Ejector nozzle and use of the ejector nozzle

Abstract

The invention relates to an ejector nozzle having a liquid-carrying duct and a gas-carrying duct. The gas-carrying duct opens into the liquid-carrying duct upstream of an outlet opening. The insert acting as a flame arrester is positioned in the gas-carrying duct. The insert is configured in such a way that no gas can flow around the insert. The invention furthermore relates to use of the ejector nozzle in a jet loop reactor.

Claims

1. An ejector nozzle, comprising: a liquid-carrying duct and a gas-carrying duct, wherein the gas-carrying duct opens into the liquid-carrying duct upstream of an outlet opening, such that a high-speed liquid flow is generated in the liquid-carrying duct and a vacuum forms at an opening of the gas-carrying duct into the liquid-carrying duct, by which gas is sucked into the liquid-carrying duct, wherein the liquid-carrying duct comprises a diameter constriction upstream of the opening of the gas-carrying duct into the liquid-carrying duct, wherein the outlet opening has a cross-sectional area smaller than a cross-sectional area of the liquid-carrying duct upstream of the diameter constriction, wherein an insert acting as a flame arrester is positioned in the gas-carrying duct upstream of where the gas-carrying duct opens into the liquid-carrying duct, wherein the insert is configured in such a way that a whole gas stream passes through the flame arrester and no gas flows around the insert, and wherein said gas-carrying duct comprises at least one gas selected from the group consisting of acetylene, ethylene oxide and ethene.

2. The ejector nozzle of claim 1, wherein the insert acting as a flame arrester comprises at least one layer.

3. The ejector nozzle of claim 2, wherein the insert acting as a flame arrester additionally comprises a supporting layer.

4. The ejector nozzle of claim 1, wherein the insert acting as a flame arrester comprises a first sintered layer, a supporting layer and a second sintered layer in a flow direction of gas through the insert acting as a flame arrester.

5. The ejector nozzle of claim 1, wherein the liquid-carrying duct is a central duct and the gas-carrying duct surrounds the liquid-carrying duct.

6. The ejector nozzle of claim 5, wherein the insert acting as a flame arrester is of cylindrical configuration and is arranged parallel to a flow direction of gas in the gas-carrying duct so that the gas changes direction of flow to flow through the insert acting as a flame arrester.

7. The ejector nozzle of claim 5, wherein the insert acting as a flame arrester is in a form of a disk and is arranged perpendicularly to a flow direction of gas in the gas-carrying duct.

8. The ejector nozzle of claim 1, wherein a temperature sensor is arranged in a region of the insert acting as a flame arrester.

9. The ejector nozzle of claim 1, wherein an additive injection is provided in a region of the insert acting as a flame arrester.

10. The ejector nozzle of claim 9, wherein the additive injection is an injection of white oil.

11. The ejector nozzle of claim 1, wherein the gas-carrying duct upstream of the insert acting as a flame arrester contains packing elements.

12. A method for contacting a gas phase with a liquid phase, the method comprising: bringing the gas phase and the liquid phase into contact in an apparatus comprising the ejector nozzle of claim 1, wherein the gas phase is explosive.

13. The method of claim 12, wherein the apparatus is a jet loop reactor, an absorber, a circulating gas reactor, a bubble column, or a trickle bed in a stirred tank.

14. The method of claim 12, wherein the apparatus is a jet loop reactor or a circulating gas reactor, and acetylene, ethene, or ethylene oxide reacts in the apparatus as a gaseous reagent.

15. The ejector nozzle of claim 1, wherein the insert acting as a flame arrester is positioned such that a first annular gap is formed between an outer wall of the gas-carrying duct and the insert acting as a flame arrester and a second annular gap is formed between an inner wall of the gas-carrying duct and the insert acting as a flame arrester.

16. The ejector nozzle of claim 4, wherein said first sintered layer and/or said second sintered layer is a sintered material selected from a sintered glass, a ceramic or a sintered metal.

Description

(1) In the drawings:

(2) FIG. 1 shows an ejector nozzle having a cylindrical insert, which is arranged parallel to the direction of flow of the gas and acts as a flame arrester,

(3) FIG. 2 shows an ejector nozzle having an insert acting as a flame arrester in the form of a disk, and

(4) FIG. 3 shows a detail of an ejector nozzle with additive injection and a temperature sensor.

(5) FIG. 1 shows an ejector nozzle having a cylindrical insert, which is arranged parallel to the direction of flow of the gas and acts as a flame arrester.

