Tube register for indirect heat exchange

Abstract

A register for the indirect heat exchange between a utility fluid containing interfering components and a heat transfer fluid has at least one tube row with at least one flow channel with a small channel width and at least one flow channel with a large channel width. Additionally, in at least one tube row there is provided at least one flow channel with a narrow section defined by a small channel width as well as a wide section defined by a large channel width. The large channel width produces a large flow velocity of the utility fluid and the small channel width produces a small flow velocity of the utility fluid.

Claims

1. A register for indirect heat exchange between a utility fluid containing interfering components and a heat transfer fluid in a heat exchanger, the register comprising: a plurality of tubes for the passage of the heat transfer fluid, the tubes extending in a vertical direction from a top of the heat exchanger to a bottom of the heat exchanger, wherein the tubes are arranged in a plurality of tube layers; and a plurality of tube rows, wherein the tube layers and the tube rows run transversely to one another, wherein the tube layers define a plurality of flow channels for the utility fluid to flow through, wherein in at least one tube row there is provided a plurality of flow channels having alternately narrow widths and wide widths such that every second flow channel has a first channel width defined by the minimum distance between adjacent tubes of the tube row and every other second flow channel has a second channel width defined by the minimum distance between adjacent tubes of the tube row, the second channel width being larger than the first channel width and retaining elements in the shape of a rod and extending substantially along the tube layers are provided only in the flow channels having the first channel width such that the tubes of the at least one tube row adjacent to the respective retaining element are fixed to the respective retaining element, or wherein in at least one tube row there is provided at least one flow channel having a first section having a channel width defined by the minimum distance between the adjacent tubes of the tube row in the first section and extending in the longitudinal direction of the tubes and having a second section having a channel width defined by the minimum distance between the adjacent tubes of the tube row in the second section and extending in the longitudinal direction of the tubes, the channel width of the second section being larger than the channel width of the first section and in the at least one tube row, retaining elements in the shape of a rod and extending substantially along the tube layers are provided only in every second flow channel such that the tubes of the at least one tube row adjacent to the respective retaining element are fixed to the respective retaining element.

2. The register according to claim 1, wherein a constant channel width is provided in at least two tube rows following one another in the flow direction of the utility fluid in at least one flow channel.

3. The register according to claim 1, wherein exactly one tube layer is fixed on at least one retaining element of the register and exactly two adjacent tube layers are fixed on at least one other retaining element.

4. The register according to claim 1, wherein the retaining elements run substantially laterally to the tube layers held by the retaining element.

5. The register according to claim 1, wherein the retaining elements between the tubes of at least one tube row located on the retaining elements have spacers for spacing the tubes located on the retaining elements and/or are formed as spacers.

6. The register according to claim 1, wherein the retaining elements are arranged in the flow channel with the first channel width and/or in the first section of the flow channel.

7. The register according to claim 1, wherein a rinse line for the supply of rinse medium is provided in at least one flow channel with the first channel width or in the first section in at least one tube row.

8. The register according to claim 7, wherein a rinse line is provided in every second flow channel in at least one tube row.

9. The register according to claim 7, wherein the rinse lines are adapted as spacers for spacing adjacent tubes of the at least one tube row.

10. The register according to claim 7, wherein the rinse lines are arranged in the flow channel with the first channel width and/or in the first section of the flow channel.

11. The register according to claim 7, wherein at least one retaining element is simultaneously formed as a rinse line, or vice versa.

12. The register according to claim 1, wherein at least one tube layer is aligned at least in sections inclined and/or curved in relation to the inflow direction of the utility fluid through the register.

13. The register according to claim 12, wherein at least two tube layers define between them a flow channel with an opening on the inlet side and an opening on the outlet side for the utility fluid in such a way that the opening on the inlet side in the inflow direction of the utility fluid in relation to the register does not overlap the opening on the outlet side.

14. The register according to claim 1, wherein in at least one tube row there is arranged at least one flow channel with alternately narrow sections and wide sections in the longitudinal direction of the tubes.

15. The register according to claim 14, wherein in at least one tube row all flow channels have alternately narrow sections and wide sections.

