WO2012126591A1

WO2012126591A1 - Method for the energy-efficient and environmentally friendly obtention of light oil and/or fuels on the basis of crude bitumen from oil shales and/or oil sands

Info

Publication number: WO2012126591A1
Application number: PCT/EP2012/001168
Authority: WO
Inventors: Thomas Stumpf; Ulf Boenkendorf; Leonhard Baumann; Roland Möller
Original assignee: Ecoloop Gmbh
Priority date: 2011-03-18
Filing date: 2012-03-16
Publication date: 2012-09-27
Also published as: RU2013146371A; US20140008272A1; CN103547657A; RU2576250C2; EP2686403A1; DE102011014345A1; CA2830454A1

Abstract

The present invention relates to a method for the energy-efficient and environmentally friendly obtention of light oil and/or fuels on the basis of crude bitumen from oil shales and/or oil sands (1) by thermal use of carbonaceous residues which are obtained during this process, whereby the carbonaceous residues are converted at temperatures below 1800 °C into sulfur-poor, gaseous cleavage products (31) by sub-stoichiometric oxidation with oxygen-containing gas in an updraft gasifier (19) which is operated with a bulk material moving bed while alkaline substances are added. The cleavage products are then converted into sensible heat by hyperstoichiometric oxidation and are used for the production of heated aqueous process media (2) for physically comminuting the oil sands and/or oil shales (1) and/or for separating of the crude bitumen (7) from the rock material and/or as process heat for the thermal fractioning (12) of the crude bitumen (7).

Description

Process for the energy-efficient and environmentally friendly production of light oils and / or fuels from crude oil slate and / or oil sands

The present invention is concerned with a method for energy-efficient and environmentally friendly recovery of light oil and / or fuels from raw bitumen from oil shale and / or oil sands by thermal utilization of resulting in this extraction carbon-containing compounds.

Due to the strong global demand for fossil fuels and oil-based raw materials, as well as the long-term expected shortage of conventional oil reserves, the extraction of energy sources and raw materials from oil shale and / or oil sands deposits is becoming increasingly important.

Naturally occurring oil sands or oil shales are made from natural rock and contain up to 20% of a bitumen mixture. This bitumen mixture contains essentially organic carbon compounds of different molecular weights and boiling points.

State of the art:

In order to make these carbon compounds accessible for targeted extraction, the bitumen mixture must first be separated from the fraction of earth rock.

The separation of the bitumen from these masses of rock can essentially be done using two technologies.

CONFIRMATION COPY Extraction in the open pit:

In this method, the bitumen-containing rock mass is removed with excavators or wheel loaders and transported by heavy-duty vehicles to the treatment plants. The preparation usually takes place in the following process steps:

1. breaking / crushing of the rock usually with supply of steam or hot water

2. transfer of the resulting suspension in the

first extraction step, where sediment and water forms as the lower separation layer, and bitumen with foam as the upper separation layer.

3. Removal of the lower sediment and water layer in mostly artificial reservoirs or water lagoons

4. removal of the upper bituminous layer in the second extraction step, where residues of water and fine particles are separated. The bitumen is usually dissolved in an organic solvent (usually "naphtha", which is a product of the light oil recovery process) to give the so-called raw bitumen.

5. The raw bitumen is transferred to a subsequent bitumen preparation ("upgrading").

Extraction via the so-called "in-situ method":

With this technology, the raw bitumen is already recovered in the soil, below the surface of the earth and without breaking down the rock masses. This is done as follows: 6. High-pressure water vapor is injected into deep bitumen-containing rock layers. As a result, a thermal liquefaction of the raw bitumen is achieved.

7. This liquefied raw bitumen is directed to subterranean collection points and conveyed from there by means of suitable pump-conveyor technology to the earth's surface.

8. The raw bitumen thus obtained usually follows the further course of action according to the above-mentioned. Point 5.

Production of light oil and liquid fuels from raw bitumen:

The raw bitumen is (if applicable from both extraction methods) brought together in the next processing plant ("upgrading"), where the following process steps are usually carried out:

9. From the mixture consisting of crude bitumen and naphtha, the volatile hydrocarbons are distilled off. In the end, there remains an insoluble residue, the so-called pet coke. Depending on the feedstock, this may contain up to 10% spilled portions.

