CN105121778A - Use of steam assisted gravity drainage with oxygen ("SAGDOX") in the recovery of bitumen in thin pay zones - Google Patents

Abstract

The invention discloses use of steam assisted gravity drainage with oxygen ("SAGDOX") in the recovery of bitumen in thin pay zones. A SAGDOX process is used to recover liquid hydrocarbons from at least one thin pay zone in a hydrocarbon bitumen reservoir, via a substantially horizontal production well, where the hydrocarbon bitumen reservoir has a top and a bottom. The process includes: i) Injecting steam into the hydrocarbon bitumen reservoir above the substantially horizontal production well; ii) Injecting oxygen into the hydrocarbon bitumen reservoir above the substantially horizontal production well; iii) Recovering liquid hydrocarbon via gravity drainage into the substantially horizontal production well.

Description

The SAGD (" SAGDOX ") of oxygen is used to gather in thin oil-producing area the purposes of pitch

Background technology

SAGD (" SAGD ") uses in saturated vapour Injection Level well, business-like hot intensified oil reduction (" EOR ") technique, wherein use latent heat to carry out heated asphalt and reduce the viscosity of pitch, make it be let out in parallel, the paired parallel horizontal wells of below by gravity, complete near reservoir substrate.

Since this technique started in early days in the 1980's, SAGD has become in the Pitch deposits in order to economize (Alberta) from Alberta the main in-situ process (Butler of pitch of gathering, R., " ThermalRecoveryofOil & Biumen ", Prentice-Hall, 1991).The SAGD bituminous production economized at Alberta is at present about 300,000 barrels/day, and installed capacity is about 475,000 barrels/day (OilsandsReview, 2010).SAGD is hot EOR technique advanced in the world now.

Fig. 1 (prior art) demonstrates traditional SAGD geometry, it is used in paired, parallel, horizontal well 2,4 that same vertical plane is holed, upper well 2 and the spacing of going into the well between 4 are 5 meters, each well is about 800 meters, and 1 to 2 meters above the substrate of (level) reservoir of going into the well.Cyclic steam 6 in two wells starts SAGD process.After setting up UNICOM, well 2 is used to inject steam 6 and go into the well 4 extraction hot water and heated bitumen 8.Liquid exploitation is realized by natural elevate a turnable ladder, gaslift or submersible pump.

After being transformed into normal SAGD operation, vaporium is formed around Injection Well 2 and recovery well 4, and wherein void space is occupied by steam 6.Steam, in the border condensation of room, discharges latent heat (condensation heat) and heated asphalt, connate water and reservoir matrix.Let out in lower recovery well 4 by gravity by the pitch that heats and water.Along with pitch is let out in lower recovery well 4 by gravity, vaporium upward and outward increases.

It is how ripe that Fig. 2 (prior art) demonstrates SAGD.The vaporium 10 at initial stage makes pitch from side, precipitous room and room top layer draining.When room increases touching reservoir top, top layer draining stops, and asphalt production rate peak value and angle of sides proceed along with side direction increases and decline.Heat waste increases with top layer contact and steam chamber surface is amassed increase and increased (steam increases with the ratio (" SOR ") of oil).Draining speed reduces with side wall angle and slows down.Finally, limit is economically reached and the draining angle of end of lifetime little (10-20 °), as shown in Figure 2.

The fluid of extraction, close to saturation temperature, therefore only has the technique that the latent heat of steam contributes in reservoir.But some sensible heats can be caught from surface heat exchanger (part larger higher temperature), the useful rule of thumb of steam net heat contribution is made to be 1000BTU/ pound.For pressure (" P ") and temperature (" the T ") scope of most of SAGD project, shown in as good in Fig. 3 (prior art) institute.

The operating characteristics of SAGD can be characterized by the measurement of following parameter: the saturated vapor pressure (" P ") in vaporium and temperature (" T "), as shown in the best in Fig. 4 (prior art); Asphalt production rate; SOR, usually at well head; Cross cold---the temperature difference between saturated vapour and extraction fluid; And WRR---recovered water and the ratio (also referred to as water circulation ratio) injecting steam.

In SAGD activities, SAGD operator needs to carry out twice selection---cross the operating pressure in cold target temperature difference and reservoir.It is in order to ensure not having live steam to penetrate into recovery well that the typical case of about 10 to 30 DEG C crosses cold target.Operation pressure and temperature correlation join (Fig. 4) and mainly relate to asphalt production rate and process efficiency.Asphalt viscosity is the majorant of temperature, as shown in Fig. 5 (prior art) the best.SAGD productivity ratio is proportional to the square root of reciprocal viscosity, see Fig. 6 (prior art) (Butler (1991)).But on the contrary, if P (and T) increases, then the latent heat content of steam declines rapidly (Fig. 3) and more energy is used to heating Rock Matrix and is lost to covering layer or other non-producing region.The pressure increased adds asphalt production rate, but harm process efficiency (improve SOR).Because economic benefit can be dominated by asphalt production rate, thus SAGD operator usually select using operating pressure higher than natural, hydrostatic reservoir pressure as target.

Although becoming main hot EOR technique, SAGD has some restriction and impaired parts.Good SAGD project comprises:

Horizontal well is completed effectively to collect and to produce hot draining fluid near bottom oil-producing area.

High-quality steam is injected in sand face.

It is effectively with easily that technique starts.

Vaporium grows steadily and is received.

Reservoir matrix quality good (Φ >.2, S _i0>.6, k _v>2D).

Clean oil-producing formation is enough (>15 rice).

Suitable design and control are to prevent steam from penetrating, prevent Injection Well overflow, stimulate vaporium to rise to mining area and suppress water to flow into vaporium simultaneously.

Obvious reservoir is not had to roll over block material (such as poor district) or barrier (such as shale).

If these features do not realize or stand other restrictions, so SAGD can be impaired, as follows:

(1) preferred main exploitation mechanism is gravity drainage and lower recovery well is level.If reservoir high inclination, then horizon mining well can be detained (strand) significant resource.In other words, the pitch below horizontal well can not be gathered.

(2) SAGD steam-purge zone has the remarkable residual bitumen content of not gathering, particularly for compared with the pitch of heavy and low-pressure steam, as shown in Fig. 7 (prior art) the best.Such as when 20% residual bitumen (hole saturation ratio) and 70% initial saturation, recovery ratio only has 71%, does not comprise below recovery well or delay pitch in the tapered region of gathering between well pattern.

(3) in order to " accommodation " SAGD vaporium, the oil in reservoir must be relatively-stationary.SAGD can not work to having under reservoir conditions certain ambulant heavy (or lightweight) oil.Pitch is selected objective target.

(4) saturated vapour can not evaporate connate water.According to definition, the thermal energy in saturated vapour does not have sufficiently high quality (temperature) with evaporation water.The connate water that field experience also demonstrates heating does not have enough mobility with extraction in SAGD.Recovered water is similar with SOR with the ratio (" WOR ") of oil.This makes SAGD be difficult to break or utilize poor area resource.

(5) existence in active pool---poor district of the top layer water in oil-producing area, bottom water or distribution---can cause SAGD operating difficulties or finally can cause project failure (NexenInc., " SecondQuarterResults ", on August 4th, 2011) (Vanderklippe, N., " LongLakeProjectHitsStickyPatch ", CTV, 2011).Analog study is reached a conclusion, the standoff distance increasing recovery well can optimize the performance of the SAGD with active bottom water, comprise good Stress control to minimize water influx (Akram, F., " ReservoirSimulationOptimizesSAGD; AmericanOilandGasReporter, in September, 2011).

(6) (always) pressure target can not be improved to improve SAGD productivity ratio and SAGD economy.If reservoir is " leakage ", so along with raising pressure exceedes natural hydrostatic pressure, SAGD technique can lose water or steam to the region outside SAGD vaporium.If loss of liquid, then WRR reduces and technological requirement significant water compensation volume.If steam also loses, then process efficiency declines and SOR rising.Finally, if pressure is too high, and if if reservoir shallow high pressure retention time is long, then can there is steam, sand and penetration by water surface (Roche, P., " BeyondSteam ", NewTech.Mag., in September, 2011).

(7) steam cost is considerable.If the steam cost comprising Capital expenditure and some profits exceedes effectiveness border, then the cost of the high quality steam in sand face is about 10 to 15 dollars/MMBTU.High steam cost can reflect resource quality limit and ultimate recovery.

(8) use of water is remarkable.Suppose SOR=3, the yield of WRR=1 and produced water treatment (that is, recycling) is 90%, and typical SAGD water is 0.3 barrel of compensation water/bucket extraction pitch.

(9) SAGD process efficiency " bad " and CO ₂discharge value remarkable.If SAGD efficiency is defined as [(pitch energy)-(surface energy of use)]/(pitch energy) and pitch energy=6MMBTU/ bucket; Energy=1MMBTU/ bucket the pitch (SOR ~ 3) used in sand face; Steam produces in gas-burning boiler with the efficiency of 85%; Be assigned to well head and be delivered to each heat waste of own 10% in sand face from well head; Available steam energy is 1000BTU/ pound (Fig. 3) and boiler oil is the methane of 1000BTU/SCF; So SAGD process efficiency=75.5% and CO ₂discharge value=0.077 ton of/barrel of pitch.

(10) due to heat waste, the cost of the pressure loss and isolation distributing steam pipeline, steam distribution distance is restricted to about 10 to 15 kilometers of (6-9 mile) (Finan, A., " IntegrationofNuclearPower ... " MIT paper, in June, 2007 (EnergyAlbertaCorp., " NuclearEnergy ... " CanadianHeavyOilAssociationpres., on November 2nd, 2006).

(11) last, there is the long or well diameter of restriction well and " natural " waterpower limit of the pressure target of SAGD operation can be had precedence over.What Fig. 8 demonstrates and can occur to occur with what.In SAGD, form vapor/liquid interface 12.For the good SAGD operation with cold control, interface is between Injection Well 2 and recovery well 4.Pressure drop because fluid flows in the recovery well 4 that causes, interface tilts.In steam gas room pressure reduction very little/there is no pressure reduction.If liquid extraction speed too high (if or recovery well 4 too little), so interface can be tilt, and the toe of steam injection well 14 is submerged and/or the penetrating (Fig. 8) with being exposed to steam of recovery well 16.(for 5 meters of spacing, be about 8psi (50kPa)) when the pressure drop in recovery well 4 exceedes the hydrostatic head between steam injection well 2 and liquid recovery well 4, this restriction can occur.

Thin oil-producing area reservoir (thin oil-producing area)

For object herein, " pitch " is defined as the oil of high density (API<10) and high original position viscosity (>100,000cP), makes elementary exploitation be zero or very little.Pitch is the hydrocarbon that do not flow under reservoir conditions.

Maximum deposition is found in the Athabasca district of Alberta province---and McMurray deposits (table 1).Fig. 9,10,11 and 12 characterizes this deposition.Fig. 9 demonstrates the degree of depth of McMurray stratum top layer---i.e. tectal thickness.Figure 10 demonstrates thickness---porous and the non-porous both areas that total McMurray deposits.Figure 11 demonstrates porosity interval---and the clean thickness of the porous part of described deposition, has the porosity boundary (cutoff) (this part contains pitch, water and occupies the gas of pore volume) of 10%.Figure 12 demonstrates the clean oil-producing area thickness of pitch---the part of porosity interval (porosityinterval).Difference between porosity interval and pitch oil-producing area is the affected area showing EOR technique---gas, top layer water, bottom water or poor district.These regions can be inner in the clean oil-producing area of pitch or adjacent (top/bottom).

