DE2107872A1 - Rotary kettle - Google Patents

Description

DR.-ING. WALTER ABITZ DR. DIETER F. MORF DR. HANS-A. BROWN

Patent attorneys

Three. Patent Attorneys Abitz, Morf, Brauni 8 Munich Bi, Postfach 86010?

Munich, February 18, 1997I Postal Address 8 Munich 86, P.O. Box 860109

Pienzenauerstraße 28 Telephone 483225 and 486415 Telegrams: Chemindus Munich Telex: (0) 523992

CR-7042

E. I. DU PONT DE NEMORS AND COMPANY

Wilmington, Deleware 19898

UNITED STATES.

Rotary kettle

The invention relates to a "rotary boiler, particularly a device for maintaining a
having certain radial depth of the annular body of liquid in the boiler during operation.

Rotary boilers for generating steam are already known and have been found to have a number of Have advantages over conventional boilers.

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For example, the high centrifugal acceleration in the bowl creates a sharp, stable interface between of the liquid and steam in boiling, which is essentially cylindrical and concentric with the heated one cylindrical boiler surface. Such a boiler produces steam of high quality and a constant Flow of steam and liquid, and the boiler also works independently of the earth's gravitational field and orientation. In addition, the high speed of rotation usually used enables a heat flow that is good is above the peak of the boiling point under normal gravity.

The invention is therefore based on the object to provide a rotary boiler of the type mentioned, which is an optimal Enables use of the advantages mentioned.

In addition, the subject of the invention should be the automatic Control and maintenance of the radial depth of the mentioned body of liquid at a certain liquid level enable.

The invention is also intended to create a new device for controlling the liquid level, which is effective and foolproof in operation and greatly increased in terms of the moving parts.

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In addition, the subject matter of the invention should include, for example "be particularly well suited when carrying out the high-performance eankine process, in the case of Stirling machines, in refrigeration machines and in the generation of steam for heat exchange or chemical reactions To find use.

To solve this problem is according to the general concept of the invention a rotary kettle with an outer annular kettle chamber and an inner cylindrical liquid Skammer provided which are arranged coaxially for rotation with one another about a common axis. Of the Kettle is rotated at a certain speed to make the annular body of liquid more even radial depth to keep the · circumference of the inner surface of the boiler chamber, and a similar annular body of liquid is provided in the chamber. Radial inflow lines are also provided for the liquid from the inner chamber to the boiler chamber. Here, the flow of liquid through the inflow lines of the chamber to the boiler chamber is controlled by radial probe lines which are in communication with the chambers and automatically cooperate with the inflow lines by the radial depth of the annular body of liquid in the boiler chamber when operating the boiler at a certain height. This becomes the desired mentioned advantages achieved.

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Further advantages and details of the invention emerge from the description of some exemplary embodiments which now follows referring to the drawing. In this show:

Fig. 1 shows a cross section through the rotary boiler according to the invention, which is used schematically for implementation the approximate Rankine process is shown and further includes a turbine and a condenser;

FIG. 2 shows a section along the line 1-1 of the illustration according to FIG. 1;

3 shows a partial section along the line 3-3 in FIG. 2;

FIG. 4 shows a partial section along the line 4-4 of FIG. 1;

FIG. 5 shows an enlarged partial section along the line 5-5 in FIG. 1;

6 shows a section similar to FIG. 1 with the illustration a modified embodiment of the rotary boiler;

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7 shows a section along line 7-7 in FIG. 6;

8 shows a partial section along the line 8-8 in FIG. 6 and FIG

FIG. 9 shows an enlarged section along line 9-9 in FIG. 7.

In Figures 1 and 2 shows the rotary boiler according to the invention a cylindrical outer housing 1 with a continuous cylindrical peripheral wall 2 and side walls 3 and 4. Hollow shafts 5 and 6 are arranged on these side walls 3 and 4, through which the boiler housing 1 is supported in bearings 7 and 8 is rotatably arranged. The boiler can now be driven by an electric motor M at a desired speed the gear 9 is driven, which in turn drives a gear 10 on the shaft 6.

