US20140338903A1 - Method for enhanced oil recovery by in situ carbon dioxide generation - Google Patents
Method for enhanced oil recovery by in situ carbon dioxide generation Download PDFInfo
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- US20140338903A1 US20140338903A1 US13/898,438 US201313898438A US2014338903A1 US 20140338903 A1 US20140338903 A1 US 20140338903A1 US 201313898438 A US201313898438 A US 201313898438A US 2014338903 A1 US2014338903 A1 US 2014338903A1
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- aqueous solution
- oil recovery
- carbon dioxide
- chelating agent
- reservoir
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- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 title claims abstract description 72
- 229910002092 carbon dioxide Inorganic materials 0.000 title claims abstract description 37
- 239000001569 carbon dioxide Substances 0.000 title claims abstract description 35
- 238000000034 method Methods 0.000 title claims abstract description 28
- 238000011084 recovery Methods 0.000 title claims abstract description 27
- 238000011065 in-situ storage Methods 0.000 title claims abstract description 12
- 239000002738 chelating agent Substances 0.000 claims abstract description 25
- 238000002347 injection Methods 0.000 claims abstract description 23
- 239000007924 injection Substances 0.000 claims abstract description 23
- 239000012530 fluid Substances 0.000 claims abstract description 20
- 239000007864 aqueous solution Substances 0.000 claims abstract description 19
- 239000000243 solution Substances 0.000 claims abstract description 13
- BVKZGUZCCUSVTD-UHFFFAOYSA-L Carbonate Chemical compound [O-]C([O-])=O BVKZGUZCCUSVTD-UHFFFAOYSA-L 0.000 claims abstract description 12
- 150000001732 carboxylic acid derivatives Chemical class 0.000 claims abstract description 12
- 239000013535 sea water Substances 0.000 claims abstract description 11
- 238000004519 manufacturing process Methods 0.000 claims description 3
- 239000011435 rock Substances 0.000 abstract description 8
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 abstract description 8
- 230000015572 biosynthetic process Effects 0.000 abstract description 6
- 238000005755 formation reaction Methods 0.000 abstract description 6
- 238000000605 extraction Methods 0.000 abstract description 3
- 239000011159 matrix material Substances 0.000 abstract description 3
- 239000003921 oil Substances 0.000 description 43
- 239000004094 surface-active agent Substances 0.000 description 7
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 6
- 239000011734 sodium Substances 0.000 description 6
- 239000010779 crude oil Substances 0.000 description 5
- 238000006073 displacement reaction Methods 0.000 description 5
- 238000002474 experimental method Methods 0.000 description 4
- 239000006260 foam Substances 0.000 description 4
- 239000007789 gas Substances 0.000 description 4
- 230000002378 acidificating effect Effects 0.000 description 3
- BVCZEBOGSOYJJT-UHFFFAOYSA-N ammonium carbamate Chemical compound [NH4+].NC([O-])=O BVCZEBOGSOYJJT-UHFFFAOYSA-N 0.000 description 3
- KXDHJXZQYSOELW-UHFFFAOYSA-N carbonic acid monoamide Natural products NC(O)=O KXDHJXZQYSOELW-UHFFFAOYSA-N 0.000 description 3
- 239000003795 chemical substances by application Substances 0.000 description 3
- 238000005260 corrosion Methods 0.000 description 3
- 230000007797 corrosion Effects 0.000 description 3
- 229920000642 polymer Polymers 0.000 description 3
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- 235000019738 Limestone Nutrition 0.000 description 2
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 description 2
- 239000000654 additive Substances 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- DIOQZVSQGTUSAI-UHFFFAOYSA-N decane Chemical compound CCCCCCCCCC DIOQZVSQGTUSAI-UHFFFAOYSA-N 0.000 description 2
- 239000004088 foaming agent Substances 0.000 description 2
- 230000005484 gravity Effects 0.000 description 2
- 239000003112 inhibitor Substances 0.000 description 2
- 239000006028 limestone Substances 0.000 description 2
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 239000011148 porous material Substances 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- KXDHJXZQYSOELW-UHFFFAOYSA-M Carbamate Chemical compound NC([O-])=O KXDHJXZQYSOELW-UHFFFAOYSA-M 0.000 description 1
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 238000013459 approach Methods 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 230000009977 dual effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005187 foaming Methods 0.000 description 1
- IXCSERBJSXMMFS-UHFFFAOYSA-N hcl hcl Chemical compound Cl.Cl IXCSERBJSXMMFS-UHFFFAOYSA-N 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- -1 hydrogen ions Chemical class 0.000 description 1
