• 专利附录
  • 专利说明
  • 权利要求
  • 类似技术
  • 同族专利
  • 引用文献
  • 法律状态
  • 优先权
    • 专利摘要:
    PROCESS AND APPARATUS FOR ENDOTHERMIC REACTIONS. The present invention relates to a furnace for carrying out an endothermic process, comprising tubes (2), which contain a catalyst to convert a gaseous feed, said tubes (2) being positioned inside the furnace (1), internal burners (3a) mounted in a furnace roof (1b) between the tubes (2) and external burners (3b) mounted in the furnace roof (1b) between the tubes (2) and a furnace wall (1a). The external burners (3b) are positioned close to the furnace wall (1a), and configured to operate with 45 - 60% of the power of the internal burners (3a) and with an input speed between 90 and 110% of the input speed of the internal burners (3a).
    公开号:BR112015004134B1
    申请号:R112015004134-5
    申请日:2013-08-14
    公开日:2021-05-04
    发明作者:Julien Cances；Frederic Camy-Peyret；Bernard Labegorre
    申请人:L'air Liquide - Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude；
    IPC主号:
    专利说明:

    [001] The present invention relates to the configuration of furnaces with high combustion to reform steam methane (SMR) and other endothermic reactions in reactors with external combustion.
    [002] The SMR process is mainly based on the reaction of light hydrocarbons, such as methane, which provides a mixture of hydrogen (H2) and carbon monoxide (CO), in the presence of water vapor. The reaction is endothermic and slow and requires additional heat input as well as a catalyst to occur. The SMR reactor usually comprises several tubes placed in an oven, said tubes being filled with catalyst pellets and fed with the process gas mixture of methane and steam.
    [003] Several types of oven configurations are found throughout the industry. High combustion technology is one of the most recommended configurations and is proposed by several technology providers. Burnout furnaces are typically made of a refractory lined furnace containing several rows of tubes that contain catalyst. Ceiling burners are placed in rows between the rows of tubes and the products of combustion from the burners are normally blown vertically downward, so that the rows of tubes face the flames on top of them. A flue gas exhaust manifold is normally provided at the floor level of the furnace.
    [004] The main objective of the furnace configuration, often also called the furnace configuration, is to maximize the heat transferred from the burner flames to the tubes, while respecting a maximum operating temperature limitation, which is a function of the mechanical load of the tube (mainly feed gas pressure), the mechanical properties of the alloys used for the pipes, and the desired life of the pipes. In fact, any intensification of the heat transferred to the tubes has a direct positive impact, either on furnace productivity or the reduced furnace size, which is valuable in terms of capital expenditure. However, increasing the amount of heat usually implies higher temperature levels of the tube coating, which reduce tube life or require stronger alloys, which are much more expensive.
    [005] The temperature profiles of catalyst tubes are therefore a critical element of furnace configuration and operation, at the focal point of the compromise between performance and durability. Typical vertical profiles for tube heat flux and temperature are drawn in the Figure. 2 on a circumferential mean. The heat flux profile clearly highlights that the feed inlet (top) portion of the tube is the preferred zone for heat transfer. In fact, several factors favor the maximization of heat flow:
    [006] • Neighborhood of the burners and power entry point, implying a maximum temperature difference between the load (pipes) and the heat release source (burners)
    [007] • Higher reaction rates and therefore heat drop, which pulls tube temperatures down.
    [008] This highlights the superiority of the Alto Combustion model, compared to others, with respect to heat transfer efficiency.
    [009] The denser the heat flux and temperature profile at the top of the tube, the higher the amount of heat for the tube at the same calculated temperature (strength to creep), and therefore the higher the capacity of process gas flow amount per pipe at the same conversion amount. The effective overhead combustion design to increase heat transfer at the top of the kiln is limited to the ability of gaseous flames produced by conventional burners used in kilns to transfer chemical energy to the radiation tubes of hot gases. In fact, several phenomena limit the ability of conventional bottom combustion burners:
    [0010] • High levels of nitrogen oxide (NOx) penalize the selection of short flame burners for environmental reasons, while a typical way to reduce thermal NOx emissions is to dilute the flame with flared gases or adjust fuel injections, so that the maximum flame temperature is reduced to below 1000°C. As a result, the flame's ability to transfer heat to the top of the furnace and thus the heat supplied to the reaction is reduced. This limitation is a typical trade-off between longer, cooler flames and shorter, less efficient flames for NOx.
