Monitoring Real Time, In-Line Variations of Noble Gas Concentrations During CO2 Capture Operations by Means of a Portable Mass Spectrometer

Abstract

In the ICO2P-project the overall aim is to develop an innovative and cost-effective monitoring scheme for CO2 capture and storage operations, implementing new methods for in situ noble gas measurements. The first step is to establish a basis for fluid source identification by recording temporal variance of noble gas composition in CO2 product. Studies of noble gases related to CCS typically include few, single point samples. In ICO2P, a portable mass spectrometer (i.e. miniRUEDI) is utilized to directly measure real time variability of the noble gas content in CO2 gas streams at operating CCS facilities. The first study was performed at the Technology Centre Mongstad (TCM) in Norway, a large-scale test facility for post-combustion CO2 capture operations. During an open scientific test campaign for amine-based capture (TSA-MEA), noble gases (He, Ar, Kr) as well as CO2, N2, O2 concentrations in the CO2 product stream were recorded every 10 to 15 minutes during a 5-day period. He concentrations (<0.001ppm)were depleted post-capture and too low for temporal variation measurements in the CO2 product line. Ar concentrations (0.15 – 0.65 ppm) were significantly higher and temporal variation was successfully recorded in the CO2 product line. Ar was found to be sensitive to capture operations, e.g. CO2 recycling ratio. This new approach will provide knowledge of the uniqueness and variability of inherent noble gas fingerprints and depletion/absorption during CCS operations and provide grounds for comparison between fluid origins needed in leakage detection schemes at CO2 storage sites.