Valve assembly and method for operating a valve assembly

Abstract

The present invention relates to a vertical valve arrangement for channelling a predetermined target quantity of a granular material by means of gravity into a region located below the valve arrangement, comprising a first shut-off element, a second shut-off element, a third shut-off element and a fourth shut-off element, which are arranged in series, wherein the first shut-off element is arranged above the second shut-off element, the second shut-off element is arranged above the third shut-off element, and the third shut-off element is arranged above the fourth shut-off element, an antechamber, which is located between the first shut-off element and the second shut-off element, a lock chamber, which is located between the second shut-off element and the third shut-off element, and an emptying chamber, which is located between the third shut-off element and the fourth shut-off element.

Description

[0001] R.415521

[0002] - 1 -

[0003] Description

[0004] title

[0005] Valve arrangement and method for operating a valve arrangement

[0006] State of the art

[0007] The present invention relates to a vertical valve arrangement for introducing a predetermined target quantity of a granular material by means of gravity, as well as a method for operating such a vertical valve arrangement and a desorption plant.

[0008] In many process plants, a granular material is conveyed. This material often needs to be fed into and removed from various process steps in predetermined quantities using valve technology. Frequently, different absolute pressures and gas compositions are required for the various process steps, meaning the valve technology must meet stringent leak tightness requirements. In particular, it must be ensured that no or only minimal gas exchange can occur between different process chambers to avoid negatively impacting the processes. One example of a process plant is a desorption unit for the recovery of carbon dioxide, which must be separated from a granular material in a desorption process. In such a desorption process, for example, no atmospheric oxygen may enter the process chamber.However, due to the granular material, granular material or its abrasion particles can become trapped and / or adhere to the seat and / or guide area of ​​the inlet and outlet valves. This poses a risk of insufficient valve sealing when closed, which in extreme cases can lead to gas exchange through the valves. R.415521.

[0009] -2 -

[0010] Disclosure of the invention

[0011] In contrast, the inclined, in particular vertical, valve arrangement according to the invention for introducing a predetermined target quantity of a granular material by means of gravity with the features of claim 1 has the advantage that a reliable gas-tight separation is possible between an area located upstream of the valve arrangement and an area located downstream of the valve arrangement, into which the target quantity is to be introduced. In particular, it can be prevented that granular material and / or abrasion of this material or the like accumulates and / or is deposited on sealing surfaces of the valve arrangements and thus can lead to leaks in the valve arrangement.

[0012] According to the invention, this is achieved by the inclined, vertical valve arrangement comprising a first, a second, a third, and a fourth shut-off element. The four shut-off elements are arranged in series, with the first shut-off element positioned above the second, the second above the third, and the third above the fourth. Furthermore, the inclined, particularly vertical, valve arrangement includes a pre-chamber located between the first and second shut-off elements, a lock chamber located between the second and third shut-off elements, and a discharge chamber located between the third and fourth shut-off elements. Thus, the four shut-off elements and the three chambers are arranged in series, particularly vertically one above the other. The pre-chamber is located above the lock chamber, and the lock chamber is located above the discharge chamber.Shut-off elements are provided between each chamber. Two shut-off elements are arranged upstream of the lock chamber in the direction of flow, and two further shut-off elements are arranged downstream of the lock chamber in the direction of flow. This allows one of the shut-off elements to be configured as a metering valve and one as a gas-tight valve. Specifically, the second and fourth shut-off elements downstream in the direction of flow are configured as gas-tight valves, while the first and third shut-off elements are configured as metering valves. R.415521.

[0013] - 3 -

[0014] Consequently, the valve arrangement is inclined relative to the horizontal, in particular vertically oriented.

[0015] The granular material is particularly free-flowing or pourable. The granular material is preferably a sorption or adsorption material for gas separation, especially CO2 separation.

[0016] The area located below the valve arrangement can in particular be a desorption chamber or an area located downstream of a desorption chamber of a gas separation system.

[0017] The dependent claims describe preferred embodiments of the invention.

[0018] Preferably, the second and fourth shut-off elements are designed as gas-tight valves, which in particular have an elastomer sealing element for reliable sealing.

[0019] Preferably, the first, second, third and fourth shut-off elements are designed as a gate valve, seat valve, ball valve, rotary flap valve or pinch valve.

[0020] Preferably, all four shut-off elements are technically identical valves, in particular gate valves or poppet valves. Alternatively, preferably, the first and third shut-off elements are technically identical, and the second and fourth shut-off valves are technically identical, with the second and fourth shut-off valves then being technically different from the first and third shut-off valves. In particular, since the first and third shut-off elements only have a metering function, they can be designed as cost-effective shut-off elements.

