METHOD FOR ISOTHERMAL DIFFERENTIAL FORCED STEAM CYCLIC PRE-HEATING FOR TWIN HORIZONTAL WELLS OF MID-DEPTH LAYER OF OIL RESERVOIR

摘要

Disclosed is a method for isothermal differential forced steam cyclic pre-heating for twin horizontal wells of a mid-depth layer of an oil reservoir. The method for isothermal differential forced steam cyclic pre-heating for twin horizontal wells of a mid-depth layer of an oil reservoir comprises: step A: selecting a qualifying oil reservoir; step B: arranging twin horizontal wells in the middle of the qualifying oil reservoir; step C: simultaneously conducting steam huff and puff development on the upper horizontal well and the lower horizontal well, making the pressure of the qualifying oil reservoir be reduced to 3.5 MPa or less; step D: lowering an upper horizontal well steam-injection tubular column and an upper horizontal well mechanical hoist tubular column into the upper horizontal well of the twin horizontal wells, and lowering a lower horizontal well steam-injection tubular column and a lower horizontal well mechanical hoist tubular column into the lower horizontal well of the twin horizontal wells; and step E: cyclic pre-heating, the upper horizontal well and the lower horizontal well performing continuous injection and collection simultaneously, steam being simultaneously injected into the upper horizontal well and the lower horizontal well, while using the mechanical hoists to recover condensed liquid, condensed liquid in the upper horizontal well being collected from the upper horizontal well and condensed liquid in the lower horizontal well being collected from the lower horizontal well.