10. The gaseous hydrocarbons from the distillation are separated by fractional condensation in naphtha, kerosene and gas oil, with naphtha is usually at least partially recycled to the process.

11. Depending on the quality requirements for the individual fractions, a desulfurization may be carried out in the further step. This is usually done by means of hydrogenation and separation of elemental sulfur.

12. At the end of the process is the storage and removal of the liquid fractions.

However, the process described above for obtaining light oil and fuels from oil shale and / or oil sands has considerable disadvantages.

Thus, the extraction of the raw bitumen from the rock masses requires significant amounts of hot water and water vapor. For each unit of light oil produced, up to 6 volumes of water must be used. The preparation of steam and hot water is usually in boilers with natural gas firing. The demand for natural gas is extremely high and leads to an extremely unfavorable energy balance of the overall process. Furthermore, as a result, the specific C0 ₂ emissions per barrel of light oil obtained are fundamentally ecological and unacceptable in terms of the necessary protection of valuable resources.

The in the distillation of the raw bitumen (step

9.) Residual pet coke contains sulfur in concentrations of up to 10%. This is basically a valuable source of energy. However, this can not readily be used in combustion processes, for example for the production of steam or hot water due to its high sulfur content. The guarantee of environmentally sound, thermal utilization is therefore questionable and if at all possible only with disproportionate effort for a flue gas desulfurization. For the present invention, therefore, the task has been found to provide a method that does not have the disadvantages of the prior art, but that allows energy-efficient utilization of Kohlenstoffträgem, contained in oil sands and / or oil shale, which protects fossil resources (eg natural gas) and that can generate sufficient sources of energy on its own initiative in order to at least partially supply the recycling process with the necessary own energy requirements.

This is inventively achieved in that the carbonaceous compounds contain sulfur and converted by low-stoichiometric oxidation with oxygen-containing gas in a operated with a bulk material bed countercurrent carburetor with the addition of alkaline substances at temperatures <1800 ° C in low-sulfur gaseous fission products and these cleavage products then converted into sensible heat by superstoichiometric oxidation and used to produce heated aqueous process media for physical comminution of the oil sands and / or oil shale and / or separation of the raw bitumen from the rock mass and / or as process heat for thermal fractionation of the raw bitumen.

It has been shown that the residues, which have not yet been utilized due to the sulfur problem, can considerably improve the energy balance in the production of light oil and / or fuels from oil shale and / or oil sands. The meaningful utilization of the carbon constituents also eliminates the environmental hazard of carbon compounds remaining in the residual materials.

For example, as carbonaceous compounds, solid residues from the aqueous separation of raw gymnastics of the rock mass and / or solid residues from the thermal fractionation of the raw bitumen.

Particularly advantageous is a development of the method in which the countercurrent carburetor as a vertical process chamber with a calcination zone and an oxidation zone in which the calcined carbon and sulfur-containing residues oxidize with oxygen-containing gas, wherein the gaseous reaction products are withdrawn at the top of the vertical reaction space, in is formed in the form of a vertical shaft furnace, which is continuously flowed through from a bulk material, which itself is not oxidized from top to bottom, and the oxygen-containing gas is at least partially introduced below the oxidation zone, whereby the ascending gas flow is promoted. The advantage of an inert bulk material is that the mechanical properties of the bed can be influenced more easily and adapted to the process-essential aspects.

Examples of usable alkaline substances are metal oxides, metal carbonates, metal hydroxides or mixtures thereof, which metered into the gas phase above the calcining zone

and / or admixed with the carbonaceous and sulfur-containing residues before entering the vertical process space. Particular preference is given to elements of the alkali metals or elements of the alkaline earth metals, in particular calcium, for forming the metal oxides, carbonates or hydroxides, since, in particular in the form of calcium oxide, catalytic effects have a positive influence on the process sequences.

