Application of multilateral wells with limited sand production to heavy oil reservoirs

Multilateral wells with limited sand production are proposed to produce offshore heavy oil reservoirs. This technique was studied through lab experiments and numerical simulation. Permeability increases with sand production and formation fines of less than 39 μm diameters are the main fines that jam pore throats and influence permeability the most. For a given total length of branches, productivity slightly decreased with increasing branches, suggesting that the number of branches should not be very higher, two or three are better; and productivity increased with the increase of branch angles, but the increase of productivity decreases. Field test was carried out in NB35-2 oil field and the individual layer deliverability of a multilateral well with limited sand production is three times the multilayer production of the common deviated well.