This disclosure relates to a composition and method to improve the recovery of hydrocarbons from a fractured formation. More specifically, this disclosure relates to a composition and method to reduce the viscosity of a fracturing fluid.
Hydraulic fracturing fluids containing proppants are used extensively to enhance productivity from hydrocarbon reservoir formations, including carbonate and sandstone formations. During hydraulic fracturing operations, a fracturing treatment fluid is pumped under a pressure and rate sufficient for cracking the formation of the reservoir and creating a fracture. Fracturing operations usually consist of three main stages including a pad fluid stage, a proppant fluid stage, and an overflush fluid stage. The pad fluid stage typically consists of pumping a pad fluid into the formation. The pad fluid is a viscous gelled fluid which initiates and propagates the fractures. Auxiliary fractures can propagate from the fractures to create fracture networks. A fracture network can comprise fractures and auxiliary fractures. Auxiliary fractures can connect the fractures.
The proppant fluid stage involves pumping a proppant fluid into the fractures of the formation. The proppant fluid contains proppants mixed with a viscous gelled fluid or a visco-elastic surfactant fluid. The proppants in the proppant fluid are lodged in the fractures and create conductive fractures through which hydrocarbons flow. The final stage, the overflush stage, includes pumping a viscous, gelled fluid into the fractures to ensure the proppant fluid is pushed inside the fractures. While the three stages have different aims, all three make use of highly viscous and/or gelled fluids to achieve those aims.
A downside of the traditional method is that a high volume of gelled or polymeric materials can be left behind in the fractures. The gelled materials can be concentrated around the proppant in the fractures or can be freely in the fractures. The gelled material acts to block the fractures reducing the fracture conductivity. The hydrocarbons which flow from the reservoir formation are unable to move the gelled materials. Traditional methods for cleaning the fractures involve viscosity breakers or other elements to breakdown the fluid. These traditional methods suffer from an inability to completely cleanup the fractures, leaving residual viscous material and reduced conductivity.
This disclosure relates to a composition and method to improve the recovery of hydrocarbons from a fractured formation. More specifically, this disclosure relates to a composition and method to reduce the viscosity of a fracturing fluid, such as, for example, a gelled and/or viscous fracturing fluid.
In one aspect, a method for improved hydrocarbon recovery from a formation due to cleanup of a residual viscous material is provided. The method includes the step of fracturing the formation with a fracturing fluid to generate fractures. The fracturing fluid includes a viscous fluid component, the viscous fluid component operable to fracture the formation to create fractures leaving behind the residual viscous material in the fractures, the viscous fluid component having a viscosity, a proppant component, the proppant component includes a proppant, the proppant operable to hold open the fractures, wherein the proppant component is carried to the fractures by the viscous fluid component, and a cleanup fluid.
The cleanup fluid includes an acid precursor, the acid precursor operable to trigger an exothermic reaction component, and the exothermic reaction component operable to generate heat, wherein the heat is operable to reduce a viscosity of the residual viscous material to create a reduced viscosity material, the reduced viscosity material operable to flow from the formation. Fractures can include auxiliary fractures, which propagate from the fractures.
In certain aspects, the exothermic reaction component includes an ammonium containing compound and a nitrite containing compound. In certain aspects of the present disclosure, the ammonium containing compound is NH4Cl and the nitrite containing compound is NaNO2. In certain aspects of the disclosure, the acid precursor is triacetin.
In a second aspect of the present disclosure, a cleanup fluid for reducing a viscosity of a residual viscous material in fractures is provided. The cleanup fluid includes an acid precursor, the acid precursor operable to trigger an exothermic reaction component, and the exothermic reaction component operable to generate heat, wherein the heat is operable to reduce a viscosity of the residual viscous material to create a reduced viscosity material, the reduced viscosity material operable to flow from the fractures.
In certain aspects, the exothermic reaction component includes an ammonium containing compound and a nitrite containing compound. In certain aspects of the present disclosure, the ammonium containing compound is NH4Cl and the nitrite containing compound is NaNO2. In certain aspects of the present disclosure, the acid precursor is triacetin.
In a third aspect, a method to cleanup fractures post hydraulic fracturing is provided. The method includes the steps of fracturing a formation in a hydraulic fracturing operation to produce fractures, and injecting a cleanup fluid into the fractures to reduce a viscosity of a residual viscous material.
