co.uk• www.mirico.co.uk• damien.weidmann@stfc.ac.uk• http://www.ralspace-spectroscopy.com