METHOD FOR FRACTURED HIGHLY-VISCOUS OIL RESERVOIR DEVELOPMENT Russian patent published in 2008 - IPC E21B43/24 

FIELD: oil field development, particularly methods for thermal reservoir treatment for highly-viscous oil production.

SUBSTANCE: method involves excavating mine in lower part of oil reservoir or under the reservoir; drilling gently ascending injection and producing wells from mine; providing the injection wells with flow strings; injecting steam in injection wells; producing oil from producing ones. Before steam injection in reservoir highly-viscous non-hardened solution is injected in hole annuities of injection wells. The highly-viscous non-hardened solution includes clay solution mixed with asbestos or basalt powder. Steam is periodically injected via injection wells. After steam breakthrough in some producing wells steam injection into injection wells, which are sources of steam breakthrough, is stopped. After temperature reduction up to 50-70°C steam injection is resumed. Injection wells non-sensitive or nearly non-sensitive to stream injection are converted into ones used for simultaneous steam injection and oil production. After steam breakthrough into hole annuities of said wells oil production therefrom is stopped. Before steam injection in hole annuity resumption highly-viscous non-hardened solution is additionally supplied as highly-viscous non-hardened solution level reduces to level lower than initial one.

EFFECT: increased reservoir recovery due to prevention of steam breakthrough in producing wells and mines by fracture filling with highly-viscous non-hardened compositions and due to extended coverage of non-heated reservoir zones with heating.

7 cl, 1 ex, 4 dwg