[0021] Preferably, the lock chamber has a larger volume than the pre-chamber and also a larger volume than the discharge chamber.

[0022] Preferably, the volume of the pre-chamber is equal to the volume of the discharge chamber. This allows, in particular, a vertically compact valve arrangement. R.415521

[0023] -4 -

[0024] Preferably, the valve arrangement comprises a control device configured to actuate the first, second, third, and fourth shut-off elements such that the second shut-off element is fully open before the first shut-off element is opened, and the fourth shut-off element is fully open before the third shut-off element is opened. This prevents the second and fourth shut-off elements from adhering to granular material or other solids, ensuring a gas-tight seal at all times.

[0025] Furthermore, the present invention comprises a method for operating a vertical valve arrangement according to the invention. The method includes the following steps, in particular starting from a state of the valve arrangement in which all four shut-off elements are closed. In a first step, the third shut-off element is opened, while the first, second, and fourth shut-off elements are closed. This connects the lock chamber and the discharge chamber. In a second step, the lock chamber and the discharge chamber connected to it are inerted or evacuated. This can, for example, create a vacuum in the lock chamber and the discharge chamber. In a third step, the third shut-off element is closed and the second shut-off element is opened, so that the pre-chamber and the lock chamber are connected.The lock chamber and the discharge chamber are separate. In a fourth step, the first shut-off element is opened, allowing granular material from a first reservoir to fall directly into the lock chamber through the pre-chamber due to gravity. Because the second shut-off element is open, there is no risk of granular material accumulating or adhering to the sealing surfaces of the second shut-off element.

[0026] In a fifth step, the second shut-off element is closed, which, since there are no impairments caused by granular material or other solids, enables a gas-tight seal between the lock chamber and the pre-chamber.

[0027] In a sixth step, pressure equalization takes place between the lock chamber and the discharge chamber. Preferably, the R.415521

[0028] -5 -

[0029] The lock chamber is evacuated again if, in the second step, the lock chamber and the emptying chamber have been evacuated, since a corresponding vacuum is present in the emptying chamber.

[0030] In a seventh step, the fourth shut-off element is opened, while the third shut-off element is still closed.

[0031] In an eighth step, the third shut-off element is opened, allowing the granular material to be discharged by gravity from the lock chamber through the emptying chamber to the downstream area, such as a desorption unit of the valve assembly. Thus, as with the second shut-off element, this prevents granular material from settling or adhering to the sealing surfaces of the fourth shut-off element, which could lead to leakage problems.

[0032] Preferably, the method according to the invention is carried out such that the second and fourth shut-off elements are fully opened before the first and third shut-off elements are opened. This allows for particularly good protection of the sealing surfaces of the second and fourth shut-off elements.

[0033] In the sixth step of pressure equalization between the lock chamber and the discharge chamber, the pressure equalization can preferably be achieved to ambient pressure. Alternatively, pressure equalization can also be achieved by creating a vacuum.

[0034] The invention further relates to a desorption system for a gas separation system with a desorption chamber and at least one valve arrangement according to one of the preceding claims for introducing a predetermined target quantity of a granular sorption material by means of gravity into the desorption chamber arranged below the valve arrangement or for removing a predetermined target quantity of a granular sorption material by means of gravity from the desorption chamber arranged above the valve arrangement.

[0035] Preferably, the desorption system comprises a first valve arrangement according to the invention as described above on an R.415521

[0036] - 6 -

[0037] The inlet valve of the desorption system and a second valve arrangement according to the invention, as described above, are located at an outlet valve of the desorption system. The first valve arrangement is configured to introduce the granular material into the desorption system, and the second valve arrangement is configured to remove the granular material from which carbon dioxide has been extracted in the desorption system. Preferably, before the target quantity of the granular material is fed from the first valve arrangement, which is designed for introduction, into the desorption system, the target quantity is introduced under a vacuum. This allows desorption to be carried out more quickly in the desorption system.

[0038] The invention further relates to a gas separation system, in particular a direct air capture (DAC) system for separating a gas, especially carbon dioxide, from air, particularly ambient air, with a desorption system according to the type described above. The gas separation system preferably includes an adsorption system which is fluidically connected to the desorption system for the circulation of the granular material or sorption material.

[0039] drawing

[0040] A preferred embodiment of the invention is described in detail below with reference to the accompanying drawing. The drawing shows:

[0041] Figures 1 to 8 are schematic representations of a valve arrangement and a method for operating the valve arrangement according to a preferred embodiment of the invention and

[0042] Figure 9 shows a schematic representation of a desorption plant with a valve arrangement according to the invention.

