DE102010030780A1 - Heat transfer element for a heat exchanger, method for producing a heat transfer element for a heat exchanger, heat exchangers and Nachrüstverfahren for a heat exchanger - Google Patents

Abstract

The present invention relates to a heat transfer element (10, 20) for a heat exchanger (100, 200), a method for producing a heat transfer element (10, 20) for a heat exchanger (100, 200), a heat exchanger (100, 200) as such and a method for retrofitting an existing heat exchanger, in which the provision of a coating (30) prevents or at least reduces the occurrence of contamination caused by abrasion in one or more heat transfer media (M1, M2) and / or corrosion.

Description

FIELD OF THE INVENTION

The present invention relates to a heat transfer element for a heat exchanger, a method for producing a heat transfer element for a heat exchanger, a heat exchanger itself, namely using the heat transfer element according to the invention, and a retrofitting method for a heat exchanger. In particular, the present invention also relates to CVD-coated and impregnated graphite, which is used in particular for a heat transfer element or heat exchanger element, in particular in a core for a block heat exchanger.

BACKGROUND OF THE INVENTION

In many areas of chemical and / or physical process engineering must be transferred between at least two fluid media - be it liquids, gases, gels, pasty media or the like - quantities of heat to z. B. to cool or heat a designated process medium. In this case, heat exchangers or heat exchangers are used, which have at least one heat transfer element or heat exchanger element, which in turn of the actual process medium to be heated or cooled, and at least one other medium which provides or dissipates the amount of heat and which is often referred to as a service medium is applied to corresponding contact surfaces or contact areas, wherein amount of heat is introduced into one of the contact areas or in one of the contact surfaces, transmitted via a heat conduction mechanism of the heat transfer element to another contact surface or another contact area and then discharged from this to the other medium.

Frequently heat transfer elements are used, which consist essentially of a graphite material which is impregnated at the passing with a respective medium in contact surface with a resin material, for. B. restrict penetration of the respective medium in the porous complex of the heat transfer element underlying material or even prevent.

It often happens that when flowing through the respective medium, in particular by the process medium, particles of the resin impregnation and / or the material underlying the heat transfer element, for. As the graphite material, physically and / or chemically detached, remain in the actual process medium and thereby contaminate it. Often this can not be done.

Also, corrosion on the material of the heat transfer member and / or peeling off corroded material and contaminating the heat transfer fluid (s) with corroded material of the heat transfer member can often not be tolerated.

SUMMARY OF THE INVENTION

The invention is based on the object to provide a heat transfer element for a heat exchanger, a manufacturing method for a heat transfer element for a heat exchanger, a heat exchanger itself and a retrofit method for a heat exchanger, in which in a particularly simple yet reliable manner contamination of the or Heat transfer media can be reduced or even prevented by material of the underlying heat transfer element and corrosion of the material or of the heat transfer elements and contamination of the or the heat transfer fluids with corroded material.

The object underlying the invention is a heat transfer element according to the invention with the features of claim 1, in a method for producing a heat transfer element according to the invention with the features of claim 11, in a heat exchanger according to the invention with the features of claim 21 and in a method for retrofitting a Heat exchanger solved according to the invention with the features of claim 22. Advantageous developments are defined in the subclaims.

According to a first aspect of the present invention, a novel heat transfer element for a heat exchanger is provided, which for flow-separated heat transfer between a first heat transfer medium as a process medium and a second heat transfer medium as a service medium, a first contact area and a second contact area for fluidly separated contact with the first heat transfer medium or with the second heat transfer medium formed substantially with or from one or more materials from the group of materials comprising graphite materials, graphites and open cell and non-sintered SiC or silicon carbide materials, and wherein at least one of the first and second contact regions is partially or coated completely with one or more materials from the group of materials coated, the SiC or Silicon carbide materials, carbide oxide materials, silicide materials, tungsten titanate materials and their derivatives, and combinations. Here are as the first and second heat transfer fluids fluids possible, ie z. As liquids, gases, gelatinous or pasty media, foams, slurries and their combinations and mixtures.

It is thus a core idea of the present invention to reduce or avoid the likelihood of detachment and / or corrosion of material underlying the heat transfer element by providing at least one of the first and second contact areas or contact surfaces of the heat transfer element with the heat transfer element underlying material is formed with a particularly resistant or abrasion resistant coating, even if the material underlying the heat transfer element is formed of a graphite material or an open-pored and / or non-sintered SiC or Siliziumcarbidmaterial.

