Method and system for storing carbon dioxide in industrial waste suspensions

Abstract

The present invention relates to a method and system for storing carbon dioxide in an industrial waste suspension. A method for storing carbon dioxide in an industrial waste suspension (1) comprising the steps of: a. providing a collection container (2) containing said industrial waste suspension (1); b. supplying a volumetric flow rate of a carbon dioxide-containing gas (9) to the industrial waste suspension (1) so that the industrial waste suspension (1) is enriched with carbon dioxide and at least a portion of the carbon dioxide is mineralized in the industrial waste suspension; c. Measuring the loss of carbon dioxide from the carbon dioxide-enriched industrial waste suspension; d. measuring the amount of mineralized carbon dioxide based on the amount of carbon dioxide supplied and the amount of carbon dioxide lost.

Description

[Technical Field]

[0001] The present invention relates to a method and system for storing carbon dioxide in an industrial waste suspension. [Background technology]

[0002] In the Paris Climate Agreement, participating countries agreed to limit the increase in global average temperature to well below 2°C, with efforts to limit it to 1.5°C. This means that greenhouse gas emissions must be reduced to net zero by 2050. To achieve this goal, storage solutions are needed for the unavoidable carbon dioxide emissions from industrial processes. Storage options should enable the global storage of more than 10 Gt of carbon dioxide per year by 2050. Summary of the Invention

[0003] The present invention is directed to the use of industrial waste suspensions as carbon dioxide storage media. Typical industrial waste suspensions are aqueous. Examples of industrial waste suspensions include, for example, sludge obtained from cleaning concrete mixing plants and sludge obtained from washing sand and / or gravel. Other examples of industrial waste suspensions include slag obtained from iron or steel production (e.g., blast furnace slag, electric arc furnace slag, and / or basic oxygen furnace slag). Furthermore, sludges and slags containing ash (e.g., waste incineration ash, sewage sludge ash, wood ash, paper incineration ash, and / or coal ash) can also be used. Additionally, sludges and slags containing dust (e.g., cement bypass dust and / or cement kiln dust) can also be used.

[0004] The present invention relates to a method for storing carbon dioxide in an industrial waste suspension. The method includes the following steps: In step (a), a collection vessel containing an industrial waste suspension is provided; In step (b), a volumetric flow rate of a carbon dioxide-containing gas (hereinafter also referred to as "feed gas") is supplied to the industrial waste suspension so that the industrial waste suspension is enriched with carbon dioxide (i.e., a "carbon dioxide-enriched industrial waste suspension" is formed); In this way, at least a portion of the carbon dioxide is mineralized in the industrial waste suspension (i.e., a mineralized carbon dioxide-containing industrial waste suspension is formed); In step (c), the amount of carbon dioxide loss from the industrial waste suspension enriched with carbon dioxide is measured; and In step (d), the amount of mineralized carbon dioxide is measured based on the amount of carbon dioxide supplied and the amount of carbon dioxide loss in the (carbon dioxide-containing) gas volumetric flow rate. Here, steps (b) and (c), particularly steps (b) to (d), can be performed continuously or repeatedly. Preferably, the method is performed continuously or repeatedly until an end criterion is reached.

[0005] The industrial waste suspension preferably has an initial pH value that allows for carbon dioxide mineralization. In some embodiments, the initial pH value may be greater than 6. However, the initial pH value is preferably greater than 9, and more preferably greater than 12. Depending on the application, the industrial waste suspension may be, for example, concrete wash water.

[0006] In some embodiments, the industrial waste suspension comprises or consists of an aqueous solution and a solid cement mineral. As such, the water in the aqueous solution may be in phase equilibrium with the solid cement mineral. In some embodiments, the industrial waste suspension may include calcium ions at least partially dissolved in the aqueous solution.