    [0011] • The physics of radiation heat transfer between gaseous media and walls is intrinsically less efficient than that between wall surfaces or different temperatures. The characteristically sized 1m volume of hot gases typically has a net emission far below a high emission solid surface heated to the same temperature.
    [0012] Furthermore, in overhead combustion reformers, the heat necessary for the endothermic reaction to occur is provided by burners located between the tubes. Additional burners on the side of the kiln along the walls of the kiln are heating just a row of tubes on one side and the refractory wall on the other side. Burners in the center of the furnace are heating two rows of tubes on either side of the row of burners. Therefore, the required wattage of the side burners is less (~52%, including heat losses in the side wall) than that in the center of the furnace. Reducing the power injected into the rows of side burners, while keeping the stoichiometry constant, implies reducing the amounts of air and fuel flow.
    [0013] The fluid mechanism and jet theory define the typical flow arrangement within an overhead furnace, meaning the aspiration of jets of hot flue gases from side burners towards the center of the middle of the furnace. The jet flame drags part of the surrounding flue gas, creating a depression and, consequently, a flue gas recirculation. Therefore, the burners located along the walls are subjected to less recirculation (ie depression) on the wall side than on the furnace side, due to the presence of the next row of burners. If lower power or flow amounts along the sidewalls lead to a lower velocity, this reinforces the bending effect of the side flames towards the center, due to the weaker thrust of the side jets, as illustrated in the Figure. 3.
    [0014] In US 2007/0099141 A1 a method and an oven are proposed to generate flames aligned in an oven, whereby an oxidant is introduced into a plurality of oxidant conduits. Each of the oxidant conduits has an outlet in fluid communication with an oven interior near a first interior end of the oven. The first inner end of the oven has a horizontally projected area. The oxidant conduit outlets define a combined turbulence-free jet area that projects horizontally at 30% of the average distance from the first interior end of the furnace to a second interior end of the predicted furnace opposite the first interior end.
    [0015] Document US 2007/0128091 describes a furnace chamber surrounded by a circumferential furnace wall, in which a plurality of burners are arranged essentially in a plane, with the burner outlet direction facing downwards and a plurality of reaction tubes, arranged essentially vertically and parallel to one another, the reaction tubes being heated from the outside by means of combustion burners. The aim is to improve heat distribution and all heat transfer. This is achieved by arranging at least the external burners in the region of the furnace wall with a burner outlet direction, which is inclined with respect to the vertical, away from the center of the furnace.
    [0016] «The document EP 2 369 229 A2 describes a reformer and a method for operating that reformer, including the combustion of a fuel in a combustion region of a reformer with superior or inferior combustion, wherein at least one of the burners is a burner attached to the wall, forming a non-uniform injection. The non-uniform injection properties generate a heat profile that provides a first heat density proximal to a wall and a second heat density distal to the wall, the second heat density being greater than the first heat density. Non-uniform injection properties are formed by selecting an angle of one or more injectors, an amount of flow from one or more injectors, an amount and/or location of oxidizer injectors, an amount and/or location of fuel injectors, and combinations thereof.
    [0017] «The article "Fluegas flow patterns in top-fired steam reforming furnaces" by W. Cotton, published in 2003., by Johnson Matthey, teaches that reformers, which comprise external burners, with a combustion with a quantity of 70% compared to internal burners and an outer race between the tubes and the side of the furnace that is 70% the width of the internal races between two rows of tubes reduces the recirculation problem. According to the article, it is also possible to operate with an estimated 100% of external burners with combustion inside an external race with the same width as the internal races, without any curvature of the flames towards the center of the furnace.
    [0018] All the proposed solutions have in common the fact that they do not allow a furnace configuration, which supplies external burners only with the amount of power needed. As shown, for example, in the aforementioned article "Fluegas flow patterns in top-fired steam reforming furnaces", the amount of burner power is not reduced to the calculated value of about 52%. from the flame to the center of the furnace, but they do not prevent overheating of the tubes containing catalyst, located close to the furnace walls. This overheating leads to unwanted side reactions and irreversible catalyst damage.
    [0019] Therefore, it is the objective of the present invention to propose an oven and a method to operate this oven, which avoids the bending effect of the side flames to the center, as well as the problem of overheating of the tubes near the walls of the oven.
