DE3329435A1 - DEVICE FOR REFORMING FUEL - Google Patents

Description

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Device for reforming fuel

The invention relates to a device for reforming fuel.

The device for reforming fuel is a device based on hydrocarbons based fuel. is converted into a gas, the main component of which is hydrogen ^

Many devices for reforming fuel of the above type have been installed in chemical factories. . _:

In order to make the invention better understood, it will be helpful to refer to previous devices for reforming of fuel to describe in detail.

FIG. 1 shows a conventional device for reforming fuel. The best known reforming device is a steam reformer, in which the fuel conversion takes place by gradually adding steam to the fuel such as CH ^, or a similar, whereby the mixture of fuel and steam is forced to form a catalyst layer at an elevated temperature happen, for example in a range of from 75O ° C to 900 ⁰ C in order to convert it into a gas containing hydrogen as a main component, and wherein the residual carbon monoxide with the aid of a CO - converter is converted to CoO and COp then high a

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To obtain the degree of unity of the hydrogen gas, is deducted.

In particular, fuels such as OH ₂ , or the like, which are introduced from a storage container outside the fuel reforming system, as shown in FIG Fuel and steam of a plurality of pipes filled with a catalyst, which are installed in the steam reforming furnace 3, is supplied. The tubes 4 filled with the catalyst are heated up to an excessive temperature in the range from 750 ⁰ to 900 ⁰ C by the radiant heat, starting from the wall surfaces of the steam reforming furnace.

The wall surfaces are heated by operating a number of burners 5.

During the mixture of fuel and steam the catalyst layer in each of the with the catalyst Passing filled tubes 4, it is forced to reform itself into a gas containing hydrogen. This reformed gas 6, which has hydrogen as a main component, is a heat exchange subject in the heating tube 7, in which the heat exchange between the refo.miertGn £ as 6 and the Water 2 'is effected, which is delivered to the heating pipe 7 from a feed container which is outside the Fuel reforming system is arranged. The gas is then passed into a CO converter 8, in which converts the residual carbon monoxide to COo

Is initiated. After leaving the CO converter 8 the reformed gas passes into a COo ~ absorbing tower 9 »in which the residual carbon dioxide is removed from the gas.

The fuel reforming system turns into hydrogen taken with a high degree of purity. On the other side is the combustion gas, 11, that rises from the steam reform furnace subjected to a heat exchange in the part 7 * in which the heat exchange between the combustion gas 11 and the steam 2 generated by the heating pipe 7 »is effected and after that the combustion gas is released into the exterior Exhale atmosphere.

However, the conventional fuel reforming apparatus constructed as described above has Kind of the following disadvantages:

(1) The 4-im tubes filled with a catalyst Steam reform ovens are exposed to a very high temperature, which is why they are heat-resistant metallic material from which they are made

is forced to work under critical conditions.

For this reason they tend to break if they have any locally increasing thermal Are subjected to stress or an unbalanced temperature distribution. For this reason, the steam reform furnace is characterized by a significantly reduced thermal Resilience from and to ensure that

the thermal load capacity is evenly distributed over the furnace, so is the latter in larger dimensions with a larger number of burners attached to the wall surfaces, built.

A conventional steam reform oven is similar manufactured at a high cost and with a large space required for its installation .

(2) After exiting the catalyst-filled tubes 4, the combustion gas is usually that Subject to heat exchange in a heat exchanger, in which the heat exchange between Combustion gas and water (steam) is effected, but no heat recovery in the lower range Temperature takes place in the flue. A conventional steam reform oven will be similar operated with lower thermal efficiency.

(3) To ensure that the furnace is at a reduced thermal load is operated and that the evenly distributed therein with the Catalyst-filled tubes as usual indirectly heated by heating the furnace walls made with refractory material are lined, the furnace walls are heated by a number of burners. With a view to protecting the refractory material, there is a need to control the rate of reduce temperature changes when the oven

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starts or stops operating.

(4) The minimum load capacity is usually given as 50% or more or less, which is why the furnace with a significantly reduced output and only with many difficulties is operated,

(5) As the conventional steam reform furnace for Operating conditions at normal pressure is designed, it is built in larger dimensions. Furthermore, as soon as this has a negative pressure, a compressor is necessary (Blower).

Thus, the invention takes into account the aforementioned disadvantages of a conventional fuel reforming device. It is the object of the invention to provide a device for reforming fuel create which has excellent operating characteristics and can be manufactured at low cost can.

This object is achieved according to the characteristic of the preamble 1, preferably resulting in embodiments from the parent claims.

The characteristic features of a device according to the invention for reforming fuel are the following:

(1) It is built in smaller dimensions with a minimized space required for

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Installation is and is operated at a lower cost.

(2) There is an effective heat recovery from the exhaust gas, which is why the device at is operated with a high thermal efficiency.

(3) It starts or stops its operation in a very short period of time.

(4-) You can use much reduced thermal Load operated.

A large number of research and development work is required to complete this goal direction carried out for this purpose. As a result of this research and Development work. It was found that the device can be sufficiently completed by using a liquefied layer system in the fuel reforming device in which a number of filled with a catalyst Pipes is arranged in the fluidized layer so that they can be heated by the latter. Furthermore, there is an air preheater in the low temperature area in the flue duct through which the exhaust gas which comes from the steam reform oven is attached .

The air preheater serves as a heat exchanger in which the heat exchange between the combustion gas and the combustion air is effected for heat recovery.

In essence, in accordance with one aspect of the invention, there is an improved fuel reformer of the type proposed which contains a plurality of catalyst-filled tubes which are used for this purpose are suitable to be heated by heating the outside to an elevated temperature, so that Fuel is reformed to gas, which contains hydrogen as a main component. The fuel passes through each of the pipes filled with a catalyst, the improvement being that the tubes filled with the catalyst are arranged in a fluidized layer.

