DE2105791A1 - Heat exchanger device - Google Patents

Description

PATENT LAWYERS

DR.-PH1L. G. NICK? L- Da .-! \! G. J. DORNER

8 MONKS 15
LANDWEHRSTR. 35 POST BOX IO4

Tel. (08 11) 555719 üancaen, February 3rd ly '/ l

Attorney Act: 2 / - Pat. 7

Raytheon Company, 141 Storing Street, Lexinrton, ivIa.ü21 / 3, United States of America

, heat exchange equipment

The invention relates to viärmeaustausciiereinricatungen in a very compact design mix burners noiier power and In particular, notices to lower the output side K-ohlenmonoxjiar-j-ehaltes.

For certain purposes, you need very small 'heat exchangers, which in connection with burner honers Power operated, so that there is the possibility of handling large amounts of heat in the smallest of spaces and provide. It is true that burners of high power and intensity can be built with a very high degree of efficiency, so that all Carbon, which is contained in the fuel normally supplied to such burners, is converted into conene dioxide is, but it has been found that when a working at a relatively low temperature If the heat exchanger is placed too close to the burner, the combustion products of the device are uncomfortable or inadmissibly hone with carbon monoxide content. If one tries now to avoid this disadvantage by using the If the heat exchanger is arranged at a greater distance from the burner, it is necessary to forego the small space requirement of the device.

The object of the invention is to be achieved in the case of a heat exchanger device with a burner, higher

109836/0912

Lais tun.-r aan kohienrnonoxyd-J-eiialt der VerDreiuiur ^ srruαακ ua • Grots of the use of a Lai low tempera oar arueiü 'Väruieaustauscners oxme a ver_; röiieran_ · aas _J .ia ..- iribäaai-l'3s to lower icon.

f from a Y / iirnieaustauscriereinrioiiCun ^ : axi a burner which is used to burn coal-stoxic fuels, which is assigned to one of its internal combustion areas and naiie to a Vfärjaeaastauscner angeoran.3c, whose operation is ⁱ xebexsxe "Naturally below the combination temperature of Lo ^ ienmonoxyd and Sa ^ erstot'i xie ^ c, we a the asked Äuf, raoe aaäurch, solved, aai Z7» iscüön de: / i the mentioned combustion area and the heat exchange a V.Irmesendee for withdrawal. from Vv. Irnie energy from the burners for lowering; - from their temperature to the -renarirne Rekotnöinaxion temperature - Colon monoxide, which is present in the chemical products, forms with oxygen or irreversible heat from exchangeable cone dioxide.

Appropriate configuration as just described briefly The rest of the facility is the result of the adjoining Expectations.

In accordance with the invention, a grid or sieve made of heat-resistant material, such as heat-resistant metal, for example, is arranged at a specific point between the burner and the heat exchanger. The location of the (litters or the screen is so chosen that this beyond the point at which _r is initially takes place complete combustion of the fuel. At the same time the distance aber.ist from the surface of the heat exchanger sufficiently gewänlt large to ensure that a complete Recombination of the approximately dissociated carbon dioxide takes place,

- 2 10983G / 0912

COPY 'bad ORIGINAL

de Jim

ue.or ciLu i.aiiien gases reach the '.V'är ^ eaustuellen-surface .. The r.renner is with so j; roüer power and xiiuoxisi UlLI cetriecan, jü :; at eiern point at which zuiiici.si an ι oilstJ.ndi.re Verui-emian, ^ ere ^ oiit, uie iemperaxui the Vsi'braimun ^ 's: ase a ^ e D-Lssoziaxionstemperaxur von Konlendioxyd obers iei..iX . If the ueiiaen 3-ase flow past this point, they come mix the Gi tear or sieve in Beranrting, weicues through the, iasam. ^ Eri Wirkan. ^ .On iiirineieiuan. ·; from the Lt ^ rxrefienaen Ciasen n.er ωχΰνοη der u'oi'axiiun.g uei · xiei.ien Uase Ln dei "'/ erurennuiusione aui feue.z; vvira. The lemoei-a uu.r- des Jiiiers o-jer screen isx so yet, it aa.:i '.vesanclicixe Enarvieir.encG: .. :: ·· dwr btra; l'on-_: sb ^ iex that .on the u: _a; rebenäen La _t xeilen. absorbier-t v; iid, so aa.3 die remizarauui- des Lattice oaei · Sieoes ^ nxei 'uie .. "named i / issuz-.ationste.Ti ^ ei-axai · accaseiiicx di dasjeniren remperaxui ce-

