Condensate separators for exhaust gas measuring systems

Abstract

Condensate separator for an exhaust gas measuring system, with a housing (12) with a condensate drain opening (22), a cooled inlet line (30) for introducing a fluid into the housing (12), wherein the inlet line (30) opens into the inlet opening (28) formed in the housing (12), and a gas outlet nozzle (35) which has a gas inlet (38) and a gas outlet (40), wherein the gas outlet nozzle (35) leads into a gas outlet line (50), characterized by the fact that the cross-sectional area of ​​the gas inlet (38) of the gas outlet nozzle (35) is larger than the cross-sectional area of ​​the gas outlet (40) of the gas outlet nozzle (35), wherein the gas outlet nozzle (35) extends outwards from an upper base surface (18) of the housing (12).

Description

[0001] The invention relates to a condensate separator for an exhaust gas measuring system, comprising a housing with a condensate drain opening, a cooled inlet line for introducing a fluid into the housing, wherein the inlet line opens into an inlet opening formed in the housing, and a gas outlet nozzle which has a gas inlet and a gas outlet, wherein the gas outlet nozzle opens into a gas outlet line.

[0002] Condensate separators are known from the prior art and serve to separate water from fluids, especially gases or gas mixtures. In exhaust gas measurement systems, condensate separators are used to remove water from sample gas streams containing water or water vapor. During the combustion of fuels, water vapor is formed, which is present as a component in the exhaust gas stream, with the fluid being saturated with water vapor at the dew point. If the temperature of the fluid is lowered below the dew point, the water vapor condenses, and the condensate exists in the liquid phase. On the one hand, such condensation in the measuring instrument can lead to, for example, spectroscopic instruments delivering erroneous results; on the other hand, the components of the exhaust gas measurement system become contaminated, thus reducing the service life of the measuring instruments, for example, through corrosion.

[0003] Lowering the fluid temperature below the dew point is therefore used to specifically reduce the water vapor content in the exhaust gas and to separate the condensate in front of the measuring device in order to dry the measuring gas.

[0004] For this purpose, the measuring gas is passed through a cooler into a condensate separator, the condensate is separated from the fluid in the condensate separator and the separated condensate is directed into a condensate container, from which the condensate can be drained at intervals or continuously by means of a drain valve.

[0005] DE 37 06 941 A1 discloses a device for cooling gases. The cooler has a container filled with coolant. An inlet line runs through the coolant-filled container and opens into a condensate separator, through which the fluid to be cooled flows. The condensate separator consists of a cylindrical section and an adjoining frustoconical section, the frustoconical section tapering downwards and opening into a condensate drain. At the end of the condensate separator opposite the condensate drain, a dip tube extends into the condensate separator, serving as a gas outlet nozzle and opening into a gas discharge line. The gas, dried by the condensate separation process, flows out of the condensate separator through the dip tube.

[0006] A disadvantage of the design described in DE 37 06 941 A1 is that the gas flow rate exiting through the gas outlet nozzle, due to its high flow velocity, carries along already separated condensate and thus transports the condensate via the immersion tube from the condensate separator and to the measuring instruments.

[0007] Furthermore, DE 741 37 70 U discloses a condensate separator with a cylindrical housing in which a frustoconical dip tube projects into the housing to just before a baffle plate, over which the condensate is to flow away. The inlet is arranged radially opposite the outer surface of the dip tube, so that the dip tube is subject to flow.

[0008] US Patent 2006 / 0130653 A1 further discloses a condensate separator in which an inlet is also arranged at the upper end of a cylindrical housing, which is radially opposite a frustoconical immersion tube. This condensate separator additionally has a spray device by which solid components are to be bound by the liquid.

[0009] US Patent 5,466,270 A discloses a cyclone-shaped condensate separator whose dip tube, slightly flared at the lower end, extends into the conical section of the cyclone. The inlet is located at the top of the cyclone.

[0010] These well-known condensate separators all have the disadvantage that the mixed flow reaches the rear wall of the immersion tube, where condensate settles, which, however, can be carried upwards from the lower edge of the immersion tube.

