CN1372067A - Method for thermal producing ultrathick oil by cyclic steam stimulation and special apparatus thereof - Google Patents

Abstract

The huff and puff thermal production method of high-viscosity crude includes the following steps: 1). lowering heat-insulating oil pipe, charging high-pressure nitrogen gas into the ring cavity between casing pipe and heat-insulating oil pipe, injecting steam, closing well and jetting; 2). lowering sucker-rod string and oil-production; 3). after oil production, taking out sucket-rod string, injecting steam and repeating the above-mentioned steps 2. Its special-purpose equipment includes an integrated pipe column formed from heat-insulating oil pipe and sucker-red string, said heat-insulating oil pipe possesses internal and external two-layer structure, between the heat-insualting oil pipe and casing pipe a ring cavity is formed, the sucker-rod string is a hollow suck-rod, its lower end is equipped with solid sucker-rod, rod pum and sand control screen structure.

Description

A kind of method for thermal producing ultrathick oil by cyclic steam stimulation and isolated plant

The present invention relates to ultra-thick oil thermal and adopt technology, specifically a kind of method for thermal producing ultrathick oil by cyclic steam stimulation and isolated plant.

In the prior art, the super heavy oil recovery method has multiple, mainly be that to annotate vapour, pump intermediate frequency electrical heating oil recovery more, the insulation of ground fire coal (or gas two-purpose) stove with vacuum heat insulation tube be the steam soak thermal recovery technology of core, it annotates vapour, two manufacturing processes of recovering the oil adopt two casing strings respectively, specifically be to annotate vapour to adopt instlated tubular, packer, telescoping tube tubing string, recover the oil to produce and adopt conventional oil tubing string, electrical heating hollow stem tubing string, the subject matter of existence is:

1. the super viscous crude cycle of handling up lacks, and operation is frequent.General super viscous crude was handled up the cycle at 70～100 days, conventional tubing string flow chart is many, as: following heat-proof string, rise, sand washing tubing string down, rise, tubing string down, rise, lower sucker rod, finish a thermal recovery operation and need 6 procedures shown in Figure 1 usually, to reach at most more than 12 roads, after the steam-stimulated well production cycle finishes, propose oil pipe and be lowered to instlated tubular; When changing next alternate water injection vapour over to, propose oil pipe again and be lowered to instlated tubular.Therefore, the partial heat energy loss is arranged, the activity duration is long, easily causes well-flushing and polluted reservoir, has increased the cleaning charge usefulness of instlated tubular and oil pipe again, also easily causes the well site to pollute; The ratio height of general job expense xanthenes oil cost, the oily operating cost of ton generally about 100 yuan, accounts for 20% of variable cost.

2. sealing is poor, and the sleeve pipe infringement is serious.In the prior art, adopt the packer sealing technology in the super heavy oil recovery device, handle up when annotating vapour, packer is by thermal expansion packing oil casing annular space, sleeve pipe produces the very large temperature difference up and down at packer card envelope place, causes card envelope place stress to concentrate, and sleeve pipe is damaged.The excessive packer that also easily causes of packer inflation is stuck, carries fixed tubular column and causes workover.In addition,, adopt and close sleeve pipe notes way of steam, do not have protective casing and the effect that reduces wellbore heat loss because thermal packer packing effect is bad.

3. heat waste is big in the oil recovery process, the energy consumption height.Super viscous crude production needs omnidistance companion's heat, adopts the intermediate frequency electrical heating at present, and actual power reaches 60～70kw.

In order to overcome above-mentioned deficiency, the purpose of this invention is to provide a kind of method for thermal producing ultrathick oil by cyclic steam stimulation and isolated plant that can reduce flow chart, reduce the oil recovery process heat waste.

Technical scheme of the present invention is:

Its method is operated as follows:

(1) thermal insulation tubing under fills high pressure nitrogen in sleeve pipe and thermal insulation tubing toroidal cavity, annotates vapour by the notes vapour amount of injection allocation, annotates vapour and finishes back stewing well, open flow then;

(2) rod string of band sand control screen and insert pump under, cable heating down in hollow rod is then recovered the oil;

(3) oil recovery finishes a back rod string, annotates vapour, repeating step (2);

Have sand grains enter insert pump/pipeline need the cleaning situation under, do sand washing with described thermal insulation tubing and operate in preceding the adding of step (1) back step (2); Need under the situation at the inspection pump, behind the oil recovery roofbolt, added the oil recovery roofbolt under step (2), the inspection pump descends oil recovery roofbolt operating procedure again;