[0043] Preferred embodiments of the invention

[0044] Below, with reference to Figures 1 to 9, a vertical valve arrangement 1, a method for operating the valve arrangement and an R.415521 are described.

[0045] - 7 -

[0046] A desorption plant according to a preferred embodiment of the invention is described in detail.

[0047] As can be seen from Figure 1, the vertical valve arrangement 1 comprises a first port 30, to which an upper reservoir 3 is arranged. Furthermore, the valve arrangement 1 comprises a second port 40, which defines an outlet of the valve arrangement. A lower reservoir for the granular material 2 is provided at the second port 40, for example.

[0048] The vertical valve arrangement 1 is designed to introduce and discharge a predetermined target quantity M of a granular material 2.

[0049] The vertical valve arrangement 1 further comprises a first shut-off element 11, a second shut-off element 12, a third shut-off element 3 and a fourth shut-off element 14. As shown in Figure 1, the four shut-off elements 11, 12, 13, 14 are arranged in a row one above the other.

[0050] Furthermore, the vertical valve arrangement 1 includes a pre-chamber 5, which is arranged between the first and second shut-off elements 11, 12.

[0051] Furthermore, a lock chamber 6 is arranged below the pre-chamber 5, which lies between the second and third shut-off elements 12, 13. The valve arrangement also includes a drain chamber 7, which is arranged between the third and fourth shut-off elements 13, 14.

[0052] As can be seen in Figure 1, the four shut-off elements and the three chambers are arranged in a row, one above the other. Preferably, the chambers are cylindrical.

[0053] The four shut-off elements 11, 12, 13, 14 are all technically identical and, in this embodiment, are gate valves. It should be noted that alternative shut-off elements, such as poppet valves or flaps that pivot about an axis, could also be provided.

[0054] As can be seen further in Figure 1, the lock chamber 6 has a larger volume than the volumes of the pre-chamber 5 and the discharge chamber 7. R.415521

[0055] - 8 -

[0056] Preferably, the volumes of the pre-chamber 5 and the emptying chamber 7 are the same size.

[0057] The four shut-off elements 11, 12, 13, 14 must now fulfill two main criteria during a lock operation: firstly, the metering of the granular material 2, and secondly, the gas-tight, reliable sealing of the chambers. The first and third shut-off elements 11, 13 are designed as metering valves, and the second and fourth shut-off elements 12, 14 are designed as sealing valves. Thus, according to the invention, the functions of metering and sealing can be divided by two shut-off elements connected in series, arranged in pairs before and after the lock chamber.

[0058] The first and third shut-off elements, which are designed as metering valves, interrupt the flow of the granular material 2. The granular material 2 can rest on the metering valves, i.e., the first and third shut-off elements 11, 13, in the form of a column of material. No column of material rests on the second and fourth shut-off elements 12, 14 during the transfer operation, thus preventing the risk of contamination of the sealing surfaces of the second and fourth shut-off elements 12, 14.

[0059] Furthermore, the valve arrangement 1 includes a control unit 10. The control unit 10 is configured to actuate the four shut-off elements 11, 12, 13, 14 in order to open and close them. The control unit 10 is configured such that the second shut-off element 12 is fully open before the first shut-off element 11 is opened, and the fourth shut-off element 14 is fully open before the third shut-off element 13 is opened.

[0060] The procedure for operating the vertical valve arrangement 1 is described in detail below with reference to Figures 1 to 8. In a starting position, all four shut-off elements 11, 12, 13, 14 are in the closed state.

[0061] In a first step S1 (see Figure 1), the third shut-off element 13 is opened (arrow A). The first, second, and fourth shut-off elements 11, 12, 14 remain in the closed position. Thus, the lock chamber 6 and the discharge chamber 7 are connected. R.415521

[0062] - 9 -

[0063] In a second step S2, the lock chamber 6 and the emptying chamber 7 are inerted or evacuated. This is indicated by arrows B in Figure 1. For this purpose, a compressor 15 or the like is arranged on the lock chamber 6, which extracts gas from the lock chamber 6 and the emptying chamber 7 connected to the lock chamber 6 (due to the open third shut-off element 13).

[0064] In a third step S3, the third shut-off element 13 is closed (arrow C in Figure 2) and the second shut-off element 12 is opened (arrow D in Figure 2). Thus, the pre-chamber 5 and the lock chamber 6 are connected. If necessary, the lock chamber 6 can preferably be inerted or evacuated again, since gas may have re-entered the lock chamber 6 when the pre-chamber 5 was opened.