According to estimates, 4100 hundred million barrels of asphaltene deposition are being less than (table 1) in 10 meters of thick thin oil-producing areas (Henrick, T.etal, " OilSandsResearchandDevelopment; AlbertaEnergyResearchInstitute, in March, 2006).Overwhelming majority's (3,800 hundred million barrels, 93%) of these small propertys oil reservoir (district) is in Athabasca district.If small property oil regional boundary limit is set in 15 meters instead of 10 meters, so thin oil-producing area pitch resource is than carbonate pitch resource more (table 1).In any case, the thin oil-producing area pitch that Alberta is economized is the hydrocarbon resource of world-class scale.

Figure 12 demonstrates the west side that thin oil-producing area concentrates on McMurray deposition.Fig. 9 demonstrates the covering layer depth bounds that these depositions can have the about 100-300 rice depending on position.Hydrostatic pressure scope is about 160-500psia, the degree of depth that the Hydrostatic pressure gradient of use is 0.5psia/ foot.

Figure 13 demonstrates the API gravity of McMurray stratum medium pitch deposition.This asphalt density is changed to 10API from 7, and compared with the pitch (higher API) of lightweight in the west and south of this deposition.

Based on Fig. 9,10,11,12 and 13, the thin oil-producing area pitch resource that Alberta is economized can be characterized by by we:

Shallow to middle deep (100-300 rice covering layer)

Low to middle pressure (160-500psia hydrostatic head)

Be positioned at the west side of Athabasca deposition

EOR is high to moderate impaired (difference based between clean porosity interval and clean oil-producing area pitch)

Large opportunity (hundred million barrels of protobitumens of >4000 in position (" OBIP "))

Known technology is not had to gather economically thin oil-producing area pitch (Heinrick (2006))

Considerably less (if any) research and development focus on this opportunity (Heinrick (2006))

API density in 7 to 10 scopes

Thin region, is preferably less than about 25 meters, is more preferably less than about 15 meters

SAGD minimum clean oil-producing area limit has been estimated as 10-15 rice (Heindrick (2006)).Determine that the factor of this limit is as follows:

(1) SAGD geometry

Be difficult to that SAGD well is constructed be adapted to be less than in the clean oil-producing area of about 10 meters.Being spaced apart about 5 meters (Fig. 1) between Injection Well 2 and production of water horizontal well 4.This recovery well is positioned near reservoir bottom, but requires the standoff distance of 1 to 2 meter.Similarly, the standoff distance of distance reservoir top layer number meter is needed compared with the horizontal steam Injection Well 2 of top.In SAGD also requires that horizontal well is in (or close) horizontal plane.If reservoir tilts, what for be adapted to small property oil reservoir to the more difficult SAGD of making geometry.

(2) asphalt production rate

Asphalt production rate for prevailing economic factor SAGD project.If small property oil area resource is shallow, so productivity ratio can directly be subject to oil-producing area thinness or pressure influence.

It is good predict to productivity ratio sensitivity that Gravdrain equation (Butler (1991), Fig. 6) has demonstrated.Productivity ratio is proportional to the square root of clean oil-producing area.This equation can be used for prediction, and due to clean oil-producing area, to reduce the productivity ratio caused impaired.Such as, if by the desirable SAGD project of 50 meters of clean oil-producing areas with comparing, then the productivity ratio decline of following less clean oil-producing area (that is, thin oil-producing area) is contemplated to:

25 meters of clean oil-producing areas---29% loss in productivity

15 meters of clean oil-producing areas---45% loss in productivity

10 meters of clean oil-producing areas---55% loss in productivity

5 meters of clean oil-producing areas---68% loss in productivity

These estimate not consider, due in homogenieity, well pattern boundary effect, to hold loss, or heat waste in pressure effect and the loss in productivity that causes.

The impact of the degree of depth can be more violent.Fig. 9 and 12 demonstrates some small property oil area resource expections and is in the degree of depth lower than most of thick oil-producing areas resource.If people are near earth's surface, then under over pressure, operate SAGD risk too high.People are forced in operation near primary/hydrostatic pressure.Pressure reduces and can produce dramatic impact to asphalt production rate.

By using 1) saturated vapour character (Fig. 4); 2) asphalt viscosity curve (Fig. 5); And 3) Gravdrain equation (Fig. 6) estimates the change of productivity ratio with viscosity B coefficent, can by supposing following situation to estimate the SAGD loss in productivity of more shallow reservoir: 1) under hydrostatic pressure, carry out SAGD operation; 2) reservoir thickness is unchanged; With 3) at the base case of 300 meters of degree of depth.The SAGD loss in productivity of more shallow reservoir is estimated as follows:

The 200 meters of degree of depth-15% loss in productivity

The 100 meters of degree of depth-45% loss in productivity

The 50 meters of degree of depth-66% loss in productivity

The impact that thickness reduces and the degree of depth reduces is independently and is cumulative.So, if people using operating 50 meters of clean oil-producing areas of 300 meters of covering layer degree of depth as benchmark under hydrostatic pressure, so reduce there being the productivity ratio of 85% in 10 meters of clean oil-producing areas of 50 meters of degree of depth.This can be destructive to the economy of SAGD.

(3) pitch is gathered

In the life-span anagenic phase of SAGD project, under economic limit, drain path that the cross section of gravity drainage (GD) vaporium (in homogeneous reservoir) takes linear shape, that tilt and fixing draining angle (Fig. 2).If suppose steam-purge zone and do not purge the sharply sudden change between region, and if know the draining angle of final period in life-span, then can calculate reserves of can gathering.Figure 14 demonstrates to base case SAGD project that (1 meter of bottom well is biased, Φ=.35, S for 25 meters of clean oil-producing areas, 100 meters of well spacing _io=.8, S _ro=.15, θ=15 °) calculating carried out.The recovery ratio of this project is 56%OBIP---the typical expected of SAGD.

Suppose that performance is identical, Figure 15,16,17 demonstrates some calculating of 10 meters of thin oil-producing area reservoirs.Well spacing is 100 meters (identical with our base case), is 67.2 meters and makes draining interface intersection in the corner of well pattern of gathering, and be 29.8 meters make the rate of recovery and base case similar.

Result can be summarized as follows:

Therefore, if we wish that spacing is identical with our base case, then pitch recovery ratio (0.213) is unacceptable.If we keep identical recovery ratio (~ 0.56), then well spacing must be reduced to 29.8 meters from 100 meters by us.Well density is increased above 3 times by us.This will appreciably increase the capital cost of per unit extraction pitch.

(4) limit economically

In order to the economic problems of SAGD in small property oil asphalt reservoir and misgivings are described, we have constructed the naive model of life-span final SAGD, and as shown in figure 18, it has following main hypothesis:

Lower recovery well is 2 meters from the standoff distance of reservoir bottom;

Aspect ratio (well pattern width: well pattern thickness) is 4.This causes the draining angle of final period in life-span to be 10-13 °;

The base case of 25 meters of clean oil-producing areas.Speed of gathering keeps equal to 10 years.(S _io＝0.80，S _ro＝0.15，Φ＝0.35)；

According to Fig. 6, the efficiency average of thin reservoir reduces (be not clean oil-producing area shallow reason);

Suppose that only return (netback) of pitch (to well head) is 10 dollars/barrel, we calculate and add up only to return under the discount rate of 0,10 and 20%.

For the SAGD wells of 1000 meters long to geometry, we are calculated as follows:

Pay thickness (rice)

This simple model does not reduce (shallow resource) because of pressure, or is greater than our heat waste of base case pro rata, or start delay (supposing OnNow) and be unfavorable for the productivity ratio of small property oil reservoir.So the productivity ratio of thin oil-producing area is likely optimistic.

According to our model, we observe following:

The draining angle (10-13 °) of final period in life-span is real for SAGD.Recovery ratio is reasonably (44 to 56%).

Use SAGD in order to the resource of reasonable amount of gathering, thin oil-producing area reservoir well spacing obviously must reduce (such as, 40 meters of spacing for 10 meters of clean oil-producing areas).

If people only can realize productivity ratio impaired (that is, other factors is constant) by reducing pay thickness, so small property oil area resource exhausted very fast (such as, for 10 meters of clean oil-producing areas 2.2 years)

This model hypothesis instant (on average) productivity ratio in the 1st year.Postpone the economy more seriously damaging thin oil-producing area due to short running length.

If people suppose that keep in repair, that SAGD, 1000 meters of wells are right cost is 5-10 1,000,000 dollars, so people see the oil-producing area boundary of about 15 meters.

If being only returned as of pitch double (20 dollars/barrel), so oil-producing area boundary can be less than 15 meters for SAGD.

And if if people maintain the 5 meters of spacing also keeping between steam injection well and recovery well from the standoff distance of reservoir bottom 2 meters, so SAGD cannot be applied to the reservoir that pay thickness is less than 7 meters.

Figure 19 demonstrates in the life-span of SAGD final, the pitch of not gathering the how reservoir portion below wedge area, recovery well plane and distributing between the residual bitumen in steam-purging region.Along with clean oil-producing area is reduced, the pitch below recovery well plane becomes most important resource of not gathering, and this is different from wherein wedge area pitch and accounts for leading thick SAGD.

(5) to gather inhomogeneity

Up to now, discuss SAGD and be applied to misgivings in the thin reservoir of homogeneous.But, do not have reservoir to be real homogeneous.Shale, mudstone, poor district, top/bottom water and top layer gas all can cause inhomogeneity.

SAGD is gentle technique.It also can be known as meticulous technique.Exploitation is ordered about by the gravity head in reservoir.The hydrostatic gravity head of 30 meters of oil-producing area reservoirs is very low---only about 50psia (maximum value).Gravity gradient is only about 0.5psi/ft or 1.6psi/m.SAGD is also two-dimentional technique.Obvious reservoir stream is not had in horizontal well direction.Water in reservoir or heterogeneous body can not be evaporated by SAGD.For this reason, in homogeneous reservoir, Hele-Shaw two-dimensional physical model can predict actual SAGD performance well.In addition, SAGD is temperature limited in saturated steam conditions.

Due to these reasons above-mentioned, SAGD is difficult to overcome any reservoir inhomogeneity that can destroy flowing mode.

(6) harvest efficiency

The efficiency measurement being usually used in SAGD is SOR.SOR and efficiency negative correlation---low SOR ~ high thermal efficiency.The energy of SOR required for the energy heated required for reservoir matrix, heating reservoir fluid (pitch and water) is determined with the heat waste (being transported to both the direct losses in the process of Injection Well and in the reservoir at covering layer/underlying bed interface downwards) arriving covering layer and underlying bed.Under comparatively low vapor pressure, it is because the loss adding heat reservori and compensate covering layer/underlying bed needs less heat that SOR declines.Thin oil-producing area deposition will be increased to tectal loss, because vapor interface will touch top layer sooner than thick oil-producing area resource.Other all are all equal, are lost to tectal energy and top-level list area is proportional.Top-level list area/unit OBIP and (1/h) are proportional, the wherein clean oil-producing formation of h=.Utilize this relation, we it is expected to the heat waste/unit OBIP of 10 meters of oil-producing area reservoirs than large 2.5 times of 25 meters of produce oil reservoirs.So except the misgivings expressed (productivity ratio and recovery ratio), thin oil-producing area pitch SAGD will have the SOR (the lower thermal efficiency) higher than thick oil-producing area pitch SAGD.

(7) sum up

In a word, the SAGD in the bitumen reservoir of thin oil-producing area has following defect:

Be difficult to make traditional SAGD geometry (Fig. 1) to meet well in reservoir.