An impregnation with an impregnating material may be formed with or from one or more materials from the group comprising resin materials, phenolic resin materials and their derivatives, and combinations. The impregnation with the impregnating material serves in particular to avoid too deep penetration and in particular penetration of the material lying on the heat transfer element with one of the heat transfer media whose remaining material is thereby mixed, even if only in the long term, with each other and / or to reduce or prevent contamination in a media change.

The impregnation with the impregnating material may be wholly or partly formed on and / or in the coating and / or completely or partially on and / or in the first contact region and the second contact region. Since the coating to avoid contamination, z. B. by abrasion or the like the heat transfer element underlying material anyway at least partially, if not completely, seals, so there closes pores, it is particularly advantageous if an impregnation to be provided is formed on or in the coating to avoid contamination or is , This also offers procedural advantages, because in the processing of the coating on the material underlying the heat transfer element on thermal boundary conditions of the material of the impregnation must be taken into account. So z. B. in the production of high-temperature steps are driven without damage or decomposition of the impregnating is to be expected, since this can then be in retrospect, so after the high-temperature step or introduced.

For the coating with the coating material different structures and methods for their production are conceivable.

The coating may be formed as a CVD coating.

Alternatively or additionally, the coating can be formed as a chemical and / or physical conversion region-in particular via a process of wholly or partly chemical and / or physical conversion of the material of the first and / or second contact region.

The coating may also be alternatively or additionally formed via a process of plasma spraying and / or flame spraying. In addition, the formation of a solid layer on the so-called liquid siliciding, both in the dipping process as well as in the evaporation process and in the wicking process, has already been successfully tested.

Depending on the nature of the material intended for the coating or the materials intended for the coating, different coating mechanisms and corresponding production methods may be used, but the formation of the coating as a chemical and / or physical conversion layer is particularly elegant, in particular if none or only minor additional material components must be provided for coating in their amount.

Various manufacturing methods and structures may or may not be combined in building the coating.

The heat transfer element according to the invention may be formed as a heat exchanger plate or heat exchanger plate of a plate heat exchanger or plate heat exchanger.

The heat transfer element according to the invention can also be designed as a heat transfer core or block or as a heat exchanger core or block of a block heat exchanger or block heat exchanger.

Furthermore, the heat transfer element according to the invention can be designed as a heat exchanger tube or heat exchanger tube of a tube heat exchanger or tube heat exchanger.

The inventive concept can therefore be used in principle in all heat exchangers or heat exchangers, in which one or more heat transfer elements or heat exchanger elements are used, which follow the above-described principle, namely at least one contact area or at a contact surface of a medium for heat transfer, in particular To be flowed to a process medium and thus come into mechanical contact with this, which due to physical and / or chemical interaction abrasion on a surface of the contact region or the contact surface of the heat transfer element is conceivable.

According to another aspect of the present invention, there is provided a method of manufacturing a heat transfer element for a heat exchanger, wherein the heat transfer element for flow separated heat transfer between a first heat transfer medium as the process medium and a second heat transfer medium as a service medium with a first contact area and with a second contact area to the flow formed with the first heat transfer medium or with the second heat transfer medium, wherein the heat transfer element is formed substantially with or from one or more materials from the group of materials comprising graphite materials, graphites and open-cell and non-sintered SiC or Siliziumcarbidmaterialien , and wherein at least one of the first and second contact areas is wholly or partially covered by one or more materials alien from the group of materials is coated as a coating, the SiC or silicon carbide materials, pyrocarbon, oxide ceramics such. Chromium oxides, diamond, carbide oxide materials, silicide materials, tungsten titanate materials and their derivatives and combinations.

An impregnation with an impregnating material may be formed with or from one or more of the group consisting of resin materials, phenolic resin materials and their derivatives and combinations.

The impregnation with the impregnating material may be wholly or partly formed on and / or in the coating and / or completely or partially on and / or in the first contact region and the second contact region.

The coating can be formed as a CVD coating.

The coating can also be formed as a CVI coating.

Alternatively or additionally, the coating may be formed as a chemical and / or physical conversion region, in particular via a process of wholly or partially chemically and / or physically converting the material of the first and / or second contact region.