The isolated plant of described method for thermal producing ultrathick oil by cyclic steam stimulation, place in the sleeve pipe, constitute variorum vapour by thermal insulation tubing and rod string and recover the oil insulation sand washing sand control in the integrated pipe column of one, wherein thermal insulation tubing is inside and outside double-layer structure, establish insulation layer between two-layer and be used for filling with insulation material, described thermal insulation tubing free end is installed together by rod-type pump seat envelope short circuit and sand washing nib, is ring cavity between sleeve pipe and thermal insulation tubing; Described rod string adds solid sucker rod, insert pump, sand control screen structure for the hollow rod lower end, wherein the change of hollow rod and solid sucker rod links and connects, insert pump is installed on the solid sucker rod by seat envelope mandrel, one fixture block top is connected with solid oil pick-up tube contact by spring, the bottom is stuck on the alternate open-work of distance on the connector of insert pump, one free end is installed at the bottom of the insert pump is established the sand control screen of plug, described sand control screen external diameter and insert pump coupling;

Described insert pump is made up of pump barrel, plunger, and embedded a connection piece in pump barrel top wherein, connector are provided with the alternate open-work of distance; Described fixture block top is connected by the contact of spring and solid sucker rod, and the bottom is stuck on the open-work on the connector, and the connector upper end is an one with a seat envelope mandrel that is set in the solid sucker rod outer wall, establishes a standing valve bottom the pump barrel, and the plunger lower end is provided with travelling valve;

Described rod-type pump seat envelope short circuit has the undergauge section, and the undergauge section is divided into a ring-shaped groove;

Be provided with sealing device between described connector and rod-type pump seat envelope short circuit; Described sealing device is poly-PTFE sealing ring.

The present invention has following advantage:

1. high efficiency.The inventive method cooperates thermal insulation tubing and insert pump is installed and the rod string of sand control screen has been realized notes vapour, oil recovery, insulation, sand washing and sand control function integration, whole supporting, significantly reduced loaded down with trivial details flow chart, avoided removing, heat-proof string, rise, sand washing tubing string down, rise, operation such as tubing string down, only need remove rod string, thereby realized the fixed tubular column operation, reduced operating cost.With time test of 48 wells is example, and time fixed tubular column sand washing of 7 wells takes place, and 1.2 ten thousand yuan of costs fall in more conventional sand washing individual well, and 7 mouthfuls of wells are saved 9.8 ten thousand yuan of costs.The test well cycle is on average saved 3.68 ten thousand yuan of operation costs, 877 tons of average produce oils of cycle, and production cost per tone oil descends 41.9 yuan, and the oily operating cost of average ton descends 39.5% for 106 yuan.Simultaneously, 1 cycle of handling up can shorten 3～4 days activity durations, and production efficiency doubles.

2. good heat-insulation effect.Thermal insulation tubing among the present invention has played heat insulation, the insulation double action of recovering the oil of notes vapour, its apparent heat conductivity is 0.01w/m. ℃, approaching with 0.008w/m. ℃ of vacuum heat insulation tube apparent heat conductivity, adopt the nitrogen-gas heat-insulating method, substitute packer and telescoping tube in the prior art, the present invention has guaranteed that annulus is in dry state between sleeve pipe and the thermal insulation tubing, and effect of heat insulation is good, simultaneously sleeve pipe has been played protective effect; Not good, the most well of sealing effectiveness that has also solved the heat insulation existence of packer in addition can not open the problem that sleeve pipe is annotated vapour, has avoided the thermal stress at packer card envelope place to concentrate the infringement that sleeve pipe is caused, and has avoided the generation of packer card well accident simultaneously.Simultaneously, thermal insulation tubing plays insulation effect in oil recovery process, promptly reduces wellbore heat loss, and the temperature drop to well head significantly reduces from the shaft bottom to make oil stream, only needs to replenish small amount of electrical energy and can keep required flowing temperature.Thereby, having reduced power consumption, power saving rate can reach more than 60%.

3. insert pump and thermal insulation tubing matching performance are reliable.Insert pump and the structurally reasonable supporting installation of thermal insulation tubing that the present invention adopts, be fit to condition under the super thickened oil steam-stimulated well, its structure is the fixed form of top fixture block grappling, the seat card firmly, seal adopts poly-PTFE, heatproof is above 300 ℃, solved insert pump for a long time the seat card and seal two technical barriers, further, because the reasonable installation of insert pump, make the present invention realize a bar notes vapour, advantages such as having not the easy damaged plunger is compared in fixed tubular column operation, insert pump of the present invention with tubing pump, insert pump is when the inspection pump in addition, only need remove rod string, need not to remove oil pipe (the present invention refers to thermal insulation tubing), therefore both can save the activity duration, save operating cost 40% again.