    [0020] This task is performed by the characteristics of the present claim 1. The furnace to carry out an endothermic process comprises several tubes that contain tubes, which are arranged inside the furnace, typically in rows. Within these catalyst tubes, a gaseous feed (reactant) is converted into an absorbing reaction energy by the environment in the form of heat. This heat is provided by several burners, which are positioned on the upper side of the oven. Parts of the burners are the so-called "inner burners" and are positioned between the rows of tubes, while the so-called "outer burners" are arranged between the outermost tubes and the furnace wall. Burner outlet direction is facing downwards. The catalyst tubes are arranged essentially vertically and parallel to each other, with the feed flowing through the tubes from top to bottom.
    [0021] To prevent flame bending and tube overheating, three modifications to the current configuration are proposed:
    [0022] *The external or side burners are positioned close to the wall, so that their flames are glued to the refractory part. This prevents the flames from bending towards the center of the furnace, due to the so-called "jet wall" effect, which allows the flame to run out of the wall. Close to the wall, in the sense of the present invention, means that the current emitted from the burner nozzle is running directly along the wall. The burner is positioned as close as possible to the wall, even touching it. Preferably this means that the distance from the central axis of the burner to the furnace wall is less than 25%, preferably 10%, particularly preferably 5%, most notably preferably 2% of the distance between the tubes plus external and the oven wall. In most cases the side burners are not circular but of a flat rectangular shape.
    [0023] • The power of the lateral or external burners is adjusted to a value between 45 and 60%, preferably 50 to 55%, of the power of the internal burners. This prevents the tubes in the second row of tubes from overheating as explained above. Power is adjusted by the amount of fuel burned.
    [0024] • «the external burners are dimensioned in such a way that their velocity in the jet inlet is essentially the same as in the internal burners. Deviations from max. 10%, preferably 5%, is possible. This allows the flow arrangement to be smoother and the streamlines straighter down. The burner feed inlet speed is adjusted by the total volume flow through the burner nozzle.
    [0025] In a preferred embodiment of the invention, the tubes are arranged in rows. According to the invention, a row is an arrangement of at least two, preferably at least three, burners in a straight line or an arrangement of burners with the same distance to the center of the furnace (such as rings around the center of a circle).
    [0026] The ratio of the distance between the side wall of the furnace and the first row of tubes to the empty space between the two subsequent rows of tubes is set to the same value as the ratio between the power of the external and internal burners. This allows a constant average speed to be maintained over the furnace. This should prevent flow disturbance due to differential speeds from different regions of the furnace.
    [0027] Furthermore, the inventive idea to generate a homogeneous temperature profile for the furnace is even better achieved if a so-called "solid surface with high emissivity" is used. For this purpose, at least parts of the walls are provided with a high temperature resistance, solid surface with high emissivity. The radiating surfaces are arranged in such a way that they extract a lot of heat from the flames through radiative and convective exchange to have a higher surface temperature and in such a way that they emit a high radiation flux back towards the upper part of the tubes, said tubes being at relatively low temperatures compared to the radiating surfaces.
    [0028] High emissivity refractory bricks, or thin plates or coated layer are arranged on the surface of the furnace roof and the top of the side walls, and the high emissivity is both due to the material's intrinsic properties, for example, using carbide plates of silicon, or by surface treatment or texturing, for example using ceramic foam sheets, preferably made of aluminum oxide or silicon oxide.
    [0029] Particularly good results are obtained if at least a part of the burners are called "jet flame burners". So-called "jet flames" are characterized by an initial flame velocity profile similar to a fully developed tube stream. The flame brush is primarily confined within the jet's mixing layer. The flames are too oblique for the incident current and appear thinner and taller.
    [0030] Also the configuration of at least some of the burners as so-called burners with "high swirl ball flame technology" leads to a very homogeneous temperature profile over the furnace. High eddy promotes the formation of a recirculation zone and is the essential mechanism for flame stabilization. Turbulent currents can be produced either by tangential jet injections or by vane swirl devices. The flame is anchored by the hot products enclosed within the recirculation zone. The amount of eddy expressed in terms of a eddy number determines the size and intensity of the recirculation zone in most flame properties.
