A method for storing very high purity hydrogen in a salt cavern is provided. The method includes introducing a compressed very high purity hydrogen gas into a salt cavern, thereby producing a stored very high purity hydrogen gas; maintaining the stored very high purity hydrogen gas at a pressure greater than about 1.0 psi per linear foot of height within the cavern, and less than about 4.0 psi per linear foot of height within the cavern.

A method for storing very high purity hydrogen in a salt cavern is provided. The method includes introducing a compressed very high purity hydrogen gas into a salt cavern, thereby producing a stored very high purity hydrogen gas; maintaining the stored very high purity hydrogen gas at a pressure greater than about 1.0 psi per linear foot of height within the cavern, and less than about 4.0 psi per linear foot of height within the cavern.

Storage vessel, system and method for storing compressed gas are provided. A storage vessel for storing compressed gas comprises a wellbore provided in the subsurface; a casing placed within the wellbore and cemented to the formation, the casing defining a volumetric space within the wellbore for storing the compressed gas; and at least one flow regulator sealed at a top end of the casing for selectively injecting the compressed gas into the space or discharging the compressed gas from the space, wherein the wellbore has a volumetric capacity of at least 20 m3, and wherein the compressed gas has a pressure of at least 5 MPa.

Storage vessel, system and method for storing compressed gas are provided. A storage vessel for storing compressed gas comprises a wellbore provided in the subsurface; a casing placed within the wellbore and cemented to the formation, the casing defining a volumetric space within the wellbore for storing the compressed gas; and at least one flow regulator sealed at a top end of the casing for selectively injecting the compressed gas into the space or discharging the compressed gas from the space, wherein the wellbore has a volumetric capacity of at least 20 m3, and wherein the compressed gas has a pressure of at least 5 MPa.

A system and method of creating, operating and maintaining a hydrocarbon storage facility in a salt cavern within an underground salt deposit. The system is portable and can be transported to areas near different well heads. The portability also enables adjacent well heads to be worked in succession to create a large storage cavern by interlinking a series of smaller caverns. This formation processes ensures that a storage cavern can be isolated within the confines of a salt deposit. Using the same portable equipment, the system can be configured to form a salt cavern, displace stored material out of a salt cavern, and repair or maintain a salt cavern well.

The present invention discloses an I-shaped water-retaining dam for an underground reservoir in a coal mine. The I-shaped water-retaining dam is located between coal pillar dams to isolate an underground reservoir from a corresponding coal roadway. The I-shaped water-retaining dam includes an upper flange plate, a web plate, and a lower flange plate from top to bottom, where a vertical face of a dam body is of an I shape; the upper flange plate extends into a roadway roof; two ends of the web plate are embedded into the coal pillar dams; and the lower flange plate extends into a floor. The I-shaped water-retaining dam is located in an underground coal roadway, and bears complex surrounding rock stress. The present invention effectively overcomes water seepage of a weak part at an upper part of a conventional I-shaped water-retaining dam.

Storage vessel, system and method for storing compressed gas are provided. A storage vessel for storing compressed gas comprises a wellbore provided in the subsurface; a casing placed within the wellbore and cemented to the formation, the casing defining a volumetric space within the wellbore for storing the compressed gas; and at least one flow regulator sealed at a top end of the casing for selectively injecting the compressed gas into the space or discharging the compressed gas from the space, wherein the wellbore has a volumetric capacity of at least 20 m3, and wherein the compressed gas has a pressure of at least 5 MPa.

Storage vessel, system and method for storing compressed gas are provided. A storage vessel for storing compressed gas comprises a wellbore provided in the subsurface; a casing placed within the wellbore and cemented to the formation, the casing defining a volumetric space within the wellbore for storing the compressed gas; and at least one flow regulator sealed at a top end of the casing for selectively injecting the compressed gas into the space or discharging the compressed gas from the space, wherein the wellbore has a volumetric capacity of at least 20 m3, and wherein the compressed gas has a pressure of at least 5 MPa.

The disclosure provides a liquid taking device and a liquid taking method. The liquid taking device comprises a liquid taking bottle, a heavy ball and liquid taking ropes. The liquid taking bottle has a first mouth and a bottom opposite to the first mouth. The heavy ball is arranged in the liquid taking bottle. The liquid taking device can be controlled to reach different depths under the ground by the action of two liquid ropes. When the first mouth of the bottle is placed facing downward, the heavy ball blocks the first mouth of the bottle under its own gravity to prevent liquid leakage; when the first mouth of the bottle is turned upwards under the action of the liquid taking rope, the heavy ball falls onto the bottom of the bottle, such that an external liquid can flow into the liquid taking device, which has a good practical utility.

The disclosure provides a liquid taking device and a liquid taking method. The liquid taking device comprises a liquid taking bottle, a heavy ball and liquid taking ropes. The liquid taking bottle has a first mouth and a bottom opposite to the first mouth. The heavy ball is arranged in the liquid taking bottle. The liquid taking device can be controlled to reach different depths under the ground by the action of two liquid ropes. When the first mouth of the bottle is placed facing downward, the heavy ball blocks the first mouth of the bottle under its own gravity to prevent liquid leakage; when the first mouth of the bottle is turned upwards under the action of the liquid taking rope, the heavy ball falls onto the bottom of the bottle, such that an external liquid can flow into the liquid taking device, which has a good practical utility.