[0007] In the context of this application, carbon dioxide mineralization refers to the chemical reaction of carbon dioxide, for example, via reaction with suspended cement minerals and / or hydroxyl ions in the industrial waste suspension. The mineralization of carbon dioxide results in the formation of a precipitate containing carbonates and / or bicarbonates. The precipitate may preferably contain calcium, and in particular may be at least partially calcium carbonate. The precipitation of calcium carbonate causes the aqueous solution of the industrial waste suspension to become undersaturated, resulting in further dissolution of calcium ions into the aqueous solution (until the saturation limit is again reached). The newly dissolved calcium ions then again make further carbon dioxide mineralization possible. Therefore, in order to store as much carbon dioxide as possible in the industrial waste suspension, mineralization must be carried out continuously or repeatedly until no more calcium ions are dissolved.

[0008] Depending on the application, measuring the amount of carbon dioxide loss may include monitoring the excess gas emitted from the carbon dioxide-enriched industrial waste suspension. Monitoring the excess gas may be understood to mean monitoring whether excess gas is being emitted. If excess gas is not being emitted, the amount of carbon dioxide loss (at that time) is zero. Monitoring the excess gas may include measuring the carbon dioxide concentration in the excess gas and / or measuring the volumetric flow rate of the excess gas. From both measurements, the amount of carbon dioxide loss (i.e., the amount of carbon dioxide that has not been mineralized) can be calculated. Both measurements may be zero, in which case the amount of carbon dioxide loss is zero. If the feed gas is composed of 100% carbon dioxide, it is sufficient to only measure the volumetric flow rate of the excess gas. Depending on the application, the method may include separating the emitted excess gas from the mineralized carbon dioxide-containing industrial waste suspension and returning it to the storage tank that provides the feed gas.

[0009] As mentioned above, the loss of carbon dioxide may be zero, at least for a certain period of time during which the method is performed. This is because the amount of carbon dioxide that can be mineralized by the industrial waste suspension is limited, and once this limit is reached, excess gas may be emitted from the industrial waste suspension. Furthermore, the mineralization of carbon dioxide over time is not linear: the mineralization rate (the amount of carbon dioxide mineralized per time step) does not decrease as the amount of carbon dioxide already mineralized increases. The mineralization rate also depends on the specific composition of the industrial waste suspension. Therefore, if the carbon dioxide mineralization rate (at any given time) is exceeded, excess gas may be emitted from the industrial waste suspension. Because the (total) amount of mineralizable carbon dioxide depends on the specific composition of the industrial waste suspension, the exact value of the maximum mineralization rate (at any given time) and the amount of mineralizable carbon dioxide are generally unknown before or during the method.

[0010] To achieve economically efficient processing, the method can be controlled to supply only the amount of carbon dioxide necessary for mineralization to the industrial waste suspension. To prevent excessive supply of the industrial waste suspension, resulting in the supply of carbon dioxide in excess of the amount necessary for mineralization, the method can include a configuration in which a control unit controls the volumetric flow rate of the carbon dioxide-containing gas (volumetric flow rate of the feed gas) and / or the volumetric flow rate of the industrial waste suspension. Preferably, the control unit can actively control each volumetric flow rate in response to the amount of carbon dioxide loss. For example, if a loss of carbon dioxide is detected, the control unit can reduce the volumetric flow rate of the feed gas until only the amount of feed gas necessary for mineralization is supplied to the volumetric flow rate of the industrial waste suspension.

[0011] To quantify the amount of carbon dioxide that has mineralized, the amount of carbon dioxide loss (i.e., the amount of carbon dioxide that has not mineralized) can be subtracted from the amount of carbon dioxide supplied in the (supplied) volumetric flow rate of carbon dioxide-containing gas. To measure the amount of carbon dioxide supplied, the method may include measuring the carbon dioxide concentration of the supplied volumetric flow rate of carbon dioxide-containing gas with a concentration sensor and / or measuring the supplied volumetric flow rate of carbon dioxide-containing gas with a flow meter. If the carbon dioxide concentration in the supply gas is 100%, it is sufficient to measure the volumetric flow rate of the supplied gas to calculate the amount of carbon dioxide supplied.