    [0031] The implementation of the flame within a closed space of porous radiator casing leads to a more homogeneous temperature profile of the flame itself. The radiator casing is made of high temperature resistant material such as porous ceramic foam with high emissivity (silicon carbide, aluminum oxide and silicon oxide). The use of radiant burners makes it possible to configure the furnace with optimized shims from tube to burner tube, which minimizes inhomogeneities in the circumferential flow. The most interesting shims are a square or hexahedral configuration of the burner in relation to the catalyst tubes.
    [0032] The square block is advantageous for the homogeneity of the heat flow and allows for a simpler configuration of the distribution tube, for the distribution of fluids (combustion air, fuel and supply); however, it needs a higher burner density per tube.
    [0033] Hexahedral shim is great from the point of view of heat flow distribution and limitation of numbers of burners, but requires a slight additional complexity in configuring fluid distribution and collecting systems. The length of the radiating envelope must be adapted based on the pavement and tube diameter, advantageously between 10 and 40% of the tube length, optimally between 20 and 33% of the tube length.
    [0034] The preferred configuration of the furnace roof is such that the surfaces of high temperature, high emissivity, have their respective normal directed towards the tubes. The corresponding emitter surfaces can advantageously be considered either protruding in a convex shape into the combustion chamber or, conversely, being set back in a concave shape. High emissivity refractory sheets can be placed in the region heated by the flame. For the convex shape, the simplest embodiment is based on wall burners with jet flames directed downwards around the convex bulge with flames directed downwards. A more complex configuration provides for the flames to burn upward from the tip end of the convex bulge, to increase the irradiation area covered by the flames and thus transfer efficiency to the tubes.
    [0035] The invention also covers a process for operating a furnace as described above. This process includes the features of claim 11. A gaseous reactant is fed through tubes containing catalyst to carry out an endothermic process. The catalyst tubes are positioned inside the furnace and are heated by internal burners placed at the top of the furnace, between the tubes, or by external burners placed at the top of the furnace, between the outermost tubes and the furnace wall. By placing the external burners close to the wall, operating these external burners with 45 to 60%, preferably 50 to 55% of the power of the internal burners and essentially with the same input speed as the internal burners, it is possible to generate a profile of homogeneous temperature in the catalyst tubes. The inlet speed of the external burners is adjusted to be between 90 and 110%, preferably 95 to 105%, of the speed of the internal burners, so that there is a maximum deviation of 10%, preferably 5%, between the input speeds.
    [0036] Preferably, at least some of the burners' flames are directed from the top to the bottom of the furnace, to avoid any phenomenon of local heating.
    [0037] Even better results are obtained if the reactant runs through the catalyst tubes from the top to the bottom of the oven, with most of the reactant already being converted into the entry zone at the top of the oven, since there is the hottest point of the burner flames.
    [0038] To obtain the same inlet speed in the internal burners as in the external burners, it was found that, advantageously, the inlet speed is adjusted by air injection. By using air to adapt the input current, the combustion reaction in the burner is practically unaffected. Also, air is, of course, the cheapest gas.
    [0039] The claimed process leads to particularly good results if the process is a steam reforming process.
    [0040] The invention is now described in more detail on the basis of preferred embodiments and drawings. All features described or illustrated form the object of the invention, regardless of their combination in the claims or their previous reference.
    [0041] In the drawings:
    [0042] Figure. 1 shows the typical configuration of an oven, prior to an endothermic reaction in tubes containing catalyst;
    [0043] Figure. 2 shows the typical heat flux and temperature profile in the standpipe;
    [0044] Figure. 3 shows an illustration of the curvature of the flame;
    [0045] Figure. 4 shows the average amount of tubes, row by row, for a reformer furnace (8 rows of tubes) and a virtual 24-row tube furnace;
    [0046] Figure. 5 schematically shows the oven section, including the proposed configuration;
    [0047] Figure. 6 shows the normalized tube quantity, average row per row, for reference and optimized reformer configuration;
    [0048] Figure. 7 shows the normalized quantity for a standard tube compartment (17 tubes) in an 8-row tube reformer ((a) effective configuration (b) optimized configuration);
    [0049] Figure. 8 shows the realization of a burner in combination with a high-emissivity refractory layer;
    [0050] Figure. 9 shows the concept of high swirl flame;
    [0051] Figure. 10 shows the radiant burner concept for diffusion flame and premix;
    [0052] Figure. 11 shows the radiant burner for arranging tubes;
    [0053] Figure. 12 shows the realization of the oven ceiling as an irradiation wall;
    [0054] Figure. 13 shows options for concave roof configurations;
    [0055] Figure. 14 shows options for configurations with a convex roof;
    [0056] Figure. 15 shows a linear radiant ceiling burner.
