Fluctuation Enhanced Sensing (FES) for Monitoring of CO2 Storage

In order to achieve a less than 1.5°C temperature rise, tens of Gigatons of CO2 must be captured and sequestered per year. Geologic storage of captured CO2 will play a vital role in achieving this goal. To ensure safe storage, monitoring, verification, and accounting (MVA) of the CO2 is needed. However, current sensor techniques for detecting and monitoring CO2 gas have been developed overwhelmingly for surface or atmospheric monitoring and options are limited for deep subsurface monitoring. In this SBIR project TDA will develop a robust CO2 sensor for continuous monitoring of supercritical CO2 at the high pressures and elevated temperature conditions thousands of feet underground. This sensor passively responds to the presence of CO2 with no mechanical parts. It uses a CO2 sensitive material, novel design and advanced data processing to achieve the needed sensitivity and durability. In the Phase I project we will experimentally establish the limits of detection of the new sensor. We will prepare sensors materials and construct a prototype. We will demonstrate the performance of the sensor in a column of soil at the temperature and pressures characteristic of deep, bore-hole environments. This sensor technology will ensure safe CO2 storage by providing accurate information on the CO2 concentrations in the deep subsurface. This is important for planned wide scale CO2 capture and geologic storage. Moreover, it is important for the large amount of that is already injected in enhanced oil recovery (EOR). Our sensors technology will provide direction information on the CO2 concentration in the subsurface not available today. The CO2 EOR industry could also benefit from monitoring to understand how and where to inject CO2 in addition to providing safety assurance.