Liquid separator for separating liquid from gas and heat exchanger, provided with such a liquid separator

Abstract

Liquid separator (2) for separating a liquid from a gas, characterised in that the liquid separator (2) is constructed from several packages (14) of substantially plate-shaped liquid separation elements (15), extending substantially parallel to each other and oriented vertically during use of the liquid separator (2), which packages (14) are stacked vertically on top of each other during use of the liquid separator (2), wherein, underneath each package (14), a liquid collector (19) is placed having a reservoir (20) to pass through the liquid separation elements (15) for collecting liquid, separated by the liquid separation elements (15) from the respective package (14) and for discharging it to a discharge chamber (21), provided for that purpose.

Description

[0001] Liquid separator for separating liquid from gas and heat exchanger, provided with such a liquid separator .

[0002] The present invention relates to a liquid separator for separating a liquid from a gas .

[0003] More specifically, the invention is intended to separate and discharge the liquid in the cooled gas after cooling the gas using a heat exchanger with the liquid separator .

[0004] It is known that in compressor installations , gas at a low pressure , for example ambient air, is compressed into a gas at a higher pressure .

[0005] During this process , heat is generated, such that the compressed gas has a higher temperature than desired and therefore needs to be cooled .

[0006] A compressor installation often contains several successive compressor elements , or compression stages , in which the gas is compressed in different steps .

[0007] The gas is cooled both between the different compression stages and after the last compression stage .

[0008] This cooling occurs between the compression stages to increase the efficiency of the next compression stage .

[0009] After the final compression stage , cooling takes place to ensure that the compressed gas supplied has the desired temperature .

[0010] It is further known that when compressed gas is cooled, liquid present in the gas can condense in the form of vapour .

[0011] This liquid in the compressed gas can cause problems in the next compression stage or in the consumer network .

[0012] It is therefore important to remove this moisture or condensate from the compressed gas before it flows to the next compression stage or to the consumer network .

[0013] To cool the compressed gas and to remove moisture from the cooled gas , several solutions are already known .

[0014] A first solution consists of a heat exchanger with a cooler to cool the compressed gas , wherein a liquid separator is provided external to the heat exchanger , for example of the cyclone type .

[0015] Such cyclone-type liquid separators result in relatively large charge differences , resulting in pressure losses .

[0016] There are also liquid separators that use gravity to separate condensate from the air stream .

[0017] Although less pressure losses are generated here , they are not efficient at high airflow rates . As a result , they have to be embodied relatively large .

[0018] Heat exchangers provided with a cooling section and an integrated liquid separator are also known, as described in BE 1 . 015 . 880 .

[0019] The liquid separator comprises an array of corrugated vertical walls , which is placed next to the cooling section of the heat exchanger .

[0020] The advantage of such a heat exchanger is that it can not only be manufactured in a compact and relatively inexpensive manner, but it can also be easily fitted or integrated into a compressor device .

[0021] The additional charge loss that would normally occur between the connection of the heat exchanger to the condensate separator is also eliminated when the heat exchanger and the condensate separator are connected to each other as two separate components .

[0022] Such a heat exchanger is used in a horizontal position, wherein the heat exchanger extends in a horizontal plane and the heat exchanger is placed, for example , at the top of the compressor unit , near the roof .

[0023] The height of the heat exchanger , i . e . the dimensions in vertical sense , is limited in this position . As a result , the corrugated vertical walls , which are placed next to the cooling section, are also limited in height .

[0024] This means that the condensate , separated by the corrugated vertical walls , only has to travel a limited distance , at most equal to the height of these walls , before it can end up in a designated liquid collector .

[0025] However , not all compressor installations allow the heat exchanger to be integrated at the top and in a horizontal position in the compressor installation .

[0026] Sometimes , due to lack of space or other limitations or constraints , the heat exchanger must be placed in a vertical position, wherein the heat exchanger is tilted 90 ° , such that the heat exchanger extends in a vertical plane .

[0027] A disadvantage of such a heat exchanger with integrated liquid separator is that it cannot be placed in a vertical position .

