Steam injection

In the name of God

Steam Injection Enhanced Oil Recovery

Course Instructor :

Dr. Behnam Sedaei

Introduced by:Yusef Haghshenas

Hamed Mousanejad Kermani

Mohammad Javad Derakhshan

Date: 15th December 2016

Introduction

Steam injection technology, introduced in the 1970.

It is the type of thermal EOR method are generally applicable to heavy , viscous crudes, and involve the introduction of thermal energy or steam into the reservoir to raise the temperature of the oil and reduce its viscosity, increase in permeability.

Steam flooding

Injected into a number of injection wells continuously.Heavy Oil produced by stimulation before flooding is started-flow communication.steam drives the mobilized oil toward the producers.

Zones:1.Condensing Zone2.Saturated-Steam Zone3.Transition Zone4.Displacement Zone

Mechanism Viscosity change Relative permeability change Thermal expansion Vaporization / condensation Steam distillation Catalytic and thermal cracking Light hydrocarbon and / or CO2 dissolution Swelling because of Light hydrocarbon and / or CO2 dissolution

Advantages

Cost of operation

Simple process

High recovery factor compare to water flooding

Disadvantages Oil saturations must be quite high and the pay zone should be more

than 20 ft thick to minimize heat losses to adjacent formations. Lighter, less viscous crude oils can be steam flooded but normally

will not be if the reservoir will respond to an ordinary water flood. Steam flooding is primarily applicable to viscous oils in massive,

high permeability sandstones or unconsolidated sands. Steam flooding is not normally used in carbonate reservoirs. Heat loss of the steam. The distance of the Injection and production well should be enough

for heat to spread in the reservoir. Carbon dioxide emission. Energy source for steam generation. Steam override and premature breakthrough.

Goals of researches

Increasing recovery factor Decreasing steam oil ratio Decreasing heat loss Decreasing water cuts Decreasing the requirement for energy Decreasing the cost of operation (cost of steam generation)

Cyclic steam stimulation

essentially a single well operation, with the same well used for injection and production.

oil production rate and the total oil production in the second cycle is less than that in the first, and declines in subsequent cycles.

effective over a short radial distance from the well. Recovery factor about 20-25 % of the Original Oil in Place (OOIP). Disadvantage that the cost to inject steam is high.

Cyclic steam stimulation

Steam assisted gravity drainage ( SAGD )

Steam Assisted Gravity Drainage is an enhanced oil recovery technology for producing heavy crude oil and bitumen. It is an advanced form of steam stimulation in which a pair of horizontal wells is drilled into the oil reservoir, one a few meters above the other. High pressure steam is continuously injected into the upper wellbore to heat the oil and reduce its viscosity, causing the heated oil to drain into the lower wellbore, where it is pumped out

Steam assisted gravity drainage ( SAGD )

Steam injection

Heat generated at the surface:

Steam Drive (Steam flooding) Steam Cyclic Steam Stimulation ( huff-and-puff ) Steam assisted gravity drainage ( SAGD )

Water injection after steam flooding

Economic production of oil.

Reducing the consumption of the fuel.

Prevent the oil from coming back to swept areas.

Spread the heat in reservoir and sweep the areas that steam round them.

Water alternating steam process (WASP)Water alternating steam process, WASP, is a technique designed to overcome the problems associated with steam injection. It involves injection of alternating steam and water slugs for more than one cycle, in order to improve the injection front because, due to their nature, injected fluids run through different areas of the field that have not been contacted and that have considerable amounts of hydrocarbons. The technique was evaluated by numerical simulation on a heavy oil reservoir located in the MiddleThe technique was evaluated by numerical simulation on a heavy oil reservoir located in the Middle Magdalena Valley basin.

Water alternating steam process (WASP)

Enhancing heavy oil recovery by steam-air combination floodingAir is the most common gas and furthermore, the low cost of the collection of air makes air an available addictive gas.Mechanism of steam-air combination flooding: Air can enhance the drainage energy of oilCompared with other gas such as CO2 , natural gas, fuel gas and so on, air has a much greater compressibility coefficient. Even in a higher temperature, the compressibility coefficient of air is still high. So air contains more energy and if reservoir pressure drops, more oil will be extracted. Air can enhance the heat utilization factor of steam flooding Air has a low coefficient of heat conductivity, which is only 0.0288W/m. K. When air is co-injected with steam, air will occupy the upper location of the reservoir and thus prevent heat from conducting to the cap rock. Therefore, the bottom of the reservoir can better heated by injected steam and more oil will be produced and heat utilization efficiency will be increased.

Enhancing heavy oil recovery by steam-air combination flooding

Enhancing heavy oil recovery by steam-air combination flooding

Solvent-aided steam flooding

The formation of the solvent channel led to oil-solvent mixing at the periphery of the channel as well as heat transfer to oil beyond the channel, which leads to better recovery performance. In the the presence of a bottom water zone, the optimized steam injection pressure optimization strategy was found to perform poorly. However, the optimized solvent-aided strategy achieved superior economics. With solvent injection, the presence of the bottom ater zone enhanced mixing of solvent and oil yielding better oil recovery performance.


