The paper discusses basic methods of behind-the-casing flow detection including temperature logging, spectral noise logging, injection of tracer-containing fluid, and application of a thermohydrodynamic simulator to quantify behind-the-casing flows. Each of these methods has its benefits, range of application, and limitations. Relevance of this paper is that it discusses a method of detecting behind-the-casing flow using a thermohydrodynamic simulator that enables estimation of wellbore temperature distribution based on the preset parameters of a numerically simulated model. It also determines the amount of behind-the-casing flow which is of primary importance for planning further well surveying. Thermal simulation results in obtaining behind-the-casing flow value, inflow/injectivity profile, flow rate of each separate reservoir. Implementation and application of this method results in reduced squeeze cementing costs for the wells where behind-the-casing flow is insignificant. When selecting an optimum well log survey technique, a variety of factors and downhole conditions shall be considered including well injectivity, well drive, reservoir pressure, gamma background, well design (whether perforations are open or closed off by completion assembly), sump size (small or absent), watercut, etc. ll wells have their own specific aspects which should be considered during survey technique selection. It is not unlikely that selection of the best technique will require individual approach to each well. For example, injection of fluid containing radioactive tracer will be inefficient in wells with low injectivity. In this case, it is recommended to use a suite of methods including temperature logging, inflow detectors, thermohydrodynamic simulation to determine the amount of behind-the-casing flow. Application of advanced well survey tools including casing integrity survey, detection of producing zones and behind-the-casing flows (temperature logging, inflow detectors, thermohydrodynamic simulation, spectral noise logging) results in better quality and reliability of the conclusion report, since the conclusions drawn are supported by several methods.
References
1. D’yakonov D.I., Leont’ev E.I., Kuznetsov G.S., Obshchiy kurs geofizicheskikh issledovaniy skvazhin (General course of geophysical surveys of wells), Moscow: Nedra Publ., 1984, 432 p.
2. Valiullin R.A. Vakhitova G.R., Kompleksnaya interpretatsiya geofizicheskikh dannykh na osnove tipovykh diagramm (Comprehensive interpretation of geophysical data based on standard diagrams), Ufa: Publ. of BGU, 2004, 94 p.
3. Marfin E.A., Skvazhinnaya shumometriya i vibroakusticheskoe vozdeystvie na flyuidonasyshchennye plasty (Downhole noise logging and vibroacoustic impact on fluid-saturated formations): Kazan: Publ. of Kazan University, 2012, 44 p.
4. Koskov V.N., Geofizicheskie issledovaniya skvazhin (Well geophysical surveys), Perm: Publ. of PSTU, 2005, 122 p.
5. Ramazanov A.Sh. et al., Thermal modeling for characterization of near wellbore zone and zonal allocation (In Russ.), SPE-136256-MS, 2010, https://doi.org/10.2118/136256-MS