4. has the sand control function.The present invention has the sand washing nib under being incubated tubing string, has realized fixed tubular column sand washing operation, has sand control screen under the insert pump in addition, external diameter and insert pump coupling, it is not serious aboveground to shake out at some, avoids big sand grains to go into pump and causes the sand card, can satisfy the production needs of sand output well.

5. adopt the present invention owing to rising, descending tubing manipulation, the crude oil in the oil pipe can be leaked in the well again when playing insert pump simultaneously, reduced the well site pollution; Substantially avoided sand output well sand card tubing string to cause workover, the more effective sleeve pipe of having protected.

Fig. 1 is steam oil production flow chart figure in the prior art.

Fig. 2 is flow chart figure of the present invention.

Fig. 3 is an isolated plant structural representation of the present invention.

Below in conjunction with drawings and Examples the present invention is described in further detail.

Embodiment

As shown in Figure 2, method of work of the present invention is operated as follows: thermal insulation tubing 1), fill high pressure nitrogen in sleeve pipe and thermal insulation tubing toroidal cavity, and annotate vapour by the notes vapour amount of injection allocation, annotate vapour and finish back stewing well, open flow then; 2) sucker rod of band sand control screen and insert pump under, cable heating down in hollow rod is then recovered the oil; 3) oil recovery finishes a back sucker rod, annotates vapour, repeating step 2);

As shown in Figure 3, the inventive method isolated plant places 17 li of sleeve pipes, constitute variorum vapour by thermal insulation tubing and sucker rod and recover the oil insulation sand washing sand control in the integrated pipe column of one, wherein thermal insulation tubing 1 is inside and outside double-layer structure, establish insulation layer between two-layer and be used for filling with insulation material, described thermal insulation tubing 1 free end is installed together with sand washing nib 4 by rod-type pump seat envelopeshort circuit 2, is ring cavity betweensleeve pipe 17 and thermal insulation tubing 1; Described rod-type pump seat envelopeshort circuit 2 has the undergauge section, and the undergauge section is divided into a ring-shaped groove; Described rod string is thathollow rod 6 lower ends addsolid sucker rod 7,insert pump 3,sand control screen 5 structures, whereinhollow rod 6 links withsolid sucker rod 7 changes and connects,insert pump 3 is installed on thesolid sucker rod 7, form bypump barrel 12,plunger 14, embedded aconnection piece 18 inpump barrel 12 tops wherein,connector 18 are provided with the alternate open-work of distance; One fixture block, 10 tops are connected withsolid sucker rod 7 contacts byspring 9, the bottom is stuck on the alternate open-work of distance on theconnector 18,connector 18 upper ends are one with the seat envelope mandrel 8 that is set insolid sucker rod 7 outer walls, a standingvalve 15 is established inpump barrel 12 bottoms, thesand control screen 5 that free end is established plug is installed at 3 ends of insert pump, describedsand control screen 5 external diameters andinsert pump 3 couplings,plunger 14 lower ends are provided withtravelling valve 16; Present embodiment adopts Φ 57mm top grapplingformula insert pump 3; The sand washing nib 4 that 1 end of thermal insulation tubing is provided with can be realized fixed tubular column sand washing operation;

Describedconnector 18 and 2 of short circuits of rod-type pump seat envelope are provided with poly-PTFE sealingring sealing device 11, and heatproof reaches more than 300 ℃.

Method for thermal producing ultrathick oil by cyclic steam stimulation principle of the present invention is as follows:

When annotating vapour, all take annular space nitrogen-gas heat-insulating mode between thermal insulation tubing and the sleeve pipe, behind the notes vapour, directly lower sucker rod post oil pumping, oil recovery trips out rod string after producing end, if the shaft bottom sand setting, alternate water injection vapour is down then changeed in directly sand washing.Whole notes vapour-oil recovery-sand washing manufacturing process all adopts same tubing string, and during operation, tubing string is motionless, only rises, the operation of lower sucker rod post;

Wherein: when carrying on theplunger 14, because negative pressure, oil enters the cavity ofpump barrel 12 from the standingvalve 15 ofpump barrel 12 bottoms, this moment, the travelling valve ofplunger 14 cut out, and whenplunger 14 moved down, standingvalve 15 cut out,travelling valve 16 work, because the pressure of 12 li oil of pump barrel so oil enterstravelling valve 16 with in the epicoele, carries out oil-recovery operations greater thantravelling valve 16 upper cavity pressures.

