ПАТЕНТНЫЙ ПОИСК В РФ
НОВЫЕ ПАТЕНТЫ, ЗАЯВКИ НА ПАТЕНТ
БИБЛИОТЕКА ПАТЕНТОВ НА ИЗОБРЕТЕНИЯ

Use of encapsulated chemical during fracturing

Патентный поиск по классам МПК-8:

Класс E21B43/26 формированием трещин или разрывов 

Патенты РФ в классе E21B43/26:
способ разработки низкопроницаемой нефтяной залежи горизонтальными скважинами на естественном режиме -  патент 2528757
способ разработки нефтяной залежи горизонтальными скважинами с проведением многократного гидравлического разрыва пласта -  патент 2528309
способ разработки нефтяной залежи с проведением гидроразрыва пласта -  патент 2528308
улучшенные способы размещения и отклонения текучих сред в подземных пластах -  патент 2527988
способ интенсификации работы скважины -  патент 2527913
жидкости для технического обслуживания ствола скважины, содержащие катионные полимеры, и способы их применения -  патент 2527102
способ разработки низкопроницаемой нефтяной залежи -  патент 2526937
способ разработки низкопроницаемой нефтяной залежи горизонтальными скважинами с поддержанием пластового давления -  патент 2526430
способ направленного гидроразрыва массива горных пород -  патент 2522677
способ разработки неоднородной нефтяной залежи -  патент 2517674

Класс E21B43/16 способы усиленной добычи для получения углеводородов


Классы МПК:E21B43/26 формированием трещин или разрывов 
E21B43/16 способы усиленной добычи для получения углеводородов
Автор(ы): Cochet, Thomas (Paris, FR)
Hughes, Trevor (Cambridge, GB)
Kefi, Slaheddine (Velizy Villacoublay, FR)
Lafitte, Valerie (Cambridge, GB)
Tan, Khooi (Coton, GB)
Tustin, Gary (Sawston, GB)
Wang, Shiyi (Cambridge, GB)
Патентообладатель(и): Schlumberger Technology Corporation (Sugar Land, TX, US)
Приоритеты:
подача заявки
03.06.2009
публикация патента
12.03.2013

РЕФЕРАТ (Abstract)

A process for hydraulic fracturing of a subterranean reservoir formation penetrated by a wellbore includes pumping a fracturing fluid or other aqueous fluid from the surface via the wellbore and into the reservoir. This fluid is an aqueous suspension of particles which each comprise an oilfield chemical distributed within an encapsulating matrix of water-insoluble carrier material. The encapsulating matrix is chosen so as to provide a delayed release of the oilfield chemical from the particles into surrounding fluid, such that oilfield chemical is liberated from the particles after they have entered the fracture. The encapsulating matrix may be a polymer which is at least partially amorphous, with a glass transition temperature below the reservoir temperature.
Полный текст Патента US 8393395 + PDF


ФОРМУЛА ИЗОБРЕТЕНИЯ (CLAIMS)

The invention claimed is:

1. A process for hydraulic fracturing of a subterranean reservoir formation penetrated by a wellbore, comprising preparing an emulsion with an aqueous continuous phase and a disperse phase which comprises an oilfield chemical and a solution of a water-insoluble carrier matrix material in an organic solvent, evaporating the organic solvent while agitating the emulsion, forming particles which each comprise an oilfield chemical distributed as multiple particles enclosed within a particle of a water-insoluble carrier matrix material, pumping an aqueous suspension of the particles of the carrier matrix material-from the surface via the wellbore and into the reservoir, wherein the carrier matrix material is an organic polymer which has a Tg above 40° C. but below the temperature of the reservoir so as to provide a delayed release of the oilfield chemical from the particles into surrounding fluid through increase in permeability of the matrix upon temperature rise within the reservoir to a temperature above Tg of the matrix, such that the oilfield chemical is liberated from the particles after they have entered the fracture.

2. The process of claim 1 wherein the aqueous suspension of particles is a suspension of the particles in a hydraulic fracturing fluid pumped into the wellbore at sufficient pressure to fracture the formation.

3. The process of claim 2 wherein the fracturing fluid comprises an aqueous dispersion of a thickener.

4. The process of claim 2 wherein the fracturing fluid comprises an aqueous dispersion of a thickener which forms a filtercake on surfaces of the formation exposed to the fracture and the oilfield chemical is a breaker, effective to degrade the thickener in the filtercake.

5. The process of claim 4 wherein the thickener comprises a polysaccharide and the breaker is a peroxide.

6. The process of claim 4 wherein the thickener comprises a polysaccharide and the breaker is an enzyme.

7. The process of claim 4 wherein the thickener in the fracturing fluid comprises a viscoelastic surfactant and the breaker is a compound comprising a hydrophobic chain of at least 12 carbon atoms.