[0028] In principle , it does not make much difference for the cooling section of the heat exchanger if it extends in a vertical plane instead of a horizontal plane .

[0029] However , tilting the heat exchanger over 90 ° means that the vertical walls also have to be tilted or rotated over 90 ° .

[0030] This means that the liquid, separated by the walls , can no longer be separated by gravity because the walls now extend horizontally .

[0031] The walls could be moved back into a vertical position to remedy this , wherein the walls extend along the full height of the heat exchanger , the height of which, by tilting over 90 ° , is now much higher than in the traditional horizontal position . Hence , this also means that the condensate , separated by the walls , and in particular the condensate , separated at the top of these walls , has to travel a much longer distance before it ends up in the drain and can be discharged .

[0032] As a result , at least some of the liquid droplets formed will be carried along by the cooled compressed gas , which flows through the walls at a relatively high speed, and will end up back in the compressed gas .

[0033] This means that , in this vertical position, the same efficiency in separating the liquid can never be achieved as in the horizontal position of such a heat exchanger .

[0034] The present invention aims to overcome at least one of the aforementioned and other disadvantages by providing a liquid separator which can be placed in the vertical position without maj or loss of efficiency in the separation of liquid .

[0035] The present invention relates to a liquid separator for separating a liquid from a gas , characterized in that the liquid separator is constructed from several packages of substantially plate-shaped liquid separation elements , extending substantially parallel to each other and oriented vertically during use of the liquid separator , which packages are stacked vertically on top of each other during use of the liquid separator, wherein, underneath each package , a liquid collector is placed having a reservoir for collecting liquid, separated by the liquid separation elements from the respective package and for discharging it to a discharge chamber , provided for that purpose .

[0036] An advantage is that , by providing stacked packages of liquid separation elements , with a liquid collector underneath each package , the condensate , separated by the liquid separation elements , has to travel a limited distance before it ends up in the reservoir .

[0037] Once the liquid enters the reservoir , it cannot be carried back by the gas flow .

[0038] Since the condensate only has to travel a limited distance before it ends up in the reservoir , this means that , once the condensate is formed, it will end up in the reservoir very quickly, making the chance virtually zero that the condensate is carried away by the gas flow .

[0039] The efficiency of a vertical heat exchanger with such a liquid separator is equivalent to the known horizontal heat exchangers with liquid separator .

[0040] In a practical embodiment , the discharge chamber is formed as a discharge tube , extending over at least a portion of the height of the liquid separator , on a side of the liquid separator extending parallel to the flow direction of the gas through the liquid separator .

[0041] By providing the discharge chamber not only at the bottom of the liquid separator, but by allowing it to extend over the height of the liquid separator and this in combination with the liquid collectors , the separated condensate can be discharged at various points .

[0042] The discharge chamber shall be located on a side of the liquid separator that extends between the inlet and the outlet of the liquid separator . That is , the discharge chamber shall not be located on a side of the liquid separator where either the inlet or the outlet is located .

[0043] According to a preferred feature of the invention, the liquid collector is constructed as a vessel serving as the reservoir, having a top wall and a bottom, wherein the top wall is provided with holes or passages to allow the liquid, separated by the liquid separation elements , to drain into the reservoir .

[0044] The holes or passages in the top wall will ensure that the condensate , which is separated by the overlying package and then flows down via the liquid separation elements up to said top wall , can end up in the vessel or reservoir .

[0045] Once the condensate has reached the vessel , it is shielded from the gas flow by the vessel . This means that it can no longer be carried away by the gas flow, or, in other words , once the condensate has end up in the vessel , the condensate has already effectively been separated .

[0046] Preferably, when the liquid separator is in use , the bottom of the vessel extends at an angle to the horizontal plane and slopes downwards towards the discharge chamber .

[0047] The slope of the bottom will ensure that all separated condensate is quickly and smoothly led to the discharge chamber under the influence of gravity .

[0048] In this case , the liquid separator vessel may have a number of upright sides , wherein the vessel is provided with a passage in a first side of the upright sides near the bottom of the reservoir, which said first side is directed towards said discharge chamber .

