JP2018193507A - Gas reforming furnace and method for reforming pyrolysis gas - Google Patents

Abstract

To provide a gas reforming furnace that can easily and efficiently utilize the pyrolysis gas.SOLUTION: A furnace body 2 of a gas reforming furnace 1 is provided with first and second filling spaces 21 and 22 filled with a filling material. The first and second filling spaces have the pyrolysis gas supplied by a supply adjusting section 3 through first and second supply flow channels 31 and 32. The pyrolysis gas flowing through each supply flow channel has a variable flow rate. The first and second filling spaces have a modifying agent supplied by a modifying agent supplying part 5, in which the modifying agent is for precipitates deposited on the filling material from pyrolysis gas, and the modifying agent reforms the precipitates into fuel gas. The supply adjusting section is controlled by a control unit 10, which can switch between a state in which the flow rate of the pyrolysis gas flowing through the first supply flow channel is smaller than that of the second supply flow channel and a state in which the pyrolysis gas flowing through the second supply flow channel is smaller than that of the first supply flow channel. As a result, the gas reforming furnace can easily and efficiently utilize the pyrolysis gas.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a gas reforming furnace and a pyrolysis gas reforming method.

Conventionally, raw materials containing carbon such as biomass have been gasified. In gasification of a raw material, pyrolysis gas is produced | generated by thermally decomposing the raw material, for example at 500-700 degreeC in a gasification furnace. The pyrolysis gas includes not only gas but also tar vapor and powder char. The pyrolysis gas is sent to a subsequent gas reforming furnace. Inside the gas reforming furnace, a high temperature state of, for example, 800 to 1200 ° C. is maintained and steam is blown in by partial combustion by supplying oxygen, heating with a high temperature gas, or heating by a heater. Thereby, the tar and char in the pyrolysis gas are steam reformed and converted into a fuel gas such as hydrogen (H ₂ ) or carbon monoxide (CO). The reformed pyrolysis gas is used for power generation in an internal combustion engine such as a gas engine after heat recovery in a boiler and removal of impurities and the like in a gas purification unit.

  In patent document 1, the carbonaceous solid which has carbon as a main component adheres to the surface of a porous mineral particle by making the tar containing gas generated by thermal decomposition of biomass contact a porous mineral particle at 400-1000 degreeC. And a method for producing a carbon support is disclosed. In addition, the carbon carrier is used as a hydrogen gas generation source by a water gasification reaction in an external power generation device, and power generation is performed by a fuel cell using the generated hydrogen as a fuel. Patent Document 2 discloses a technique for decomposing a tar content contained in a combustible gas gas by a metal catalyst.

Japanese Patent No. 5679160 JP 2010-1111779 A

  By the way, in the method of Patent Document 1, a carbon carrier is generated from a pyrolysis gas, and a large amount of fuel gas is generated from the pyrolysis gas by using the carbon carrier as a hydrogen gas generation source. Gas can be used efficiently. However, a complicated operation of taking out the carbon carrier and generating fuel gas from the carbon carrier in another apparatus is required.

  This invention is made | formed in view of the said subject, and aims at utilizing a pyrolysis gas easily and efficiently.

  The invention according to claim 1 is a gas reforming furnace for reforming a pyrolysis gas supplied from a gasification furnace, the furnace body having a first filling space and a second filling space filled with a filler. And a first supply passage and a second supply passage connected to the first filling space and the second filling space, respectively, and the pyrolysis gas is passed through the first supply passage and the second supply passage. And supply to the first filling space and the second filling space, and a supply adjusting unit capable of changing a flow rate of the pyrolysis gas flowing through each supply flow path, and supply of an oxidizing agent to the pyrolysis gas Or a filling space heating unit that heats the first filling space and the second filling space by a heater, and the pyrolysis gas on the filling in the first filling space and the second filling space. Supplying modifier to the deposit Thus, the flow rate of the pyrolysis gas flowing through the first supply flow path is controlled by controlling the supply of the modifier supply unit that reforms the precipitate into fuel gas. A control unit that switches between one state smaller than the flow path and another state in which the flow rate of the pyrolysis gas flowing in the second supply flow path is smaller than that of the first supply flow path. The precipitate in the first filling space decreases, the precipitate in the second filling space increases, and in the other state, the precipitate in the second filling space decreases, and The deposits in the first filling space increase.

  Invention of Claim 2 is the gas reforming furnace of Claim 1, Comprising: The said modifier supply part separately supplies the said modifier to the said 1st filling space and the said 2nd filling space. The flow rate of the modifier supplied to the second filling space in the one state is smaller than that in the other state, and is supplied to the first filling space in the other state. The flow rate of the modifier is smaller than the one state.

