Carbon capture

Abstract

According to an example aspect of the present invention, there is provided a system for an industrial process, comprising a combustion apparatus configured to burn a fuel to convert water into steam at a first pressure, a mechanical device and / or chemical process, driven by the steam at the first pressure, configured to exhaust steam at a second pressure, and a carbon capture arrangement, driven by a pressurized fluid obtained in the system, configured to extract carbon dioxide from exhaust produced by the industrial process.

Description

CARBON CAPTUREFIELD

[0001] The present disclosure relates to carbon capture in industrial processes.BACKGROUND

[0002] Carbon dioxide, CO2, is one of the most relevant greenhouse gases driving man-made climate change, wherefore reducing the rate at which it is emitted into the atmosphere is of interest. The Earth receives energy from the sun, primarily in the form of visible light. Some of this energy is absorbed by the Earth's surface, warming it. The Earth then emits this energy back into space as infrared radiation (heat). CO2 is a greenhouse gas which absorb infrared radiation. Instead of allowing it to escape into space, it traps heat in the atmosphere. Thus, higher concentrations of CO2 in the atmosphere enhance the natural greenhouse effect, leading to more heat being trapped and contributing to global warming. Reducing the rate of CO2 emission may comprise using energy conversion processes, such as nuclear energy, which do not as such emit CO2, or employing fuels which emit less CO2 than others. For example, using natural gas emits less CO2 than using coal, per unit of energy obtained.

[0003] Another method to reduce rates of CO2 emission is carbon capture and storage, which seeks to remove at least a part of CO2 present in exhaust before releasing the exhaust into the atmosphere. The captured CO2 may be stored in a geological formation, for example, and / or its carbon may be processed into a solid-state compound. One of these methods applied in industry is absorption in which a solvent, such as an amine solution, is used to selectively absorb CO2 from a flue gas stream. In practice, absorption is carried out by directing the flue gases into an absorption column, wherein they come into contact with the solvent. The column may be designed to maximize the surface area for interaction, often using packing materials or trays. When flue gas passes through the column, CO2 molecules react with the solvent. For example, in the case of amine-based solvents, the CO2 forms a carbamate compound with the amine, effectively capturing the CO2. After absorption, the CO2-rich solvent is regenerated to release the captured CO2 so the solvent can be reused.This comprises that the CO2-rich solvent is heated in a unit, often called a stripper or regenerator. The increase in temperature reduces the solvent's affinity for CO2, causing the CO2 to be released. The released CO2 is then separated from the solvent, usually in a separate condenser.

[0004] In pulp mills black liquor is burnt to produce electricity and to recover the pulping chemicals used in digesting. Burning the black liquor releases CO2 along with other gases. Other CO2 release sources include lime kilns and power boilers.SUMMARY

[0005] According to some aspects, there is provided the subject-matter of the independent claims. Some embodiments are defined in the dependent claims.

[0006] According to a first aspect of the present disclosure, there is provided a system for an industrial process, comprising a combustion apparatus configured to burn a fuel to convert water into steam at a first pressure, a mechanical device and / or chemical process, driven by the steam at the first pressure, configured to exhaust steam at a second pressure, and a carbon capture arrangement, driven by a pressurized fluid obtained in the system, configured to extract carbon dioxide from exhaust produced by the industrial process.BRIEF DESCRIPTION OF THE DRAWINGS

[0007] FIGURE 1 illustrates an example pulp mill process in accordance with at least some embodiments of the present invention;

[0008] FIGURE 2A is an example carbon capture system in accordance with at least some embodiments of the present invention;

[0009] FIGURE 2B is an example carbon capture system in accordance with at least some embodiments of the present invention;

[0010] FIGURE 2C is an example carbon capture system in accordance with at least some embodiments of the present invention;

[0011] FIGURE 2D is an example carbon capture system in accordance with at least some embodiments of the present invention, and

[0012] FIGURE 3 illustrates an example industrial process in accordance with at least some embodiments of the present invention.EMBODIMENTS

[0013] By a carbon capture arrangement it is herein meant a carbon capture machine or system configured to run a carbon capture process, such as, for example, the amine scrubbing process or the potassium hydroxide based CO2 scrubbing process. Carbon capture as used herein refers to carbon capture and storage from flue gas generated in an industrial process where the carbon capture arrangement is run, rather than removal of CO2 from ambient air.