[0012] However, the volumetric flow rate of the carbon dioxide-containing gas may contain gaseous moisture and / or nitrogen and / or oxygen and / or methane in addition to carbon dioxide. Before being fed to the industrial waste suspension, the feed gas may be stored in a storage tank as a liquid and / or gas. Preferably, the gas is composed of 95% to 100% carbon dioxide. Depending on the application, the gas may also contain renewable carbon dioxide. Renewable carbon dioxide should be understood to mean carbon dioxide of biogenic origin or carbon dioxide extracted from the atmosphere. Biogenic carbon dioxide has the advantage that it is usually obtained in pure form and does not require processing. Biogenic carbon dioxide can be obtained, for example, as a by-product of biomethane production or from the combustion of biomass (biologically derived material containing carbon, hydrogen, and oxygen). Alternatively, the gas may be exhaust gas containing 10 to 25% carbon dioxide. For example, exhaust gas from a cement plant can be used.

[0013] To achieve an easily controllable system, it is advantageous to carry out the mineralization in a (predetermined) volumetric flow rate of the industrial waste suspension outside the collection vessel, rather than in a voluminous collection vessel. Therefore, the volumetric flow rate of the industrial waste suspension can be directed to a bypass (by circulating it from the collection vessel back to the collection vessel). Thus, the method may comprise the following steps: extracting a volumetric flow rate of the industrial waste suspension from the collection vessel; supplying a volumetric flow rate of a carbon dioxide-containing gas to the volumetric flow rate of the industrial waste suspension outside the collection vessel, thereby mineralizing at least a portion of the carbon dioxide in the industrial waste suspension (modified step b); and returning the mineralized carbon dioxide-containing industrial waste suspension to the collection vessel. These steps, in particular together with step c or steps c and d, can be carried out continuously or repeatedly. Once the industrial waste suspension has been fully enriched with carbon dioxide-containing gas, the mineralization can be repeated (for example, until no more calcium ions are eluted or an end criterion is reached).

[0014] Depending on the application, the volumetric flow rate of the industrial waste suspension can be controlled by the control unit, in particular via active control. The control unit can thus be connected to a pump for pumping the industrial waste suspension into the bypass. In this way, to prevent an oversupply of industrial waste suspension and, as a result, an amount of carbon dioxide exceeding the mineralizable amount, the control unit can reduce the volumetric flow rate of the carbon dioxide-containing gas and / or the volumetric flow rate of the industrial waste suspension when a loss of carbon dioxide is detected.

[0015] Depending on the application, the method may include a step of transferring the carbon dioxide enriched industrial waste suspension to an intermediate container, where the discharged excess gas is / can be separated from the mineralized carbon dioxide-containing industrial waste suspension, and the mineralized carbon dioxide-containing industrial waste suspension is returned to the collection container.

[0016] The intermediate vessel offers the advantage of a simple feedback signal for controlling the volumetric flow rate of the carbon dioxide-containing gas and / or the volumetric flow rate of the industrial waste suspension in response to carbon dioxide loss. The liquid level of the industrial waste suspension in the intermediate vessel remains constant as long as excess gas is not released. In this application, "constant" means within a range of ±15 mm. If excess gas is released, i.e., separated from the mineralized carbon dioxide-containing industrial waste suspension, the liquid level of the industrial waste suspension in the intermediate vessel decreases. Therefore, the liquid level of the industrial waste suspension in the intermediate vessel is an indicator of carbon dioxide loss. The same applies to the hydrostatic pressure of the industrial waste suspension in the intermediate vessel. Therefore, the method may include controlling the volumetric flow rate of the carbon dioxide-containing gas so that the liquid level of the (mineralized carbon dioxide-containing) industrial waste suspension in the intermediate vessel remains constant. Thus, the method may include measuring the liquid level of the industrial waste suspension in the intermediate vessel with a level sensor. The level sensor may be, for example, an optical sensor such as a laser or infrared sensor. Alternatively, a pressure sensor positioned at a specific location in the intermediate vessel may be used, in which case the hydrostatic pressure is an indicator of carbon dioxide loss. This allows the control unit to reduce the amount of carbon dioxide-containing supply gas (i.e., the volumetric flow rate of the carbon dioxide-containing gas) and / or reduce the volumetric flow rate of the industrial waste suspension when the liquid level and / or hydrostatic pressure of the (mineralized carbon dioxide-containing) industrial waste suspension drops in the intermediate container.