Furthermore, in accordance with another aspect of the invention, there is an improved fuel reforming apparatus proposed of the aforementioned type, the improvement being that the with the catalyst-filled tubes are arranged in a fluidized bed and a heat exchanger is attached to a predetermined point in which the heat exchange between the outflowing Combustion gas and the incoming combustion air is effected.

Still in accordance with another aspect of the invention, an improved fuel reforming apparatus proposed of the aforementioned type, the improvement being that the with the catalyst-filled tubes are arranged in a fluidized layer and a recirculation (Circulating air) - passage through which part of the combustion gas, taken from the exhaust duct, is

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Forces is to recirculate in the pressure-tight state.

Furthermore, in accordance with another further aspect of the invention, there is an improved fuel reforming apparatus proposed of the aforementioned type, the improvement being that the tubes filled with the catalyst in one fluidized layer are arranged, which is composed of non-combustible material to be fluidized and a plurality of tube burners are arranged above the bottom of the liquefied layer .

Furthermore, according to yet another other Aspect of the invention is an improved fuel reforming apparatus proposed of the aforementioned type, the improvement being that the tubes filled with the catalyst in Form a double-walled tube are formed.

Furthermore, it is proposed according to yet another aspect of the invention of the type mentioned above, that the improvement is that the fluidized layer is so constructed in nature is that it works in the pressure-tight state, and a gas turbine is attached to a predetermined location which is powered by combustion gas.

The invention is described in connection with accompanying drawings.

Pig. 1 schematically shows a conventional fuel reforming apparatus;

2 schematically shows a fuel reforming device corresponding to a first off

embodiment of the invention;

Fig. 3 shows a fuel reforming device according to the second embodiment of the invention; and

4 shows a fuel reforming device

according to the third embodiment of the invention;

Fig. 5 is a plan cross-sectional view of a Steam reform oven in a conventional Fuel reforming device;

Figure 6 is a cross-sectional plan view of a steam reforming furnace in a fuel reforming apparatus according to the invention;

Fig. 7 is a vertical cross-sectional view of a Fuel reforming device according to the

Line I-I in Figure 2 .;

Fig. 8 schematically shows a fuel reforming device according to the fourth embodiment of the invention;

Fig. 9 is a partial vertical cross-sectional view

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which shows schematically how the plurality of tubular burners is arranged in the fluidate layer of the fuel reforming device according to the invention;

Fig. 10 is a partial plan view showing how the tube burners are arranged in relation to the plurality of tubes filled with the catalyst in the fluidized bed ;

Pig. 11 (a) shows schematically how the fuel

and the combustion air are temporarily mixed with each other before they enter the pipe, burner arrive.

Figure 11 (b) shows schematically the need to provide a perforated manifold plate for the conventional fluidized bed;

Fig. 12 (a) shows a vertical cross-sectional view a fuel reforming device according to the fifth embodiment of FIG In accordance with the line B-B in Fig. 12 (b); .

Fig. 2 (b) is a cross-sectional view of a fuel reformer according to the

Line A-A in Fig. 12 (a);

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Prop. 13 (a) is a vertical cross-sectional view a double-walled tube filled with a catalyst, which is used for a fuel reforming device is used according to the invention;

Fig. 13 (b) is a cross-sectional view of a

double-walled tube filled with a catalyst according to line C-C in Mg. I3 (a);

Fig. 13 (c) is a cross-sectional view of a double-walled with a catalyst

filled tube according to line D-D in Figure 13 (a);

Fig. 14 shows a diagram which shows how the Temperature through the double-walled tube of a power plant filled with a catalyst

pulp reforming device shown in FIG Figures 13 (a) to (c), is distributed; and

15 shows schematically a fuel reforming device corresponding to the sixth off

embodiment of the invention.

The invention will now be described in detail with reference to the accompanying drawings, the preferred one Represent embodiments of the invention.

A first embodiment will first be described with reference to FIG. 2.

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In the drawing, the reference number 3 denotes a steam reforming furnace, and the reference number 12 denotes a fuel pipe that extends horizontally above the steam reforming furnace 3 extends to thereby filling fuel into a large number of pipes filled with catalytic converters.

The reference number 13 denotes a mixer, which is arranged at a point in the middle of the fuel pipe 12, so as to fuel with Mixing steam. The reference numeral 14 denotes a steam supply pipe which is located between the mixer 13 and the steam heater 27 is located to connect the former to the latter, so that thereby Steam is introduced into the fuel flow.

Furthermore, the reference number 15 indicates the collecting inlet der Rohr.an, which is attached in front of the pipes filled with catalyst, so as to the fuel pipe 12 to connect to the pipes 4 filled with the catalyst, so as to mix the fuel and to fill steam into the tubes filled with the catalyst. The inlet manifold I5 is above the Steam reform furnace 3 arranged, the reference number denotes a plurality of with the catalyst filled tubes, each of the tubes within a fluidized bed 24 in the steam reforming furnace 3 stands upright.

Reference numeral 16 denotes the AuslaßsammeIrohr, which is arranged behind the stuffed with the catalyst tubes 4 to collect therein the reformed & ^a s containing hydrogen as a major compo-

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Contains component and which comes from the pipes M- filled with the catalyst after the end of the reforming reaction.

The outlet header 16 is below the steam reforming furnace 3 arranged. Numeral 17 denotes the reformed gas pipe, which extending from outlet manifold 16 to thereby supply reformed gas from the reforming system to steer.

The reference numeral 18 denotes a compressor (fan) which is arranged outside the steam reforming furnace 3 in order to direct highly pressure-tight combustion air to the burner 5.
The reference numeral 19 denotes an air preheater which is attached at a position which is arranged downstream of the compressor (fan) 18 and in the middle of the air duct 20 in order to preheat the combustion air therein by heat exchange between the combustion air and the hot exhaust gas.