16. The register according to claim 14, wherein in at least one tube row flow channels are arranged next to one another at least in sections so that wide sections and narrow sections and/or second channel widths and first channel widths alternate.

17. The register according to claim 1, wherein in at least two tube rows following one another in the flow direction of the utility fluid there are provided in at least one flow channel alternately a narrow section and a wide section or alternately the second channel width and the first channel width.

18. The register according to claim 1, wherein at least individual tubes of at least one tube row are arranged in regions in a first tube layer and in regions in a second tube layer.

19. The register according to claim 18, wherein the first tube layer and the second tube layer are adjacent layers.

20. The register according to claim 18, wherein at least some of the individual tubes of at least one tube row cross one another, at least once, along the longitudinal length of the tubes.

21. The register according to claim 20, wherein substantially all tubes of at least one tube row are crossed, at least once, along the longitudinal length of the respective tubes with an adjacent tube.

22. The register according to claim 21, wherein in at least one tube row the crossing points of the tubes are arranged substantially on the same plane perpendicular to the longitudinal length of the tubes.

23. The register according to claim 21, wherein in at least one tube row adjacent tubes that do not cross one another have crossing points on different planes perpendicular to the longitudinal length of the tubes.

24. The register according to claim 23, wherein in at least one tube row adjacent tubes crossing one another define via their crossing points planes perpendicular to the longitudinal length of the tubes, which are arranged, substantially centrally, between the planes running perpendicular to the longitudinal length of the tubes, which are defined by the crossing points of further, substantially adjacent, tubes crossing one another.

25. The register according to claim 19, wherein in at least one tube row there are provided tubes formed substantially rectilinearly adjacent to tubes crossing one another.

26. The register according to claim 1, wherein in at least one tube row and/or tube layer there are provided tubes with significantly different tube diameters.

27. The register according to claim 26, wherein in at least one tube layer there are provided tubes with an identical tube diameter.

28. The register according to claim 1, wherein the tubes of the register are made of metal and/or a plastic material.

29. The register according to claim 1, wherein the tubes are formed as rigid or flexible tubes.

30. The register according to claim 1, wherein at least one tube row and/or one tube layer comprise flexible tubes as well as rigid tubes.

31. The register according to claim 1, wherein at least one tube layer is formed as a tube disc to reflect sound waves.

32. The register according to claim 31, wherein two to six tube discs are provided in the register.

33. A heat exchanger with at least one register, wherein the register is a register according to claim 1.

34. The heat exchanger according to claim 33, wherein in the flow direction of the utility fluid there is provided in front of the lower end of the register in the direction of gravity a barrier aligned transverse to the flow direction to protect the register against abrasion by particles entrained by the utility fluid.

35. The heat exchanger according to claim 33, wherein the barrier forms together with a floor of the heat exchanger a gap provided for the accelerated throughflow of the utility fluid.

36. The heat exchanger according to claim 35, wherein the height of the free gap corresponds at most to substantially the minimum interspacing between the lower end of the register and the floor of the heat exchanger.

37. The heat exchanger according to claim 33, wherein the tubes of the register have tube curvatures at the lower end of the register in the direction of gravity.

38. The heat exchanger according to claim 37, wherein in the region of the tube curvatures in at least one tube row the channel width is a maximum at least in a flow channel with the second channel width.

39. The heat exchanger according to claim 38, wherein in the region of the tube curvatures in at least one tube row the channel width is essentially zero at least in a flow channel with the first channel width.

40. A register according to claim 1, adapted for use with a heating and/or cooling gas containing interfering components.

41. The register according to claim 40, wherein the interfering components are particles or condensate.

42. The register according to claim 40, wherein the interfering component is entrained liquid.

43. The register according to claim 40, wherein a flue gas scrubber is connected upstream and/or downstream of the register.

