BURNER FOR CARRYING OUT PARTIAL OXIDATION

Description

[0001] The invention relates to a burner for carrying out a partial oxidation with at least two channels through which a fluid can flow in order to carry out the partial oxidation. Background of the invention

[0002] During partial oxidation, a hydrocarbon-containing fuel, e.g. natural gas, petroleum gas or heating gas, can be partially combusted with an oxidant, for example in the form of an oxygen-containing gas, e.g. oxygen or air or a mixture thereof, in a substoichiometric mixing ratio to produce a synthesis gas. The synthesis gas produced is a mixture of carbon monoxide and hydrogen, which can be used, for example, in fuel cells. Furthermore, a moderator, e.g. water vapor or carbon dioxide, can be added to the fuel and / or the oxidant to regulate the ratio between hydrogen and carbon monoxide in the produced synthesis gas or, for safety reasons, to automatically purge the burner in the event of an error or malfunction.

[0003] Burners for partial oxidation can be designed as multi-channel burners with several concentric channels, through each of which a fluid can flow. Such a burner usually has a central channel and one or more annular channels surrounding this central channel. Furthermore, a cooling channel for a cooling fluid, e.g., water, can be provided in one or more walls of the burner to cool the burner.

[0004] At the front end of the burner, viewed in the direction of fluid flow, a burner tip can be provided, which can, for example, be truncated conically shaped. In this burner tip, the outer annular channels can, for example, run toward the central channel at a predetermined inclination or outlet angle. In this way, the fluids guided through the annular channels can each run at a predetermined inclination or outlet angle.

[0005] Outlet angle relative to a fluid flow of the central core from the burner tip.

[0006] For example, US 4 888 031 A describes a process for partial oxidation using a concentric burner arrangement consisting of four concentric ring channels and one central channel.

[0007] US Pat. No. 3,255,966 A, for example, discloses a burner for partial oxidation with an inner channel and an annular outer channel concentric with the inner channel. Cooling channels for a cooling fluid for cooling the burner are provided in an outer wall of the burner.

[0008] US Pat. No. 4,865,542 A, for example, shows a burner for partial oxidation with an inner channel and two concentric, annular channels. A supply line and an outlet line for a cooling fluid are provided in one wall of the burner. The supply and outlet lines are connected via a spiral channel in a tip of the burner.

[0009] US 3,255,966 discloses a burner according to the preamble of the first claim. Disclosure of the invention

[0010] Against this background, a burner for carrying out a partial oxidation with the features of patent claim 1 is proposed. Advantageous embodiments are the subject of the subclaims and the following description.

[0011] The burner is intended for carrying out a partial oxidation of fluids, in particular a hydrocarbon-containing fuel, e.g., natural gas, petroleum gas, or fuel gas, and an oxidizing agent, in particular in the form of an oxygen-containing gas, e.g., oxygen or air, or a mixture thereof. The burner has at least two channels, through each of which a fluid can flow to carry out the partial oxidation. In particular, the burner has a central channel and at least one annular channel surrounding this central channel. The individual channels can expediently be connected to a corresponding fluid supply.

[0012] An insulation element is arranged on an inner surface or on an inner side of a wall of at least one of the at least two channels, at least along part of an axial length of this at least one channel. The respective channel is expediently delimited radially outwards or in the radial direction outwards by this wall. This wall is thus to be understood in particular as a radial wall or boundary wall of the respective channel. The inner surface or inner side is to be understood in particular as an inner surface of this wall in the radial direction. This inner surface or inner wall surface or inner wall side is thus expediently to be understood as the (top) surface of the wall facing the fluid flow of the respective channel, in contrast to the outer (top) surface or outer wall surface or outer wall side of the wall facing away from the fluid flow of the respective channel.The insulation element, which is arranged on this inner surface, is thus in direct contact with the fluid flowing through the respective channel. The insulation element expediently surrounds the corresponding channel in a ring-shaped manner.

[0013] This insulation element is provided in the respective channel in particular to thermally insulate a fluid flowing through the channel, expediently from parts of the burner that are further outward, viewed in the radial direction. In particular, this fluid can be insulated, shielded, or protected from thermal influences, for example from heat sources or heat sinks, in these further outward burner parts. Conversely, these further outward burner parts, and in particular a fluid flowing through these parts, can be insulated, shielded, or protected from thermal influences of the fluid within the channel provided with the insulation element. In particular, it can thus be achieved that the fluid flowing in the corresponding channel provided with the insulation element is heated or cooled less severely by external temperature influences.Conversely, it can be advantageously achieved that a fluid flowing in the burner parts located further out is heated or cooled to a lesser extent by the fluid flowing in the insulated channel.

