US20130284435A1

US20130284435A1 - Satellite steam-assisted gravity drainage with oxygen (sagdox) system for remote recovery of hydrocarbons

Info

Publication number: US20130284435A1
Application number: US13/888,874
Authority: US
Inventors: Richard Kelso Kerr
Original assignee: Nexen Inc
Current assignee: CNOOC Petroleum North America ULC
Priority date: 2011-07-13
Filing date: 2013-05-07
Publication date: 2013-10-31

Abstract

A SAGDOX satellite system for recovering hydrocarbons includes a central SAGDOX site, at least one SAGDOX satellite site, and a pipeline corridor for communication between the central SAGDOX site and the SAGDOX satellite site. The satellite system is designed to recover hydrocarbons using a SAGDOX process at the satellite site and transfer recovered hydrocarbons to the central site.

Description

BACKGROUND OF THE INVENTION

The Athabasca Oil Sands is one of the largest oil deposits in the world. It contains 2.75 trillion barrels of bitumen resources, including carbonate deposits (Butler, R. Thermal Recovery of Oil and Bitumen, Prentice-Hall, 1991). The recoverable resource (excluding carbonate deposits) is currently estimated at about 170 billion barrels. (CAPP, The Facts on Oil Sands, November 2010). 20% of these resources is recoverable by mining and the other 80% is recoverable by in-situ Enhanced Oil Recovery (EOR) (CAPP, 2010).
The leading in-situ EOR process to recover bitumen is steam-assisted gravity drainage (SAGD), a steam-only process. Table 1 provides typical production of leading producers in the industry based on SAGD. However, SAGD does have some limitations. Studies indicate that the economical limit for steam transportation, using an insulated pipeline, is about 10 to 15 km (Finn, A., Integration of Nuclear Power with Oil Sands Extraction Projects in Canada, MIT Thesis, June 2007), (Energy Alberta Corporation, Nuclear Energy: Hedging Option for the Oil Sands, CHUA, presentation Nov. 2, 2006), (PAC, Clean Bitumen Technology Action Plan, April 2011).
More specifically, bitumen production is limited because of the following SAGD central plant characteristics: 1) plant life is limited to 40 years at 90% average availability; 2) the available land for SAGD is 30% of the total (either due to reservoir quality, surface access or lease ownership issues); and 3) the average SAGD pattern size is 1000 m×100mth with an average pattern bitumen recovery of 1.5 million barrels (bbls) (411 bbls/day for 10 years). This means that the maximum size for a self-contained bitumen supply, without any satellite plants, based on the above assumptions, is 108,000 bbls/day. Over the assumed 40 year life of a SAGD central plant, the maximum-sized SAGD central plant will recover 1.4 billion barrels of bitumen. In order to fully recover the recoverable resources, there would be a need for about 100 central SAGD maximum sized plants and about 100,000 average SAGD patterns.
One option available to increase bitumen production would be for a large central bitumen producer using SAGD to construct a remote, smaller plant. The SAGD central plant supplies services and some feeds to the remote, preferably smaller SAGD plant as opposed to constructing a new stand-alone (greenfield) SAGD central production plant. This SAGD smaller, remote plant is referred to as a bitumen satellite plant. A bitumen satellite plant is defined as a satellite plant for bitumen production that is “tied” to a central plant by a pipeline corridor. The pipeline corridor supplies a significant amount of input feeds from a central SAGD plant to the satellite SAGD plant, and it returns bitumen (or bitumen and diluent, or bitumen and water) to the central plant.
There are several choices for conveying bitumen and water (produced fluid mix) from a satellite plant to a central plant. The following are examples:

- 1. Push Water Systems—bitumen and water may be conveyed together without chemical additions in a gathering line system (Integra Engineering, Pushwater Systems Extend Heavy Oil Collection, 2011). The mixture may be thought of as a bulk oil/water (O/W) emulsion or blob flow. Commercial systems operate at distances up to 12 km (Integra (2011)).
- 2. Oil-in-Water Emulsions (O/W)—these emulsions may be created and stabilized by adding shear and chemicals to produced fluids. O/W emulsions may be stable and pumped with as low as 30% (v/v) continuous-phase water (Wikipedia, Orimulsion, 2011), (Xinhua Economic News, China's First Orimulsion Pipeline Comes on Steam, Nov. 7, 2006), (Brennan, J. R, Screw Pumps Provide High Efficiency in Transport of Orinocco Bitumen, P and G Journal, March 1995), (Stockwell, A., et al., Transoil Technology for Heavy Oil Transportation: Results of Field Trials at Wolf Lake, SPE 18362-MS, October 1988).
- 3. Diluent and Bitumen mixture “Dil.bit”—Today, dil.bit is the commercial choice for long distance pipelining of bitumen. But, for a satellite plant this would require oil-water separation (oil treating plant) and produced water reuse or disposal. For a satellite plant with a strategy to minimize capital and operating costs, this is an option but not preferred.
- 4. Diluent and Bitumen and Water mixture—diluent may be added to the produced fluid mix. One advantage of this is that the oil phase has reduced viscosity, so that if the conveyance pipeline is shut down in cold weather, the oil phase will not block a restart. The disadvantage is that the water concentration is reduced in the mix, so that push water flow and emulsion flow may be more difficult.

The SAGD satellite plant described above is desirable for the following reasons:

- 1. Steam cannot economically be supplied to fully integrate the SAGD satellite plant with the SAGD central plant.
- 2. Lands around the central SAGD plant have already been exploited.
- 3. The SAGD remote, satellite plant has more productive reservoirs.
- 4. The operator owns the land rights at the SAGD satellite plant.
- 5. The operator wishes to start another SAGD satellite plant that may eventually turn into a SAGD central self-sufficient plant.
- 6. Expansion of the SAGD central plant (brownfield expansion) and delivery of products (and acceptance of bitumen) is more cost effective than construction of a new (greenfield) project at the SAGD satellite plant.
- 7. Stand-alone SAGD satellite plant can be operated using some (most) of the SAGD central plant staff, thus saving operating expenses.
- 8. Construction of new SAGD central plants needed (e.g. Oil/Water separation) can better take advantage of economies of scale for engineering, design, construction, and operation.
- 9. Process reliability may be improved.
- 10. It is harder to control construction costs at a new greenfield plant compared to an existing brownfield plant site. Therefore, in a satellite plant, there is motivation to maximize the proportion of capital expenditures at a central SAGD plant and minimize the proportion at a SAGD satellite plant.

While existing SAGD satellite production plants do have the advantages described above, there is a need for satellite production plants that operate using a more efficient process. By creating SAGDOX satellite production plants, production and efficiency is increased costs are reduced.

