Steam injection (oil industry)

Steam injection is widely used in the San Joaquin Valley of California (US), the Lake Maracaibo area of Venezuela, and the oil sands of northern Alberta, Canada.

[1] Another contributing factor that enhances oil production during steam injection is related to near-wellbore cleanup.

Steam is first injected into a well for a certain amount of time to heat the oil in the surrounding reservoir to a recover approximately 20% of the original oil in place (OOIP), compared to steam assisted gravity drainage, which has been reported to recover over 50% of OOIP.

This process is repeated until the cost of injecting steam becomes higher than the money made from producing oil.

[3] The CSS method has the advantage that recovery factors are around 20 to 25% and the disadvantage that the cost to inject steam is high.

"Steam is re-injected to begin a new cycle when oil production rates fall below a critical threshold due to the cooling of the reservoir.

The first is to heat the oil to higher temperatures and to thereby decrease its viscosity so that it more easily flows through the formation toward the producing wells.

A second mechanism is the physical displacement employing in a manner similar to water flooding, in which oil is meant to be pushed to the production wells.