[0014] By industrial process it is herein meant an industrial facility, such as factory, power plant or processing site. Examples of industrial processes include pulp mills and biomass-based electricity generation plants which produce electricity by burning biomass.

[0015] By a pressurized fluid it is herein meant a fluid, such as water or steam, at a pressure in excess of atmospheric pressure. For example, water at a temperature of at least 60 degrees Celsius delivered via a pipe is a pressurized fluid as without pressure the water would not flow through the pipe.

[0016] Herein are disclosed systems where a carbon capture arrangement is driven by, that is, at least in part powered by, a pressurized fluid originating in the industrial process in which the carbon capture arrangement is located. For example, a pressurized fluid may be low-pressure steam from a turbine driven by high- pressure steam in the industrial process where the carbon capture takes place. In other words, energy used in generating the pressurized fluid is obtained in the industrial process where the carbon capture takes place. Technical benefits are thus obtained in terms of the carbon capture process being run without a need to draw on energy sources external to the industrial process which generates the flue gases which are subject to carbon capture.

[0017] FIGURE 1 illustrates an example pulp mill process in accordance with at least some embodiments of the present invention. FIGURE 1 illustrates schematically theoperation and organization of a pulp mill in accordance with at least some embodiments of the present invention. The example pulp mill is generally divided into a fibre line and a recovery line. In the fibre line, wood raw material is converted to pulp. In the recovery line, the cooking media and chemicals of the chemical cycle are treated and circulated. Further, energy contained in wood material is recovered.

[0018] The wood raw material may be softwood, for example pine or spruce, or hardwood, for example birch, although other raw-materials can be used as well. The process of the fibre line begins with peeling and chipping 2 of the wood, collecting the wood chips into piles 3, screening 4 of the wood chips, and then leading the screened chips to the digester 5. The bark obtained is dried 1 and then gasified for a lime kiln.

[0019] In the digester 5, the chips are delignified in alkaline white liquor in order to remove lignin while keeping the fibres as intact as possible. The delignified chips are washed and screened 6. Oxygen delignification 7 and bleaching steps 8 follow thereafter. The chemicals that may be used in the delignification and bleaching steps include MgSO4, sulphuric acid, hydrogen peroxide, oxygen, NaOH, and CIO2. Oxidized white liquor may be used in all or some of these steps. Sulphuric acid produced in the sulphuric acid plant 11 can be conducted to the bleaching step 8. The bleached pulp is dried 9, baled 10, and then delivered to the customers.

[0020] In the recovery line, the spent white liquor (black liquor) from the digester is led to an evaporation plant 12, from which the concentrated black liquor (heavy black liquor) goes to the recovery boiler 16 where it is burned. The recovery boiler generates solids (smelt), which are led to a regeneration cycle composed of a recausticizing unit 15 and a lime kiln 14. The smelt is mixed with weak white liquor to prepare so called green liquor, and treated in the recausticizing unit to produce white liquor, which contains the alkaline cooking chemicals and from which lime mud is separated. The lime kiln then burns the lime mud to burned lime for reuse. Lignin may be separated in unit 22 from the black liquor by acidification, for example by using sulphuric acid (for example from unit 11) and washed, then returning lignin wash liquids back to the evaporation 12.

[0021] Condensate from the evaporation plant 12 can be conducted to the bleaching step 8 and / or to a washing step of the oxygen delignification 7. Advantageously, part of the regenerated white liquor is not led to the digester 5 but to the oxygen delignification 7 and / or bleaching steps 8 to serve as a replacement of make-up NaOH. This side stream is oxidized.