[0014] In particular, the insulation element can reduce thermal effects such as heat exchange within the burner. For example, a desired or predetermined temperature difference between the outer burner parts and the fluid in the insulated channel can be maintained, or at least a reduction in this temperature difference due to heat exchange can be reduced. Thermal loads within the burner, in particular thermal stresses or mechanical stresses due to thermal loads, can be advantageously avoided or at least reduced.

[0015] The present invention provides a particularly effective way to thermally insulate components or fluids within the burner. In particular, this increases the effectiveness of the burner. Stresses within the burner can be reduced. Defects and repairs can be avoided. Maintenance intervals can be extended. Costs can be reduced. The service life of the burner and its individual components can be increased. By arranging the insulation element on the inner wall surface, i.e., within the respective channel, particularly space-saving, flexible, and effective insulation can be achieved. For example, a burner can be retrofitted with appropriate insulation elements in a structurally simple and low-cost manner.

[0016] According to a particularly preferred embodiment, the burner further comprises at least one cooling channel, through each of which a cooling fluid can flow to cool the burner. Advantageously, the at least one cooling channel surrounds the at least two channels in an annular manner, particularly when viewed in the radial direction. In particular, this at least one cooling channel is provided in a wall of the burner and, particularly when viewed in the radial direction, is arranged outside the at least two channels or radially adjacent to the at least two channels. Advantageously, the at least one cooling channel can be connected to a cooling fluid inlet and a cooling fluid outlet in order to advantageously allow cooling fluid to flow continuously from the cooling fluid inlet through the at least one cooling channel to the cooling fluid outlet to cool the burner. For example, water can be used as the cooling fluid.

[0017] Particularly advantageously, the insulation element is arranged on the inner wall of the channel of the at least two channels adjacent to the at least one cooling channel, at least along part of an axial length of this adjacent channel. The insulated channel is particularly expediently arranged directly adjacent to the at least one cooling channel, viewed in the radial direction. Particularly expediently, the at least one cooling channel can directly surround this insulated channel in a ring-shaped manner. For example, the channel provided with the insulation element can be an outer channel of the at least two channels, viewed in the radial direction. For example, the cooling channel can be arranged in the wall of the correspondingly insulated channel. Furthermore, the wall of the insulated channel can, for example, correspond to the outer wall of the burner.

[0018] The insulation element can be used to particularly effectively prevent or at least reduce heat transfer from the fluid in the insulated channel to the cooling fluid. This can thus be advantageously prevented or at least reduced from heating the cooling fluid due to the temperature of the fluid flowing through the insulated channel. The burner can thus be cooled more effectively. Furthermore, the amount of cooling fluid required for cooling can be reduced.

[0019] Due to a temperature difference between the temperature of the cooling fluid in the cooling channel and the temperature of the fluid in the immediately adjacent channel, significant thermal or mechanical stresses could occur in the wall of this adjacent channel. By arranging the insulation element on the inner surface of this adjacent channel, such stresses in the wall can be significantly reduced. The service life of the burner can thus be increased.

[0020] The individual fluids in the burner channels can, for example, contain water vapor. Water vapor can be expediently added to the fuel, for example, to regulate the ratio between hydrogen and carbon monoxide in the generated synthesis gas, or for safety reasons, to automatically purge the burner in the event of a fault or malfunction. A high partial pressure could cause the water vapor to condense on a cold wall of an adjacent cooling channel, creating droplets that could damage the burner tip through erosion. By arranging the insulation element on the inner wall surface of the channel adjacent to the cooling channel, such condensation of water vapor can be prevented. This prevents damage to the burner and increases its service life.

[0021] According to a preferred embodiment, the at least one channel is configured to be connected to a fluid supply for supplying a preheated fluid and / or a fuel, in particular a preheated fuel. For example, the fluid, in particular the fuel, can be preheated to temperatures of up to 800°C. The insulation element can expediently prevent or at least reduce the cooling of this preheated fluid due to a temperature difference with an adjacent burner part located further outwards. The efficiency of the preheating can thus be increased and, in particular, the amount of energy required for preheating can be reduced. Furthermore, thermal expansion of the channel wall due to the high temperatures of the fluid can be compensated for or prevented or at least reduced.