- 239000003915 liquefied petroleum gas Substances 0.000 description 1
- 238000013508 migration Methods 0.000 description 1
- 230000005012 migration Effects 0.000 description 1
- 239000003345 natural gas Substances 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 230000035699 permeability Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 238000012552 review Methods 0.000 description 1
- 239000004576 sand Substances 0.000 description 1
- 229910000029 sodium carbonate Inorganic materials 0.000 description 1
- 239000000080 wetting agent Substances 0.000 description 1
Images
Classifications
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B43/00—Methods or apparatus for obtaining oil, gas, water, soluble or meltable materials or a slurry of minerals from wells
- E21B43/16—Enhanced recovery methods for obtaining hydrocarbons
- E21B43/20—Displacing by water
-
- 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
- C09K8/58—Compositions for enhanced recovery methods for obtaining hydrocarbons, i.e. for improving the mobility of the oil, e.g. displacing fluids
-
- 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
- C09K8/58—Compositions for enhanced recovery methods for obtaining hydrocarbons, i.e. for improving the mobility of the oil, e.g. displacing fluids
- C09K8/594—Compositions used in combination with injected gas, e.g. CO2 orcarbonated gas
Definitions
- the present invention relates to oil recovery operations, and particularly to a method for enhanced oil recovery by in situ carbon dioxide generation.
- Enhanced oil recovery is a technique for increasing the amount of crude oil that can be extracted from an oil field.
- Gas injection, or miscible flooding is presently the most commonly used approach in enhanced oil recovery.
- Miscible flooding is a general term for injection processes that introduce miscible gases into the reservoir.
- a miscible displacement process maintains reservoir pressure and improves oil displacement because the interfacial tension between oil and water is reduced by removal of the interface between the two interacting fluids. This allows for total displacement efficiency.
- Gases used for miscible flooding include carbon dioxide, natural gas, and nitrogen.
- the fluid most commonly used for miscible displacement is carbon dioxide because of its ability to reduce the oil viscosity, coupled with its relatively low cost, particularly when compared to the more costly liquefied petroleum gas.
- Oil displacement by carbon dioxide injection relies on the phase behavior of the mixtures of the gas and the crude, which is strongly dependent on reservoir temperature, pressure and crude oil composition.
- carbon dioxide flooding processes frequently experience viscous fingering and gravity override problems because of the very low density and viscosity of the carbon dioxide when compared to those of crude oil. As a result, sweep efficiency is decreased, compared with more dense and/or viscous fluids, and significant amounts of oil are left behind.
- Enhanced oil recovery using carbon dioxide flooding typically requires the addition of mobility control agents to prevent the carbon dioxide from migrating to the upper part of the reservoir, particularly in thick reservoirs. This migration leaves the lower part of the reservoir unswept from oil.
- mobility control agents to prevent the carbon dioxide from migrating to the upper part of the reservoir, particularly in thick reservoirs. This migration leaves the lower part of the reservoir unswept from oil.
- foam processes which involve the injection of carbon dioxide together with an aqueous solution of a carbon dioxide-foaming agent.
- Carbon dioxide has a very low viscosity compared with both oil and water.
- its apparent viscosity is greatly increased and its mobility is improved.
- foam would preferentially impede flow in the higher permeability layers or fractures in the reservoir that had already been swept of their oil.
- the unswept parts of the reservoir would remain at least as accessible and available to have their content displaced and forced into the production wells.
- the overall success of the foaming process depends on foam concentration, compatibility with the reservoir rock, stability in solution over long periods of time, and thermal stability.
- Surfactants have been used as foaming agents, but surfactants suffer from thermal stability problems, typically being unstable at temperatures exceeding 100° C.
- HCl hydrochloric acid
- Another method for generating carbon dioxide in situ involves the injection of sodium carbonate with hydrochloric acid (HCl) into the formation, followed by reaction over a 24 hour period.
- HCl is very corrosive.
- costly corrosion inhibitors need to be added.