In certain aspects of the present disclosure, the step of fracturing the formation includes the step of fracturing the formation with a fracturing fluid to generate fractures. The fracturing fluid includes a viscous fluid component, the viscous fluid component operable to fracture the formation to create fractures leaving behind the residual viscous material in the fractures, the viscous fluid component having a viscosity, and a proppant component, the proppant component comprising a proppant, the proppant operable to hold open the fractures, wherein the proppant component is carried to the fractures by the viscous fluid component. In certain aspects of the present disclosure, the cleanup fluid includes an acid precursor, the acid precursor operable to trigger an exothermic reaction component, and the exothermic reaction component operable to generate heat, wherein the heat is operable to reduce a viscosity of the residual viscous material to create a reduced viscosity material, the reduced viscosity material operable to flow from the fractures. In certain aspects of the present disclosure, the exothermic reaction component includes an ammonium containing compound and a nitrite containing compound. In certain aspects, the ammonium containing compound is NH4Cl and the nitrite containing compound is NaNO2. In certain aspects, the acid precursor is triacetin.
These and other features, aspects, and advantages of the present disclosure will become better understood with regard to the following descriptions, claims, and accompanying drawings. It is to be noted, however, that the drawings illustrate only several embodiments of the disclosure and are therefore not to be considered limiting of the disclosure's scope as it can admit to other equally effective embodiments.
While the disclosure will be described with several embodiments, it is understood that one of ordinary skill in the relevant art will appreciate that many examples, variations and alterations to the apparatus and methods described herein are within the scope and spirit of the disclosure. Accordingly, the embodiments described herein are set forth without any loss of generality, and without imposing limitations, on the claims.
In one aspect, a method for improved hydrocarbon recovery from a formation due to cleanup of a residual viscous material is provided. The hydraulic fracturing operation fractures the formation using fracturing fluid to create fractures. Formations include sandstone and carbonate, for example.
The fracturing fluid includes a viscous fluid component and a proppant component. The viscous fluid component has a viscosity. The viscous fluid component is operable to increase the viscosity of the fracturing fluid. Viscous fluid components include viscosified water-based fluids, non-viscosified water-based fluids, gel-based fluids, gel oil-based fluids, acid-based fluids, and foam fluids. Gel-based fluids include cellulose derivatives and guar-based fluids. Cellulose derivatives include carboxymethyl cellulose, hydroxyethyl cellulose, carboxymethyl hydroxyethyl cellulose, hydroxypropyl cellulose, and methyl hydroxyl ethyl cellulose.
Guar-based fluids include hydroxypropyl guar, carboxymethyl guar, guar cross-linked boron ions from an aqueous borax/boric acid solution, and guar cross-linked with organometallic compounds. Organometallic compounds include zirconium, chromium, antimony, and titanium salts. Gel oil-based fluids include aluminum phosphate-ester oil gels. In at least one embodiment of the present disclosure, the viscous fluid component is an aqueous guar solution, having a concentration of guar gum between about 0.1% and about 15%, between about 0.1% and about 10%, between about 1% and about 10%, between about 2% and about 8%, and between about 4% and about 6%.
The proppant component includes a proppant. The proppant is operable to hold open fractures created by the viscous fluid component. Any proppants capable of holding open fractures to create a conductive fractures are suitable for use in the present disclosure. In some embodiments, the proppant component includes a viscous carrier fluid having a viscosity.
Viscous carrier fluids include viscosified water-based fluids, non-viscosified water-based fluids, gel-based fluids, gel oil-based fluids, acid-based fluids, and foam fluids. Gel-based fluids include cellulose derivatives and guar-based fluids. Cellulose derivatives include carboxymethyl cellulose, hydroxyethyl cellulose, carboxymethyl hydroxyethyl cellulose, hydroxypropyl cellulose, and methyl hydroxyl ethyl cellulose.
Guar-based fluids include hydroxypropyl guar, carboxymethyl guar, guar cross-linked boron ions from an aqueous borax/boric acid solution, and guar cross-linked with organometallic compounds. Organometallic compounds include zirconium, chromium, antimony, and titanium salts. Gel oil-based fluids include aluminum phosphate-ester oil gels. In some embodiments, the hydraulic fracturing operation uses a one stage fracturing fluid, in which the fracturing fluid includes both the viscous fluid component and the proppant component, in which the viscous fluid component carries the proppant component to the fractures.