[0022] The recovery boiler 16 also outputs fly ash and steam. Fly ash may be dumped, returned directly to the chemical cycle, or first treated to remove Cl and / or K and then returned to the chemical cycle. The hot steam produced in the recovery boiler 16 is mostly led to the turbine 17 to supply back-pressure steam and to generate electricity, which can be used by the mill itself or externally. Flue gases generated in the recovery boiler 16 and the lime kiln 14 may be filtered by means of electrical precipitators 19 and 18. Ash from the precipitator 19 is led both to the evaporator 12 and to an NPE removal system (25, here also referred to as “ARC”). The flue gases are conveyed through carbon capture arrangement 20 before release to the atmosphere. Flue gases from both precipitators 18 and 19 may be conveyed through carbon capture arrangement 20. In some embodiments, precipitators 18 and 19 are absent and flue gases are conveyed directly from recovery boiler 16 to carbon capture arrangement 20. Yet further, the flue gases may be cleaned using a process different from electrical precipitation before providing them to carbon capture arrangement 20. Carbon capture arrangement 20 is driven, either in part or entirely, by energy obtained from the pulp mill. In some embodiments, the process energy used in carbon capture arrangement 20 is obtained from the pulp mill, while control systems of the carbon capture arrangement may be powered by electric mains power.

[0023] Concentrated sulphur-containing odorous gases originating from the evaporation plant 12 or the digester 5 or the recausticizing 15 are led either to the recovery boiler 16, to the lime kiln 14, or to the sulphuric acid plant 11. GLSS (green liquor simplified stripping) products from the recausticizing unit 15 can be led to the sulphuric acid plant 11. The mill may include a biological wastewater treatment plant 21.

[0024] The CIO2 plant 24 uses NaCICh and sulphuric acid (from the sulphuric acid plant) among others as raw materials. The plant produces CIO2, which is led to the bleaching step 8, and waste acid, which contains sodium sulphate or sesquisulphate. The waste acid is led to the evaporation plant 12. The mill includes a tall oil plant 13. The tall oil plant receives tall oil soap from the cooking and / or evaporation plant 12 and sulphuric acid from the sulphuric acid plant 11. Mother liquor (brine) from the tall oil production process contains sulphur compounds. It is led back to the evaporation plant, which means that more sulphur is incorporated into the heavy black liquor and thereby into the chemical cycle.

[0025] In the specific example embodiment of FIG. 1, make-up sodium sulphate is input to the evaporator 12. If fly ash from another pulp mill is used as a sodium-containingmake-up chemical, it is preferable to input the fly ash directly to the ARC 25, because the ash may contain NPEs. Alternatively, the fly ash from another pulp mill can be input to the evaporator 12. Effluents from the ARC 25 are led to the biological wastewater treatment plant 21. Na and S containing waste from another pulp mill or from other external sources, such as metal industry or chemical industry, can be led to the ARC 25 or to the evaporator 12. Other embodiments do not comprise ARC 25.

[0026] Carbon capture processes, such as the amine scrubbing process, may either use pressurized steam in the process itself, or be powered using pressurized steam. The amine scrubbing process uses pressurized steam in the process itself wherefore it is advantageous to employ pressurized steam in carbon capture arrangement 20 which is obtained locally from an industrial process, of which the pulp mill of FIGURE 1 is an example. Other suitable industrial processes include electricity generation plants using power boilers.

[0027] FIGURE 2A is an example carbon capture system in accordance with at least some embodiments of the present invention. The carbon capture system is a system for an industrial process. An example of an industrial process is a pulp mill. In the system of FIGURE 2 A, recovery boiler 16 provides high-pressure steam to turbine 17 via conduit 210, causing turbine 17 to turn and drive an electrical generator, for example, or another application. At the same time, flue gas is conveyed from recovery boiler 16, via conduit 220, to carbon capture arrangement 20 for CO2 removal. The CO2 removal in carbon capture arrangement 20 is typically partial in that a part of, but not all of, the CO2 is removed from the flue gases before the flue gases are vented to the atmosphere via conduit 230. A recovery boiler is more generally an example of a combustion apparatus, which may in various embodiments be arranged to bum other fuels than black liquor, such as biofuels, such as pitch oil, odorous gases, methanol or turpentine, for example.