SUMMARY OF THE INVENTION

The following terms and acronyms are used herein:
CAPP—Canadian Association of Petroleum Producers
SAGD—Steam Assisted Gravity Drainage
SAGDOX—SAGD with Oxygen
PAC—Petroleum Technology Alliance of Canada
NEB—National Energy Board (Canada)
OTSG—Once Through Steam Generator
EOR—Enhanced Oil Recovery
SAGDOX (xx)—SAGDOX with xx % oxygen in the steam/oxygen mix (v/v)
SAGDOX (35)—SAGDOX with 35% oxygen in the steam/oxygen mix (v/v)
ASU—Air Separation Unit
ETOR—Energy to oil ratio (MMBTU/bbl)
SOR—Steam to Oil Ratio (bbl/bbl)
CSS—Cyclic Steam Stimulation
DOE—Department of Energy (USA)
CHUA—Canada Heavy Oil Association
MIT—Mass. Institute of Technology
O/W—Oil in Water (emulsion)
W/O—Water in Oil (emulsion)
HTO—High Temperature Oxidation)(150-300°
bbl-barrel
bbls-barrels
For the purpose of the invention, bitumen is defined as an in situ hydrocarbon with <10 API gravity and >100,000 cp. in-situ viscosity. Preferably for SAGDOX, steam and oxygen are injected separately and continuously. The steam and oxygen rates are controlled to meet oxygen/steam (v/v) ratio targets and to meet energy injection targets. The produced gas removal rate is adjusted to control pattern pressures and to control and/or improve oxygen conformance. The produced fluid (bitumen and water) production rate uses steam trap control, assuming the region around the production well is steam-saturated.
Also for convenience SAGDOX is labeled as SAGDOX (A), where A is the (v/v) percent of oxygen in the oxygen and steam injectant gas). We have assessed our cases in our US patent application US 2013/0098603, herein incorporated by reference, for a range of oxygen concentrations from 5% (v/v) to 50% (v/v).
Further, in the present invention, satellite plant, satellite facility, and satellite site are used interchangeably. Also, central plant, central facility, and central site are used interchangeably.
The present invention relates to a satellite production process for bitumen recovery that either uses SAGDOX or converts an existing SAGD satellite plant to a SAGDOX satellite plant.
SAGDOX is a bitumen enhanced oil recovery (EOR) process. The process may be considered as a hybrid of SAGD and in-situ combustion (ISC). SAGDOX is described, in detail, in US2013/0098603. While similar to SAGD, SAGDOX incorporates extra vertical wells (or segregated injection/production) to inject oxygen into the system and to remove non-condensable combustion gases from the system. SAGDOX adds energy to the bitumen reservoir by direct steam injection and oxygen combustion of residual bitumen. Many of the advantages of the present invention stem from the properties of oxygen versus steam for adding heat to the reservoir.
According to one aspect of the invention, there is provided a SAGDOX satellite system for recovering hydrocarbons, the system comprises a central SAGDOX site, at least one SAGDOX satellite site remote said central SAGDOX site, and a pipeline corridor for communication between the central SAGDOX site and the SAGDOX satellite site, preferably the distance between the central site and satellite site ranges from 9 km to 160 km, more preferably 10 km to 100 km, wherein the satellite system is designed to recover hydrocarbons using a SAGDOX process at the SAGDOX satellite site and transfer recovered hydrocarbons to the central SAGDOX site.
Preferably, the central SAGDOX site comprises:

- (a) an oil/water separation unit,
- (b) an oil collection unit,
- (c) a water treatment unit, and
- (d) an oxygen generation unit.

Preferably, the SAGDOX satellite site comprises:

- (a) a boiler for steam generation,
- (b) at least one steam injection well,
- (c) at least one oxygen injection well, and
- (d) a bitumen recovery well.

Preferably, the pipeline corridor comprises:

- (a) an oxygen supply pipe to supply the SAGDOX satellite site
- (b) a treated water supply pipe to supply the SAGDOX satellite site
- (c) a natural gas supply pipe to supply the SAGDOX satellite site, and
- (d) a bitumen and water recovery pipe.

In a preferred embodiment, while the oxygen, water and natural gas are supplied to the SAGDOX satellite site; oxygen with generated steam is injected into an underground formation; and recovered from the underground formation bitumen emulsion, preferably O/W emulsions, are pumped back to the central site, then the bitumen is separated from the water, and treated water is sent back to the satellite site for steam generation.
Preferably the recovered bitumen emulsion is further combined with a chemical stabilizer or diluent at the SAGDOX satellite site, and the pipeline corridor further comprises a pipe for delivering said chemical stabilizer or diluent to the SAGDOX satellite site.
Preferably the SAGDOX satellite site further comprises a vent gas treating unit for sequestering CO₂and/or other produced gases.
Preferably each central SAGDOX plant has more than one SAGDOX satellite plants attached to it with one or more pipeline corridors.
Preferably at the SAGDOX satellite plant, the oxygen and generated steam are injected into said underground formation in one of the following ways: 1) the oxygen with generated steam are simultaneously injected into the same well; 2) the oxygen with generated steam are simultaneously injected into several wells; 3) or the oxygen and generated steam are separately injected into separated wells for steam and oxygen and the mixture takes place in the underground formation.
Preferably oxygen in the oxygen and generated steam mixture has a concentration in range of 5% to 50% (v/v), preferably 10% to 40% (v/v), more preferably the concentration is about 35% (v/v).
According to another aspect of the invention, there is provided a process of upgrading an existing SAGD facility by transforming it into an SAGDOX satellite system, the process comprising: installation of an oxygen generation unit at the central SAGD facility, providing at least one remotely located SAGDOX satellite site, preferably a plurality of SAGDOX satellite sites, and providing at least one pipeline corridor, preferably a plurality of pipeline corridors, between the central SAGD facility and the SAGDOX satellite site. Preferably said pipeline corridor further comprising additional pipelines for oxygen supply, produced water and natural gas supply; thus increasing the operational area of the original facility for bitumen recovery by minimizing capital cost.
According to yet another aspect of the invention, there is provided a process for recovering bitumen from a satellite bitumen production site and delivering bitumen to a central facility, whereby:

- (a) the satellite bitumen production site is remote said central facility, preferably said satellite bitumen production site is located more than 10 km from the central facility,
- (b) a pipeline corridor is provided for linking the satellite bitumen production site and the central facility, preferably said corridor further comprises at least one pipeline to provide treated water, suitable for boiler use, from the central site; at least one pipeline to provide oxygen gas from the central facility to the satellite bitumen production site, for SAGDOX; and at least one pipeline to provide produced fluids (bitumen and water) to the central facility recovered from the satellite bitumen production site. Preferably, the process used for recovering bitumen from a satellite bitumen production site is SAGDOX as described herein.

Preferably, the produced fluids (bitumen and water) are conveyed from the satellite bitumen production site to the central facility in a push-water system.
Preferably, the produced fluids (bitumen and water) are conveyed to the central plant as a stabilized emulsion. Preferably said stabilized emulsion comprises a chemical stabilizer, such as ethoxylated nonylphenol, preferably added to the produced fluids (bitumen and water) at the satellite bitumen production site.
Preferably a diluent is blended with the produced fluids (water and bitumen) for transport to the central facility.
Preferably, natural gas or fuel gas is also provided to the satellite bitumen production site, from the central facility by the pipeline corridor, for use as a boiler fuel.
Preferably, electricity is also transported from the central facility to/from the satellite bitumen recovery site.
Preferably, a produced gas (CO₂) pipeline is added to convey SAGDOX vent gas from the satellite bitumen recovery site to the central facility.
According to another aspect of the invention an existing SAGD satellite bitumen recovery site with existing steam capacity, is converted to a SAGDOX satellite site, as defined herein, utilizing existing steam capacity at the SAGD satellite bitumen recovery site.
According to another aspect of the invention, produced water is separated at the satellite bitumen recovery site, preferably this water is either treated for boiler use or disposed of on-site, wherein the diluted bitumen, is conveyed back to the central facility generally free from excess water.
More specifically, the present invention, a SAGDOX production satellite plant has the following advantages:
1. The SAGDOX satellite plant is greater than 9 km, more preferably 15 km, distance from SAGDOX central plant because oxygen can be economically pipelined for approximately 100 miles. This is more than 10 times steam's limit of approx. 10 km.
2. SAGDOX satellite site reduces capital expenditures at the satellite site (greenfield) for the pipeline corridor and for the overall project. Most of the expenditures for major process elements are at the central facility. Specifically, pipeline corridor costs for SAGDOX are 22% less; boiler costs can be reduced by 85%.
3. If vent gas (mostly CO₂) is captured or sequestered on site, either at satellite plant, central plant, or both), emissions per unit bitumen produced are significantly reduced.
4. As shown in US 2013/0098603, the process efficiency when incorporating SAGDOX satellite site is improved compared to SAGD satellite site. If efficiency is measured as the energy produced (in bitumen) compared to the energy used, on the surface, to produce the energy, then SAGDOX is a much more efficient process than SAGD.
5. Water use is minimized. As shown in US 2013/0098603, if SAGDOX produces connate water, make-up water can be reduced and/or eliminated to the central plant. Specifically, SAGDOX can also produce water directly from combustion and by vaporizing connate water, so that no new make-up water is needed.
6. The steam and oxygen mixture has a preferred oxygen concentration range (5 to 50% (v/v)) This preferred range for SAGDOX has minimum and maximum oxygen/steam ratios, with the following rationale:

- a. The minimum oxygen/steam ratio is 0.05 (v/v) (oxygen concentration of about 5%) Below this concentration, the following occurs:
  - i. HTO combustion starts to become unstable. It becomes more difficult to attain minimum oxygen flux rates to sustain HTO, particularly for a mature SAGDOX process where the combustion front is far away from the injector.
  - ii. It also becomes difficult to vaporize and mobilize all connate water.
- b. The maximum oxygen/steam ratio is 1.00 (v/v) (oxygen concentration of 50.0%). Above this concentration, the following occurs:
  - i. The reflux rates in the reservoir to sustain steam inventories exceed 70% of the total steam. This may be difficult to attain in practice.
  - ii. The net bitumen (“coke”) fuel that is consumed by oxidation starts to exceed the residual fuel left behind in the SAGD steam-swept zone. So compared to SAGD, SAGDOX (50+) may have lower recoveries and reserves.
  - v. Above this limit it becomes difficult to produce steam and oxygen from an integrated ASU: Cogen plant.

So the preferred range for oxygen/steam ratios is 0.05 to 1.00 (v/v) corresponding to a concentration range of 5 to 50% (v/v) of oxygen in the mix.
7. Total capex costs are also less. Per unit energy delivered to the reservoir, oxygen capex is much less than steam and water treating capex.
8. Economies of scale for air separation unit (ASU) oxygen plants at reasonable sizes for SAGDOX satellites have been achieved. For a 25 KBD SAGDOX (35) satellite 2000 tonnes/day of oxygen is needed. This is a nice fit both for the capacity of the satellite and the capacity of the ASU plant.
9. The SAGDOX process of the present invention produces an off-gas in one embodiment that is almost substantially pure CO₂. In one embodiment, if this off-gas is captured for sequestration, CO₂emissions in SAGDOX can be much less than SAGD.
10. At first blush, it may appear SAGDOX needs more wells than SAGD—to inject oxygen gas and to remove produced non-condensable gases. However, SAGDOX allows longer horizontal wells to be drilled, by reducing hydraulic limits on horizontal well lengths. So, on a per-unit-volume-of-reservoir basis, SAGDOX well costs can be comparable to or less than SAGD well costs.
11. SAGDOX opex costs are less than SAGD. The wells can be operated longer and reservoirs increased.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 depicts a typical SAGDOX process

FIG. 2 depicts a 10 KBD (thousand barrels per day) Satellite SAGD

FIG. 3 depicts a 10 KBD Satellite SAGDOX (10)

FIG. 4 depicts a 10 KBD Satellite SAGDOX (9)

FIG. 5 depicts a 10 KBD Satellite SAGDOX (20)

FIG. 6 depicts a 10 KBD Satellite SAGDOX (35)

FIG. 7 depicts a 10 KBD Satellite SAGDOX (50)

FIG. 8 depicts an Expansion to an Existing 10 KBD SAGD Satellite SAGDOX (5) Increment

FIG. 9 depicts an Expansion to an Existing 10 KBD SAGD Satellite SAGDOX 9 Increment

FIG. 10 depicts an Expansion to an Existing 10 KBD SAGD Satellite SAGDOX (20) Increment

FIG. 11 depicts an Expansion to an Existing 10 KBD SAGD Satellite SAGDOX (35) Increment

FIG. 12 depicts an Expansion to an Existing 10 KBD SAGD Satellite SAGDOX (50) Increment

FIG. 13 depicts Viscosity versus % disperse phase of O/W Emulsions

FIG. 14 depicts a central SAGDOX plant connected to more than one satellite SAGDOX plant