- the corrosion inhibitor may reverse the wettability of the formation, thus requiring water wetting agents to also be added.
- a further problem is that the HCl cannot be used in carbonate reservoirs due to the reaction between the HCl with the carbonate.
- the method for enhanced oil recovery by in situ carbon dioxide generation utilizes a chelating fluid injected into an oil reservoir through a fluid injection system.
- the chelating fluid is a low pH solution of a polyamino carboxylic acid chelating agent.
- the polyamino carboxylic acid chelating agent may have a concentration of about 5 wt %.
- the polyamino carboxylic acid chelating agent is preferably either an aqueous solution of H 2 Na 2 -ethylenediaminetetraacetic acid (pH 4.5), H 3 -hydroxyethyl ethylenediamine triacetic acid (pH 2.5), or an aqueous solution of H 2 NaHEDTA (pH 4).
- the chelating fluid may be injected at a rate of approximately 0.25 mL/min.
- the injection of the chelating fluid may be preceded by flooding the core with seawater, and is followed by injection of either seawater, a high pH chelating agent, or low salinity water to ensure maximal extraction of oil from the reservoir.
- the method is particularly for use in formations where the core of the reservoir has a carbonate rock matrix, since the carbon dioxide generation results from acidic liberation of carbon dioxide from the carbonate rock.
- FIG. 1 is a graph showing oil recovery using a low pH solution of H 3 -hydroxyethyl ethylenediaminetriacetic acid for in situ carbon dioxide generation for enhanced oil recovery according to the present invention.
- FIG. 2 is a graph showing oil recovery using a low pH solution of H 2 Na 2 -ethylenediaminetetraacetic acid for in situ carbon dioxide generation for enhanced oil recovery according to the present invention.
- the method for enhanced oil recovery by in situ carbon dioxide generation utilizes a chelating fluid injected into an oil reservoir through a fluid injection system.
- the chelating fluid is a low pH solution of a polyamino carboxylic acid chelating agent.
- the polyamino carboxylic acid chelating agent may have a concentration of about 5 wt %.
- the polyamino carboxylic acid chelating agent is preferably either an aqueous solution of H 2 Na 2 -ethylenediaminetetraacetic acid (pH 4.5), H 3 -hydroxyethyl ethylenediamine triacetic acid (pH 2.5), or an aqueous solution of H 2 NaHEDTA (pH 4).
- the chelating fluid may be injected at a rate of approximately 0.25 mL/min.
- the injection of the chelating fluid may be preceded by flooding the core with seawater, and is followed by injection of either seawater, a high pH chelating agent, or low salinity water to ensure maximal extraction of oil from the reservoir.
- the method is particularly for use in formations where the core of the reservoir has a carbonate rock (chalk and limestone) matrix (referred to as a carbonate reservoir), since the carbon dioxide generation results from acidic liberation of carbon dioxide from the carbonate rock.
- the low pH chelating agent will react with the carbonate rock and produce CO 2 that will diffuse to the oil and increases oil mobility so that more oil will be produced.
- the acidic part of the chelating agent that includes the hydrogen ions will produce the carbon dioxide from the carbonate rock formations.
- the high pH chelating agent, seawater, or low salinity water will displace the low pH chelating agent and the CO 2 .
- the method does not require the use of surfactants or other additives, and eliminates the problem of gravity override. Only a small volume of the aqueous solution of the low pH chelating agent is needed to generate the carbon dioxide, and when the concentration is limited to about 5%, no additives are required to prevent corrosion.
- H 2 Na 2 -ethylenediaminetetraacetic acid H 2 Na 2 -EDTA
- H 3 -hydroxyethyl ethylenediaminetriacetic acid H 3 -HEDTA
- H 2 Na 2 -EDTA H 2 Na 2 -ethylenediaminetetraacetic acid
- H 3 -HEDTA H 3 -hydroxyethyl ethylenediaminetriacetic acid
- FIG. 1 shows the effect of carbon dioxide generated from the use of the H 3 -HEDTA chelating agent at 5 wt % concentration and a pH of 2.5.
- the experiment was performed at 100° C. and at an injection rate of 0.25 mL/min.
- the core was first flooded by seawater, which recovered 58% of the initial oil from the core (i.e., 42% of the oil remained inside the core).
- a single pore volume of 5 wt % H 3 -HEDTA was injected into the core, and it recovered 34% oil from the oil in place or, in other words, 81% of the residual oil.
