PROCEDURE FOR DEVELOPMENT OF HIGH VISCOUS OIL DEPOSITS Russian patent published in 2009 - IPC E21B43/24 E21B7/04 E21B43/10 

FIELD: oil and gas industry.

SUBSTANCE: invention refers to procedure of development of high viscous oil deposits. The procedure consists of drilling a main borehole of the well, wherefrom a side horizontal borehole is drilled; in lowering a perforated column into it; in lowering a flow string into the main borehole of the well; in installing a packer below the interval of kickoff of the side horizontal borehole, notably, the said packer seals space between the flow string and the main borehole; in pumping heat carrier through one borehole and in withdrawing high viscous oil or bitumen from another borehole of the well. Before installation of the packer a deflector is lowered on the flow string into a low uncased part of the main borehole of the well; the deflector with its outlet opening is directed to the side horizontal borehole and below it within the boundaries of the same producing reservoir. Located under the side horizontal borehole section is formed by means of a flexible pipe with a jet-head. The flexible pipe and the flow string with the deflector are pulled out from the well. After installation of the packer, but before lowering the flow string the latter is fitted out with a pipe filter and with a nipple mounted above; the nipple is equipped with the deflector furnished with an opening made in the wall of the flow string above the nipple; also the flow string is provided with a bypass. The inlet of the bypass is communicated with above wedge space of the flow string, while its output is connected to under the nipple space of the flow string. The flow string is lowered into the main borehole of the well till nipple pressure tight interacts with the packer; notably, the pipe filter will be arranged opposite to the interval of kickoff of the side horizontal borehole of the packer. Further, the perforated column on the process column with an additional packer is lowered via the flow string, the deflector and the opening into the side horizontal borehole till the perforated column is placed in its horizontal section. An additional packer is installed between the flow string and the process column above the opening, but below the inlet of the bypass. Heat carrier is pumped into the main borehole of the well via annular space of the flow string and process column, the bypass, under the nipple space of the flow string and the filter, while withdrawing of product is performed from the side horizontal borehole through the perforated column along the process column.

EFFECT: increased efficiency of heating high viscous oil deposit with heat carrier, when density of heated oil is below density of heat carrier; also reduced heat losses of heat carrier in well and efficiency of direct effect onto well walls during process of deposit development.

1 dwg