[0011] The task therefore arises to further develop a condensate separator in such a way that the separated condensate is not carried along to the measuring instruments by the gas volume flow.

[0012] This problem is solved by a control cabinet for exhaust gas measurement systems with the features of main claim 1.

[0013] Because the cross-sectional area of ​​the gas inlet of the gas outlet nozzle is larger than the cross-sectional area of ​​the gas outlet of the gas outlet nozzle, and because the gas outlet nozzle extends outwards from an upper base surface of the housing, the flow velocity of the gas volume flow at the gas inlet of the gas outlet nozzle is reduced. This prevents condensate from being carried along by the gas volume flow into the gas outlet nozzle and towards the measuring instruments in a simple and cost-effective manner. The gas outlet nozzle can be manufactured during the housing production process, thus reducing manufacturing and assembly costs.

[0014] Preferably, the inlet opening is arranged on a side wall of the housing, with the inlet line opening tangentially into the housing and the fluid being introduced tangentially into the housing. The housing is preferably cylindrical. The tangential introduction of the fluid causes it to enter a circular orbit, whereby the centrifugal force forces the condensate outwards against the side wall of the condensate separator, slows it down, and adheres to the side wall, thus separating the condensate from the fluid flow. The separated condensate flows downwards along the side wall of the condensate separator to the condensate drain opening. The dried gas then flows out of the condensate separator through the gas outlet nozzle. In this way, the condensate is separated from the fluid in a cost-effective and simple manner.

[0015] Preferably, the gas outlet nozzle has a frustoconical section between the gas inlet and the gas outlet, thereby avoiding the dead volume that occurs with a discontinuous cross-sectional transition. By avoiding the dead volume in the gas outlet nozzle, the gas lines in the exhaust gas measurement system can be reduced in size, and the exhaust gas flow rate required for the measurements can be reduced.

[0016] In a preferred embodiment, the gas outlet nozzle has a step between the gas inlet of the gas outlet nozzle and the gas outlet of the gas outlet nozzle, whereby the change in cross-section between the gas outlet of the gas outlet nozzle and the gas inlet can be provided in a simple way.

[0017] In an advantageous embodiment, the cross-sectional area of ​​the gas inlet is twice as large as the cross-sectional area of ​​the gas outlet. This ratio of the cross-sectional areas of the gas inlet and outlet nozzles minimizes the amount of previously separated condensate carried along by the gas flow into the outlet nozzle.

[0018] Preferably, the inlet line runs in a spiral shape through a cooler. In the cooler, the fluid cools down and the water vapor present in the fluid condenses, with the condensate being carried away by the fluid flow. Due to the spiral design of the inlet line, more heat can be dissipated from the fluid, as a larger surface area of ​​the inlet line is surrounded by the cooling medium.

[0019] In a preferred embodiment, the diameter of the inlet line corresponds at least to the diameter of a condensing droplet of the condensate. In this way, the fluid flow rate generated by a pump is always guaranteed, while blockage of the inlet line and pressure build-up in the inlet line caused by the condensate are prevented.

[0020] Preferably, the housing comprises a cylindrical section containing the inlet opening and a frustoconical section adjoining the cylindrical section, containing the condensate drain opening. In the cylindrical section, the fluid is introduced into the condensate separator and circulated in a cylindrical path. In the frustoconical section adjoining the cylindrical section, the fluid flow velocity and thus the centrifugal force acting on the condensate are increased, thereby increasing the amount of condensate separated from the fluid. This prevents condensate from dripping from the inlet opening onto a smooth surface of the housing below, which could cause splashing and carry water towards the gas outlet.

[0021] This creates a condensate separator for exhaust gas measuring systems, which prevents the separated condensate from being carried along by the gas flow into the gas outlet nozzle in a simple and cost-effective way, thereby avoiding contamination of the measuring instruments, measurement inaccuracies and corrosion-related failures of measuring instruments.