Compared with thicker oil-producing area reservoir, small property oil asphalt reservoir will have significant asphalt production rate and decline.

If thin oil-producing area reservoir is shallow and operates under SAGD is forced in close to natural reservoir pressure pressure, then asphalt production rate reduces further.

Unless minimizing spacing, increase drilling cost, it is poorer than thicker oil-producing area pitch resource that pitch is gathered.

Income from thicker oil-producing area resource is starkly lower than by the thin oil-producing area pitch income produced of gathering.Even if when productivity ratio due to reduce gravity head and reduce time, with thicker oil-producing area resource more than 10 years compared with, small property oil the paneling only sustainable several years.

SAGD is to the impaired sensitivity of reservoir (shale, poor district ... Deng).If these are impaired more general in the reservoir of thin oil-producing area pro rata, then SAGD will go wrong as discussed herein.

Heat waste can reduce process efficiency.The oil-producing area resource that thin oil-producing area reservoir is thicker has larger heat waste and arrives covering layer or underlying bed.

Although SAGD has these defects, it is still considered to be used in thin oil-producing area pitch and gathers.At the McMullen that Alberta is economized, Husky has proposed the thin oil-producing area SAGD project of 3,500 ten thousand dollars, 10 to 16.5 meters of clean oil-producing area (Roche in Wabaskaw stratum, P., " NoAnalogue ", NewTech.Mag, on April 1st, 2009).Be 15 meters for generally accepted oil-producing area thickness limit SAGD, but this can be pushed into downwards 10 meters.

Based on above-mentioned analysis, the SAGD for small property oil area resource improve or the expectation attribute of new pitch EOR technique as follows:

Reduce the well cost that every barrel is reclaimed pitch.This can be constructed by new well, reduce well size, lengthening (level) well or use recyclable and reusable well group part to realize.

Reduce unit operation expense.This can by injecting than the energy of steam cheapness or by using the technique needing less energy to exploit pitch to realize.

Improve asphalt production rate.This can by the hotter technique of operating ratio SAGD, introduce new mechanism of gathering or increase that well is long to be realized.

Increase the productivity ratio of impaired reservoir.This can by three-dimensional, more easily to break barrier (such as, evaporation water ...) technique or the hotter technique of operating ratio SAGD realize.

Improve ultimate recovery.These can by some residual bitumens of gathering from steam-purge zone, or the technique of the more heavy wool of gathering from the tapered region of gathering between well pattern realizes.

Improve the value of extraction pitch.This can be realized by the upgrading of part original position.

Improve environmental-protecting performance.This can by the use of minimizing (compensation) water, raising process efficiency, minimizing CO ₂discharge value or minimizing surface splats realize.

Except SAGD, advise that following technique is applicable to thin oil-producing area pitch and gathers:

I () expanded solvent SAGD (ESSAGD) has been considered to the technique (Gates for thin oil-producing area, I. " SolventAidedSAGDinthinoilsandreservoirss, JournalofPetroleumScienceandEngineering2010 April 24).This idea is only that the independent steam of steam and ratio of solvent is more effective.Dissolution with solvents in pitch can reduce viscosity and provide the mechanism of gathering being different from independent steam.But this technique has following defect:

Under identical P, operating temperature is lower than SAGD, because steam is diluted by solvent gas.Heat waste can be reduced, but only due to asphalt heating, productivity ratio also reduces to some extent than SAGD.

The geometry of this technique is similar to SAGD.This process is two-dimentional technique, does not have reservoir to flow at longitudinal direction.Well cost (capital cost) is similar to SAGD.

Solvent (butane, condensing agent, BTX ...) very expensive (more valuable than pitch).If there is any neat solvent to be lost to reservoir (leak, retain), then operating cost can be equal or higher with SAGD.

Solvent loss degree is until project terminates to be all unknown.

In the pitch of thin oil-producing area, do not carry out ESSAGD on-the-spot test.

(ii) also advised by the steam injection well on biased lateral, or multiple side direction recovery well is added SAGD geometry, SAGD geometry (the Tavallali in the reservoir of thin oil-producing area can be changed, " AssessmentofSAGD... " SPE153128, in March, 2012).But this technique has following defect:

Capital cost is similar to SAGD.Well number and well are grown constant.

This technique focuses on mink cell focus and non-bituminous.

This technology remains the misgivings of other SAGD---the well spacing of bad productivity ratio, bad energy efficiency and bad recovery ratio or increase.

(iii) also the built view vertical-horizontal Injection Well of a series of overlap replaces parallel SAGD steam injection well (Stalder, " CrossSAGD (XSAGD) ... " SPEReservoirEvaluation & Engineering, 2007).This technique is called as intersection SAGD or XSAGD.This results in the grid crossing with the grid of parallel, horizontal recovery well (spacing is similar to SAGD (5 meters)) of parallel, horizontal steam injection well.The defect of XSAGD is similar with (ii) above.

(iv) also advise the solvent not using steam, use VAPEX technique (NewTechMag., " VAPEXshowspromisebutstuckinlab ", 2005).But this neat solvent technique has following defect:

This technique confirms in testing at the scene that being difficult to (slowly) starts.

Productivity ratio SAGD is much lower.

Solvent very expensive (more expensive than pitch), therefore, even a small amount of loss, operating cost is also misgivings.

This technique is two-dimentional, in reservoir, do not have longitudinal stream.

Emphasis has transferred to mink cell focus (have certain initial injectability) and non-bituminous.

Solvent loss (to reservoir) is main economy misgivings.Unfortunately, when expecting that solvent reclaimed in emptying (blow-down) stage, until project terminates to determine net loss.

V () individual well SAGD (" SWSAGD ") is another replacement scheme (Elliot for thin oil-producing area pitch and mink cell focus application, K.etal, " ComputerSimulationofSWSAGD ", U.S.DepartmentofEnergy, 14994-18, in July, 1999) (ELANEnergy, " AnnouncesSixMonthResults ", in August, 1996) (ImprovedRecoveryWeek, " ThermalSystemupsheavyoil ... " December 4 nineteen ninety-five).This idea is injected by steam 6 to be merged into single horizontal well with pitch+water 8 exploitation, uses (Figure 20) (or not using (Figure 21)) hot packer 18, to inject and pitch+water 8 is exploited to isolate steam 6.

Primary objective is the mink cell focus deposition (Ashok that W.Saskatchewan and E. Alberta is economized, K.etal, " AMechanisticStudyofSWSAGD ", SocietyofPetroleumEngineers, 59333-MS, 2000) (ELANEnergy, " AnnouncesNineMonthEarnings; in November, 1996) (Luft; H.B.etal, " ThermalPerformanceofInsulatedConcentricCoiledTubing (ICCT) forContinuous ..., " SPE; 37534-MS, 1997).Nineteen ninety-five, first SWSAGD well CactusLake, Saskatchewan boring (HOSC (HeavyOilSci.Cent.) " CompletionsandWorkovers ", www.lloydminsterheavyoil.com, 2012).Elan has carried out on-the-spot test several times (Elliot (1999), (Saltuklaroglu, M.etal with other people in generation nineteen ninety, " Mobil'sSAGDExperienceatCeltic; Saskatchewan " SPE, 99-25, in June, 1999).

Compared with SAGD, SWSAGD has the longitudinal stream determined, therefore it more easily can process barrier and have the well cost of the minimizing determined.But it is also obvious for below worrying:

The concentric steamline of centralization (line) 6 contacts (Figure 20,21) with extraction liquid (water+pitch 8).This extraction liquid has high heat capacity and (that is, SAGD) this fluid will be in the temperature (that is, cross cold control) lower than saturated vapour usually.For that do not isolate, concentric carbon steel tube, can be considerable from steam injection well to the heat waste of extraction fluid.Heat waste from steam 6 and extraction liquid 8 is also misgivings, because extraction liquid has high-termal conductivity.This extraction liquid 8 is rapidly heated to saturated-steam temperature and quality of steam obviously reduces before being injected into reservoir.Using Automatic steam trap Trap to control (excessively cold) exploitation rate is also difficult from best angle.A solution uses isolated tube as steam injection pipe.Isolating concentric wind pipe (ICCT) is develop for this purpose, but not yet cause at present and widely use (Luft, H.B.etal, " ThermalPerformanceofInsulatedConcentricCoiledTubing (ICCT) forContinuous " SPE, 37534-MS, 1997) (Falk, K.etal, " ConcentricCoiledTubingforSWSAGD ", WorldOil, in July, 1996).

Startability is another problem.Even for the mink cell focus deposition with certain steam injection ability and certain elementary yield, start and be also difficulty and lasting (Elliot (1999)).Initial exploitation rate disappointing (Elliot (1999)).At least in part, this problem is attributable to 2 factors.Because heat waste is to extraction fluid, the primary steam at sand face place is of poor quality.In addition, steam injection position appears at and exploits identical height (Figure 20).Not the same with SAGD standoff distance departs from recovery well with level allowance and prevents steam from penetrating (Fig. 1).Steam by-pass (by-pass) is a subject under discussion (Ashok, K.etal, " AMechanisticStudyofSWSAGD ", SPE, 59333-MS, 2000).Stagnating (standinflux) problem of inflow is another subject under discussion (Elliot (1999)).Due to these subjects under discussion, built view uses the alternative start-up routine (Elliot (1999)) of cyclic steam, but this is without on-the-spot test.

Even upon actuation, SWSAGD performance is also disappointed (Saltuklaroglu (1999), Elliot (1999)).ElanEnergy is inventor and the major carrier of SWSAGD.Before the end of the year 1999, Elan will have bored 19 SWSAGD wells and will have carried out 7 different pilot scales (pilot).To the end of the year 1999, due to poor performance, five times in seven pilot scales other techniques that lain on the table or transferred to (Elliot (1999)).Optimum for high pressure, low viscosity mink cell focus is certain elementary yield as foam oil and does not have bottom water.This technique focuses on dark small property oil reservoir mink cell focus, and non-bituminous.

In 1997, RangerOil & Gas purchased Elan (BusinessDay, " RangerOil...dealforElanEnergy ", on September 3rd, 1997).In 1999, Ranger was by CanadianNaturalResourcesLimited (CNRL) purchase (CNRL " RangerOilagreestoCNRLoffer " 1999).After 1999, there is no the sign that SWSAGD develops further, particularly relevant with pitch.

The on-the-spot test of SWSAGD can be marked as unsuccessful.

(vi) also suggestion use heating, evaporating solvent technique to obtain some advantages of solvent EOR and hot both EOR.Similar with SAGD, form gas-gravity draining (GD) room containing evaporating solvent gas.Similar with steam, solvent, in cold asphalt interface condensation, discharges its latent heat.Then solvent liquid can be dissolved in pitch to reduce viscosity further.This technique be called as N-Solv (Braswell, J., " NewHeavyOilSolventExtractionPilottoTestExperimentalProce ss " TheJournalofPetroleumTechnologyOnline, on January 9th, 2012).This technique claims that ambient influnence reduces compared with SAGD.Field pilot test expection started (Braswell (2012)) in 2013.

But this technique has following misgivings:

Well structure is similar with SAGD.There is no/seldom capital cost reduction.

The test position proposed is thick pitch oil-producing area, does not focus on small property oil area resource.

Similar with SAGD.Two dimension technique.Longitudinal stream is not had at reservoir.

Be difficult to barrier is broken.

Solvent costliness (more valuable than pitch).Solvent loss is Main Economic misgivings.