[0028] Carbon capture arrangement 20 is driven by low-pressure steam, obtained in carbon capture arrangement 20 via conduit 240 from turbine 17. This steam is low-pressure in the sense that is has lower pressure than high-pressure steam in conduit 210, used to dive turbine 17. For example, the low-pressure steam may have a pressure of between 3 barg and 4 barg, where barg refers to gauge pressure relative to ambient air pressure. The low- pressure steam in conduit 240 may originate in a condensing part of turbine 17, or at a stage of turbine 17 where the steam is prior to the condensing part. The latter option may be referred to as pre-condensing steam and its pressure is higher than that of stem harvestedfrom the condensing part of turbine 17. Either way, the steam in conduit 240 has a lower pressure than steam in conduit 210 and may thus be referred to as low-pressure steam. The pressurized steam from conduit 240 may be used directly in the amine scrubbing process, or to power another carbon capture process in carbon capture arrangement 20. The amine scrubbing process beneficially uses steam of 3 - 4 barg pressure, wherefore a useful synergy may be obtained when steam with a pressure in this range is obtained from e.g. turbine 17, enabling the driving of the carbon capture process without need for processing the steam to e.g. reduce or increase its pressure. The 3 - 4 barg pressure range is realistic to obtain from e.g. turbines in pulp mills.

[0029] In general, a mechanical device and / or chemical process may be driven by higher-pressure steam and emit lower-pressure steam after taking a part of the internal energy of the steam to drive its operation. An example of the mechanical device and / or chemical process is a turbine. The pressure at which steam is provided from recovery boiler 16 is a first pressure, and the pressure at which the steam is provided via conduit 240 is a second pressure. When turbine 17 uses a part of the internal energy of the steam at the first pressure, the second pressure is lower than the first pressure.

[0030] FIGURE 2B is an example carbon capture system in accordance with at least some embodiments of the present invention. The carbon capture system is a system for an industrial process. The system of FIGURE 2B resembles that of FIGURE 2A, and like numbering denotes like structure as in FIGURE 2A. In the system of FIGURE 2B, instead of conduit 240 from turbine 17, carbon capture arrangement 20 is driven by the high-pressure steam from recovery boiler 16. As noted above, in some embodiments a combustion apparatus other than a recovery boiler is used to generate the high-pressure steam. Alternatively to the illustrated arrangement, carbon capture arrangement 20 may receive the high-pressure steam from a conduit forked off conduit 210.

[0031] Compared to the solution in FIGURE 2A, that in FIGURE 2B has the property that the steam directly from recovery boiler 16 has higher temperature and pressure, which makes it possible to drive a further process with this steam before providing this steam to carbon capture arrangement 20. The further process would produce the benefit, that the steam would be reduced in pressure and temperature, making it more suitable to driving carbon capture using e.g. the amine scrubbing process. On the other hand, a part of the high- pressure steam is in this case consumed by carbon capture and the further process, leaving asmaller part of the energy output of recovery boiler 16 available to drive turbine 17, for example to produce electricity.

[0032] FIGURE 2C is an example carbon capture system in accordance with at least some embodiments of the present invention. The carbon capture system is a system for an industrial process. The system of FIGURE 2C resembles that of FIGURE 2B, and like numbering denotes like structure as in FIGURE 2B. In the system of FIGURE 2C, a biomass boiler 23, comprised in the system and separate from the recovery boiler 16 (or other combustion apparatus) is used to generate pressurized steam to drive carbon capture arrangement 20. This pressurized steam is delivered from biomass boiler 23 to carbon capture arrangement 20 via conduit 260, as illustrated. Biomass boiler 23 may burn wood bark, dead leaves or cardboard waste, for example. The pressure of the steam from biomass boiler 23 may be selected to be well suited to the carbon capture process in carbon capture arrangement 20, for example the amine scrubbing process.

