DE102012014657A1 - Apparatus and method for recovering carbonaceous substances from oil sands - Google Patents

Abstract

The invention relates to a device for extracting carbonaceous substances, in particular bitumen, from oil sands. The device comprises at least one steam generator (1), an injection pipe (2) and a production pipe (3). At least one steam turbine (4) is arranged between the steam generator (1) and the injection pipeline (2) and is connected on the drive side to a first generator (G1) for generating electricity. The device comprises an electric / electromagnetic heater (5) for heating the oil sands, wherein the electric / electromagnetic heater (5) can be operated with electric current which is generated by means of the first generator (G1). The invention also relates to a method for obtaining carbonaceous substances, in particular bitumen, from oil sands by means of such a device.

Description

The invention relates to a device and a method for obtaining carbonaceous substances, in particular bitumen, from oil sands.

Large parts of the world's oil reserves are in the form of oil sands. Oil sands are a mixture of rock, clay, sand, water and bitumen or other heavy oils. Below is to be spoken of representative of heavy, heavy oils or generally long-chain hydrocarbons only of bitumen, which typically occur with a viscosity of API 5 ° to 15 ° lagersstättenmäßig. By appropriate process steps, the bitumen can be converted into synthetic crude oil.

Oil sands occurrences, if they lie in shallow layers of earth, are preferentially mined in the open pit. In many cases, however, are oil sands deposits in deeper layers of the earth, which are not accessible to open-pit mining or their mining would be unprofitable in open-pit mining. Typically, oil sands deposits are mined from depths of about 60 m with so-called in situ method. Since in these methods, the degradation of the top layer, which is above the oil sands occurrence, is not necessary.

The most widely used in situ method is Steam Assisted Gravity Drainage (SAGD). In the SAGD process, the bitumen present in a soil in the soil is heated by superheated steam. Due to the effect of heat, the long-chain hydrocarbons of the high-viscosity bitumen are split. The heating of the oil sand leads to a reduction in the viscosity of the bitumen, which is thereby flowable and can be conventionally pumped out of the reservoir.

The apparatus for the sawing process comprises at least one injection pipe for feeding the hot steam into the deposit and a production pipeline through which the liquid bitumen from the deposit can be conveyed to the earth's surface. The injection pipeline and the production pipeline are laid essentially parallel to one another and horizontally one above the other within the deposit. The injection pipe and the production pipe usually have a distance of about 5 m to 10 m in the vertical direction to each other. In the horizontal direction, the pipes extend within the deposit over a length of between several 100 m and a few kilometers. The injection tubing is typically above the production tubing. Due to the heating and the reduction of the viscosity of the bitumen, the bitumen flows downwards due to gravity and thus to the production pipeline, where it can be pumped off in a simple manner and conveyed to the earth's surface. The production can be achieved either with lifting oil pumps or by introducing an overpressure in the deposit. However, the introduction of overpressure has the significant disadvantage that it may come in the vicinity of the deposit to the ground surface (blowout). In particular, when the layer of soil above the deposit is of small thickness. For this reason, usually the vapor pressure before introduction into the deposit is reduced by means of a throttle or a throttle valve to a pressure which is lower than the rock pressure in the region of the deposit. The throttle valve is arranged between the steam generator and the injection pipeline. Since the vapor pressure is dissipated unused in the throttle valve, the process is not very effective.

For this reason, in the not pre-published German patent application 10 2012 000 092.8 entitled "Applicant's apparatus and method for recovering carbonaceous substances from oil sands" proposed to arrange at least one steam turbine between the steam generator and the injection pipe. The arrangement of the steam turbine between the steam generator and the injection pipe, the pressure reduction, which is usually unused via the throttle valve, are used for energy recovery. For this purpose, the steam turbine is preferably connected to a generator for generating electricity.

Another common in situ method is the Electro Magnetic Gravity Drainage (EMGD). In the EMGD process, the heating of the deposit takes place by means of an electric / electromagnetic heating process, in which, in particular, an inductive heating takes place. The EMGD procedure is in the German patent application 10 2007 040605.5 entitled "Applicant's in situ production of bitumen or heavy oil". Also, the EMGD method is associated with a large amount of energy.