The reference numeral 20 denotes an air line through which the compressor (fan) 18 with the Preheater 19 is connected, the latter being connected to the chamber 21 for combustion air, so as to To direct combustion air to the combustion chamber 21, which is thereby arranged outside of the steam * Reform-Qfens 3 is. The reference number 5 denotes a burner on the outer wall of the steam reform oven is attached and the reference numeral 21 a combustion

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air chamber in which the combustion air is collected and previously backed up into the burner 5 to arrive.

Reference number 22 denotes an air distributor in the lower part of the steam reforming furnace 3 is arranged so that the air flows upwards through a number of holes in the air manifold 22 flows and is then evenly distributed to form a fluidate layer 24.

The reference numeral 23 denotes an air chamber, which is arranged below the air distributor 22 in the steam reforming furnace and the reference numeral 24 is a fluidized layer for heating a plurality of tubes 4 and 4 filled with a catalyst a steam heater 27 is located in the steam reforming furnace 3 and the reference numeral 25 denotes one free edge section in the steam reform oven 3

Reference numeral 26 denotes a feed water inlet manifold in which the water to be heated is conducted.

The feed water inlet manifold 26 is connected to a heating pipe 7, which is located within the Steam reform furnace extends.

The reference numeral 7 denotes a heating pipe, welehes in the duct section in the steam reform oven 3 is arranged to guide the steam therein. Numeral 27 denotes a Steam heater that extends in the vertical direction in

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the area between the side wall of the steam refopu oven 3 with the burner 5 attached and the tubes filled with the catalyst 4- extends so as to heat steam generated in the heating pipe 7 therein.

Furthermore, the reference numeral 28 denotes an exhaust duct through which the duct in the steam reforming furnace 3 is in connection with the air preheater 19 so that the combustion gas in the latter can be initiated.

The reference numeral 29 shows a vent which is arranged downstream of the air preheater 19 in order to thereby releasing combustion gas into the air.

Next, let's look at the operation of a fuel reforming device are explained in accordance with the construction described above.

The from a fuel tank, which is arranged outside of the fuel reforming system is, introduced fuel flows through the fuel pipe 12 and enters the mixer 13 in which it is mixed with steam supplied through the steam supply pipe 14-.

The mixture of fuel and vapor then goes to the intake manifold I5 ·, which is above the one with the Catalyst-filled tubes 4 is arranged, transported so that it is evenly distributed in the latter is.

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-As the mixture flows down through the interior of each tube filled with the catalyst, it is heated to an elevated temperature by heat transfer of the fluidized layer 24, whereby the mixture is thermally converted to produce reformed gas containing hydrogen.

The gas produced in this way, which contains hydrogen as its main component, is collected in the outlet manifold 16 collected below the hole filled with the catalyst and then to the next, led to the reformed gas delivery pipe.

On the other hand, the burner 5 is supplied Combustion air is first compressed by a compressor (fan) 18 and then in the air preheater 19 heated while the heat exchange between compressed air and combustion gas is effected. The air preheated in this way is fed to the combustion air chamber 21 via the air line 20 in order to to burn the fuel introduced into the burner 5.

Part of the compressed air reaches the air chamber 25 and then flows upwards through the distributor plate 22 into the combustion chamber, whereby the material to be fluidized filled in the combustion chamber is liquefied to form the liquid layer 24.

The combustion gas enters the rear exhaust duct via the free side part arranged above the fluidate layer 24 in order to remove the water,

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that through the heating pipe 7 from the feedwater inlet manifold 26 flows to heat. It then flows into the air preheater 19 via the exhaust duct 28. After the heat exchange with the combustion air in the preheater 19? becomes the combustion gas vented through the trigger 29 into the air. Water and / or steam, heated in the heating tube 7, flows into the steam heater 27, in which the water is completely evaporated. The resulting steam is conveyed to mixer 13.

Next, FIG. 3 shows schematically a fuel reforming device according to the second Embodiment of the invention. In this embodiment, the steam reform furnace is in two fluidat- layers 24 divided into an upper and a lower one. For such an arrangement the required Space for installing the device can be substantially limited, which is why this embodiment preferred when they are installed within a strictly limited space target.

FIG. 4 shows schematically a fuel reforming device according to a third embodiment of the invention. In this embodiment the exhaust duct 28 has an inlet duct 30 for recirculating gas, which extends from the duct 28 to branches off a point upstream of the preheater 19 and. a compressor (blower) 3I for recirculating air is located on the inlet line for recirculating gas to compress the recirculating gas.

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Further, a recirculated gas outlet duct (32) extends between the compressor (blower) 31 and the air chamber 23 so that the combustion gas is recirculated through the fluidate layer via both the recirculating gas inlet 30 and the outlet duct 32 as it is recirculated from the compressor (Blower) y \ is compressed.

This is used in a fuel reforming device of the type mentioned above, a part of the combustion gas into the inlet duct 30 for recirculated gas withdrawn and then via the recirculation compressor (Blower) 31 and the outlet duct 32 for recirculated Gas is passed into the air chamber so that a fluidized layer 24 is formed in the same way as in the previous embodiments is formed.

The device according to this embodiment has the advantage that the prerequisites for formation of the fluidate layer 24 separately from which can be determined based on the combustion air.

The characteristics of a fuel molding device according to the invention are described in detail below.

(1) A major advantage of the invention is that a large number of catalyst-filled Pipes can be heated to an excessive temperature with the help of a fluidized layer. The most important characteristic of the layer to be fluidized is that an excellent effective contact between fluidized

Materials as well as between fluidized material and fluid is achieved, which is why a constant temperature distribution is easily achieved, due to the high thermal conduction velocity between fluidized. Materials as well as between fluidized material and fluid,

regardless of what temperature differences prevail within the fluidized layer see. It turns out that the filled with the catalyst tubes 4 within a constant Outside temperature are heated while they are designed to reduce the thermal load evenly to distribute, which is why the steam reform furnace has a compact design.