- One pore volume of 5 wt % H 3 -HEDTA produced enough carbon dioxide to recover more than 80% of the residual oil.
- FIG. 2 shows the results of a similar core flooding experiment with H 2 Na 2 -EDTA at a pH of 4.5. Continuous injection of this solution increased the oil recovery more than 90% from the initial oil in place. H 2 Na 2 -EDTA did not produce as much carbon dioxide as H 3 -HEDTA, thus larger volumes of the H 2 Na 2 -EDTA solution were required to recover an equivalent amount of oil. Further, in FIG. 2 , H 2 Na 2 -EDTA was tested against a 5 wt % conventional chelating agent, Na 4 -EDTA, with the H 2 Na 2 -EDTA solution clearly outperforming the conventional chelating solution of Na 4 -EDTA.
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- Mining & Mineral Resources (AREA)
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- Oil, Petroleum & Natural Gas (AREA)
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Abstract
The method for enhanced oil recovery by in situ carbon dioxide generation utilizes a chelating fluid injected into an oil reservoir through a fluid injection system. The chelating fluid is a low pH solution of a polyamino carboxylic acid chelating agent. The polyamino carboxylic acid chelating agent may have a concentration of about 5 wt %. The polyamino carboxylic acid chelating agent is preferably either an aqueous solution of H2Na2-ethylenediaminetetraacetic acid (pH 4.5), H3-hydroxyethyl ethylenediamine triacetic acid (pH 2.5), or an aqueous solution of H2NaHEDTA (pH 4). The injection of the chelating fluid may be preceded by flooding the core with seawater, and is followed by injection of either to seawater, a high pH chelating agent, or low salinity water to ensure maximal extraction of oil from the reservoir. The method is particularly for use in formations where the core of the reservoir has a carbonate rock matrix.
Description
- 1. Field of the Invention
- The present invention relates to oil recovery operations, and particularly to a method for enhanced oil recovery by in situ carbon dioxide generation.
- 2. Description of the Related Art
- Enhanced oil recovery (EOR) is a technique for increasing the amount of crude oil that can be extracted from an oil field. Gas injection, or miscible flooding, is presently the most commonly used approach in enhanced oil recovery. Miscible flooding is a general term for injection processes that introduce miscible gases into the reservoir. A miscible displacement process maintains reservoir pressure and improves oil displacement because the interfacial tension between oil and water is reduced by removal of the interface between the two interacting fluids. This allows for total displacement efficiency. Gases used for miscible flooding include carbon dioxide, natural gas, and nitrogen.
- The fluid most commonly used for miscible displacement is carbon dioxide because of its ability to reduce the oil viscosity, coupled with its relatively low cost, particularly when compared to the more costly liquefied petroleum gas. Oil displacement by carbon dioxide injection relies on the phase behavior of the mixtures of the gas and the crude, which is strongly dependent on reservoir temperature, pressure and crude oil composition. However, carbon dioxide flooding processes frequently experience viscous fingering and gravity override problems because of the very low density and viscosity of the carbon dioxide when compared to those of crude oil. As a result, sweep efficiency is decreased, compared with more dense and/or viscous fluids, and significant amounts of oil are left behind.
- Enhanced oil recovery using carbon dioxide flooding typically requires the addition of mobility control agents to prevent the carbon dioxide from migrating to the upper part of the reservoir, particularly in thick reservoirs. This migration leaves the lower part of the reservoir unswept from oil. The need for mobility control during carbon dioxide flooding has motivated research into foam processes, which involve the injection of carbon dioxide together with an aqueous solution of a carbon dioxide-foaming agent.
- Carbon dioxide has a very low viscosity compared with both oil and water. However, when carbon dioxide is in a dispersed phase, as in a foam, its apparent viscosity is greatly increased and its mobility is improved. In the past, it has been generally assumed that foam would preferentially impede flow in the higher permeability layers or fractures in the reservoir that had already been swept of their oil. In such a process, the unswept parts of the reservoir would remain at least as accessible and available to have their content displaced and forced into the production wells. The overall success of the foaming process depends on foam concentration, compatibility with the reservoir rock, stability in solution over long periods of time, and thermal stability. Surfactants have been used as foaming agents, but surfactants suffer from thermal stability problems, typically being unstable at temperatures exceeding 100° C.
