Abstract: For pulsed injection of liquids into the ground, the tool has a rotating cylinder, having through-slots. The tool has an insert, which is pressed against the rotating cylinder. As the cylinder rotates, the slots in the rotor cover/uncover the slots in the insert, creating the required pulses. By suitably shaping the slots, the pulses can have a fast rise-time from closed to open. The insert is shaped to minimize flow interference.

Abstract: When injecting liquids into the ground, imposing pulses on the injected liquid is effective to increase penetration and saturation of the ground. Imposing suckback onto the pulses is effective to make the liquid in the ground behave as a coherent unitary body, surging out and back each pulse, and to super-saturate the ground. The tool includes a suckback-chamber, which is timed to open to the ground formation just as the pulse-valve closes. A biasser (e.g a spring) drives the chamber open and sucks in some of the liquid from the ground. The chamber is then emptied, back to the ground, by the rising pressure as the pulsing tool is recharged. The suckback-chamber can be added to any type of pulsing tool.

Abstract: For injecting e.g. water into ground formation around a borehole, and for superimposing pulses onto the outflow of the injected water, it is important that the pulses have a rapid rise-time. A piston is connected to a pulse-valve of the tool. A bias spring urges the piston towards its closed position. The piston is urged towards the open position by a differential PDAF between the supplied accumulator-pressure and the in-ground formation-pressure. When the pulse-valve is open, the PDAF is falling, until the force of the spring closes the pulse-valve. Then the PDAF rises, but now the PDAF acts over only a small area of the piston. When the PDAF is high enough to ease the pulse-valve open, suddenly the whole area of the piston is exposed to the PDAF, whereby the pulse-valve opens violently.

Abstract: Applying pulses to liquid being injected into wells makes the ground/liquid formation more homogenous, and more penetrative. A system for automatically creating the pulses is described, in which a piston is acted upon by the pressure differential (PDAF) between the supplied accumulator pressure and the formation pressure. The changing levels of the PDAF as the pulse-valve opens (and the PDAF falls) and as the pulse-valve closes (and the PDAF rises) are harnessed to actuate an inhibitor that restrain movement of the valve-piston, and delays opening and/or closing of the pulse-valve. The pulse-valve is engineered to open explosively, and thus create penetrative porosity-waves in the formation. The system includes a pressurized-gas accumulator, and injection-check-valve which can maintain pulsing even when the ground is not saturated, and the static injector, which allows non-pulsed injection only when the ground is non-saturated.

Abstract: During a surge-pulsing operation in a borehole (e.g an oil-well undergoing remediation) liquid is stored under pressure upstream of a valve, and then released through the valve suddenly enough to create a seismic wave, which propagates into the formation around the borehole, and assists the surge-pulsing to improve the conductivity and liquid-injectability of the formation. The downhole valve achieves the rapid-opening requirement by virtue of its geometrical layout, as dictated by the strictures of the downhole environment.

Abstract: When injecting liquids into the ground, imposing pulses on the injected liquid is effective to increase penetration and saturation of the ground. Imposing suckback onto the pulses is effective to make the liquid in the ground behave as a coherent unitary body, surging out and back each pulse, and to super-saturate the ground. The tool includes a suckback-chamber, which is timed to open to the ground formation just as the pulse-valve closes. A biasser (e.g a spring) drives the chamber open and sucks in some of the liquid from the ground. The chamber is then emptied, back to the ground, by the rising pressure as the pulsing tool is recharged. The suckback-chamber can be added to any type of pulsing tool.

Abstract: A method is taught for applying vacuum pulses to enhance multiphase vacuum extraction of vapours and liquids from contaminated subsurface wells. The method involves first initiating continuous multiphase vacuum extraction from the subsurface well. Then one or more short vacuum pulses are imparted to the subsurface environment, to momentarily interrupt flow of vapours and liquids in the subsurface well. Time is allowed for a vacuum to build up in the extraction apparatus; and then the vacuum build up is rapidly released to momentarily increase velocity of vapours and liquids being extracted from the subsurface well. A device is further taught for imparting vacuum pulses to enhance multiphase extraction from contaminated subsurface wells, comprising a vacuum pulse tool having an inlet in fluid communication with the subsurface well and an outlet and one or more multiphase extraction vacuum pumps, connected to the outlet of the vacuum pulse tool.

Abstract: Applying pulses to liquid being injected into wells makes the ground/liquid formation more homogenous, and more penetrative. A system for automatically creating the pulses is described, in which a piston is acted upon by the pressure differential (PDAF) between the supplied accumulator pressure and the formation pressure. The changing levels of the PDAF as the pulse-valve opens (and the PDAF falls) and as the pulse-valve closes (and the PDAF rises) are harnessed to actuate an inhibitor that restrain movement of the valve-piston, and delays opening and/or closing of the pulse-valve. The pulse-valve is engineered to open explosively, and thus create penetrative porosity-waves in the formation. The system includes a pressurized-gas accumulator, and injection-check-valve which can maintain pulsing even when the ground is not saturated, and the static injector, which allows non-pulsed injection only when the ground is non-saturated.