A clogging of the alkaline substances at least partially in fine-grained form with a particle size of <2 mm has proved to be advantageous, as well as a substoichiometric oxidation at a Λ of <0.5, particularly preferably of <0.3. The sulfur linkage mechanisms run particularly favorably by the addition of alkaline substances under reductive Bedin ^¬ conditions, the countercurrent gasifier at temperatures of the resulting above 400 ° C from the constituents of the carbon material and sulfur-containing residues gaseous sulfur compounds by chemical reaction with the alkaline substances converted into solid sulfur compounds, these solid sulfur compounds are at least partially discharged with the gaseous reaction products and removed at temperatures above 300 ° C from the gas phase by fines separation. In this way, the sulfur can escape the process in a particularly economical manner.

In a desired procedure in the vertical process chamber and / or in the gas phase of the withdrawn gaseous reaction products in the presence of water vapor and calcium oxide and / or calcium carbonate and / or calcium hydroxide, a calcium-catalyzed reforming of significant proportions of the resulting oil and / or tar-containing fission products, which have a chain length of> C4, to carbon monoxide, carbon dioxide and hydrogen at temperatures of above 400 ° C carried out.

The bulk material moving bed is preferably formed by additional metering of coarse material in order to increase the flowability of the bulk material and / or its gas permeability, wherein the coarse material is the carbonaceous compounds before entering the vertical process space anschaubsicht. The coarse material may minerals and / or other inorganic substances, eg. B. mixtures with a particle size in the range of 2 mm to 300 mm or directly in the form of oil sands

and / or oil shale are used. The latter case is particularly preferred because it allows a procedure to be carried out. light is where local resources can be used and exploited immediately.

Also advantageous may be the use of wood and / or other biogenic materials as coarse material with a corresponding grain size. Often, these materials are found near the process sites, so their utilization benefits the energy efficiency of the overall balance due to short transport distances.

Inert bulk material can be separated from contained fines and ashes at the lower end of the vertical process space and at least partially returned to the process as coarse material, so that the travel distances for the masses to be moved can be kept low. It may also be advantageous to convert the carbonaceous compounds by agglomeration into particles having a particle size in the range between 2 mm and 300 mm prior to use in the countercurrent gasifier, in order, as in the case of the additional metering of coarse material, to allow the bulk material to flow and / or to improve its gas permeability.

For the gas countercurrent, the formation of a differential pressure in a range of 50 to 1000 mbar (g) in the vertical process space between the top and the bottom has proven to be advantageous.

FIG. 1 shows an example of an integrated process for producing light oil and fuels by mining the oil sands or oil shale in opencast mining.

The oil sands or oil shale (A) obtained in open-pit mining are mechanically crushed by crushers (1). This is usually done by adding hot water or else Water vapor (2). Hot water / steam is used in boiler systems

(3) generated.

The resulting in mechanical comminution suspension is fed to a first extraction stage (4). Here, hot water / steam (5) is usually fed again. After intensive mixing is in the extraction stage

(4) carried out by settling a separation of the phases. The lower phase forms a water / sediment phase (B). This is separated and spent mostly in artificially created lagoons or lakes (6).

The upper phase (7) essentially contains Ron bitumen. This is separated and fed to the subsequent process step (C).

In the first extraction stage usually still forms a middle phase (8), which can also contain significant amounts of raw bitumen in addition to water / sediment. This middle phase can be fed to a second extraction stage (9). Here, a second separation is performed, with the lower water / sediment phase (D) being separated and also being spent in man-made lagoons or lakes (6). The upper phase (10) essentially contains raw bitumen and is likewise fed to the subsequent process stage (C.).

In process step (C), the crude bitumen can be mixed with organic solvents, for example with naphtha (11), which is obtained as a product during the later bitumen refining. Depending on the quality of bitumen, undissolved residues (E), also known as pet coke, can be produced. The dissolved crude bitumen is fed to a distillation (12), where the vaporizable fractions are evaporated by supplying heat by means of superheated steam (13) from the boiler plants and using suitable distillation apparatuses, leaving behind as non-vaporizable fraction of other pet coke (E). These are carbon-rich residues that have a high calorific value, but can contain up to 10% sulfur.

The vaporizable fractions (14) are separated, for example, via fractional condensation (15) into various boiling fractions, which may consist of, among others, light oil (16), naphtha (11), and various fuels (17).

The process described is very energy-intensive, since very large amounts of hot water / steam in boiler systems (3) must be generated. For this purpose, significant amounts of fossil fuels, especially natural gas (18) have been used.

