A review of major non-power-related carbon dioxide stream compositions

A critical component in the assessment of long-term risk from geologic sequestration of carbon dioxide (CO2) is the ability to predict mineralogical and geochemical changes within storage reservoirs as a result of rock-brine-CO2 reactions. Impurities and/or other constituents in CO2 source streams selected for sequestration can affect both the chemical and physical (e.g., density, viscosity, interfacial tension) properties of CO2 in the deep subsurface. The nature and concentrations of these impurities are a function of both the industrial source(s) of CO2, as well as the carbon capture technology used to extract the CO2 and produce a concentrated stream for subsurface injection and geologic sequestration. Most work on CO2 capture, utilization, and storage has been focused on large fossil-fuel-fired power plants. This article reviews the relative concentrations of CO2 and other constituents in exhaust gases from other major non-power-related industrial point sources. Assuming that carbon capture technology would remove most of the air (i.e., incondensable gases N-2, O-2, and Ar) from the exhaust gases, the authors summarize the relative proportions of SO2, NOx and other remaining impurities expected to still be present in non-power-related CO2 source streams that could be targeted for geologic sequestration. The summary is presented relative to the four largest non-power-related sources of CO2: (1) use of fossil fuels as carbon feedstock, (2) iron, steel, and metallurgical coke production, (3) lime and Portland cement production, and (4) natural gas processing and industrial heat/steam generation.