8. The process of claim l wherein the organic polymer has a Tg in a range from 40° C. to 175° C.

9. The process of claim 1 wherein the organic polymer is a polymer of a hydroxycarboxylic acid.

10. The process of claim 1 wherein the organic polymer comprises a mixture of polymers.

11. The process of claim 1 wherein at least 75% of the oilfield chemical is retained within the particles of the carrier matrix material until after they enter the fracture.

12. The process of claim 1 wherein at least 50% of the oilfield chemical is liberated into the fracture before the production of hydrocarbon via the fracture.

13. The process of claim 1 wherein at least 95% of the oilfield chemical is liberated into the fracture within 5 days.

14. The process of claim 1 wherein at least 50% of the chemical is retained by the particles of the carrier matrix material for a period of at least 5 days at the temperature of the reservoir and subsequently released.

15. The process of claim 1 wherein the particles of the carrier matrix material have a median particle size of at least 15 micron.

16. The process of claim 1 wherein the particles of the carrier matrix material have a median particle size in a range from 25 to 200 micron.

17. The process of claim 1 comprising a step of pumping a suspension of proppant into the fracture before or concurrently with said particles of the carrier matrix material wherein said particles of the carrier matrix material have a median particle size in a range from 25 to 200 micron.

18. The process of claim 1 comprising a step of pumping a suspension of proppant into the fracture concurrently with said particles of the carrier matrix material wherein said particles have a median particle size of at least 250 micron.

19. The process of claim 1 wherein the particles of the carrier matrix material are elongate fibers.

20. The process of claim 1 wherein the oilfield chemical is a tracer and the process includes a subsequent step of analyzing fluid flowing out of the reservoir via the wellbore to detect the presence or absence of the tracer therein.

21. The process of claim 1 which comprises pumping hydraulic fracturing fluid from the surface via the wellbore and into the reservoir so as to open fractures of the reservoir formation at multiple locations along the length of a wellbore, and comprising pumping said aqueous suspension of particles into each fracture.

22. The process of claim 1 wherein the oilfield chemical has a molecular weight no greater than 1000.

23. The process of claim 1 wherein at least 75% of the oilfield chemical is retained within the particles until after they enter the fracture and at least 50% of the oilfield chemical is liberated into the fracture before the production of hydrocarbon via the fracture.

24. A process for hydraulic fracturing of a subterranean reservoir formation penetrated by a wellbore, comprising preparing an emulsion with an aqueous continuous phase and a disperse phase which comprises an oilfield chemical and a solution of a water-insoluble carrier matrix material in an organic solvent, evaporating the organic solvent while agitating the emulsion, forming particles which each comprise an oilfield chemical distributed as multiple particles enclosed within a particle of a water-insoluble carrier matrix material, pumping an aqueous suspension of the particles of the carrier matrix material from the surface via the wellbore and into the reservoir, wherein the particles of the carrier matrix material have a median particle size in a range from 25 to 200 micron and the carrier matrix material is chosen so as to provide a delayed release of the oilfield chemical from the particles into surrounding fluid through chemical degradation of the matrix within the reservoir such that the oilfield chemical is liberated from the particles after they have entered the fracture.

25. The process of claim 24 wherein the carrier matrix material comprises a polymer of a hydroxycarboxylic acid.

26. A process for hydraulic fracturing of a subterranean reservoir formation penetrated by a wellbore, comprising preparing an emulsion with an aqueous continuous phase and a disperse phase which comprises an oilfield chemical and a solution of a water-insoluble carrier matrix material in an organic solvent, evaporating the organic solvent while agitating the emulsion, forming particles which each comprise an oilfield chemical distributed as multiple particles enclosed within a particle of a water-insoluble carrier matrix material, pumping a hydraulic fracturing fluid which comprises an aqueous dispersion of a thickener from the surface via the wellbore and into the reservoir at sufficient pressure to fracture the formation, the hydraulic fracturing fluid containing suspended particles of the carrier matrix material. wherein the particles of carrier matrix material have a median particle size in a range from 25 to 200 micron, the oilfield chemical therein is a breaker, effective to degrade the thickener, and the carrier matrix material is an organic polymer which has a Tg above 40° C. but below the temperature of the reservoir so as to provide a delayed release of the breaker from the particles into surrounding fluid through increase in permeability of the matrix upon temperature rise within the reservoir to a temperature above Tg of the matrix, such that the breaker is liberated from the particles at a rate which increases with temperature after they have entered the fracture.


Предыдущий   патент US   Следующий

Наверх