[0049] The invention also relates to a heat exchanger with a liquid separator according to the invention, wherein the heat exchanger further comprises a cooling section and a separation section, wherein a cooler is incorporated into the cooling section for cooling the gas with an inlet for the gas to be cooled and an outlet for the cooled gas , and wherein said liquid separator is incorporated into the separation section for separating liquid from the cooled gas with an inlet and an outlet for the cooled gas , wherein a cooler outlet element is provided between the cooling section and the separation section, which connects the outlet of the cooler to the inlet of the liquid separator .

[0050] With the aim of better demonstrating the characteristics of the invention, some preferred embodiments of a liquid separator and a heat exchanger with such a liquid separator according to the invention are described below, by way of example without any limiting character, with reference to the accompanying drawings , in which :

[0051] Figure 1 shows schematically and in perspective a heat exchanger with liquid separator according to the invention;

[0052] Figure 2 shows the heat exchanger with liquid separator of Figure 1 , but with a partial cut-away of a side ;

[0053] Figure 3 shows a schematic and perspective view of the inside of the liquid separator from Figures 1 and 2 ;

[0054] Figure 4a shows schematically and in perspective a liquid collector from Figure 3 ;

[0055] Figure 4b shows an alternative embodiment of the fluid collector of Figure 4a;

[0056] Figure 5a schematically shows a view according to arrow F5 in Figure 3 ;

[0057] Figure 5b shows a detail from Figure 5a .

[0058] In Figure 1 , a heat exchanger 1 with liquid separator 2 according to the invention is schematically shown .

[0059] In Figure 2 , the same heat exchanger 1 is shown, wherein, in this case, a portion of the housing 3a , 3b, 3c was omitted .

[0060] According to the invention, the heat exchanger 1 with liquid separator 2 comprises a cooling section 4 and a separation section 5 .

[0061] A cooler 6 is incorporated into the cooling section 4 to cool the gas .

[0062] The cooler 6 has an inlet 7 for gas to be cooled, which is typically connected or can be connected to the outlet of a compressor or compressor element for receiving the warm or hot gas from this compressor or compressor element . The cooler 6 is also provided with an outlet 8 for cooled gas which has cooled after passing through the cooler 6 .

[0063] In this case , the cooler 6 is an air-cooled cooler , which means that air is used as a cooling medium to cool the gas .

[0064] The liquid separator 2 is incorporated into the separation section 5 to separate liquid from the cooled gas .

[0065] The liquid separator 2 comprises an inlet 9 and an outlet 10 for the cooled gas .

[0066] As can be seen in Figures 1 and 2 , between the cooling section 4 and the separation section 5 , or thus between the cooler 6 and the liquid separator 2 , a cooler outlet element 11 is provided, which connects the outlet 8 of the cooler 6 to the inlet 9 of the liquid separator 2 .

[0067] The cooler outlet element 11 will thus guide the gas from the outlet 8 of the cooler 6 to the inlet 9 of the liquid separator 2 .

[0068] In the example shown, but not necessary for the invention, the outlet 8 of the cooler 6 is at an angle to the inlet 9 of the liquid separator 2 . Or, more precisely, the direction of the gas flow leaving the cooler 6 via the outlet 8 is different from the direction the gas flow must have in order to flow into the latter via the inlet 9 of the liquid separator 2 .

[0069] As can be seen in Figures 1 and 2 , in the example shown, the cooling section 4 and the separation section 5 each have their own housing 3a and 3c, respectively, as does the cooling outlet element 11 , namely housing 3b .

[0070] It is not excluded for the invention that the heat exchanger 1 with liquid separator 2 is provided with one housing 3a, 3b, 3c in which the cooling section 4 , the separation section 5 and the cooler outlet element 11 are provided .

[0071] According to the invention, the liquid separator 2 extends in a vertical plane during use .

[0072] This means that the largest dimensions extend in a vertical plane .

[0073] ' During use ' means : when the liquid separator 2 or the heat exchanger 1 is installed for use and therefore not during, for example , the production or transport of the liquid separator 2 or the heat exchanger 1 .