  Invention of Claim 3 is a gas reforming furnace of Claim 1 or 2, Comprising: The said filler is a porous body.

  Invention of Claim 4 is a gas reforming furnace as described in any one of Claim 1 thru | or 3, Comprising: The said filling space heating part is the said 1st filling space and the said 2nd filling space in the said 2nd filling space. Oxidizing agents can be supplied separately.

  Invention of Claim 5 is a gas reforming furnace of Claim 4, Comprising: The said furnace main body has a main body flow path through which the said pyrolysis gas flows, The upstream space in the said main body flow path Includes the first filling space, the downstream space includes the second filling space, and in the other state, the flow rate of the oxidant supplied to the second filling space is higher than that in the one state. small.

  The invention according to claim 6 is a pyrolytic gas reforming method in a gas reforming furnace, wherein the gas reforming furnace has a first filling space and a second filling space filled with a filler. And a first supply channel and a second supply channel connected to the first filling space and the second filling space, respectively, and the pyrolysis gas supplied from a gasification furnace is supplied to the first supply channel and A supply adjusting unit that supplies the first filling space and the second filling space via the second supply flow path and is capable of changing a flow rate of the pyrolysis gas flowing through each supply flow path; and the pyrolysis gas In the filling space heating section for heating the first filling space and the second filling space by supplying an oxidant to the heater or by a heater, and the thermal decomposition in the first filling space and the second filling space Deposition from the gas on the packing A reformer supply unit that reforms the precipitate into a fuel gas by supplying a reformer to the product, and the pyrolysis gas reforming method uses a) the supply adjustment unit Forming a state in which the flow rate of the pyrolysis gas flowing through the first supply flow path is smaller than that of the second supply flow path; and b) using the supply adjusting unit, the second supply flow path Forming another state in which the flow rate of the pyrolysis gas flowing through the first supply flow path is smaller than that in the first supply flow path, and in the one state, the precipitate in the first filling space is reduced, and The precipitate in the second filling space increases, and in the other state, the precipitate in the second filling space decreases, and the precipitate in the first filling space increases.

  According to the present invention, the pyrolysis gas can be used easily and efficiently.

It is a figure which shows the structure of the gasification system which concerns on 1st Embodiment. It is a figure which shows the flow of the process which reforms pyrolysis gas. It is a figure which shows the structure of an experimental apparatus. It is a photograph which shows the reforming furnace of an experimental apparatus. It is a photograph which shows the reforming furnace of an experimental apparatus. It is a figure which shows the other example of a gas reforming furnace. It is a figure which shows the gas reforming furnace which concerns on 2nd Embodiment. It is a figure which shows the other example of a gas reforming furnace.

(First embodiment)
FIG. 1 is a diagram showing a configuration of a gasification system 8 according to a first embodiment of the present invention. The gasification system 8 includes a gasification furnace 81, a gas reforming furnace 1, a boiler 82, a gas purification unit 83, an induction fan 84, a gas engine 85, and a chimney 86. In the gasification system 8, an entire flow path is formed through the gasification furnace 81, the gas reforming furnace 1, the boiler 82, the gas purification unit 83, the induction fan 84, the gas engine 85, and the chimney 86 in this order. When the induction fan 84 is driven, a pyrolysis gas, which will be described later, generated in the gasification furnace 81 flows toward the chimney 86 through the entire flow path.

  The gasification furnace 81 is, for example, a kiln gasification furnace, a fixed bed gasification furnace, a fluidized bed gasification furnace, or the like. Waste or biomass (hereinafter simply referred to as “raw material”) crushed to a predetermined size by the crusher 811 is charged into the gasifier 81. Examples of the raw material include general waste, industrial waste, sludge, and woody biomass. The raw material is pyrolyzed and gasified by being heated at 500 to 700 ° C., for example. Thereby, pyrolysis gas is produced | generated. The pyrolysis gas includes not only gas but also tar vapor and powder char. The pyrolysis gas is supplied to the gas reforming furnace 1. Incombustible materials generated in the gasification furnace 81 are recovered as appropriate.

  In the gas reforming furnace 1, reforming of tar, char and the like contained in the pyrolysis gas is performed. The configuration of the gas reforming furnace 1 will be described later. The pyrolysis gas reformed by the gas reforming furnace 1 (hereinafter referred to as “reformed gas”) flows into the boiler 82. In the boiler 82, the temperature of the reformed gas decreases due to heat exchange with the circulating water that circulates inside. The reformed gas flows from the boiler 82 into the gas purification unit 83. In the gas purification unit 83, the reformed gas is subjected to a purification process such as dust and mist removal, desalting, desulfurization, and heavy metal removal. The reformed gas after the purification process is, for example, about 50 ° C., and is supplied to the gas engine 85 via the induction fan 84. The gas engine 85 generates power using the reformed gas as fuel. The exhaust gas obtained by burning the reformed gas in the gas engine 85 is discharged to the atmosphere via the chimney 86. The exhaust gas is preferably heat-exchanged before reaching the chimney 86.