Object of the present invention is therefore to further develop the known in situ method such that the efficiency of the device is increased. At the same time it is an object of the present invention to provide a corresponding method for the production of carbonaceous substances.

The object is achieved with regard to the device by the features of independent claim 1 and with respect to the method by the features of independent claim 4.

Further embodiments and advantages of the invention, which are used individually or in combination with each other, are the subject of the dependent claims.

The device according to the invention for the production of carbonaceous substances, in particular bitumen, from oil sands comprising at least one steam generator, an injection pipe and a production pipeline, wherein steam is introduced into the oil sand via the injection pipe and the carbonaceous substances are discharged from the oil sands via the production pipeline and wherein between the steam generator and the injection pipe at least one steam turbine is arranged, which is connected on the output side with a first generator for generating electricity, characterized in that the device comprises an electric / electromagnetic heater for heating the oil sands, which with electric current, which by means of first generator is generated, is operable. By means of the device according to the invention, on the one hand the steam which is conducted from the steam generator to the steam turbine is relieved within the steam turbine to a pressure which is equal to or less than the rock pressure in the region of the deposit and at the same time the electric current generated by the steam turbine can be used in addition to the electrical / electromagnetic heating of the deposit can be used. By the direct and immediate use of the electric current from the first generator, which is arranged on the output side of the steam turbine, the electrical losses are reduced to a minimum and increased the efficiency of the entire device.

An embodiment of the invention provides that the device comprises at least one heat engine, in particular a gas turbine, which is connected on the output side with a second generator for generating electricity, and the electric current, which is generated by means of the second generator, for simultaneous or alternative heating of the Oil sands can be used by means of electrical / electromagnetic heating. By using an additional heat engine, in particular gas turbine, the electrical power and thus the electric heating power of the electric / electromagnetic heating can be increased. The heat engine can be chosen so that it covers the electrical needs as well as possible. In this case, the heat engine can also serve to generate electricity, which is in the system, especially for ancillaries needed.

A further embodiment of the invention provides that the steam generation takes place by means of a heat exchanger, wherein the hot exhaust gas of the heat engine is used to generate steam. The heat energy of the exhaust gas can preferably be removed by means of the heat exchanger to the steam cycle. For this purpose, the exhaust gas flow is conducted in countercurrent to the steam of the steam cycle. By using the hot exhaust gas of the heat engine to evaporate the water in the steam cycle, the efficiency of the device according to the invention is further improved.

• – Erzeugen von Dampf im Dampferzeuger;
• – Zuführen des Dampfes zur Dampfturbine;
• – Entspannen des Dampfes in der Dampfturbine auf einem Dampfdruck der kleiner oder gleich dem Gesteinsdruck der Lagerstätte ist;
• – Einleiten des Dampfes über die Injektionsrohrleitung in die Lagerstätte;
• – Speisen der elektrischen/elektromagnetischen Heizung mit elektrischen Strom vom ersten und/oder zweiten Generator;
• – Erwärmen des Ölsandes mittels des Dampfes und der elektrischen/elektromagnetischen Heizung und Aufspalten der langkettigen Kohlenwasserstoffe der kohlenstoffhaltigen Substanzen;
• – Abführen der kohlenstoffhaltigen Substanzen über die Produktionsrohrleitung.

The process according to the invention for obtaining carbonaceous substances, in particular bitumen, from oil sands by means of a device according to one of the preceding claims, is characterized by the following process steps:

• - generating steam in the steam generator;
• - supplying the steam to the steam turbine;
• - depressurizing the steam in the steam turbine at a vapor pressure which is less than or equal to the rock pressure of the reservoir;
• - introducing the steam via the injection pipeline into the reservoir;
• - feeding the electric / electromagnetic heating with electric power from the first and / or second generator;
• - Heating the oil sand by means of the steam and the electric / electromagnetic heating and splitting the long-chain hydrocarbons of the carbonaceous substances;
• - Passing the carbonaceous substances through the production pipeline.

The inventive method is particularly effective due to the simultaneous heating of the deposit by the electrical / electromagnetic heating and the introduction of hot steam. By using the electric current which is generated by the first generator, which is connected on the output side to the steam turbine, a particularly high efficiency of the method results. The efficiency of the method is further increased, characterized in that preferably a heat engine is used, the exhaust gas is used to generate steam in the steam cycle.