, in which the eiconibination of Konlen-'nonoxyd and oauarstofi takes place. Since teay.eratur of the .'er-cre; Jiun ^ s ci-o uui: ie '.vii-d through the sieve or Gi χ tar as far as einiedii - ;: c, cia ::. also the verbi-ennun _f ;; sprod'ak ze raix their temper-ai.ii m α en r.eiCombinaxiotis-Tem ^ eraxurcsreic ^ aaracjti ^ eüraohx \ v3i aen ^ nu on darr. . ". ege to, ', irnieaas laascüex ¹ in mrer I'e :: iceraxu. nic.ix iuei- die Dissociationste: ;; ceraiur .on Konieuaioxyd ansiei .-« n. Päiit die ler.pei-axar aer .iase a.riai aaf aen ii9-io.:;c::.a ^ ionscereich zaivek, so \ eriJ. ^ 1 "- the üßicosci ^ - tioii of x- o -.- iea.r.onoxyd and Sa. * ersxofi 'with au-fieroraei-xiioiier ■ u-esehvvizid 1. ^ 1.91 u, so there.; · as uio-clic ^ is, the G-itxer or- sieve - "iamlicui -la.oe an aen V (* är: neausxaascüer "m ζ ^ -. erez-ei-, o; ine aa .; aa; i aui a \ ollstlndi ^ e ixekomcinaxion of the named. -rase verzi-c-men.-au.i. D8 ^% r '/. virni3au.s'"ausciier be there remains a ieniperatar who uiix outside the EeKo.iibinat-ons-ie.Txe :: atur- bsreiclies xiegz. Wards one admit that3 a_a" ^ ei λ en the 7th ^: ärineausxausciier reach, v; äl: rend sie noc:

1 0 9 =? ^: ; "·. - 1 2

S BAD ORIGINAL

contained substantial amounts, of carbon monoxide, so would a quenching of the gases and not the desired recombination take place.

In the following, the invention is illustrated by the description of an exemplary embodiment with reference to the attached Drawing explained in more detail in which:

FIG. 1 shows a vertical section through a heat exchanger device according to the invention and

FIG. 2 shows a cross section along the egg in FIG. 1 indicated section line 2-2

represent. The burner 1 shown in the drawing figures belongs to a type of high efficiency and no performance how it was created elsewhere. burner this type 'have a cylindrical sleeve 2 with a Strand multitude of torch openings 3 is used as channels serve, through which the gas to be burned exits. Said gas, which is a mixture of air and a carbon-containing, flammable substance, such as natural gas, gasoline, Lie than, propane or the like, formed can be, is fed to the burner via an inlet line 4. The line 4 is from a suitable fuel gas source iier, as already suggested elsewhere was fed with the gas-air mixture, which is preferably up to 30> ό excess of air with respect to the contains stoichiometric ratio. Burners of the type briefly described here can generate extremely large amounts of heat produce and display, for example, a performance of

ρ over 700 heat units per hour and ge cm burner surface. In the upper operating range, the speed of the gas-air mixture when exiting the burner openings 3 over

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• j

1.6 m per second. In the entire operating range of the burner of this type, the outer limit of the flame jacket of the burner 1 is about 6 mm to 12 mm away from the burner surface. Regardless of the type of burner used, the outer limit of the flame represents the area where there is initially complete combustion of the fuel. The size of the distance depends on the burner construction and can be referred to as a parameter of the burner. The space between the burner and said characteristic distance is referred to in the description and in the claims as the combustion area or characteristic combustion area of the burner.

The by the combustion of the burner 1 supplied Heat generated by fuel is transferred to a heat exchanger design Lon of a certain type of construction, as it is in the Drawing is designated by 5, for example. The heat exchanger construction consists of a plurality of tubes 6 which, in a cylindrical arrangement, the burner 1 surround. The tubes 6 have at their upper ends with a connection head 7 and at their lower ends with connection structures Ö connection which are connected to an inlet line and an outlet line 10, so that to be heated V / ater can be guided upwards and downwards through the series of arrangements of pipes 6. to increase the effectiveness and the efficiency of the heat transfer from the hot gases to the water in the Ronren 6, the tubes are embedded in a support structure 11, which consists of small steel bodies or steel balls, the are soldered to each other and to the tubes 6 and fill the space between the tubes. Details of the support structure 11 and the head connections 7 and O do not form part of the present invention, so a closer look Description in this regard is unnecessary.

