FR2600664A1 - Process for improving the physicochemical properties of polymer solutions employed in oil services - Google Patents
Process for improving the physicochemical properties of polymer solutions employed in oil services Download PDFInfo
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- FR2600664A1 FR2600664A1 FR8609502A FR8609502A FR2600664A1 FR 2600664 A1 FR2600664 A1 FR 2600664A1 FR 8609502 A FR8609502 A FR 8609502A FR 8609502 A FR8609502 A FR 8609502A FR 2600664 A1 FR2600664 A1 FR 2600664A1
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- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
- C09K8/00—Compositions for drilling of boreholes or wells; Compositions for treating boreholes or wells, e.g. for completion or for remedial operations
- C09K8/60—Compositions for stimulating production by acting on the underground formation
- C09K8/84—Compositions based on water or polar solvents
- C09K8/86—Compositions based on water or polar solvents containing organic compounds
- C09K8/88—Compositions based on water or polar solvents containing organic compounds macromolecular compounds
- C09K8/90—Compositions based on water or polar solvents containing organic compounds macromolecular compounds of natural origin, e.g. polysaccharides, cellulose
- C09K8/905—Biopolymers
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B24/00—Use of organic materials as active ingredients for mortars, concrete or artificial stone, e.g. plasticisers
- C04B24/24—Macromolecular compounds
- C04B24/38—Polysaccharides or derivatives thereof
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08B—POLYSACCHARIDES; DERIVATIVES THEREOF
- C08B37/00—Preparation of polysaccharides not provided for in groups C08B1/00 - C08B35/00; Derivatives thereof
- C08B37/0003—General processes for their isolation or fractionation, e.g. purification or extraction from biomass
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- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
- C09K8/00—Compositions for drilling of boreholes or wells; Compositions for treating boreholes or wells, e.g. for completion or for remedial operations
- C09K8/02—Well-drilling compositions
- C09K8/04—Aqueous well-drilling compositions
- C09K8/14—Clay-containing compositions
- C09K8/18—Clay-containing compositions characterised by the organic compounds
- C09K8/20—Natural organic compounds or derivatives thereof, e.g. polysaccharides or lignin derivatives
- C09K8/206—Derivatives of other natural products, e.g. cellulose, starch, sugars
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- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
- C09K8/00—Compositions for drilling of boreholes or wells; Compositions for treating boreholes or wells, e.g. for completion or for remedial operations
- C09K8/60—Compositions for stimulating production by acting on the underground formation
- C09K8/62—Compositions for forming crevices or fractures
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- Engineering & Computer Science (AREA)
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- Materials Engineering (AREA)
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- Chemical Kinetics & Catalysis (AREA)
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- Polymers & Plastics (AREA)
- Sustainable Development (AREA)
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- Dispersion Chemistry (AREA)
- General Health & Medical Sciences (AREA)
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Abstract
Description
Procédé pour améliorer les propriétés physico-chimiques de solutions de polymères utilisées dans les Services Pétroliers.Process to improve the physico-chemical properties of polymer solutions used in Petroleum Services.
L'invention concerne le secteur technique des services pétroliers et o lus particulièrement des fluides de complétion i de fracturation.The invention relates to the technical sector of petroleum services and o particularly read fluids i fracturing.
On sait que l'on utilise dans ce domaine des solutions de polymères et notamment des polysaccharides. Des exemples bien connus sont la gomme de guar, le xanthane, et leurs divers dérivés comme l'hydroxypropylguar (HPG).It is known that solutions of polymers and in particular polysaccharides are used in this field. Well-known examples are guar gum, xanthan, and their various derivatives such as hydroxypropylguar (HPG).