[0017] Depending on the application, the method may include stirring the carbon dioxide-enriched industrial waste suspension to promote carbon dioxide mineralization. When an intermediate vessel is used, stirring of the carbon dioxide-enriched industrial waste suspension is preferably performed upstream of the intermediate vessel. Stirring can be performed by appropriately shaped / coiled tubing segments (in the bypass) and / or by stirring elements placed in the bypass. Stirring elements placed in the bypass are preferably of the static type (ribs, fins, etc.).

[0018] During the mineralization of carbon dioxide in the industrial waste suspension, the (mineralized carbon dioxide-containing) industrial waste suspension becomes less alkaline, i.e., its pH value decreases. As the mineralization rate decreases over time, it may become economically inefficient to continue the method until all of the feed gas is again discharged as excess gas and further carbon dioxide cannot be mineralized. As the mineralization rate decreases, the pH value also decreases. Therefore, the pH value of the industrial waste suspension is suitable as a simple measurement and detection of the termination criterion. Therefore, the method may include terminating the method when the pH value of the industrial waste suspension reaches a predetermined value. In this case, the predetermined pH value is required to be less than the initial pH value. In some embodiments, the method may terminate when a predetermined pH value between 7 and 10, particularly a predetermined pH value between 8.5 and 9.5, is reached. Depending on the application, the pH value of the industrial waste suspension can also be measured in the collection container. If a bypass is used, the pH value can be measured in the bypass before the carbon dioxide-containing gas is supplied to the industrial waste suspension. Alternatively, or in addition, the method may be terminated when a predetermined amount of mineralized carbon dioxide is reached per unit time or per cubic meter of industrial waste suspension. For example, the method may be terminated when 0.3 to 2 kg of mineralized carbon dioxide per cubic meter is reached. The method may also be terminated when 2000 to 5000 ppm of carbon dioxide is detected in the air above the collection or intermediate container (which corresponds to a carbon dioxide concentration in the air of 0.2 to 0.5%).

[0019] The present invention further relates to a system (also referred to as an installation) for storing carbon dioxide in an industrial waste suspension, preferably capable of carrying out the method for storing carbon dioxide in an industrial waste suspension described above.

[0020] The system comprises a collection container for the industrial waste suspension, having at least one opening for filling and / or extracting the industrial waste suspension, and an inlet valve connected to a storage tank for a carbon dioxide-containing gas. The inlet valve is for supplying a volumetric flow rate of the carbon dioxide-containing gas to the industrial waste suspension. In addition, the system comprises at least one sensor for measuring the amount of carbon dioxide loss, and a control unit connected to the at least one sensor for monitoring the amount of carbon dioxide loss and determining the amount of mineralized carbon dioxide based on the amount of carbon dioxide supplied and the amount of carbon dioxide lost. Preferably, the at least one sensor is a carbon dioxide concentration sensor. Furthermore, at least one sensor may be present and connected to the control unit for monitoring an end criterion.

[0021] Depending on the application, the system may comprise a bypass for supplying a volumetric flow of industrial waste suspension to circulate from the outlet of the collection vessel to the inlet of the collection vessel. Accordingly, the bypass may comprise a pipe. The inlet valve (for carbon dioxide-containing gas) is thereby arranged so that carbon dioxide-containing gas can be supplied (at the supply location) to the volumetric flow of industrial waste suspension between the outlet and inlet of the bypass. Advantageously, the bypass further comprises an intermediate vessel. Preferably, the intermediate vessel is arranged downstream of the inlet valve. The intermediate vessel serves to separate the discharged excess carbon dioxide from the mineralized carbon dioxide-containing industrial waste suspension. Preferably, the intermediate vessel is a riser. From the intermediate vessel, the mineralized carbon dioxide-containing industrial waste suspension is led back into the collection vessel. A feedback pipe may further be arranged between the intermediate vessel and a storage tank for the separated excess carbon dioxide-containing gas. For better mineralization, a stirring element may be arranged between the supply location (where the carbon dioxide-containing gas is supplied to the industrial waste suspension) and the intermediate vessel to stir the carbon dioxide-enriched industrial waste suspension.