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The water is flowing through at such a rate .Va.r: i.e--: exchangers guided that the warm - -. Exchanger construction reached maximum temperature, jeüeniaixs remains below the temperature range in which an instantaneous Connection of konienmonoxyd with üauersioff zu Liohlendioxid takes place. This temperature range lies ^ υ on the order of a few hundred degrees Celsius and below about 540 ° C., during -. Presently a tuned one <Värmeaustausciiergestaltung was described, first it sicu, that any known types of arms from thousands of brazen are used whose normal operating temperature is below the combination temperature of carbon monoxide unu Oxygen lies.

"In high-power burners, for example as described above, a gas temperature is reached in the characteristic combustion range of the burner, which can be about 1540 C or above and is above the temperature at which carbon dioxide already dissociates to carbon monoxide and free oxygen Therefore, the normal gases flow out of the characteristic combustion area, they contain a considerable amount of coal monoxide, although during the combustion process all the carbon in the gas that has been burned has been burned into carbon dioxide, as is the case with burners with a low power density and high efficiency as described above Type of construction is the case.

Up to now the only possibility was to add energy to the hot gases before they came into contact with the heat exchanger withdraw, in the radiation. The speed with which such a heat extraction takes place, however, is so slow that that at normal gas velocities on the way of the gases from the characteristic combustion area to the heat

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exchanger the temperature of the hot gases above the recombination temperature on carbon monoxide and free oxygen remained, namely above about 1370 ° G. Here, however, the "Värmeausteausher withdrew heat energy from the neisse gases so quickly, that the temperature of the gases too quickly the recombination area went through so that there wasn't enough time for one substantial recombination remained. lÄari could do this as Designate shocking effect at which the tendency to Recombination due to the on relatively lower The heat exchanger at the temperature was quenched.

firfinduiijs ^ em, however, it becomes too. or mentioned deterrent effect ung by the fact that in the space between the burner and the heat exchanger 5 a perforated Screen or a .ritterarxiges screen 12 is arranged. That Sieve 12 consists of relatively coarse: One heat-resistant wire made of a metal alloy, welcne under the name "Lantnal" is commercially available and a Chromium-iron-aluminum-Iolybdenum alloy, which is about b5; -Sisen, 30.- G / .rom, 5, - aluminum and traces of molybdenum contains. Of course, a perforated screen or a sieve a., s another xi heat-resistant material in be arranged in the same way around the burner 1 xxerum. For example ceramic rods can be used as material for the production of the screen or screen 12.

The sieve or screen 12 lies just-on the side of the ciiarakxeris ti rope combustion area of the burner If the depth of this area is approximately 13 mm in accordance with the example given, the sieve 12 can be used in one Distance \ on about 22 mm \ on the surface of the sleeve 2 of the Burner are arranged, while the inner surface of the Y / heat exchanger 5 is again about 22 mm at a distance from the Sieve 12 is located. i an appropriate position of the sieve 1 '

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so is about halfway the distance between the Outer surface of the sleeve 2 of the burner 1 and the inner surface of the heat exchanger 5, it being assumed that aas Sieve in this position outside the characteristic combustion area of the burner is located.

The combustion products of the burner 1 are forced on a path through the heat exchanger, in which the space between the burner 1 and the heat exchanger 5 is formed by an upper plate 13 and a lower plate is completed. The sieve or grid 12 is between these

fe plates have a heat-resistant, low thermal conductivity owning block 15 supported, which is attached to the plate. A corresponding block or an intermediate layer 16 made of the same material is attached to the lower plate 14. A suitable material for parts 15 and 16 is asbestos, which is also effective as a sound-absorbing material and produces undesirable noise The reason for the passage and the burning of the gases is suppressed by or in the facility. The block 15 can be in its position must be secured by means of a number of brackets 17 which are welded to the plate 15. The grid or sieve 12 is suspended from block 15 by means of some Ilaken Io that extend through block 15. To this

In this way, it is achieved that very little, if any, heat is transferred from the screen or screen 12 to the surrounding structure, since it is desirable to keep the screen or screen 12 at substantially uniform temperature in all of its parts. The lower end of the grid or screen 12 is supported by means of the wire ends 19 which protrude from the lower edge of the grid or screen 12 and are easily pinned into the surface of the block 16. Although it is not necessary to fasten the block 16 to the lower plate, it can, if necessary, be fastened in the same way as is provided for the block 15.