Ces solutions sont, en fonction de leur rôle, pompées au fond du puits sous de très fortes pressions et selon des techniques également bien connues. On adjoint en particulier des agents gélifiants, éventuellement à effet retard, pour obtenir à l'endroit d'application voulu une structure, non plus de solution, mais de gel plus ou moins reticulé. Lorsque de tels gels sont utilisés pour une opération de fracturation des roches du réservoir, on exige une excellente propriété "suspensoïde", c'est à dire la faculté pour le gel de retenir en dispersion (avec le moins possible de sédimentation) aussi stable que possible les particules de l'agent de soutènement (généralement de la bauxite ou du sable).On sait que cet agent a pour fonction de rester dans la fracture après la "casse" du gel et son évacuation, afin d'empecher la fracture de se refermer. I1 est donc essentiel que le gel "transporte" correctement l'agent de soutènement et le laisse en place à l'endroit prévu.These solutions are, depending on their role, pumped to the bottom of the well under very high pressures and according to techniques which are also well known. Gelling agents are added in particular, possibly with a delay effect, in order to obtain a structure, no longer of solution, but of more or less crosslinked gel, at the desired application site. When such gels are used for a fracturing operation of reservoir rocks, an excellent "suspensoid" property is required, that is to say the ability for the gel to retain in dispersion (with the least possible sedimentation) as stable as particles of the supporting agent (usually bauxite or sand) are possible. We know that this agent has the function of remaining in the fracture after the "breakage" of the gel and its evacuation, in order to prevent the fracture of to reclose. It is therefore essential that the gel "correctly" transports the propellant and leaves it in place at the intended location.
Il est également essentiel lorsque l'on "casse" le gel par un agent approprié ("breaker") que le gel ne laisse pas subsister de résidus qui colmatent et endommagent la formation.It is also essential when "breaking" the gel with an appropriate agent ("breaker") that the gel does not leave residues which clog and damage the formation.
Cependant, avec les polymères utilisés dans le secteur des services pétroliers, on rencontre très fréquemment des problèmes de sédimentation de l'agent de soutènement, et donc de mauvais placement de cet agent pouvant entraîner entre autres des problèmes de géométrie de fracture, ou encore d'endommagement du réservoir après la casse du gel. However, with the polymers used in the petroleum services sector, problems of sedimentation of the propellant are very frequently encountered, and therefore of improper placement of this agent which can lead, among other things, to problems of fracture geometry, or even damage to the tank after the gel breaks.
L'invention consiste à éliminer les microgels et les débris de la solution de polymère. La solution est bien entendu clarifiée, ce qui était prévisible. Par contre, on a remarqué que, de manière totalement surprenante, l'élimination des microgels et des débris provoque une remarquable amélioration des propriétés suspensoïdes et de transport de l'agent de soutènement, aussi bien en ce qui concerne la solution du polymère que le gel dont on provoque ultérieurement la formation.The invention is to remove microgels and debris from the polymer solution. The solution is of course clarified, which was to be expected. On the other hand, it has been observed that, completely surprisingly, the elimination of microgels and debris causes a remarkable improvement in the suspensoid and transport properties of the propellant, both with regard to the polymer solution and the gel which is subsequently caused to form.
Cette amélioration est constatée quel que soit le polymère utilisé'. Les autres propriétés de la solution de polymère et du gel, notamment les propriétés rhéologiques, ne sont pas affectées de façon sérieuse par l'élimination selon l'invention des microgels et débris.This improvement is noted whatever the polymer used. The other properties of the polymer solution and of the gel, in particular the rheological properties, are not seriously affected by the elimination according to the invention of microgels and debris.
L'art antérieur ne contient aucun indice permettant de relier la présence connue d'une très faible proportion de microgels et de débris dans la solution de polymère, notamment de xanthane à la propriété suspensoïde de cette solution et de son gel.The prior art contains no indication allowing the known presence of a very small proportion of microgels and debris in the polymer solution, in particular xanthan, to be linked to the suspensoid property of this solution and its gel.