Since the pluidate layer has a thermal conductivity coefficient which is several times higher than that of the normal gas flow, it is ensured that the necessary thermally conductive area can be significantly reduced.

Figures 5 (a) and 5 (b) show a plane Cross-section of a conventional steam reform oven, which is set up in a chemical factory where fuel is reformed. Figure 5 (a) shows schematically that the tubes 4 filled with the catalyst are in a row with the same Are spaced from each other. Figure 5 (b) shows two rows of with the catalyst stuffed tubes that are in a zigzag shape

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are arranged.

Since the pipes filled with the catalyst 4- so are built that they reforms by the thermal energy coming from the inner side wall of the steam Furnace 3, which is lined with refractory material, is blasted, to be heated.

From this it follows that it cannot succeed the reform furnace inconsistently with thermal energy -to burden, as a uniform temperature distribution is achieved over the interior of the reform oven will.

As can already be seen from FIG. 5, one can be comparable small number of tubes filled with the catalyst arranged inside the reform furnace be.

On the other hand, FIG. 6 shows a planar cross section of a steam reforming furnace according to the invention.
As can be seen from FIG. 6, the device for reforming fuel is constructed in such a way that a plurality of tubes 4 filled with the catalyst are heated using a fluidate layer with a uniform temperature distribution over the reforming device. As a result, a larger number of tubes 4 filled with the catalyst can be arranged in contrast to the conventional device, the tubes can be arranged with a very small spacing between adjacent ones, so that the entire device can be divided into small-

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--SauDimensions is designed with a smaller one space required for it to be installed while each of the # filled with the catalyst Tubes 4 have a reduced heat conduction surface because of the aforementioned guaranteed higher heat conduction coefficient owns.

(2) In the case of a conventional fuel reforming device there is a need that the wall surfaces of the steam reforming furnace as both as a thermally insulating material to prevent heat emission to the outside atmosphere and as a thermal store, in which the radiated heat is used to heat the with the catalyst Stuffed tubes are stored, act.

This leads to the increasing thickness of the refractory material from which the furnace wall is made. However, there is a risk of damage, breakage or the like of the refractories Layers of material corresponding to the thermal stress, provided that the furnace wall has a is subject to high rate of temperature change and therefore to ensure that the refractory Material made wall surface is adequately protected, it is necessary that the rate of temperature change is reduced as much as possible, but this will reduce the fuel reforming device forced to start or stop their operations for very long periods of time.

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On the other hand, a fuel reforming device according to the invention is constructed so that a number of pipes filled with a catalyst are heated by conduction from the fluidate layer and therefore the wall surface of the reforming furnace is mainly used as a thermally insulating material for connecting heat emission to serve to the outside atmosphere, resulting in a minimized thickness of the dimensioned wall surface.

Therefore, the refractory material of which the wall surface is made is appropriately protected from damage, breakage or the like regardless of how high the rate of temperature change is calculated, that is, the rate of temperature change can be made high.
It should be noted that the rate of temperature change for the furnace wall can be made extremely high if it is provided with a number of water pipes therein to cool it, thereby minimizing the time required for the apparatus to start or stop can be.

(3) To ensure that the steam reform furnace is evenly loaded with thermal energy is, the conventional fuel reforming apparatus is required to have a number of . has burner arranged along the wall surface. On the other hand, in the force

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Material reforming device according to the invention, a fluidate layer for heating a plurality of tubes filled with a catalyst, used so that the reforming furnace is evenly loaded with thermal energy.

According to the arrangement of the furnace, in which way the burners are designed, in such a way that they only heat materials to be fluidized. Appropriately, a small number of burners with a high burning capacity are attached to the wall surface of the reform furnace, and thereby the number of burners to be attached can be reduced significantly compared with a conventional device.

Furthermore, there are groups of steam heating tubes between the burners and those with a catalyst Filled tubes arranged there is no risk of the flame coming out of the burners directly reaches the pipes filled with the catalyst, even if previously because of extremely prolonged flames unusual firing were produced. For this reason no local overheating takes place accordingly a so-called "hot spot" instead.

(4) Because heat recovery is effective by exchanging heat between the exhausted combustion gas and the incoming combustion air is effected in the area of the combustion gas outlet, where the combustion gas flows at a lower temperature, the device has a high temperature overall thermal efficiency.

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in

(5) The Pig. Fig. 7 is a schematic vertical partial view of the device according to the line II in Pig. 2. As can be seen from the drawing, the steam-forming furnace is divided into 4 chambers so that the furnace can be easily operated under suitable loading conditions. In particular, FIG. 7 shows that of the four chambers just the one at the right end is in operation (this means that it is operated in the so-called "active bed" stage) while the others are not operated (that is, they are in the stage of the so-called "sink bed ^11. This means that the furnace is operated under a workload of 25%. It is also possible to operate it under a workload of 15% or more or less by carefully controlling the working conditions operate.

(5) Since the fuel reforming device according to the invention is so constructed that a part of the combustion gas is used as a fluidizing gas for the fluidized layer by being taken out of the exhaust duct and compressed by means of a compressor (blower) and by being forced to flow in the form of a recirculation through the fluidized layers.

It is possible to operate the device with a larger number of free factors than for a conventional device is possible.

Next is a fuel reforming device according to the further embodiment

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of the invention is described with reference to FIG.

In the drawing, the reference numeral 51 denotes a feedwater line through which the feedwater is passed into an upper boiler 52. It should be mentioned that the water supply is carried out in accordance with the volume of steam (H ₂ O) required for fuel reclamation.

