METHOD FOR EXTRACTING HYDROCARBON COMPOUNDS, ESPECIALLY CRUDE OIL, FROM UNDERGROUND OIL SANDS DEPOSITS
A method for extracting hydrocarbon compounds, especially crude oil, from underground oil sands deposits, including the following steps: at least two parallel boring sections are created in the oil sands deposits; at least some areas of the boring sections are filled with an explosive material; the explosive material is ignited in order to enlarge the boring sections; the combustible material is ignited in at least one of the boring sections in order to convert the hydrocarbon compounds in the oil sands deposit into a liquid and/or gaseous state; the hydrocarbon compounds in a liquid and/or gaseous state are collected; and auxiliary substances such as water and atmospheric oxygen are optionally introduced and removed for desired material conversions for the refining of hydrocarbons.
The invention relates to a method for extracting hydrocarbon compounds, especially crude oil, from underground oil sand deposits.
Processes known as ISC (in situ-combustion) processes are known for the subterranean separation of low-fluidity bitumen from oil sand. In this process, the bitumen present in the oil sand is partly combusted and, for this purpose, air is injected into the porous oil sand, via a bore introduced into the oil sand deposit, in order to enable such combustion. The high-viscosity bitumen made fluid by the combustion is then pumped off via drainage pipes. In such processes, a firefront is produced within the oil sand deposit, and moves through the deposit. Controlling the firefront presents problems.
Alternative processes are based on the introduction of hot steam into the oil deposit, in order to make the high-viscosity bitumen fluid and allow it to be pumped off.
The aim of the invention is to improve a method for extracting hydrocarbon compounds, especially crude oil, from underground oil sand deposits.
According to the invention, a method is provided, for this purpose, for extracting hydrocarbon compounds, especially crude oil, from underground oil sand deposits, with the steps of introducing at least two bore sections parallel to one another into the oil sand deposit, of at least sectionally filling the bore sections with an explosive material, of detonating the explosive material to enlarge the bore sections, of igniting combustible material in at least one of the bore sections, to convert the hydrocarbon compounds present in the oil sand deposit into a liquid and/or gaseous state, and of collecting the hydrocarbon compounds present in a liquid and/or gaseous state.
The method of the invention permits improved in situ bitumen extraction and also improved upgrading of the hydrocarbon compounds with a higher and more rapid yield than in the case of the prior art described. By creating an underground cave system or cavern system through the introduction and enlargement of bore sections, the hydrocarbon compounds can be collected more easily and completely. Moreover, it is possible, for example, to blow in air, steam, or the like with substantially greater control and simplicity, since enlarged bore sections are available. In accordance with the invention, bores are sunk in the oil sand by means of a suitable drilling apparatus. After the bores have been introduced into the oil sand, bore sections lying within the oil sand are filled, at least sectionally, with an explosive material, and this explosive material is detonated. As a result, a stable, approximately cylindrical cavern is formed in the oil sand. At least two such caverns are produced parallel to one another. Then, in at least one of the caverns, combustible material or ignitable mixture is provided, for example, by the pumped introduction of additional air, and this material or mixture is then ignited by means, for example, of pyrotechnic detonating charges. The combustion is then maintained. Hot combustion gases then penetrate the porous oil sand and liquefy the bitumen in the sand. The combustion then progresses also preferably in the radial direction into the surrounding oil sand. In the cavern itself, liquid and/or gaseous bitumen and/or other hydrocarbon compounds then collect, and can then simply be pumped off. Through targeted, blown introduction of air and water/steam or other substances, temperature conversions and physical conversions within the caverns can be influenced. When the bitumen source is exhausted, i.e., the combustion zones and/or the liquefaction zones, which advance in the radial direction from the two caverns, come together, the supply of air is shut off. Optionally, CO2 may be pumped in to halt the combustion reliably. The bore sections can be enlarged underground without problems, by detonation of the explosive material, and this enlargement represents the precondition for a decisive improvement in the method of the invention, as has already been the case in particular with regard to the more rapid, more complete, and more secure collecting of liquid or gaseous hydrocarbon compounds, and also in respect of the more controlled propagation of a flame front in the oil sand.
In development of the invention, there is compacting of the oil sand material surrounding the outer surface of the bore sections, by means of the enlarging of the bore sections after detonating of the explosive material.
Compacting the oil sand material produces stable caverns which can be utilized for the passage of gaseous and liquid hydrocarbon compounds and also of additives, and also for the combustion of combustible material. Especially in the case of porous and plastically deformable oil sand, such compaction may take place very easily by detonation of explosive material in a bore section.
