Robust Split Laser Sensor for Harsh Environment Sensing Applications

Geologic carbon storage (GCS) is a promising technology used to lower the net release of CO2 into the atmosphere. Herein, the CO2 is captured and injected into deep geological formations, e.g., saline aquifers. The underlying premise behind success of this technology is that the stored CO2 does not escape from the host formations. However, the interaction of CO2 with the reservoir rocks, causes reactions that release metal contaminants into shallow groundwater aquifers. Monitoring of groundwater for elevated levels of dissolved metal contaminants such as Ca, K, Sr, etc., could provide an early detection of CO2 leakage needed for long-term CO2 sequestration monitoring. Technologies are also needed for direct and in situ measurements of greenhouse gases, CO2 and CH4 for assessment of air, water and soil quality required for environmental monitoring. For in situ measurements and real-time analysis, we propose to employ the DOE patented split laser measurement technology (SLMT) for laser induced breakdown spectroscopy (LIBS) to measure elemental species (Ca, K, Sr) and Raman spectroscopy to measure CO2 and CH4 under harsh environmental conditions relevant to fossil energy and carbon management. A significant part of the effort will be devoted to the upgrade of the current SLMT by incorporating innovative packaging and sealing of the sensor head for ruggedness and to withstand harsh environments during underwater and downhole sensing applications. The proposed system will support laser induced breakdown spectroscopy (LIBS) and Raman scattering measurements of gases, liquids, and solids. There is a great need in providing an inexpensive and compact measurement device suitable for harsh environments underground and on the surface to monitor elemental species such as Ca, K, Sr, etc. for detection of CO2 leakage, and dissolved greenhouse gases such as CO2 and CH4 for groundwater monitoring in real time. The capability of LIBS and Raman scattering enables real-time assessment of air, water, and soil quality, which is highly important to oil and gas exploration companies, landowners, regulatory agencies, municipalities, and any organization measuring emissions and pollutants.