44. The register according to claim 40, wherein the heating and/or cooling gas is flue gas.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1a shows a register of a tube bundle heat exchanger of the prior art with a square distribution, in a sectional view perpendicular to the tubes of the tube bundle,

(2) FIG. 1b shows a register of a tube bundle heat exchanger of the prior art with a triangular distribution in a sectional view perpendicular to the tubes of the tube bundle,

(3) FIG. 2 shows a detail of a first embodiment of a register according to the invention in a direction parallel to the flow direction of the utility fluid,

(4) FIG. 3 shows the detail of the register of FIG. 2 in a sectional view along the plane II-II of FIG. 2,

(5) FIG. 4 shows a further detail of the register of FIG. 2 in a direction parallel to the flow direction of the utility fluid,

(6) FIG. 5 shows a detail of a second embodiment of the register according to the invention in a sectional representation according to FIG. 3,

(7) FIG. 6 shows a detail of a third embodiment of the register according to the invention in a sectional representation according to FIG. 3,

(8) FIG. 7 shows a detail of a fourth embodiment of the register according to the invention in a viewing parallel to the flow direction of the utility fluid,

(9) FIG. 8 shows a detail of a fifth embodiment of the register according to the invention in a viewing parallel to the flow direction of the utility fluid,

(10) FIG. 9 shows a detail of a sixth embodiment of the register according to the invention in a viewing direction parallel to the flow direction of the fluid,

(11) FIG. 10 shows the floor region of a first embodiment of the heat exchanger according to the invention in a viewing direction parallel to the flow direction of the utility fluid, and

(12) FIG. 11 shows the floor region of the heat exchanger of FIG. 10 in a sectional representation along the plane IX-IX of FIG. 10.

DETAILED DESCRIPTION OF THE INVENTION

(13) Conventional types of a register that are known from the prior art are illustrated in FIGS. 1a and 1b. The tube bundle of a register of a heat exchanger illustrated in FIG. 1a has a square distribution. The tube mid-points of two adjacent tubes R of a tube row RR and of two tubes arranged flush therewith then form the corners of a square. In other words, in such a register the adjacent tubes R of a tube row RR as well as adjacent tubes R of a tube layer RL are in each case arranged at the same distance from one another. If this distance between the tube layers and the tube rows were different, this would not be a square distribution but a rectangular distribution. In this case too the distances between the tube rows and the tube layers of the register would be identical at every point of the register. Also the register then has a symmetrical structure.

(14) In a tube bundle of a register of a heat exchanger with a triangular distribution, which is illustrated in FIG. 1b, the tube layers RL are not aligned flush with one another, but are displaced with respect to one another by in each case half a tube interspacing. At every point within the register there are adjacently located three tubes R, whose mid-points lie at the vertices of a triangle and whose side edges have the same length b. This is therefore an equilateral distribution. The sides of a corresponding triangle defining the distribution could however also be of different lengths. In this case too all tube mid-points of corresponding adjacent tubes would however in each case define equal triangles. This means that registers constructed in this way are also symmetrical throughout.

(15) The tubes R, R in both a triangular distribution and in a square distribution form flow channels with a constant width. The displacement of the tube layers RL with respect to one another means however that the tubes R in a triangular distribution can be more tightly packed than the tubes R in a square distribution, without the pressure loss rising unduly. In the end an extremely symmetrical arrangement of the tubes R, R within the register of a heat exchanger is obtained both in a square distribution as well as in a triangular distribution. This means that the distribution, i.e. the tube interspacings a, b, in each section of the register of a heat exchanger are identical. Consequently there exist neither flow channels of different channel width nor flow channels that have a wide section and a narrow section.

(16) FIG. 2 shows a detail of a heat exchanger 1 that comprises a register 2 with tubes 3 aligned parallel to one another. As is illustrated for example in FIG. 3 in a horizontal section along the plane II-II of FIG. 2, the register 2 has perpendicular to the flow direction S of the utility fluid a row of tube rows 4 arranged behind one another, which in the flow direction S of the utility fluid form tube layers 5 arranged parallel to one another. The individual tubes 3 of each tube layer 5 are arranged flush behind one another in the flow direction S of the utility fluid.