[0022] If, particularly advantageously, the at least one cooling channel is provided adjacent to the channel insulated with the insulation element, heating of the cooling fluid due to the higher temperature of the preheated fluid can be advantageously prevented or at least reduced. Conversely, cooling of the preheated fluid due to the low temperature of the cooling fluid can be particularly advantageously reduced or at least slowed down. For example, the temperature of the cooling fluid can be limited to approximately 60°C, whereas the preheated fluid is heated, for example, to temperatures of up to approximately 800°C. The insulation element advantageously prevents or reduces stresses in the wall of the corresponding channel due to this high temperature difference of several hundred degrees.

[0023] Preferably, the insulation element is removable or replaceable from the at least one channel. The insulation element can be removed and reinserted, or replaced with a new insulation element, in particular in a structurally simple and low-cost manner in the event of damage or for maintenance, cleaning, or repair work. Therefore, the insulation element is not rigidly connected to the wall of the at least one channel. The insulation element can expediently be inserted into the corresponding channel. In particular, the insulation element can be axially displaceable within the corresponding channel. Thus, the axial position of the insulation element relative to the channel or relative to the burner can be changed and adjusted as needed.

[0024] Preferably, the insulation element is arranged in the at least one channel at least from a rear end of the at least one channel, viewed in the direction of flow, to a position that is at a predeterminable or predetermined axial distance from a front end of the at least one channel, viewed in the direction of flow. The front end corresponds in particular to an end of the burner tip, at which the individual fluids are emitted or discharged from the burner. In particular, this axial position, up to which the insulation element extends, can be determined by design or, for example, can be predetermined depending on thermal, thermodynamic, or fluid-dynamic conditions within the corresponding channel.

[0025] Alternatively or additionally, the insulation element is preferably arranged in the at least one channel at least from a fluid connection for supplying a fluid into the at least one channel up to a position that is at a predeterminable or predetermined axial distance from a front end of the at least one channel, viewed in the direction of flow. In particular, the fluid within the corresponding channel can thus be insulated from the fluid connection, i.e., expediently from the axial position at which the fluid is fed into the channel.

[0026] The insulation element preferably extends in the at least one channel in the axial direction up to a burner tip, in particular up to a start of the burner tip viewed in the direction of flow. The position explained above at the predeterminable axial distance from the front end of the channel, up to which the insulation element is arranged, expediently corresponds to the start of the burner tip. The burner tip can, for example, be truncated cone-shaped. In the burner tip, the annular channels can particularly expediently run towards the central channel at a predetermined inclination or outlet angle. In particular, the insulation element can be arranged in an axial region of the respective channel in which this channel or its wall runs parallel or at least substantially parallel to a longitudinal axis of the burner or to a longitudinal axis of the central channel.The insulation element expediently extends within the respective channel up to the position from which the channel or its wall bends and runs towards the central channel at the corresponding angle of inclination or outlet.

[0027] The insulation element is preferably designed as a tube or as a tubular element. In particular, this enables the insulation element to be easily inserted into and removed from the respective channel, which is expediently also formed by a tube or a tubular element. A shape of the insulation element and a shape of the respective channel, or a shape of the channel along the respective part in which the insulation element is arranged, particularly expediently correspond to one another or correspond to one another at least substantially. Particularly expediently, a shape of an outer surface of a wall of the insulation element corresponds at least substantially to a shape of the inner surface of the wall of the channel. The insulation element can therefore expediently fit precisely orare inserted into the channel in a form-fitting manner, so that no fixed connection is required and the insulation element can be easily removed again.

[0028] The insulation element is made of a thermally insulating material. In particular, the thermally insulating material can withstand the high temperatures that the fluid within the corresponding channel may experience, and furthermore, in particular, large temperature differences between the temperature of the fluid within the channel and a temperature outside the channel, expediently a temperature of a cooling fluid outside the channel.

[0029] The insulation element is made of mica. Mica is a mineral consisting primarily of silicon (Si), aluminum (Al), magnesium (Mg), and potassium (K). The structure is formed by many layers of sheet-like framework layers consisting of Si, Al (or Mg) oxides and K ion layers. Because mica is a natural, inorganic mineral, it possesses very good heat-resistant properties and is particularly advantageous as a material for the insulation element. For example, the insulation element can be made of muscovite or phlogopite, or of a material containing muscovite and / or phlogopite. Muscovite, KAl2(Si3Al)O10(OH)2, for example, can withstand temperatures of up to 800°C, while phlogopite, KMg3(Si3Al)O10(OH)2, for example, can withstand temperatures of up to 1000°C. Furthermore, the mica material can be conveniently coated orbe laminated, for example with a high-temperature resistant silicone.

