Once the steam-assisted gravity drainage (SAGD) method has begun to be used on a wide scale to produce heavy oil/bitumen reserves it has become possible to develop reservoirs with immobile hydrocarbons. The economics of the SAGD process strongly depends on the steam generation efficiency, steam delivery, and steam usage efficiency in successful and unsuccessful SAGD well pairs. The success of a SAGD well pair is often dictated by how efficiently steam is used in the inflow/injection profile of a SAGD well pair. Completions involving inflow control devices (ICDs) promise to improve the economics of the process by improving the inflow profile and mitigating the irregularities in steam injection and fluid production along the horizontal wellbore. Traditionally, ICDs have been used in lengthy wellbores characterized by pressure drops along the entire length to control and equalize the inflow profile and to delay water breakthrough. In SAGD wells, ICDs have found new application providing for a uniform steam distribution in the injection well and an evenly distributed fluid flow profile in the producing well, maximizing, thus, the heavy oil recovery. The operation of autonomous inflow control devices is based on increase of resistance to flow in response to increase of fluid rate through a section in heavy oil completions. The paper presents the results of research into the effectiveness of ICDs, principle of their operation, and applicability in Tatarstan heavy oil fields. Algorithm of ICD losses calculation was determined, and ICD losses for wells producing heavy oil were calculated. Typical cases were considered, variations in productivity of horizontal wellbore sections with ICDs were determined by calculation. The results of the research show that ICD can partially choke the problem intervals (by 10 % zones with water coning and by 2 % zones with steam breakthrough), and help to achieve an evenly distributed flow profile along a horizontal well. Thermodynamic analysis of two types of inflow control devices was performed, ICD losses calculating formulae were adapted to be used in reservoir flow models, and ICD long-term effect considering changes in reservoir conditions was assessed.
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