[0022] Depending on the application, the system may comprise a concentration sensor for measuring the carbon dioxide concentration of the supplied volumetric flow rate of carbon dioxide-containing gas, and / or a flow meter for measuring the supplied volumetric flow rate of carbon dioxide-containing gas, such that connecting the concentration sensor and / or flow meter to a control unit enables the control unit to determine the amount of carbon dioxide mineralized based on the supplied carbon dioxide and the amount of carbon dioxide lost.

[0023] Depending on the application, at least one sensor for measuring the amount of carbon dioxide loss is disposed in the intermediate vessel and / or the collection vessel. Furthermore, as described above, a liquid level sensor for measuring the liquid level of the industrial waste suspension in the intermediate vessel and / or a pressure sensor for measuring the hydrostatic pressure in the intermediate vessel can be disposed in the intermediate vessel to prevent excessive supply of carbon dioxide to the industrial waste suspension.

[0024] It should be understood that both the general description above and the detailed description of the present embodiments below are intended to provide an overview or framework for understanding the nature and features of the present disclosure. Method embodiments described above also disclose correspondingly designed embodiments of systems for practicing the methods, and vice versa. The accompanying drawings are included to provide a further understanding and are incorporated as part of this specification. The accompanying drawings illustrate various embodiments and, together with the description, explain the principles and operation of the disclosed concepts. [Brief explanation of the drawings]

[0025] The invention described herein can be more fully understood based on the following detailed description and the accompanying drawings, which should not be construed as limiting the invention as set forth in the claims. The drawings are as follows:

[0026] [Figure 1] 1 is a flow chart illustrating a method for storing carbon dioxide in an industrial waste suspension. [Figure 2]2 is a flow chart illustrating the method according to FIG. 1, incorporating further optional steps. [Figure 3] 1 is a schematic diagram illustrating an example of a system for carrying out the method according to the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0027] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The following provides a detailed description of several embodiments. Examples of these embodiments are illustrated in the accompanying drawings, where some, but not all, features are shown. Indeed, the embodiments disclosed herein may be embodied in many different forms and should not be construed as limited to the embodiments disclosed herein. Rather, these embodiments are described so that this disclosure will satisfy applicable legal requirements. Wherever possible, like reference numerals are used to refer to like components or elements.

[0028] FIG. 1 is a flowchart of a method including the following steps: In step (a), a collection container containing an industrial waste suspension is provided; In step (b), a volumetric flow rate of a carbon dioxide-containing gas is supplied to the industrial waste suspension, such that the industrial waste suspension is enriched with carbon dioxide and at least a portion of the carbon dioxide is mineralized in the industrial waste suspension; In step (c), the amount of carbon dioxide lost from the carbon dioxide-enriched industrial waste suspension is measured; and In step (d), the amount of mineralized carbon dioxide is measured based on the amount of carbon dioxide supplied and the amount of carbon dioxide lost. Thus, as indicated by the arrow returning to step (b) on the left side of the flowchart, steps (b) and (c), particularly steps (b) to (d), are carried out continuously or repeatedly.

[0029] Although steps (b) and / or (c) can be carried out within the collection vessel, it is advantageous to carry out these steps outside the collection vessel to achieve more efficient processing. Such a variant of the method of the invention is shown in Figure 2, where a volumetric flow rate of the industrial waste suspension is extracted from the collection vessel before a volumetric flow rate of carbon dioxide-containing gas is supplied to the volumetric flow rate of the industrial waste suspension. After the volumetric flow rate of the carbon dioxide-containing gas is supplied, the industrial waste suspension containing the mineralized carbon dioxide can be returned to the collection vessel.