The coating may also be additionally or alternatively formed via a process of plasma spraying and / or flame spraying.

The heat transfer member may be formed as a heat transfer plate or heat exchanger plate of a plate heat exchanger or plate heat exchanger.

The heat transfer element can also be designed as a heat transfer core or block or as a heat exchanger core or block of a block heat exchanger or block heat exchanger.

Also, the heat transfer element according to the invention can be formed as a heat exchanger tube or heat exchanger tube of a Rohrwärmeübertragers or tube heat exchanger.

According to a further aspect of the present invention, a heat exchanger is provided in which one or more heat transfer elements according to the invention are or are formed. In addition, according to a further aspect of the present invention, a method for retrofitting an existing heat exchanger is specified, in which one or more existing and in particular conventional heat transfer elements are replaced by one or more corresponding heat transfer elements according to the invention and / or in which one or more existing and In particular, conventional heat transfer elements are converted to heat transfer elements according to the invention, in particular according to the inventive method is used.

These and other aspects will be explained by way of example on the basis of the accompanying schematic drawings.

BRIEF DESCRIPTION OF THE FIGURES

1 is a schematic and exploded perspective view of an embodiment of a heat exchanger according to the invention in the manner of a plate heat exchanger using an embodiment of the heat transfer element according to the invention in the manner of a heat exchanger plate.

2 shows in a schematic and perspective side view of a single heat transfer element of the arrangement 1 ,

3A , B show in schematic and sectional side view two intermediate states which are achieved in the embodiment of a production method according to the invention for a heat transfer element according to the invention.

4 is a schematic and perspective side view of another embodiment of a heat exchanger according to the invention, in the manner of a block heat exchanger.

5A , B show in schematic and sectional side view two intermediate states, which are achieved in another embodiment of a production method according to the invention for a heat transfer element according to the invention.

6A , B show in schematic and sectional side view two intermediate states, which are achieved in another embodiment of a production method according to the invention for a heat transfer element according to the invention.

7A , B show in schematic and sectional top view two intermediate states, which are achieved in a further embodiment of a production method according to the invention for a heat transfer element according to the invention.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Hereinafter, embodiments of the present invention will be described. All embodiments of the invention and also their technical features and properties can be isolated individually or combined randomly combined with each other arbitrarily and without restriction.

Structurally and / or functionally identical, similar or identically acting features or elements are referred to below in connection with the figures with the same reference numerals. Not always will a detailed description of these features or elements be repeated.

First of all, reference is made to the drawings in general.

The present invention relates to a heat transfer element 10 . 20 for a heat exchanger 100 . 200 , a method for producing a heat transfer element 10 . 20 for a heat exchanger 100 . 200 , a heat exchanger 100 . 200 as such, as well as a method for retrofitting an existing heat exchanger, in which by providing a coating 30 the occurrence by abrasion and / or corrosion of generated impurities in one or more heat transfer media M1, M2 and / or corrosion are prevented or at least reduced or become.

In addition to the general principle described above, the present invention also relates to CVD-coated and impregnated graphite and in particular to its use for the design of heat transfer or heat exchanger elements 10 . 20 ,

Especially in the fine chemicals and pharmaceutical industries are heat exchangers 100 . 200 and heat exchangers 100 . 200 Often resin impregnated graphite, used to cool or heat media M1, M2. It happens that graphite particles or particles originating from the impregnation, ie resin particles, through which the heat exchanger 100 . 200 , in particular in the form of a block heat exchanger 200 , flowing process medium M1 from the surfaces 22v or from the walls 22v the product holes 22 detached and / or corroded. These particles are to be regarded as foreign particles because they contaminate the end product, so that in the worst case the entire production batch must be discarded.

To avoid or avoid this problem, z. B. be thought of, heat exchangers 100 . 200 to use their heat transfer elements 10 . 20 or heat exchanger elements 10 . 20 completely made of silicon carbide or SiC. Compared with graphite heat exchanger elements or heat transfer elements silicon carbide has the advantage that a significantly higher abrasion and / or corrosion resistance is present and thus virtually no silicon carbide particles in the heat transfer medium M1, M2, in particular in the product medium M1 or in the product solution M1 occur.

A disadvantage of a completely made of silicon carbide heat transfer element or heat exchanger element are compared to pure graphite many times higher material and manufacturing costs, so that in general this option can be used only in exceptional cases. In addition, the extremely brittle behavior of SiC ceramics is often disadvantageous due to the application.