The inventive method provides to replace this natural gas wholly or partly with in a countercurrent gasifier (19) generated synthesis gas (20) and this synthesis gas as

To use fuel in the boiler plants (3).

The generation of the synthesis gas is carried out by gasification of carbonaceous materials in a countercurrent gasifier (19), which is designed as a vertical process space. This process space is flowed through by a bulk material (21) from top to bottom. The bulk material may preferably consist of coarse-grained material, whereby the use of sediment (B) and / or (D) is also suitable as bulk material. Particularly advantageously, the bulk material can also be partially formed from the oil sand / oil shale (A), in which case it is also advantageous may be to mechanically crush the material (A) before use as bulk material to ei ^¬ ne particle size of less than 20 cm. This bulk material can be added further residues from the process described above prior to entry into the countercurrent gasifier. In particular, this is the pet coke (E), which has a high calorific value due to its high carbon content. The mixture of bulk material and residues flows through the vertical process space (19) by its own gravity from top to bottom. The countercurrent carburettor has burner lances in the middle area

(22) for a base load firing in the vertical process space and for the stationary formation of a firing zone

(23). These burner lances can be operated with fossil fuels (24) and oxygen-containing gas (25). As an alternative to fossil fuels, synthesis gas from the countercurrent gasifier (20) or also the raw bitumen (C) dissolved in naphtha can be used.

Oxygen-containing gas (26) is introduced at the lower end of the vertical process space. This gas is initially used to cool the bulk material before leaving the vertical process space in a cooling zone (27). The oxygen-containing gas is preheated while it continues to flow upwards in the vertical process space. According to the countercurrent gasification principle, the oxygen from the oxygen-containing gas reacts with the carbonaceous materials in the bulk material by oxidation, wherein the amount of oxygen-containing gas is adjusted so that a total lambda of less than 0.5 is established in the vertical process space. This initially forms a combustion zone (23), react in the residues of the carbonaceous material with oxygen to CO ₂ . Further up, the oxygen continues to decrease, so that finally only carbonization to CO can take place, until still Finally, all the oxygen is consumed above and a pyrolysis zone (28) is formed.

If, conversely, the flow of the bulk material and of the carbonaceous materials is considered from top to bottom, then, in the pyrolysis zone (28), a drying of the usually moist feedstocks takes place initially up to an inherent temperature of 100.degree. Thereafter, the natural temperature of the materials continues to increase, so that the gasification process begins and at an autogenous temperature of up to 500 ° C, the formation of methane, hydrogen and CO begins. After extensive degassing, the autogenous temperature of the downwardly moving materials continues to increase due to the hot gases rising from the combustion zone (23), so that the carbon-rich materials are finally completely degassed and consist only of residual coke, the so-called pyrolysis coke, and ash fractions. The pyrolysis coke is transported further with the bulk material in the vertical process space down to where it is converted at temperatures above 800 ° C with the C0 ₂ -Anteilen from the combustion zone by Boudouard conversion partially in CO and also gasified. Part of the pyrolysis coke also reacts in this zone according to the water gas reaction with water vapor, which is also contained in the hot gases, to form CO and hydrogen. Residues of the pyrolysis coke are finally burned almost completely in the combustion zone (23) with the oxygen-containing gas flowing in from below at temperatures below 1800 ° C. and used thermally. This makes it possible that the countercurrent carburetor can supply almost completely with the necessary energy for gasification. This is also referred to as the autothermal gasification process. In the cooling zone and water (29) via water lances (30) can be metered as another cooling and gasifying agent.

The synthesis gas formed in the vertical process space is aspirated (31) at the upper end, so that in the upper gas space (32) preferably a slight negative pressure of 0 to - 200 mbar sets.

During the gasification process, depending on the quality of the feedstock, considerable amounts of gaseous sulfur compounds may be produced. Therefore, it is advantageous if the bulk material before mixing in the vertical process space alkaline substances (33) are admixed. In this case, metal oxides, metal hydroxides or metal carbonates are particularly suitable where the use of fine-grained calcium oxide is particularly preferred because it reacts spontaneously with its reactivity and large surface fertilize with the formed gaseous Schweielverbin and thereby forms solid sulfur compounds, which predominantly together with the aspirated Synthesega be discharged from the vertical process space. Furthermore, other pollutants, such as chlorine, hydrogen chloride or heavy metals can be very effectively bound to the CaO and discharged in the same way from the process who the.