A part of the water that is held in the boiler 52 is conveyed via a downpipe 53 to the collecting pipes 54 below. As water flows upward from the lower header tube 57 and 58 through a plurality of bores 57 and 58, the tubes 57 and 58 extend along the inner peripheral wall of the furnace and the walls. It becomes a mixture of water and steam with the aid of the material 76 to be fluidized , which serves as a heat-conducting medium through which the heat generated by the tube burners 60 is passed on to the tubes 57 and 58. The mixture of water and steam flows to the upper boiler 52 via upper header pipes 55 and upper pipes 56.

On the other hand, the one from the upper boiler 52 incoming steam in superheater 63 overheated and this Superheated steam is then sent to a fuel-steam mixer 62 via a superheater outlet header 64- submitted. The mixer 62 is in communication with a fuel supply pipe 61 through wel-

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Fuel (e.g. OH ^) is introduced. The mixture of fuel and steam is fed into a heater 66 via the heater inlet manifold 65 initiated so that they are up to one predetermined temperature in the heater 66 is heated. Furthermore, the mixture is in a Number of cylindrical reformers 69 filled with a catalyst above the heater outlet- laßsammelrohr 67 and the inlet manifold 68 of the Reformer initiated, so that the fuel (CH ^) contained in the mixture to the desired product, which represents hydrogen (H ~) and carbon monoxide (GO) is reformed.

A typical catalyst for the device is a vanadium-nickel based catalyst used. The catalysts typically have a tubular configuration with a Inside diameter in the range from 5 to 6 mm and an outside diameter of 16 mm and a height of 19 mm. Reformed gas is transferred from the device the outlet collection tube 70 of the reformer and the conveyor tube 77 withdrawn so that it can be used as a raw material for the fuel tank, can be used to generate power or for a similar purpose.

In the drawing, the reference number 72 denotes an air heater disposed at the upper end portion of the device.

The air flows through a combustion air delivery duct 71 into the air heater 72 while it is still has a lower temperature and the result

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heated combustion air is then passed to a fuel-air premixer 78 via the exhaust passage 73 for hot air and the hot air inlet duct.

On the other hand, the exhaust gas coming from a force value is mixed in the same way with fuel (CH ^) in a certain mixing ratio and the mixture of exhaust gas and fuel is fed into a mixer 78 via the? Outlet pipe 59, in which it is mixed with the combustion air ^ coming from the air heater ^ 2.

The mixture of fuel and air is directed to the burners 60, allowing them to burn. The heat generated by burning the mixture with the aid of the burners 60 is called. Heating medium is used to heat the reformers 69 in the presence of material to be fluidized (sand or the like) in order to reform the mixture of fuel and steam with the desired result. And it is still used as a heating medium to generate steam.

Since the combustion gas is · hot very, usually it has a temperature of more than 800 ⁰ C even after heat is recovered in the reformer 69 in the flul- ized layer, it is again as a heat source for heating the heater 66 for the mixture of fuel and steam needed. The steam superheater 63 and the combustion air heater 72 and the aforementioned heater

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are then removed from the reforming system.

In the drawing, the reference numeral 75 denotes a floor board on which the material to be fluidized is held.

The characteristic features of a Kraftstoll reforming device of the type described above should be listed.

(1) Sand or an equivalent non-combustible material is used as the material to be fluidized , which is why there are several freedom factors for the selective determination of the type of fuel for heating the reformers. If the material to be fluidized is combustible, only a small amount of fuel can be supplied as auxiliary fuel and the type of material to be fluidized is limited to solid fuel such as coal or the like. However, non-combustible material to be fluidized is used in a device according to the invention, and therefore its type, grain size and the like can optionally be determined as desired.

(2) As shown in Figs. 9 and 10, there are a plurality of tube burners. 60 arranged in the fluidized bed which contains a number of formers 19 (at a location near the floor board) and by virtue of such an arrangement the following advantageous features are obtained.

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(i) Eu fluidizing.es material is heated evenly. ,

(ii) A number of low capacity burners may be equally spaced within the fluidate layer

be ordered, with a small space required for this, creating a uniform Warming is achieved.

(iii) As shown in Fig. 11 (a), the tube burner 60 is in the form of an earlier mixing burner

built in which the mixture of fuel F and combustion air A, prepared in a Fuel line or a mixer, is used as fuel.

Using ' a number of tubular burners 60 for the fluidized bed ' there is no need to provide a perforated plate P (usually located at the bottom of the fluidized bed) which also serves as a distributor plate. This perforated. Plate allows air A to flow upward into the fluidized bed "as shown in Fig. 11 (b).

(iiii) Since the pipe burners above the floor board •. · At a point away from 'the latter indicated- ■ -' are arranged, it is guaranteed that the floor board is safely protected.

The invention is with respect to a fuel reforming device described, but it should

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is not limited to this, but can also be applied to a heat exchanger of the fluidized layer type or similar devices.

Next, the fifth and sixth excercises Described embodiment of the invention.

The fifth Äusführungsform the invention is daß.eine number is up to an elevated temperature overheated of stuffed with a catalyst tubes within the fluidized layer, while the maximum operating temperature of the heat source is kept below a certain size, whereby a uniform in the fluidized layer Temperature distribution is achieved,

'ever; The catalyst-filled tubes are in the shape of a double-walled tube, so d'iß an effective heat recovery is possible and that a heat exchanger arranged outside of the fuel reforming system with reduced exterior dimensions can be built, whereby the thermal effectiveness of the system is significantly improved.