[0033] FIGURE 2D is an example carbon capture system in accordance with at least some embodiments of the present invention. The carbon capture system is a system for an industrial process. The system of FIGURE 2D resembles that of FIGURE 2C, and like numbering denotes like structure as in FIGURE 2C. In the system of FIGURE 2D, water at a temperature of at least 60 degrees Celcius is conveyed via conduit 270 to a heat pump 26, which uses the heat in the water to obtain pressurised steam which is provided, via conduit 280, to carbon capture arrangement 20, which is driven by this pressurized steam, for example to drive the amine scrubbing or another carbon capture process on the flue gases obtained from recovery boiler 16, or another combustion apparatus, via conduit 220. The steam may be heated-up water from conduit 270, or the heat pump 26 may transfer heat from the water of conduit 270 to water from another water source to heat it into gaseous phase to obtain the steam.

[0034] The water obtained via conduit 270 is harvested from a source in the industrial process. For example, this water of at least 60 °C temperature may be from a bleaching plant in the industrial process, or the water may be warmed-up cooling water from cooling water channels of a machine in the industrial process, such that the warming of the water takes place as the industrial process runs. The water in conduit 270 may alternatively be condensate from evaporation plant 12. In some embodiments the water may be of at least 60 °C, 65 °C, 70°C or 80°C. The temperature of the water may be, depending on theembodiment, at most 150°C, 160°C, 180°C or 190°C. For example, the temperature may be between 60 - 190°C, between 60 - 180°C, between 60 - 160, between 60 - 150°C, between 70 - 190°C, between 70 - 180°C, between 70 - 160, or between 70 - 150°C.

[0035] In addition to the alternatives discussed herein above in connection with FIGURES 2A - 2D, further possible sources of steam used to drive carbon capture arrangement 20 is steam from evaporation plant 12 of FIGURE 1. A yet further option is to obtain steam and / or hot water from a white liquor plant comprised in the industrial process to drive carbon capture arrangement 20, or to obtain steam to drive carbon capture arrangement 20.

[0036] In some embodiments, carbon capture arrangement 20 is driven by energy from more than one of the alternatives illustrated in FIGURES 2A - 2D, for example, carbon capture arrangement 20 may use the option of FIGURE 2 A and, as an option and depending on the availability of low-pressure steam from turbine 17, steam from biomass plant 23 as in FIGURE 2C or steam from heat pump 26 as in FIGURE 2D. For example, when turbine 17 is not running, it may not provide the low-pressure steam of FIGURE 2A, and in such a situation, carbon capture arrangement 20 may be driven by steam from a biomass plane 23, or with heat from water above 60 °C. As a further option, in case recovery boiler 16 or the combustion apparatus is not in operation, carbon capture arrangement 20 may be driven by steam from a biomass plant 23, or with heat from water above 60 °C. Yet further, more than one of the options of FIGURES 2A - 2D may be used simultaneously, such as, for example the solution of FIGURES 2A simultaneously with FIGURE 2C and / or 2D.

[0037] In general, while described herein above in terms of a turbine 17, in some embodiments the industrial system comprises a mechanical device or chemical process which is driven by steam from the combustion apparatus. The mechanical device or chemical process may comprise, for example, the turbine 17 or, alternatively or in addition, a heat exchanger configured to drive a district heat network. A further example of a mechanical device that the steam from the combustion apparatus may drive is a crushing mechanism configured to process ore to a finer granular form. The mechanical device or chemical process may be configured to exhaust steam at a pressure which is lower than the pressure at which the mechanical device or chemical process received steam from the combustion apparatus, such a recovery boiler 16. Also the temperature of the steam is reduced in the mechanical device or chemical process compared to the temperature at which mechanicaldevice or chemical process received steam from the combustion apparatus, such a recovery boiler 16.

[0038] The system may be configured to select the pressurized fluid to drive the carbon capture arrangement based at least in part on an operating parameter of the industrial process. The operating parameter may comprise, for example, outside temperature, wind speed or a quantity of energy stored in a thermal energy storage. For example, the system may be configured to, when outside temperature is below a temperature threshold, drive carbon capture arrangement 20 using the pressurized steam from turbine 17 only, so that heat from biomass boiler 23 may be used for heating a building housing the industrial process, or for district heating, and when the outside temperature is in excess of the temperature threshold, to use both the pressurized steam from turbine 17 and steam from biomass boiler 23 to drive carbon capture arrangement 20. In this arrangement, is may be accepted that carbon capture is run less efficiently when it is cold outside. Likewise, when wind speed is in excess of a wind speed threshold, carbon capture arrangement 20 may be driven using pressurized steam from turbine 17 only, and when wind speed is below the wind speed threshold, both the pressurized steam from turbine 17 and steam from biomass boiler 23 may be used to drive carbon capture arrangement 20.