The present invention also makes use of the finding that, in particular, graphite surfaces can be coated with silicon carbide or SiC via a CVD method, which is carried out in particular at temperatures of more than 1000 ° C., in order to reduce the abrasion and / or corrosion resistance of a heat transfer element 10 . 20 underlying material 10 ' . 20 ' , ie in particular of the underlying graphite material. This also applies to Substarte such. B. CSiC material. Here, the reduced corrosion resistance of free carbon is problematic and contrary to a use of above.

It is advantageous that on the one hand by using z. B. of silicon carbide as a coating material 30 ' On the other hand, however, the manufacturing cost does not increase excessively since the underlying material 10 ' . 20 ' may still be a cost-effective material, in particular a graphite material, which then on its surface by the coating 30 quasi refined.

Especially with so-called block heat exchangers 200 could also be thought of, the heat exchanger block 20 , especially with regard to the product bores 22 to connect a block element, which consists entirely of an abrasion-resistant material, for. As silicon carbide, and which but no service holes 24 for the second heat transfer medium M2. In this way, it is ensured that the first contact with the process medium M1 is taken over by an abrasion-resistant component.

Although this makes it possible to lower impurities to their extent, the provision of a bloc which is completely made of abrasion-resistant material is likewise expensive and has the technical disadvantage that a dead volume is introduced before the actual heat exchanger process, thus reducing the overall effectiveness of such a plant.

In contrast, the invention proposes a more refined procedure, namely the coating of one or more heat transfer elements 10 . 20 a heat exchanger 100 . 200 with an abrasion and / or corrosion resistant material 30 ' , at least in the areas or subregions where contact with the process medium M1 occurs.

The invention thus provides a cost-effective and possibly a mechanical, compared to brittle fracture, more tolerant variant to heat exchanger elements 10 . 20 , z. B. to block heat exchangers, which are made entirely of an abrasion and / or corrosion-resistant material. It can thus be a cost-effective and conventional material 10 ' . 20 ' for the heat transfer elements 10 . 20 be used, in which then all surfaces that come into contact with the abrasive and / or corrosive medium M1, M2, z. B. the two end surfaces 20e and the product holes 22 in a block heat exchanger 200 , with a layer 30 made of an abrasion and / or corrosion resistant material 30 ' , z. As silicon carbide, are protected and its pores then completely with a synthetic resin 40 ' are impregnated to the tightness of the heat transfer element 10 . 20 , in particular the heat exchanger block 20 to ensure.

One on synthetic resin 40 ' based impregnation 40 or otherwise impregnation 40 is often necessary because it can often not be ensured that any surface of the heat transfer element coming into contact with the process medium M1 10 . 20 , in particular the block heat exchanger 200 , completely by the used abrasion and / or corrosion resistant material 30 ' , in particular by the silicon carbide, is sealed.

An impregnation 40 , in particular with synthetic resin 40 ' , must be done after the process of coating with the abrasions- and / or corrosion-resistant material, since temperatures of more than 1000 ° C during the coating process, the material 40 ' for impregnation 40 can destroy.

An embodiment of a manufacturing method for a heat transfer element according to the invention 10 . 20 , in particular for a heat exchanger block 200 or the like, may have the following structure:
A finished block 20 , z. B. graphite 20 ' or the like, is coated with a silicon carbide coating 30 coated on the basis of a CVD method, wherein z. B. the lateral surfaces 20m of the block z. B. can be covered with a graphite foil, so there is no coating.

Alternatively, the service holes 24 after coating with the silicon carbide material 30 ' in the block 20 be introduced.

Subsequently, the with silicon carbide 30 ' coated block 20 analogous to the production of conventional heat exchanger blocks with an impregnation 40 trained, z. B. with a synthetic resin 40 ' impregnated. Before impregnation 40 can the two end faces 20e of the block 20 covered with two correspondingly large metal discs, with a seal between each Blockendfläche 20e and the metal disc the contact of the impregnating 40 ' with the block end faces 20e and the product holes 22 prevented. The resin 40 ' for impregnation 40 can over the lateral surfaces 20m and the service holes 24 in the block 20 penetration. The jacket disks are z. B. by several tie rods passing through the product holes 22 be guided, fixed and braced. After impregnation 40 becomes the block 20 placed in the hardening furnace with the strained metal plates. The synthetic resin 40 ' is cured according to a standard procedure. The end product obtained on the product side with silicon carbide coated and in the product wells 22 resin-free block 20 ,

Such and similar inventive production process and heat transfer elements according to the invention 10 . 20 have many advantages over known approaches:
The heat exchanger produced in the manner according to the invention 100 . 200 or heat exchanger 100 . 200 , in particular, block heat exchangers 200 , is resistant to abrasive and / or corrosive media and contributes - like a conventional heat exchanger - to the heat exchange between a process medium M1 and a service medium M2 completely, ie without dead volumes occur.