When attempting to reclaim input quantity of solvent, can not confirm before technique terminates or estimating solvent loss.

Productivity ratio may be poorer than SAGD.

For VAPEX---a kind of similar technique, fieldtesting results difference (NSolv, " DevelopinganInSituProcess... " NSolvweb website, 2012).

Be difficult to start technique.

(vii) use toe-to-with (toe-to-heel) geometry and (toe-to-with the air Injection) burning process being called as THAI has also been proposed to be used in the oily area resource (Figure 22) of small property.This technique uses horizontal well to collect deep fat 8 and burning gases 22.The peupendicular hole injecting compressed air 20 of completion near the toe of horizontal well.Suppose that high-temperature oxydation (HTO) burning is good, this technique may be more cheap than SAGD.This technique use in the lab physical model develop (Greaves, M.etal, " THAI-NewAirInjectionTechnology ... " SPE99-15, June nineteen ninety-five).

PetrobankEnergyandResourcesLtd., Calgary, the ownership having bought and developed this technology economized by Alberta, and developing a series of field pilot test (" THAI " Wikipedia accesses, 2012)).Pilot scale first played operation since 2006.Recently, due to performance poor lastingly, the reserves consultant of Petrobank reduces the reserves (EnergyInc, " PetrobanksufferssetbackwithTHAI ", on March 8th, 2012) relating to THAI.

One of problem of THAI how to stop air to make this technique short circuit and air walk around reservoir (Figure 22) by entering the recovery well of combustion front upstream.In the lab, form coke obstruction (cokeplug) stop bypass by holding before combustion in the recovery well of upstream.If do not form this obstruction in test at the scene, then must use moveable high-temperature packer or sliding sleeve.Any one among these is all difficult task.

Another subject under discussion is, it can be slowly that side direction increases.Do not have/little steam promotion side direction increases and geometry hampers lateral flow component.The burn into sand flow that the other problems pointed out in on-the-spot test comprises in recovery well enters, blocks and explodes.

Other feature/misgivings of THAI comprise as follows:

Air (not being oxygen) is in infusion oxygen-containing gas.

Except for starting, do not inject steam with air (or oxygen) simultaneously.

Imagine wet combustion (water injection) but not yet implement.

Discharge well or other in do not remove separately incoagulable gas, burning gases.These gases are forced through single horizon mining well and remove (Figure 22).This can damage liquid exploitation rate.

The On-site Experience difference (CalgaryHerald, " PetrobankTechnologyearnsZeroGrade ", 2012) of THAI.

THAI focuses on mink cell focus and non-bituminous (OGJ (2012)) at present

(viii) another relevant burning process is overhead burning gravity drainage (CombustionOverheadGravityDrainage) (COGD), also referred to as overhead burning horizontal segmentation (CombustionOverheadSplitHorizontal) (COSH) (Figure 23).Different from THAI, this technique is top-down burning EOR technique.This technique comprises the short path of gathering for pitch, draining is to horizon mining well, independent overhead vertical injection wells and the independent exhaust shaft 22 (level or vertical) removed for burning gases (NewTech.Mag. " ExcelsiorfilespatentforISCProcess ", on September 25th, 2009) (NewTech.Mag. " Excelsiorsearching...COGD... " on November 20th, 2009) of compressed air 24 is used at flank place, well pattern border.The gas of flank is removed system and is facilitated lateral growth---the problem of THAI.In addition, different from THAI, gas and liquid exploitation separate in reservoir, a horizon mining well extraction liquid.

But this technique has following characteristics/misgivings:

The combustion reaction of asphalt interface is complicated, and does not verify through on-the-spot test.

For COGD or COSH, there is no the on-the-spot test of current/imagination.

This process imagine injects air (not being oxygen).

This technique has extra well (extra capital cost) compared with THAI or SAGD.

This technique focuses on mink cell focus and non-bituminous.

(ix) toe-to-be the hot EOR technique (Bagci that another kind is proposed to be used in thin oil-producing area reservoir with steam overflow (THSF) (Figure 24), A.S.etal, " InvestigationofTHSFforheavyoilrecovery " EnergyTechnologyDataExchange, in July, 21025339,2008).But Figure 55 (prior art) also illustrates THSF has shared Injection Well.

Up to the present, THSF focuses on mink cell focus and non-bituminous (Fatemi, S.M.etal, " InjectionWell-ProducerWellCombinationsforToe-to-HeelStea mFlooding (THSF); SPE140703-MS; in May, 2011) (Fatemi; S.M.etal; " PreliminaryConsiderationsontheapplicationofTHSF... "; Chem.Eng.Res. & Design, in November, 2011) (United States Patent (USP) 5626193).With tradition (peupendicular hole) steam overflow facies ratio, (namely THSF has claimed better stability, gravity makes this process stabilizing) and (Turta that better gathers, A.T.etal, " PreliminaryConsiderationsontheapplicationofTHSF... " SPW, 130444-PA, JCPT, in November, 2009).The a small amount of incoagulable gas joining steam shows and improves performance (Turta (2009)).But problem comprises the high cost of steam and lacks on-the-spot test.

But once set up UNICOM between Injection Well 6 and recovery well 8, when not having remarkable steam to penetrate into recovery well, there is pressure reduction hardly and oil is pushed to recovery well.If therefore avoid steam to penetrate, so main mechanism is retinue's toe-to the gravity drainage of-GD vaporium of following advance.This technique is GD but not SF technique now.

X the individual well form (SWTHSF) of () THSF is also determined to have the geometry similar with SWSAGD and technique (US5626193).Emphasis is non-bituminous at thin oil-producing area mink cell focus, and isolated tube is used to steam injection well.The well track proposed, comprising the towing area for steam injection, is level.But problem/misgivings are similar with THSF.

(xi) we will can propose that the replacement scheme being used for thin oil-producing area pitch EOR is summarized as follows at present:

All replacement schemes use mathematical simulation model to study all mostly.

Seldom (or not having) focuses on thin oil-producing area pitch resource.

There are some focus on thin oil-producing area heavy oil resources (THSF, SWTHSF) but pitch EOR is not discussed.

Some replacement schemes comprise physical model test (such as, ESSAGD, VAPEX, N-SOLV, THAI ...), but again, do not focus on thin oil-producing area pitch resource.

Some pitch replacement schemes (such as, ESSAGD, VAPEX, SWSAGD, THAI ...) carry out on-the-spot test, but do not focus on thin oil-producing area pitch.

Some pitch replacement schemes focus on mink cell focus application (and non-bituminous) (such as, THAI, VAPEX, SWSAGD now ...)

These techniques all do not cause any on-the-spot test or the test of laboratory physical model that focus on thin oil-producing area pitch resource.

Some techniques are calculated on-the-spot test (such as, N-SOLV) but again do not focus on thin oil-producing area.

Use and add the hot EOR technique that the SAGD (" SAGDOX ") of oxygen is the improvement of gathering for pitch.This technique can use the geometry (Figure 36) similar with SAGD, but it also has the form (Figure 26,27,28,29,30,31,32,33) with individual wells or the separation point position of removing for oxygen 26 injection and incoagulability exhaust 22.Can think that this technique is the hybrid technique of SAGD and ISC.ISC has demonstrated the technique being seldom applied to pitch and gathering so far.The example of ISC describes (prior art) in Figure 43 and 54.

The object of SAGDOX reduces reservoir energy to inject cost, keeps good efficiency and productivity ratio simultaneously.Oxygen combustion is with about 480BTU/SCF oxygen, and the speed independent of the fuel of burning produces in-situ heat (Figure 34, Butler (1991)).Ignition temperature is independent of pressure and they are higher than saturated-steam temperature (Fig. 4,56).The higher temperature carrying out spontaneous combustion evaporates connate water and some steam that reflux.Steam sends EOR energy from the latent heat discharged by condensation with net value, and the surface heat comprising about 1000BTU/ pound reclaims (Fig. 3).Table 2 illustrates the thermal property of steam+oxygen mixture.Per unit is delivered to the heat of reservoir, oxygen volume is less than 1/10th of steam, and the cost of oxygen (comprising capital cost) is that the half of steam cost is to 1/3rd.

More complicated than SAGD of mechanism of gathering of SAGDOX.Within combustion zone is accommodated in steam-purge zone.Residual bitumen in steam-purge zone by hot combustion gas heating, fractionation and pyrolysis to be provided as the coke of burning natural fuel.The gas compartment formed contains steam burning gases, evaporation connate water and other gas (Figure 35).Large gas compartment can be subdivided into burning-purge zone 100, combustion zone 110, pyrolysis zone 120, heated bitumen bank 130, superheated steam zone 140 and saturated vapour district 150 (Figure 35).Condensed steam is released from the top layer of saturated vapour district and gas compartment and wall.Heated bitumen releases (Figure 35) from the top layer of described room and the heated bitumen district at wall and combustion front edge.Condensed water and heated bitumen 8 are collected by lower horizontal well and are transported (or pumping) to surface (Figure 36).

Burning incoagulable gas 22 is collected and removes (Figure 36,31) by exhaust shaft or at the exhaust position be separated.Can (partly) be controlled independent of the operation pressure of liquid exploitation rate by the generation of exhaust.The generation of exhaust 22 also can be used for the direction and the speed that affect gas compartment growth.

The present invention relates to the application of SAGDOX technique in small property oil asphalt reservoir (i.e. thin oil-producing area).

Summary of the invention

According to an aspect, provide the method for liquid hydrocarbon of being gathered from the thin oil-producing area of at least one hydrocarbon bitumen reservoir by substantially horizontal recovery well, wherein said hydrocarbon bitumen reservoir also comprises top layer and bottom; Described method comprises the SAGD (SAGDOX) using oxygen, wherein:

I) by the described hydrocarbon bitumen reservoir above recovery well substantially horizontal described in steam injection;

Ii) oxygen is injected the described hydrocarbon bitumen reservoir above described substantially horizontal recovery well; With

Iii) by gravity drainage, liquid hydrocarbon is gathered in described substantially horizontal recovery well.

Preferably, at least one thin oil-producing area described is separated with described hydrocarbon reservoir, within making fluid stream be comprised in a described thin oil-producing area.

Preferably, by near at least one thin oil-producing area described in described steam injection.

Preferably, described oxygen is injected near at least one thin oil-producing area described.

More preferably, described steam and described both oxygen are injected near at least one thin oil-producing area described.

More preferably, described oxygen and described steam are injected described reservoir with the ratio of about 0.05 to 1.00v/v, preferably near at least one thin oil-producing area described.

In one embodiment, described substantially horizontal well also comprises toe section and follows section.Preferably, described toe section is in the first level of described reservoir and described the second level being in described reservoir with section.More preferably, described with section closer to the bottom of described reservoir and the described toe section described top layer closer to described reservoir.

In another embodiment, the geometry of described SAGDOX be selected from toe-to-with SAGDOX (" THSAGDOX ") geometry and individual well SAGDOX (" SWSAGDOX ") geometry.

Preferably, at least one thin oil-producing area described has the thickness being less than about 25 meters.More preferably, at least one thin oil-producing area described has the thickness being less than about 15 meters.

Preferably, described substantially horizontal recovery well is used for recovered water and liquid hydrocarbon, and in described reservoir bottom completion within 2 meters.

Preferably, by steam injection within described substantially horizontal recovery well 20 meters, and oxygen is injected within described substantially horizontal recovery well 50 meters; Wherein said substantially horizontal recovery well also comprises the punch block that at least one length is less than 50 meters.

In one embodiment, the injection of oxygen and steam is controlled in oxygen: the ratio of steam is in the scope of 0.05 to 1.00 (v/v).

