Near well simulation of oil production from heavy oil reservoirs

Abstract

During the last some years, there has been a lot of discussion about the challenges in the field of heavy oil production in horizontal wells. The Autonomous Inflow control Valve (AICV), which has been developed by InflowControl AS, is self-regulated and does not require external force to control the flow. AICV is a very new technology which has the capacity to increase the recovery of heavy oil from horizontal wells. In this report, a computational study of a thin horizontal reservoir section with AICVs is presented, discussed and compared with the conventional ICDs. The near well reservoir section is modeled by using reservoir simulation software Rocx in combination with OLGA. Two different cases were simulated for a well section of 992m. One case is with conventional ICD and another case is with AICV. Both cases were simulated with a differential pressure of 10bar. The reservoir section considered in both cases is homogeneous with permeability 5Da. The initial total oil production rate for both cases was 2500 m3/day. First, water breakthrough occurs in the heel side of the well due to heel-toe effect. When water break through occurs, the first AICV in the heel chokes the water production locally while the other AICVs are producing oil. In the similar manner, the other AICVs close locally after water breakthrough. Thus the water-cut is controlled and remains low. This gives a good representation of the AICV action and the recovery is increased. AICV can works reversibly also. The meaning is that the closed AICV starts to produce oil if it encounters higher concentration of oil. This reverse AICV action was observed in simulation after 10 days of production. The simulation shows that the recovery of heavy oil production with AICVs is increased by approximately 21% compared to conventional ICDs.