METHOD OF OIL FIELD DEVELOPMENT WITH HORIZONTAL WELLS Russian patent published in 2015 - IPC E21B43/20 

FIELD: oil and gas industry.

SUBSTANCE: method involves construction of horizontal producers covering the field, and horizontal injectors. Displacement agent is injected through injectors, and products are swept by producers. Horizontal production wells are arranged parallel to each other. Horizontal injector is positioned between horizontal sections parallel to them. Injection starts from bottomhole. When intake capacity of reservoirs is decreased at the bottomhole of horizontal injector to minimum profitable level, non-operating section of horizontal shaft is isolated in series in direction from the bottomhole to the beginning of horizontal injector wellbore. Horizontal producers are drilled in permeable interlayer at 3-6 m distance below the reservoir bottom and at least at 10 m distance above oil-water interface. Horizontal injector is equally spaced from horizontal sections of producers by a design pattern distance. Displacement agent is injected with reservoir pressure rise by 10-20% compared to recovery zone. After time period sufficient to recover and stabilise frontal zone of liquid injected to the reservoir, operation may return to previous intervals. Horizontal sections of producers are broached in two intervals at a distance preventing hydrodynamic connection of the wells. Products are recovered in turns. Production intervals are switched when products reach minimum profitable water cut level.

EFFECT: increased oil recovery due to stabilisation of frontal zone of liquid injected to reservoir, extended application scope of horizontal wells in various field development conditions.

6 dwg, 1 ex