[0065] In a fourth step S4, the first shut-off element 11 is opened (arrow E in Figure 3). This allows granular material 2, as indicated by arrow F, to fall through the open first shut-off element 11 and the open second shut-off element 12 through the pre-chamber 5 into the lock chamber 6 due to gravity.

[0066] Once a predetermined target quantity M has passed the first shut-off element 11, the first shut-off element 11 is closed again, as shown by arrow G in Figure 4. The second shut-off element 12 remains open. As can be further seen in Figure 4, due to gravity, the target quantity M of the granular material 2 has meanwhile completely fallen into the lock chamber 6 (arrow F in Figure 4).

[0067] In a fifth step S5, the second shut-off element 12 is closed (see arrow H in Figure 5). This separates the pre-chamber 5 and the lock chamber 6. The target quantity M rests on the third shut-off element 13 (see Figure 5). Thus, a predetermined target quantity M has been introduced into the lock chamber 6.

[0068] In a sixth step S6, pressure equalization takes place between the lock chamber 6 and the discharge chamber 7. As indicated in Figure 6, gas can, for example, be introduced into the lock chamber 6 and / or the R.415521.

[0069] - 10 -

[0070] Emptying chamber 7 is introduced until the same pressure prevails in lock chamber 6 and emptying chamber 7. Alternatively, lock chamber 6 and emptying chamber 7 can be evacuated again to the same negative pressure level.

[0071] In a seventh step S7, the fourth shut-off element 14 is opened, while the third shut-off element 13 remains closed. This is indicated by the arrow K in Figure 7. The target quantity M is still present on the closed third shut-off element 13.

[0072] In an eighth step S8, shown in Figure 8, the third shut-off element 13 is opened, as indicated by the arrow L in Figure 8. The target quantity M can then be conveyed by gravity through the opened third shut-off element 13 and the opened fourth shut-off element 14 via a second outlet 40 on the fourth shut-off element 14 into a further area 4 downstream of the valve arrangement 1.

[0073] Figure 9 shows an example of a desorption plant 9 in which carbon dioxide (CO2), which has been adsorbed on the granular material 2, is removed. A first valve arrangement 1 according to the invention is connected upstream of the desorption plant 9, and an identically constructed second valve arrangement 1 according to the invention is connected downstream of the desorption plant 9 in the flow direction. This allows for the introduction and removal of granular material 2, whereby during removal, the granular material 2 is discharged as material 2' without the carbon dioxide desorbed in the desorption plant 9.

[0074] As described above, the design of the valve assembly 1 at the shut-off elements 11, 12, 13, 14 allows for a separation of the dosing and sealing functions. The shut-off elements 12 and 14, which are designed for sealing, can always remain open during the flow of the granular material 2, thus minimizing the risk of material or other solids adhering to or depositing on the sealing surfaces of the second and fourth shut-off elements 12, 14. Therefore, the second and fourth sealing elements 12, 14 exhibit the highest sealing performance and ensure gas tightness of the valve assembly. With the first and third shut-off elements 11, 13, it is possible for granules to adhere to the sealing surfaces of the R.415521

[0075] - 11 -

[0076] Shut-off elements 11 and 13 are used because, for example, the first shut-off element 11, when closing to interrupt the material flow from reservoir 3, can come into contact with the granular material 2. Material may then adhere to the sealing surfaces of the first shut-off element 11, potentially leading to leaks. This risk also exists with the third shut-off element 13, as the target quantity m of material 2 rests on the third shut-off element 13 as a column of material, creating a risk of material adhering to areas of the third shut-off element 13. However, the first and third shut-off elements 11 and 13 are only used for metering, so any material adhering to them is harmless.

[0077] Thus, according to the present invention, each of the shut-off elements 11, 12, 13, 14 can be optimally designed according to its function. With the method according to the invention, no material is in contact with the second and fourth shut-off elements 12, 14 during the sluice operation, so that the risk of material adhering to the sealing surfaces of the second and fourth shut-off elements 12, 14 is low.

[0078] It should be noted that the invention can be used not only in desorption plants, but also in other plants where transfer processes have to be carried out, which are in particular accompanied by inerting and / or vacuuming.

