Steam-Foam Technology as an Option to Improve Steam Drive Efficiency

Abstract

The steam-foam process is an Enhanced Oil Recovery (EOR) method which aims to improve the performance of a traditional steam drive by using a foaming surfactant. A Canadian thermal project under development in NW Alberta, which will use steam drive to recover extra heavy oil from the Bluesky Reservoir, is a good candidate for the application of steam-foam. A pilot test is planned to evaluate the benefits of the steam-foam process in this reservoir.The steam-foam process is based on the use of a surfactant which, when co-injected with steam into the formation, generates foam. A candidate surfactant for steam-foam should be able to generate stable foam at high temperature, have a good thermal stability, a low rate of adsorption on the rock, and good solubility in brine. An experimental plan was designed to screen for appropriate surfactants to use in the field. Bulk foam height tests at high temperature, thermal degradation tests and static adsorption tests with disaggregated rock were carried out to screen the best surfactant. Two candidate surfactants were chosen based on the results. A pilot test plan was also developed for a proof-of-concept test of the candidate surfactant in the field. The primary success criterion for the test is an increase in the Bottom Hole Pressure (BHP) of the injector well after the start of surfactant injection.Core-flooding tests are currently underway to confirm the performance of the candidate surfactant in the porous medium and determine the value of parameters required for the pilot design. The generation of strong foam in the formation should result in not only a BHP increase in the injector, but also improvement of the Steam to Oil Ratio (SOR) and ultimate recovery. The oil uplift response is dependent on the pattern geometry and geology of the reservoir and may not be observed immediately. However, the BHP increase will be immediately observed provided that strong foam has been generated near the wellbore, and this is the focus of the proof-of-concept test. A more extensive field test is planned for a later date to evaluate SOR improvement and recovery uplift.

Investigation of Nanoclay-Surfactant-Stabilized Foam for Improving Oil Recovery of Steam Flooding in Offshore Heavy Oil Reservoirs

“…Foam-assisted steam flooding is an effective technology to improve the sweep efficiency of steam flooding by inhibiting the steam channeling and gravity override, thus increasing the oil recovery of steam flooding. − The high-temperature foam agent can not only inhibit the steam overriding but also reduce the steam mobility. Besides, the foam also has the selective blocking characteristics, which can block the big pores rather than the small pores and block the water layers rather than the oil layers. , It is indicated that the foam is an ideal high-temperature profile control and flooding agent, and thus, foam is widely used in steam flooding for improving heavy oil recovery. , The experimental results by Bagheri and Clark showed that foam-assisted steam flooding could achieve good results, which verified the application prospect of foam-assisted steam flooding in the Canadian thermal recovery project being developed in northwest Alberta . Wang et al carried out physical simulation experiments to prove that the flue gas foam-assisted steam flooding technology had a good ability to improve the recovery of steam flooding. , …”

“…6,7 The experimental results by Bagheri and Clark showed that foam-assisted steam flooding could achieve good results, which verified the application prospect of foam-assisted steam flooding in the Canadian thermal recovery project being developed in northwest Alberta. 8 Wang et al carried out physical simulation experiments to prove that the flue gas foam-assisted steam flooding technology had a good ability to improve the recovery of steam flooding. 9,10 It is well-known that the foam thermal stability is the key problem in steam flooding to improve the sweep efficiency.…”

Evaluation of Steam-Foam Flooding in Multi-Layered Heterogeneous Reservoir

“…communication and/or channeling in a layered formation with poor vertical communication between sand members. In order to minimize drawbacks of steamflooding, steam-foam flooding, the combination between surfactant and steamflooding, was developed [12]. Surfactant can reduce surface tension of liquid and then reduces the work needed to create foam.…”