- Due to the problems involved in the injection of carbon dioxide into the reservoir, there has been significant interest in generating carbon dioxide in situ. One prior technique used ammonium carbamate to produce a significant amount of carbon dioxide when the temperature rose to 85° C. Using ammonium carbamate in a one-dimensional sand pack column resulted in the production of carbon dioxide in the column at temperatures between 80° C. and 90° C., along with decreases in oil viscosity. The additional injection of a 0.5 vol % of 3% ammonium carbamate solution with a polymer/surfactant chemical flood improved crude oil recovery by 9.7% original oil in place (OOIP), compared to a polymer/surfactant chemical flood without carbamate. However, there was negligible oil recovery in experiments without the presence of surfactants when using light oils, decane and Arrow crude oil. Overall, oil recovery by this process was very low, with only 43% residual oil recovery after surfactant/polymer injection.
- Another method for generating carbon dioxide in situ involves the injection of sodium carbonate with hydrochloric acid (HCl) into the formation, followed by reaction over a 24 hour period. However, HCl is very corrosive. Thus, costly corrosion inhibitors need to be added. Further, the corrosion inhibitor may reverse the wettability of the formation, thus requiring water wetting agents to also be added. A further problem is that the HCl cannot be used in carbonate reservoirs due to the reaction between the HCl with the carbonate.
- Thus, a method for enhanced oil recovery by in situ carbon dioxide generation solving the aforementioned problems is desired.
- The method for enhanced oil recovery by in situ carbon dioxide generation utilizes a chelating fluid injected into an oil reservoir through a fluid injection system. The chelating fluid is a low pH solution of a polyamino carboxylic acid chelating agent. The polyamino carboxylic acid chelating agent may have a concentration of about 5 wt %. The polyamino carboxylic acid chelating agent is preferably either an aqueous solution of H2Na2-ethylenediaminetetraacetic acid (pH 4.5), H3-hydroxyethyl ethylenediamine triacetic acid (pH 2.5), or an aqueous solution of H2NaHEDTA (pH 4). The chelating fluid may be injected at a rate of approximately 0.25 mL/min. The injection of the chelating fluid may be preceded by flooding the core with seawater, and is followed by injection of either seawater, a high pH chelating agent, or low salinity water to ensure maximal extraction of oil from the reservoir. The method is particularly for use in formations where the core of the reservoir has a carbonate rock matrix, since the carbon dioxide generation results from acidic liberation of carbon dioxide from the carbonate rock.
- These and other features of the present invention will become readily apparent upon further review of the following specification.
-
FIG. 1 is a graph showing oil recovery using a low pH solution of H3-hydroxyethyl ethylenediaminetriacetic acid for in situ carbon dioxide generation for enhanced oil recovery according to the present invention. -
FIG. 2 is a graph showing oil recovery using a low pH solution of H2Na2-ethylenediaminetetraacetic acid for in situ carbon dioxide generation for enhanced oil recovery according to the present invention. - Similar reference characters denote corresponding features consistently throughout the attached drawings.
- The method for enhanced oil recovery by in situ carbon dioxide generation utilizes a chelating fluid injected into an oil reservoir through a fluid injection system. The chelating fluid is a low pH solution of a polyamino carboxylic acid chelating agent. The polyamino carboxylic acid chelating agent may have a concentration of about 5 wt %. The polyamino carboxylic acid chelating agent is preferably either an aqueous solution of H2Na2-ethylenediaminetetraacetic acid (pH 4.5), H3-hydroxyethyl ethylenediamine triacetic acid (pH 2.5), or an aqueous solution of H2NaHEDTA (pH 4). The chelating fluid may be injected at a rate of approximately 0.25 mL/min. The injection of the chelating fluid may be preceded by flooding the core with seawater, and is followed by injection of either seawater, a high pH chelating agent, or low salinity water to ensure maximal extraction of oil from the reservoir. The method is particularly for use in formations where the core of the reservoir has a carbonate rock (chalk and limestone) matrix (referred to as a carbonate reservoir), since the carbon dioxide generation results from acidic liberation of carbon dioxide from the carbonate rock.