[0030] FIG. 3 is a schematic diagram of a system / installation for storing carbon dioxide in an industrial waste suspension, particularly for carrying out the method according to the present invention. As shown in the figure, a collection vessel 2 containing an industrial waste suspension 1 is provided. The collection vessel 2 has an opening (inlet) 3 for filling the collection vessel with the industrial waste suspension 1. The opening 3 may be interconnected, for example, with a concrete mixing facility. The collection vessel 2 further has an opening (outlet) 4, which is used to extract the industrial waste suspension 1 from the collection vessel 2, for example, for further processing of the industrial waste suspension 1 after the method is completed or for recycling the industrial waste suspension 1. In the illustrated system, a volume flow of the industrial waste suspension 1 is circulated to a bypass 8. The volume flow of the industrial waste suspension is transported to the bypass 8 by a pump 7. The industrial waste suspension 1 is thereby led from the collection vessel 2 to the bypass 8 via an outlet 6. Downstream of the outlet 6, an inlet valve 22 is arranged, which is connected to a storage tank 15 for a carbon dioxide-containing gas 9. This allows the volumetric flow rate of the carbon dioxide-containing gas 9 to be supplied to the volumetric flow rate of the industrial waste suspension 1, resulting in a carbon dioxide-enriched industrial waste suspension 10. In the bypass 8 downstream of the inlet valve 22, at least a portion of the carbon dioxide in the industrial waste suspension 1 is mineralized. To promote mineralization, a stirring element 11, such as a vortex generator, can be installed in the bypass 8. An intermediate vessel 12 can be provided downstream of the inlet valve 22 (and downstream of the stirring element 11, if installed). In the intermediate vessel 12, excess carbon dioxide-containing gas 14 can be separated from the mineralized carbon dioxide-containing industrial waste suspension 13. From here, the mineralized carbon dioxide-containing industrial waste suspension 13 is returned to the collection vessel 2 via the inlet 5. The excess gas 14 can be sent again to a storage tank 15, which supplies the volumetric flow rate of the carbon dioxide-containing gas 9.

[0031] The excess gas 14 can be monitored to determine the amount of carbon dioxide loss. Therefore, the system may include a concentration sensor 19 for measuring the carbon dioxide concentration in the excess gas 14. Alternatively, or in addition, the system may include a flow meter 18 for measuring the volumetric flow rate of the excess gas 14. Such measurements can be performed between the intermediate vessel 12 and the storage tank 15. Alternatively, these measurements can be performed within the intermediate vessel 12. Based on both measurements, the amount of non-mineralized carbon dioxide, i.e., the amount of carbon dioxide loss, can be determined.

[0032] To measure the amount of mineralized carbon dioxide per time step, the amount of carbon dioxide lost per time step and the amount of carbon dioxide supplied per time step can be measured. Therefore, the system may include an additional concentration sensor for measuring the carbon dioxide concentration in the supplied volumetric flow rate of carbon dioxide-containing gas 9, and / or an additional flow meter 18 for measuring the supplied volumetric flow rate of carbon dioxide-containing gas 9. Such measurements can be performed between storage tank 15 and inlet valve 22. In the illustrated system, supply gas 9 consists of 100% carbon dioxide. Therefore, flow meter 18 is sufficient to measure the amount of carbon dioxide supplied per time step.