I1 est également étonnant de constater que I'améliortion de plus de 150 % de la propriété suspensoïwe (cf exemples ci-après) obtenue selon l'inventi, ne s'accompagne pas d'une modification des propriétés rhéologiques dans le même sens et avec une intensité comparable. Au contraire, on verra ci-dessous que le plateau Newtonien des solutions traitees selon l'invention est abaissé d'environ 30 %. Ainsi, alors que l'on sait que propriété suspensoïde et propriétés rhéologiques sont liées, et que l'on s'attend donc à ce qu'elles évoluent dans le meme sens, le traitement selon l'invention les fait évoluer en sens inverse. It is also astonishing to note that the improvement of more than 150% of the suspensoïwe property (see examples below) obtained according to the invention, is not accompanied by a modification of the rheological properties in the same direction and with comparable intensity. On the contrary, it will be seen below that the Newtonian plateau of the solutions treated according to the invention is lowered by about 30%. Thus, while it is known that suspensoid property and rheological properties are linked, and that it is therefore expected that they evolve in the same direction, the treatment according to the invention makes them evolve in the opposite direction.
L'abaissement du plateau Newtonien pouvait à cet égard etre prévu comme conséquence de la filtration selon'l'invention. La conséquence logique de cet abaissement était un amoindrissement de la propriété suspensoïde. Or le traitement selon l'invention augmente cette propriété avec un facteur de plus de 1,5. Ceci est contraire aux enseignements antérieurs. The lowering of the Newtonian plate could in this respect be provided as a consequence of filtration according to the invention. The logical consequence of this lowering was a lessening of the suspensoid property. However, the treatment according to the invention increases this property with a factor of more than 1.5. This is contrary to previous teachings.
Le dispositif experimental qui a permis de mettre en évidence l'effet ci-dessus est représenté sur la
Figure 3 annexée.The experimental device which made it possible to highlight the above effect is represented on the
Figure 3 attached.
Les références ont les significations suivantes.The references have the following meanings.
Un tube de sédimentation (3) est balayé par l'émission d'une source (1) d'Am 241. La source est placée en regard d'un photodétecteur (2) et son émission traverse le tube (3) pour aller frapper le détecteur. La source et le détecteur sont placés sur un socle (6) qui peut être animé d'un mouvement vertical par tout moyen comme par exemple un moteur (4) et un système à vis (5).A sedimentation tube (3) is swept by the emission of a source (1) of Am 241. The source is placed opposite a photodetector (2) and its emission passes through the tube (3) to strike the detector. The source and the detector are placed on a base (6) which can be driven in a vertical movement by any means such as for example a motor (4) and a screw system (5).
On a utilisé pour les essais une solution de polymère à 0,55 % en poids dans l'eau distillée.A 0.55% by weight polymer solution in distilled water was used for testing.
On a observé la sédimentation dans le tube (3) de billes dispersées dans la solution.The sedimentation in the tube (3) of beads dispersed in the solution was observed.
La sédimentation est suivie de façon simple et reproductible par mesure de l'atténuation des rayons traversant le tube.The sedimentation is followed in a simple and reproducible manner by measuring the attenuation of the rays passing through the tube.
On a utilisé des billes consistant en microsphères de verre de diamètre 106-125/L, , en concentration de 10 t en poids/poids de la solution de polymère.Beads consisting of glass microspheres of diameter 106-125 / L, were used, in a concentration of 10 t w / w of the polymer solution.
On a effectué selon l'invention une centrifugation à 20.000 g durant 2 heures, sur des solutions de polymère dont la viscosité était de 0,5 Pa.s.A centrifugation was carried out according to the invention at 20,000 g for 2 hours, on polymer solutions whose viscosity was 0.5 Pa.s.
On a utilisé des filtres de diamètre de pores suffisamment important pour ne pas etre trop voisin de la longueur de chaîne du polymère (1,2 + pour la gomme de guar hydroxyprop ylée ou HPG).Filters of sufficiently large pore diameter were used so as not to be too close to the length of the polymer chain (1.2 + for hydroxypropylated guar gum or HPG).
On a comparé la solution initiale et la solkution ayant subi la centrifugation en termes de turbidité et de résidus solides après la casse du gel (casse provoquée par un agent oxydant, comme le persulfate d'ammonium, de manière connue en soi. The initial solution and the centrifuged solkution were compared in terms of turbidity and solid residue after breakage of the gel (breakage caused by an oxidizing agent, such as ammonium persulfate), in a manner known per se.
