Abstract: A method of using an everting borehole liner to perform fluid conductivity measurements in materials surrounding a pipe, tube, or conduit, such as a borehole below the surface of the Earth. A flexible liner is everted (turned inside out) into the borehole with an internal pressurized fluid. As the liner displaces the ambient fluid in the borehole into the surrounding formation, the rate of descent of the liner is recorded. As the impermeable liner covers the flow paths in the wall of the hole, the descent rate slows. From the measured descent rate, the flow rates out discrete sections of the borehole are determined.

Abstract: A coalbed methane borehole pipe liner perforation system comprises a plastic pipe punch that slips down inside a coalbed methane production borehole lined with a non-perforated plastic pipe. A ground-penetrating radar is used inside the plastic-pipe lined borehole to determine which sections of the pipe are in contact with groundwater. The punch is then operated along the length of the plastic-pipe lined borehole to perforate it for methane-gas collection wherever such groundwater is not present. A radar survey to determine groundwater contact can be made simultaneously in combination with the punching of liner pipe perforations, or earlier in a separate operation.

Abstract: System and methods for transmitting and receiving electromagnetic pulses through a geological formation. A preferably programmable transmitter having an all-digital portion in a preferred embodiment may be operated at frequencies below 1 MHz without loss of target resolution by transmitting and over sampling received long PN codes. A gated and stored portion of the received signal may be correlated with the PN code to determine distances of interfaces within the geological formation, such as the distance of a water interfaces from a wellbore. The received signal is oversampled preferably at rates such as five to fifty times as high as a carrier frequency. In one method of the invention, an oil well with multiple production zones may be kept in production by detecting an approaching water front in one of the production zones and shutting down that particular production zone thereby permitting the remaining production zones to continue operating.

Abstract: For collecting data from a water well, down-hole sensors are housed in modules. The modules are arranged to be screwed together in-line to form a vertical string. Mechanically, the modules are secured to each other only by the screw connection. Data is transmitted to the surface on a 2-wire cable, there being no other electrical connection between the modules and the surface. The modules are connected in multi-drop configuration to the 2-wire cable. Data is transmitted using time-division multiplexing.

Abstract: An apparatus for use in circulating cement in a casing in a wellbore is described having a first component such as a sensor disposed on the casing and a second component such as a detectable device disposed at a fluid interface formed between the cement and a fluid. The sensor may be a sensor coil mounted on the perimeter of the lower end of the casing, while the detectable device may be a transponder capable of emitting Radio Frequency Identification signals to the sensor to signal its arrival at the lower end of the casing. The transponder may be encased in a protective covering. Also described is a method of cementing a casing utilizing a first component such as a sensor disposed on the casing and a second component such as a detectable device disposed in the cement.

Abstract: A monitoring system for monitoring resources such as water in a bore having an air column extending from a wellhead to a surface level and a resource column extending from the surface level to an extraction inlet includes a sensor unit and a base unit. The sensor unit includes a sensor mounted within the bore and including a transmitting unit for transmitting at least a single sound pulse formed of a pulsed sinusoidal waveform into the bore and a receiving unit for receiving a return signal representing the single sound pulse reflected from the water surface level. The base unit uses the measured round trip time to determine an air column length from the sensor to the water surface level and a water column length from the water surface level to the extraction inlet and, from a cross sectional area of the bore, a water resource value representing a volume of water contained between the water surface level and the extraction inlet.

Abstract: A controllable gas-lift well having controllable gas-lift valves and sensors for detecting flow regime is provided. The well uses production tubing and casing to communicate with and power the controllable valve from the surface. A signal impedance apparatus in the form of induction chokes at the surface and downhole electrically isolate the tubing from the casing. A high band-width, adaptable spread spectrum communication system is used to communicate between the controllable valve and the surface. Sensors, such as pressure, temperature, and acoustic sensors, may be provided downhole to more accurately assess downhole conditions and in particular, the flow regime of the fluid within the tubing. Operating conditions, such as gas injection rate, back pressure on the tubing, and position of downhole controllable valves are varied depending on flow regime, downhole conditions, oil production, gas usage and availability, to optimize production.