(6) An ejector nozzle 1 comprises a liquid-carrying duct 3 and a gas-carrying duct 5. In the embodiment shown here, the liquid-carrying duct 3 extends centrally in the ejector nozzle 1, and the gas-carrying duct 5 surrounds the liquid-carrying duct 3. As an alternative, however, any other desired arrangement of the liquid-carrying duct 3 and the gas-carrying duct 5 is also possible. For example, the central duct can also be a gas-carrying duct, and the duct surrounding the central duct can also be a liquid-carrying duct. Moreover, provision can also possible be made, instead of having one surrounding duct, for the central duct to be surrounded by a plurality of ducts extending annularly around the central duct. However, the embodiment shown here is preferred.

(7) The gas-carrying duct 5 opens into the liquid-carrying duct 3 upstream of an outlet opening 7, wherein the liquid-carrying duct has a diameter constriction 11 upstream of the opening 9 of the gas-carrying duct. Owing to the diameter constriction, the speed of the liquid is increased before it emerges from the ejector nozzle 1 through the outlet opening 7. During this process, a vacuum is formed in the region of the opening 9 of the gas-carrying duct, and the gas is sucked in by the liquid. At the same time, the speed is such that good mixing of gas and liquid is achieved. To improve mixing, it is possible to attach a momentum exchange tube (not shown here) to the opening 9. The momentum exchange tube preferably has openings through which liquid surrounding the momentum exchange tube is sucked in. This liquid is mixed with the mixture of gas and liquid emerging from the opening 9. The momentum exchange tube is then generally adjoined by a diffuser, in which the speed is reduced and pressure is built up.

(8) In order to avoid propagation of a flame front into the gas-carrying duct 5 when using explosive gases or to prevent the flame front entering the reactor in the case of ignition of the gas in the region of the gas-carrying duct 5, an insert 13 acting as a flame arrester is provided in the region of the gas-carrying duct 5. In the embodiment shown in FIG. 1, the insert 13 acting as a flame arrester is of cylindrical configuration and is arranged parallel to the main direction of flow of the gas in the gas-carrying duct 5. In this case, the insert 13 acting as a flame arrester is positioned in such a way that a first annular gap 15 is formed between the outer wall 17 of the gas-carrying duct 5 and the insert 13 acting as a flame arrester and a second annular gap 19 is formed between the inner wall 21 of the gas-carrying duct 5 and the insert 13 acting as a flame arrester.

(9) To ensure that all the gas must flow through the insert 13 acting as a flame arrester and that no gas can flow past said insert, the second annular gap 19 is closed with respect to the gas-carrying duct 5 on the side facing away from the outlet opening 7. For this purpose, it is possible, for example, to insert a disk 23, which rests by means of one side on the inner wall 21 of the gas-carrying duct 5 and by means of the other side on the insert 13 acting as a flame arrester.

(10) In operation, the gas flows through the gas-carrying duct into the first annular gap 15, from the first annular gap, through the insert 13 acting as a flame arrester, into the second annular gap 19 and, from there, onward to the opening 9 of the gas-carrying duct 5 into the liquid-carrying duct 3.

(11) In the embodiment shown here, the insert 13 acting as a flame arrester comprises a supporting layer 25, a first sintered layer 27 and a second sintered layer 29, wherein the construction of the insert 13 acting as a flame arrester is configured in such a way that the gas first of all flows through the first sintered layer 27, then through the supporting layer 25 and, after this, through the second sintered layer 29. In this arrangement, the sintered layers 27, 29 each rest on the supporting layer 29. Finally, the gas carrying duct 5 comprises packing elements 30 upstream of the insert 13.

(12) An ejector nozzle having an insert acting as a flame arrester in the form of a disk is shown in FIG. 2.

(13) In contrast to the embodiment shown in FIG. 1, the insert 13 acting as a flame arrester in the embodiment shown in FIG. 2 is not of cylindrical design and accommodated in the gas-carrying duct parallel to the main direction of flow of the gas but is in the form of a disk. Here, the insert 13 acting as a flame arrester rests in each case on the inner wall 21 and the outer wall 17 of the gas-carrying duct. In this case, the first sintered layer 27 is situated on the incident flow side and is aligned perpendicularly to the main direction of flow of the gas. In corresponding fashion, the supporting layer 25 and the second sintered layer 29 are aligned perpendicularly to the main direction of flow of the gas in the gas-carrying duct 5. By virtue of the fact that the insert 13, which is configured as a disk and acts as a flame arrester, rests both on the inner wall 21 and on the outer wall 17 of the gas-carrying duct 5, no gas can flow around the insert 13 acting as a flame arrester. All the gas must flow through the insert 13 acting as a flame arrester.