DETAILED DESCRIPTION OF THE INVENTION

Referring now to FIG. 1, a typical geometry of the SAGDOX system of the present invention is depicted. As can be seen, oxygen 5 is added during the SAGD process through the steam pipeline 1 and the effluents include produced gas 4 as well as bitumen and water 2.
Referring now to FIG. 2, there is depicted a SAGD system in which a SAGD central plant is connected to a SAGD satellite site. In this instance, a set-up consists of pipelines running from the base plant 10 to the satellite site 20. A series of pipelines connect the base plant 10 with the satellite site 20. In particular, treated water is provided to satellite site 20 via pipeline 30. Diluent is provided to satellite site 20 via pipeline 40. Natural gas fuel to fuel the boiler in the satellite site is provided to the satellite site via pipeline 50. Finally, pipeline 60 is provided to transport the mixture of diluent+produced water+bitumen from the satellite site 20 to the central plant 10. In this set-up, 33.7 KBD of treated water 30 is needed for the SAGD operation at the satellite site (namely for steam production); Boiler CO₂is 14.8 MMSCFD; 14.8 MMSCFD of natural gas fuel 50 is needed to fuel the boiler; 3.37 KBD of make-up water 75 is needed at the base plant; and diluent+produced water+bitumen 120 product pipeline volume of 53.7 KBD. Further in this instance, characteristics include: 1) the ETOR is 1.8; 2) SOR is 3.37; 3) the OTSG is 80% efficient; 4) steam is at 1000 BTU/lb; 5) 90% of produced water that goes to central plant is recycled as steam; 6) 10 KBD bitumen 95 increment; 7) all steam injected equals produced water; and 8) natural gas fuel at 1000 BTU/SCF; and 9) diluent/bitumen ratio equal 1.0.
Referring now to FIG. 3, there is depicted a SAGDOX satellite system of the present invention wherein central plant 10 is connected to a SAGDOX satellite site 20. One major difference between the system of FIG. 1 and the system of FIG. 2 is the additional Oxygen pipeline 45 from the base plant 10 to feed oxygen to the SAGDOX satellite site 20. In this system, the percentage of oxygen in the steam/oxygen mixture is 5 whereas in the system of FIG. 1 there is no oxygen. As can readily be seen, 8.56 MMSCFD or 327 tonnes/d of oxygen 45 is delivered to the SAGDOX satellite plant 20; vent pure CO ₂105 is 8.56 MMSCFD; natural gas fuel 51 from the base plant 10 to the satellite is 9.6 MMSCFD; Diluent+produce water+bitumen 121 is 42.0 KBD; treated water 31 is 22.0 KBD; Make up water 76 is 2.2 KBD; disposal water 86 is 2.2 KBD; ASU electricity 60 is 4.0 MW versus zero in FIG. 2; and boiler CO ₂111 is 9.6 MMSCFD. Further in this instance, characteristics include: 1) the ETOR is 1.8; 2) the OTSG is 80% efficient; 3) steam is at 1000 BTU/lb.; 4) oxygen is at 480 BTU/SCF; 5) 90% of produced water that goes to central plant is recycled as steam; 6) 10 KBD bitumen 95 increment; 7) all steam injected equals produced water; 8) no extra water; 9) 292.5 kWh/tonne Oxygen (95-97% purity); 10) natural gas fuel at 1000 BTU/SCF; 11) diluent/bitumen ratio equal 1.0; and 12) pure carbon dioxide vent gas equals the oxygen used.
Referring now to FIG. 4, there is depicted a SAGDOX satellite system of the present invention wherein central plant 10 is connected to a SAGDOX satellite plant 20. In this system, the percentage of oxygen in the steam/oxygen mixture is 9. In this instance 12.3 MMSCFD or 421 tonnes/d of oxygen 46 is delivered to the satellite; vent pure CO ₂106 is 12.3 MMSCFD; natural gas fuel 52 from the central plant 10 to the satellite plant is 7.38 MMSCFD; Diluent+produce water+bitumen 122 is 36.9 KBD; treated water 32 is 16.9 KBD; Make up water 77 is 1.7 KBD; disposal water 87 is 1.7 KBD; ASU electricity 61 is 5.1 MW; and boiler CO ₂112 is 7.38 MMSCFD. Further in this instance, characteristics include: 1) the ETOR is 1.8; 2) the OTSG is 80% efficient; 3) steam is at 1000 BTU/lb; 4) Oxygen is at 480 BTU/SCF; 5) 90% of produced water that goes to central plant is recycled as steam; 6) 10 KBD bitumen 95 increment; 7) all steam injected equals produced water; 8) no extra water; 9) 292.5 kWh/tonne Oxygen (95-97% purity); 10) natural gas fuel at 1000 BTU/SCF; 11) diluent/bitumen ratio equal 1.0; and 12) pure carbon dioxide vent gas equals the oxygen used.
Referring now to FIG. 5, there is depicted a SAGDOX satellite system of the present invention wherein central plant 10 is connected to a SAGDOX satellite plant 20. In this system the percentage of oxygen in the steam/oxygen mixture is 20. In this instance 17.6 MMSCFD or 672 tonnes/d of oxygen 47 is delivered to the satellite; vent pure CO₂107i s 17.6 MMSCFD; natural gas fuel 53 from the base plant 10 to the satellite is 4.17 MMSCFD; Diluent+produce water+bitumen 123 is 29.54 KBD; treated water 33 is 9.54 KBD; Make up water 78 is 0.95 KBD; disposal water 88 is 0.95 KBD; ASU electricity 62 is 8.1 MW; and boiler CO ₂113 is 4.17 MMSCFD. Further in this instance, characteristic include: 1) the ETOR is 1.8; 2) the OTSG is 80% efficient; 3) steam is at 1000 BTU/lb; 4) oxygen is at480 BTU/SCF; 5) 90% of produced water that goes to central plant is recycled as steam; 6) 10 KBD bitumen 95 increment; 7) all steam injected equals produced water; 8) No extra water; 9) 292.5 kWh/tonne Oxygen (95-97% purity); 10) natural gas fuel at 1000 BTU/SCF; 11) diluent/bitumen ratio equal 1.0; and 12) pure carbon dioxide vent gas equals the oxygen used.
Referring now to FIG. 6, there is depicted a SAGDOX satellite system of the present invention wherein central plant 10 is connected to a SAGDOX satellite plant 20. In this system, the percentage of oxygen in the steam/oxygen mixture is 35. In this instance, 20.8 MMSCFD or 794 tonnes/d of oxygen 48 is delivered to the satellite; vent pure CO ₂108 is 20.8 MMSCFD; natural gas fuel 54 from the central plant 10 to the satellite plant 20 is 2.28 MMSCFD; Diluent+produce water+bitumen 124 is 25.2 KBD; treated water 34 is 5.2 KBD; Make up water 79 is 0.5 KBD; disposal water 89 is 0.5 KBD; ASU electricity 63 is 9.7 MW; and boiler CO ₂114 is 2.28 MMSCFD. Further in this instance, characteristics include: 1) the ETOR is 1.8; 2) the OTSG is 80% efficient; 3) steam is at 1000 BTU/lb 4) oxygen is at480 BTU/SCF; 5) 90% of produced water that goes to central plant is recycled as steam; 6) 10KBD bitumen 95 increment; 7) all steam injected equals produced water; 8) no extra water; 9) 292.5 kWh/tonne Oxygen (95-97% purity); 10) natural gas fuel at 1000 BTU/SCF; 11) diluent/bitumen ratio equal 1.0; and 12) pure carbon dioxide vent gas equals the oxygen used.
Referring now to FIG. 7, there is depicted a SAGDOX satellite system of the present invention wherein central plant 10 is connected to a SAGDOX satellite plant 20. In this system the percentage of oxygen in the steam/oxygen mixture is 50. In this instance 22.4 MMSCFD or 855 tonnes/d of oxygen 49 is delivered to the satellite 20; vent pure CO ₂109 is 22.4 MMSCFD; natural gas fuel 55 from the central plant 10 to the satellite 20 is 1.32 MMSCFD; Diluent+produce water+bitumen 125 is 23.0 KBD; treated water 35 is 3.0 KBD; Make up water 80 is 0.3 KBD; disposal water 90 is 0.3 KBD; ASU electricity 64 is 10.4 MW; and boiler CO ₂115 is 1.32 MMSCFD. Further in this instance, characteristics include: 1) the ETOR is 1.8; 2) the OTSG is 80% efficient; 3) steam is at 1000 BTU/lb 4) oxygen is at 480 BTU/SCF; 5) 90% of produced water that goes to central plant is recycled as steam; 6) 10 KBD bitumen 95 increment; 7) all steam injected equals produced water; 8) no extra water; 9) 292.5 kWh/tonne Oxygen (95-97% purity); 10) natural gas fuel at 1000 BTU/SCF; 11) diluent/bitumen ratio equal 1.0; and 12) pure carbon dioxide vent gas equals the oxygen used.
As seen in FIGS. 2 through 7, the amount of diluent 40 introduced to the satellite 20 remained constant at 10 KBD.
Referring now to FIG. 8, there is depicted an expansion of an existing 10 KBD SAGD system to a SAGDOX satellite system of the present invention wherein central plant 10 is connected to a SAGDOX satellite plant 20 and all the steam capacity at the existing satellite is used, which means no natural gas fuel is required to be pipelined to the satellite. In this system the percentage of oxygen in the steam/oxygen mixture is 5. In this instance 13.13 MMSCFD of oxygen 140 is delivered to the satellite; vent pure CO ₂160 is 13.13 MMSCFD; diluent 41 from the central plant 10 to the satellite plant 20 is 5.34 KBD; Diluent+produce water+bitumen 126 is 16.02 KBD; incremental bitumen 96 is 5.34 KBD; treated water is 0.0 KBD; Make up water 35 is 0.0 KBD; disposal water 91 is 0.0 KBD; ASU electricity 65 is 6.11 MW; and boiler CO ₂116 is 0.0 MMSCFD. Further in this instance, characteristics include: 1) the ETOR is 1.8; 2) the OTSG is 80% efficient; 3) steam is at 1000 BTU/lb; 4) oxygen is at 480 BTU/SCF; 5) 90% of produced water that goes to central plant is recycled as steam; 6) all steam injected equals produced water; 7) No extra water; 8) 292.5 kWh/tonne Oxygen (95-97% purity); 9) natural gas fuel at 1000 BTU/SCF; 10) diluent/bitumen ratio equal 1.0; 10) pure carbon dioxide vent gas equals the oxygen used; and 11) all steam capacity at existing satellite is used.
Referring now to FIG. 9, there is depicted an expansion of an existing 10 KBD SAGD system to a SAGDOX satellite system of the present invention wherein central plant 10 is connected to a SAGDOX satellite plant 20 and all the steam capacity at the existing satellite is used, which means no natural gas fuel is required to be pipelined to the satellite plant 20. In this system, the percentage of oxygen in the steam/oxygen mixture is 9. In this instance, 24.6 MMSCFD of oxygen 141 is delivered to the satellite 20; vent pure CO ₂161 is 24.6 MMSCFD; diluent 40 from the central plant 10 to the satellite plant 20 is 10.0 KBD; Diluent+produce water+bitumen 127 is 30.0 KBD; incremental bitumen 95 is 10.0 KBD; treated water 35 is 0.0 KBD; Make up water is 81 0.0 KBD; disposal water 91 is 0.0 KBD; ASU electricity 66 is 11.5 MW; and boiler CO ₂116 is 0.0 MMSCFD. Further in this instance, characteristics include: 1) the ETOR is 1.8; 2) the OTSG is 80% efficient; 3) steam is at 1000 BTU/lb; 4) oxygen is at 480 BTU/SCF; 5) 90% of produced water that goes to central plant is recycled as steam; 6) all steam injected equals produced water; 7) No extra water; 8) 292.5 kWh/tonne Oxygen (95-97% purity); 9) natural gas fuel at 1000 BTU/SCF; 10) diluent/bitumen ratio equal 1.0; 10) pure carbon dioxide vent gas equals the oxygen used; and 11) all steam capacity at existing satellite is used.
Referring now to FIG. 10, there is depicted an expansion of an existing 10 KBD SAGD system to a SAGDOX satellite system of the present invention wherein central plant 10 is connected to a SAGDOX satellite site 20 and all the steam capacity at the existing satellite is used, which means no natural gas fuel is required to be pipelined to the satellite. In this system the percentage of oxygen in the steam/oxygen mixture is 20. As can readily be seen, in this instance 62.0 MMSCFD of oxygen 142 is delivered to the satellite; vent pure CO ₂162 is 62.2 MMSCFD; diluent 42 from the central plant 10 to the satellite plant 20 is 25.34 KBD; Diluent+produce water+bitumen 128 is 76.02 KBD; incremental bitumen 97 is 25.34 KBD; treated water 35 is 0.0 KBD; Make up water 81 is 0.0 KBD; disposal water 91 is 0.0 KBD; ASU electricity 67 is 29.0 MW; and boiler CO₂116i s 0.0 MMSCFD Further in this instance, characteristics include: 1) the ETOR is 1.8; 2) the OTSG is 80% efficient; 3) steam is at 1000 BTU/lb; 4) oxygen is at 480 BTU/SCF; 5) 90% of produced water that goes to central plant is recycled as steam; 6) all steam injected equals produced water; 7) No extra water; 8) 292.5 kWh/tonne Oxygen (95-97% purity); 9) natural gas fuel at 1000 BTU/SCF; 10) diluent/bitumen ratio equal 1.0; 10) pure carbon dioxide vent gas equals the oxygen used; and 11) all steam capacity at existing satellite is used.
Referring now to FIG. 11, there is depicted an expansion of an existing 10 KBD SAGD system to a SAGDOX satellite system of the present invention wherein central plant 10 is connected to a SAGDOX satellite plant 20 and all the steam capacity at the existing satellite is used, which means no natural gas fuel is required to be pipelined to the satellite. In this system the percentage of oxygen in the steam/oxygen mixture is 35. As can readily be seen, in this instance 134.2 MMSCFD of oxygen 143 is delivered to the satellite plant 20; vent pure CO ₂163 is 134.2 MMSCFD; diluent 43 from the central plant 10 to the satellite plant 20 is 54.52 KBD; Diluent+produce water+bitumen 129 is 163.56 KBD; incremental bitumen 98 is 54.52 KBD; treated water 35 is 0.0 KBD; Make up water 81 is 0.0 KBD; disposal water 91 is 0.0 KBD; ASU electricity 68 is 62.5 MW; and boiler CO ₂116 is 0.0 MMSCFD Further in this instance, characteristics include: 1) the ETOR is 1.8; 2) the OTSG is 80% efficient; 3) steam is at 1000 BTU/lb; 4) oxygen is at 480 BTU/SCF; 5) 90% of produced water that goes to central plant is recycled as steam; 6) all steam injected equals produced water; 7) No extra water; 8) 292.5 kWh/tonne Oxygen (95-97% purity); 9) natural gas fuel at 1000 BTU/SCF; 10) diluent/bitumen ratio equal 1.0; 10) pure carbon dioxide vent gas equals the oxygen used; and 11) all steam capacity at existing satellite is used.
Referring now to FIG. 12, there is depicted an expansion of an existing 10 KBD SAGD system to a SAGDOX satellite system of the present invention wherein central plant 10 is connected to a SAGDOX satellite plant 20 and all the steam capacity at the existing satellite is used, which means no natural gas fuel is required to be pipelined to the satellite. In this system the percentage of oxygen in the steam/oxygen mixture is 50. In this instance 248.9 MMSCFD of oxygen 144 is delivered to the satellite plant 20; vent pure CO ₂164 is 248.9 MMSCFD; diluent 44 from the central plant 10 to the satellite 20 is 101.11 KBD; Diluent+produce water+bitumen 130 is 303.3 KBD; incremental bitumen 98 is 101.11 KBD; treated water 35 is 0.0 KBD; Make up water 81 is 0.0 KBD; disposal water 91 is 0.0 KBD; ASU electricity 68 is 115.9 MW; and boiler CO ₂116 is 0.0 MMSCFD. Further in this instance, characteristics include: 1) the ETOR is 1.8; 2) the OTSG is 80% efficient; 3) steam is at 1000 BTU/lb; 4) oxygen is at 480 BTU/SCF; 5) 90% of produced water that goes to central plant is recycled as steam; 6) all steam injected equals produced water; 7) No extra water; 8) 292.5 kWh/tonne Oxygen (95-97% purity); 9) natural gas fuel at 1000 BTU/SCF; 10) diluent/bitumen ratio equal 1.0; 10) pure carbon dioxide vent gas equals the oxygen used; and 11) all steam capacity at existing satellite is used.
Referring now to FIG. 14, there is depicted a SAGDOX central plant 10 connected to more than one SAGDOX satellite plant 20. A pipeline corridor connects the SAGDOX central plant 10 to each SAGDOX satellite plant 20, allowing for communication between the central SAGDOX plant 10 and the SAGDOX satellite plant 20.
Table 2 provides the typical injection gas properties of SAGDOX for the different oxygen concentrations in steam and oxygen mixtures discussed above, according the present invention.
SAGDOX (35) is the preferred embodiment of the process. SAGDOX (35) is depicted in FIG. 6 with the following properties:

- 1. An oxygen/steam flow ratio of 0.538 (v/v).
- 2. 84.5% of the heat stems from oxygen (combustion).
- 3. Per SCF of mix, the heat delivery is 199 BTU.
- 4. To deliver 1 MMBTU of energy, we need 5 MSCF of gases (steam and O₂).

Comparing FIG. 2 (SAGD) to FIG. 6 (SAGDOX (35)), the following advantages are seen:

- 1. Reduction in steam boiler capacity at the satellite site from 33.7 to 5.2 KBD steam—85% reduction.
- 2. Reduction in fuel gas demand from 14.8 MMSCFD to 2.3 MMSCFD—85% reduction.
- 3. Reduction of product pipeline volume from 53.7 to 25.2 KBD—53% reduction. A similar reduction in incremental oil/water separation capacity is expected.
- 4. Reduction in treated water supply similar to steam—85% reduction. Equivalent reduction in incremental water treatment capacity is expected.
- 5. Reduction in disposal water and make-up water from 3.4 KBD to 0.5 KBD—85% reduction.
- 6. Diluent supply is unaffected.
- 7. If pure CO₂is captured and sequestered, CO₂emissions will be reduced from 14.8 to 2.3 MMSCFD—an 85% decrease (some of the capture benefit can be realized if CO₂is sequestered/retained in the bitumen reservoir).