Furthermore, the abrasion-resistant layer prevents 30 or coating 30 , in particular the SiC layer both the adsorption of media M1, M2 and their subsequent desorption in a product change or when changing the service medium M2. In addition, the abrasion and / or corrosion-resistant layer 30 or the SiC layer 30 Prevent any abrasion or attack of graphite particles or resin particles in the process medium M1 and thus in the product solution and / or corrosion.

Advantageously, substrate material 10 ' . 20 ' - So z. B. the graphite 10 ' . 20 ' And coating material 30 ' be matched in terms of their thermal expansion coefficients.

Namely, according to another aspect of the present invention, the ratio of the thermal expansion coefficients of the substrate material 10 ' . 20 ' , in particular of the graphite substrate 10 ' . 20 ' , and the coating material 30 ' and / or impregnating material 40 ' - In particular, the CVD SiC - z. B. can be selected and adjusted so that - especially at the highest process temperature - values in the range between about 1.2 to about 0.8, preferably in the range between about 1.1 and about 0.9 and more preferably in the range between about 1.05 to 0.95. Ideally, the thermal expansion coefficients of the material pairings are identical.

Surprisingly, it has been found that layer thicknesses of less than 5 microns are already resistant to abrasion and corrosion. Particles are successfully retained, corrosion of the substrate is prevented, the surface hardness is extremely increased. Ideally, therefore, layer thicknesses of between 5 and 1000 μm are applied, preferably between 20 and 400 μm, and more preferably between 50 and 200 μm.

Preferred process temperatures are in particular in the range between about 1200 ° C and about 2400 ° C, depending on the applied coating method, in particular CVD method.

Surprisingly, can be achieved absolutely crack-free coatings by such skillfully selected material pairings with respect to their thermal expansion, so that, if necessary, completely on a seal z. B. can be dispensed with by resins.

Such surfaces produced in addition to a high wear resistance on a high corrosion resistance, which is equivalent in particular to that of a SiC, alpha-SiC or α-SiC.

Now, reference will be made in detail to the drawings.

1 shows a schematic and perspective exploded view of an embodiment of a heat exchanger according to the invention 100 in the form of a so-called plate heat exchanger 100 ' or plate heat exchanger 100 which is made of an arrangement 110 like a stack of a plurality of heat transfer plates 10 or heat exchanger plates 10 formed inventive heat transfer elements 10 or heat exchanger elements 10 ,

The arrows indicate the inflows and outflows of the first and second heat transfer media M1 and M2, which flow alternately in the spaces R1, ..., Rn as flow spaces, with corresponding sealing means between the successive heat transfer elements 10 are provided (not explicitly shown here) to prevent mixing of the first and second heat transfer media M1 and M2 together.

2 shows a schematic and perspective side view of a single heat transfer element 10 in the form of a heat transfer plate 10 from the arrangement of 1 , This heat transfer element 10 in sheet form consists essentially of a base material 10 ' , z. B. of a graphite material, and has an upper side 100 or front side 100 and a back 10u or bottom 10u on. The front 100 and the back 10u can with appropriate flow channels in the surface of the underlying material 10 ' the plate 10 be formed to the mechanical contact and thus the heat transfer between the two sides 100 and 10u the plate 10 to intensify. These flow or flow channels are not explicitly shown here and form a kind of relief on the top 100 or bottom 10u the plate 10 ,

The 3A and 3B show different stages of production for the in 2 shown heat transfer element 10 in plate form.

In the 3A is practically the blank for the heat transfer element 10 indicated in plate form. That means the plate 10 essentially from a z. B. conventional material 10 ' , z. B. of a graphite material, as a disk substrate 10 ' consists. Also indicated are the top 100 and the bottom 10u the plate 10 ,

In the transition to the representation of the 3B will be at least on top 100 and the bottom 10u a coating 30 made of an abrasion-resistant material 30 ' educated.