In development of the invention, air is supplied to the bore sections to promote the combustion of the combustible material, and off-gases formed during combustion are drawn off under suction.
In this way it is possible to maintain controlled combustion with predetermined parameters in the enlarged bore sections. Since the enlarged bore sections form caverns, such control or regulation of combustion can take place reliably, since physical exchange is possible comparatively rapidly in the volume of the caverns, in any case significantly more rapidly than would be the case for the blown introduction of air or gases in porous oil sand.
In development of the invention, water, steam, oxygen, carbon monoxide and/or carbon dioxide is supplied to or targetedly withdrawn from the bore sections in order to influence temperature and physical conversions in the region of the bore sections; in this case, carbon monoxide and/or carbon dioxide may also come from the combustion itself.
In this way it is possible to design an underground refinery with controllable combustion parameters, physical conversion (upgrading) parameters, mass transport parameters, and heat transport parameters in the caverns formed by enlargement of the bore sections. For example, with the aid of gravity and of the flow regime of gases, more particularly air, combustion gases, pyrolysis vapors or smolder vapors, hydrocarbon vapors, etc., and liquids (hot bitumen and crude oil) can be specifically influenced. Temperature zones can be influenced in just the same advantageous way. In addition, as in the case of above-ground upgrading processes, specific physical conversions can be achieved and therefore partially cracked bitumen also upgraded by hydrogen hydrotreating (synthetic crude oil) can be synthesized underground. This is accomplished, for example, by occasional (intermittent) or continuous injection of water or steam into a cavern filled with combustion gases and bitumen vapors. In a manner similar to steamcracking or thermal cracking, long-chain hydrocarbon molecules are split, and subsequently, using synthesis gas (CO and H2 from steam and pyrolysis coke), unsaturated, short-chain hydrocarbon molecules are saturated with resultant hydrogen, also called hydrotreating. In order to control combustion or to extinguish the combustion zone, after the end of exploitation of the deposit, using CO2 introduced by pumping, carbon dioxide, for example, can be pumped in. In this way it is also possible to a certain extent to store CO2.
In development of the invention, the hydrocarbon compounds present in the oil sand deposit are split by means of the combustion into hydrocarbon chains of different lengths and different aggregate states, with short-chain, lighter and/or gaseous chain components rising upward, and long-chain, heavier and/or liquid chain components falling downward. In specific secondary reactions, hydrogen is formed from water, in order to upgrade the hydrocarbons by hydrotreating.
In this way, by means of the geometry of the enlarged bore sections and the skillful arrangement of a plurality of enlarged bore sections, physical partition within the caverns can be influenced.
In development of the invention, the combustion of the combustible material is extinguished by the pumped introduction of an extinguishant, more particularly by means of an extinguishing gas, CO2 for example.
Combustion within the oil sand deposit or else only within the enlarged bore sections can be fully or partly extinguished in this way, in order to be able to control combustion rate and temperature, for example.
In development of the invention, provision is made for introducing a first, substantially vertical bore section down into the oil sand deposit, for introducing a second, substantially horizontal bore section into the oil sand deposit, starting from the first, vertical bore section, for introducing at least one third, substantially horizontal bore section into the oil sand deposit, starting from the first, vertical bore section or starting from a fourth, vertical bore section, the third, horizontal bore section being arranged with a vertical and/or horizontal offset from the second, horizontal bore section and running substantially parallel thereto, for at least sectional filling of the second, horizontal bore section and of the third, horizontal bore section with an explosive material, and for detonation of this explosive material, to enlarge the second, horizontal and third, horizontal bore sections, for ignition of combustible material in the second and/or third, horizontal bore section(s), to convert the hydrocarbon compounds present in the oil sand deposit into a liquid and/or gaseous state, and for collection of the liquid and/or gaseous hydrocarbon compounds.
In this way a particularly advantageous arrangement of the individual enlarged bore sections with respect to one another is achieved.
In development of the invention, two or more second, horizontal bore sections and two or more third, horizontal bore sections are arranged in planes which each run parallel to one another.
In this way, a matrix of enlarged bore sections can be formed within the oil sand deposit, this being extremely advantageous for controlled propagation of a flame front in the oil sand deposit and also for the creation of defined sinks or collecting basins for liquid and/or gaseous hydrocarbon compounds. The oil sand deposits can be exploited more completely and also more environmentally as a result, since, for example, combustion processes can be extinguished completely by blown introduction of CO2.
In development of the invention, two or more second, horizontal bore sections and two or more third, horizontal bore sections are arranged in a plane at a predetermined distance from one another.