Les résultats sont rassemblés dans le tableau ci-dessous (HPG)
Eau Solution Solution
pure initiale centrifugée
Turbidité (mV) 1000 766 998
Résidus solides après casse 0 7 < 0,1 (% en poids)
La turbidité est mesurée par l'intensité de la lumière traversant un volume standard de solution et détectée par un phototrode. Celui-ci produit un courant d'intensité (ou de voltage) inversement proportionnel à la turbidité.The results are collated in the table below (HPG)
Water Solution Solution
pure centrifuged initial
Turbidity (mV) 1000 766 998
Solid residue after breakage 0 7 <0.1 (% by weight)
Turbidity is measured by the intensity of light passing through a standard volume of solution and detected by a phototrode. This produces a current of intensity (or voltage) inversely proportional to the turbidity.
On a egalement étudié; dans une seconde série d'essais, les profils de sédimentation des billes de verre décrites ci-dessus selon que la solution de polymère avait été, préalablement à la dispersion des billez centrifugée ou non.We also studied; in a second series of tests, the sedimentation profiles of the glass beads described above according to whether the polymer solution had been, prior to the dispersion of the bills, centrifuged or not.
On a utiles l'appareil représenté sur la Fig.3. La viscosit < est de 0,42 Pa.s. Le profil est étudié après 2000 s, et représenté sur la Fig.l, pour la solution non traitée, ou bien après 3600 s pour la solution préalablement traitée (Fig. 2).We used the device shown in Fig. 3. The viscosity <is 0.42 Pa.s. The profile is studied after 2000 s, and shown in Fig.l, for the untreated solution, or after 3600 s for the previously treated solution (Fig. 2).
On déduit de la comparaison des Fig. 1 et 2 que la vitesse de sédimentation est 1,8 fois inférieure dans le cas de la solution préalablement filtrée.We deduce from the comparison of Figs. 1 and 2 that the sedimentation rate is 1.8 times lower in the case of the previously filtered solution.
Ceci signifie que l'aptitude de la solution de polymère et du gel à garder l'agent de soutènement en suspension est considérablement améliorée. En d'autres termes, l'agent de soutènement sera placé dans la fracture de manière homogène, et en particulier sur toute la hauteur de la fracture.This means that the ability of the polymer solution and the gel to keep the propellant in suspension is considerably improved. In other words, the support agent will be placed in the fracture in a homogeneous manner, and in particular over the entire height of the fracture.
Ceci est capital pour le succès de l'opération de fracturation. This is crucial for the success of the fracturing operation.
En effet, si l'agent de soutènement a tendance à sédimenter, il va se trouver surtout dans la partie intérieure de la fracture (on rappellera que la fracture est sensiblement verticale et s'étend radialement autour du puits) et, au moment de la casse du gel, toute la partie supérieure de la fracture va se refermer sous la pression des roches.Indeed, if the support agent tends to sediment, it will be found especially in the interior part of the fracture (it will be recalled that the fracture is substantially vertical and extends radially around the well) and, at the time of the break the gel, the whole upper part of the fracture will close under the pressure of the rocks.
L'efficacité de la fracturation serait ainsi réduite, par exemple, de moitié.The efficiency of fracturing would be reduced, for example, by half.
D'autres séries d'essais ont également été effectués sur la gomme xanthane, en utilisant le meme dispositif expérimental et le meme mode opératoire général que ci-dessus. Les résultats sont présentés sur les figures 4, 5 et 6 annexées.Other series of tests were also carried out on xanthan gum, using the same experimental device and the same general procedure as above. The results are presented in Figures 4, 5 and 6 attached.
La figure 4 confirme que le traitement d'ultracentrifugation n'a pas d'influence néfaste sur la rhéologie, et ce en particulier pour les forts taux de cisaillement qui correspondent aux conditions normales d'opérations.FIG. 4 confirms that the ultracentrifugation treatment has no harmful influence on the rheology, and this in particular for the high shear rates which correspond to normal operating conditions.