Abstract: A system to determine the mixture of fluids in the deviated section of a wellbore comprising at least one distributed temperature sensor adapted to measure the temperature profile along at least two levels of a vertical axis of the deviated section. Each distributed temperature sensor can be a fiber optic line functionally connected to a light source that may utilize optical time domain reflectometry to measure the temperature profile along the length of the fiber line. The temperature profiles at different positions along the vertical axis of the deviated wellbore enables the determination of the cross-sectional distribution of fluids flowing along the deviated section. Together with the fluid velocity of each of the fluids flowing along the deviated section, the cross-sectional fluid distribution enables the calculation of the flow rates of each of the fluids. The system may also be used in conjunction with a pipeline, such as a subsea pipeline, to determine the flow rates of fluids flowing therethrough.

Abstract: A method of using an everting borehole liner to perform fluid conductivity measurements in materials surrounding a pipe, tube, or conduit, such as a borehole below the surface of the Earth. A flexible liner is everted (turned inside out) into the borehole with an internal pressurized fluid. As the liner displaces the ambient fluid in the borehole into the surrounding formation, the rate of descent of the liner is recorded. As the impermeable liner covers the flow paths in the wall of the hole, the descent rate slows. From the measured descent rate, the flow rates out discrete sections of the borehole are determined.

Abstract: A method of producing gas through liquid level detection in oil or gas wells uses various types of artificial lift systems that include sub surface gas lift, beam pumps, progressive cavity pump and submersible pumps. The artificial lift systems are controlled in response to a known liquid level within the well bore to prevent the well from pumping off and damaging the artificial lift system or from reducing the liquid level in the well bore to an unnecessarily low level to thereby increase the energy required by the artificial lift system to remove the liquid from the well bore.

Abstract: The main problem area this invention is solving, is concerning reservoirs containing gas with to low well-head pressure. It is therefore desirable to increase the well-head pressure by applying downhole pumps, however this is not possible if gas is present. The core idea in this present invention, is to place a pump (5) in a “bath” of oil (14), in which oil “bath” (14) makes a gas seal (11), assuring the pump only to be imposed to oil without gas. Oil and gas from the reservoir (1) flows trough perforations (2), into a ring-space (3). This creates a significantly pressure drop of the mixture, in which creates turbulence so the gas content will separate from the oil. The pressure drop is regulated by the gas pressure valve (4).

Abstract: A method and apparatus that allows communications of electrical power and signaling from downhole component to another downhole component employs an inductive coupler assembly. In one arrangement, one portion of the inductive coupler assembly is attached to a production tubing section and the other portion of the inductive coupler assembly is attached to a casing or other liner section. The production tubing inductive coupler portion is electrically connected to a cable over which electrical power and signals may be transmitted. Such power and signals are magnetically coupled to the inductive coupler portion in the casing or liner section and communicated to various electrical devices mounted outside the casing or liner section. In other arrangements, inductive coupler assemblies may be used to couple electrical power and signals from the main bore to components in lateral branches of a multilateral well.

Abstract: A method and apparatus for remediation of non-aqueous phase liquids (NAPL), including the use of a prior art hydrophobic adsorption system including a continuous loop of adsorptive material, with a weighted pulley on the free end of the loop to allow for the loop to be placed within a well being deeper than it is wide.

Abstract: System and methods are disclosed for transmitting and receiving electromagnetic pulses through a geological formation. A preferably programmable transmitter having an all-digital portion in a preferred embodiment may be operated at frequencies below 1 MHz without loss of target resolution by transmitting and over sampling received long PN codes. A gated and stored portion of the received signal may be correlated with the PN code to determine distances of interfaces within the geological formation, such as the distance of a water interfaces from a wellbore. The received signal is oversampled preferably at rates such as five to fifty times as high as a carrier frequency. In one method of the invention, an oil well with multiple production zones may be kept in production by detecting an approaching water front in one of the production zones and shutting down that particular production zone thereby permitting the remaining production zones to continue operating.