In addition, it may be useful to use coarse-grained metal oxides, metal hydroxides or metal carbonates as bulk material in order to increase the bulk material in proportion to the carbonaceous materials and also alkaline reactants in the lower part of the vertical process space for the bonding of the gaseous Sulfur compounds to provide. The extracted synthesis gas contains dust, which consists essentially of the solid sulfur compounds, fine-grained alkaline substances, other pollutants and inert particles. This dust-containing synthesis gas can be treated in the gas space of the vertical process space or after leaving the vertical process space in the presence of steam and fine-grained calcium oxide at temperatures above 400 ° C. This temperature can be adjusted by appropriately adjusting the amount of oxygen-containing gas (26) at the bottom of the vertical process space or by the heat output of the burner lances (30) in the burning zone. However, it is particularly advantageous to use direct firing into the synthesis gas via burner lances (34) which are operated stoichiometrically with fuel and oxygen-containing gas or else with an excess of oxygen-containing gas. This thermal aftertreatment in the presence of water vapor and calcium oxide ensures the cleavage of oils and tars which are still present in small quantities in the synthesis gas by the catalytic action of the calcium oxide.

The dust-containing synthesis gas is then freed from the dust at temperatures above 300 ° C via a hot gas filtration (35). The sulfur-containing filter dust (36) is discharged from the process and sent for disposal or alternative use.

The resulting synthesis gas is virtually sulfur-free and can be used as fuel in the boiler plants (3). Depending on the site conditions or the requirements of the boiler systems, it may be necessary to cool the syngas with gas cooler (38) and to free it of condensates before it can be used in the boiler systems. The accumulating condensate (39) can be at least partially reused as cooling and gasifying agent over the water lances (30) in the vertical process space.

The combustion of the purified synthesis gas (20) allows the operation of the boiler systems, without a treatment of the flue gas (40) is required by a complex flue gas desulfurization.

The bulk material mixture (41) emerging at the lower end of the vertical reaction space contains essentially coarse-grained bulk material, residues of ash and fine-grained bulk material. The fine-grained bulk material may still contain small amounts of sulfur products and other pollutants.

The total bulk material flow can be deposited in total (42). However, particularly preferred is a screening of the bulk material mixture (43), wherein the coarse fraction (44) is preferably at least partially recirculated, and reused as bulk material in the vertical process space.

The fine sieve fraction (45) is discharged from the process together with the sulfur-containing filter dust (36) and sent for disposal or alternative use.

Figure 2 shows an example of an integrated process for the production of light oil and fuels, wherein the raw bitumen is obtained by the in situ underground method.

In the in situ method, the raw bitumen is not obtained by decomposition of the soil and its extraction, but liquefied by melting in the earth's crust and promoted over Pumpsys ^¬ teme to the surface. Here, in bitumen-containing soil (1) by means of special lance systems (2) high-pressure steam from the boiler plant (3) is injected. As a result, the bitumen is liquefied (4) and discharged into underground collection points (5). From there, the liquid raw bitumen is conveyed via risers (6) and special conveyor systems (7) for days. This liquid raw bitumen is then used in the subsequent process stage C.

Another technology involves the use of special burner lances (8), which initiate partial combustion of the raw bitumen in the earth's crust. This can be done, for example, by superstoichiometric combustion of fossil fuels (9) with oxygen-containing gas (10), whereby the excess of oxygen-containing gas (10) causes partial combustion of the raw bitumen in the soil and thereby provides energy for the liquefaction of the raw bitumen becomes.

According to the invention, the required high-pressure steam in the boiler plants (3) with synthesis gas (20) can also be generated as fuel in this example. Furthermore, syngas can also be used as fuel for the partial combustion via the special burner systems (8).

Often the in-situ method is also combined with the opencast mine according to FIG. In both cases, raw bitumen is recovered, which is then combined in process stage (C) and further refined.

The further course of the process from the process stage (C) is analogous to the description according to FIG. 1.