The inventive device and the inventive method for the production of carbonaceous substances, especially bitumen, from oil sands, thus represents a significant increase in efficiency over the previously used devices and methods. The vapor pressure must be reduced, is the first time to generate electricity for operating an electric / electromagnetic heating, used to heat the deposit.

Further advantages of the invention, which can be used individually or in combination with each other, are described below with reference to a Embodiment explained. The embodiment shows a schematic and simplified representation of the device according to the invention, in which the essential components of the invention are shown.

For the detailed description of the methods (SAGD and EMGD), reference is made at this point to the prior art already cited in the introduction, the disclosure content of which comprises the invention.

1 shows an embodiment of a device according to the invention for the production of carbonaceous substances, in particular bitumen from oil sands. The oil sands are in a deposit 9 in the soil. The deposit 9 lies in a depth in which the mining of oil sands in open pit economically not profitable. For this reason, the bitumen is degraded in-situ.

The device according to the invention for such a method comprises at least one steam generator 1 , an injection pipeline 2 as well as a production pipeline 3 , The injection pipeline 2 as well as the production pipeline 3 Usually run horizontally within the deposit 9 (in 1 not shown). The injection pipeline 2 and the production pipeline 3 run parallel and usually at a distance of about 5 m to 10 m to each other. In the horizontal direction, the pipes extend within the deposit 9 over a length of several 100 m and a few kilometers. Before the bitumen from the deposit 9 The deposit must be extracted 9 are first heated to reduce the viscosity of the bitumen present in the oil sands or in the oil stone. The warming leads to a splitting of the long-chain carbons, the high-viscosity bitumen, whereby the viscosity decreases and the bitumen becomes free-flowing. Heating the deposit 9 takes place by introducing the steam generator 1 generated steam via the injection pipeline 2 , The flowable bitumen sinks due to gravity down and can then be promoted as bitumen-water emulsion to light. To promote simple lifting oil pumps (not shown) are suitable. The bitumen-water emulsion can then be separated in a corresponding treatment plant. The water of the bitumen-water emulsion is largely recovered and via a corresponding return line 10 again the steam generator 1 fed. The steam flowing through the injection pipe 2 into the deposit 9 must be previously reduced to a pressure which is below the rock pressure, otherwise it can lead to earth faults on the surface (blowout). This effect occurs in particular when the soil above the deposits 9 of small thickness and density. Because the pressure of the steam behind the steam generator 1 is very high, the steam pressure can be used to a steam turbine 4 drive. As a result, the pressure energy of the steam is converted into kinetic energy. The steam can then escape to the steam turbine 4 via the injection pipeline 2 into the deposit 9 be directed. The output side is to the steam turbine 4 a first generator G1 arranged. The generator G1 generates electrical energy. The electrical energy generated by the generator G1 can be used directly to heat the deposit 9 be used. For this purpose, the device according to the invention comprises an electrical / electromagnetic heating 5 , The electric / electromagnetic heating 5 is also in the ground 9 moves and heats the soil 9 in addition to steam heating. This leads to a particularly good warming of the soil and thus to a particularly effective reduction of the viscosity of the bitumen and to a particularly effective splitting of the long-chain carbon compounds. As a result, the deposit can be mined particularly economically.

The device according to the invention preferably further comprises a gas turbine 6 , To the gas turbine 6 on the output side, a second generator G2 is connected. The second generator G2 also supplies power for the electrical / electromagnetic heating 5 , In addition, the electrical power produced by the generator G2 can be used for the system, in particular for ancillary components of the systems. Depending on the required electrical energy requirement, the gas turbine 6 designed accordingly. In principle, it is also possible that the steam turbine and the gas turbine sit on a shaft and operate a single generator. By appropriate circuits, it is also possible that the electrical / electromagnetic heating is supplied only by the generator G1 or only by the generator G2 or by both generators simultaneously.

The exhaust gas flow of the heat engine (gas turbine) 6 is used for steam generation in the steam cycle. This is the steam generator 1 as a heat exchanger 7 educated. The hot exhaust of the heat engine 6 flows through the heat exchanger 7 preferably in countercurrent, thereby heating the water / steam in the steam cycle and thus ensures evaporation. In addition, another firing of the steam generator 1 be provided. By using the exhaust gas of the heat engine 6 a further increase in efficiency of the device is achieved.

