Device and method for sequestering a substance

A device for sequestering a substance, comprising:

• an injection well extending to a brine aquifer;
• a pumping apparatus for pumping to the injection well a substance which includes at least one of carbon dioxide, a substance higher in water solubility than carbon dioxide, and methane;
• and
• a porous member of ceramic provided in the vicinity of a tip of the injection well, wherein:
• the porous member is formed through firing of a mixture of ceramic particles and a binder for binding the ceramic particles together, a mode of a pore size distribution is 28 μm or less and a full width at half maximum of the pore size distribution is 6.0 μm or less,
• the substance pumped into the injection well can be injected into the brine aquifer via the porous member,
• the substance injected from the porous member into the brine aquifer is in a liquid state, a gaseous state, or a mixed state thereof, and
• in the course of injection of the substance from the porous member into the brine aquifer, microbubbles of the substance are generated.