In the boiler housing 1 is for rotation with this a cylindrical Innenkainmer 11 is provided through a continuous peripheral wall 12, the heated boiler side wall 4 and an opposite side wall 13 is limited. As best seen in FIG can, the diameter of the inner chamber 11 is smaller than the diameter of the boiler housing 1, so that the cylinder wall 12 of the inner chamber in a certain radial distance

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stood inwards from the housing wall 2 and forms an annular boiler chamber B between them. Over and beyond the inner chamber wall 13 is arranged at a certain distance from the adjacent housing wall 3. Thus forms the haum between the wall 12 of the inner chamber and the wall 2 of the housing and between the side wall 13 and the Housing wall 3 an evaporation chamber V in the rotary boiler housing 1, This chamber V is in open connection with the hollow shaft 5, so that the in the boiler chamber B generated steam and collected in the chamber V, as' will be described in the following, through the hollow shaft 5 and a line 14 is passed, for example, to a turbine 15 from the boiler 1. Eadial wings 13a are in the chamber V between the walls 3 and 13, see Figure 4, to the Eotationsenergie of the steam to the linear output of the system when the Dampj flows out of the boiler through the shaft 5.

In a similar way, the interior of the chamber 11 is in open connection with the hollow shaft 6 through which the boiler feed line to the chamber 11, for example in the form of liquid condensate through a pipe 16 from a condenser 17 takes place, the inlet of which is connected to the exhaust steam of the turbine 15 by a line. In the ■ "■ bstand inwardly opposite the hollow shaft 6 and the Uand 4 an impermeable baffle 19 is arranged, the right-angled to the axis of rotation of the boiler housing. This baffle 19 shows a diameter that is slightly is smaller than the diameter of the wall 12, so that the

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Circumferential edge 20 of the baffle plate 19 at a distance from the inner surface the wall 12 is so that the boiler inflow from the shaft 6 around the edge 20 of the baffle plate 19 in the Main part of the chamber 11 can be done. But, as you can see from the drawing, the distance between the edge is 20 from wall 12 is less than the radial height or depth of the annular body of the boiler inlet flowing into the Chamber 11 is maintained. Radial wings 19a are

I provided between the baffle plate 19 and the housing wall 4, as shown in FIG.

The boiler housing 1 is driven by the motor M at a certain speed which is calculated in such a way that a centrifugal force is generated which is necessary so that the inflow is evenly distributed around the circumference of the chamber B; which is in contact with the inner surface of the housing wall 2, and also to provide the overall g desired boiler or vapor pressure which is matched to the radial length of the foot of the liquid between the baffle plate IS and the housing wall. 4 The area between the liquid and the vapor in the chamber B is highly stable and essentially cylindrical and concentric with the axis of rotation of the vessel. In a similar way, the boiler inflow into the chamber 11 is kept uniform on the circumference of the inner surface of the cylindrical chamber wall 12.

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".: Β r'iviia ^ sn ^ ugft- ya. una .a sine cei a ^ esce-'rl ·: - ■ '? ":' _ _; rt vünscnensver", nc gene radial fluid;? -

a respective unit of condensed Tllssijkei * ir. ien Boiler is required by the following expression

_2 -2

H 1

is. v aie Aessei-wir ^ e ^ gescr / .vincigjieit, g · cie i bescr.leur.i ^ un «,?» - the Hadius ν cn the axis of rotation of the lisssel to the liquid level. y according to figure *, and?. ^, is the radius of the axis of rotation zn the liiTsau. σ i figure '. There is a pressure increase between the customer satcr * " and the chamber 7 at:

where d is the density of the supplied liquid. The work indicated on the blades 13a in the chamber Y "with the radial flow of the steam from the boiler is always equal to or greater than the pumping work". "/," If the friction is neglected Work is generated by the internal flow of steam, but the pressure drop is also much greater than with the arrangement of the blades.

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SAD OBIQINAL

A special feature of the invention still exists in the construction and the arrangement required for the I \ esselzufiusE from the Kazner 11 to the Xesselkaizmer E unc for automatic Maintaining the liquid level in the Steam chamber provided in the desired radial height or depth which is indicated, for example, with χ in the drawing.

