The present disclosure generally relates to a combined multicoupler for connecting a tool to a top drive. The combined multicoupler includes a load frame comprising a frame body having a load shoulder, and a side door coupled to the frame body. The side door opens from the frame body to allow a tool sliding horizontally into the load shoulder, and the side door closes to lock the tool in the load frame. The combined multicoupler further comprises a drive stem movably coupled to the load frame, wherein the drive stem moves vertically to connect and disconnect with the tool in the load frame.

A directional casing drilling system includes a casing string, a drilling rig and a retrievable Bottom Hole Assembly (BHA). The drilling rig includes a casing drive for rotating the casing string in the borehole, a control system for controlling the casing drive, and a mud pump for pumping a continuous flow of drilling mud into the casing string. The BHA includes a torque transfer section, with which it is secured in the casing string, and a drill bit section held in a drilling position in the torque transfer section. It further includes a mud drive that rotates the drilling position of the drill bit section about the longitudinal axis of the torque transfer section, and a communicating device for communicating the orientation of the drill bit to the control system. The BHA is steered by adjusting the rotational speed of the casing string.

A sensing system including in-ground sensors not requiring battery power. A thermoelectric generator sensor rod includes an upper thermal contact and a lower thermal contact at or near its two ends. When the thermoelectric generator sensor rod is buried in the ground with one end buried more deeply than the other, a temperature gradient in the soil produces a temperature difference between the upper thermal contact and the lower thermal contact. The upper thermal contact and the lower thermal contact are thermally connected to a thermoelectric generator, e.g., by heat pipes or thermally conductive rods. Electrical power generated by the thermoelectric generator powers sensors for monitoring conditions in the ground, and circuitry for transmitting sensor data to a central data processing system.

The present invention comprises an arrangement in a borehole. Such an arrangement comprises two tubes, an outer tube and an inner tube being arranged within each other having essentially parallel longitudinal axes. Said outer and inner tubes are connected to incoming and outgoing tubes respectively. The cross sectional area of the inner tube is less than half of the cross sectional area of the outer tube, whereby the outer tube and/or the incoming and outgoing tubes arranged in the borehole are insulated until they reach below a freezing depth of the surrounding media. Said the inner tube is also arranged to end before reaching the bottom end of the outer tube when inserted in the borehole, thus forming a fluid passage between the both tubes at the bottom end of said borehole.

The present invention is a method of simulating fluid flows in an underground formation comprising a fracture network. A porosity model is constructed, comprising a first medium representative of an unfractured matrix, a second medium representative of fractures oriented in a first direction and a third medium representative of fractures oriented in a second direction orthogonal to the first direction. From at least the porosity model, flow parameters of a grid representation of the formation are determined, which include conduction and convection transmissibilities between two neighboring cells for the second and third media, as well as mass and energy exchanges by convection and conduction between each medium taken two by two for a single cell. Flows in the formation are simulated by f a flow simulator implementing the porosity model.

The present disclosure provides a comprehensive utilization method and test equipment for surface water, a goaf and geothermal energy in a coal mining subsidence area. The method comprises the following steps: determining a geothermal water collection area, arranging heat energy exchange equipment in a main roadway, and arranging a geothermal water extraction system, wherein the geothermal water extraction system comprises geothermal wells, extraction pipelines and tail water reinjection pipelines, the extraction pipelines are connected with the heat energy exchange equipment, and the tail water reinjection pipelines are connected with a water outlet of the heat energy exchange equipment; arranging a water channel on the surface, and arranging a drainage system on a subsidence trough to guide surface water to flow underground; and controlling directional and ordered flow of surface water through the coal mining subsidence area formed by ground mining to achieve sustainable mining of underground water.

The disclosed technology includes methods of extracting geothermal energy, generally comprising the steps of: insertion of a thermal mass into a Heat Absorption Zone, absorbing heat in thermal mass, raising the thermal mass to a Heat Transfer Zone, and transferring the heat from the thermal mass. The acquired heat can be used to generate electricity or to drive an industrial process. The thermal mass can have internal chambers containing a liquid such as molten salt, and can also have structures facilitating heat exchange using a thermal exchange fluid, such as a gas or a glycol-based fluid. In some embodiments, two thermal masses are used as counterweights, reducing the energy consumed in bringing the heat in the thermal masses to the surface. In other embodiments, solid or molten salt can be directly supplied to a well shaft to acquire geothermal heat and returned to the surface in a closed loop system.

A composite particle that incorporates a material and is designed to undergo a reaction and/or mechanical or chemical change with the environment to increase in volume. The composite particle can be combined with a constraining matrix to create an expandable particle upon reaction. These particles can be used in stimulating wells, including oil and gas reservoirs.

A system and method provide integrated carbon-negative, geothermal-based, energy generation and storage. The embodiments produce dispatchable electricity at grid-scale by storing excess energy from the grid and generating its own energy. The excess energy may be taken from solar and wind sources. In one aspect, the subject technology is energy storage, energy generation, carbon utilization and sequestration, all in one. The technology has very high round-trip efficiency of storing energy and is carbon-negative which makes it far more sustainable than any competing energy storage technology.

A wellhead is provided. The wellhead comprises a high pressure wellhead housing; a casing hanger assembly located within the high pressure wellhead housing; and a casing supported on the casing hanger assembly. The casing hanger assembly is arranged so that the casing is able to move relative to the high pressure wellhead housing. This may be to accommodate well growth experienced by the wellhead during use.