(14) FIG. 3 shows a detail of an ejector nozzle having additive injection and a temperature sensor.

(15) In the detail shown here, the insert 13 acting as a flame arrester is of cylindrical configuration and positioned parallel to the flow of gas in the gas-carrying duct 5, as in FIG. 1.

(16) To enable the gas to flow through the insert 13 acting as a flame arrester and to obtain sufficient stability in the insert 13 acting as a flame arrester, the supporting layer 25 is configured in the form of a ring having bores 35. Owing to the bores 35 the pressure loss in the supporting layer 25 is very much lower than the pressure loss in the sintered layers 27, 29, in which the gas must flow through the pores contained therein. In order to keep the total pressure loss as small as possible, it is therefore advantageous to make the sintered layers 27, 29 as thin as possible. In order nevertheless to obtain a stable insert 13 acting as a flame arrester, the supporting layer is necessary. Since sintered layers are generally brittle, there is the risk that a sintered layer will break without an additional supporting layer, owing to the pressure differences and mechanical stresses in the gas-carrying duct 5, especially if a flame front forms or especially if the gas detonates, and therefore that the effect as a flame arrester will no longer be present.

(17) For temperature measurement in the region of the insert 13 acting as a flame arrester in order, for example, to detect the formation of a flame front which may impair the operation of the insert 13, it is possible, as shown here, to insert a temperature sensor 31. For this purpose, as shown here, it is possible, for example, to make a groove 33 in the inner wall 21 delimiting the gas-carrying duct 5, for example, in which groove the temperature sensor 31 is accommodated. The temperature sensor 31 can be fixed in the groove by bonding it in with adhesive that is stable relative to the conditions prevailing in the gas-carrying duct 5 or by soldering, for example. To mount the temperature sensor, it is also possible to insert a supporting tube into the groove 33 and to guide the temperature sensor in the supporting tube. Care should be taken here to ensure that the lead-through is sealed off relative to the gas-carrying duct 5 to ensure that no gas can flow into the supporting tube. Sealing is also necessary if the temperature sensor 31 is inserted directly into the groove 33 to ensure that no gas can flow out via the guide for the temperature sensor 31.

(18) In order to detect flame formation in time, it is preferred here if the temperature sensor projects into the second annular space 19, as shown here.

(19) The risk of flame formation, e.g. as a stationary flame, can furthermore be reduced or suppressed by means of additive injection. By means of the additive injection, possible ignition sources, e.g. solid deposits, are desensitized.

(20) In the embodiment shown here, the insert 13 acting as a flame arrester is fixed by means of a holder 37, wherein a duct 39, through which a liquid additive, e.g. a white oil, polyolefin oil or silicone oil, can be fed in, is formed in the holder 37. Branching off from duct 39 are nozzles 41, through which the liquid additive is injected into the second annular gap 19. In this case, the nozzles 41 can be in the form of bores in the holder 37. Injection of the liquid additive into the first annular gap 15 or the gas-carrying duct 5 upstream of the insert 13 acting as a flame arrester is not desired since the liquid additive would flow only very slowly through the sintered layers and would thus collect in the first annular gap 15 and flood the latter. This can lead to malfunctioning of the ejector nozzle.

(21) If, as illustrated in FIG. 2, the insert 13 acting as a flame arrester is embodied in the form of a disk, it is possible, for example, to form a duct for the supply of the additive around the outside of the ejector nozzle and to inject the liquid additive into the region downstream of the insert 13 acting as a flame arrester through bores in the outer wall of the gas-carrying duct 5 downstream of the insert 13 acting as a flame arrester, said bores being connected to the externally formed duct for supplying the additive.

LIST OF REFERENCE SIGNS

(22) 1 ejector nozzle 2 liquid-carrying duct 5 gas-carrying duct 7 outlet opening 9 opening of the gas-carrying duct 5 into the liquid-carrying duct 3 11 diameter constriction 13 insert acting as a flame arrester 15 first annular gap 17 outer wall 19 second annular gap 21 inner wall 23 disk 25 supporting layer 27 first sintered layer 29 second sintered layer 30 packing elements 31 temperature sensor 33 groove 35 bore 37 holder 39 duct 41 nozzle