[0074] When reference is made to ' vertical ' in the following, this refers to the vertical sense or the dimension that extends vertically during use of the liquid separator 2 or heat exchanger 1 .

[0075] As can be seen in Figure 1 , the cooler 6 is shaped as a beam of height H , length L and width B, wherein the height H and length L are the largest dimensions . The height H extends in the vertical plane , wherein the width B and the length L extend in the horizontal plane . In this way, the heat exchanger 1 stands upright , as it were . This is in contrast to the known heat exchangers with integrated liquid separator that extend in a horizontal plane and therefore lie flat , as it were .

[0076] As a result , the largest side wall 13 of the cooler 6 also extends vertically, i . e . stands upright . This is also the plane through which the cooling gas will flow, i . e . the cooling gas flows perpendicular to this largest side wall 13 , while the gas to be cooled will flow through the cooler 6 parallel to this side wall 13 - in the figure from the right , where the inlet 7 is located, to the left , where the outlet 8 is located .

[0077] Due to the construction or structure of the heat exchanger 1 , the liquid separator 2 will also extend in a vertical plane .

[0078] According to the invention, the liquid separator 2 is constructed from several packages 14 of substantially plateshaped liquid separation elements 15 , extending substantially parallel to each other and oriented vertically during use of the heat exchanger 1 .

[0079] In Figure 2 , and in particular in Figure 3 , these packages 14 are clearly visible .

[0080] In the figures shown, there are five packages 14 , but there could be more or less than five packages 14 .

[0081] According to the invention, and as shown in Figures 2 and 3 , these packages 14 are stacked vertically on top of each other when the liquid separator 2 is in use , i . e . when the liquid separator 2 extends in a vertical plane .

[0082] The liquid separation elements 15 are configured as corrugated plates on which transversely extending hookshaped ribs 16 are provided, which form vertical channels 17 that extend over the entire or almost the entire height of the liquid separation elements 15 .

[0083] The channels 17 are located on both sides of the corrugated plates , wherein they are placed alternately on one side and on the other side , as shown in Figure 3 .

[0084] The vertical channels 17 have a substantially semicircular cross-section, but this is not necessary for the invention, wherein the open side is directed towards the direction of the incoming gas flow .

[0085] In the example shown, each liquid separation element 15 has four such ribs 16 with associated channels 17 and each package 14 has nine liquid separation elements 15 , but this is not necessary for the invention .

[0086] The number of channels 17 and the number of liquid separation elements 15 will depend on the dimensioning of the liquid separator 2 and / or heat exchanger 1 and its properties .

[0087] In Figure 5a , it is clearly visible that the outermost liquid separation elements 15 ' of each package 14 , i . e . those located at the edges of the package 14 and are located against the walls 18 of the liquid separator 2 , are only partial liquid separation elements 15 ' , wherein said channels 17 or ribs 16 , directed towards the walls 18 , have been removed or are missing from these liquid separation elements 15 ' . Or, in other words , the ribs 16 on the outermost liquid separation elements 15 ' , located on a side facing away from the other liquid separation elements 15 , are missing or have been removed . In these outermost liquid separation elements 15 ' , the channels 17 are therefore only located on one side of the liquid separation element 15 ' .

[0088] This is provided to avoid dead zones in the packages 14 between said walls 18 of the liquid separator 2 and the liquid separation elements 15 ' which are thus inaccessible to cooled gas .

[0089] Furthermore , according to the invention, a liquid collector 19 is placed underneath each package 14 with a reservoir 20 to collect condensate or liquid, separated from the respective package 14 by the liquid separation elements 15 and to discharge it to a discharge chamber 21 , provided for that purpose .

[0090] In this case , the latter is formed as a discharge tube 21 which extends over at least a part of the height of the liquid separator 2 , and can be seen in Figures 1 and 3 .

[0091] In the example shown, the discharge tube 21 extends over the entire height of the liquid separator 2 .

[0092] The discharge chamber 21 is , in the example of the figures , but not necessarily for the invention, located on a wall 18 of the liquid separator 2 which extends parallel to the direction of flow of the gas through the liquid separator 2 .

