Many operators are considering installation of flow-control devices (FCDs) in horizontal wells to improve steam-oil ratios (SOR) in steam-assisted gravity drainage (SAGD) recovery processes in heavy oil/bitumen reservoirs. The flow-control devices are used to help balance both the steam injection and fluid production in order to increase the oil recovery efficiency and use the full length of the horizontal wells. SAGD injector and producer horizontal wells are typically 3 to 6 meters apart, vertically. Because of this proximity, steam breakthrough to the producer well is possible. In order to reduce the steam loss following a steam breakthrough, operators typically try to slow the total rate of production.
This paper will discuss the testing of passive inflow control devices (ICDs) and an autonomous inflow control device (AICD) in a steam-flow test loop along with testing results to help control the breakthrough of steam. Heated water flow through the ICDs and AICDs was used as the baseline case. Saturated steam simulating steam flow conditions (pressure and temperature) in a SAGD environment was flowed through the devices at two different temperatures, and the resulting flow rates were recorded at several pressure differentials.
The laboratory flow testing has helped demonstrate how the ICDs and AICDs can either help prevent steam breakthrough from occurring or limit the rate of steam breakthrough in the zones of concern. By limiting the flow rate of steam breakthrough, the flow control devices will also help to protect the sand screen from erosion caused by high velocity flow.