    [0057] The Figure. 1 shows a typical arrangement of an overhead combustion furnace 1 used to obtain a synthesis gas from a feed (reagent), which comprises, for example, methane and steam. Catalyst tubes 2 are provided in several rows inside furnace 1. The feed is provided through tubes 2 from top to bottom, from which the resulting product is taken, for example, a synthesis gas, comprising hydrogen, carbon monoxide and waste. Between the rows of tubes, 3 burners fire vertically from the bottom to the top. The resulting flue gases are removed through exhaust tunnels 4.
    [0058] Typical vertical profiles for heat flux and temperature are drawn in the Figure. 2. It is evident that the heat flux and temperature profile are coupled to each other. The denser the heat flow and the temperature profile is at the top of the tube, the higher the amount of heat for the tube at the same temperature and the higher the capacity of the process gas stream amount, to the same amount of conversion.
    [0059] The Figure. 3 is an illustration of the flame curvature for 4 and 8 rows of tubes (only half the furnace was simulated for symmetry reasons). Fluid and jet mechanism theory defines the typical current arrangement within a high combustion furnace, which means the jet aspiration of hot burnt gases from the side burners towards the center in the middle of the furnace. If the lower power or amounts of current along the sidewalls lead to a lower velocity, this reinforces the bending effect of the side flames towards the center, due to the weaker thrust of the side jets.
    [0060] The Figure. 4 shows the simulated average number of tubes per row for a reformer (furnace) with a furnace with 24 rows of tubes (only one half of the furnace was simulated for symmetry reasons). To face the phenomenon of bending effect, the thrust of the rows of side burners has been increased, step by step, up to 78% of the internal burner power. The curvature of the flame is not suppressed, and the increase in power creates a superheated region on the side of the furnace, whose peak value is located in the second row of wall tubes, due to the hot flue gas, which flows through the first row of tubes and heat the next row.
    [0061] Figure.5 shows the modification of the configuration, as proposed with the present invention, with two channels 5, 6 being defined by the furnace wall 1a and the catalyst tubes 2. The distance d between two rows of tube of catalyst 21 and 22 defines the central channel 5. Internal burners 3a are centrally positioned between tubes 21 and 22 in the roof 1b of the furnace 1. In the channel 6 defined between the external catalyst tube 21 and the wall of the furnace 1a, external burners or Sides 3b are arranged on the roof 1b of the oven. The dimension d1 of the outer channel 6 is adjusted so that its ratio to the distance d is the same as the power ratio of the outer and inner burners, viz. 45 to 60%, preferably 50 to 58%, and particularly preferably approximately 55% of the diameter d.
    [0062] The configuration described above was simulated using the simulation tool SMR3D (Air Liquide patented tool based on a Computational Fluid Dynamic (CFD) tool, coupled to a reformer tube model). The simulation result is presented in the Figures. 6 and 7 and compared to a reference configuration. The optimized configuration of the present invention results in much better quantity homogeneity on the scale of the reformer. The standard deviation of the number of tubes was decreased and optimized - row by row - to 1% vs. 4% in the reference case and as shown in the Figure. 7, tube by tube, for 3.5% vs. 6.5 in the reference case.
    [0063] The Figure. 8a shows the simplest realization of a burner 3, in combination with a high-emissivity refractory layer 7 provided inside the roof of the furnace 1b. The high-emissivity refractory layer 7 can be formed of bricks, thin plates or a coated layer , with the high emissivity resulting from intrinsic material properties, for example, using SiC boards, or from surface treatment or texturing, for example, using ceramic foam boards. A row of separate reduced power jet 3 burners forms a continuous flat flame. Compared with the prior art, the proposed innovative realization uses jet flame burners arranged in a continuous flame, with a large number of disposed air and fuel injection, for example, between 10 and 30 injectors per meter, compared with burner every 2 to 6 meters as proposed in prior art configurations.