[0093] Or, in other words , the wall 18 extending between the inlet 9 and the outlet 10 of the liquid separator 2 . In other words , the discharge chamber 21 is not located on the side of the liquid separator 2 where the inlet 9 or the outlet 10 is located .

[0094] This wall 18 of the liquid separator 2 is , in this case , formed by a partition wall 22 between the stacked packages 14 of liquid separating elements 15 and the discharge chamber 21 and provides a seal between the two . In Figure 3 , this partition wall 22 is clearly visible .

[0095] The partition wall 22 will ensure that condensate , which has been separated, is shielded from the gas stream of cooled gas flowing through the liquid separator 2 , thus preventing condensate or condensate droplets from being again taken up into the gas stream .

[0096] The fluid collectors 19 are constructed as a vessel 24 which serves as the reservoir 20 . They are shown in more detail in Figures 4a to 5b .

[0097] In this case , the liquid collectors 19 have the shape of a kind of tray, wherein they have a limited height .

[0098] The vessel 24 comprises a top wall 25 , a bottom 26 and four upright sides 27a , 27b , 27c, 27d . Holes 28 or passages are provided in the top wall 25 to allow the liquid or condensate , separated by the liquid separation elements 15 , to be drained into the reservoir 20 and collected there .

[0099] The liquid separation elements 15 are , as it were , placed on the top wall 25 , such that the condensate that is captured by the liquid separation elements 15 , and in particular by the channels 17 , flows down to the top wall 25 by gravity, and then ends up in the reservoir 20 underneath the top wall

[0100] 25 via these holes 28 .

[0101] In order to discharge the liquid to the discharge chamber 21 , the vessel 24 of the liquid collector 19 is provided with a passage 29 in a first upright side 27d near the bottom

[0102] 26 of the vessel 24 , said first side 27d being directed towards said discharge chamber 21 .

[0103] Said first side 27d will , in this case , form part of or coincide with said partition wall 22 .

[0104] Alternatively, it is also possible that this first side 27d is located adj acent to or against said partition wall 22 and that the partition wall 22 is provided with a corresponding passage .

[0105] In the embodiment of Figure 4a, the bottom 26 of the vessel 24 extends at an angle to the horizontal plane , in use of the liquid separator 2 , and slopes towards the discharge chamber 21 . That is to say, the bottom 26 slopes towards said passage 29. This will help the condensate , discharged into the reservoir 20 , to flow by gravity towards said passage 29 and then further to the discharge chamber 21 .

[0106] In Figure 4b , an alternative embodiment is shown for the bottom 26 , wherein this bottom 26 slopes both to the first side 27d and to the opposite side 27b . A passage 29 will also be provided in the opposite side 27b .

[0107] In such an embodiment , a discharge chamber 21 will be provided on this opposite side 27b or a channel or conduit will be provided, running from the passage 29 in the opposite side 27b to said discharge chamber 21 on the first side 27d .

[0108] The operation of the liquid separator 2 is very simple and as follows .

[0109] Gas , for example compressed air from a compressor, compressor element or compressor device , enters the heat exchanger 1 with liquid separator 2 via the inlet 7 of the cooler 3 in the cooling section 4 .

[0110] This compressed gas , which has to be cooled, flows through the cooler 6 in the cooling section in the direction of the arrows P in Figure 1 .

[0111] The arrows P in Figure 1 show the path, taken by the compressed gas in the heat exchanger 1 . The compressed gas flows through the cooler 6 from right to left in the example of Figure 1 .

[0112] At the same time , the heat exchanger , more specifically the cooler 2 , is flowed through with a cooling gas . This cooling gas has the purpose of extracting heat from the compressed gas .

[0113] The cooling gas flows through the cooler 6 in a direction perpendicular to the compressed gas , as shown by arrows R .

[0114] As it passes through cooler 6 , the compressed gas will be cooled by transferring its heat to the cooling gas in a known manner .

[0115] When the compressed gas reaches the outlet 8 of cooler 6 , it will have the desired temperature .

[0116] After passing through the cooler 6 , the cooled compressed gas enters the cooler outlet element 11 .

