Production and injection profiles are very important information required for good reservoir management. Typically, the production and injection profiles are obtained via running a production logging (PLT survey. Unfortunately, conventional PLT surveys may not work for a number of well scenarios, such as pumping wells, HP/HT wells, low rate wells, or be expensive, especially for subsea well completions.
In the present paper, the major challenges facing the conventional production logging surveys will be discussed. Possible efforts to overcome the challenges will be illustrated.
Experience indicates that under certain circumstances, unconventional approaches may be applied to profile production and injection. This paper will introduce two unconventional flow profiling approaches that have recently been developed. Both approaches are built upon real-time permanent downhole measurement data and thus may make real-time flow profiling a reality.
The first approach uses fiber-optic distributed temperature sensor (DTS measurement to profile the production or injection along a well. DTS, one of the modern permanent monitoring technologies, can record the wellbore temperature profile in real time with decent accuracy and resolution. A thermal model recently developed for single phase and multiphase fluid flow along a vertical, deviated or horizontal well will first been briefly described. The model has been successfully adapted for directly predicting production and injection profiles based on given wellbore temperature profile data like those from DTS.
The second approach is related to production and injection profiling through permanent downhole pressure gauge (PDG data recorded during any coiled-tubing deployed workover operation, a novel and unique application. Theoretical development of the new technology will first be addressed. Examples will then be provided to illustrate the application of the technology. Application scenarios, practical issues as well as key impacting parameters will be discussed. Finally, a field case study implementing the new technology for a long horizontal well will be performed to demonstrate how the production profiles from PDG data compare to the results from a recent PLT survey that turns out to be quite expensive yet unsatisfactory. The technology could be applied to real-time production and injection profiling for different well configurations (vertical, horizontal, deviated and multilateral and bring tremendous financial benefits through replacing conventional production logging surveys that could be cost-extensive for horizontal or multilateral wells offshore.