On the other hand, the fifth embodiment of the invention is that a number Catalyst-filled pipes up to an elevated temperature within a fluidized layer ··. which was built up in the pressure state, are heated while the maximum operating temperature of the Heat source kept below a certain size

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with a uniform temperature-r. · ■ distribution over the fluidized .layer is achieved. The catalyst-filled tubes are built in the form of a double-walled tube, so that effective heat recovery is ensured and that the entire device is built with smaller dimensions, corresponding to the arrangement that each of the catalyst-filled tubes has a small wall thickness in order to reduce the temperature stress and to ensure low weight and low cost manufacture, whereby a device composed of a plurality of members can be transported with the aid of a trailer or a

^ c similar vehicle can be carried out.

And about the residual heat from the exhaust gas. contains, to use more effectively after it leaves the fluidized layer, which serves as a heat medium, a gas turbine is located at a point outside the fuel

2Q reform system attached.

The gas turbine is driven by the exhaust gas introduced from the device.

Figs. 12 (a) and (b) schematically show a fuel reforming device according to the fifth embodiment of the invention. The reference numeral 81 denotes a fluidized layer which, by pluidizing granular materia.l, v / ie z. B. sand, clay or the like (in which the grain size is generally in the range of 40 to x 200 microns) is formed. The reference numeral 82

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- ■ denotes an outer tube that forms the double! - · walled, catalyst-filled tube. ... The reference numeral 86 denotes an air chamber. "mer for combustion air A ₁ which is directed to the fluidized layer.

The reference number 87 identifies the gas chamber for the gas G ^ ,, which to the katalysatorgefüll7 th tubes is passed, the reference numeral 88 an inner tube, the double-walled catalyst-filled.Rohr forms.

The reference numeral 89 denotes the outlet pipe for reformed gas G £ and the reference numeral 90 a outlet header for reformed gas. Furthermore, the reference numeral 91 denotes an outlet channel for reformed gas and the reference numeral 92 a plurality of burners which are arranged at a distance from one another in the fluidized layer.
The burners 92 are built in the form of tubular burners.

Layers 13 (a) to (c) show the structure of the double-walled catalyst-filled tubes in detail, FIG. 13 (a) showing a vertical cross section of a catalyst-filled tube. Figure I3 (b) shows a cross section corresponding to the line GC in Figure 13 (a) and Dig. I3 (c) shows another cross-sectional view corresponding to the line DD in Fig. I3 (a).
In the drawings, denotes the reference number

- 33 -

82, an outer tube forming the double-walled catalyst-filled tube, and the reference numeral; 88 identifies an inner tube, which also ^{forms the same 1} , so that the catalyst 93 is placed inside the annular space which is delimited by both the inner and outer tubes 82 and 88. Nickel-based catalyst is preferably used as a typical catalyst which is characterized by the arrangement in the form of a tube having an inside diameter in the range of 5 to 6 mm and an outside diameter of 16 mm and a height of 19 mm 9 ^ denotes the porous plate holding the catalyst or a mesh-like plate which is fitted to the inner tube is contained within the inner tube so as to promote the transfer of heat.

The reference numeral 97 denotes a holding plate on which the outer tube in the vertical direction is firmly attached.

The reference numeral 98 denotes another holding plate on which the inner tube in the same direction how the outer tube is firmly attached.

Next, the mode of operation and characteristic features of a fuel reforming device should

- 34 -

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tion, built according to the type mentioned above, .. are described. ■ '"- ..

Again with reference to FIG. the air A introduced into the combustion chamber 86 burns the fuel flowing out of the burners 92 and the combustion gas generated thereby flows upward in the state of an ascending flow while creating a fluidized layer 81 within the Housing 83 forms so that the generated heat is effectively transferred to a number of catalyst-filled tubes 82, whereby'die temperature which is distributed over the fluidized layer 81 is constant. As can be seen from the drawing, an arrangement is made so that the fluidized layer 81 is applied below the plane which is located near the upper end of the catalyst-filled tubes 82, whereby the cross-section within the cavity is increased abruptly located above the fluidized layer 81 ,. which suddenly slows down the speed of the gas. As a result, the so-called entrainment phenomenon may occur. be minimized.

This entrainment phenomenon leads to such a malfunction that the material to be fluidized is torn away together with the ascending flow. This means that the additional supply of material to be fluidized is minimized. A number of tube burners 92.ist in the lower part of the f luiäisierten layer 81 arranged so

- 35 -

that the latter is operational for a short period of time where the temperature difference that is distributed over the fluidized layer is mini- ' is mated.

13 (a) to (c) show in detail the inner structure of a double-walled, catalyst-filled pipe, in which the annular space between the outer pipe 82 and the inner pipe 88 is filled with the catalyst 93 and where raw gas G> ,, which is to be reformed, is forced to flow upwards via a gas inlet line in the form of an ascending stream. While raw gas flows upwards through the filled catalyst layers, the heat is transferred to the outer pipe 88 from the liquefied layer 81 transferred so that the catalyst layer is kept at an elevated temperature which is necessary for the reforming reaction to take place. If a fluidized layer is used for the device, it is to be expected that the coefficient of thermal conductivity will be in the range from 200 to 250 k cal / m ² h °, which means that the pipe length required for heat conduction can be significantly reduced . As the hydrocarbon-based fuel gas passes through the catalyst layer, it is reformed into a gas containing hydrogen and carbon monoxide as main components until it reaches the top of the double-walled, catalyst-fed tube.

As can be seen from Fig. I3 (c), represents a multitude of baffles 95 a bridge between the

- 36 -

inner V / andung of the outer tube and the top. ren end part of the inner tube in the radial direction so that the hydrogen-rich gas - ' flows upwards through the annular space filled with catalyst, in which it gradually increases its flow changes direction by 180 ° to get into the inner tube. To ensure that the effect heat conduction through repeated steps of meeting and the change in direction of the gas flow is maximized, a number of transition pieces can be used (not shown) fixed to the inner wall of the outer tube and / or the outer one Wall of the inner tube be attached, so that the heat conduction area is significantly increased.