Often it is sufficient that one side - so either the top 100 or her bottom 10u - with the abrasion-resistant material 30 ' as a coating 30 is formed, which with the actual process medium, eg. B. the heat transfer medium M1, in contact, which must not be contaminated as a product. Whether the service medium, ie z. As the second heat transfer medium M2 is contaminated or not, is often secondary. Therefore, the page - in the 3A and 3B the bottom 10u - often only optional with the coating 30 this is in the 3B indicated by dashed lines.

The 4 shows a schematic and perspective side view of another embodiment of a heat exchanger according to the invention 200 or heat exchanger 200 , namely in the form of a block heat exchanger 200 ' with a circular cylindrical heat exchanger core or heat exchanger core 20 from a material 20 ' , which parallel to the axis of symmetry, ie in the Z direction first, vertical or vertical holes 22 or process drilling 22 for the first heat transfer medium M1 or process medium M1 and perpendicular to this second or horizontal holes 24 or service holes 24 for the second heat transfer medium M2 or service medium M2.

The holes 22 and 24 do not communicate with each other so that mixing of the first and second heat transfer media M1 and M2 can not take place. For lateral and vertical limitation and control of the flows of the first and second heat transfer media M1 and M2 is a Leitscheibenrahmen 50 . 60 with an arrangement of several guide disks 50 which are in corresponding strips 60 clamped provided. Shown are still the lateral surface 20m and the end surfaces 20e the block formed as a heat transfer element 20 as well as the areas 20v . 20h or inner surfaces 20v . 20h the vertical or horizontal channels or holes 22 respectively. 24 ,

According to the present invention may be in a block-shaped heat transfer element 20 according to 4 on the one hand the end surfaces 20e , the lateral surface 20m , but also the inner surfaces 20v and 20h the first and second holes 22 respectively. 24 for the process medium M1 or the service medium M2 with a corresponding coating 30 with an abrasion-resistant coating material 30 ' be educated.

This is in the 5A to 7B shown again in the context of two consecutive process steps in a schematic and sectional side view or in a schematic plan view.

The 5A and 5B show a section of the arrangement 4 for a block-shaped heat transfer element 20 , where only the vertical holes 22 are shown parallel to the Z-direction, the z. B. the transport of the process medium M1 or first heat transfer medium M1 serve and inner surfaces 20v exhibit.

The basic material 20 ' this heat transfer element 20 can be a conventional material 20 ' be. In the transition to the in 5B shown intermediate state then become the end surfaces 20e the block formed as a heat transfer element 20 and the inner surfaces 20v or inside pages 20v the vertical holes 22 or vertical flow channels 22 with a coating 30 with or from the coating material 30 ' educated. If necessary, this also results at the end face 20e a corresponding coating 30 ,

If necessary, the cross section of the vertical holes 22 slightly restricted, but the illustration in the 5A to 7B not to scale; the actual reduction in the clear width of the holes 22 and 24 with the inner surfaces 20v and 20h is limited only slightly.

The same applies to a coating that covers the lateral surface 20m and the inner surfaces 20h or inside pages 20h horizontal bores 24 concern, as stated in the 6A and 6B analogous to the 5A and 5B is shown.

The 7A and 7B a plan view of the arrangement of the block heat exchanger 200 ' of the 4 to 6B against the Z-direction, ie directly on the upper end surface 20e of the underlying cylinder.

Even with tubular heat exchangers, which are not shown here graphically, such a coating 30 conceivable on the inside and / or on the outside of a respective heat exchanger tube.

LIST OF REFERENCE NUMBERS

10

Heat transfer element, heat exchanger element, heat transfer plate, heat exchanger plate

10 '

Material of the heat transfer element

10o

Top, front

10u

Bottom, back

20

Heat transfer element, heat exchanger element, heat transfer core, heat exchanger core

20 '

Material of the heat transfer element

20e

end face

20h

Surface of horizontal or service hole 24

20m

lateral surface

20v

Surface or inside of the vertical or process bore 22

22

vertical drilling, process drilling, drilling for the first heat transfer or process medium

24

horizontal hole, service hole, hole for the second heat transfer medium or service medium

30

coating

30 '

coating material

40

impregnation

40 '

waterproofing

50

Guide disc for block heat exchanger 200 '