[0039] CO2 generated in pulp mills is biogenic CO2, which is a valuable raw material for use in e.g. renewable fuels. In general, biogenic CO2 is defined as CO2 originating in a natural carbon cycle, and combustion, digestion, fermentation or decomposition of biologically-based materials. Also CO2 generated in power boilers fuelled by renewable fuels is biogenic CO2. Fossil fuels have zero radiocarbon, 14C, whereas biogenic materials are enriched in14C. The amount of14C in biogenetic materials reflect the14C amount in atmosphere.14C has a half-life of 5 730 years and thus fossil fuels do not exhibit any14C.

[0040] FIGURE 3 illustrates an example industrial process in accordance with at least some embodiments of the present invention. A combustion apparatus 410, such as, for example, a recovery boiler or power boiler, bums a fuel and generates flue gas and heat, which is used to generate heat. In FIGURE 3, cooling water is provided from cooling tower 490 and / or a cooling cycle or coolers to combustion apparatus 410 via cooling conduits 4100 A. This water may be turned into pressurized steam using the heat released from the burned fuel, which as described herein above may comprise a biofuel.

[0041] The pressurized steam from combustion apparatus 410 is led via conduit 412 to turbine 420, which drive turbine 420 which in turn drives generator G to produce electricity to electricity grid 450. Turbine 420 generates, during operation, medium-pressure steam fractions 422, 424 from stages of the turbine, and low-pressure steam 426. While the excess of low-pressure steam 416 is condensed, some may be used, as described herein above, to drive one or more carbon capture arrangement 430, 435. Some of the low-pressure steam may also be used to drive another energy consuming process 440. Medium-pressure steam may be reduced in pressure to obtain e.g. steam of 3 - 4 barg pressure for use in an amine scrubbing carbon capture process.

[0042] Alternatively to the low-pressure steam 426, in some embodiments the high- pressure steam from combustion apparatus 410 may be used to drive the carbon capture arrangements 430, 435, via bypass 428 which provides the steam from combustion apparatus 410 bypassing turbine 420. This steam may also be used to drive the other energy consuming process 440. Steam is provided to carbon capture arrangements 430, 435 via steam conduits 42 A, 42B, respectively.

[0043] Further, and also as described herein above, carbon capture arrangements 430, 435 may be powered using water from cooling tower 490 and / or a cooling cycle or coolers or fresh water 4100. Hot water tank 460 is maintained hot using steam 470 originating in combustion apparatus 410 and secondary heat from a pulping process and, optionally, carbon capture units 430, 435. Heated water 41A may also be delivered directly from combustion apparatus 410 to hot water tank 460. Overflow hot water is relieved from hot water tank 460 via lead 46A, and new water is admitted to the system via water inlet 4100.

[0044] FIGURE 3 illustrates plural carbon capture arrangements 430, 435, which may be used to enable processing a large flow of flue gas, it being possible difficult to provide a single carbon capture arrangement with sufficient capacity to handle e.g. all the flue gas generated in combustion apparatus 410. Flue gases may also be produced in the industrial process in more than one place, for example in combustion apparatus 410 and a separate biomass boiler.

[0045] It is to be understood that the embodiments of the invention disclosed are not limited to the particular structures, process steps, or materials disclosed herein, but are extended to equivalents thereof as would be recognized by those ordinarily skilled in the relevant arts. It should also be understood that terminology employed herein is used for thepurpose of describing particular embodiments only and is not intended to be limiting.