With out bottom water



With bottom water


Improving SAGD performance combining with css

The SAGD and CSS process were combined together to benefit advantages of both methods. When the wells are shut-in to soak, infectivity of steam during SAGD process will increase .So the chamber can extend more easily to drain the oil toward production wells. The production performance of this method is compared to conventional SAGD and CSS process. Simulation results show that with the same steam injection rate, this new method has more oil recovery than conventional SAGD, due to better development of steam chamber into reservoir. Also as a result of lower steam-oil-ratio the production cost is reduced.



Expanding solvent Steam assisted gravity drainage (ES-SAGD)

The Expanding Solvent-SAGD (ES-SAGD), is aimed at improving and extending SAGD performance by solvent addition to steam. The improvements include higher and faster drainage rates, lower energy and water requirements and reduced green house gas (GHG) emissions.

In the ES-SAGD process, the solvent or solvent mixture additive, whose vaporization thermodynamic behavior is similar, or close, to that of water thermodynamic behavior for a given reservoir condition is considered the most appropriate.



SAGD

Case 2

Case 3



Convective SAGD process

In steam assisted gravity drainage (SAGD) process, accumulation of non-condensable gases at the edges of the steam chamber creates a resistance to heat transfer between hot steam and cold bitumen, thus slowing down growth of the steam chamber. Efficient removal of these gases from the steam chamber can substantially accelerate the recovery process.

Typical practice in SAGD is to use steam splitters and strive for a relatively uniform pressure in the horizontal part of the well, which allows for even distribution of injected steam into the reservoir. In convective SAGD process, a significant pressure gradient is deliberately created along the horizontal length of the injector well by tailoring the well completion design.

Currently, a field pilot is being pursued at Foster Creek to test the validity of convective SAGD process.




Vertical single well SAGD producers (SW-SAGD)Shallow-field experiments demonstrated thatvertical planes could be injected on azimuth in weakly cemented formations (Hocking 1996). Continuous permeable planes filled with an iron proppant—in some cases, kilometers in length—have been constructed using this technology for groundwater remediation at numerous sites (Hocking and Wells 2002). More recently, shallow-field experiments have demonstrated that multi-azimuthpermeable planes can be installed from a single well in weakly cemented formations (Hocking et al. 2008). The technology is not limited by depth, but is limited to formation strength, being that it is applicable only in weakly cemented formations. This process has now been extended to depths greater than 500 m (Hocking et al. 2011a & 2013) and is proposed as a new thermally enhanced well-completion system for heavy-oil and bitumen recovery in unconsolidated sands where conventional thermal recovery methods, such as SAGD and cyclic steam stimulation (CSS) have limitations because of geological issues.

Vertical single well SAGD (SW-SAGD)

Vertical single well SAGD (SW-SAGD)

The end

Refrences Jian Yang, Xiangfang Li, Darong Xu, Yiqun Yan, Jing Li, and Sidong Fang, China

University of Petroleum; Baorui Zhang, Promotion Association for Special Equipment Safety and Energy Saving, Research of Enhancing Heavy Oil Recovery By Steam-Air Combination Flooding, 20 –22 October 2015

David W. Zhao, Jacky Wang, and Ian D. Gates, Department of Chemical and Petroleum Engineering, Schulich School of Engineering, University of Calgary, Solvent-Aided Steam-Flooding StrategyOptimization in Thin Heavy Oil Reservoirs, 26–28 March 2013.

G. Hocking, SPE, GeoSierra LLC; D. A. Walters, SPE, Taurus Reservoir Solutions Ltd, Vertical Single-Well SAGD with Multiple Producers, 11–13 June 2013.

M. C. Ariza, A. Perez, A. X. Rodriguez Castelblanco, and S. F. Munoz Navarro, Universidad Industrial de Santander, Water Alternating Steam Process WASP Simulation Study in a Colombian Heavy Oil, 13–15 June 2016.

Arun Sood, Cenovus Energy, Convective SAGD Process, 7–9 June 2016. E. Ghanbari, S. Mighani, E. Shaabani and R. Alipour Yeganeh Marand, Amirkabir

University of Technology, Improving SAGD Performance Combining with CSS, 7–9 February 2012.

T.N. Nasr and O.R. Ayodele, Alberta Research Council, New Hybrid Steam-Solvent Processes for the Recovery of Heavy Oil and Bitumen, 5–8 November 2006.

B.W. Orr, SPE, Nexen; P. Srivastava, SPE, V. Sadetsky, SPE, B.J. Stefan,SPE, Baker Hughes, Reducing Steam Oil Ratio in Steam-Assisted Gravity Drainage, 19–21 October 2010.

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Steam injection