Claims

R.415521 - 12 - Claims 1. Inclined, in particular vertical, valve arrangement (1) for introducing a predetermined target quantity (M) of a granular material (2), in particular sorption material, by means of gravity into a region (5, 6, 7) arranged below the valve arrangement (1), in particular into a desorption chamber or from a desorption chamber of a gas separation plant, comprising: - a first shut-off element (11), a second shut-off element (12), a third shut-off element (13) and a fourth shut-off element (14) arranged in series, wherein the first shut-off element (11) is arranged above the second shut-off element (12), the second shut-off element (12) is arranged above the third shut-off element (13) and the third shut-off element (13) is arranged above the fourth shut-off element (14), - a pre-chamber (5) which is arranged between the first shut-off element (11) and the second shut-off element (12), - a lock chamber (6) which is arranged between the second shut-off element (12) and the third shut-off element (13), and - a drain chamber (7) which is arranged between the third shut-off element (13) and the fourth shut-off element (14) 2. Valve arrangement (1) according to claim 1, wherein the second shut-off element (12) and the fourth shut-off element (14) are designed as gas-tight valves and in particular have elastomer sealing elements for sealing.

3. Valve arrangement (1) according to one of the preceding claims, wherein the shut-off elements (11, 12, 13, 14) are designed as a gate valve or poppet valve or ball valve or rotary flap valve or pinch valve.

4. Valve arrangement (1) according to one of the preceding claims, wherein all shut-off elements (11, 12, 13, 14) are identical, or R.415521 - 13 - wherein the first and third shut-off elements (11, 13) are identical and the second and fourth shut-off valves (12, 14) are identical but different from the first and third shut-off elements (11, 13).

5. Valve arrangement (1) according to one of the preceding claims, wherein the lock chamber (6) has a larger volume than the pre-chamber (5) and / or wherein the lock chamber (6) has a larger volume than the discharge chamber (7).

6. Valve arrangement (1) according to one of the preceding claims, wherein a volume of the pre-chamber (5) is equal to a volume of the discharge chamber (7).

7. Valve arrangement (1) according to one of the preceding claims, further comprising a control device (10) which is configured to control the shut-off elements (11, 12, 13, 14) such that the second shut-off element (12) is always fully open before the first shut-off element (11) is opened and the fourth shut-off element (14) is always fully open before the third shut-off element (13) is opened.

8. Desorption system for a gas separation system with a desorption chamber and at least one valve arrangement (1) according to one of the preceding claims for introducing a predetermined target quantity (M) of a granular sorption material by means of gravity into the desorption chamber arranged below the valve arrangement (1) or for removing a predetermined target quantity (M) of a granular sorption material by means of gravity from the desorption chamber arranged above the valve arrangement (1).

9. Desorption system according to claim 8, comprising a first valve arrangement (1) according to one of claims 1 to 7 at an inlet lock of the desorption system and a second valve arrangement (1) according to one of claims 1 to 7 at an outlet lock of the desorption system. R.415521 - 14 - 10. Gas separation system for separating a gas, in particular carbon dioxide, from air, in particular ambient air, with a desorption system according to claim 8 or 9.

11. Gas separation system according to claim 8 or 9 with an adsorption system which is fluidically connected to the desorption system for the circulation of the granular material (2).

12. Method for operating an inclined, in particular vertical, valve arrangement (1) according to one of the preceding claims, comprising the steps: - Opening (S1) of the third shut-off element (13), with the first shut-off element (11), the second shut-off element (12) and the fourth shut-off element (14) closed, so that the lock chamber (6) and the emptying chamber (7) are connected to each other, - Intercepting or evacuating (S2) the lock chamber (6) and the emptying chamber (7), - Closing (S3) of the third shut-off element (13) and opening of the second shut-off element (12), so that the pre-chamber (5) and the lock chamber (6) are connected to each other, - Opening (S4) of the first shut-off element (11), so that the granular material (2) falls through the pre-chamber (5) directly into the lock chamber (6) due to gravity, - Closing (S5) of the second shut-off element (12), - Pressure equalization (S6) of the pressures in the lock chamber (6) and the emptying chamber (7), - Opening (S7) of the fourth shut-off element (14) and then - Opening (S8) of the third shut-off element (13) so that the granular material (2) is discharged from the lock chamber (6) through the emptying chamber (7) by means of gravity.

13. Method according to claim 12, wherein the second shut-off element (12) is fully opened before the first shut-off element (11) is opened and wherein the fourth shut-off element (14) is fully opened before the third shut-off element (13) is opened. R.415521 - 15 - 14. Method according to claim 12 or 13, wherein in the step of pressure equalization in the lock chamber (6) and the emptying chamber (7) the pressure is equalized to ambient pressure or to a pressure below ambient pressure.

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