An apparatus comprises a separator, a compressor, a mixer and a pump. The separator operates on an input gas mixture comprising carbon dioxide gas and one or more other gases, providing a separated carbon dioxide gas output. A compressor compresses the separated carbon dioxide gas output, providing a second output comprising at least one of gaseous carbon dioxide and liquid carbon dioxide. A mixer mixes the second output with liquid water under pressure to provide a third output comprising: at least one of liquid carbon dioxide and gaseous carbon dioxide; and water with dissolved carbon dioxide. A pump pumps the third output into an underground structure such that components of the third output react with available rock surfaces to form stable carbonates.

An apparatus comprises a separator, a compressor, a mixer and a pump. The separator operates on an input gas mixture comprising carbon dioxide gas and one or more other gases, providing a separated carbon dioxide gas output. A compressor compresses the separated carbon dioxide gas output, providing a second output comprising at least one of gaseous carbon dioxide and liquid carbon dioxide. A mixer mixes the second output with liquid water under pressure to provide a third output comprising: at least one of liquid carbon dioxide and gaseous carbon dioxide; and water with dissolved carbon dioxide. A pump pumps the third output into an underground structure such that components of the third output react with available rock surfaces to form stable carbonates.

Methods and systems for thermal energy storage and enhanced oil recovery are described herein. In some embodiments, natural gas may be injected down a well which has been previously hydraulically fractured to store thermal energy and to stimulate the well to greater hydrocarbon production.

An example system is configured to manage the storage of water underground using a sensor-based grid system. The example system includes wells, each of which is between a surface and an underground formation capable of storing water received from the surface. The example system includes pumps, at least of which is associated with each well to force water from the surface, through the well, into the underground formation. The example system includes sensors, at least of which is associated with each well. The sensors are configured to communicate sensor data wirelessly. The example system also includes a computing system configured to receive sensor data from each of the sensors and to control operations of one or more of the pumps based on the sensor data.

An apparatus of salt cavern gas storage without cushion gas includes: a salt cavern; sediments; a drainage assembly; a gas injection and production pipe; a debrining string, one end of which is connected to the drainage assembly, and the other end of which protrudes from the ground to be connected to a water source assembly; a communicating assembly, which is used to make the gas injection and production pipe be in communication with the debrining string on the ground. A closed loop is formed by making the gas injection and production pipe and the debrining string be in communication with each other on the ground through the communicating assembly, thus the non-cushion gas injection-production operation of sediment particles in the salt cavern is realized.

A water storage and management system takes water from a water source, such as captured run-off, and through a piping system, directs a flow of the water into an aquifer for storage and future utilization. Using moisture detectors, the system ascertains the water content of different layers or zones of the aquifer and reports this information to a digital processor. The digital processor may utilize this information to issue instructions to one or more control valves to direct the flow of the water into portions of the aquifer which have additional storage capacity. The digital processor may also instruct a submersible pump to withdraw from the aquifer as desired. This system is utilized in a method of banking groundwater from a remove location. Such groundwater storage may result in receipt of groundwater recharge credits.

A geological storage system of carbon dioxide according to an exemplary embodiment of the present invention includes: an injection pipe that extends to a carbon storage reservoir that includes a plurality of rock grains and brine, from the ground surface, and supplies an injection material that includes carbon dioxide (CO.sub.2) to the carbon storage reservoir; a plurality of pores that are disposed between the plurality of rock grains; and a storage structure that is connected with a part of the plurality of pores and where the carbon dioxide reaches through the plurality of pores and then stored.

A water storage and management system takes water from a water source, such as captured run-off, and through a piping system, directs a flow of the water into an aquifer for storage and future utilization. Using moisture detectors, the system ascertains the water content of different layers or zones of the aquifer and reports this information to a digital processor. The digital processor may utilize this information to issue instructions to one or more control valves to direct the flow of the water into portions of the aquifer which have additional storage capacity. The digital processor may also instruct a submersible pump to withdraw from the aquifer as desired.

A novel method for storing high purity hydrogen into a salt cavern is provided. Particularly, the storage process involves confining the high purity hydrogen at a certain pressure in a salt cavern without seepage or leakage of the stored hydrogen through the salt cavern walls. The pressure in the cavern is maintained during storage of the high purity hydrogen.

A drain-back check valve assembly includes a body having a passageway with an inlet and an outlet. A bypass port extends from the passageway to an outer surface of the valve body. A main poppet valve assembly is disposed in the passageway and moveable between a closed position which prevents fluid flow from the outlet to the inlet and an open position which allows fluid flow from the inlet to the outlet. The main poppet valve assembly includes a poppet and a spool guide fixed to the poppet. The guide has a sidewall which includes a drain-back port. When the main poppet valve assembly is in the closed position, the drain-back port is aligned with the bypass port. When the main poppet valve assembly is in the opened position, the drain-back port is not aligned with the bypass port.