[0022] The exemplary embodiments of a condensate separator according to the invention for exhaust gas measuring systems are shown in the figures and are described below. Fig. Figure 1 shows a condensate separator with a first embodiment of the gas outlet nozzle, and Fig. Figure 2 shows a condensate separator with a gas outlet nozzle design according to the invention.

[0023] Fig. Figure 1 shows a condensate separator 10 for a [unclear] in the Fig. Figure 1 shows an exhaust gas measuring system (not shown) with a housing 12, which is composed of a cylindrical housing section 14 and a frustoconical housing section 16. The cylindrical housing section 14 has a closed upper base 18 and an open lower base 20, with the frustoconical housing section 16 adjoining the open lower base 20. The frustoconical housing section 16 tapers downwards, so that the diameter of the frustoconical housing section 16 decreases from the open lower base 20 of the cylindrical housing section 14 to a condensate drain opening 22 located at the lower end of the frustoconical housing section 16. A drain line 24 connects to the condensate drain opening 22, which connects the condensate separator 10 to, for example, a condensate collection tray (not shown in the figure).

[0024] An inlet opening 28 is formed on the circumferential side wall 26 of the cylindrical housing section 14, which is connected to an inlet line 30, wherein the inlet line 30 is spirally shaped and runs through a cooler 32.

[0025] A dip tube 36, connected to a gas outlet line 50, extends through the closed upper base 18 of the cylindrical housing section 14 into the housing 12, forming a gas outlet nozzle 35. The dip tube 36 has a gas inlet 38 located in the housing 12 and a gas outlet 40 located in the horizontal plane of the upper base 18 of the cylindrical housing section 14 and directed towards the gas outlet line 50.

[0026] According to the invention, the cross-sectional area of ​​the gas inlet of the immersion tube 36 or the gas outlet nozzle 35 is larger than the cross-sectional area of ​​the gas outlet 40 of the immersion tube 36 or the gas outlet nozzle 35. For the change in cross-section between the gas inlet 38 and the gas outlet 40, the immersion tube 36 has a frustoconical section 42, which adjoins a cylindrical section 44. The immersion tube 36 is fixedly arranged via the cylindrical section 44 on the upper base 18 of the cylindrical housing section 14 and is immersed in the housing 12 with the cylindrical section 44. The frustoconical section 42 adjoins the cylindrical section 44 immersed in the housing 12, with the frustoconical section 42 tapering from the gas inlet 38 to the transition into the cylindrical section 44. Alternatively, the immersion tube 36 could have a step instead of the frustoconical section 42.

[0027] Fig. Figure 2 shows a condensate separator 10 with a housing 12, which, as in Fig. 1 also consists of a cylindrical housing section 14 with an inlet opening 28 formed on the circumferential side wall 26 of the cylindrical housing section 14 and a frustoconical housing section 16 with a condensate drain opening 22. The cylindrical housing section 14 has an upper base surface 18 and an open lower base surface 20, with the frustoconical housing section 16 adjoining the open lower base surface 20. The frustoconical housing section 16 tapers downwards and has the condensate drain opening 22 at its lowest point.

[0028] In contrast to the one in Fig. In the embodiment shown in Figure 1, the gas outlet nozzle 35 does not extend into the housing 12, but rather connects to the upper base surface 18 of the cylindrical housing section 14. The gas outlet nozzle 35 has a gas inlet 38 and a gas outlet 40 fluidically connected to a gas outlet line 50, wherein the diameter of the gas inlet 38 corresponds to the diameter of the upper base surface 18 of the cylindrical housing section 14 and tapers from the upper base surface 18 to the gas outlet 40 of the gas outlet nozzle 35. Thus, according to the invention, the cross-sectional area of ​​the gas inlet 38 is larger than the cross-sectional area of ​​the gas outlet 40.