La Fig. 5 représente la concentration sur la hauteur de la colonne d'essai et l'on voit que, tandis que cette concentration varie régulièrement avec le xanthanne normal, elle reste sensiblement instante sur toute la hauteur de la colonne avec la solution de xanthane centrifugée. Dans le premier cas, on a une sédimentation rapide, que l'on n'observe pas dans le second cas.Fig. 5 represents the concentration over the height of the test column and it can be seen that, while this concentration varies regularly with normal xanthan, it remains substantially instantaneous over the entire height of the column with the centrifuged xanthan solution. In the first case, there is rapid sedimentation, which is not observed in the second case.
La Fig. 6 est comparable à la Fig. 5.Fig. 6 is comparable to FIG. 5.
On a fait coïncider les deux courbes par chargement du temps après lequel on effectue l'observation. La coïncidence se produit lorsque l'on observe la colonne de gomme non traitée après 1500 s et celle de gomme traitée après 6 450 s : on en deduit donc que la sédimentation est environ 4 fois plus rapide lorsque la gomme n'a pas subi le traitement selon l'invention. The two curves were made to coincide by loading the time after which the observation is made. The coincidence occurs when we observe the column of untreated gum after 1500 s and that of treated gum after 6 450 s: we therefore deduce that the sedimentation is about 4 times faster when the gum has not undergone treatment according to the invention.
Claims (4)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FR8609502A FR2600664B1 (en) | 1986-06-27 | 1986-06-27 | PROCESS FOR IMPROVING THE PHYSICO-CHEMICAL PROPERTIES OF POLYMER SOLUTIONS USED IN OIL SERVICES |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FR8609502A FR2600664B1 (en) | 1986-06-27 | 1986-06-27 | PROCESS FOR IMPROVING THE PHYSICO-CHEMICAL PROPERTIES OF POLYMER SOLUTIONS USED IN OIL SERVICES |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| FR2600664A1 true FR2600664A1 (en) | 1987-12-31 |
| FR2600664B1 FR2600664B1 (en) | 1988-09-23 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| FR8609502A Expired FR2600664B1 (en) | 1986-06-27 | 1986-06-27 | PROCESS FOR IMPROVING THE PHYSICO-CHEMICAL PROPERTIES OF POLYMER SOLUTIONS USED IN OIL SERVICES |
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| Country | Link |
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| FR (1) | FR2600664B1 (en) |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2001376A (en) * | 1977-07-25 | 1979-01-31 | Rhone Poulenc Ind | Assisted oil recovery with use of fermentation fluids |
| FR2440992A1 (en) * | 1978-11-06 | 1980-06-06 | Pfizer | PROCESS FOR THE TREATMENT OF A XANTHOMONAS FERMENTATION BROTH FOR ITS USE IN THE DISPLACEMENT OF OIL FROM PARTIALLY EXHAUSTED DEPOSITS |
| US4256590A (en) * | 1977-05-09 | 1981-03-17 | Exxon Research & Engineering Co. | Modified heteropolysaccharides and their preparation |
| US4337157A (en) * | 1978-03-17 | 1982-06-29 | Manville Service Corporation | Biopolymer filtration process |
| US4442897A (en) * | 1980-05-23 | 1984-04-17 | Standard Oil Company | Formation fracturing method |
-
1986
- 1986-06-27 FR FR8609502A patent/FR2600664B1/en not_active Expired
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4256590A (en) * | 1977-05-09 | 1981-03-17 | Exxon Research & Engineering Co. | Modified heteropolysaccharides and their preparation |
| GB2001376A (en) * | 1977-07-25 | 1979-01-31 | Rhone Poulenc Ind | Assisted oil recovery with use of fermentation fluids |
| US4337157A (en) * | 1978-03-17 | 1982-06-29 | Manville Service Corporation | Biopolymer filtration process |
| FR2440992A1 (en) * | 1978-11-06 | 1980-06-06 | Pfizer | PROCESS FOR THE TREATMENT OF A XANTHOMONAS FERMENTATION BROTH FOR ITS USE IN THE DISPLACEMENT OF OIL FROM PARTIALLY EXHAUSTED DEPOSITS |
| US4442897A (en) * | 1980-05-23 | 1984-04-17 | Standard Oil Company | Formation fracturing method |
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| Publication number | Publication date |
|---|---|
| FR2600664B1 (en) | 1988-09-23 |
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