In the hydrocarbon recovery art, boreholes often extend through long, hydrocarbon bearing formations that have varying production potential over that length. Moreover, it is common for hydrocarbon bearing formations to also contain gas and/or water that are not desirable to produce. Due to the noted variable production rates in different axial locations along the borehole, water and/or gas breakthrough can occur at different times. This is clearly undesirable since an early breakthrough will require either an expensive remedial action or might even result in a shutdown of the well altogether.
One means of combating such early breakthrough is the employment of inflow control devices, commercially available devices to tailor resistance to fluid inflow to the borehole from the formation. By selectively adding flow restriction, a fluid inflow rate profile along the axial length of the borehole can be controlled by slowing down inflow rate in sections of the formation where a rapid inflow would be expected to result in an early breakthrough of an undesirable fluid. Through such selective inflow rate restriction, the entirety of the borehole production can be improved, avoiding early breakthrough.
An inflow control device comprising a housing; a fluid inlet to the housing; a fluid resistance pathway defined within the housing; a fluid outlet from the resistance pathway leading to a fluid flow passage; and an exit sensor positioned to measure a fluid parameter in the fluid flow passage immediately downstream of the resistance pathway. A method for monitoring an effect of an inflow control device on a wellbore comprising: allowing fluid to flow through the inflow control device; and measuring a fluid parameter at an inside dimension of the inflow control device downstream of a fluid outlet from the inflow control device. A method for monitoring a phase profile in a wellbore comprising: allowing fluid to flow through a plurality of inflow control devices in a production string; measuring a fluid parameter at least a plurality of the plurality of inflow control devices; and creating a phase profile of a downhole environment immediately adjacent to the plurality of inflow control devices based upon the measured fluid parameter.
Referring now to the drawings wherein like elements are numbered alike in the several Figures:
As used herein, an inflow control device is defined as a device to be placed in a well to passively control the inflow from the hydrocarbon bearing formation to the base pipe of the well. The basis of the device is the fluid resistance pathway that provides a radial flow resistance from the formation to the basepipe. While inflow control devices (sometimes referred to as an “ICD”) are expected by the art to balance a flow profile in a borehole through selective resistance to fluid inflow from a formation, delivery on that expectation is based upon earlier measurements including logging measurements. Since there is no capability in the art, however, to monitor a fluid parameter at the inflow control device, changes in the flow profile over time that would foretell an early breakthrough will go unnoted and thus unaddressed by an operator. Such information, if known, could help an operator avert an early breakthrough. Heretofore, no method or apparatus has been available to provide such information.
Referring to
It has been determined by the present inventor that by placing a fluid parameter exit sensor 24 downstream of fluid outlet 18 and within reasonable proximity thereto, a flow rate profile can be mapped in an individual inflow control device. In one embodiment, and as illustrated in
While in the above-identified embodiment the single sensor 24 does indeed provide valuable information regarding flow profile at the inflow control device with which it is associated, it is noted that even greater reliability with perspective dating can be achieved at an inflow control device valve as a sensory component is located both inside the housing 12 and outside the housing 12 such that a differential in the measured parameter may be tracked. In such an embodiment, a housing sensor 26 is placed at the outside of housing 12 in addition to sensor 24 at the inside dimension of the housing 12. This housing sensor may be located anywhere about the inlet 14 providing it is reasonably close enough to accurately sense a parameter of the wellbore affecting inlet 14. In one embodiment, the sensor 26 would be placed within about one zonal isolation length of the inlet 14. If, for example, pressure is the parameter that is being monitored, the first pressure measurement is sensed at sensor 26 and a second pressure measurement is sensed at sensor 24. If there is a difference in the pressure between sensor 26 and sensor 24, the difference in that pressure is related to the flow profile. Over time, change in the flow profile can be correlated to the health of the wellbore itself in the immediate vicinity of the inflow control device 10. Such information is useful to the well operator in that it facilitates decisions that need to be made about closing off particular inflow control device before a breakthrough of an unwanted fluid occurs. Further, while this example indicates that a single parameter is used both on the inside and outside of the housing 12, it is also possible to use differing parameters and then mathematically resolve the information sought by the operator.
It is to be appreciated that sensors 24 and 26 are placed in
Although a single inflow control device is illustrated in
While pressure and temperature have been disclosed as potential parameters that may be monitored, it is to be understood that other parameters such as viscosity, etc. or multiple parameters might be used instead or in addition thereto. Because the resistance of the inflow control devices and their geometry, the various parameters can be plugged into appropriate equations to mathematically derive the information desired by the operator. In order to obtain such results, the following equation is of use:
where the friction factor, f, is a function of the Reynolds number, which is a function of the fluid density, fluid viscosity, fluid velocity, and the hydraulic diameter; L is the length of the fluid passage over which the change in pressure (delta P) is measured; D is the hydraulic diameter of the passage; K is the loss coefficient, which varies based upon the geometry of the passage and is equal to the sum of the inlet and outlet acceleration losses; rho is the fluid density; V is the velocity of the fluid; and g is gravity.
In another embodiment, referring to
In yet another embodiment is sensor configurations taught herein i.e. an exit sensor alone or an exit sensor and an inlet sensor (akin to the housing sensor disclosed above) can be utilized in conjunction with a commercially available inflow control device known by the tradename equiflow from Halliburton, Houston, Tex. The same benefits are achieved with the configuration, the only distinction being the form of the fluid resistance pathway.
While preferred embodiments have been shown and described, modifications and substitutions may be made thereto without departing from the spirit and scope of the invention. Accordingly, it is to be understood that the present invention has been described by way of illustrations and not limitation.