(17) In the illustrated register 2 in each case two adjacent tube layers 5 define between them a flow channel 6, 6 for the flow through of the utility fluid. In this connection each flow channel 6, 6 in each tube row 4 has a channel width 7, 7 that is fixed by the interspacing of in each case adjacent tubes 3. In the case of the register 2 illustrated in FIGS. 2 and 3 the channel widths 7, 7 of each flow channel 6, 6 are constant in the flow direction S of the utility fluid. The channel width 7, 7 of the flow channels 6, 6 therefore does not change from tube row 4 to tube row 4 of the register 2. In addition the channel width 7, 7 in the illustrated embodiment is in each case aligned perpendicular to the flow direction S of the utility fluid.

(18) In each tube row 4 of the illustrated register 2 flow channels 6, 6 with a large channel width 7 and a small channel width 7 alternate. On account of the larger channel width 7 a higher flow velocity of the utility fluid is established in the corresponding flow channels 6, while on account of the smaller channel width 7 a lower flow velocity of the utility fluid is established in the remaining flow channels 6.

(19) The tubes 3 provided in the tube rows 4 illustrated in FIGS. 2 and 3 are in each case grouped in pairs and are fixed on a common rod-shaped retaining element 8 that extends parallel to the adjoining tube layers 5, i.e. in other words along the flow channel 6 of small channel width 7. In front of the register 2 the retaining elements 8 are held in the illustrated plane of the register 2 on a suspension 9 running transverse to the register. The retaining elements 8 have spacers 10, against which abut from two sides two adjacent tubes 3 of different tube layers 5. An annular element 11 surrounding the tubes 3 serves to fix in each case two adjacent tubes 3 of different tube layers 5 to a retaining element 8. Through the grouping in each case of two tube layers 5 to a retaining elements 8, the retaining elements in the illustrated register 2 are in each case provided only in every second flow channel 6.

(20) A further detail of the register 2 according to FIGS. 2 and 3 is illustrated in FIG. 4, wherein FIG. 4 illustrates a view corresponding to FIG. 2, which however shows a section in a region in which rinse lines 12 are provided for flushing and in this way removing interfering components from the register 2. For this purpose the rinse lines 12 can be arranged at different heights in the register. In any case, at least some of the rinse lines 12 are arranged relatively high in the register 2. In addition the rinse lines 12 are provided only in every second flow channel 6. In this connection the rinse lines 12 extend substantially along the whole flow channels 6 through the register 2. Furthermore it is possible, although not shown in detail, for the rinse lines 12 to be fixed to retaining elements 8.

(21) In the illustrated register 2 the rinse lines 12 are provided in the narrow flow channels 6 and also have an external diameter that is substantially the same as the smaller channel width 7 of these flow channels 6. In this way the rinse lines 12, which abut against the adjacent tubes 3, serve at the same time as spacers 12 for in each case two adjacent tube layers 5. The rinse lines 12 have openings, not illustrated in more detail, over their length, from which a rinse medium, such as for example water, can flow as necessary. With the rinse medium adhering interfering components in the form of solids particles for example can be removed, these being discharged from the register 2 together with the rinse medium, for the most part in the direction of gravity, whereby long service lives can be achieved.

(22) As a comparison of FIGS. 2 and 4 shows, the channel width 7, 7 of the respective flow channel 6, 6 does not vary as regards its height in the illustrated register 2, but remains constant. This is achieved in particular if the tubes 3 run parallel to one another.

(23) FIG. 5 shows a register 2 schematically in a section perpendicular to the longitudinal length of the tubes 3. In this register the tube layers 5 are not parallel, but are aligned slanted to the inflow direction AS of the utility fluid in relation to the register 2. This is achieved by a slight misalignment of the tube rows 4 following one another in the inflow direction AS by a fraction in any case of the channel width of the flow channel 6 of large channel width. In this way flow channels 6 are formed, in which the inlet-side openings 14 of the flow channels 6 for the utility fluid no longer overlap with the outlet-side openings 15 of the flow channels 6.