Preferably, the satellite plant is more than 10 km from the central plant, otherwise it would be economic to integrate the satellite and supply steam from a central site. Also, the pipeline corridor, between the satellite site and the central plant site, should contain the following fluids pipelines:

- 1. Treated water, from the central site.
- 2. Oxygen gas for SAGDOX, from the central site.
- 3. Produced water and bitumen, from the satellite site.

Also preferably, it may be feasible to pipeline produced fluids, without diluent using push water systems as discussed above. Fuel gas may be available from an alternate source, such as local supplies from pipelines or gas wells. For some cases, as listed below, the pipeline corridor may also contain the following fluid pipelines:

- 1. Natural gas boiler fuel, from the central site.
- 2. Diluent, from the central site.
- 3. A produced fluid pipeline including diluent, from the satellite site.
- 4. A CO₂vent gas pipeline, from the satellite site.

Further explaining the advantages of SAGDOX, the cost of the pipeline corridor for SAGDOX satellites is less than SAGD satellites in all embodiments. Assuming installed cost of pipelines is proportional to pipeline diameter, Table 7 summarizes diameters and cumulative diameters for each case assuming a 5 ft/sec velocity (3.4 mph) for liquids and 50 ft/sec for gases at 500 psia (this is within the safe operating region for oxygen in carbon steel pipelines (Sarathi, P. S., In-Situ Combustion Handbook, DOE, 1996). For our preferred case, SAGDOX (35), the capital cost of the pipeline corridor is 22% less than the cost for the SAGD case.
Table 11 highlights a SAGDOX advantage as well. If we pipeline an O/W emulsion from the satellite plant to the central plant, rather than an oil and diluent and water mix, the advantage of the SAGDOX satellite c/w SAGD is even more pronounced.
Even further, assuming a 2000 tonne/day ASU oxygen train, at the central plant, to capture the economy-of-scale for oxygen production, Table 4 shows the minimum satellite project size to capture these savings. The size varies from 61 KBD for SAGDOX (5) to 23 KBD for SAGDOX (50). For our preferred case, SAGDOX (35), the minimum satellite size is 25 KBD.
Referring to Table 3, considerable boiler cost savings when using SAGDOX are highlighted. For example, for a 10 KBD satellite our satellite site boiler capacities and savings are as follows:


MMBTU/hr	% SAGD	% Savings

SAGD	492	100	0
SAGDOX(5)	320	65	35
SAGDOX(9)	246	50	50
SAGDOX(20	139	28	72
SAGDOX(35)	76	15	85
SAGDOX(50)	44	9	91

If we don't add diluent at the satellite site we may have to add shear to produce an oil in water (O/W) emulsion that will be stable until it reaches the central facility. Alternately, we can add an emulsion stabilizer (surfactant) so that we can pipeline the product safely. The viscosity of O/W emulsions is relatively independent of the oil viscosity and low enough to pipeline directly (FIG. 13).
Also, the option with the minimum capex at the satellite site and for the satellite pipeline corridor includes the following elements:

- 1. SAGDOX (50) EOR process at the satellite site.
- 2. Pipeline for bitumen and produced water as an O/W emulsion, using mechanical stirring at the satellite and addition of a stabilizer/surfactant if necessary.
- 3. Procurement of fuel gas for boilers from another source, rather than provision of a separate line from the central facility. The same for electrical supply.
- 4. Expanded water treatment, oil/water separation, oxygen production, and tankage at the central facility.
- 5. Size the expansion large enough to capture economies of scale.

Based on the above, the following can be concluded:

- 1. The capacity increment, to the 10 KBD satellite plant, varies from 15 KBD for SAGDOX (5) to 111 KBD for SAGDOX (50). Our preferred case (SAGDOX (35)) results in a production increment of 64.5 KBD (Table 8).
- 2. For the expansion increments, oxygen demands vary from 501 tonnes/d for SAGDOX (5) up to 9510 tonnes/d for SAGDOX (50). Our preferred case (SAGDOX (35)) has an oxygen demand of 5128 tonnes/d—large enough to capture economy of scale for ASU oxygen production.
- 3. On a per-bbl-of-bitumen basis (Table 9), our SAGDOX increments produce only one third the volume of produced fluids (including diluent) compared to our SAGD satellite or a SAGD increment. No extra water is used at all. The increment is pure combustion based.
- 4. Also on a per-bbl-of-bitumen basis, without capture of a near-pure vent gas CO₂, CO₂emissions are 66% per bbl more incremental bitumen. If the vent gas is captured or retained in the reservoir, the incremental bitumen production has no associated CO₂emissions.

Also discussed above, the SAGDOX option for a new satellite plant has at least one additional pipeline compared to SAGD—the oxygen line to deliver oxygen to the satellite site. But, other lines can have significant reduced capacity (FIGS. 2 to 7). Table 6 summarizes the individual volumes for each SAGD and SAGDOX case for a 10 KBD satellite plant. SAGDOX, for all cases, has a reduced liquids capacity but an increased gas capacity.
If we are expanding an existing SAGD satellite, it is particularly advantageous to switch to SAGDOX, because:

- 1. We need not expand/construct any additional boilers, treated water pipelines, water treatment capacity or fuel gas supply pipelines.
- 2. The SAGDOX increments can be quite large—up to 111 KBD increment based on an existing 10 KBD SAGD satellite.

FIGS. 8, 9, 10, 11, & 12 and Tables 8 & 9 show an analysis of a SAGDOX expansion to a 10 KBD SAGD satellite, assuming the existing steam capacity at the satellite is used to supply the steam for SAGDOX, and the size of the expansion is adjusted to consume all the steam for a range of steam and oxygen mixes from 5 to 50% (v/v) oxygen. On an incremental basis, no additional capacity for steam generation and water treatment or new pipeline capacity for treated water supple and fuel gas is needed. This simplifies capital expenditures and the pipeline corridor expansion.
Table 10 summarizes the capex item differences at the satellite site and central site when comparing SAGD with SAGDOX, as well as some of the advantages of the present invention.
Other embodiments of the invention will be apparent to a person of ordinary skill in the art and may be employed by a person of ordinary skill in the art without departing from the spirit of the invention.

TABLE 1

Canadian Steam EOR Production

	March 2011 (KBD)

	SAGD
	Cenovus (Foster Creek)	118.7
	Suncor (Finebag)	53.9
	Devon (Jackfish)	31.8
	Suncor (Mackay)	31.2
	Meg (Christina LK)	37.2
	Nexen (Long LK)	26.2
	Conoco Phillips (Surmont)	22.3
	Others	47.8
	SAGD Total	359.0
	CSS
	Imperial Oil (Cold Lake)	162.0
	Can. Nat. (Primrose/Wolf Lk)	77.2
	Others	5.1
	CSS Total	244.3
	Canada Total	603.3

	Source:
	1. First Energy Capital. Jun. 9, 2011

TABLE 2

SAGDOX Injection Gas Properties
% Oxygen in Steam and O₂Mixes (v/v)

	0	5	9	20	35	50

% heat from O₂	0.0	34.8	50.0	71.7	84.5	91.0
% heat from steam	100.0	65.2	50.0	28.3	15.5	9.0
BTU/SCF mix	47.4	69.0	86.3	133.9	198.8	263.7
MSCF/MMMBTU mix	21.1	14.5	11.6	7.5	5.0	3.8
MSCF O₂/MMBTU mix	0.0	0.7	1.0	1.5	1.8	1.9
MSCF stm/MMBTU mix	21.1	13.8	10.6	6.0	3.3	1.9