According to FIGS. 1 and 2, the boiler flow from the hemmer T1 to the chamber B takes place through several radially lying lines 21 in the cylindrical chamber wall 12, and these are at the same distance on the circumference in order to ensure a barrel compensation in the boiler. The radial inner emits of the lines 21 are as shown. / aligned with the inner surface of the chamber wall 12 angeorcf-. net "and the radial Aussenetxden the lines 21 are" arranged / 1 7V ^, but they ma x s under the Flüsaigkeitsniveau, "~ ^r in J. Ibstand tone of the inner surface of the wall 2 in the inn eh ■ V ^ rf! so that the Ausaeneitden the MiMigen 21 in the ring-shaped · '^ £ Flussi eitsk: örper eiiigttaiicht q ^ d Toti dt 3 * m -?' - * _Χ ^'Λ covered SMD, the gleichmässtg-to AEIE Iimenf Vueke - the · · .-- '■ Kessslwand 2 through your ^ hung ^; aes boiler is held ·.

The liquid body in the cone chamber B of the housing 1 is now at a certain level χ by several maintain radially lying tubes or pipes 22, which is also in 4er Hmfangswa.nd 12 der

9 -

SAD ORIGINAL

11 are arranged. How is the ir'aile of the air flow lines 21 are the lines 22 at the same distance from each other and from the lines ? ' geaalten to ensure mass balancing in dec teasel. It is important au Note that the radial äussenenden the lines 22 χ BICs a r.adiue dec bestirten Iii7eaus of Fiüs3igkeit3körpers in Kac ^ B it go It is s. The Innenenöen of the lines 22 are open to the inner space of the Saisner 11 and extend radially inward to a point which is held at a substantial distance from the surface of the annular body of liquid ac circumference of the Samoer 11.

The ring-shaped body of liquid in the chamber can now be heated to the desired boiling temperature, for example by burning a suitable aerosol air gas in the combustion chamber 23, as shown in the drawing. The Brenakanißer 23 is stationary and has an annular shape, <He eLas Dr # hk housing 1 uQschlieast and a raai & len A ^ staßd at • the Viaac 24 which includes _r and üarabe-rriinaus is 3ie tpt'AL-stanä. Ton the ringföraigeri crosswinds 25 and 2c held, with the Zulatat called detached inner liner 27 and 2S, which are arranged just above the circumferential edge of the opposite string walls 3 and 4 of the Ks33§! G £ imisee 1. The VerbrennuQgskaaten 23 rents a ring-shaped board chamber C, which surrounds the housing 1, and the outer surface of the liafangswaud 2 is $ it B * h? ^? En am

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Λ Ο

viisfang llo ^ enceri radial wings or ribs 2S ^- provided to 3 _: &>: iiaale .Mrksa & keit des Vi ^ rseübergaugs von der Brenn-> iiir-Ti.er C su 5e-r. To achieve annular liquid body in the. Kesfse! housing so that the liquid is heated to the desired boiling temperature.

Ber fuel for combustion in the chamber is 0 ä can now einge- tangentially into the chamber through a Lüse 30 which sit the fuel of a certain flow and a certain Lruck means of a duct 3 'is supplied. In addition, air and the fuel are mixed into the combustion chamber Z via several Xar.r.Ie 32 in an essentially segment-shaped circumference 24 of the combustion chamber Z. The ducts 32 are enclosed in a hood-shaped construction 33, which forms a plane chamber 34 into which the air is introduced through a line 55 by means of a pump or a compressor (not shown) with a pressure and a volume that is necessary for effective combustion to % heat the liquid in the housing to a certain degree is required temperature. the combustion of the fuel-air mixture extends substantially over the entire "circumference of the Lrehkessels and the Restproöukte of the combustion gases are discharged through an outlet or exhaust conduit%. Lie stationary baffle plate 37 having projections 38 for a corresponding intermediate seat with the * wings or flaps 29 on the rotating · boiler housing 1 is transverse to the combustion chamber C between

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the fuel nozzle 30 and the outlet 36 arranged, see Figure 3, to a renewed circulation of the fuel gases through the To prevent combustion chamber.

In operation, the motor M drives the boiler housing 1 at a certain speed, and the ring-shaped Liquid body in the boiler chamber B is on the desired boiling temperature heated by a combustion of the fuel-air mixture in the chamber C, whereupon the vapor generated by the boiling liquid is collected in the chamber V and passed through the shaft 6 as well as the Line 14 is delivered to the turbine 15, which is thereby driven in a conventional V / eise.