In development of the invention, provision is made for introducing at least one first, substantially vertical bore section down into the oil sand deposit, for introducing at least one fourth, substantially vertical bore section down into the oil sand deposit, substantially parallel to the first, vertical bore section, for at least sectional filling of the first and/or fourth vertical bore section(s) with an explosive material, and for detonating this explosive material, to enlarge the first and/or fourth vertical bore section(s), for igniting combustible material in the first and/or fourth vertical bore section(s), to convert the hydrocarbon compounds present in the oil sand deposit into a liquid and/or gaseous state, and for collecting the liquid and/or gaseous hydro-carbon compounds.
In this way, enlarged bore sections or caverns arranged vertically can be provided. Then, as in the case of rectifying columns, gases, vapors, and liquids can be fed in and tapped off at different heights. In this way as well it is possible to design an underground refinery.
In development of the invention, the first and fourth vertical bore sections are connected by means of horizontal bore sections, with at least one horizontal bore section connecting the vertical bore sections in an upper region, and at least one horizontal bore section connecting the vertical bore sections in a lower region.
In this way it is possible to enable a targeted flow regime in the underground caverns.
In development of the invention, at least one bore section is sealed off from the atmosphere. For example, connections between the underground caverns and the atmosphere are sealed off provisionally, at least partly, by means of an expandable or inflatable plug. An expandable plug casing is first expanded, for example, with air and/or with a fluid, resulting in an impervious seal in the borehole. Alternatively or additionally to air, for example, water, bentonite slurry, or flowable concrete can also be used for filling. This plug can thereafter be backfilled, for example with sand, gravel, bentonite slurry and/or concrete. In this way a cavern can be sealed off from the atmosphere or else from other caverns, in order to create an underground system of caverns and connections that can be utilized as an underground refinery.
Further features and advantages of the invention will become apparent from the claims and from the following description of preferred embodiments of the invention, in connection with the drawings. Individual features of the different embodiments shown may be combined arbitrarily with one another, without exceeding the scope of the invention. In the drawings:
The representation in
This gellike explosive is then detonated—see
In accordance with
Arranged beneath the two caverns 24 and 30 is a pumping pipe 32, which communicates with a pumping station 34 on the Earth's surface 10.
Into both the underground cavern 24 and the underground cavern 30, combustible material is next either introduced, or combustible material is formed within the caverns 24 and 30 by the introduction of additives, as for example the blown introduction of air. The combustible material then present within the caverns 24 and 30, combustible gas for example, is then ignited by pyrotechnic means, for example, so that combustion develops and a flame front propagates, starting from the two caverns 24 and 30. One such flame front is indicated in the case of the cavern with the reference numeral 36. The pressure produced as a result of the combustion within the caverns 24 and 30 ensures a flow of gas in the direction of the arrows 38 and 40, in other words from the cavern 24 toward the cavern 30, and in the opposite direction. The oil sand deposit 14 consists of porous material, and so combustion and an associated flow of gas can propagate within the oil sand deposit 14. The progress of the flame front 36 between the two caverns 24 and 30, with a flame front surrounding the cavern 24 not being shown, ensures heating of the oil sand situated between the two caverns 24 and 30, and, consequently, ensures liquefaction of the bitumen situated between the two caverns 24 and 30. This liquefied bitumen can then be pumped off via the bore 32; however, the liquefied bitumen will also collect within the caverns 24 and 30 and can then easily be pumped off from these caverns. The same applies to gaseous hydrocarbon compounds, which will preferably collect within the caverns 24 and 30.
Following depletion of the oil sand deposit 14 in the region between the caverns 24 and 30, combustion can be extinguished by pumping CO2 into the caverns 24 and 30. This CO2 will then spread, starting from the caverns 24 and 30 and likewise in the direction of the arrows 38 and 40, toward the respective opposite cavern 30 or 24, and the combustion of the oil sand deposit will be completely extinguished as a result. This pumped introduction of CO2 may be used not only to extinguish the combustion but also, at the same time, for the permanent storage of CO2.