60

Rail / frame for the Leitscheibe 50 for block heat exchangers 200 '

100

Heat exchanger, heat exchanger,

100 '

Plate heat exchanger, plate heat exchanger

110

Arrangement / stack of a plurality of heat exchanger elements / heat exchanger plates 10

200

Heat exchanger, heat exchanger

200 '

Block heat exchanger, block heat exchanger

M1

first heat transfer medium, process medium, product medium

M2

second heat transfer medium, service medium

rj

Space, flow space, j = 1, ..., n

Claims (22)

Heat transfer element ( 10 . 20 ) for a heat exchanger ( 100 . 200 ), which for flow-separated heat transfer between a first heat transfer medium (M1) as a process medium (M1) and a second heat transfer medium (M2) as a service medium (M2) a first contact area ( 100 ; 20e . 20v ) and a second contact area ( 10u ; 20h . 20m ) for flow-separated contact with the first heat transfer medium (M1) or with the second heat transfer medium (M2), which essentially comprises or consists of one or more materials ( 10 ' . 20 ' ) is formed from the group of materials comprising graphite materials, graphites, and open-cell and non-sintered SiC or silicon carbide materials, and in which at least one of the first and second contact regions ( 100 ; 20e . 20v . 20u . 20h . 20m ) partially or completely with one or more materials from the group of materials ( 30 ' ) as a coating ( 30 ) having SiC or silicon carbide materials, carbide oxide materials, silicide materials, tungsten titanate materials, oxide materials, pyrocarbon, diamond, and their derivatives and combinations. Heat transfer element ( 10 . 20 ) according to claim 1, wherein an impregnation ( 40 ) with an impregnating material ( 40 ' ) is formed with or from one or more materials from the group comprising resin materials, phenolic resin materials and their derivatives and combinations. Heat transfer element ( 10 . 20 ) according to claim 2, in which the impregnation ( 40 ) with the impregnating material ( 40 ' ) wholly or partly on and / or in the coating ( 30 ) and / or in whole or in part on and / or in the first contact area ( 100 ; 20e . 20v ) and the second contact area ( 10u ; 20h . 20m ) is trained. Heat transfer element ( 10 . 20 ) according to one of the preceding claims, in which the coating ( 30 ) is designed as a CVD coating. Heat transfer element ( 10 . 20 ) according to one of the preceding claims, in which the coating ( 30 ) as a chemical and / or physical transformation area - in particular via a process of wholly or partly chemical and / or physically converting the material ( 10 ' . 20 ' ) of the first and / or second contact area ( 100 . 10u ; 20v . 20h . 20m ) - is trained. Heat transfer element ( 10 . 20 ) according to one of the preceding claims, in which the coating ( 30 ) is formed via a process of plasma spraying and / or flame spraying. Heat transfer element ( 10 . 20 ) according to one of the preceding claims, which serves as a heat transfer plate ( 10 ) or heat exchanger plate ( 10 ) of a plate heat exchanger ( 100 ) or plate heat exchanger ( 100 ) is trained. Heat transfer element ( 10 . 20 ) according to one of the preceding claims 1 to 6, which serves as a heat transfer core ( 20 ) or heat exchanger core ( 20 ) of a block heat exchanger ( 200 ) or block heat exchanger ( 200 ) is trained. Heat transfer element ( 10 . 20 ) according to one of the preceding claims 1 to 6, which is designed as a heat exchanger tube or heat exchanger tube of a tube heat exchanger or tube heat exchanger. Heat transfer element ( 10 . 20 ) according to one of the preceding claims, in which the material ( 10 ' . 20 ' ) of the heat transfer element ( 10 . 20 ) and the material ( 30 ' ) of the coating ( 30 ) are chosen so coordinated that the ratio of the thermal expansion coefficients of the material 10 ' . 20 ' ) of the heat transfer element ( 10 . 20 ), in particular a graphite substrate ( 10 ' . 20 ' ), and the material ( 30 ' ) of the coating ( 30 ) - in particular a CVD SiC material ( 30 ' ) - and / or an impregnating material ( 40 ' ) has a value in the range between about 1.2 to about 0.8, preferably in the range between about 1.1 and about 0.9 and more preferably in the range between about 1.05 to about 0.95, in particular in a temperature range from about 1200 ° C to about 2400 ° C or a portion thereof. Method for producing a heat transfer element ( 10 . 20 ) for a heat exchanger ( 100 . 