Preferably, the ratio of oxygen and steam increases in described procedure, and described oxygen/steam ratio (v/v) is maximized at the end of close to described method.

In another embodiment, described THSAGDOX also comprises the toe section of protuberance (uplift) in described substantially horizontal recovery well.

According to an aspect, provide the method for liquid hydrocarbon of being gathered from hydrocarbon bitumen reservoir by substantially horizontal recovery well, wherein said hydrocarbon bitumen reservoir has at least one thin oil-producing area, top layer and bottom, preferably at least one thickness be less than about 25 meters containing pitch region, thin oil-producing area; Described method comprise be selected from toe-to-with the SAGD (SAGDOX) of the use oxygen of SAGDOX (THSAGDOX) and individual well SAGDOX (SWSAGDOX).

In one embodiment, described substantially horizontal well also comprises toe section and follows section.Preferably, described toe section is in the first level of described reservoir and described the second level being in described reservoir with section.Preferably, described with section closer to described bottom and described toe section closer to described top layer.

In one embodiment, described SAGDOX is THSAGDOX, more preferably described THSAGDOX also comprise described in there is the horizontal well of protuberance toe section.

In another embodiment, described SAGDOX is SWSAGDOX.

In one embodiment, described horizon mining well completion within described bottom about 2 meters.

In another embodiment, inject near described horizon mining well by steam by least one steam injection well, described steam injection well is preferably within dried up flat recovery well about 20 meters.

In another embodiment, oxygen (preferred oxygen-containing gas) is injected near described horizon mining well by least one oxygen Injection Well, described steam injection well preferably within about 50 meters, described horizon mining well, with perforation (contact) district more preferably there is length being less than about 50 meters.

In another embodiment, the ratio of oxygen and steam is controlled in the scope of 0.05 to 1.00 (v/v).

In another embodiment, the inert gas in the incoagulable gas and oxygen (exhaust) that produce by burning is removed by least one air exit, preferably removes respectively.Most preferably respectively from from described horizon mining well about 5 to about 75 meters of removals.

In another embodiment, at least one steam injection well described and at least one oxygen Injection Well described from least one air exit described at least about 100 meters.

In another embodiment, described reservoir tilts, and described horizon mining well is less than about 2 meters at its immediate point from the bottom of described reservoir.

In another embodiment, at least one steam injection well described and at least one oxygen-containing gas Injection Well described are within 10 meters of described horizon mining well.

In another embodiment, in the plane being substantially perpendicular to described horizon mining well, use at least one parallel, horizontal steam injection well by reservoir described in steam injection, described parallel, horizontal steam injection well is preferably the aboveground side of described horizon mining about 3 to about 8 meters.

In another embodiment, the well of the perpendicular using at least one single, the well of preferred multiple perpendicular injects described steam.

In another embodiment, the well of the perpendicular using at least one single, oxygen-containing gas is injected described reservoir by preferred multiple vertical well substantially.

In another embodiment, the well of the perpendicular using at least one single, exhaust is removed from described reservoir by the well of preferred multiple perpendicular.

In another embodiment, described steam and oxygen-containing gas are preferably mixed on earth's surface, and the well of the perpendicular using at least one single, the well of preferred multiple perpendicular injects reservoir.

In another embodiment, described steam and oxygen-containing gas are preferably by least one packer, be substantially separated more particularly by multiple packer, and the well preferably by least one single perpendicular, the well more particularly by multiple perpendicular inject described reservoir respectively.

In another embodiment, described steam and oxygen-containing gas use concentric tube to be substantially separated with packer, steam in preferred center pipe is surrounded by the oxygen-containing gas in adjacent ring, and preferably oxygen-containing gas injects described reservoir with the height higher than described steam injection height.

In another embodiment, use the well of single perpendicular that steam and oxygen-containing gas are injected described reservoir, well completion within about 50 meters, the toe from described horizon mining well of wherein said single perpendicular.

In another embodiment, use the toe section of the separation of described horizon mining well to realize the injection of described oxygen-containing gas.

In another embodiment, the eseparation ring section of following in the ascent stage that position is described horizontal well is removed in exhaust.

In another embodiment, described steam and oxygen-containing gas mix on earth's surface and use the toe section be separated of described horizontal well to inject described reservoir.

In another embodiment, described oxygen-containing gas and steam are substantially separated and inject described reservoir from the toe section of the separation of described horizontal well simultaneously.

Preferably described oxygen-containing gas and steam are separated substantially by using concentric tube and packer, and described concentric tube also comprises central tube and adjacent ring, and the steam in described central tube is surrounded by the oxygen-containing gas in described adjacent ring.

In another embodiment, described exhaust is removed following in the eseparation ring in the ascent stage of described horizontal well.

In another embodiment, by the toe up-hole of described horizon mining well and completion, make minimum injection aperture (for inject at least one of steam and oxygen-containing gas and the two) higher than the horizontal plane of the horizontal segment of described horizon mining well more than 2 meters.

In another embodiment, described horizon mining well is parallel to the boring of described reservoir bottom with updip (up-dip) direction in inclination reservoir, makes minimum injection aperture in height high more than 2 meters than the highest liquid exploitation aperture.

In a preferred embodiment, the oxygen in oxygen-containing gas and the ratio of steam increase in the maturation of described technique, and the ratio of described oxygen and steam (v/v) is maximized at the end of described process lifetime.

In a preferred embodiment, the extension tube of the toe near described horizon mining well is used, preferably to guarantee that the minimum pressure in described recovery well is near described toe.

Preferably, described exhaust shaft (position) and steam/oxygen gas Injection Well separate at least 100 meters.

In one embodiment, the oxygen of described oxygen-containing gas to be oxygen content be 95 to 99.9 (v/v) %.

In another embodiment, described oxygen-containing gas is air, and preferably oxygen content is the oxygen-enriched air of 21 to 95 (v/v) %.

In one embodiment, described hydrocarbon liquid is pitch (API density < 10; Original position viscosity > 100,000cp).

In another embodiment, described hydrocarbon liquid is mink cell focus (10 < API < 20; Original position viscosity 1000cp.)

In one embodiment, described substantially horizontal recovery well has the length being greater than 1000 meters.

brief Description Of Drawings

Fig. 1 describes traditional SAGD geometry.

Fig. 2 describes the well pattern end-view of SAGD life cycle.

Fig. 3 describes the character of saturated vapour.

Fig. 4 describes the pressure of saturated vapour and the relation of temperature.

Fig. 5 describes the asphalt viscosity of LongLake pitch and the relation of temperature.

Fig. 6 describes the Gravdrain equation of SAGD asphalt production rate.

Fig. 7 describe residual bitumen mark and saturated-steam temperature in the hole of residual bitumen in steam-purge zone and etc. the relation of the hydrostatic degree of depth.

Fig. 8 describes SAGD waterpower limit.

Fig. 9 describes the top layer on McMurray stratum.

Figure 10 describes the thickness on McMurray stratum.

Figure 11 describes the porosity interval on McMurray stratum.

Figure 12 describes the pitch oil-producing area thickness on McMurray stratum.

Figure 13 describes the API gravity on McMurray stratum.

Figure 14 describes traditional SAGD and to gather geometry.

Figure 15 describes a SAGD geometry of gathering for thin oil-producing area.

Figure 16 describes the 2nd SAGD geometry of gathering for thin oil-producing area.

Figure 17 describes the Three S's AGD geometry of gathering for thin oil-producing area.

Figure 18 describes simple SAGD model.

The relation of the pitch of not gathering at the end of Figure 19 describes process lifetime and clean oil-producing area thickness.

Figure 20 describes SWSAGD schematic diagram and well structure (band packer).

Figure 21 describes SWSAGD schematic diagram and well structure (not being with packer).

Figure 22 describes the THAI geometry for ISC.

Figure 23 describes the COGD/COSH geometry for ISC.

Figure 23 (a) describe according to of the present invention there is biased packer and steam with oxygen mix and the embodiment of the SWSAGDOX be separated.

Figure 24 describes according to typical SAGDOX geometry of the present invention.

Figure 25 describes the SWSF geometry for SWSAGD, SWSAGDOX, SWSF (U) and SWSAGDOX (U).

Figure 26 describes the first embodiment according to THSAGDOX of the present invention.

Figure 27 describes the second embodiment according to THSAGDOX of the present invention.

Figure 28 describes the 3rd embodiment according to THSAGDOX of the present invention.

Figure 29 describes the 4th embodiment according to THSAGDOX structure of the present invention and piping schematic.

Figure 30 describes the embodiment according to SWSAGDOX of the present invention (U) schematic diagram and relevant piping schematic.

Figure 31 describes the second embodiment according to the schematic diagram of SWSAGDOX of the present invention (U) and relevant piping schematic.

Figure 32 describes the embodiment constructed according to SWSAGDOX of the present invention.

Figure 33 describe according to of the present invention there is centralization packer and steam with oxygen premixed, be separated and be separated and the embodiment of the SWSAGDOX isolated.

Figure 34 describes the relation of HHV and the H/C ratio of fuel.

Figure 35 describes typical SAGDOX process mechanism.

Figure 36 describes typical THSF.

Figure 37 describes the minimum air flux rate of ISC.

Figure 38 describes steam and oxygen combustion pipe test I I.

Figure 39 describes according to three kinds of SAGDOX geometries of the present invention.

Figure 40 describes the many wells THSAGDOX geometry injected at the toe of recovery well according to primary steam of the present invention and oxygen.

Figure 41 describes conventional ISC.

Figure 42 describes the well pattern of gathering of the gas compartment in each stage of THSAGDOX.

Figure 43 describes the many wells THSAGDOX geometry injected at the middle part of recovery well according to primary steam of the present invention and oxygen.

Figure 44 describes according to many wells THSAGDOX geometry with alternately oxygen/steam and exhaust shaft of the present invention.

Figure 45 describes the waterpower limit of SWSAGDOX and SWSAGDOX (U).

Figure 46 describes typical SWSAGD (U) schematic diagram and relevant piping schematic.

Figure 47 describes oxygen channel and pipe design.

Figure 48 describes according to the embodiment with the THSAGDOX of the shared Injection Well of oxygen and steam of the present invention.

Figure 49 describes the embodiment according to the SWSAGDOX geometry in the thin oil-producing area of inclination of the present invention.

Figure 50 describes and declines with the THSAGDOX liquid level at toe place following of recovery well.

Figure 51 describes the SWSAGD in inclination oil-producing area.

Figure 52 describes the SWSAGD in inclination oil-producing area.

Figure 53 describes the TH geometry for THSF, THISC (or THAI) and THSAGDOX.

Figure 54 describes SWISC technique.

Figure 55 describes the THSF with shared Injection Well.

Figure 56 describes steam and oxygen combustion pipe test I.

Figure 57 describes according to Mitsui THSAGDOX geometry of the present invention.

detailed Description Of The Invention

In thin oil-producing area, the preferred parameter of SAGDOX geometry of the present invention comprises following:

(1) oxygen (instead of air) is used to inject as oxidant

If count process exhaust to remove sulphur component and the cost of volatile hydrocarbon of gathering, then for the energy that per unit is delivered to reservoir, even if at low pressures, the complete cost of oxygen is also less than compressed-air actuated cost.

Send for identical energy, oxygen occupies the volume of about 1/5th compared with air.Well conduit/Guan Geng little, and oxygen can be transported to from the farther distance in central plant position.