In at least one embodiment, the hydraulic fracturing operation uses a multi-stage fracturing fluid in which the viscous fluid component is injected into the formation, followed by the proppant component in the viscous carrier fluid. In some embodiments, the injection of the proppant component is followed by injection of additional viscous fluids to ensure the proppants are placed in the fractures. The additional viscous fluids have a viscosity.
In some embodiments, the viscosity of the viscous fluid component, the viscous carrier fluid, and additional viscous fluids are the same. In some embodiments, the viscosity of the viscous fluid component, the viscous carrier fluid, and additional viscous fluids are different. The injection of the fracturing fluid ceases after the proppants are placed in the fractures and the fracturing fluid is allowed to seep from the fractures. In some embodiments, the injection of the hydraulic fracturing fluid including the viscous fluid component and/or the proppant component and/or the overflush component and/or the exothermic reaction component does not generate foam or introduce foam into the hydraulic formation including the hydraulic fractures.
The hydraulic fracturing operation can leave residual viscous material in the fractures of a hydraulic formation. Residual viscous materials can include carboxymethyl cellulose, hydroxyethyl cellulose, carboxymethyl hydroxyethyl cellulose, hydroxypropyl cellulose, methyl hydroxyl ethyl cellulose, guar gum, hydroxypropyl guar, carboxymethyl guar, guar cross-linked with boron, aluminum phosphate-ester oil gel, and guar cross-linked with organometallic compounds. Organometallic compounds include zirconium, chromium, antimony, and titanium salts. In some embodiments of the present disclosure, the residual viscous material is a gelled material. In some embodiments of the present disclosure, the residual viscous material is a polymeric material. In at least one embodiment of the present disclosure, the residual viscous material is guar gum. The residual viscous material has a viscosity greater than the fracturing fluid. In at least one embodiment of the present disclosure, the residual viscous material is surrounding and/or adjacent to the proppants placed in the fractures.
The cleanup fluid acts, after the proppants have been placed in the fractures, to remove the residual viscous material. In one embodiment, the cleanup fluid is mixed with the fracturing fluid. In at least one embodiment of the present disclosure, where a multi-stage fracturing fluid is used, the cleanup fluid is a component of the fluids used at each stage of the hydraulic fracturing operation. In an alternate embodiment, the cleanup fluid is added only to the fluid of the final stage of the hydraulic fracturing operation, such as, for example, the overflush stage. In some embodiments, the cleanup fluid is pumped to the fractured formation as a separate step following the hydraulic fracturing operation.
In some embodiments, the cleanup fluid includes an acid precursor and an exothermic reaction component. The reaction of the exothermic reaction component results in a release of kinetic energy and thermal energy. The reaction of the exothermic reaction component generates heat and increases the pressure. The generated heat increases the temperature of the surrounding fluids, including fracturing fluid remaining in the fractures and residual viscous material. The increase in temperature reduces the viscosity of the fracturing fluid. The increase in temperature reduces the viscosity of the residual viscous material left in the fractures to create a reduced viscosity material. The reduced viscosity material flows from the fractures of the formation to the wellbore. The increase in pressure provides lift energy to push the reduced viscosity materials through the wellbore toward the surface. The removal of the residual viscous material increases the conductivity of the fractures. Increased conductivity of the fractures increases seepage of the fracturing fluid, improves fracturing efficiency, minimizes need for additional fracturing jobs, minimizes time between fracturing and well production, and increases hydrocarbon flow, which translates to increased hydrocarbon recovery.
The acid precursor is any acid that releases hydrogen ions to trigger the reaction of the exothermic reaction component. Acid precursors include triacetin (1,2,3-triacetoxypropane), methyl acetate, HCl, and acetic acid. In at least one embodiment, the acid precursor is triacetin. In at least one embodiment, the acid precursor is acetic acid.
The exothermic reaction component includes one or more redox reactants that exothermically react to produce heat and increase pressure. Exothermic reaction components include urea, sodium hypochlorite, ammonium containing compounds, and nitrite containing compounds. In at least one embodiment of the present disclosure, the exothermic reaction component includes ammonium containing compounds. Ammonium containing compounds include ammonium chloride, ammonium bromide, ammonium nitrate, ammonium sulfate, ammonium carbonate, and ammonium hydroxide.