[0030] Preferably, the thickness of a wall of the insulation element lies in a range between 25% and 175% of the thickness of the wall of the at least one channel, more preferably in a range between 50% and 150% of the thickness of the wall of the at least one channel, more preferably in a range between 75% and 125% of the thickness of the wall of the at least one channel. Thickness is understood to mean, in particular, a dimension of the respective wall in the radial direction.

[0031] Further advantages and embodiments of the invention will become apparent from the description and the accompanying drawings.

[0032] The invention is illustrated schematically in the drawing using exemplary embodiments and is described below with reference to the drawing. Short description of the drawings

[0033] Figure 1shows a preferred embodiment of a burner according to the invention in a schematic sectional view. Embodiment(s) of the invention

[0034] Figure 1 shows in a schematic sectional view a preferred embodiment of a burner 100 according to the invention for carrying out a partial oxidation.

[0035] The burner 100 is designed as a multi-channel burner and comprises a central channel 110 and an annular channel 120 surrounding this central channel 110. A fluid can flow through each of the channels 110, 120 to carry out the partial oxidation. For this purpose, the two channels 110, 120 can each be connected to a corresponding fluid supply via a corresponding fluid inlet or fluid connection 111, 121, so that a corresponding fluid can flow from the fluid inlet 111 or 121 to a fluid outlet 112 or 122 in a burner tip 101. At an end of the central or annular channel 110 or 120 opposite the fluid outlet 112 or 122, a closable flange connection 115, 125 is provided, for example.

[0036] The respective fluids are emitted from the burner through these fluid outlets 112 and 122 to generate a synthesis gas in the form of a mixture of carbon monoxide and hydrogen during partial oxidation. In the frustoconical burner tip 101, the annular channel 120 extends toward the central channel 110 at a predetermined inclination or outlet angle, so that the respective fluid from the fluid outlet 122 is emitted at this corresponding inclination or outlet angle relative to the fluid flow from the fluid outlet 112 of the central channel 110.

[0037] For example, an oxidizing agent in the form of an oxygen-containing gas, e.g. oxygen or air or an air-oxygen mixture, can be passed through the central channel 110. For example, a preheated, hydrocarbon-containing fuel, e.g. natural gas, can be passed through the annular channel 120. In particular, the fuel can be preheated to temperatures of up to 800°C. For this purpose, the central channel 110 can be connected via its fluid inlet or fluid connection 111, for example, to an oxidizing agent supply, and the annular channel 120 can be connected via the fluid inlet or fluid connection 121, for example, to a fuel supply. Furthermore, the supplied fuel and / or the supplied oxygen-containing gas can each contain a moderator, e.g. in the form of water vapor, in order to regulate a ratio between hydrogen and carbon monoxide in the synthesis gas produced and / or in order to prevent a malfunction orIn the event of a fault, the burner 100 is automatically flushed.

[0038] Furthermore, a cooling channel 130 for a coolant for cooling the burner 100 is provided in a wall 102 of the burner 100. A cooling fluid inlet 131 can be connected to a coolant supply, so that a cooling fluid, e.g., water, can continuously flow from the cooling fluid inlet 131 through the cooling channel 130 to a cooling fluid outlet 132. For example, the maximum temperature of the cooling fluid can be 60°C.

[0039] To prevent or at least reduce heat exchange between the preheated fuel within the annular channel 120 and the cooling fluid within the cooling channel 130, an insulating element 140 is arranged on an inner surface 123 of a wall 102 of the annular channel 120. For example, this wall 102 of the annular channel 120 may correspond to the wall 102 of the burner 100 in which the cooling channel 130 is provided.

[0040] The insulation element 140 allows the preheated fuel within the annular channel 120 to be thermally insulated, so that the fuel is not cooled, or at least only slightly cooled, by the cooling fluid in the cooling channel 130, and conversely, the cooling fluid is not heated, or at least only slightly heated, by the fuel. Furthermore, thermal loads and mechanical stresses within the burner wall 102 due to the temperature difference between the fuel and the cooling fluid can be avoided or at least reduced. The service life of the burner 100 can thus be increased.

[0041] If the supplied fuel contains water vapor, the water vapor could condense on the inner wall surface 123 of the annular channel 120 due to its high partial pressure, creating droplets that could damage the burner tip 101 through erosion. The insulation element 140 arranged on this inner surface 123 can prevent such condensation of water vapor and corresponding damage to the burner 100, and the service life of the burner 100 can be increased.