The situ combustion (ISC) of oxygen is used mainly to produce not with the incoagulability CO of nitrogen dilution ₂.CO ₂pitch can be dissolved in boost productivity.Dissolve by using oxygen and maximize.

When using oxygen, if exhaust main CO ₂and can be used for burying (sequestration).

There is minimum oxygen flow to maintain HTO burning (Figure 37)

More easily reach/maintain this flow using oxygen

(2) oxygen is kept to inject at concentrated position

Due to the minimum O from situ combustion ₂traffic constraints (Figure 37), thus oxygen Injection Well (or segregation section) contact with reservoir should more than 50 meters.

(3) oxygen separation and steam injection thing as far as possible

Condensed steam (hot water) is very strong to the corrosivity of carbon steel with oxygen.

In order to minimum corrosion, or 1) oxygen 26 and steam 6 are injected (Figure 36,26) respectively; 2) steam 6 and the oxygen 26 that mix limitedly are exposed to corrosion resisting alloy duct section; 3) integrality of this section is to described technique inessential (Figure 31 (b)); Or 4) whole injection band is corrosion resisting alloy (Figure 31 (a)).

(4) exhaust shaft (or position) is near reservoir top layer, away from oxygen injection phase.

Due to movement and the condensation of steam, incoagulable gas concentrates near the top layer of gas compartment.

Exhaust shaft should away from oxygen Injection Well with allow burning time/space.

(5) exhaust should not produce with significant oxygen content

Explode for alleviating and cultivate good oxygen utilization, any have be greater than 5% (v/v) oxygen content exhaust produce should be closed.

(6) steam reaching in reservoir/minimally measure

In SAGDOX, add/inject steam with oxygen, because steam assisted burning.Its pre-heat reservori, makes the igniting of HTO can be spontaneous.It adds OH to combustion zone ^-and H ⁺free radical is to improve and stabilizing burning (Figure 56 and Figure 38, Moore (1994)).This have also been obtained the confirmation of the operation of smokeless combustion, wherein adds steam and burns to improve and reduce smog (Stone (2012), EPA (2012), Shore (1996)).This technique for vaporising fuel also adds steam to minimize the generation (Berkowitz (1997)) of cigarette ash to partial combustion device.

Steam also condensation produce " covering " horizon mining well and this well and gas or steam are invaded the water of isolating.

Water is added recovery well to improve liquidity energy---water/asphalt emulsion---compared with independent pitch by steam condensate.

Steam is also heat transfer agent excellent in reservoir.When comparing hot combustion gas (mainly CO ₂) with steam time, the heat transfer advantages of steam is obvious.Such as, if the edge of hot gas room is about 200 DEG C, then burning gases are cooled to the available heat of 200 DEG C for about 16BTU/SCF from 500 DEG C.The saturated vapour of same volume contains the latent heat of 39BTU/SCF, and the twice exceeding combustion gas energy content is many.In addition, when hot combustion gas cools, they become effective slider, hinder and conduct heat further.When steam is condensed to send latent heat, it create of short duration low pressure, described low pressure is drawn into more steam---there is no the heat pump of plumbing installation.Kinetics is also conducive to steam/water.Be about 6.8 water coefficient of thermal conductivity (mW/cmK) compared with---high more than 20 times, the thermal conductivity of burning gases is about 0.31 (mW/cmK).Due to these factors, the subject under discussion that the side direction that burning (without steam) has slow heat transfer and difference increases.These subjects under discussion can be relaxed by steam injection.

Due to the amount of steam in reservoir cannot be measured, so SAGDOX arranges steam minimum value by the oxygen of 50% (v/v) in maximum oxygen/steam (v/v) ratio of 1.0 or steam and oxygen mixture.

(7) reach (or exceeding) minimum oxygen to inject

Lower than the oxygen of about 5% (v/v) in steam and oxygen mixture, burning purge zone is little and oxygen cost advantage is minimum.In this level, only have an appointment 1/3rd Implantation Energy be due to burning.

(8) maximum oxygen injects

In the constraint of above-mentioned (6) and (7), because per unit energy oxygen is expensive not as steam, institute is maximization oxygen/steam ratio for the selection of the least cost of exploitation pitch.

(9) preferred SAGDOX geometry is used

According to individual applications, reservoir matrix character, properties of fluid in bearing stratum, the degree of depth, clean oil-producing area, pressure and positional factor, there are three kinds of preferred geometries (Figure 39 a-c) for SAGDOX.

For small property oil area resource, 39b (THSAGDOX) and 39c (SWSAGDOX) is most preferred, only requires a horizontal well.Compared with SAGD, THSAGDOX and SWSAGDOX has the well number of minimizing and lower drilling cost.And interior pipe and packer should can be used for multiple application.

(10) by controlling SAGDOX/operate as follows:

I extraction fluid temperature (F.T.) and saturated-steam temperature, for the cold control of mistake of fluid exploitation rate, are wherein made comparisons by () under reservoir pressure.This is the gas mainly steam supposing to be close to above liquid/gas interface.

(ii) adjust oxygen/steam ratio (v/v) to meet target rate, its according to 0.05 to 1.00 range limits

(iii) regulate exhaust to remove speed and make gas mainly incoagulable gas, oxygen content is less than 5.0% (v/v), and reach/keep pressure target.

(iv) with above-mentioned (iii) steam regulation and oxygen charge velocity (according to above-mentioned (ii)) in the lump, reaching/keep pressure target.

THSAGDOX

Gather although SAGDOX also can be used for thin oil-producing area pitch, paired horizontal well (Figure 36) is difficult to be adapted in the limit of small property oil area resource, and well number rises compared with SAGD and capital cost also rises.

THSAGDOX (toe-to-with SAGDOX) and be preferred SAGDOX form, go for thin oil-producing area EOR, it uses the mixture of steam 6 and oxygen 26 instead of independent steam to carry out supplying energy.Keep the horizontal liquid recovery well of SAGDOX (and SAGD) that pitch draining can be realized in short path.Steam is easier than heated bitumen much mobile, and therefore the horizontal steam of SAGDOX or SAGD injects and replaced with oxygen 26 by peupendicular hole injection steam 6, and wherein oxygen 26 preferably injects near the top layer of oil-producing area.Be vented 22 (incoagulability burning gases) or removed by the peupendicular hole of single or multiple separation, or removing in the separate section (ring) of the vertical section near horizon mining well.The removal of exhaust 22 is preferably carried out near the top layer of clean oil-producing area.

Vertical oxygen/steam injection well is designed to 1) separate vapour 6 and oxygen 26 is with minimum corrosion and 2) near the top layer of oil-producing area, preferably inject oxygen 26 and inject steam 6 near the lower region of oil-producing area.This has extra benefit: are good hot sliders around the oxygen 6 in the ring of steam injection well casing, and is transported to reservoir by from well head along with steam, and this will stop/minimize from steam to tectal heat waste.

Figure 26,27,28,40 and 57 demonstrates the schematic diagram of various THSAGDOX process program.Figure 29 demonstrates the piping schematic going for all these technology types.

Described technique by production of water horizontal well flowing steam 6 and in peupendicular hole cyclic steam 6 (handling up) until the mutual UNICOM of well (namely fluid is from a well stream to another well) starts.After setting up UNICOM, well is converted to THSAGDOX and operates and inject steam 6 and oxygen 26 and recovered water/pitch 8 and be vented 22.

THSAGDOX horizon mining well is comparable, and to have the SAGD well of identical asphalt production rate longer, because less water flows in well.The multiple peupendicular hole form that Figure 40,41 and 57 demonstrates THSAGDOX more easily starts to facilitate longer horizontal well or shorter well and operates.Along with burning leading portion is from toe the following mobile (Figure 42) towards horizontal well near horizontal well, the different vertical well near toe steam/oxygen gas Injection Well is used as exhaust removal well at first and is converted to steam/oxygen gas Injection Well subsequently.This makes it possible to start fast in technical maturity process and improve uniformity.

Another form of this scheme starts burning near horizontal well mid point, and combustion front is simultaneously towards the toe of horizon mining well with mobile (Figure 41).

The feature of these THSAGDOX process programs comprises following:

Keep O ₂inject the separation between exhaust removal.Exhaust shaft can be used for the uniformity of the ISC process portion of control THSAGDOX.

This technique increases three-dimensional micromodule mechanism (overflow), forces longitudinal reservoir to flow by geometry.

This technique is by reducing well number, reducing well length, using peupendicular hole instead of horizontal well or reduce capital cost by reducing well size (diameter).

This technique reduces running cost.Per unit is delivered to the energy of reservoir, oxygen is more cheap than steam.

This technique can use gradual change type oxygen strategy, and wherein oxygen concentration increases to reduce cost in project life, extends the use project life-span and improve pitch to gather.

If necessary, this technique can use pump to assist exploitation pitch and water in horizontal well.

This technique is by extraction more water compared with steam injection.Connate water will in burning purge zone evaporation (Figure 35).Water also produces as combustion product.According to the leakage in reservoir or reserved rate, THSAGDOX may produce than its more water as steam injection.

Hot combustion gas by backflow some water to keep water/steam stock good in reservoir.

This technique also keeps all SAGDOX benefits.

The carbon dioxide produced as combustion product concentrates (or dissolve/be concentrated in liquid product stream) and should be suitable for burying in exhaust.

Oxygen can from remote position Cemented filling and do not have energy loss economically.

The water produced by steam injection can be assisted level of isolation recovery well and be minimized the intrusion of incoagulable gas to this well.

If steam in interior pipe and oxygen in ring, then the peupendicular hole for oxygen and steam injection can minimal thermal losses.Oxygen is that good slider is to keep the heat in steam.Preferred steam injection is in mesotube and oxygen surrounds steam (Figure 29) as slider.

Particularly for this reason, the conversion that can enlighten THSAGDOX to pure burning (ISC) EOR technique is suitable, because oxygen is lower than steam cost as energy source heating reservoir bitumen.But retaining steam as infusion is expect, because:

Steam makes flameholding and improves kinetics of combustion

Steam preheating combustion zone

Steam serves as good heat transfer medium---be better than hot combustion gas (heat pump effect)

Steam can cause side direction to increase (problems in some ISC techniques)

Steam can assist cover/seal recovery well and suppress incoagulable gas to be penetrated into described well upon condensation

Steam/water can be refluxed by hot combustion product

In recovery well, water/asphalt mixture has the viscosity lower than pitch itself.

Steam injection increases the size of steam-purge zone, to assist to guarantee that burning focuses on residual bitumen (coke)

Steam is burning creation flow path.

Also can enlighten, the injection of water (instead of steam) produces steam at reservoir and improves the better mode of energy efficiency.Water can remove the heat (Figure 35) of spontaneous combustion purge zone to produce steam in position, instead of uses fuel to produce steam in the boiler on surface.This uses vertical injection wells/recovery well to realize the preferred embodiment (Figure 43) of wet combustion.But due to following reason, being used in steam overflow overflow (SFOXT) geometry utilizing oxygen in the reservoir of thin oil-producing area is not good idea:

Compared with ISC geometry (Figure 43), the flow path in SAGDOX geometry from Injection Well to recovery well is very short.If use vertical injection wells to inject water (Figure 29), water will be easy to walk around this technique and flow directly to recovery well.

Or if combustion front is close to Injection Well, then water can make sudden the fighting of burning cause low-temperature oxidation (LTO) to start.