Abstract: Plunger lift operations are difficult to optimize due to lack of knowledge of tubing pressure, casing pressure, bottom-hole pressure, liquid accumulation in the tubing and location of the plunger. Monitoring the plunger position in the tubing helps the operator (or controller) to optimize the removal of liquids and gas from the well. The plunger position can be tracked from the surface by monitoring acoustic signals generated as the plunger falls down the tubing. When the plunger passes by a tubing collar recess, an acoustic pulse is generated that travels up the gas within the tubing. The acoustic pulses are monitored at the surface, and are converted to an electrical signal by a microphone. The signal is digitized, and the digitized data is stored in a computer. Software processes this data along with the tubing and casing pressure data to display plunger depth, plunger velocity and well pressures vs. time.

Abstract: A method of producing gas through liquid level detection in oil or gas wells uses various types of artificial lift systems that include sub surface gas lift, beam pumps, progressive cavity pump and submersible pumps. The artificial lift systems are controlled in response to a known liquid level within the well bore to prevent the well from pumping off and damaging the artificial lift system or from reducing the liquid level in the well bore to an unnecessarily low level to thereby increase the energy required by the artificial lift system to remove the liquid from the well bore.

Abstract: A monitoring system and method for monitoring a predetermined set of physical characteristics associated with a structure using the monitoring system. The system is distributed in the structure and comprises a distributed optical sensing device (30), further comprising a fiber optic cable (20, 22); a light source (18a) operatively in communication with the fiber optic cable (20, 22); a light detection device (18b), operatively in communication with the fiber optic cable (20, 22), for measuring the light received at the light detection device (18b) from the fiber optic cable (20, 22); and a data processor (18) capable of using the light measured to calculate a predetermined set of physical parameters describing the predetermined set of physical characteristics.

Abstract: An apparatus and method for collecting a sample from a low-yield well or perched aquifer includes a pump and a controller responsive to water level sensors for filling a sample reservoir. The controller activates the pump to fill the reservoir when the water level in the well reaches a high level as indicated by the sensor. The controller deactivates the pump when the water level reaches a lower level as indicated by the sensors. The pump continuously activates and deactivates the pump until the sample reservoir is filled with a desired volume, as indicated by a reservoir sensor. At the beginning of each activation cycle, the controller optionally can select to purge an initial quantity of water prior to filling the sample reservoir. The reservoir can be substantially devoid of air and the pump is a low volumetric flow rate pump. Both the pump and the reservoir can be located either inside or outside the well.

Abstract: The present invention provides an artificial lift apparatus that monitors the conditions in and around a well and makes automated adjustments based upon those conditions. In one aspect, the invention includes a pump for disposal at a lower end of a tubing string in a cased wellbore. A pressure sensor in the wellbore adjacent the pump measures fluid pressure of fluid collecting in the wellbore. Another pressure sensor disposed in the upper end of the wellbore measures pressure created by compressed gas above the fluid column and a controller receives the information and calculates the true height of fluid in the wellbore. Another sensor disposed in the lower end the tubing string measures fluid pressure in the tubing string and transmits that information to the controller. The controller compares the signals for the sensors and makes adjustments based upon a relationship between the measurements and preprogrammed information about the wellbore and the formation pressure therearound.

Abstract: A system and method for closing a subterranean valve (22) to terminate a reverse cementing operation is disclosed. The system comprises an interrogator (44) operably associated with the valve (22) that detects at least one detectable member (52) that is associated with an interface (50) between a first fluid (48) and a cement composition (54) that is pumped through an annulus (26) between a pipe string (20) and a wellbore (18). The detectable member (50) is detectable by the interrogator (44) when the detectable member (50) comes within communicative proximity with the interrogator (44). Once the interrogator (44) detects the detectable member (50), the interrogator (44) sends a signal indicating it is time to close the valve (22), thereby terminating the cementing process and allowing the cement (54) to set in the annulus (26) into a hard, substantially impermeable mass.