In at least one embodiment, the exothermic reaction component includes nitrite containing compounds. Nitrite containing compounds include sodium nitrite and potassium nitrite. In at least one embodiment, the exothermic reaction component includes both ammonium containing compounds and nitrite containing compounds. In at least one embodiment, the ammonium containing compound is ammonium chloride, NH4Cl. In at least one embodiment, the nitrite containing compound is sodium nitrite, NaNO2.
In at least one embodiment of the present disclosure, the exothermic reaction component includes two redox reactants: NH4Cl and NaNO2, which react according to the following:
In a reaction of the exothermic reaction components according to the above equation, generated gas and heat contribute to the reduction of the viscosity of the residual viscous material.
The exothermic reaction component is triggered to react. In at least one embodiment of the present disclosure, the exothermic reaction component is triggered within the fractures. In at least one embodiment of the present disclosure, the acid precursor triggers the exothermic reaction component to react by releasing hydrogen ions.
In at least one embodiment, the exothermic reaction component is triggered by heat. The wellbore temperature is reduced during a pre-pad injection or a pre-flush with brine and reaches a temperature below 120° F. (48.9° C.). The fracturing fluid of the present disclosure is then injected into the well and the wellbore temperature increases. When the wellbore temperatures reaches a temperature greater than or equal to 120° F., the reaction of the redox reactants is triggered. In at least one embodiment, the reaction of the redox reactants is triggered by temperature in the absence of the acid precursor. In at least one embodiment, the exothermic reaction component is triggered by heat when the exothermic reaction component is within the fractures.
In at least one embodiment, the exothermic reaction component is triggered by pH. A base is added to the fracturing fluid of the present disclosure to adjust the pH to between 9 and 12. In at least one embodiment, the base is potassium hydroxide. The fracturing fluid with the base is injected into the formation. Following the injection of the fracturing fluid, an acid is injected to adjust the pH to below 6. When the pH is below 6, the reaction of the redox reactants is triggered. In at least one embodiment, the exothermic reaction component is triggered by pH when the exothermic reaction component is within the fractures.
In at least one embodiment of the present disclosure, the cleanup fluid is introduced to the fractures following the hydraulic fracturing operation. Dual-string coiled tubing is used to introduce the exothermic reaction component and the acid precursor to the wellbore. In at least one embodiment, the exothermic reaction component includes NH4Cl and NaNO2. The acid precursor is acetic acid. The acetic acid is mixed with NH4Cl and injected in parallel with the NaNO2, using different sides of the dual-string coiled tubing. The exothermic reaction component and the acid precursor mix within the fractures.
An exothermic reaction component of a cleanup fluid consisting of 3M NH4Cl and 3M NaNO2 was added to a solution of 1% by volume guar at room temperature, see
A solution of an exothermic reaction component was prepared from 3M NH4Cl and 3M NaNO2. The solution was placed in an autoclave reactor at room temperature and an initial pressure of 1,000 psi. The reactor temperature was increased. The reaction was triggered at about 120° F., see
The exothermic reaction component showed compatibility with the viscous fluid component (here an x-linked gel). The fracturing fluid with the viscous fluid component, the exothermic reaction component, and the proppant component was also prepared and showed compatibility. The fracturing fluid, without the proppant component, was activated in the autoclave reactor by heating to the wellbore temperature to trigger the reaction of the exothermic reaction component. The heat generated by the reaction reduced the viscosity of the viscous fluid component to produce a reduced viscosity material, without injecting the viscosity breaker. Using a chandler viscometer, the viscosity of the fracturing fluid, containing the viscous fluid component and the exothermic reaction component, was measured pre-reaction and post-reaction. The viscosity of the fracturing fluid was reduced from 1600 cp to 10 cp, as shown in
Although the present disclosure has been described in detail, it should be understood that various changes, substitutions, and alterations can be made hereupon without departing from the principle and scope of the disclosure. Accordingly, the scope of the present disclosure should be determined by the following claims and their appropriate legal equivalents.
The singular forms “a,” “an,” and “the” include plural referents, unless the context clearly dictates otherwise.
Optional or optionally means that the subsequently described event or circumstances can or may not occur. The description includes instances where the event or circumstance occurs and instances where it does not occur.
Ranges may be expressed herein as from about one particular value, and/or to about another particular value. When such a range is expressed, it is to be understood that another embodiment is from the one particular value and/or to the other particular value, along with all combinations within said range.