[0033] To achieve economically efficient processing, the method can be controlled so that the industrial waste suspension 1 is supplied only in an amount sufficient for mineralization. To prevent excessive supply of the industrial waste suspension 1, resulting in the supply of carbon dioxide in excess of the mineralization amount, the method may include a configuration in which the control unit 16 controls the volumetric flow rate of the supply gas 9 and / or the volumetric flow rate of the industrial waste suspension. The control unit 16 may be configured to actively control each volumetric flow rate in accordance with the amount of carbon dioxide loss calculated from measurements of the industrial waste suspension level in the intermediate vessel 12. Therefore, the method may include a configuration in which the volumetric flow rate of the carbon dioxide-containing gas is controlled so that the level of the carbon dioxide-enriched industrial waste suspension in the intermediate vessel is maintained constant. Therefore, the system may include a level sensor 20 that measures the level of the industrial waste suspension in the intermediate vessel 12. Alternatively, a pressure sensor that measures hydrostatic pressure may be used so that the control unit can actively control the hydrostatic pressure to maintain it constant.

[0034] The treatment can be terminated under several criteria. For example, the method can be terminated when the pH value of the industrial waste suspension in the collection vessel 2 or the bypass 8 reaches a predetermined value. Thus, a pH sensor 17 can be located in the collection vessel 2 or the bypass 8. Additionally or alternatively, the method can include terminating the treatment when the mineralization rate reaches a predetermined value. For monitoring purposes, further sensors (such as a pH sensor or a carbon dioxide concentration sensor) can be provided in the bypass, e.g., downstream of the outlet 6, in the intermediate vessel 12 and / or downstream of the intermediate vessel 12. [Explanation of symbols]

[0035] 1. Industrial waste suspension 2. Collection container 3 entrance 4 exit 5 Inlet 6 Outlet 7. Pump 8. Bypass 9. Gas Supply 10 Carbon dioxide-enriched industrial waste suspension 11 Mixing elements 12 Intermediate container 13 Mineralized carbon dioxide-containing industrial waste suspension 14 Excess gas 15 Storage Tank 16 Control Unit 17 pH sensor 18 Flow meter 19 Concentration sensor 20 Liquid level sensor / pressure sensor 21 additional sensors 22 Inlet valve

Claims

1. A method for storing carbon dioxide in an industrial waste suspension (1), comprising: a. Providing a collection container (2) containing the industrial waste suspension (1); b) supplying a volumetric flow rate of a carbon dioxide-containing gas (9) to the industrial waste suspension (1) so that the industrial waste suspension (1) is enriched with carbon dioxide and at least a portion of the carbon dioxide is mineralized in the industrial waste suspension; c. Measuring the loss of carbon dioxide from the carbon dioxide-enriched industrial waste suspension; and (d) determining the amount of mineralized carbon dioxide based on the amount of carbon dioxide supplied and the amount of carbon dioxide lost.

2. 2. The method according to claim 1, wherein steps b and c, in particular steps b to d, are carried out continuously or repeatedly.

3. 10. A method according to any preceding claim, wherein measuring the amount of carbon dioxide loss comprises monitoring excess gas (14) emitted from the carbon dioxide enriched industrial waste suspension (10).

4. 4. The method of claim 3, wherein monitoring the excess gas (14) comprises measuring the carbon dioxide concentration in the excess gas (14) and / or measuring the volumetric flow rate of the excess gas.

5. 10. The method of any preceding claim, comprising measuring the carbon dioxide concentration of the supplied volumetric flow rate of the carbon dioxide-containing gas using a concentration sensor (19) and / or measuring the supplied volumetric flow rate of the carbon dioxide-containing gas using a flow meter (18) to measure the amount of carbon dioxide supplied.

6. 10. The method according to any preceding claim, characterized in that the method is terminated when the pH value of the industrial waste suspension (1) in the collection vessel (2) reaches a predetermined value and / or when the amount of mineralized carbon dioxide per unit time reaches a predetermined value.

7. The volume flow rate of the carbon dioxide-containing gas (9) supplied to the industrial waste suspension (1) is: extracting a volumetric flow of said industrial waste suspension (1) from said collection vessel (2); supplying a volumetric flow of said carbon dioxide-containing gas (9) to a volumetric flow of said industrial waste suspension (1) outside said collection vessel (2) so that at least a portion of the carbon dioxide is mineralized in said industrial waste suspension; and returning the mineralized carbon dioxide-containing industrial waste suspension (13) to said collection vessel (2).