Where:
1. Steam = 1000 BTU/lb
2. Oxygen = 480 BTU/SCF (Butler (1991))
3. 0% oxygen = 100% steam (SAGD)

TABLE 3

SAGDOX Performance Factors
% Oxygen in Steam and O₂Mixes (v/v)

	0	5	9	20	35	50

Steam
% of heat	100.0	65.2	50.0	28.3	15.5	9.0
MSCF/bbl bit	24.89	16.22	12.45	7.05	3.86	2.24
SOR (bbl/bbl)	3.37	2.20	1.69	0.954	0.52	0.30
MMBTU/bbl bit	1.18	0.769	0.590	0.334	0.183	0.106
Oxygen
% of heat	0.0	34.8	50.0	71.7	84.5	91.0
MSCF/bbl bit	0.0	0.856	1.23	1.76	2.08	2.237
Tonnes/bbl bit	0.0	0.0327	0.0421	0.0672	0.0794	0.0855
MMBTU/bbl bit	0.0	0.411	0.590	0.846	0.997	1.074
Totals
ETOR (MMBTU/bbl)	1.18	1.18	1.18	1.18	1.18	1.18
Gas (MSCF/bbl)	24.89	17.08	13.68	8.81	5.94	4.48

Where:
1. Gas = oxygen and steam
2. ETOR = energy to oil ratio
3. 1000 BTU/lb steam; 489 BTU/SCF oxygen
4. 0% oxygen = 100% steam (SAGD)
5. All cases have ETOR = 1.18

TABLE 4

Economy of Scale for SAGDOX Satellites
% Oxygen in Steam and O₂Mixes (v/v)

	5	9	20	35	50

O₂for 10 KBD Bit
(MMSCFD)	8.56	12.3	17.6	20.8	22.4
(tonnes/d)	327	421	672	794	855
Bit for 2000 t/d O₂
(KBD)	61.2	47.5	29.8	25.2	23.4

Where:
1. ETOR = 1.18 for all cases
2. 2000 t/d oxygen = world scale
3. 1000 BTU/lb steam; 480 BTU/SCF O₂

TABLE 5

10,000 B/D Satellite Performance Factors
% Oxygen in Steam and O₂Mixes (v/v)

	0	5	9	20	35	50

Steam
(MMSCFD)	248.9	162.2	124.5	70.5	38.6	22.4
(MMBTU/hr)	492	320	246	139	76	44
(K bbls/d)	33.7	22.0	16.9	9.54	5.20	3.00
(SOR)	3.37	2.20	1.69	0.954	0.520	0.300
Oxygen
MMSCFD	0.0	8.56	12.3	17.6	20.8	22.4
MMBTU/hr	0.0	171	246	353	415	448
tonnes/d	0.0	327	421	672	794	855
SCF/bbl	0.0	856	1230	1760	2080	2237
Totals
Gas(MMSCFD)	248.9	171	137	88	59	45
(SCF/bbl)	24890	17100	13700	8800	5900	4500

Where:
1. 0% oxygen = 100% steam (SAGD)
2. All at ETOR = 1.18
3. gas = O₂and steam (MMSCFD)

TABLE 6

New 10 KBD Satellite Comparisons
% Oxygen in Steam and O₂mixes (v/v)

	0	5	9	20	35	50

Liquids (KBD)
Treated Water	33.7	22.0	16.9	9.5	5.2	3.0
Diluent Delivery	10.0	10.0	10.0	10.0	10.0	10.0
Dil + bit + water	53.7	42.0	36.9	29.5	25.2	23.0
Totals	97.4	74.0	63.8	49.0	40.4	36.0
% bit cut (D + B + W)	18.6	23.8	27.1	33.9	39.7	43.5
% dil + bit cut	37.2	47.6	54.2	67.8	79.4	87.0
Gases (MMSCFD)
Nat gas fuel	14.8	9.6	7.4	4.2	2.3	1.3
Oxygen	0	8.6	12.3	17.6	20.8	22.4
Totals	14.8	18.2	19.7	21.8	23.1	23.7
(KBD) Make-up Water	3.4	2.2	1.7	1.0	0.5	0.3

Where:
1. Assumptions as per FIGS. 1 to 5
2. 0% oxygen = 100% steam (SAGD)
3. ETOR = 1.18

TABLE 7

New 10KB Satellites: Pipeline Size Comparisons (D inches)
% Oxygen in Steam and O₂Mixes (v/v)

	0	5	9	20	35	50

Liquids
Treated Water	8.96	7.24	6.34	4.76	3.52	2.67
Diluent	4.88	4.88	4..88	4.88	4.88	4.88
Dil + bit + water	11.31	10.00	9.37	8.38	7.75	7.40
Total D (liq)	25.15	22.12	20.59	18.02	16.15	14.88
Gases
N. Gas fuel	4.30	3.46	3.04	2.29	1.69	1.27
Oxygen	0	3.28	3.92	4.69	5.10	5.29
Total D (Gas)	4.30	6.74	6.96	6.98	6.79	6.56
Total D	29.45	28.86	27.55	25.00	22.94	21.38
% of SAGD	100	98.	93.5	84.9	77.9	72.6

Where:
1. Assumes liquid pipelines at 5 ft./sec design
2. Gas pipelines at 500 psia pressure (34 atm) and at 50 ft./sec linear velocity
3. Dia (inches) for liquid lines = (Q/420)^1/2, where Q = bbls/d
4. Dia (inches) for gas lines = (Z/0.801)^1/2, where Z = gas capacity in MMSCFD
5. Volumes based on Table 5
6. D = pipeline diameter, inches

TABLE 8

SAGDOX Increments to Existing 10 KBD SAGD Satellite

Existing SAGD

SAGDOX Increments (% O₂)

	Base	5	9	20	35	50

Capacity
SAGDOX Inc. (KBD)	0.0	5.34	10.00	25.34	54.52	101.11
Total (KBD)	10.0	15.34	20.00	35.34	64.52	111.11
Liquids (KBD)
Treated Water	33.7	0.0	0.0	0.0	0.0	0.0
Diluent	10.0	5.34	10.00	25.34	54.52	101.11
Dil + bit + wat	53.7	10.68	20.00	50.68	109.04	202.22
Total	97.4	16.02	30.00	76.02	163.56	303.33
(bbl/bbl bit)	9.74	3.00	3.00	3.00	3.00	3.00
Gases (MMSCFD)
Nat. Gas Fuel	14.8	0.0	0.0	0.0	0.0	0.0
Oxygen	0.0	13.13	24.6	62.20	134.20	248.89
Total	14.8	13.13	24.6	62.20	134.20	248.89
(KSCF/bbl bit)	1.48	2.46	2.46	2.45	2.46	2.46
CO₂Emissions (MMSCFD)
Boiler CO₂	14.8	0.0	0.0	0.0	0.0	0.0
Vent Gas CO₂	0.0	13.13	24.6	62.20	134.20	248.89
Total	14.8	13.13	24.6	62.20	134.20	248.89
(KSCF/bbl bit)	1.48	2.46	2.46	2.45	2.46	2.46
Electricity
ASU MW (e)	0.0	6.11	11.45	28.96	62.48	115.87
(kWh/bbl bit)	0.0	27.5	27.5	27.5	27.5	27.5

Where:
1. All SAGDOX increments use all steam from base SAGD plant, with no new steam capacity at satellite
2. No extra water from SAGDOX
3. All ETOR = 1.18
4. ASU else at 292.5 kWh/tonne O ₂
5. 1 tonne O₂= 26.173 MSCF (1 MMSCF = 38.2 tonnes)