If the liquid in boiler chamber B is evaporated in the described manner, the height or depth of the annular body of liquid in the boiler increases, as a result of which the radial distance of the surface to the outside is lowered compared to the aforementioned specific level χ, which is shown in the drawing is shown, with the result that the radial - ^'1 U s SEN to the lines 22 not covered and thus open to the steam in the boiler chamber B'sind · covering or opening of the outer ends of the lines 22 allows the flux enters the boiler chamber in the lines 22, and part of the steam under pressure in the chamber B now flows inwards through the lines 22 into the chamber 11, whereby the pressure in this chamber increases and the liquid in the chamber 11 flows outwards.

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sen is brought through the lines 21 to Abf Hessen. As a result, the body of liquid in chamber B is restored filled up until the surface has reached the specific level χ again. By the return of the liquid surface at the level χ the outer ends of the lines 22 are closed and a further current through the lines to the boiler housing until the surface level is shifted again in the described manner to the Open the outer ends of the lines 22.

This play between the fluctuations in the surface level of the liquid around the outer ends of the pipes 22 to close and the liquid flow through the lines 21 to fill up the boiler liquid and the To restore the level is essentially continuous, so that the liquid level in the boiler housing 1 automatically at all times during operation essentially is continuously held on the line χ shown in the drawing. The radial depth or Thickness of the annular body of liquid in the chamber. j B is determined by the radial distance between the Outer ends of the lines 22 and the inner surface of the housing wall 2, and therefore the radial depth of the body of liquid in the chamber B and thus the radial position of the level line χ according to Figure 1 and if necessary can be controlled by changing the distance between the outer ends of the lines and the

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Inner surface of the housing wall 2.

The liquid supplied to your kettle in chamber 11 is replenished by the shaft 6, in the present case in the form of a liquid condensate the condenser 17. The exhaust steam of the turbine 15 is fed through the line 18 to the condenser 17, where it is in the liquid form is condensed and returned through line 16 to input shaft 6 and chamber 11 will.

Another embodiment of the invention is shown in FIGS Figures 6, 7, 8 and 9 shown. This embodiment is generally of the construction previously described similar, but differs in certain details of the construction and the arrangement described therein. In Figures 6 and 7, a rotary housing 50 is provided with a peripheral wall 51, and there are opposite Side walls 52 and 53 arranged, the latter have radial flanges 54 and 56 which extend outwardly beyond the Viand 51 and therebetween a Form space in which an outer boiler chamber B 'with several annular bead-shaped Kesael sections 56 is arranged. Each of these sections 56 is tubular with circular Cross-section formed, and the sections are arranged at a distance from one another and from the wall 51 of the housing 50.

V / ie in the first-mentioned embodiment, the housing 50 is provided with axially protruding hollow shafts 5a and 6a.

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see through which the housing 50 in the bearings 7a and 8a is rotatable. The housing 50 is now driven by the electric motor Ι · ί 'with a "certain speed over a Gear 9a driven, which in turn drives a gear 10a on the shaft 6a.

A steam chamber V is arranged coaxially in the housing 50 and is delimited by a cylindrical V, ^{T and} part 57, the housing edge 52 and a wall part 53 arranged at a distance. The chamber V is in open communication with the hollow shaft 5a, so that steam is generated in the boiler parts 56 and fed to the chamber V, from where it is fed to the turbine 15a, for example, through the shaft 5a and a line 14a Radial vanes 52a are provided in the steam chamber V as in Figures 6 and 7, and these vanes have the same effect as the vanes 13a which have already been described.