Abstract: A method of producing gas through liquid level detection in oil or gas wells uses various types of artificial lift systems that include sub surface gas lift, beam pumps, progressive cavity pump and submersible pumps. The artificial lift systems are controlled in response to a known liquid level within the well bore to prevent the well from pumping off and damaging the artificial lift system or from reducing the liquid level in the well bore to an unnecessarily low level to thereby increase the energy required by the artificial lift system to remove the liquid from the well bore.

Abstract: The present invention relates generally to the treating of wells, and more particularly to a method and device that are capable of detecting the position of a fluid interface so that a well treatment can be placed with greater along hole depth precision in a given hydrocarbon producing well than previously. More particularly, an embodiment of the invention includes a method for accurately placing a well treatment fluid in a well, comprising: pumping a first fluid into a first part of the well until an interface is formed between the first fluid and a second fluid; extracting information regarding at least one fluid property of the first and second fluids with first and second to sensors positioned in the first and second fluids respectively; and exchanging information between the first and second sensors and a telemetry unit.

Abstract: This is a high-efficiency item of equipment, for example for a well bottom for separating out gas from a liquid/gas mixture, based on the effects of flows of the cascade and segregated types. It consists basically of a sedimentation vessel whose lateral surface has holes in the upper portion, enclosing (i) a discharge pump, (ii) a suction pipe and (iii) the lower end of a production tubing. The vessel contains helicoidal surfaces for achieving segregated-type flow. A significant part of separation takes place above the level of the separator, in a medium in which there is a predominance of gas and the flow is in the form of a cascade.

Abstract: An apparatus and method for collecting a sample from a low-yield well or perched aquifer includes a pump and a controller responsive to water level sensors for filling a sample reservoir. The controller activates the pump to fill the reservoir when the water level in the well reaches a high level as indicated by the sensor. The controller deactivates the pump when the water level reaches a lower level as indicated by the sensors. The pump continuously activates and deactivates the pump until the sample reservoir is filled with a desired volume, as indicated by a reservoir sensor. At the beginning of each activation cycle, the controller optionally can select to purge an initial quantity of water prior to filling the sample reservoir. The reservoir can be substantially devoid of air and the pump is a low volumetric flow rate pump. Both the pump and the reservoir can be located either inside or outside the well.

Abstract: A device (10) for collecting fluid samples from a subsurface (100), injecting fluids into a subsurface and measuring the hydrostatic pressure of groundwater in a subsurface is described. The device includes an outer tube (12) with a center bore (12D) and openings (12E) at one end (12B) and a rigid inner rod (18) configured to be telescopingly inserted into the center bore of the outer tube. The inner rod provides support and prevents damage to the outer tube during insertion into the subsurface. The device is inserted into the subsurface until the openings in the outer tube are adjacent the testing area. The inner rod is then removed from the outer tube. To collect fluid samples, the samples are retrieved from the fluid which has moved from the subsurface through the openings to the center bore of the outer tube. To inject fluid into the subsurface, the fluid is injected into the center bore and flows through the openings to the subsurface.

Abstract: A hydrocarbon reservoir undergoing secondary recovery is subject to a first and then at least a second gravity gradient survey in which a gravity gradiometer takes gradient measurements on the surface above the reservoir to define successive data sets. The differences between the first and subsequent gravity gradient survey yields information as to sub-surface density changes consequent to displacement of the hydrocarbon and the replacement thereof by the driveout fluid including the position, morphology, and velocity of the interface between the hydrocarbon to be recovered and the driveout fluid.

Abstract: A method and apparatus for monitoring the fluid level in a well bore to limit fluid drawdown in the well bore to a maximum set level. The user first determines the static water level in the well bore by lowering a sensor into the well bore. The sensor is configured to sense when it makes contact with water, so that the user can be made aware that the sensor has reached the static water level. The user then lowers the sensor to a maximum desired drawdown level. The sensor is then set to sense when it loses contact with the water. The sensor is then monitored to determine if the fluid had has dropped below the maximum desired drawdown level, and an audible and/or visual alarm alerts the user whenever the maximum desired drawdown level is exceeded.

