Fundamental Research for CO2 Injection into Granite and Sandstone in Experimental Hot Water Systems

Abstract

Experiments were conducted using a batch type micro-autoclave, over a temperature range of 100-350?C, to understand granite and sandstone reactions in hot water, in the absence or presence of excess CO2. Our one-week experiments show that the dissolution of granite, and deposition of secondary minerals, is enhanced by the presence of excess CO2. Combining the results of sample weight and CO2-gas volume change, we show CO2 could be fixed in the rock, by deposition of secondary minerals. We suggest that it may be possible for granite or sandstone to 'capture' CO2, and that underground disposal may be a feasible solution to reducing atmospheric emission of CO2.