Throughout this application, where patents or publications are referenced, the disclosures of these references in their entireties are intended to be incorporated by reference into this application, in order to more fully describe the state of the art to which the disclosure pertains, except when these references contradict the statements made herein.
As used herein and in the appended claims, the words “comprise,” “has,” and “include” and all grammatical variations thereof are each intended to have an open, non-limiting meaning that does not exclude additional elements or steps.
As used herein, terms such as “first” and “second” are arbitrarily assigned and are merely intended to differentiate between two or more components of an apparatus. It is to be understood that the words “first” and “second” serve no other purpose and are not part of the name or description of the component, nor do they necessarily define a relative location or position of the component. Furthermore, it is to be understood that that the mere use of the term “first” and “second” does not require that there be any “third” component, although that possibility is contemplated under the scope of the present disclosure.
This U.S. non-provisional patent application declares priority to U.S. Provisional Patent Application No. 61/980,664, filed Apr. 17, 2014, the entire disclosure of which is hereby expressly incorporated herein by reference.
| Number | Name | Date | Kind |
|---|---|---|---|
| 1819055 | Al et al. | Aug 1931 | A |
| 1990969 | Wilson | Feb 1935 | A |
| 2094479 | Vandergrift | Sep 1937 | A |
| 2288556 | Vollmer | Jun 1942 | A |
| 2466674 | Mullady | Apr 1949 | A |
| 2606813 | Kahr | Aug 1952 | A |
| 2699213 | Cardwell et al. | Jan 1955 | A |
| 2885004 | Perry | May 1959 | A |
| 3025911 | Bergman | Mar 1962 | A |
| 3354954 | Buxton | Nov 1967 | A |
| 3385360 | Smith | May 1968 | A |
| 3405761 | Parker | Oct 1968 | A |
| 3476183 | Haynes, Jr., et al. | Nov 1969 | A |
| 3483923 | Darley | Dec 1969 | A |
| 3543856 | Knox et al. | Dec 1970 | A |
| 3568772 | Gogarty et al. | Mar 1971 | A |
| 3576596 | Kranc et al. | Apr 1971 | A |
| 3707192 | Goins, Jr. et al. | Dec 1972 | A |
| 3712380 | Caffey | Jan 1973 | A |
| 3719228 | Carcia | Mar 1973 | A |
| 3760881 | Kiel | Sep 1973 | A |
| 3828854 | Templeton et al. | Aug 1974 | A |
| 3864451 | Lee et al. | Feb 1975 | A |
| 4056146 | Hall | Nov 1977 | A |
| 4085799 | Bousaid et al. | Apr 1978 | A |
| 4136739 | Salathiel et al. | Jan 1979 | A |
| 4158042 | Deutschman | Jun 1979 | A |
| 4178993 | Richardson et al. | Dec 1979 | A |
| 4210628 | Ninomiya et al. | Jul 1980 | A |
| 4219083 | Richardson et al. | Aug 1980 | A |
| 4232740 | Park | Nov 1980 | A |
| 4232741 | Richardson et al. | Nov 1980 | A |
| 4291765 | Gilchrist et al. | Sep 1981 | A |
| 4330037 | Richardson et al. | May 1982 | A |
| 4399868 | Richardson et al. | Aug 1983 | A |
| 4410041 | Davies et al. | Oct 1983 | A |
| 4414118 | Murphey | Nov 1983 | A |
| 4454918 | Richardson et al. | Jun 1984 | A |
| 4475595 | Watkins et al. | Oct 1984 | A |
| 4482016 | Richardson | Nov 1984 | A |
| 4485007 | Tam et al. | Nov 1984 | A |
| 4491180 | Brown et al. | Jan 1985 | A |
| 4518040 | Middleton | May 1985 | A |
| 4572297 | Thigpen, Jr. et al. | Feb 1986 | A |
| 4615391 | Garthoffner | Oct 1986 | A |