Abstract: A method of using a variety of sonic transmissions is utilized to determine fluid level in a well. It is known that wells replenish fluid at different rates even in the same formation or well field. Maximum production at minimum pumping cost is achieved for a given well.

Abstract: A system for reservoir control. The system allows segregated production of fluids, e.g. water and oil, to control the fluid-fluid interface. Downhole sensors are utilized in providing data about the location of the interface. This permits the proactive monitoring and control of the interface prior to unwanted intermingling of fluids, e.g. oil and water, during production.

Abstract: Plunger lift operations are difficult to optimize due to lack of knowledge of tubing pressure, casing pressure, bottom-hole pressure, liquid accumulation in the tubing and location of the plunger. Monitoring the plunger position in the tubing helps the operator (or controller) to optimize the removal of liquids and gas from the well. The plunger position can be tracked from the surface by monitoring acoustic signals generated as the plunger falls down the tubing. When the plunger passes by a tubing collar recess, an acoustic pulse is generated that travels up the gas within the tubing. The acoustic pulses are monitored at the surface, and are converted to an electrical signal by a microphone. The signal is digitized, and the digitized data is stored in a computer. Software processes this data along with the tubing and casing pressure data to display plunger depth, plunger velocity and well pressures vs. time.

Abstract: System and method for controlling fluid flows in one or more oil and/or gas wells in a geological formation, the wells each comprising a production tube, the formation containing a water-containing volume with a higher water level, comprising: one or more measuring devices, each mounted in relation to a chosen zone of a well for measuring the distance to the water level in the zone, one or more valve devices comprised in the production tubes for regulating the fluid flow from the surrounding formation to the production tube, one or more control units connected to each of the valves for regulating then on the basis of the measured distance or distances.

Abstract: A well monitoring apparatus for burial in the ground to sample and monitor subsurface water having a cylindrical bailer unit with an internal reservoir chamber for collection of samples communicated thereto from outside the bailer. A pressurization system allows for selected pressurization of the chamber from a remote location to transmit fluid therform to a remote location for inspection. The bailer may be buried separately or attached to the lower end of a conventional well casing.

Abstract: A method, of logging a borehole, for use in a cased oil well for detecting the gas/oil or water/oil contact in a hydrocarbon reservoir, using a neutron capture technique to detect one or more properties of fluid includes comparing the count rates from two or more radiation detectors spaced at respective first and second distances from an isotopic source of continuous neutron radiation. The contact detection criteria are arranged to be substantially independent of borehole fluid characteristics.

Abstract: An improved method to detect water influx using video monitoring of a cased wellbore is disclosed. A wireline well tool having a video camera and a light source is lowered into a selected borehole interval where water influx is suspected. The borehole fluid over the selected interval is displaced and replaced with either a water transparent mixture containing a viscosifying agent, a coloring agent and/or sufficient salt to increase mixture density; or a transparent water insoluble solvent. By use of either of these displacement fluids, the quality of video monitoring over the selected borehole interval for water influx, is enhanced.

Abstract: An apparatus for improved detection of underground well kicks, preferably comprising a first acoustic sensor mounted on the top drive of a drilling rig in acoustic contact with a liquid level within a drill string which is generally located within a wellbore, a second acoustic sensor in a trip tank connected to the wellbore, and a drawworks position indicator. The acoustic sensors detect signals reflected from liquid level interfaces allowing calculation of injected liquid volumes from the trip tank into the wellbore and liquid volume changes within the drill string. The drawworks sensor allows calculation of tubular volumes removed from the wellbore over time. Comparison or totaling of calculated volumes allows early detection of unwanted fluid fluxes between the wellbore and an underground formation.