Abstract: For injecting e.g. water into ground formation around a borehole, and for superimposing pulses onto the outflow of the injected water, it is important that the pulses have a rapid rise-time. A piston is connected to a pulse-valve of the tool. A bias spring urges the piston towards its closed position. The piston is urged towards the open position by a differential PDAF between the supplied accumulator-pressure and the in-ground formation-pressure. When the pulse-valve is open, the PDAF is falling, until the force of the spring closes the pulse-valve. Then the PDAF rises, but now the PDAF acts over only a small area of the piston. When the PDAF is high enough to ease the pulse-valve open, suddenly the whole area of the piston is exposed to the PDAF, whereby the pulse-valve opens violently.

Abstract: For pulsed injection of liquids into the ground, the tool has a rotating cylinder, having through-slots. The tool has an insert, which is pressed against the rotating cylinder. As the cylinder rotates, the slots in the rotor cover/uncover the slots in the insert, creating the required pulses. By suitably shaping the slots, the pulses can have a fast rise-time from closed to open. The insert is shaped to minimize flow interference.

Abstract: For extracting a liquid (such as oil) from a porous medium, the liquid is subjected to pulses that propagate through the liquid flowing through the pores of the medium. The pulses cause momentary surges in the velocity of the liquid, which keeps the pores open. The pulses can be generated in the production well, or in a separate excitation well. If the pulses travel with the liquid, the velocity of travel of the liquid through the pores can be increased. The solid matrix is kept stationary, and the pulses move through the liquid. The pulses in the liquid can be generated directly in the liquid, or indirectly in the liquid via a localized area of the solid matrix.

Abstract: During a surge-pulsing operation in a borehole (e.g an oil-well undergoing remediation) liquid is stored under pressure upstream of a valve, and then released through the valve suddenly enough to create a seismic wave, which propagates into the formation around the borehole, and assists the surge-pulsing to improve the conductivity and liquid-injectability of the formation. The downhole valve achieves the rapid-opening requirement by virtue of its geometrical layout, as dictated by the strictures of the downhole environment.

Abstract: For extracting a liquid (such as oil) from a porous medium, the liquid is subjected to pulses that propagate through the liquid flowing through the pores of the medium. The pulses cause momentary surges in the velocity of the liquid, which keeps the pores open. The pulses can be generated in the production well, or in a separate excitation well. If the pulses travel with the liquid, the velocity of travel of the liquid through the pores can be increased. The solid matrix is kept stationary, and the pulses move through the liquid. The pulses in the liquid can be generated directly in the liquid, or indirectly in the liquid via a localized area of the solid matrix.

Abstract: For extracting a liquid (such as oil) from a porous medium, the liquid is subjected to pulses that propagate through the liquid flowing through the pores of the medium. The pulses cause momentary surges in the velocity of the liquid, which keeps the pores open. The pulses can be generated in the production well, or in a separate excitation well. If the pulses travel with the liquid, the velocity of travel of the liquid through the pores can be increased. The solid matrix is kept stationary, and the pulses move through the liquid. The pulses in the liquid can be generated directly in the liquid, or indirectly in the liquid via a localised area of the solid matrix.

Abstract: For extracting a liquid (such as oil) from a porous medium, the liquid is subjected to pulses that propagate through the liquid flowing through the pores of the medium. The pulses cause momentary surges in the velocity of the liquid, which keeps the pores open. The pulses can be generated in the production well, or in a separate excitation well. If the pulses travel with the liquid, the velocity of travel of the liquid through the pores can be increased. The solid matrix is kept stationary, and the pulses move through the liquid. The pulses in the liquid can be generated directly in the liquid, or indirectly in the liquid via a localized area of the solid matrix.

Abstract: For extracting a liquid (such as oil) from a porous medium, the liquid is subjected to pulses that propagate through the liquid flowing through the pores of the medium. The pulses cause momentary surges in the velocity of the liquid, which keeps the pores open. The pulses can be generated in the production well, or in a separate excitation well. If the pulses travel with the liquid, the velocity of travel of the liquid through the pores can be increased. The solid matrix is kept stationary, and the pulses move through the liquid. The pulses in the liquid can be generated directly in the liquid, or indirectly in the liquid via a localized area of the solid matrix.

Abstract: For extracting a liquid (such as oil) from a porous medium, the liquid is subjected to pulses that propagate through the liquid flowing through the pores of the medium. The pulses cause momentary surges in the velocity of the liquid, which keeps the pores open. The pulses can be generated in the production well, or in a separate excitation well. If the pulses travel with the liquid, the velocity of travel of the liquid through the pores can be increased. The solid matrix is kept stationary, and the pulses move through the liquid. The pulses in the liquid can be generated directly in the liquid, or indirectly in the liquid via a localised area of the solid matrix.