[0029] The condensate separation process occurs in both cases. Fig. 1 and Fig.The process is identical to that described in the two descriptions. In the condensate separation process, the fluid first flows through the cooled inlet line 30 to the inlet opening 28. The inlet line 30 is cooled by the cooler 32, which is a pot-shaped container filled with cooling medium, through which the spirally shaped inlet line 30 runs. In this way, the fluid is cooled below its dew point, causing the water vapor contained in the fluid to condense. The fluid flow carries the condensate along with it and transports it into the housing 12. The fluid, containing the condensed condensate, flows tangentially into the housing 12 through the inlet opening 28 formed in the cylinder wall 26. Due to the cylindrical shape of the housing 12, the fluid and the condensate circulate along the cylinder wall 26 of the housing 12.Due to the higher mass of the condensate droplets, a greater centrifugal force acts upon them, causing the condensate droplets, carried along by the fluid flow, to be flung from the fluid against the cylinder wall 26, slowed down on the cylinder wall 26, and flow over the cylinder wall 26 to the condensate drain opening 22. A drain line 24 connects to the condensate drain opening 22, linking the condensate separator 10 to, for example, a condensate collection tray (not shown in the figure).

[0030] The frustoconical housing section 16 of the housing 12 serves to increase the flow velocity of the volume flow of the fluid, thereby further increasing the centrifugal force acting on the condensate droplets and thus the separation of the condensate.

[0031] The gas, thus freed from condensate, flows in the center of the housing 12 to the gas inlet 38 of the gas outlet nozzle 35. The larger cross-sectional area of ​​the gas inlet 38 compared to the gas outlet 40 of the gas outlet nozzle 35 reduces the flow velocity of the gas volume flow at the gas inlet 38, thereby preventing the already separated condensate from being carried along by the gas volume flow into the gas outlet nozzle 35.

[0032] This creates a condensate separator for an exhaust gas measuring system, which prevents the carryover of already separated condensate by the gas flow in a simple and cost-effective manner, thus avoiding contamination of the measuring instruments, measurement inaccuracies and corrosion-related failures of measuring instruments.

[0033] It should be clear that the scope of protection of the present main claim is not limited to the described embodiments.

Claims

[1] Condensate separator for an exhaust gas measuring system, comprising a housing (12) with a condensate drain opening (22), a cooled inlet line (30) for introducing a fluid into the housing (12), wherein the inlet line (30) opens into the inlet opening (28) formed in the housing (12), and a gas outlet nozzle (35) having a gas inlet (38) and a gas outlet (40), the gas outlet nozzle (35) opening into a gas outlet line (50), characterized by , that the cross-sectional area of ​​the gas inlet (38) of the gas outlet nozzle (35) is larger than the cross-sectional area of ​​the gas outlet (40) of the gas outlet nozzle (35), wherein the gas outlet nozzle (35) extends outwards from an upper base surface (18) of the housing (12). [2] Condensate separator for an exhaust gas measuring system according to claim 1, characterized bythat the inlet opening (28) is arranged on a side wall (26) of the housing (12), wherein the inlet line (30) opens tangentially into the housing (12). [3] Condensate separator for an exhaust gas measuring system according to claim 1 or 2, characterized by that the gas outlet nozzle (35) has a frustoconical section (42) between the gas inlet (38) and the gas outlet (40). [4] Condensate separator for an exhaust gas measuring system according to claim 1 or 2, characterized by that the gas outlet nozzle (35) has a step between the gas inlet (38) and the gas outlet (40). [5] Condensate separator for an exhaust gas measuring system according to one of the preceding claims, characterized by that the cross-sectional area of ​​the gas inlet (38) is twice as large as the cross-sectional area of ​​the gas outlet (40). [6] Condensate separator for an exhaust gas measuring system according to one of the preceding claims, characterized bythat the inlet line (30) runs spirally through a cooler (32). [7] Condensate separator for an exhaust gas measuring system according to one of the preceding claims, characterized by that the diameter of the inlet line (30) corresponds at least to the diameter of a condensing drop of the condensate. [8] Condensate separator for an exhaust gas measuring system according to one of the preceding claims, characterized by that the housing (12) has a cylindrical housing section (14) in which the inlet opening (28) is formed and a frustoconical housing section (16) adjoining the cylindrical housing section (14) in which the condensate drain opening (22) is formed.

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