(24) The register 22 of a heat exchanger 21 illustrated in FIG. 6 differs from the register 2 illustrated in FIGS. 2 and 3 in that tubes 3, 23 of different diameters are installed. In this connection exclusively tubes 3, 23 of identical diameter are provided in each tube layer 5, 25. The tube layers 5, 25 are also assembled together to form the register 22 in such a way that two tube layers 5 with tubes 3 of small diameter are always followed by a tube layer 25 of a large diameter and this in turn is always followed by two tube layers 5 with tubes 3 of small diameter. The two adjacent tube layers 5 with tubes 3 of smaller diameter are in this case held by a common retaining element 8, which extends along the flow channel 6 formed by these two tube layers 5 and is likewise rod-shaped. This flow channel 6 is in each case a flow channel with a constant small channel width 7. On the other hand between the tube layer 25 with the tubes 23 with a large diameter and the adjoining tube layer 5 with tubes 3 with a small diameter, there is always a flow channel 26 that has a large channel width 27.

(25) For economic reasons each tube layer 25 with tubes 23 with a large diameter is held by a separate retaining element 28, which is arranged to the side of the tube layer 25. This retaining element 28 can therefore also function without separate spacers. The two in each case adjacent tube layers 5 with tubes 3 of a smaller diameter are in the illustrated embodiment constructed as already described with reference to FIGS. 2 to 4. The same also applies in principle to the arrangement of the rinse line in the flow channels 6 with a small channel width 7, in other words the flow channels 6 between the tube layers 5 with tubes 3 of a small diameter. The register 22 illustrated in FIG. 6 comprises exclusively rectilinearly formed tubes 3, 23. However in any case tubes that are to some extent curved could also be used to construct the register.

(26) In the register 42 of a heat exchanger 41 illustrated in FIG. 7, similar to the register 2 illustrated in FIG. 2, simply the front-most tube row 44 is illustrated since the further tube rows 44 are arranged flush with the front tube row 44.

(27) The special feature of the register 42 illustrated in FIG. 7 compared to the register 2 according to FIGS. 2 to 4 is that the tubes 43 are alternately part of a first tube layer 45 and a second tube layer 45 of the common tube row 44. The tubes cross one another at the transition from the first tube layer 45 to the second tube layer 45, and vice versa. A flow channel 46 with narrow sections 54, i.e. smaller channel widths 47, is formed between the corresponding crossing points 53. Individual members of the narrow sections 54 have a spacer 50 or a flush line 52. In the illustrated embodiment the flush line 52 has the same external diameter as the spacer 50, so that the flush line 52 holds the two paired crossed tubes 43 simultaneously at the desired interspacing from one another.

(28) The illustrated tubes 43 crossed with one another are rigidly designed, so that means does not have to be provided in each case between two crossover points 53 of the tubes 43 that contributes to the interspacing of the tubes 43. When using flexible tubes such means would preferably be provided between in each case two adjacent crossing points of a flow channel so that the tubes can permanently adopt the desired positions.

(29) The flow channels 46 adjoining the two paired crossed tubes 43 have varying channel widths 47. The flow channels 46 are broadest at the height of the crossing points 53 and narrowest at the mid-height between the crossing points 53. In this way the flow channels 46 adjoining the crossed tubes 43, which channels are bounded by the adjacent rectilinearly running tubes 43 of the tube row 44, in turn have narrow sections 54 and wide sections 55 alternating over their height.

(30) The crossing of the tubes 43 is accomplished in the embodiment illustrated in FIG. 7 in the manner of a wickerwork, in which each of the two tubes 43 crossed with one another is led alternately in the flow direction S in front of and behind the respective other tube 43 to the in each case other tube layer 45, 45.

(31) However, as in the embodiment of a register 62 of a heat exchanger 61 illustrated in FIG. 8, this arrangement can if necessary be dispensed with. Instead, the one tube 63 of the two tubes 63, 63 crossed with one another is always led in front of the other tube 63 to the other tube layer 65, 65.

(32) With the registers 42, 62 illustrated in FIGS. 7 and 8 tubes 43, 63, 63 crossed paired with one another and rectilinearly running tubes 43, 63 in a tube row 44, 64, alternate with one another.