Can enlighten, because the hot-zone in THSAGDOX is positioned at oxygen 26 injection region and then advances (Figure 42) towards the toe of horizontal well, the pitch exploitation rate that it is expected to THSAGDOX is less than SAGD, and wherein vaporium increases (Fig. 2) along the length of horizon mining well simultaneously.THSAGDOX, by producing heat at the temperature higher than steam, by steam 6 is used as heat transfer agent, and compensate for this problem by some steam of backflow.This is also by using multiple oxygen 26 injection phase to improve (Figure 44), make burning can along well propagate and multiple burning position will increase simultaneously.

Because every barrel of pitch produces less water, compared with SAGD horizontal well, the horizontal FIH of THSAGDOX is less, therefore, depend on the oxygen level in infusion gas, for identical pressure drop, THSAGDOX horizontal well can longer than the SAGD horizontal well of same size (being about 2500 meters most).

SWSAGDOX

THSAGDOX is thin oil-producing area pitch EOR more better than SAGD, because compared with SAGD (2 horizontal wells), its well number and cost reduction (1 horizontal well+1 peupendicular hole, wherein peupendicular hole can be shared between well pattern), and reduced by the energy cost using oxygen to carry out burning.Along with oil-producing area thickness reduces, the capital cost of THSAGDOX may be too high and be not enough to the reasonability confirming pitch EOR.

The another kind of form of SAGDOX is called SWSAGDOX (individual well SAGDOX), and it can even cut down more costs.This technique uses single horizontal well to realize SAGDOX technique.Use concentric tube and is separated packer 18 to be separated the part of this well, inject for steam 6 and oxygen 26 and for pitch/water 8 be vented 22 extraction (Figure 30,31a-e).By reducing well number (until 1) and by may reclaim and reuse the two and reduce capital cost various well completion assemblies (packer and pipe).

The simplest form of SWSAGDOX is as shown in Figure 31 (a), and wherein steam and oxygen 30 mix on surface and inject and carries out premix, instead of relies in reservoir and mix.In order to resist corrosion, the ascending pipe 30 for oxygen and vapour mixture is alloy steel or other resistant materials.In order to avoid the replacement scheme of corroding to be make this oxygen+vapour mixture 30 overheated to stop steam condensation on infusion tube wall.From the heat waste of this mixture, especially for dark thin oil-producing area bitumen reservoir, it may be a subject under discussion.The toe 40 (Figure 31 (a)) of horizontal well is also exposed to oxygen+aqueous corrosion.But the integrality in this Jing Zhi district is not crucial for EOR technique.

Use pipe to come oxygen separation and steam 30 to the improvement (Figure 31 (b)) of this design, and oxygen 26 surround steam injection well casing.Oxygen 26 serves as the good slider of steam pipe and reduces heat waste to maintain quality of steam.But the toe district 40 of horizontal well is still exposed to steam+oxygen corrosion.

Another improves as shown in Figure 31 (c), before entering reservoir, wherein use packer 18 to come oxygen separation and steam 30.This can minimize toe corrosion and still completely cut off steamline to reduce heat waste.

Another embodiment be use resistant material to horizontal well, be at least that the toe section of well carries out completion.

Another subject under discussion (Figure 30,31a-e) of SWSAGDOX is that steam injects in identical with petroleum liquid (level) level.SAGD, by making exploitation Injection Well completion (Fig. 1) with the biased spacing of about 5 meters and controlling the vapor/liquid interface (Fig. 8) of this technique between Injection Well and recovery well, stops steam to be penetrated into the overflow of recovery well or steam injection well.This interface is tilted by the pressure drop in recovery well, but utilizes good operation, and it stops the overflow of steam by-pass and Injection Well.The peak at this interface is at the toe place of horizontal well.

This is crossed cold strategy and can be kept by injecting steam (with oxygen) above the plane of horizon mining well by SAGDOX and THSAGDOX.

But in SWSAGDOX (Figure 45), if the section of steam 6+ oxygen 26 is flat, and this technique of operation makes liquid covering production section penetrate to avoid steam 6+ oxygen 26, so horizontal well overflow the most at last.Suppression steam 6+ oxygen 26 injects and endangers uniformity by this.If by eliminating this problem with the liquid of speed extraction faster, so whole production section may stand penetrating of steam 6 and oxygen 26.

The bottom of Figure 45 and Figure 25,32, the schemes of 33 and 46 displays hole and make horizontal well completion, make toe section be inclined upwardly oil-producing area top layer near.This makes it possible to keep the horizontal production section of liquid covering, makes oxygen 26 and steam 6 not be penetrated into recovery well and oxygen 26 and steam 6 are injected above liquid surface 12, making to inject not overflow (Figure 45).The technique with this geometry is called SWSAGDOX (U), and wherein U represents the toe district protuberance of horizontal well.This is preferred SWSAGDOX geometry.

SWSAGDOX technique has the advantage of THSAGDOX technique, and following further feature:

In horizontal well, pipe can reclaim and reuse, and makes its cost can intersperse among several technique unit.

This is least cost selection (capital cost) of thin oil-producing area steam+oxygen EOR

This is that most The Small Well number is selected

This technique has the longitudinal stream using and drive the mechanism of gathering

If if well is up-hole to updip direction boring or the toe of well, so the production section of well can be isolated by fluid exploitation

If pump is necessary, so it can be received (such as, Figure 31 (a))

Design keeps exhaust separately to remove

If steam 6 occupies central ascending pipe, so oxygen 26 can assist isolated steam pipe and minimal thermal losses (Figure 31 a-e)

SWSAGDOX (U) form of this technique allows liquid to cover horizontal production section to stop or to suppress gas penetration (steam, oxygen, burning gases), and, meanwhile, this gas inject district (steam+oxygen) is not by liquid flooding.

The geometry (Figure 30) of SWSAGDOX and the geometry similar (Figure 20) of SWSAGD, but there is following process distinction:

SWSAGDOX uses steam+oxygen to inject.SWSAGD only uses steam

SWSAGD injects steam on the height identical with exploitation.The preferred form (Figure 32) of SWSAGDOX injects steam and oxygen on the height higher than liquid exploitation.

The on-the-spot test of SWSAGD is disappointing.

SWSAGD focuses on mink cell focus EOR instead of pitch.

SWSAGD pays close attention to from steam injection well to the heat leak of extraction fluid and promotes the exploitation for the instlated tubular of steam injection.SWSAGDOX uses the oxygen in ring to isolate steam pipe (Figure 31 B).

Because oxygen has about 10 times to the energy density of steam, the pipeline of SWSAGDOX can be more much smaller than the pipeline of SWSAGD.

SWSAGD is saturated vapour technique.Temperature limited in the character of saturated vapour.At the same pressure, SWSAGDOX will operate at the temperature higher than SWSAGD.

An important issue of SAGDOX and SWSAGDOX uses the packer that can at high temperature operate to isolate zones of different.This is the active area (Haliburton that oil supply business develops, " ZonalIsolationforSteamInjection... " website, in May, 2012) (Schlumberger, " PackerSystems ", website, in May, 2012).This is also geothermal industry special concern, the comparable EOR of condition of there is harsher and have corrosivity (DOE " EnhancedGeothermalSystemsWellfieldConstructionWorkshop " SanFrancisco, on October 16th, 2007).Also developing the small-sized self sealss packer (OGJ " Self-SettingThermalPacketsHelpCyclicSteam " 1998) for more The Small Well size.

Current techniques (-2012) can be used for comparatively large pipeline size and the highest 600 °F (316 DEG C) (Haliburton (2012)) and can be used for the hot packer of small pipeline packer the highest 400 DEG C (OGJ (1998)).For the pressure exceeding the expection of SAGDOX and SWSAGDOX technique, wiper seal is graded.Most of packer is callable and can repeatedly uses.Small pipeline packer is operating (OGJ (1998)) in the highest 5000 pressure cycle/year at the scene.

Hot packer for SAGDOX and SWSAGDOX technique is routine techniques available at present.

Depend on technological design, SAGDOX and related process (THSAGDOX, SWSAGDOX, SWSAGDOX (U)) can have the well number higher than SAGD.This can by use SAGDOX reduce line size and partly (or fully) biased.The minimizing of line size is due to 2 factors---oxygen contains and the energy content (table 2) of vapor phase than about 10 times; Also because for identical energy injection speed, SAGDOX injects the steam more less than SAGD, and for identical pitch exploitation rate, extraction fluid (water+pitch) can be less than SAGD fluid.

Suppose the following pipe design standard for shallow SAGD project:

The asphalt production rate of (i) 500 barrels/day.

(ii) every barrel of pitch 1MMBTU energy demand (SOR ~ 3)

(iii) steam of 1000BTU/ pound thermal content

(iv) 100psia, 160 DEG C of steam injections (50 meters of degree of depth hydrostatic pressures (Fig. 4))

V () steam injection is designed to 25 feet per seconds

(iv) liquid (water+pitch) exploitation is 1 feet per second

(vii) all steam injections are as hot water extraction

Then can calculate SAGD project, under reservoir conditions, steam demand is 500,000 lb/day=1428.6 barrels/day=28.57CF/ second.Use above-mentioned design standard, steam injection well conduit has the diameter of 7.23 inches and production tubing has 4.79 inch diameters.

This is applied to the SAGDOX relevant item under the same terms, Figure 47 demonstrates the pipe flow speed limit of the oxygen delivery design adopting carbon steel or stainless steel tube, and wherein potential particles hit is limit---the worst case (AsiaIndustrialGasesAssociation " OxygenPipelineSystems " 2005) of design.Except above, below we can suppose:

I () be (Figure 47) under downhole conditions, the oxygen velocity design of 100 feet per seconds

(ii) SAGDOX (35) mixture is used, 35% oxygen (v/v) in Steam oxygen mixing; The heat of 84.5% is injected from oxygen combustion (table 2)

Then the line size for delivering oxygen and steam in the pipeline separated can be calculated.Oxygen demand is 880MSCFD=3.36 ton/sky.

Under reservoir conditions, steam demand drops to 77,500 lbs/day=221 barrels/day=4.18CF/ second.Diameter for the line size of oxygen injection is 2.09 inches.Diameter for the line size of steam injection is 2.76 inches.

If steam and oxygen transport in single pipeline (Figure 26,27,29), required total duct size is 3.47 inches (ignoring wall thickness).

Because less steam injection and less hydromining go out, so the also reduced size of recovery well.The diameter of the well size calculated is 2.93 inches.

SAGDOX related process also must extraction exhaust.Exhaust volume and oxygen injected slurry volume similar, adopt identical line size to require (diameter is 2.09 inches)

For pipeline, often suppose that capital cost is proportional to pipe diameter or is proportional to the accumulation pipe diameter of multi-pipeline.Identical work can be carried out at this, as follows:

SAGDOX form all has lower total pipeline diameter.All SWSAGDOX pipelines can remain single 5 " manages (disregarding pipe thickness).

The preferred embodiment of THSAGDOX and SWSAGDOX of the present invention depends on the character of target reservoir---specifically reservoir thickness, reservoir continuity, reservoir quality and depth of reservoirs.The preferred form of SWSAGDOX is the SWSAGDOX (U) with protuberance toe district.

The THSAGDOX of 3 kinds of forms is had to wait to consider:

(i) simple form (Figure 26), for single vertical injection wells completion near the toe of horizon mining well of oxygen 26 and steam 6, and the removal being vented 22 is realized by the separate section of the horizontal well of completion near the top layer that is used in oil-producing area.Tubes/conduits is simple, and oxygen 26 is sent with isolated steam pipe and minimal thermal losses in ring.The recovery well with exhaust 22 removal keeps the selection (Figure 29) if necessary then using submersible pump.This system can be applied to deposition (10 to 25 meters thick) best, preferably be separated from described reservoir, relatively int reservoir (seldom/there is no shale, poor district), and be applied to middle equicontinuity (the long 500-1000 rice of well).