109836/0912

The grid or screen 12 absorbs a certain amount of heat durcii radiation from the hot gases in the characteristic Combustion area, but the grid or sieve is mainly caused by those coming out of the combustion area neißen gases flowing through the mesh of the grid. As already mentioned, occur on the grid or screen 12 im "essentially no heat losses due to heat conduction to the adjacent components and for this reason the heat must be dissipated essentially exclusively by radiation take place. The temperature of the grid or screen 12 therefore rises to a temperature of about 1370 C, this being the same Temperature occurs substantially uniformly over the entire grid.

At the temperature mentioned, the 'amount of heat, which the sieve or grid ·. on the white gases is supplied, equal to the amount of heat which the grid or sieve gives off by radiation. It can thus be seen that the grid or sieve 12 is called the one passing through the grid Cools gases uniformly by about 167 degrees Celsius. This is enough to bring the temperature of the gases to around 1370 C press down which value is within the recombination temperature range of carbon monoxide and free oxygen. As a result, it connects about in the Carbon monoxide present in hot gases rushes with the free oxygen, which is caused by the previous dissociation had been released from carbon dioxide and within an extraordinarily short distance beyond the grille or Sieves 12 a complete recombination of the carbon monoxide has occurred, so that the hot gases which the Achieve heat exchanger 5, are essentially free of KohieiS.

109836/091 2

By, the .Srfinduns; Thus, a ss: .r ίζοχφ & κχ, β Vv -ärrneaustauacnerereinriCiitung x.oher leis uunirsdiexixe and ionic efficiency is created, with which the exhaust gases are essentially free of Iioiilemnonoxyu ^ enaluenes, but there is no need for any loss of efficiency with regard to the degree of efficiency is to be named.

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103836/0912

Claims (7)

Claims ; Rärmeaustauscnereinricntung with a serving for burning carbonaceous fuels, which is assigned to a combustion area lying in its jnane and is arranged near a heat exchanger whose operating temperature is below the combination temperature of carbon monoxide and oxygen, characterized in that between the combustion area and the heat exchanger (5) a 'heat sink (12) for the extraction of thermal energy from the vert. Emission products is intended to lower their temperature to the above-mentioned combination temperature, in such a way that during operation essentially all of the carbon monoxide present in the combustion products forms carbon dioxide with oxygen before it reaches the heat exchanger. 2. Heat exchanger device according to claim 1, characterized characterized that the heat sink \ on a perforated, formed from nitzesesistant material existing component is that in the flow path of the combustion products between the said combustion area and the heat exchanger (5) is arranged. 3. Vrärmeaustauscheinrichtung according to claim 2, characterized in that close to the iiitzebeständigem material existing, the heat sink (12) forming component thermally conductive components of the heat exchanger (5) are arranged, against which the component ordered from heat-resistant material is insulated with respect to the heat transfer in such a way that it is heated by the combustion products during operation to a temperature at which the Wa neverluste of the component, which is best made of heat-resistant material, are essentially only caused by radiation. - 11 - 109 836/0912 4 · Heat exchanger device according to claim. 2 or 3, characterized in that the burner (1), the component made of heat-resistant material (12) and the heat exchanger (5) have a cylindrical shape and are concentric to one another are arranged. 5 · Heat exchanger device according to one of the claims 2 to 4, characterized in that the component consisting of heat-resistant material is a heat-resistant metal alloy contains. 6. Heat exchanger device according to one of the claims. 2 to 5f characterized in that the heat-resistant Material of the existing component via one or more heat-insulating, sound-absorbing intermediate pieces (15 »16) is attached to the adjacent components of the heat exchanger (5) (l8, 19). 7. Heat exchanger device according to claim 6, characterized characterized in that the heat-insulating, sound-absorbing Intermediate pieces contain or consist of asbestos. - 12 109836/0912