Abstract: A controllable gas-lift well having controllable gas-lift valves and sensors for detecting flow regime is provided. The well uses production tubing and casing to communicate with and power the controllable valve from the surface. A signal impedance apparatus in the form of induction chokes at the surface and downhole electrically isolate the tubing from the casing. A high band-width, adaptable spread spectrum communication system is used to communicate between the controllable valve and the surface. Sensors, such as pressure, temperature, and acoustic sensors, may be provided downhole to more accurately assess downhole conditions and in particular, the flow regime of the fluid within the tubing. Operating conditions, such as gas injection rate, back pressure on the tubing, and position of downhole controllable valves are varied depending on flow regime, downhole conditions, oil production, gas usage and availability, to optimize production.

Abstract: An intermittent gas lift well pumping system containing an accumulator, a gas line, a liquid discharge line, and a battery operated controller. By using one or more constrictions in the gas line and acoustical techniques, accurate liquid level is determined in the pumping system for optimum production. Bypasses are connected between the gas line and the liquid discharge line. Each contains a valve that opens at a preset absolute pressure in the gas line, an orifice, and a one-way valve. The bypasses are strategically placed to prevent overloading of the system. A liquid slug sensor on the upper end of the liquid discharge line and a rabbit in this line enables optimum production and gas conservation.

Abstract: Initially, signals relating to well bore fluids that are generated from sensors in presently available down-hole logging tools are analyzed and/or interpreted by an electronic circuit in a well logging tool. The interpretation of these signals can be direct, differential, or summation measurements from the sensors. The signal interpretations can be qualitative or quantitative, depending on how the tool is set up or programmed of the electronic circuit. When gas/oil, gas/water, or oil/water contacts are made in the well bore, the circuit will send a signal to a set of electromagnets or a drag mechanism that will momentarily grab the walls of the pipe. This will create a line tension spike on the load cell/weight indicator on the surface, and a well log can be generated to show where these line tension spikes occur, thus indicating the depth of various fluids in the well bore.

Abstract: The present invention provides a method for forming wellbores. In one method, one or more wellbores are drilled along preplanned paths based in part upon seismic surveys performed from the surface. An acoustic transmitter conveyed in such wellbores transmits acoustic signals at a one or more frequencies within a range of frequencies at a plurality of spaced locations. A plurality of substantially serially spaced receivers in the wellbores and/or at surface receive signals reflected by the subsurface formations. The sensors may be permanently installed in the boreholes and could be fiber optic devices. The receiver signals are processed by conventional geophysical processing methods to obtain information about the subsurface formations. This information is utilized to update any prior seismographs to obtain higher resolution seismographs. The improved seismographs are then used to determine the profiles of the production wellbores to be drilled.

Abstract: A system for evaluating multiphase fluid flow in a wellbore. Two distinct AC signals are injected into a fluid. One AC signal originates from a transmitter electrode in ohmic contact with the fluid, and the other AC signal originates from a transmitter electrode capacitively coupled to the fluid. The geometric factors between the electrode pairs are selected to distinguish between different constituents within the wellbore fluids. The output electrical impedance of the ohmic transmitter is low so that the AC signal from the capacitive transmitter is shunted to signal ground in electrically conductive fluids. A single detector can measure the fraction of electrically conductive water covering the detector electrode as well as the dielectric constant of an oil and gas mixture. Arrays of such detector electrodes can measure the holdups and velocities of the constituent fluids in a flowing multiphase fluid.

Abstract: A system is provided for monitoring in the real time the wellbore pit volume to promptly determine the occurrence of a wellbore kick and take corrective action to minimize fluid influx volume and/or drilling fluid losses. A system includes one or more level sensors 22 which output signals to a pit volume totalizer 20 and then to a computer 26. Computer 26 may also receive signals from one or more fluid temperature sensors 40 and one or more fluid compressibility sensors 42. The output from the computer may be displayed in real time in various monitors 28, then also may be output to a permanent record 30. Computer 36 may also automatically activate the conventional alarm 32 to alert the drilling operator to the occurrence of a kick. Substantial savings in drilling time and cost may be realized according to the present invention, along with benefits of reduced environmental contamination and enhanced well safety.