If there is similar but more wide and int reservoir, so can have adjacent well pattern and well pattern can share peupendicular hole, the scheme of such as Figure 36 can share discharge well separately.This is not very expensive, and provides the prospect using the uniformity of discharge well separately to control.Another form as shown in Figure 48 allows to share vertical injection wells to reduce cost.

If there is similar deposition (10 to 25 meters thick) but we expect that some cause the formation damage of more poor efficiency expection, then preferably consider the longer horizontal well with multiple injection/discharge well, wherein said injection/discharge well depends on that performance can be converted to from injection discharges purposes (vice versa) (Figure 40,41,57).This at reservoir impaired or may impaired, to control for uniformity and Properties Control and production management provide extra flexibility.Productivity ratio does not need to be deteriorated, because we can use multiple Injection Well (Figure 44) and get out the horizontal well (500-2500 rice) longer than SAGD simultaneously.

Because well number reduces and reusable well completion assemblies (pipe, packer), so by using SWSAGDOX (U) technique shown in Figure 30,31a-e, 32,33,49 to develop the thinnest reservoir (5-15 rice) best.This technique does not make self to be suitable for well and shares (not having peupendicular hole), but capital cost should be minimized.

People also have the selection to THSAGDOX, are wherein extracted out from horizontal well by liquid.Traditional selection is from horizon mining Jing Gen district extracted liquid.But people also can use enlargement of pipe device to extract (Figure 29) out from toe.Advantage under toe illustrates in Figure 50.The steam injection well part of vertical injection wells can be stoped to be overflowed to liquid surface.

(1) difference (Figure 53) compared of THSAGDOX and THAI

THSAGDOX uses independent well or Disengagement zone to remove exhaust.THAI forces exhaust to produce at horizon mining well.

THSAGDOX operates in gravity drainage technique.Pressure reduction between gas inject and fluid product is very little.THAI operates as the displacement of reservoir oil (gas-powered) technique with remarkable pressure reduction between injection/recovery well.

THSAGDOX injects steam to improve burning, and uses liquid to cover recovery well to suppress gas penetration.THAI does not attempt adding steam or covering recovery well.Gas penetration is necessary for THAI technique.

THSAGDOX injects steam and oxygen as energy source in reservoir.

THAI injecting compressed air.

THSAGDOX covers recovery well and injects oxygen to stop oxygen penetration to recovery well in a high position.THAI relies on the mobile coke blocking of holding upstream to be formed before combustion in horizon mining well to stop air (oxygen) to penetrate.

THSAGDOX injects water (and backflow) steam and increases to encourage/to stimulate the side direction of heating region.THAI relies on hot combustion gas/heat conduction to carry out side direction growth.

The on-the-spot test history of THAI is disappointing.

THAI (now) focuses on mink cell focus EOR.THSAGDOX focuses on pitch EOR.

THSAGDOX can use cold control to guarantee not having gas or steam to penetrate or extraction to recovery well.

(2) SWSAGDOX (Figure 17,31,31 (a)) and SWSAGD (Figure 20) difference

SWSAGDOX uses the mixture of oxygen and steam that energy is delivered to reservoir.SWSAGD only uses steam.

Form (SWSAGDOX (U)) (Figure 32,33,45) that the toe up-hole that SWSAGDOX has wherein horizontal well is injected with separating liquid exploitation and steam/oxygen gas.SWSAGD has flat horizontal well completion, and the liquid wherein flowing to recovery well can make steam injection well kick (Figure 20 and 52)

SWSAGDOX and SWSAGD is as gravity drainage technological operation.But due to fuel assembly, the average temperature of the gas compartment of SWSAGDOX is higher than the saturated-steam temperature of SWSAGD.

The on-the-spot test history of SWSAGD is disappointing

Burning gases from SWSAGDOX move to the top layer regions (Figure 42) of gas compartment, and assist isolated interface to reduce heat waste.

SWSAGD focuses on thin oil-producing area mink cell focus EOR.SWSAGDOX focuses on thin oil-producing area pitch EOR.

(3) THSAGDOX (Figure 18) and/or SWSAGDOX (Figure 30,32) phase for the difference of SAGD (Fig. 1)

SAGD uses 2 parallel horizontal wells.THSAGDOX and SWSAGDOX only uses a horizontal well.

SAGD is two-dimentional technique---on the longitudinal direction of homogeneous reservoir, there is no longitudinal vapor/liquid stream.THSAGDOX and SWSAGDOX is three-dimensional process---GD room (gas and steam blowing district) increases (Figure 28) at longitudinal direction.

SAGD uses saturated vapour.THSAGDOX and SWSAGDOX injects the mixture (difference or common) of steam and oxygen.

SAGD's is temperature limited in saturated-steam temperature.The fuel assembly of THSAGDOX and SWSAGDOX produces heat at much higher temperature (600 DEG C contrast 200 DEG C) in reservoir.

SAGD steam can not the evaporation water (water in connate water, poor district in reservoir ...).THSAGDOX and SWSAGDOX can evaporate reservoir water.

SAGD steam is used for once by property technique.THSAGDOX and SWSAGDOX can recirculation water/steam.

SAGD is any connate water of not extraction substantially.THSAGDOX and SWSAGDOX is from burning-purge zone extraction connate water.

The cost of energy (saturated vapour) of SAGD is apparently higher than the cost of energy of THSAGDOX and SWSAGDOX.

SAGD is the clean user (recovered water recycling < 100%) of water.For higher oxygen level (>9%), THSAGDOX and SWSAGDOX is higher than SAGD.

SAGD has successful on-the-spot test.THSAGDOX and SWSAGDOX is still in the development phase.

SWSAGDOX and THSAGDOX is designed to focus on this oil-producing area pitch (such as <25 rice is thick).SAGD focuses on thicker oil-producing area (being greater than 15m)

SWSAGDOX and THSAGDOX can gather from steam blowing district pitch.

SAGD leaves significant residual bitumen behind steam blowing district.

Finally gathering of THSAGDOX is gathered more than SAGD, the pitch because THSAGDOX gathers from steam-purge zone and THSAGDOX can continue exploitation to higher ETOR value, because cost of energy is lower.

SAGD uses nitrogen dilution.If THSAGDOX exhaust main CO ₂, be applicable to burying (sequestration).

(4) THSAGDOX (Figure 26) is relative to the district of COSH/COGD (Figure 23) not

COSH has 3 horizontal wells+3 (or more) peupendicular hole/well pattern (Figure 23).THSAGDOX has single horizontal well and single peupendicular hole.

COSH relies on side direction horizontal discharge well to carry out stimulated side to growth.THSAGDOX relies on steam to carry out stimulated side to growth.

COSH has multiple vertical air Injection Well.THSAGDOX has single oxygen/steam injection well.

COSH uses compressed air as oxidant.THSAGDOX uses oxygen.

COSH and THSAGDOX does not carry out on-the-spot test.

If COSH exhaust main is through N ₂the CO of dilution ₂.THSAGDOX exhaust is undiluted CO ₂.

(5) specific characteristic of THSAGDOX:

Steam and oxygen inject altogether

O ₂the ratio ranges of/steam (v/v)

O ₂working in coordination with between/steam

Focus on bitumen reservoir (< 25 meters is thick, and preferred 10-25 rice is thick)

For the multiple well form (Figure 48,40,41,57) of longer horizontal well

Multiple combustion zones form (Figure 44)

The oxygen-barrier of steam injection line

Gradual change type oxygen strategy---increase oxygen with project maturation

Focus on oxygen and non-air

There is the TH geometry of multiple infusion, product.

(6) specific characteristic of SWSAGDOX:

Individual well technique, 2 infusions, 2 products

As the feature of above-mentioned (5), (except multiple well case)

Focus on thin reservoir

Updip completion form (Figure 49)

The toe form (Figure 30,31) of protuberance, SWSAGDOX (U)

The oxygen-barrier of steam injection line

Focus on bitumen reservoir, preferred thin reservoir (such as < 25 meters, more preferably < 15 meters) has the SW geometry of multiple infusion, product

table 1

asphaltene deposition economized by Alberta (10 ⁹ bucket)

1. originate---HeidrickandGodin (2006)

2. thin oil-producing area (boundary=10 meter)

3., owing to rounding up, numerical value possibly cannot be added

Table 2

sAGDOX injecting gas

Wherein:

(1) steam calorific value=1000BTU/ pound

(2) O ₂heat/fuel value=480BTU/SCFO ₂

(3) the pure steam of SAGD=

(4) 9% (v/v) oxygen in SAGDOX (9)=steam-oxygen mixture

Its scope is not deviated from due to thus many changes can be made to embodiments of the present invention.Think that all scenario comprised in this article is all considered to unrestricted to explanation of the present invention.

Claims (19)

1. gathered from the thin oil-producing area of at least one hydrocarbon bitumen reservoir by substantially horizontal recovery well the method for liquid hydrocarbon, wherein said hydrocarbon bitumen reservoir also comprises top layer and bottom; Described method comprises the SAGD (SAGDOX) using oxygen, wherein:

I) by the described hydrocarbon bitumen reservoir above recovery well substantially horizontal described in steam injection;

Ii) oxygen is injected the described hydrocarbon bitumen reservoir above described substantially horizontal recovery well; With

Iii) by gravity drainage, liquid hydrocarbon is gathered in described substantially horizontal recovery well.

2. method according to claim 1, wherein by near at least one thin oil-producing area described in described steam injection.

3. method according to claim 1, wherein injects described oxygen near at least one thin oil-producing area described.

4. method according to claim 2, wherein injects described oxygen near at least one thin oil-producing area described.

5. method according to claim 1, wherein injects described reservoir by described oxygen and described steam with the ratio of about 0.05 to 1.00v/v.

6. method according to claim 1, the well of wherein said basic horizontal also comprises toe section and follows section.

7. method according to claim 6, wherein said toe section is in the first level of described reservoir and described the second level being in described reservoir with section.

8. method according to claim 7, wherein said with section closer to the bottom of described reservoir and the described toe section described top layer closer to described reservoir.

9. method according to claim 1, wherein said SAGDOX have toe-to-with SAGDOX geometry.

10. method according to claim 1, wherein said SAGDOX has individual well SAGDOX geometry.

11. methods according to claim 1, at least one thin oil-producing area wherein said is separated with described hydrocarbon bitumen reservoir.

12. methods according to claim 1, at least one thin oil-producing area wherein said has the thickness being less than about 25 meters.

13. methods according to claim 1, at least one thin oil-producing area wherein said has the thickness being less than about 15 meters.

14. methods according to claim 1, wherein said substantially horizontal recovery well is used to recovered water and liquid hydrocarbon, and within 2 meters of described reservoir bottom completion.

15. methods according to claim 1, wherein by described steam injection within described substantially horizontal recovery well 20 meters.

16. methods according to claim 1, wherein inject within described substantially horizontal recovery well 50 meters by described oxygen; Wherein said substantially horizontal recovery well also comprises the punch block that at least one length is less than 50 meters.

17. methods according to claim 16, wherein said oxygen and steam are controlled in 0.05 to 1.00 (v/v) oxygen: in the scope of steam.

18. methods according to claim 17, the ratio of wherein said oxygen and steam increases in described procedure, and described oxygen/steam ratio (v/v) is maximized at the end of close to described method.

19. methods according to claim 9, wherein said THSAGDOX also comprises the toe section of protuberance in described substantially horizontal well.