[0117] As flow passes through the packages 14 , the channels 17 will capture condensate droplets from the gas stream.

[0118] These will flow down via the channels 17 and will be collected on the top walls 25 of the liquid collectors 19 .

[0119] The cooled compressed gas will then leave the liquid separator 2 via the outlet 10 .

[0120] The condensate that ends up on the top wall 25 of the liquid collectors will end up in the vessel 24 through the holes 28 in this top wall 25 and will be guided through the sloping bottom 26 to the passage 29 and through the latter into the discharge chamber 21 .

[0121] For example , a discharge pipe 30 is connected to this discharge chamber 21 to allow further discharge of the condensate .

[0122] When the cooled compressed gas leaves the liquid separator 2 through the outlet 10 , it will be free of condensate or moisture and it can be passed to a subsequent compressor stage or compressed gas consumer network .

[0123] The present invention is by no means limited to the embodiments , described by way of example and shown in the figures , but a liquid separator or heat exchanger with liquid separator according to the invention can be realised in all kinds of shapes and sizes without departing from the scope of the invention as defined in the claims .

Claims

Claims .1.- Liquid separator (2) for separating a liquid from a gas, characterised in that the liquid separator (2) is constructed from several packages (14) of substantially plate-shaped liquid separation elements (15) , extending substantially parallel to each other and oriented vertically during use of the liquid separator (2) , which packages (14) are stacked vertically on top of each other during use of the liquid separator (2) , wherein, underneath each package (14) , a liquid collector (19) is placed having a reservoir (20) for collecting liquid, separated by the liquid separation elements (15) from the respective package (14) and for discharging it to a discharge chamber (21) , provided for that purpose.2.- Liquid separator according to claim 1, characterised in that the discharge chamber (21) is formed as a discharge tube (21) , extending over at least a portion of a height of the liquid separator (2) , on a side (18) of the liquid separator (2) , extending parallel to a flow direction of the gas through the liquid separator (2) during use of the liquid separator ( 2 ) .3.- Liquid separator according to claim 2, characterised in that said side (18) of the liquid separator (2) is formed by a partition wall (22) between the stacked packages (14) of liquid separating elements (15) and the discharge chamber (21) which provides a seal between the two.4.- Liquid separator according to any one of the preceding claims, characterised in that the liquid collector (19) is constructed as a vessel (24) which serves as the reservoir (20) , having a top wall (25) and a bottom (26) , wherein the top wall (25) is provided with holes (28) or passages to allow the liquid, separated by the liquid separation elements (15) , to be drained into the reservoir (20) .5.- Liquid separator according to claim 4, characterised in that the vessel (24) of the liquid collector (19) has a number of upright sides (27a, 27b, 27c, 27d) between the top wall (25) and bottom (26) , wherein the vessel (24) is provided with a passage (29) in a first side (27d) of these upright sides (27a, 27b, 27c, 27d) near the bottom (26) of the reservoir (20) , which said first side (27d) is directed towards said discharge chamber (21) .6.- Liquid separator according to one of the preceding claims 4 or 5, characterised in that the bottom (26) of the vessel (24) in use of the liquid separator (2) extends at an angle to the horizontal plane and slopes towards the discharge chamber (21 ) .7.- Liquid separator according to any one of the preceding claims, characterised in that the liquid separation elements (15) are configured as corrugated plates on which transversely extending hook-shaped ribs (16) are provided which form vertical channels (17) which extend over a full or almost full height of the liquid separation elements (15) .8.- Heat exchanger with a liquid separator (2) according toany one of the preceding claims, wherein the heat exchanger (1) is further provided with a cooling section (4) and a separation section (5) , wherein a cooler (6) is incorporated into the cooling section (4) for cooling the gas with an inlet (7) for the gas to be cooled and an outlet (8) for the cooled gas, and wherein said liquid separator (2) is incorporated into the separation section (5) for separating liquid from the cooled gas with an inlet (9) and an outlet (10) for the cooled gas, wherein a cooler outlet element (11) is provided between the cooling section (4) and the separation section (5) which connects the outlet (8) of the cooler (6) to the inlet (9) of the liquid separator (2) .

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