Claims

claims

Process for the energy-efficient and environmentally friendly production of light oils and / or fuels from crude bitumen from oil shale and / or oil sands (A) by thermal utilization of carbon-containing compounds (E) obtained in this production, characterized in that the carbon-containing compounds contain sulfur and by substoichiometric oxidation with oxygen-containing gas (26) converted into low-sulfur gaseous fission products at temperatures <1800 ° C. in a countercurrent gasifier (19) operated with a bulk material moving bed (21), and these fission products are then converted into sensible by super-stoichiometric oxidation Converted heat, and for generating heated aqueous process media for physical comminution of the oil sands and / or oil shale (A) and / or for separating the raw bitumen from the rock mass and / or as process heat for a thermal fractionation d it raw bitumens are used.

A method according to claim 1, characterized in that are used as carbonaceous compounds solid residues from the aqueous separation of crude bitumen from the rock mass and / or solid residues from the thermal fractionation of the crude bitumen.

Method according to one of the preceding claims, characterized in that the countercurrent carburetor (19) as vertical process space with a calcination zone and an oxidation zone (23) in which the calcined carbon and sulfur containing residues (E) oxidize with oxygenous gas (26), the gaseous reaction products being withdrawn at the top of the vertical reaction space, the vertical process space in the Form of a vertical shaft furnace is formed, which is continuously flowed through from a bulk material (21), which itself is not oxidized from top to bottom, and the oxygen-containing gas (26) is at least partially introduced below the oxidation zone (23), whereby the ascending Gas flow is promoted.

Method according to one of the preceding claims, characterized in that as alkaline substances metal oxides, metal carbonates, metal hydroxides or mixtures of two or three of these substances used, and metered specifically in the vertical process space (19) and / or in the gas phase above the calcination, and / or admixed with the carbonaceous compounds before entering the vertical process space.

A method according to claim 4, characterized in that the metal oxides, metal carbonates and metal hydroxides contain elements of the alkali metals or elements of the alkaline earth metals and particularly preferably calcium as a cation.

Method according to one of the preceding claims, characterized in that the alkaline substances at least partially used in fine-grained form with a particle size of less than 2 mm.

7. The method according to any one of the preceding claims, characterized in that the substoichiometric oxidation is carried out at a lambda of less than 0.5 and more preferably of less than 0.3.

8. The method according to any one of the preceding claims, characterized in that the addition of alkaline substances under reductive conditions, the countercurrent gasifier (19) at temperatures of above 400 ° C from the components of the carbon and sulfur-containing residues resulting gaseous sulfur compounds converted by chemical reaction with the alkaline substances in solid sulfur compounds, these solid sulfur compounds are at least partially discharged with the gaseous reaction products, and removed at temperatures above 300 ° C from the gas phase by fines separation.

9. The method according to any one of the preceding claims, characterized in that in the vertical process chamber (19) and / or in the gas phase of the withdrawn gaseous reaction products in the presence of water vapor and calcium oxide and / or calcium carbonate and / or calcium hydroxide, a calcium catalyzed reforming of substantial proportions of the resulting oil and / or tar-containing cleavage products which have a chain length of greater than C4, to carbon monoxide, carbon dioxide and hydrogen at temperatures above 400 ° C uui is led hui.

10. The method according to any one of the preceding claims, characterized in that the bulk material moving bed (21) part ^{¬ is formed} by additional dosage of coarse material to increase the flowability of the bulk material and / or its gas permeability, wherein the coarse material, the carbon-containing compounds before entering the vertical process space.

11. The method according to claim 10, characterized in that are used as coarse minerals and / or other inorganic substances or mixtures with a particle size in the range of 2 mm to 300 mm and more preferably oil sands and / or oil shale.

12. The method according to claim 10, characterized

wood and / or other biogenic materials having a particle size in the range from 2 mm to 300 mm are used as coarse material.

13. The method according to claim 10, characterized

that the coarse material at the lower end of the vertical process space is separated from contained fines and ashes and at least partially returned to the process as coarse material.

14. The method according to any one of the preceding claims, characterized in that the carbon-containing compounds are thinned before use in the countercurrent gasifier by agglomeration into particles having a particle size in the range between 2 mm and 300 mm. Method according to one of the preceding claims, characterized in that in the vertical process space between the top and the bottom of a differential pressure; in a range of 50 to 1000 mbar (ü) is formed.