| 4703803 | Blumer | Nov 1987 | A |
| 4832123 | Abou-Sayed et al. | May 1989 | A |
| 4842073 | Himes et al. | Jun 1989 | A |
| 4846277 | Khalil et al. | Jul 1989 | A |
| 4865826 | Carnell et al. | Sep 1989 | A |
| 4898750 | Friedman et al. | Feb 1990 | A |
| 4919209 | King | Apr 1990 | A |
| 5082058 | Blumer | Jan 1992 | A |
| 5087350 | Paris-Marcano | Feb 1992 | A |
| 5152906 | Aften et al. | Oct 1992 | A |
| 5183581 | Khalil et al. | Feb 1993 | A |
| 5197544 | Himes | Mar 1993 | A |
| 5209295 | Campos et al. | May 1993 | A |
| 5342530 | Aften et al. | Aug 1994 | A |
| 5358565 | Shu | Oct 1994 | A |
| 5375660 | Wehunt | Dec 1994 | A |
| 5411093 | Jennings, Jr. | May 1995 | A |
| 5411094 | Northrop | May 1995 | A |
| 5639313 | Khalil | Jun 1997 | A |
| 5958224 | Ho et al. | Sep 1999 | A |
| 6035933 | Khalil et al. | Mar 2000 | A |
| 6277271 | Kocal | Aug 2001 | B1 |
| 6500219 | Gunnerman | Dec 2002 | B1 |
| 6554071 | Crook | Apr 2003 | B1 |
| 6662874 | Surjaatmadja et al. | Dec 2003 | B2 |
| 6722434 | Reddy et al. | Apr 2004 | B2 |
| 6827845 | Gong et al. | Dec 2004 | B2 |
| 6881325 | Morris et al. | Apr 2005 | B2 |
| 6986392 | Chatterji | Jan 2006 | B2 |
| 6992048 | Reddy et al. | Jan 2006 | B2 |
| 7029639 | Yasutake et al. | Apr 2006 | B2 |
| 7059414 | Rae et al. | Jun 2006 | B2 |
| 7066260 | Sullivan et al. | Jun 2006 | B2 |
| 7153434 | Dennis | Dec 2006 | B1 |
| 7328746 | Al-Taq et al. | Feb 2008 | B2 |
| 7540328 | Brown et al. | Jun 2009 | B2 |
| 7589050 | Frenier et al. | Sep 2009 | B2 |
| 7624743 | Sarkar et al. | Dec 2009 | B2 |
| 7686084 | Reddy et al. | Mar 2010 | B2 |
| 7779915 | Hutchins et al. | Aug 2010 | B2 |
| 7947629 | Fuller | May 2011 | B2 |
| 8096361 | Willberg | Jan 2012 | B2 |
| 8216344 | Degenstein et al. | Jul 2012 | B2 |
| 8282715 | Degenstein et al. | Oct 2012 | B1 |
| 8962536 | Winslow et al. | Feb 2015 | B2 |
| 20030092581 | Crews | May 2003 | A1 |
| 20030221831 | Reddy et al. | Dec 2003 | A1 |
| 20050000694 | Dalrymple et al. | Jan 2005 | A1 |
| 20050215439 | Blair | Sep 2005 | A1 |
| 20060144591 | Gonzalez et al. | Jul 2006 | A1 |
| 20060154814 | Zanibelli et al. | Jul 2006 | A1 |
| 20060229212 | Willberg et al. | Oct 2006 | A1 |
| 20060258541 | Crews | Nov 2006 | A1 |
| 20080066784 | Sarkar et al. | Mar 2008 | A1 |
| 20080121395 | Reddy | May 2008 | A1 |
| 20080190607 | Minnich et al. | Aug 2008 | A1 |
| 20080190610 | Barmatov et al. | Aug 2008 | A1 |
| 20080289828 | Hutchins et al. | Nov 2008 | A1 |
| 20080318812 | Kakadjian, Sr. et al. | Dec 2008 | A1 |
| 20090098467 | Lowe et al. | Apr 2009 | A1 |
| 20100056399 | Berkland et al. | Mar 2010 | A1 |
| 20100170453 | Betzer-Zilevitch | Jul 2010 | A1 |
| 20100288499 | Al-Dhafeeri et al. | Nov 2010 | A1 |
| 20110030958 | Fedorov et al. | Feb 2011 | A1 |
| 20110203797 | Alexandrov et al. | Aug 2011 | A1 |
| 20110220360 | Lindvig et al. | Sep 2011 | A1 |
| 20120211225 | Kostrov et al. | Aug 2012 | A1 |
| 20130123151 | Crews | May 2013 | A1 |
| 20130126169 | Al-Nakhli et al. | May 2013 | A1 |
| 20130126175 | Al-Mulhem et al. | May 2013 | A1 |
| 20130180720 | Al-Dahlan et al. | Jul 2013 | A1 |
| 20140069644 | Reddy | Mar 2014 | A1 |
| 20140090839 | Al-Nakhil et al. | Apr 2014 | A1 |
| 20140144632 | Zavolzhski et al. | May 2014 | A1 |
| Number | Date | Country |
|---|---|---|