    [0064] For the realization of more efficient heat transfer, 8-wall burners can be based on a radial burner technology as shown in Figure. 8b, or in a ramp wall burner technology as shown in Figure. 8c, equally arranged in a zigzag pattern with the tubes.
    [0065] As shown in the Figure. 9, it is also possible to carry out the combustion technology of the swirling sphere flame associated with a high-emissivity layer 7 on the furnace roof 1b. In it, the flame itself is captured in a recirculation zone, when they comprise, as well as the oxygen and/or steam source is recirculated from a lower point of the flame, back towards the furnace roof.
    [0066] The Figure. 10 shows two embodiments of the invention using a cylindrical radiant burner unit of two possible types: Figure 10a shows a diffusion flame enclosed in a radiant shield 9 . 10 passes to let flue gases enter the flame root by a Venturi effect are recommended, to obtain low NOx amounts. Dilution of combustion reagents with flue gas reduces the maximum flame temperature. Both dilution and temperature lower the kinetics of NOx formation.
    [0067] The combustion previously mixed with connection of the flame itself in a porous form is presented in the Figure. 10b. Combustion reaction takes place within the porous medium, which is heated and emits radiation towards the tubes in front of it. The main advantage of this technology is that the irradiation can be located in the optimal location, with regard to the transfer of heat to the tubes.
    [0068] The radiant casing is made of high temperature resistant material, such as porous ceramic foam, with high emissivity (SiC, Al2O3, ZrO2).
    [0069] The use of radiating burners makes it possible to configure the furnace with pavement, tube to tube, of optimized burner, which minimizes the circumferential flow inhomogeneities, as shown in the Figure. 11. Two pipe pavings are proposed: Figure. 11a shows a square tube pavement, while Figure. 11b shows a hexahedral tube shim with a standard burner.
    [0070] Figure.12 shows the realization of burners, which heat the roof of furnace 1b itself and use this roof as an irradiation wall. As shown in Figure. 12a, it is possible to configure the high insulation, low heat conductivity refractory lining, in a convex shape or as shown in the Figure. 12b, concave.
    [0071] The Figure. 13 shows different burner configurations, which can be realized in a concavely formed burner ceiling. The cross-sectional view for the two oblique radiating walls 1c is illustrated in the Figure. 13a, where the optimum angle Ca is below or around 50°, and the horizontal concave roof width Cw is set based on the pipe corridor width W and the angle Ca, so that sufficient space is maintained to arrange the burners correspondingly.
    [0072] In the Figure. 13b, typical jet burners 3 as shown in the Figure. 8, are arranged in lines to be directed downwards along the oblique radiating walls 1c on each side of the concave roof.
    [0073] The Figure. 13c has the same type of configuration with a continuous linear wall burner.
    [0074] In Figure.13d, typical radial wall burners are arranged in the concave roof, with L spacing, so that the best compromise between homogeneity of heat fluxes and reduction in the number of burners is found. It can typically correspond to one burner for every 2 to 8 tubes.
    [0075] Finally, the Figure. 13e features a configuration, where classic high swirl burners are installed in the concave ceiling.
    [0076] The Figure. 14 shows a convex roof configuration ("pointed roof"). In the figure. 14a, wall burners 3 are arranged around the convex shape, with downward combustion; in the figure. 14b, the burners 3 are arranged inside the convex roof, so that the flames are directed upwards from the pointed end to increase the radiation area covered by the flames, and therefore transfer efficiency to the tubes 2.
    [0077] As shown in Figure. 15, it is also possible to obtain a porous combustion chamber in which at least one high-powered burner is combusted. Openings near the flame root (furnace sidewalls 1a) can be added to let flue gases recirculate from the furnace atmosphere to the gas generator chamber by the section pressure of the Venturi effect. The configuration shown in Figure. 15a shows a single burner arrangement with zigzag combustion from one tube-to-tube corridor to another. This configuration saves you the capital costs of several unit burners, compared to the prior art, where up to 15 or 20 per row are used in a large, high-burning reformer, which can be replaced by one or two in the present mode. . A more reliable setup is to have two per anal radiation burners, as shown in the Figure. 15b, so that the performance of the furnace is less critically affected in the case of burners not accepted downwards.