- First, the low pH chelating agent will react with the carbonate rock and produce CO2 that will diffuse to the oil and increases oil mobility so that more oil will be produced. The acidic part of the chelating agent that includes the hydrogen ions will produce the carbon dioxide from the carbonate rock formations. Then, the high pH chelating agent, seawater, or low salinity water will displace the low pH chelating agent and the CO2. The method does not require the use of surfactants or other additives, and eliminates the problem of gravity override. Only a small volume of the aqueous solution of the low pH chelating agent is needed to generate the carbon dioxide, and when the concentration is limited to about 5%, no additives are required to prevent corrosion.
- In order to demonstrate the method, core flooding experiments were performed using Indiana limestone cores, each having a length of 5 inches, and a diameter of 1.5 inches. H2Na2-ethylenediaminetetraacetic acid (H2Na2-EDTA) with a pH of 4.5 and H3-hydroxyethyl ethylenediaminetriacetic acid (H3-HEDTA) with a pH of 2.5 were each tested as dual chelating agents and in situ carbon dioxide generating agents. Each agent was dissolved in water, and the solution was injected. The injection was followed by continuous injection of seawater or continuous injection of a high pH chelating agent.
-
FIG. 1 shows the effect of carbon dioxide generated from the use of the H3-HEDTA chelating agent at 5 wt % concentration and a pH of 2.5. The experiment was performed at 100° C. and at an injection rate of 0.25 mL/min. The core was first flooded by seawater, which recovered 58% of the initial oil from the core (i.e., 42% of the oil remained inside the core). A single pore volume of 5 wt % H3-HEDTA was injected into the core, and it recovered 34% oil from the oil in place or, in other words, 81% of the residual oil. One pore volume of 5 wt % H3-HEDTA produced enough carbon dioxide to recover more than 80% of the residual oil. -
FIG. 2 shows the results of a similar core flooding experiment with H2Na2-EDTA at a pH of 4.5. Continuous injection of this solution increased the oil recovery more than 90% from the initial oil in place. H2Na2-EDTA did not produce as much carbon dioxide as H3-HEDTA, thus larger volumes of the H2Na2-EDTA solution were required to recover an equivalent amount of oil. Further, inFIG. 2 , H2Na2-EDTA was tested against a 5 wt % conventional chelating agent, Na4-EDTA, with the H2Na2-EDTA solution clearly outperforming the conventional chelating solution of Na4-EDTA. - It is to be understood that the present invention is not limited to the embodiments described above, but encompasses any and all embodiments within the scope of the following claims.
Claims (7)
1. A method for enhanced oil recovery from a carbonate reservoir, comprising the steps of:
injecting an aqueous solution of a low pH polyamino carboxylic acid chelating agent into the core of the reservoir to generate the production of carbon dioxide in situ; and
subsequently injecting a fluid into the core to complete recovery of oil from the reservoir, the fluid being selected from the group consisting of seawater, a solution of a high pH chelating agent, and a low salinity fluid.
2. The method for enhanced oil recovery according to claim 1 , wherein the aqueous solution comprises an aqueous solution of H2Na2-ethylenediaminetetraacetic acid having a pH of about 4.5.
3. The method for enhanced oil recovery according to claim 1 , wherein the aqueous solution comprises an aqueous solution of H3-hydroxyethyl ethylenediamine triacetic acid having a pH of about 2.5.
4. The method for enhanced oil recovery according to claim 1 , wherein the aqueous solution comprises an aqueous solution of H2NaHEDTA having a pH of about 4.
5. The method for enhanced oil recovery according to claim 1 , wherein the aqueous solution has a concentration of about 5 wt %.
6. The method for enhanced oil recovery according to claim 1 , wherein said step of injecting the aqueous solution further comprises injecting the aqueous solution of a low pH polyamino carboxylic acid chelating agent at a temperature of about 100° C. and at an injection rate of 0.25 mL/min.
7. The method for enhanced oil recovery according to claim 1 , further comprising the step of flooding the core of the carbonate reservoir with seawater prior to said step of injecting the aqueous solution of the low pH polyamino carboxylic acid chelating agent into the core.