[0046] Reference throughout this specification to one embodiment or an embodiment means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, appearances of the phrases “in one embodiment” or “in an embodiment” in various places throughout this specification are not necessarily all referring to the same embodiment. Where reference is made to a numerical value using a term such as, for example, about or substantially, the exact numerical value is also disclosed.

[0047] As used herein, a plurality of items, structural elements, compositional elements, and / or materials may be presented in a common list for convenience. However, these lists should be construed as though each member of the list is individually identified as a separate and unique member. Thus, no individual member of such list should be construed as a de facto equivalent of any other member of the same list solely based on their presentation in a common group without indications to the contrary. In addition, various embodiments and example of the present invention may be referred to herein along with alternatives for the various components thereof. It is understood that such embodiments, examples, and alternatives are not to be construed as de facto equivalents of one another, but are to be considered as separate and autonomous representations of the present invention.

[0048] Furthermore, the described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. In the preceding description, numerous specific details are provided, such as examples of lengths, widths, shapes, etc., to provide a thorough understanding of embodiments of the invention. One skilled in the relevant art will recognize, however, that the invention can be practiced without one or more of the specific details, or with other methods, components, materials, etc. In other instances, well-known structures, materials, or operations are not shown or described in detail to avoid obscuring aspects of the invention.

[0049] While the forgoing examples are illustrative of the principles of the present invention in one or more particular applications, it will be apparent to those of ordinary skill in the art that numerous modifications in form, usage and details of implementation can be made without the exercise of inventive faculty, and without departing from the principles and concepts of the invention. Accordingly, it is not intended that the invention be limited, except as by the claims set forth below.

[0050] The verbs “to comprise” and “to include” are used in this document as open limitations that neither exclude nor require the existence of also un-recited features. The features recited in depending claims are mutually freely combinable unless otherwise explicitly stated. Furthermore, it is to be understood that the use of "a" or "an", that is, a singular form, throughout this document does not exclude a plurality.

[0051] As used herein, “at least one of the following: ” and “at least one of ” and similar wording, where the list of two or more elements are joined by “and” or “or”, mean at least any one of the elements, or at least any two or more of the elements, or at least all the elements. INDUSTRIAL APPLICABILITY

[0052] At least some embodiments of the present invention find industrial application in carbon capture and storage.ACRONYMS LISTCO2 carbon dioxide NPE non-processed elements

Claims

CLAIMS:

1. A system for an industrial process, comprising:- a combustion apparatus configured to burn a fuel to convert water into steam at a first pressure;- a mechanical device and / or chemical process, driven by the steam at the first pressure, configured to exhaust steam at a second pressure, and- a carbon capture arrangement, driven by a pressurized fluid obtained in the system, configured to extract carbon dioxide from exhaust produced by the industrial process.

2. The system according to claim 1, wherein the pressurized fluid comprises one of the following:- the steam at the second pressure from the mechanical device and / or chemical process;- the steam at the first pressure from the combustion apparatus;- steam from a biomass boiler, comprised in the system and separate from the combustion apparatus;- water having a temperature of at least 60 degrees Celsius from the industrial process;- steam from an evaporation plant comprised in the system;- condensate from the evaporation plant comprised in the system;3. The system according to claim 2, wherein the pressurized fluid is the steam at the second pressure from the mechanical device, the mechanical device being a turbine, wherein the steam at the second pressure from the turbine comprises either steam from a condensing part of the turbine, or steam from a pre-condensing part of the turbine.

4. The system according to any of claims 1 - 3, wherein the industrial process is a pulp mill, the combustion apparatus is a recovery boiler or a power boiler using a biofuel as the fuel.

5. The system according to claim 4, wherein the biofuel comprises one or more of black liquor, pitch oil, odorous gases, methanol or turpentine.

6. The system according to any of claims 1 - 5, configured to select the pressurized fluid to drive the carbon capture arrangement based at least in part on an operating parameter of the industrial process.

7. The system according to any of claims 1 - 6, wherein the carbon capture arrangement is configured to employ an amine scrubbing process to extract the carbon dioxide from the exhaust.

8. The system according to any of claims 1 - 7, wherein the second pressure is lower than the first pressure.

Images