    [0078] LIST OF REFERENCE NUMBERS 1 furnace 1st furnace wall 1b furnace roof 1c oblique furnace wall 2 tube 3 burner 3a internal burner 3b external burner 4 exhaust tunnel 5 central channel 6 external channel 7 high emissivity refractory layer 8 wall burner 9 pass radiation shield
    权利要求:
    Claims (15)
    [0001]
    1. Furnace for carrying out an endothermic process comprising tubes (2) containing a catalyst to convert a gaseous feed, wherein said tubes (2) are positioned inside the furnace (1), internal burners (3a) mounted on the roof of the furnace ( 1b) between the tubes (2) and the external burners (3b) mounted on the roof of the furnace (1b) between the tubes (2) and a wall of the furnace (1a), characterized in that the external burners (3b) are positioned so that the distance from the central axis of the external burners (3b) to the furnace wall (1a) is less than 25% of the distance between the outermost tubes and the furnace wall (1a) and that the external burners (3b) they are configured to operate with 45 to 60% of the power of the internal burners (3a) and with an input speed between 90 and 110% of the input speed of the internal burners (3a).
    [0002]
    2. Oven, according to claim 1, characterized in that the tubes (2) are positioned in rows and that the ratio of the distance between the oven wall (1a) and the first row of tubes in relation to the space between two rows of adjacent tubes correspond to the ratio between the power of the external burners and the power of the internal burners (3a, 3b).
    [0003]
    3. Oven, according to claims 1 or 2, characterized in that at least a part of the oven roof (1b) is provided with a solid surface of high emissivity (7) and resistant to temperature.
    [0004]
    4. Furnace according to claim 3, characterized in that the solid surface of high emissivity (7) contains silicon carbide or porous ceramic foams.
    [0005]
    5. Furnace according to any one of the preceding claims, characterized by the fact that at least some of the burners (3a, 3b) are jet burners.
    [0006]
    6. Furnace according to any one of claims 1 to 4, characterized by the fact that at least some of the burners (3a, 3b) are burners with high swirl ball flame technology.
    [0007]
    7. Furnace, according to any one of the preceding claims, characterized in that at least some of the burners (3a, 3b) are arranged so that the flame is formed on a porous radiant shield.
    [0008]
    8. Furnace according to claim 7, characterized in that at least some of the burners (3a, 3b) are arranged in a square or hexahedral configuration in relation to the catalyst tubes (2).
    [0009]
    9. Furnace according to claim 7 or 8, characterized in that the length of the radiant shield is between 10 and 40% of the length of the tube containing catalyst.
    [0010]
    10. Oven according to any one of the preceding claims, characterized in that at least a part of the oven roof (1a) is designed to have a convex or concave shape.
    [0011]
    11. Process for operating a furnace to perform an endothermic process with tubes (2) containing catalyst positioned inside the furnace to convert a gaseous feed and which are heated by internal burners (3a) mounted on the furnace roof (1b) between the tubes (2) and by external burners (3b) mounted on the furnace roof (1b) between the tubes (2) and the furnace wall (1a), characterized by the fact that the external burners (3b) are positioned so that the distance from the central axis of the external burners to the furnace wall is less than 25% of the distance between the outermost tubes and the furnace wall, that the external burners (3b) are operated with 45 to 60% of the power of the internal burners 3a) and that the input speed of the external burners (3b) be adjusted to be between 90 and 110% of the input speed of the internal burners (3a).
    [0012]
    12. Process according to claim 11, characterized in that at least some of the burners' flames are directed from above to the bottom of the furnace (1).
    [0013]
    13. Process according to claim 11 or 12, characterized in that the feed flows through the catalyst tubes (2) arranged vertically, from top to bottom of the furnace (1).
    [0014]
    14. Process according to any one of claims 11 to 13, characterized in that the inlet speed is adjusted by air injection.
    [0015]
    15. Process according to any one of claims 11 to 14, characterized in that the endothermic process is a steam reforming process.
