DOWNHOLE SEPARATION DEVICE

摘要

A device for separation of well streams and injection of separated water into the wellbore has been described, which device is arranged in a wellbore, and which device comprises at least three stages of separation, each stage of separation comprising a hydrocyclone group (2, 5, 8), where each hydrocyclone group comprises one or more hydrocyclones connected in parallel, and where a well stream (10) comprising an oil fraction, a water fraction, a sand fraction and possibly a gas fraction is led to a first hydrocyclone group (2) for separation into an oily stream (3) and a stream (4) containing oil residue, sand and water, which stream (4) is led to a second hydrocyclone group (5) for separation into an oil and water-containing stream (6) and a sand-containing stream (7), which stream (6) is led to a third hydrocyclone group (8) for separation into an oily stream (9) and a water-containing stream (10), which water-containing stream (10) is injected into a suitable area of the reservoir through the wellbore. The separation device may be combined with various other separators and process equipment.