The isolated plant course of work of the present invention is:

1. lower sucker rod post: refer to mounted rod string in advance (is comprised insert pump, sand control screen etc.) be lowered in the thermal insulation tubing, wherein specifically descend the pump step to be: to drawsolid sucker rod 7 upper ends, vertically sling, becausepump barrel 12 deadweights, make the top dead-centre ofpiston 14 to pump, at thismoment fixture block 10 lower ends are outwards squeezed in the centre that unfreezingjoint 13 entersfixture block 10 on the piston, its upper end is inwardly shunk, insertpump 3 inserts the down-hole in thermal insulation tubing 1, when arriving seat envelopeshort circuit 2 instantly, on the undergauge section of 8 present envelopeshort circuits 2 of seat envelope mandrel, at thismoment piston 14 continues descending inpump barrel 12, unfreezingjoint 13 breaks away fromfixture block 10 centers on the piston, under the effect ofspring 9, outwards eject the upper end offixture block 10, enters in the belt groove of seat envelopeshort circuit 2, the pump housing is blocked, be anchored on the thermal insulation tubing 1; Makepump barrel 12 to the operating position, plunger slides into theoperating position 14 times, recovers the oil then.

2. play rod string: upwards carry rod string pullingsolid sucker rod 7, when unfreezingjoint 13 entered the center offixture block 10 on the piston, fixture block moved outside 10 lower ends, and regain the upper end, break away from belt groove in the seat envelopeshort circuit 2 and unfreezing,insert pump 3 can propose seat envelope section to ground thereupon.

Claims (8)

1. method for thermal producing ultrathick oil by cyclic steam stimulation is characterized in that operating as follows:

(1) thermal insulation tubing under fills high pressure nitrogen in sleeve pipe and thermal insulation tubing toroidal cavity, annotates vapour by the notes vapour amount of injection allocation, annotates vapour and finishes back stewing well, open flow then;

(2) rod string of band sand control screen and insert pump under, cable heating down in hollow rod is then recovered the oil;

(3) oil recovery finishes a back rod string, annotates vapour, repeating step (2).

2. according to the described method for thermal producing ultrathick oil by cyclic steam stimulation of claim 1, it is characterized in that: have sand grains enter insert pump/pipeline need the cleaning situation under, in step (1) back, preceding the adding of step (2) do sand washing with described thermal insulation tubing and operate.

3. according to the described method for thermal producing ultrathick oil by cyclic steam stimulation of claim 1, it is characterized in that: need under the situation at the inspection pump, behind the oil recovery roofbolt, added the oil recovery roofbolt under step (2), the inspection pump descends oil recovery roofbolt operating procedure again.

4. isolated plant according to the described method for thermal producing ultrathick oil by cyclic steam stimulation of claim 1, place sleeve pipe (17) lining, it is characterized in that: constitute by thermal insulation tubing and rod string and focus vapour oil recovery insulation sand washing sand control in the integrated pipe column of one, wherein thermal insulation tubing (1) is inside and outside double-layer structure, establish insulation layer between two-layer and be used for filling with insulation material, described thermal insulation tubing (1) free end is installed together by rod-type pump seat envelope short circuit (2) and sand washing nib (4), is ring cavity between sleeve pipe (17) and the thermal insulation tubing (1); Described rod string is that hollow rod (6) lower end adds solid sucker rod (7), insert pump (3), sand control screen (5) structure, wherein hollow rod (6) links with solid sucker rod (7) change and connects, insert pump (3) is installed on the solid sucker rod (7) by seat envelope mandrel (8), one fixture block (10) top is connected with solid oil pick-up tube (7) contact by spring (9), the bottom is stuck on the alternate open-work of distance on the connector (18) of insert pump (3), install a free end and establish the sand control screen of plug (5) at insert pump (3) end, described sand control screen (5) external diameter and insert pump (3) coupling.

5. according to the described isolated plant of claim 4, it is characterized in that: described insert pump (3) is made up of pump barrel (12), plunger (14), and embedded a connection piece in pump barrel (12) top (18) wherein, connector (18) are provided with the alternate open-work of distance; Described fixture block (10) top is connected with solid sucker rod (7) contact by spring (9), the bottom is stuck on the open-work on the connector (18), connector (18) upper end is one with the seat envelope mandrel (8) that is set in solid sucker rod (7) outer wall, a standing valve (15) is established in pump barrel (12) bottom, and plunger (14) lower end is provided with travelling valve (16).

6. according to the described isolated plant of claim 4, it is characterized in that: described rod-type pump seat envelope short circuit (2) has the undergauge section, and the undergauge section is divided into a ring-shaped groove.

7. according to claim 4 or 5 described isolated plants, it is characterized in that: be provided with sealing device (11) between described connector (18) and rod-type pump seat envelope short circuit (2).

8. according to the described isolated plant of claim 7, it is characterized in that: described sealing device (11) is poly-PTFE sealing ring.

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