(33) However, with the register 82 of a heat exchanger 81 illustrated in FIG. 9, all tubes 83 of a tube row 84 are in each crossed paired with one another, and more specifically in each case multiply over the longitudinal length of the tubes 83. In this case always the same tubes 83 are crossed with one another. In principle however tubes alternating with different tubes, preferably of different tube layers, could also be crossed with one another. Likewise, it is not essential that simply tubes 83 of adjacent tube layers 85 are crossed with one another and/or that the tubes 83 crossed one another always belong to the same tube row 84. The tubes 83 are crossed with one another in a wickerwork arrangement.

(34) The register 82 illustrated in FIG. 9 has exclusively paired crossed tubes 83. The crossing points 93 of the in each case paired crossed tubes 83 in any case of one tube row 84 lie in common planes 96 parallel to the flow direction. In this way wide sections 95 and narrow sections 94 therebetween are provided in the flow channels 86 between the paired crossed tubes 83 in the region of the crossing points 93, so that the channel widths 87, 87 vary over the longitudinal length of the flow channels 86. The paired crossed tubes 83 define between them in each case a flow channel 86, which has exclusively narrow sections 94 with smaller channel widths 87, though these do not have to be identical to the narrow sections 94 of the in each case adjacent flow channels 86.

(35) With regard to the spacers 90 and rinse lines 92 provided if necessary in the flow channels 86 defined by the paired crossed tubes 83, the same is true as has already been said concerning the heat exchanger 41 illustrated in FIG. 7.

(36) In a non-illustrated embodiment of a register with in each case paired crossed tubes, the crossing points of adjacent tubes in each case crossed with one another could also lie on different planes. For example, only every second crossing point in the direction of a tube row lies in one of these planes. Preferably in each case the crossing points of two tubes crossed with one another looking in the longitudinal direction of the tubes and/or of the register lies substantially, in particular centrally, between the crossing points of the adjacent tubes crossed with one another, in particular on both sides of the tube row. The crossing points of these adjacent in each case paired crossed tubes on both sides of the tube row then preferably lie on common planes, in particular also with the crossing points of the in each case next but one paired crossed tubes of the at least one tube row.

(37) A corresponding arrangement has the result that the flow channel between in each case two paired crossed tubes has a relatively uniform channel width over the flow channel height. According to a corresponding embodiment the corresponding flow channel would assume a substantially sinuous shape.

(38) The floor region of heat exchanger 101 with U-shaped tubes 103 is illustrated in FIG. 10. The U-shaped tubes 103 of the register 102 are suspended in the heat exchanger 101 in the direction of gravity, so that the tube curvatures 117 of the U-shaped tubes 103 point in the direction of the floor 118 of the heat exchanger 101. A gap 119, through which the utility fluid can flow, remains between the bent tubes 103 and the floor 118 of the heat exchanger 101. In the region of the tube curvatures 117 there is installed in the flow direction S of the utility fluid in front of the tubes 103 of the register 102 an in this case plate-shaped barrier 120, which in the illustrated embodiment extends in a plane perpendicular to the flow direction S of the utility fluid. In this connection the barrier 120 is arranged so that a gap 119 is formed between the floor 118 of the heat exchanger 101 and the lower edge 121 of the barrier 120, through which the utility fluid flows with increased velocity and in the floor region entrains deposited interfering components, such as for example particles, without at the same time causing an increased abrasion of the register 102 in the region of the tube curvatures 117. This increased flow velocity of the utility fluid in the gas 122 underneath the tube curvatures 117 is illustrated diagrammatically in the sectional view of FIG. 11.

(39) As a result of the build-up of the utility fluid in the flow direction S in front of the barrier 120, increased flow velocities are likewise produced when the utility fluid overflows the barrier 120, so that the utility fluid flows with increased flow velocity through the region of the tube curvatures 117 and there removes interfering components that have sunk down from above from the flow of the utility fluid. In addition the flow channels with large channel widths can be widened in the region of the lower end of the register, where the tube curvatures are located, as a result of which the flow channels with small channel widths become locally narrower. This can have a positive effect in transporting the interfering components away from the register.