The invention discloses a
coal underground efficient gasification method based on
calcium-based catalyst injection and a
carbon dioxide geological storage method. The
calcium-based
powder material adopts high-purity limestone, wherein the content of
calcium oxide is greater than 50%. The method comprises the following steps: crushing a limestone
raw material into micron-scale to nano-scale
powder, putting the
powder into a stirring device, mixing the powder with a
coal underground gasification injection agent to obtain a suspension fluid, and injecting the suspension fluid into a
coal underground gasification furnace which is in production;
calcite minerals in limestone are decomposed into
calcium oxide under the coal underground gasification high-temperature effect, and the
calcium oxide adsorbs water and
carbon dioxide to the surface of coal
coke to generate a synergistic gasification reaction at the same time. Wherein the injectant and the calcium-based
powder suspension fluid are prepared by adopting a foam suspension device provided with an
ultrasonic generator, so that the suspension stability of the calcium-based powder in the suspension fluid is improved. According to the invention, the calcium-based material is injected into the coal underground gasification furnace as the catalyst, so that the
moisture,
carbon dioxide and carbon in the coal are subjected to co-gasification reaction, the coal underground gasification
reaction rate and gasification efficiency can be obviously improved, the environmental
pollution is reduced, and the maximum utilization of resources is realized.