The diameter of the cylinder wall 57 is smaller than the diameter of the housing cylinder wall 51 and is arranged at a distance g inward therefrom in order to create an annular chamber 59 therebetween for receiving boiler water. The -Wandteil as shown 58 spaced inwardly from the housing wall 53 and displays a diameter which is slightly smaller than the cylindrical housing wall 51 terminating in a peripheral edge 60 _T is at a distance inwardly of the Gehäuswand 51

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lies. The ring-shaped boiler filling chamber 59 is thus in open connection with the hollow shaft 6a, through which the boiler water of the chamber 59, for example in the form of liquid condensate, through a line 16a of a condenser 17a is fed, the inlet of which is connected to the exhaust steam of the turbine 15a by means of a line 18a connected is. It should be noted that similarly to the baffle 19 according to the first embodiment of FIG Diameter of the wall 58 is held so that the distance between the peripheral edge 60 and the housing wall 51 is smaller as the radial depth or height of the kettle body of the kettle fill fluid in chamber 59. In addition, radial Wings 58a are provided in the liquid-filled support between the wall 58 and the housing 53, such as shown in Figure 8 to exert a rotary movement on the liquid to be supplied, as it is similar to the already described wing 19a acts.

The boiler fill water is directed from chamber 59 to each section 56 through conduits 61 formed in the cylinder wall 51 and extend inwardly opposite the parts 56. In the embodiment according to the figures 6 and 7, a plurality of leads 61 are provided for each part 56, and these leads are equally spaced apart arranged on the circumference to ensure mass balance. The radially inner ends of the lines 61 are arranged in alignment with the inner surface of the chamber wall 51,

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and the radially outer ends of the lines are kept at a distance inward from the wall of the parts 56, but they end below the level line x ¹ , so that the outer ends of the lines are submerged and closed by the annular body of liquid attached to the Inner surface of the boiler parts is preserved by the rotation of the housing 50.

That generated in parts 56 by boiling the liquid. g vapor is passed into the chamber V by lines 52 which correspond to those nach'den Figures 6 and 7. FIG. A plurality of lines 62 are provided for each boiler part 56, and identical lines 61 are arranged at the same spacing on the circumference of the housing 50 in order to ensure a mass balance. The body of liquid in each part 56 is held at the particular level x 'by probe tubes 63 which are constructed and arranged in the manner shown, with several such tubes arranged for each boiler part and equidistant from one another on the circumference opposite the other conduits are held, | to ensure mass balance again. As in the case of the probe tubes 22 in the first embodiment, the radial outer ends of the lines 63 are arranged at the radius of the specific liquid level x ^f , and their inner ends are open to the interior of the chamber 59 inwardly beyond the level of the liquid body.

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Al

This annular body of liquid can now be heated in each part 56 up to the required boiling temperature to generate steam as described in the first embodiment. Accordingly, it is not necessary the description of the combustion system according to the figures 6 and 7 and the parts identical to those shown and described in FIGS. 1, 2 and 3 and corresponding reference numerals with the additional letter a have been given to the corresponding parts.

The mode of operation in the embodiment according to FIGS. 6, 7, 8 and 9 is essentially the same as described above and therefore does not need to be repeated. It suffices to establish that the lines 61 and the lines 63 act in the same way as the lines 21 and 22 in the first exemplary embodiment, that is to say automatically, in order to move the area of the liquid body in each part 56 on the desired plane x ¹ according to FIG. 3 to keep. In addition, in order to determine the work W which is required to pump a unit weight of the liquid condensate into the boiler according to this embodiment, the aforementioned formula can again be used, where K _{1 is} the radius of the axis of rotation of the boiler to the liquid level y ¹ , which is shown in Figure 6, and E2 is the radius from the mentioned axis of rotation to the level line X ¹ in JCigur 6.

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"in an important feature of the rotary kettle described is its ability to generate high quality steam. The centrifugal force caused by the rotation and the liquid act together, separating the trapped liquid droplets from the vapor in to improve chambers V and V. This feature is particularly important in the case of a rotary kettle that is there It is used where liquid inclusion in the steam is undesirable, such as when driving a turbine. i

While illustrating certain embodiments of the invention and have been described, it should be emphasized that the invention is not limited by this disclosure should be. Rather, it is possible for the person skilled in the art to make modifications and changes to these exemplary embodiments, without departing from the basic idea of the invention.