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Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3902556A (en) * | 1973-12-26 | 1975-09-02 | Texaco Inc | Secondary oil recovery method |
| US4410043A (en) * | 1982-05-26 | 1983-10-18 | Mobil Oil Corporation | Method for inhibition of carbonate dissolution in the recovery of oil utilizing CO2 |
| US20030104950A1 (en) * | 2001-10-25 | 2003-06-05 | Wayne Frenier | Treating composition |
| US20040009880A1 (en) * | 2002-07-09 | 2004-01-15 | Diankui Fu | Self-diverting pre-flush acid for sandstone |
| US20050061509A1 (en) * | 2003-08-26 | 2005-03-24 | Halliburton Energy Services, Inc. | Methods for prodcing fluids from acidized and consolidated portions of subterranean formations |
| US6911418B2 (en) * | 2001-05-17 | 2005-06-28 | Schlumberger Technology Corporation | Method for treating a subterranean formation |
| US20080039347A1 (en) * | 2004-07-13 | 2008-02-14 | Welton Thomas D | Treatment fluids comprising clarified xanthan and associated methods |
-
2013
- 2013-05-20 US US13/898,438 patent/US20140338903A1/en not_active Abandoned
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3902556A (en) * | 1973-12-26 | 1975-09-02 | Texaco Inc | Secondary oil recovery method |
| US4410043A (en) * | 1982-05-26 | 1983-10-18 | Mobil Oil Corporation | Method for inhibition of carbonate dissolution in the recovery of oil utilizing CO2 |
| US6911418B2 (en) * | 2001-05-17 | 2005-06-28 | Schlumberger Technology Corporation | Method for treating a subterranean formation |
| US20030104950A1 (en) * | 2001-10-25 | 2003-06-05 | Wayne Frenier | Treating composition |
| US20040009880A1 (en) * | 2002-07-09 | 2004-01-15 | Diankui Fu | Self-diverting pre-flush acid for sandstone |
| US20050061509A1 (en) * | 2003-08-26 | 2005-03-24 | Halliburton Energy Services, Inc. | Methods for prodcing fluids from acidized and consolidated portions of subterranean formations |
| US20080039347A1 (en) * | 2004-07-13 | 2008-02-14 | Welton Thomas D | Treatment fluids comprising clarified xanthan and associated methods |
| US7825073B2 (en) * | 2004-07-13 | 2010-11-02 | Halliburton Energy Services, Inc. | Treatment fluids comprising clarified xanthan and associated methods |
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|---|---|---|---|---|
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| CN108049854A (en) * | 2017-12-08 | 2018-05-18 | 中国石油化工股份有限公司 | Utilize CO2Drive the flooding method that additive improves oil recovery factor |
| CN108048066A (en) * | 2017-12-08 | 2018-05-18 | 中国石油化工股份有限公司 | Promote CO2The chemical assistant of gas drive process oil recovery factor |
| CN110068651A (en) * | 2018-01-23 | 2019-07-30 | 北京大学 | CO2Displacement of reservoir oil mixture-aid agent helps mixed effect evaluation method and CO2Displacement of reservoir oil mixture-aid agent screening technique |
| CN110273672A (en) * | 2018-03-14 | 2019-09-24 | 中国石油化工股份有限公司 | A kind of fracture-pore reservoir space structure well network design method based on the coefficient of variation |
| CN110273673A (en) * | 2018-03-14 | 2019-09-24 | 中国石油化工股份有限公司 | A kind of fracture-pore reservoir space structure flooding pattern optimum design method |
| CN109057762A (en) * | 2018-07-23 | 2018-12-21 | 中国石油大学(北京) | A kind of acidization tool of carbonate rock hydrocarbon reservoir |
| US10337304B1 (en) | 2018-08-30 | 2019-07-02 | Husky Oil Operations Limited | In-situ carbon dioxide generation for heavy oil recovery method |
| US10392911B1 (en) * | 2018-08-30 | 2019-08-27 | Husky Oil Operations Limited | In-situ carbon dioxide generation for heavy oil recovery method |
| CN111793489A (en) * | 2020-08-03 | 2020-10-20 | 西南石油大学 | A kind of carbonate rock reservoir in-situ gas generation foaming gel system and application method thereof |
| US11352867B2 (en) | 2020-08-26 | 2022-06-07 | Saudi Arabian Oil Company | Enhanced hydrocarbon recovery with electric current |
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| US11993746B2 (en) | 2022-09-29 | 2024-05-28 | Saudi Arabian Oil Company | Method of waterflooding using injection solutions containing dihydrogen phosphate |
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