After completion of the reforming to a hydrogen-rich reaction gas .Gp, this flows downward through the interior of the inner tube 88 in the form of a downflowing stream. In view of the fact that the hydrogen-rich gas has a coefficient of thermal conductivity higher than that of the hydrocarbon-based gas, a heat-conductive tape 96 is made of a heat-resistant metallic material such as e.g. B. SUS J) QA- arranged in accordance with 315 or a similar in the inner tube in order to thereby maximize the advantageous features of a hydrogen-rich gas, whereby 'an enlarged' heat conduction area as well as an increased heat conduction rate are obtained.

3as reference number 94- denotes a catalyst holding plate in the form of a perforated plate with a number of narrow holes therein

- 37 -

«-Β« β β *

-Vh-

or a reticulated plate. If the catalyst is used for many years, it deteriorates it increases gradually and tends to be partially broken or pulverized. · Broken or powdered catalysts fall to the bottom of the double-walled catalyst-filled ones Pipes to accumulate here and thereby there is a risk of causing Difficulties such as preventing reformed gas from flowing smoothly, an interruption the same or the like. However, the arrangement prevents the porous catalyst bearing plate the occurrence of the difficulties described above * If the catalyst ' If the layer has to be overhauled "or replaced by a new one, it becomes the plate holding the inner tube 98 removed first and then the inner tube 88 by pulling down.

14 shows a diagram showing the temperature distribution over the double-walled, catalyst-filled Specifies pipes, where the temperature A in the fluidized layer, temperature B in the up. increasing current and temperature C in the descending stream as a function of the position in the catalyst-filled Tube to be shown.

V / ie from the diagram be seen that the reaction gas has a temperature 'of 85P ° C at the upper end portion of the catalyst-filled tube,' and it has a temperature of 700 ⁰ C at the outlet, which means that the catalyst-filled tubes as well as effective heat conductor to preheat the

- 38 -

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> * ft · «A ft ι * * ft«

»*« 9 «On«

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flowing fluids as well as for reforming at the same time serve the latter.

V / ie o ^{e (ies} · the catalyst-filled tubes is described above, arranged such that the lower end portion is fixedly attached, while the upper end is kept free. On the other hand, the arrangement 180 ° can be reversed ».erden, which means that each of the catalyst-filled pipes is suspended from the upper and lower end portions and is therefore kept free.

The fluidized © layer can either be under normal pressure, or under a special pressure-tight ·. Atmosphere.

It should also be mentioned that the invention not just on fuel reformers is limited, but also for heat exchangers of the liquid-layer type or the like Device applied can be.

Finally, a fuel reforming device is intended will be described according to the sixth embodiment of the invention with reference to Figure I5

In the drawing, reference numeral 121 denotes a housing for the fuel reforming device, which; Reference numeral 122 a fluidized layer, reference numeral 123 a cavity arranged above the fluidized layer 122, the; Reference numeral 124 an outer pipe which forms the double-walled catalyst-filled pipe and reference numeral 125 an inner pipe which

- 39

the same forms. Furthermore, that ... · · reference number 126 denotes a combustion gas outlet. '■' channel, .the reference number 12? a gas turbine, the reference number 128 an exhaust duct of the gas turbine, the reference number 129 a steam boiler (boiler) for exhaust gas heat recovery and the reference number 130 a chimney. The reference numeral 131 denotes a line pipe for conveying fuel based on hydrocarbons. The reference number 132 denotes a fuel pipe for the burners and the reference number 132 * denotes a multiplicity of burners which are constructed in the manner of a pipe socket. The reference numeral 133 denotes the "line pipe for 'raw gas that is to be reformed. The reference numeral 134 denotes a raw gas-steam mixer and the reference numeral 138 a delivery pipe for the mixture of raw gas and steam.

The reference numeral 135 denotes a feed water pipe for the steam heater, the reference mark a feed water pump and the B numeral 137 a steam pipe for the fuel to be reformed The reference number 139 denotes a Leitμng for reaction gas, the reference numeral 140 a heat-2 ^ meaustauscher, reference numeral 141 an inlet pipe for the C0 converter (shift converter) and the reference numeral 142 a CO converter. Farther Reference numeral 143 denotes a compressor (blower) for combustion air A, reference numeral 144 a combustion air duct, the reference number 145 a combustion air chamber and the reference number

- 40 -

--4Θ--

146 a generator. ·., · ·

Next, the operation of a fuel reformer device is described in greater detail above Design explained. '

The fuel, mixed with compressed air, which comes via the line 144, is burned with the aid of the burners 132 ', so that a fluidized heating layer 122 is formed in the pressure-tight state in which the material to be fluidized is forced to float. The fluidized layer 122 thus formed heats a large number of double-walled, catalyst-filled tubes, which are uniformly composed of both the outer and inner tubes 124 and 125, up to a predetermined elevated temperature, whereby the mixture of raw gas and steam is supplied is reformed via the pipe 138 while flowing through the catalyst layer filled in the double-walled pipes until reformed gas containing hydrogen and carbon dioxide as main components is generated. After the reforming reaction has ended, the reaction gas is withdrawn from the reforming system via the line. The reaction gas passes into a heat exchanger 140, in which it is cooled down to a previously determined temperature by heat exchange. It is then passed into the CO converter 142, in which carbon monoxide is _{reformed to hydrogen according to the chemical equation (GO + H 2} O - > GO ₂ + H ₂ ), so that

- 41 -

the hydrogen-rich gas H is obtained.

The exhaust gas generated in the fluidized layer after the combustion reaches the gas turbine 127 via the cavity located above the fluidized layer and via the combustion gas duct 126. The gas turbine 127 operates with the compressor (blower) 1-4-3 and the generator 146 connected so that the combustion air is compressed to a desired pressure and then conveyed to the fluidized layer via the combustion air duct 144 and the combustion air chamber 145.