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Claims (14)

CR-7042 ZO E. I. du Pont de Iemours February 18, 1971 and Company Claims ί 1st / rotary boiler, characterized by the following Characteristics: - a structure forming an annular boiler chamber (B) "; - a device for rotating this structure about the axis of the boiler chamber; - A device with a cylindrical liquid szufuhrkammer the coaxially inward of the Boiler chamber is arranged and rotatable with this about the axis; a device for feeding a liquid into this chamber; - a first line device for a liquid ■ power flow from the liquid supply chamber to the boiler chamber; - 20 109835/1156 CR-7042 drive means for rotating the vessel and the liquid supply chambers about the axis with a "certain speed, around an annular body of liquid with the same create radial depth and maintain that continuous on the inner surface and the liquid supply chambers is formed and creates the desired steam pressure in the boiler; and means having a second conduit system connected between the liquid supply chamber and the boiling chamber establishes a connection and cooperates with the first device to the to control radial depth of the body of liquid in the boiler chamber and essentially constant at a certain desired level. 2. Rotary boiler according to claim 1, characterized in that the first conduit means at least one having radial line, the inner end of which has an opening to the liquid body in the liquid supply chamber and the other end of which has an opening radially outward from the particular one Shows the level of the liquid of the liquid body in the chamber and is immersed in it. - 21 - 109835/1 156 CR-7042 3. Rotary boiler according to claim 1, characterized in that the second conduit means at least one having radial line, the inner end of which into the interior of the liquid supply chamber from the liquid level is open inward, and that the outer end with its opening at the desired Liquid level of the body of liquid is arranged in the boiler chamber. 4. Rotary boiler according to claim 2, characterized in that a plurality of radial lines are provided and that these are arranged at the same distance around the circumference of the liquid supply and the boiler chambers, to achieve a mass balance when rotating. 5. Rotary kettle according to claim 1, characterized in that a device for heating the liquid is provided in the boiler chamber to the required temperature for • evaporation of the liquid. 6. Rotary boiler according to claim 5, characterized in that the steam chamber GO in connection with the boiler chamber (B) for receiving the steam generated in the boiler chamber. 7. Rotary boiler according to claim 6, characterized in that the device for rotating the boiler chamber their axis is a pair of coaxially protruding hollow shafts (5, 6) - 22 109836/1156 CH-7042 on opposite sides of the construction, one of these shafts with the steam chamber (V) in Connection is and forms an outlet for the steam that is generated in the Xesselkaramer and that the other Shaft is in communication with the liquid supply chamber so that the liquid is supplied. 8. Rotary kettle according to claim 5, characterized in that the ". device for heating the liquid in the | Boiler chamber (B) has a stationary combustion box, surrounding the rotatable boiler structure and that means are provided to feed fuel and Introduce air into this box for combustion to bring the liquid in the boiler chamber to the desired level To warm up temperature. · 9. Rotary boiler according to claim 1, characterized in that the boiler chamber (B) has a plurality of annular tubular boiler sections (56) which are side by side are arranged and are provided with at least a first and f second conduit means. 10. Rotary kettle according to claim 9, characterized in that a device for heating the liquid in each Kettle part (56) is provided to the desired temperature to evaporate the liquid and that a steam chamber (V) provided with a third line device - 23 -109835/1156 CR-7042 can be seen with the boiler parts for steam passage from the boiler parts too. the steam chamber is provided. 11. Rotary kettle according to claim 2, characterized in that that the boiler parts take the place of the boiler chamber step. 12. Rotary boiler according to claim 3, characterized in that the boiler parts in place of the boiler chamber (B) (56) kick. 13. Rotary boiler according to one or more of the preceding claims, characterized by the following Characteristics: - the two V / ellen (5, 6) are in connection with the steam chamber (V) and form an outlet for the steam generated in the boiler chamber (B); - The second of the shafts is in communication with the liquid feed chamber in order to feed the liquid ; the first conduit means is provided to convey the liquid from the liquid supply chamber to convey to the boiler chamber (B); - 24 10 9 8 3 5/1156 _BAD original CR-7042 the second conduit device shows several radial probe tubes whose inner openings in the interior of the Liquid supply chambers end, specifically within the liquid level, the outer ones being open Ends with the desired level of the body located in the boiler chamber; the probe tubes cooperate with the inflow tubes to bring in the radial depth of the body of liquid to keep the chamber essentially constant and at a certain level. 14. Rotary boiler according to one or more of the preceding claims, characterized in that a device for fuel and air flow to a combustion chamber is provided to heat the liquid in the boiler chamber to the desired temperature. -25 - 109 835/1156 Blank page