TABLE 9

Comparison SAGDOX vs. SAGD Increments
(Increments to existing SAGD Satellite)

	SAGD	SAGDOX

Pipelines
Total Liquids (bbl/bbl bit)	9.0	3.0
Total Gases (MSCF/bbl bit)	1.48	2.46
CO₂Emissions
W/O Capture (MSCF/bbl)	1.48	2.46
W Capture (MSCF/bbl)	1.48	0
Water Used
(bbl/bbl bit)	0.34	0
Electricity Used (ASU)
(kWh/bbl bit)	0	27.5

Where:
1. See Table 7 for details
2. Zero electricity assumed for SAGD

TABLE 10

Capex Items

At Satellite Site

At Central Site

	SAGD	SAGDOX	SAGD	SAGDOX

Steam Boilers (OTSG)	Yes	Yes (−)	No	No
ASU Oxygen	No	No	No	Yes
Vent Gas Treating	No	Yes (?)	No	No
Water Treatment	No	No	Yes	Yes (−)
Oil/Water Separation	No	No	Yes	Yes (−)
Water Disposal	No	No	Yes	Yes (−)
Pipeline Corridor	Yes	Yes (−)	—	—
New Wells	Yes	Yes (+?)	—	—

Where:
1. SAGDOX pipelines - one extra line (oxygen), less liquids and more gas
2. SAGDOX boilers - much less than SAGD
3. SAGDOX gas treating - may not need, may not be substantial
4. Water treating, separation and disposal - less for SAGDOX
5. New wells - more for SAGDOX with separate O₂injectors and produced gas removal
6. Yes means there is expenditure; no means there is no expenditure; Yes (−) means, while there is expenditure, it is less than SAGD; Yes (+) means more expenditure than SAGD; and Yes (?) means there is more expenditure, but the exact amount is uncertain.

TABLE 11

New 10KBD Satellite: Pipeline Size Comparisons (D inches) (No Diluent)
% Oxygen in Steam and O₂Mixes (v/v)

	0	5	9	20	35	50

Liquids
Treated Water	8.96	7.24	6.34	4.76	3.52	2.67
Bit + Water	10.2	8.73	8.00	6.81	6.02	5.56
Subtotal D	19.16	15.97	14.34	11.57	9.54	8.23
Gases
Nat Gas Fuel	4.30	3.46	3.04	2.29	1.69	1.27
Oxygen	0	3.28	3.92	4.69	5.10	5.29
Subtotal D	4.30	6.74	6.96	6.98	6.9	6.56
Total D	23.46	22.71	21.30	18.55	16.33	14.79
% of SAGD	100	96.8	90.8	79.1	69.6	63.0

Where:
1. D = pipeline dia (inches)
2. Assumes liquid pipelines at 5 ft./sec
3. Gas pipelines at 500 psia and at 50 ft./sec
4. For liquids D = (Q/420)^1/2; Q = bbls/day
5. For gases D = (Z/0.801)^1/2; Z = MMSCFD gas
6. Volumes based on Table 5

Claims

1. A SAGDOX satellite system for recovering hydrocarbons, the system comprising a central SAGDOX site, at least one SAGDOX satellite site, and a pipeline corridor for communication between the central SAGDOX site and the SAGDOX satellite site, wherein the satellite system is designed to recover hydrocarbons using a SAGDOX process at the satellite site and transfer recovered hydrocarbons to the central site.

2. The SAGDOX satellite system of claim 1 wherein said at least one SAGDOX satellite site is distant said central SAGDOX site from 9 km to 160 km.

3. The SAGDOX satellite system of claim 2 wherein said distance is from 10 km to 100 km.

4. The SAGDOX satellite system of claim 1 wherein the central site comprises:

(a) an oil/water separation unit,

(b) an oil collection unit,

(c) a water treatment unit, and

(d) an oxygen generation unit,

the satellite site comprises:

(a) a boiler for steam generation,

(b) at least one steam injection well,

(c) at least one oxygen injection well, and

(d) a bitumen recovery well,

and the pipeline corridor comprises:

(a) an oxygen supply pipe,

(b) a treated water supply pipe,

(c) a natural gas supply pipe, and

(d) a bitumen and water recovery pipe.

5. The SAGDOX satellite system of claim 4 wherein the recovered oil/water emulsion is further combined with a diluent at the satellite site, and the pipeline corridor further comprises a pipe for delivering said diluent to the satellite site.

6. The SAGDOX satellite system of claim 4 wherein the satellite site further comprises a vent gas treating unit for sequestering CO₂and/or other produced gases.

7. The SAGDOX satellite system of claim 1 wherein each central unit has more than one satellite unit attached to it with one or more pipeline corridors.

8. The SAGDOX satellite system of claim 7 wherein at the satellite site the steam and oxygen mixture is injected into an underground chamber in one of the following ways: the mixture is a) simultaneously injected into the same well, b) simultaneously injected into several wells or c) steam and oxygen are separately injected into separated wells for steam and oxygen and the mixture take place in the underground chamber.

9. The SAGDOX satellite system of claim 8 wherein the concentration of oxygen in the steam and oxygen mixture of the SAGDOX is from 5% to 50% (v/v).

10. The SAGDOX satellite system of claim 8 wherein the concentration of oxygen in the steam and oxygen mixture of the SAGDOX is from 10% to 40% (v/v).

11. The SAGDOX satellite of claim 8 wherein the concentration of oxygen in the steam and oxygen mixture is about 35% (v/v).

12. A process of upgrading an existing SAGD facility by transforming it into an SAGDOX satellite system, the process comprises:

installing an oxygen generation unit at the central SAGD facility,

providing at least one remotely located SAGDOX satellite site, and

providing at least one pipeline corridor between the central facility to the at least one satellite site, said corridor having additional pipes for oxygen supply and pipes for produced water and natural gas supply, such that while the oxygen, water and natural gas are supplied to the satellite site; oxygen with generated steam is injected into an underground formation; and recovered from the underground formation, bitumen with water emulsion is pumped back to the central site, then the bitumen is separated from the water, and treated water is sent back to the satellite site for steam generation.

13. A process for recovering bitumen from a satellite bitumen production site and delivering bitumen to a central facility, whereby:

(a) locating the satellite site more than 10 km from the central facility,

(b) linking the satellite site and the central facility via a pipeline corridor, this corridor containing pipes to provide treated water, suitable for boiler use, from the central site; providing oxygen gas from the central facility to the satellite, for SAGDOX; providing produced fluids (bitumen and water) to the central facility from the satellite site, and

(c) recovering bitumen at the satellite site via the SAGDOX process.

14. The process according to claim 13, wherein the produced fluids (bitumen and water) are conveyed from the satellite site to the central facility in a push-water system.

15. The process according to claim 13, wherein the produced fluids (bitumen and water) are conveyed as a stabilized emulsion, with a chemical stabilizer added at the satellite site.

16. The process according to claim 13 whereby a diluent is also delivered to the satellite site and blended with produced fluids (water and bitumen) for transport back to the central facility.

17. The process according to claim 13 wherein natural gas or fuel gas is also provided to the satellite site, from the central facility by the pipeline corridor, as a boiler fuel.

18. The process according to claim 17 wherein electricity is also transported from the central facility to/from the satellite site.

19. The process according to claim 18 wherein a produced gas (CO₂) pipeline is added to convey SAGDOX vent gas from the satellite site to the central facility.

20. A process according to claim 13 wherein an existing SAGD satellite is converted to SAGDOX, utilizing the existing steam capacity at the site.

21. A process according to claim 13 wherein produced water is separated at the satellite site, wherein the diluted bitumen, is conveyed back to the central facility generally free from excess water.