Subsequently, the inventive method for obtaining carbonaceous substances, in particular bitumen from oil sands, by means of the device described above is short explained. First, in the steam generator 1 Steam generated. The steam is then the steam turbine 4 fed. Inside the steam turbine 4 the steam relaxes to a vapor pressure which is less than or equal to the rock pressure. Then, the so-relaxed steam through the injection pipe 2 into the deposit 9 of the oil sands are initiated. At the same time, the first generator G1 generates which output side on the shaft of the steam turbine 4 sits, electric power. The electric current is simultaneously used to operate the electric / electromagnetic heating 5 used, which also the deposit 9 of the oil sand heated. Heating of oil sand by means of steam and electric / electromagnetic heating 5 ensures a splitting of the long-chain hydrocarbons of the carbonaceous substances and for a reduction of the viscosity. Due to gravity, the bitumen-water emulsion seeps down. The bitumen-water emulsion is then transferred via the production pipeline 3 promoted to the earth's surface. For this purpose, an in 1 not shown lifting oil pump used. The bitumen-water emulsion passes from there to a treatment plant 8th , In this, on the one hand, the bitumen is separated from the water and then processed the bitumen to crude oil, on the other hand, the water through a corresponding line 10 back to the evaporator 1 led and can be evaporated again there. The proportion of water that is lost to the steam cycle during the process is supplied to the process again by fresh water or live steam. The evaporation in the evaporator 1 takes place by heating by means of an exhaust gas flow from the heat engine (gas turbine) 6 , The gas turbine 6 is connected to a second generator G2. The second generator G2 also generates electrical power which is used to operate the electrical / electromagnetic heating 5 is used.

The device according to the invention and the method according to the invention for obtaining carbonaceous substances, in particular bitumen from oil sands, are thus characterized by a particularly high level of efficiency. The heating of the deposit of oil sands takes place on the one hand with the help of hot steam in SAGD method and in addition via an electrical / electromagnetic heating (EMGD method). By the simultaneous use of the SAGD and EMGD process, a particularly good heating of the deposit takes place, which leads to a particularly good yield.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102012000092 [0006]
• DE 102007040605 [0007]

Claims (4)

Apparatus for recovering carbonaceous substances, in particular bitumen, from oil sands, comprising at least one steam generator ( 1 ), an injection pipeline ( 2 ) and a production pipeline ( 3 ), whereby via the injection pipeline ( 2 ) Steam can be introduced into the oil sands and via the production pipeline ( 3 ) the carbonaceous substances are dischargeable from the oil sand and wherein between the steam generator ( 1 ) and the injection pipeline ( 2 ) at least one steam turbine ( 4 ) is arranged, the output side is connected to a first generator (G1) for generating electricity, characterized in that the device is an electric / electromagnetic heating ( 5 ) for heating the oil sands operable with electric power generated by the first generator (G1). Apparatus according to claim 1, characterized in that the device at least one heat engine ( 6 ), in particular a gas turbine, which is connected on the output side with a second generator (G2) for generating electricity, and that the electric current which is generated by means of the second generator (G2) for simultaneous or alternative heating of the oil sands by means of the electric / electromagnetic heating ( 5 ) is usable. Apparatus according to claim 1 or 2, characterized in that the steam generation by means of heat exchangers ( 7 ), wherein the hot exhaust gas of the heat engine ( 6 ) is used for steam generation. Process for obtaining carbonaceous substances, in particular bitumen, from oil sands by means of a device according to claim 1, comprising the following process steps: - generating steam in the steam generator ( 1 ); - supplying the steam to the steam turbine ( 4 ); - Relaxation of the steam in the steam turbine ( 4 ) to a vapor pressure which is less than or equal to the rock pressure, - introduction of the vapor via the injection pipeline ( 2 ) in the oil sands; - food of the electric / electromagnetic heating ( 5 ) with electric current from the first and / or second generator (G1, G2); Heating the oil sand by means of steam and electrical / electromagnetic heating ( 5 ) and splitting the long-chain hydrocarbons of the carbonaceous substances; Discharging the carbonaceous substances via the production pipeline ( 3 ).

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