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    引用文献:
    公开号 | 申请日 | 公开日 | 申请人 | 专利标题
    SU1078193A1|1968-02-26|1984-03-07|Kucherov Aleksandr S|Steam generator|
    JPH05332509A|1992-05-29|1993-12-14|Kuwahara Seisakusho:Kk|Inter-furnace discharged gas circulation type low nox burner|
    RU2135891C1|1997-12-23|1999-08-27|Дзержинская ТЭЦ АО "Нижновэнерго"|Furnace|
    DE10333854A1|2003-07-24|2005-02-17|Uhde Gmbh|Tubular cracking furnace used for reforming hydrocarbons e.g. to produce synthesis gas, comprises vertical cracker tubes, downward pointing burners and wedge shaped horizontal ceramic tunnels for removing flue gas|
    DE10357064A1|2003-12-04|2005-07-07|Uhde Gmbh|synthesis furnace|
    KR100590401B1|2004-03-15|2006-06-19|주식회사 경동세라텍|Firing kiln for expansion perlite|
    US7686611B2|2005-11-03|2010-03-30|Air Products And Chemicals, Inc.|Flame straightening in a furnace|
    EA027523B1|2009-06-24|2017-08-31|Тиссенкрупп Уде Гмбх|Primary reformer having variable smoke gas flow|
    US8545213B2|2010-03-09|2013-10-01|Air Products And Chemicals, Inc.|Reformer and method of operating the reformer|US9272905B2|2014-02-27|2016-03-01|Honeywell International, Inc.|Method for optimizing down fired reforming furnaces|
    EP3153465B1|2015-10-05|2020-01-01|L'Air Liquide Société Anonyme pour l'Etude et l'Exploitation des Procédés Georges Claude|Reformer for producing synthesis gas|
    PL3153464T3|2015-10-05|2020-03-31|L'Air Liquide Société Anonyme pour l'Etude et l'Exploitation des Procédés Georges Claude|Steam reformer for the production of synthesis gas|
    FR3043185B1|2015-11-02|2019-07-12|L'air Liquide, Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude|METHOD FOR IMPROVING THE THERMAL EFFICIENCY OF A REFORMING OVEN|
    PL3182003T3|2015-12-15|2021-10-25|L'air Liquide, Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude|Apparatus for endothermic process with improved burners arrangement|
    ES2803778T3|2016-02-04|2021-01-29|Technip France|Method for reducing temperature spread in a reformer|
    ES2738389T3|2016-08-02|2020-01-22|Air Liquide|Device for endothermic process with improved tube arrangement|
    KR20190077388A|2016-10-25|2019-07-03|테크니프 프랑스 에스.아.에스.|Catalyst tube for reforming|
    KR20180078364A|2016-12-29|2018-07-10|주식회사 효성|Fired heater|
    WO2018228777A1|2017-06-14|2018-12-20|L'air Liquide, Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude|Apparatus for endothermic process with improved outer burners arrangement|
    US20210362114A1|2018-06-28|2021-11-25|Haldor Topsøe A/S|Catalytic reactor comprising metal radiation surfaces|
    EP3647658B1|2018-11-01|2021-04-14|L'air Liquide, Société Anonyme Pour L'Étude Et L'exploitation Des Procédés Georges Claude|Furnace for endothermic process and process for operating a furnace with improved burner arrangement|
    WO2020260589A1|2019-06-28|2020-12-30|Technip France|Method of loading a tubular reactor with a catalyst tube assembly, and a catalyst tube assembly for a tubular reactor|
    US11110424B2|2019-11-18|2021-09-07|Praxair Technology, Inc.|Reformer box with reformer tunnel including tunnel port|
    EP3838397A1|2019-12-19|2021-06-23|L'air Liquide, Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude|Reformer furnace|
    法律状态:
    2018-11-21| B06F| Objections, documents and/or translations needed after an examination request according [chapter 6.6 patent gazette]|
    2020-04-22| B06U| Preliminary requirement: requests with searches performed by other patent offices: procedure suspended [chapter 6.21 patent gazette]|
    2021-03-09| B09A| Decision: intention to grant [chapter 9.1 patent gazette]|
    2021-05-04| B16A| Patent or certificate of addition of invention granted [chapter 16.1 patent gazette]|Free format text: PRAZO DE VALIDADE: 20 (VINTE) ANOS CONTADOS A PARTIR DE 14/08/2013, OBSERVADAS AS CONDICOES LEGAIS. |
    优先权:
    申请号 | 申请日 | 专利标题
    EP12184303.1A|EP2708812B1|2012-09-13|2012-09-13|Process and apparatus for endothermic reactions|
    EP12184303.1|2012-09-13|
    PCT/EP2013/066998|WO2014040815A1|2012-09-13|2013-08-14|Process and apparatus for endothermic reactions|
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