| 101323780 | Dec 2008 | CN |
| 101839123 | Sep 2010 | CN |
| 0654582 | May 1995 | EP |
| 0 909 873 | Apr 1999 | EP |
| 2001019984 | Jan 2001 | JP |
| 2100583 | Dec 1997 | RU |
| 2126084 | Feb 1999 | RU |
| 1677260 | Sep 1991 | SU |
| 0037777 | Jun 2000 | WO |
| 2006131895 | Dec 2006 | WO |
| 2008032067 | Mar 2008 | WO |
| 2009009370 | Jan 2009 | WO |
| 2009070561 | Jun 2009 | WO |
| 2010046618 | Apr 2010 | WO |
| 2010047612 | Apr 2010 | WO |
| 2012012224 | Jan 2012 | WO |
| 2012025150 | Mar 2012 | WO |
| 2012082402 | Jun 2012 | WO |
| 2013078306 | May 2013 | WO |
| Entry |
|---|
| Ashton, J.P., et al., “In-Situ Heat System Stimulates Paraffinic-Crude Producers in Gulf of Mexico,” SPE 15660, SPE Production Engineering, May 1989, pp. 157-160, vol. 4, No. 2, Society of Petroleum Engineers. |
| Database WPI, Week 201115, XP-002693470, Thomson Scientific, London, GB, C:\EPOPROGS\SEA\.\..\..\epodata\sea\eplogf\internal.log. |
| Khalil, C.N., et al., “Detection of Formation Damage Associated to Paraffin in Reservoirs of the Reconcavo Baiano, Brazil,” SPE 37238, Int'l Symposium on Oilfield Chemistry held in Houston, TX, Feb. 18-21, 1997, Society of Petroleum Engineers, Inc. |
| Kiryukhin, et al., Thermal-Hydrodynamic Modeling of Laboratory Tests on the Interaction of NaNO3—NaOH Fluids with Sandstone Rock at a Deep Radionuclide Repository Site, pp. 1-20, Russia. |
| Marques, L.C.C., et al., “A New Technique to Solve Gas Hydrate Problems in Subsea Christmas Trees.” SPE 77572, SPE Production & Facilities, Nov. 2004, pp. 253-258, Society of Petroleum Engineers. |
| PCT International Search Report and the written opinion dated Apr. 8, 2014; International Application No. PCT/US2013/043076; International filing date May 29, 2013. |
| Al-Nakhli, Chemically-Induced Pressure Pulse to Increase Stimulated Reservoir Volume in Unconventional Reservoirs, Unconventional Resources Technology Conference, Denver, CO, Aug. 25-27, 2014. |
| PCT Notification of Transmittal of the International Search Report and the Written Opinion of the International Searching Authority, or the Declaration; dated Mar. 18, 2013; International Appln No. PCT/US2013/021961; Int'l File Date: Jan. 17, 2013. |
| PCT Notification of Transmittal of the International Search Report and the Written Opinion of the International Searching Authority, or the Declaration; dated Mar. 5, 2013; International Appln No. PCT/US2012/066249; Int'l File Date: Nov. 21, 2012. |
| Schlumberger Systems, Sand Control Pumping, pp. 37-70, USA, available at www.slb.com/˜/media/files/sand—control/.../scps—03—systems.ashx. Feb. 27, 2012. |
| European Search Report and Written Opinion issued on Aug. 2, 2013, for related European Patent Application 13174172. |
| Anning Zhou et al., Deep Desulfurization of Diesel Fuels by Selective Adsorption with Activated Carbons, American Chemical Society, Washington, DC, vol. 49, No. 3, Jul. 1, 2004, pp. 329-332. |
| Yosuke Sano et al., Selection and Further Activation of Activated Carbons for Removal of Nitrogen Species in Gas Oil as a Pretreatment for its Deep Hydrodesulfurization, Energy & Fuels, vol. 18, Mar. 20, 2004, pp. 644-651. |
| Cheng Yun-Fu, Preparation and Field Uses of Heat Generating Hydrofracturing Fluids, Oilfield Chemistry Research Institute of Drilling and Production, Dagang Oil Fields, Dagang Oilfield Group Co., Ltd., vol. 14, No. pp. 24-27, Mar. 25, 1997. |