The representation in
The underground caverns 42, 44, and 46 arranged horizontally, roughly at the same height, and parallel to one another within the oil sand deposit 14 are connected to one another by means of horizontal bores 50 and 52. The horizontal bore sections 50 and 52 are arranged roughly flush and/or offset from one another and are continued in the form of substantially vertically running bore sections 54 and 56 and taken to pumping stations 58 and 60 at the Earth's surface. Starting from the pumping station 58, a substantially vertical bore section 54 leads to the cavern 42, and is then continued by means of the bore section 50 to the cavern 44. Starting from the cavern 44, a flow connection exists via the bore section 52 to the cavern 46, and from there the substantially vertical bore section 56 leads to the pumping station 60. The arrangement in
The arrangement shown schematically in
The representation in
The representation in
In the deepest cavern 86, on the left in
The representation in
The representation in
The arrangement of underground bore sections and caverns shown in
The representation in
According to
The arrangement of the underground caverns 128, 130, and 132 that is shown in
Claims
1. A method for extracting hydrocarbon compounds, especially crude oil, from underground oil sand deposits, with the steps of
- introducing at least two bore sections parallel to one another into the oil sand deposit,
- at least sectionally filling the bore sections with an explosive material,
- detonating the explosive material to enlarge the bore sections,
- igniting combustible material in at least one of the bore sections, to convert the hydrocarbon compounds present in the oil sand deposit into a liquid and/or gaseous state, and
- collecting the hydrocarbon compounds present in a liquid and/or gaseous state.
2. The method as claimed in claim 1, including compacting of the oil sand material surrounding the outer surface of the bore sections, by means of the enlarging of the bore sections after detonating of the explosive material.
3. The method as claimed in claim 1, wherein the explosive material is a gellike explosive.
4. The method as claimed in claim 1, wherein air is supplied to the bore sections to promote the combustion of the combustible material, and in that off-gases formed during combustion are drawn off under suction.
5. The method as claimed in claim 1, wherein water, steam, oxygen, more particularly atmospheric oxygen, carbon monoxide and/or carbon dioxide is supplied to or targetedly withdrawn from the bore sections in order to influence temperature and physical conversions, such as cracking and upgrading, for example, in the region of the bore sections.
6. The method as claimed in claim 1, wherein the hydrocarbon compounds present in the oil sand deposit are split by means of the combustion into hydrocarbon chains of different lengths and different aggregate states, with short-chain, lighter and/or gaseous chain components rising upward, and long-chain, heavier and/or liquid chain components falling downward.
7. The method as claimed in claim 1, wherein the combustion of the combustible material is extinguished by the pumped introduction of an extinguishant, more particularly by means of an extinguishing gas, CO2 for example.
8. The method as claimed in claim 1, including sealing off at least one bore section from the atmosphere.
9. The method as claimed in claim 1, with the steps of
- introducing a first, substantially vertical bore section down into the oil sand deposit,
- introducing a second, substantially horizontal bore section into the oil sand deposit, starting from the first, vertical bore section,
- introducing at least one third, substantially horizontal bore section into the oil sand deposit, starting from the first, vertical bore section or starting from a fourth, vertical bore section, the third, horizontal bore section being arranged with a vertical and/or horizontal offset from the second, horizontal bore section and running substantially parallel thereto,
- at least sectionally filling the second, horizontal bore section and the third, horizontal bore section with an explosive material, and detonating this explosive material to enlarge the second, horizontal and third, horizontal bore sections,
- igniting combustible material in the second and/or third, horizontal bore section(s), to convert the hydrocarbon compounds present in the oil sand deposit into a liquid and/or gaseous state, and
- collecting the liquid and/or gaseous hydrocarbon compounds.
10. The method as claimed in claim 9, wherein two or more second, horizontal bore sections and two or more third, horizontal bore sections are arranged in planes which each run parallel to one another.
11. The method as claimed in claim 1, wherein two or more second, horizontal bore sections and two or more third, horizontal bore sections are arranged in a plane at a predetermined distance from one another.
12. The method as claimed in claim 1, with the steps of
- introducing at least one first, substantially vertical bore section down into the oil sand deposit,
- introducing at least one fourth, substantially vertical bore section down into the oil sand deposit, substantially parallel to the first, vertical bore section, characterized by
- at least sectionally filling the first and/or fourth vertical bore section(s) with an explosive material, and detonating this explosive material to enlarge the first and/or fourth vertical bore section(s),
- igniting combustible material in the first and/or fourth vertical bore section(s), to convert the hydrocarbon compounds present in the oil sand deposit into a liquid and/or gaseous state, and
- collecting the liquid and/or gaseous hydrocarbon compounds.
13. The method as claimed in claim 12, including connecting the first and fourth vertical bore sections by means of horizontal bore sections, with at least one horizontal bore section connecting the vertical bore sections in an upper region, and at least one horizontal bore section connecting the vertical bore sections in a lower region.
Type: Application
Filed: Mar 7, 2012
Publication Date: Feb 6, 2014
Inventors: Ralph Eisenschmid (Marbach), Hans-Kurt Schromm (Backnang), Matthias Kleinhans (Waiblingen)
Application Number: 14/112,282
International Classification: E21B 43/248 (20060101);