[0042] This insulation element 140 is arranged at least along part of an axial length of the annular channel 120. For example, the insulation element 140 can extend at least from the fluid inlet 121 to a position 103 that is a predeterminable axial distance from a front end of the annular channel 120, viewed in the flow direction. For example, this position 103 can correspond to the beginning of the burner tip 101.

[0043] The insulation element 140 is tubular, for example. In particular, a shape of the insulation element 140 or a shape of the outer (top) surface of the insulation element 140, viewed in the radial direction, corresponds, at least substantially, to a shape of the annular channel 120 or the inner (top) surface 123 of the wall 102 of the annular channel 120. In particular, the insulation element 140 can thus be axially inserted into the annular channel 120 and can be flexibly removed from the channel 120 again, for example, through the flange connection 125.

[0044] The insulation element 140 is made of a mica material, for example a material containing muscovite and / or phlogopite.

[0045] Furthermore, it is also possible to alternatively or additionally arrange a corresponding insulation element on the inner surface of the wall of the central channel 110. It is understood that the burner can also have a plurality of annular channels for supplying fluids, which can concentrically surround the central channel 110 and the annular channel 120. For example, several or all of these annular channels can each have a corresponding insulation element arranged on the inner wall surface of the respective channel. Furthermore, it is also conceivable, for example, that an insulation element is arranged only in the radially outermost annular channel, which is directly adjacent to the cooling channel in the radial direction. List of reference symbols

[0046] 100 Partial oxidation burner 101 Burner tip 102 Burner wall 103 Beginning of the burner tip 110 Central channel 111 Fluid inlet 112 Fluid outlet 115 Flange connection 120 Annular channel 121 Fluid inlet 122 Fluid outlet 123 Inner surface of the wall of the annular channel 125 Flange connection 130 Cooling channel 131 Cooling fluid inlet 132 Cooling fluid outlet 140 Insulation element

Claims

1. A burner (100) for implementing partial oxidation, having at least two channels (110, 120), which are in particular designed as one central channel (110) and at least one annular channel (120) surrounding the central channel, through each of which a fluid can flow to implement the partial oxidation, an insulation element (140) being arranged on an inner face (123) of a wall (102) of at least one channel (120) of the at least two channels (110, 120) at least along part of an axial length of this at least one channel (140), characterized in that the insulation element (140) is made of a mica material.

2. The burner (100) according to claim 1, further having at least one cooling channel (130), through each of which a cooling fluid (130) for cooling the burner can flow, wherein the at least one cooling channel (130) annularly surrounds the at least two channels (110, 120), wherein the insulation element (140) is arranged on the inner face (123) of the wall (102) of the channel (120) of the at least two channels (110, 120) adjacent to the at least one cooling channel (130), at least along part of an axial length of this adjacent channel (120).

3. The burner (100) according to claim 1 or 2, wherein the at least one channel (120) is configured to be connected to a fluid supply for supplying a preheated fluid and / or a fuel, in particular a preheated fuel.

4. The burner (100) according to any of the preceding claims, wherein the insulation element (140) is removable from the at least one channel (120).

5. The burner (100) according to any of the preceding claims, wherein the insulation element (140) is arranged in the at least one channel (120) at least from a rear end of the at least one channel (120) as viewed in the flow direction to a position (103) which is at a predeterminable axial distance from a front end (122) of the at least one channel (120) as viewed in the flow direction, and / or wherein the insulation element (140) is arranged in the at least one channel (120) at least from a fluid port (121) for supplying a fluid into the at least one channel (120) to a position (103) which is at a predeterminable axial distance from a front end (122) of the at least one channel (120) as viewed in the flow direction.

6. The burner (100) according to any of the preceding claims, wherein the insulation element (140) extends in the at least one channel (120) in the axial direction up to a burner tip (101).

7. The burner (100) according to any of the preceding claims, wherein the insulation element (140) is designed as a tube or tubular element.

8. The burner (100) according to any of the preceding claims, wherein the insulation element (140) is made of a thermally insulating material.

9. The burner (100) according to any of the preceding claims, wherein a thickness of a wall of the insulation element (140) is in a range of between 25% and 175% of a thickness of the wall (102) of the at least one channel (120), in particular in a range of between 50% and 150% of the thickness of the wall (102) of the at least one channel (120), in particular in a range of between 75% and 125% of the thickness of the wall (102) of the at least one channel (120).