Except for the operation of the compressor (blower) "143 is . an additional force to drive the generator

• 15 146 needed to be converted into electricity. After leaving the gas turbine, the exhaust gas flows into the exhaust gas heat recovery boiler 129 in the the / Värmeaustausch for heat recovery of the exhaust gas heat is effected. Thereafter, the exhaust gas is vented to the outside atmosphere via the vent 130. That Feed water for the exhaust gas heat recovery boiler 129 is introduced from the feed water pump 136, so that this is then evaporated in it. The steam generated in this way is mixed with fuel Kohgas-Lampf-Mixer 134 mixed.

When using the liquefied layers in the pressure-tight state, the following are required for the device Receive advantageous features.

(1) The speed of movement in the cavity can be; · reduced more than when operating under normal pressure will. Provided that the speed of movement in the cavity is the same as that during operation

. - 42 -

under normal pressure, the result is that the space required for the fluidized layer is reduced can be, so the entire device can be built in smaller dimensions.

(2) Assuming that the speed of movement in the cavity is optionally set to be low, the grain size of the material to be fluidized can be correspondingly reduced.

As a result, the number of catalyst-filled tubes wears little and even more so, entrainment into the cavity above the fluidized layer rarely takes place.

(3) Since the fluidization is effected in the pressure-tight state, the f-fluidized layer maintains a coefficient of thermal conductivity which is higher than that when operating under normal pressure.

(4) The thermal energy contained in the exhaust gas at an elevated temperature is recovered in the form of mechanical power that is used for ^driving both the gas turbine and the compressor (blower). In addition to this, an additional force is used to drive the shock generator. This makes it possible to build the boiler for exhaust gas / heat recovery to use the recovered heat in a smaller size.

(5) As the case of the fuel reformer represents the heaviest component, it can be built in "smaller dimensions, resulting in that transport and installation are carried out very easily. Furthermore, when the device

- 43 -

ILL

- 43 -.

composed of a large number of structural units, the transport can be carried out more easily with the aid of a trailer or a similar vehicle. - ■

(6) A fluidized layer has a constant temperature which is evenly distributed over the layer. Precise control of the operation of the fluidized layer ensures that the number of catalyst-filled tubes that are designed to exacerbate the temperature conditions in the fluidized layer, rain disturbances such as breaks, leak damage or the like is protected. Furthermore, other advantageous features of the fluidized layer, such as, for example, the operating characteristic under partial load, i.e. the excellent adaptability to changing loads at high speed and others, can be used to the satisfaction.

The invention has been described above in terms of several preferred embodiments. It should be understood, however, that it is not limited to only these, but various changes and modifications can be appropriately made without departing from the spirit and gist of the invention.

Claims (7)

Claims Device for reforming vein fuel, which is a Vy contains a large number of catalyst-filled pipes that support this are capable of being heated up to an elevated temperature by heating from the outside in order to thereby reforming fuel into gas, which has hydrogen as its main component, the fuel flowing through each of the catalyst-filled pipes, characterized in that the catalyst-filled tubes (4, 69, 82, 88, 124, 125) are arranged in a fluidized layer (24, 76, 81, 122). 2. Device for reforming fuel, which contains a large number of catalyst-filled tubes, which for this purpose are suitable up to an elevated temperature TELEX: TELEGRAM: PHONE: BANK ACCOUNT: CHECK ACCOUNT: 1-Β5Θ44 INVENTION BERUN BERLINERBANKAa P. MESSNER. BLN-W Inven d BERLIN 030/891 60 37 BERUN 31 404737-103 030/891 30 28 3695716000 Heating from the outside to thereby reform fuel into gas having hydrogen as a main component, the fuel flowing through each of the catalyst-filled tubes, characterized in that the catalyst-filled tubes (4,69,82, 88, 124, 125 ) are arranged in a fluidized layer (24, 76, 81, 122) and a heat exchanger (19, 72, 129) is attached at a previously determined location in which the heat exchange between the outflowing combustion gas and the inflowing combustion air is effected. 3. A device for reforming fuel, which contains a plurality of catalyst-filled tubes which are capable of being heated to an elevated temperature by heating from the outside, thereby reforming fuel into gas having hydrogen as a main component, the Fuel flows through each of the catalyst-filled tubes, characterized in that the catalyst- _{filled tubes (4,69 f} 82,88,124,125) are arranged in a fluidized layer (24,76,81,122) and a recirculation passage (circulating air passage) (30,32) is provided, by means of which part of the combustion gas which has been drawn off from the flue duct (28) is forced to recirculate in a pressure-tight state. 4. Device for reforming fuel according to claim 1, characterized in that the catalyst-filled tubes (4,69,82,88,124,125) in a fluidized layer (24,76,81,122), which aue composed of non-combustible material to be fluidized, arranged and a plurality of Pipe burners (5,60,92,132 ') above the sub-floor the fluidized layer (24,76,81,122) is arranged. 5. Device for reforming fuel according to Claim 1, characterized in that each of the catalyst-filled tubes (4,69,82,88,124, 125) is designed in the form of a double-walled tube. 6. Device for reforming fuel according to claim 2, characterized in that that each of the double-walled, catalyst-filled tubes has an annular space between the outer Tube (82,124) and the inner tube (88,125) is stamped to fill the catalyst therein and it also contains a catalyst-carrying porous plate (94) which is fixed to the outer wall surface of the inner tube and a plurality of baffles (95) are attached to its upper end to change the direction of grass flow and to promote heat conduction and a thermal tape (96) is disposed within the inner tube (88). 7. Device for reforming fuel according to claim 1, characterized in that that the fluidized layer (24,76,81,122) is constructed in its type so that it is in the pressure-tight state works and that a gas turbine is installed at a predetermined location, from the combustion gas is driven.