200 ), in which the heat transfer element ( 10 . 20 ) for flow-separated heat transfer between a first heat transfer medium (M1) as process medium (M1) and a second heat transfer medium (M2) as service medium (M2) with a first contact region ( 100 ; 20e . 20v ) and with a second contact area ( 10u ; 20h . 20m ) is formed for the flow-separated contacting with the first heat transfer medium (M1) or with the second heat transfer medium (M2), in which the heat transfer element ( 10 . 20 ) substantially with or from one or more materials ( 10 ' . 20 ' ) is formed from the group of materials comprising graphite materials, graphites, and open-pore and non-sintered SiC or silicon carbide materials, and wherein at least one of the first and second contact regions (FIG. 100 ; 20e . 20v . 20u . 20h . 20m ) in whole or in part with one or more materials from the group of materials ( 30 ' ) as a coating ( 30 ) having SiC or silicon carbide materials, carbide oxide materials, silicide materials, tungsten titanate materials and their derivatives, and combinations. Process according to claim 11, in which an impregnation ( 40 ) with an impregnating material ( 40 ' ) is formed with or from one or more materials from the group comprising resin materials, phenolic resin materials and their derivatives, and combinations. Method according to one of the preceding claims 11 or 12, wherein the impregnation ( 40 ) with the impregnating material ( 40 ' ) wholly or partly on and / or in the coating ( 30 ) and / or in whole or in part on and / or in the first contact area ( 100 ; 20e . 20v ) and the second contact area ( 10u ; 20h . 20m ) is trained. Method according to one of the preceding claims 11 to 13, wherein the coating ( 30 ) is formed as a CVD coating. Method according to one of the preceding claims 11 to 14, wherein the coating ( 30 ) as a chemical and / or physical transformation region - in particular via a process of the wholly or partially chemical and / or physical transformation of the material ( 10 ' . 20 ' ) of the first and / or second contact area ( 100 . 10u ; 20v . 20h . 20m ) - is formed. Method according to one of the preceding claims 11 to 15, wherein the coating ( 30 ) is formed via a process of plasma spraying and / or flame spraying. Method according to one of the preceding claims 11 to 16, wherein the heat transfer element ( 10 . 20 ) as heat transfer plate ( 10 ) or heat exchanger plate ( 10 ) of a plate heat exchanger ( 100 ) or plate heat exchanger ( 100 ) is formed. Method according to one of the preceding claims 11 to 16, wherein the heat transfer element ( 10 . 20 ) as a heat transfer core ( 20 ) or heat exchanger core ( 20 ) one Block heat exchanger ( 200 ) or block heat exchanger ( 200 ) is formed. Method according to one of the preceding claims 11 to 16, wherein the heat transfer element ( 10 . 20 ) is formed as a heat exchanger tube or heat exchanger tube of a tube heat exchanger or tube heat exchanger. Method according to one of the preceding claims 11 to 19, wherein the material ( 10 ' . 20 ' ) of the heat transfer element ( 10 . 20 ) and the material ( 30 ' ) of the coating ( 30 ) are chosen to be coordinated or that the ratio of the thermal expansion coefficients of the material 10 ' . 20 ' ) of the heat transfer element ( 10 . 20 ), in particular a graphite substrate ( 10 ' . 20 ' ), and the material ( 30 ' ) of the coating ( 30 ) - in particular a CVD SiC material ( 30 ' ) - and / or an impregnating material ( 40 ' ) has a value in the range between about 1.2 to about 0.8, preferably in the range between about 1.1 and about 0.9 and more preferably in the range between about 1.05 to about 0.95, in particular in a temperature range from about 1200 ° C to about 2400 ° C or a portion thereof. Heat exchanger ( 100 . 200 ), in which one or more heat transfer elements ( 10 . 20 ) are formed according to one of claims 1 to 10. Method for retrofitting a heat exchanger ( 100 . 200 ), in which one or more existing heat transfer elements by one or more corresponding heat transfer elements ( 10 . 20 ) according to one of claims 1 to 10 and / or in which one or more existing heat transfer elements to heat transfer elements ( 10 . 20 ) are converted according to one of the preceding claims 1 to 10, in particular according to a method according to any one of the preceding claims 11 to 20.

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