| Sano, “Two-step Adsorption Process for Deep Desulfurization of Diesel Oil,” Fuel 84 (2005) 903-910. |
| Examination Report issued Jun. 28, 2011 for related European Patent Application No. 08857250.9. |
| Isao Mochida, “Removal of SOx and NOx over activated carbon fibers,” Carbon, vol. 38, 2000 pp. 227-239. |
| Yosuke Sano, “Adsorptive Removal of Sulfur and Nitrogen Species from a Straight Run Gas Oil Over Activated Carbons for its Deep Hydrodesulfurization,” Applied Catalysis B: Environmental 49, 2004, pp. 219-225. |
| E. Raymundo-Pinero, “Temperature Programmed Desorption Study on the Mechanism of SO2 oxidation by Activated Carbon and Activated Carbon Fibres,” Carbon, vol. 39, 2001, pp. 231-242. |
| N. Shirahama, “Mechanistic Study on Adsorption and Reduction of NO2 Over Activated Carbon Fibers,” Carbon, vol. 40, 2002, pp. 2605-2611. |
| Isao Mochida, Kinetic Study of the Continuous Removal of SOx on Polyacrylonnitrile-Based Activated Carbon Fibres, Fuel vol. 76, No. 6, 1997, pp. 533-536. |
| Satoru Murata, “A Novel Oxidative Desulfurization System for Diesel Fuels with Molecular Oxygen in the Presence of Cobalt Catalysts and Aldehydes,” Energy & Fuels, vol. 18, No. 1, 2004, pp. 116-121. |
| Kazaumasa Yazu, “Immobolized Tungstophosphoric Acid-Catalyzed Oxidative Desulfurization of Diesel Oil with Hydrogen Peroxide,” Journal of Japan Petroleum Institute, vol. 46, No. 6, 2003, pp. 379-382. |
| Antonio Chica, “Catalytic Oxidative Desulfurization (ODS) of Diesel Fuel on a Continuous Fixed-Bed Reactor,” Journal of Catalysis, vol. 242, 2006, pp. 229-308. |
| Jeyagowry Sampanthar, “A Novel Oxidative Desulfurization Process to Remove Refractory Sulfur Compounds From Diesel Fuel,” Applied Catalysis B: Environmental 63, 2006, pp. 85-93. |
| Shujiro Otsuki, “Oxidative Desulfurization of Light Gas Oi and Vacuum Gas Oil by Oxidation and Solvent Extraction,” Energy & Fuels, vol. 14, No. 6, 2000, pp. 1232-1239. |
| Kazumasa Yazu, “Oxidative Desulfurization of Diesel Oil with Hydrogen Peroxide in the Presence of Acid Catalyst in Diesel Oil/Acetic Acid Biphase System,” Chemistry Letters, vol. 33, No. 10, 2004, pp. 1306-1307. |
| Paolo DeFilippis, “Oxidative Desulfurization: Oxidation Reactivity of Sulfur Compounds in Different Organic Matrixes,” Energy & Fuels, vol. 17, No. 6, 2003, pp. 1452-1455. |
| Mure Te, “Oxidation Reactivities of Dibenzothiophenes in Polyoxometalate/H202 and Formic Acid/H202 Systems,” Applied Catalysis A: General 219, 2001, pp. 267-280. |
| Isao Mochida, “Adsorption and Adsorbed Species of SO2 during its Oxidative Removal over Pitch-Based Activated Carbon Fibers,” Energy & Fuels, vol. 13, No. 2, 1999, pp. 369-373. |
| Xiang Gao, “Adsorption and Reduction of NO2 Over Activated Carbon at Low Temperature,” Fuel Processing Technology 92, 2011,pp. 139-146. |
| Related U.S. Appl. No. 14/689,874, filed Apr. 17, 2015, titled “Chemically-Induced Pulsed Fracturing Method”. |
| PCT International Search Report and the Written Opinion; dated Jun. 25, 2015; International Application No. PCT/US2015/026381; International File Date: Apr. 17, 2015. |
| Number | Date | Country | |
|---|---|---|---|
| 20150300142 A1 | Oct 2015 | US |
| Number | Date | Country | |
|---|---|---|---|
| 61980664 | Apr 2014 | US |