8. 8. The method according to claim 7, further comprising the step of transferring a volume flow of the industrial waste suspension enriched with carbon dioxide to an intermediate vessel (12), wherein the discharged excess gas can be separated from the mineralized carbon dioxide-containing industrial waste suspension (13), and returning the mineralized carbon dioxide-containing industrial waste suspension (13) to the collection vessel (2).

9. 9. The method according to claim 8, wherein the volumetric flow rate of the carbon dioxide-containing gas (9) is controlled so that the liquid level or hydrostatic pressure of the mineralized carbon dioxide-containing industrial waste suspension (13) in the intermediate vessel is maintained constant.

10. 10. The method according to any one of claims 7 to 9, characterized in that the volumetric flow rate of the carbon dioxide-containing gas and / or the volumetric flow rate of the industrial waste suspension are controlled by a control unit (16), in particular by active control depending on the amount of carbon dioxide loss.

11. 10. The method according to claim 9, wherein the liquid level of the industrial waste suspension in the intermediate container (12) is measured by a liquid level sensor (20) and / or the hydrostatic pressure in the intermediate container (12) is measured by a pressure sensor.

12. 10. A method according to any preceding claim, characterized in that the carbon dioxide enriched industrial waste suspension (10) is agitated to promote carbon dioxide mineralization.

13. 13. The method according to claims 8 and 12, characterized in that the carbon dioxide-enriched industrial waste suspension (10) is agitated upstream of the intermediate vessel (12).

14. 9. A method according to claim 8, characterized in that the separated excess gas (14) is returned to a storage tank (15) which supplies the volume flow of the carbon dioxide-containing gas (9).

15. A system for storing carbon dioxide in an industrial waste suspension (1), comprising: a collection container (2) for the industrial waste suspension, having at least one opening (3, 4) for filling and / or extracting the industrial waste suspension; b. an inlet valve (22) connected to a storage tank (15) for a carbon dioxide-containing gas (9) for supplying a volumetric flow rate of the carbon dioxide-containing gas (9) to the industrial waste suspension (1); c. at least one sensor (17, 19, 20, 21) for measuring the loss of carbon dioxide; and d) a control unit (16) connected to said at least one sensor (17, 19, 20, 21) for monitoring the amount of carbon dioxide loss and determining the amount of carbon dioxide mineralized based on the amount of carbon dioxide supplied and the amount of carbon dioxide lost.

16. 16. The system according to claim 15, further comprising a bypass (8) for supplying a volumetric flow of the industrial waste suspension (1) to circulate from the outlet (6) of the collection vessel (2) to the inlet (5) of the collection vessel (2), the inlet valve (22) being arranged so that the carbon dioxide-containing gas (9) can be supplied to the volumetric flow of the industrial waste suspension (1) in the bypass (8).

17. 17. The system according to claim 16, wherein the bypass (8) comprises an intermediate vessel (12) downstream of the inlet valve (22).

18. 18. The system according to claim 17, characterized in that a stirring element (11) is arranged between the intermediate vessel (12) and the inlet valve (22) for mixing the carbon dioxide-containing gas with a volumetric flow rate of carbon dioxide.

19. 19. The system according to any one of claims 15 to 18, characterized in that at least one sensor for measuring the loss of carbon dioxide is arranged in the intermediate container (12) and / or in the collection container (2).

20. 20. The system according to any one of claims 15 to 19, characterized in that a liquid level sensor (20) for measuring the liquid level of the industrial waste suspension in the intermediate container (12) and / or a pressure sensor (20) for measuring the hydrostatic pressure in the intermediate container (12) are arranged in the intermediate container (12).

21. 21. The system according to any one of claims 15 to 20, characterized in that it comprises a concentration sensor (19) for measuring the carbon dioxide concentration of the supplied volumetric flow rate of the carbon dioxide-containing gas (9), and / or a flow meter (18) for measuring the supplied volumetric flow rate of the carbon dioxide-containing gas (9).

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