Carbon dioxide/limestone/water emulsion for ocean and geologic sequestration of CO2

Preliminary laboratory experiments demonstrated that liquid or supercritical CO2 form a stable emulsion in water when stabilized with pulverized CaCO3 (mean particle diameter 10-20 mum). Tiny globules Of CO2 (200-300 mum) are formed, surrounded by a thin sheath (10-20 mum) of CaCO3 particles, dispersed in water. The proportion by weight Of CO2 to CaCO3 in the experiments was about 10:4, but not all the CaCO3 was used up in the encapsulation. The encapsulated globules are heavier than water because they settle at the bottom of the water column. The stable emulsion has implications for both ocean and geologic sequestration Of CO2. When released below the flash depth of liquid CO2 (below 500 in), the encapsulated globules may sink to the ocean bottom, prolonging the sequestration period Of CO2, and minimizing its environmental impact. When released in dry or wet geologic reservoirs, the encapsulated globules may settle at the bottom of the reservoirs, rather than buoying to the top as pure, supercritical CO2 would.