  The circulating water in the boiler 82 becomes steam by heat exchange with the reformed gas. The water vapor is led to a steam sump 820. A part of the water vapor in the steam sump 820 is supplied to a later-described modifier supply unit 5 in the gas reforming furnace 1. Another part of the water vapor is supplied to the gasification furnace 81 and used for heating (drying) the raw material. The remainder of the steam is used to drive the steam turbine 821 and then returned to the inside of the boiler 82 as circulating water.

  The gas reforming furnace 1 includes a furnace body 2, a supply adjustment unit 3, a filling space heating unit 4, a modifier supply unit 5, and a control unit 10. The control unit 10 is responsible for overall control of the gas reforming furnace 1. The control unit 10 may take overall control of the gasification system 8.

  The furnace body 2 has, for example, a substantially cylindrical shape. A first inlet 201 connected to the gasification furnace 81 is provided at one end of the furnace body 2. At the other end, an outlet 203 connected to the boiler 82 is provided. In the furnace body 2, a second inlet 202 is provided between the first inlet 201 and the outlet 203. Pyrolysis gas from the gasification furnace 81 flows into the furnace body 2 through the first inlet 201 or the second inlet 202. The pyrolysis gas flows inside the furnace body 2 toward the outlet 203 and flows out to the boiler 82 through the outlet 203. Thus, in the furnace main body 2, the main body flow path 200 through which the pyrolysis gas flows is formed. The shape of the furnace body 2 may be changed as appropriate, and may be, for example, a U-shape.

  The furnace body 2 includes a first holding member 211 and a second holding member 221. The first holding member 211 and the second holding member 221 are separated from each other in the flow direction of pyrolysis gas from the first inlet 201 to the outlet 203 (hereinafter referred to as “gas flow direction”) in the main body flow path 200. Arranged. With respect to the gas flow direction, the first holding member 211 is disposed between the first inlet 201 and the second inlet 202, and the second holding member 221 is interposed between the second inlet 202 and the outlet 203. Be placed. In the present embodiment, the gas flow direction is parallel to the vertical direction. Each holding member 211, 221 extends approximately perpendicular to the gas flow direction and is connected to the entire circumference of the side wall of the furnace body 2. The holding members 211 and 221 are formed with a plurality of (multiple) holes uniformly dispersed, and the pyrolysis gas passes through the plurality of holes. The holding members 211 and 221 are made of, for example, ceramics, porcelain, refractory material, concrete, metal or the like.

  A filler is filled (deposited) on each holding member 211, 221. The filling is formed of a material having high heat resistance. The filler is preferably a porous body made of ceramics, for example, a ceramic ball. The filling spreads over the entire upper surface of the holding members 211 and 221. The filling is held by holding members 211 and 221 from below. In the following description, the space 21 filled with the filling material on the first holding member 211 is referred to as a “first filling space 21”, and the space 22 filled with the filling material on the second holding member 221 is referred to as a “second filling space”. It is referred to as “filling space 22”. In the main body channel 200, the space on the upstream side (first inflow port 201 side) with respect to the first holding member 211 includes the first filling space 21, and the downstream side with respect to the first holding member 211 (outlet port 203 side). The space includes the second filling space 22.

  The supply adjusting unit 3 includes a common flow path 30, a first supply flow path 31, and a second supply flow path 32. One end of the common flow path 30 is connected to the gasification furnace 81. The other end of the common channel 30 is branched into two and connected to one end of the first supply channel 31 and the second supply channel 32. The other ends of the first supply channel 31 and the second supply channel 32 are connected to the first inlet 201 and the second inlet 202 of the furnace body 2, respectively. The first supply flow path 31 is connected to the first filling space 21 through a space in the furnace body 2 near the first inlet 201. The second supply channel 32 is connected to the second filling space 22 through a space in the furnace body 2 near the second inlet 202. The pyrolysis gas generated in the gasification furnace 81 is supplied to the first filling space 21 and the second filling space 22 via the first supply channel 31 and the second supply channel 32. Dampers 311 and 321 are provided in the supply passages 31 and 32, respectively, and the flow rate of the pyrolysis gas flowing through the supply passages 31 and 32 can be changed. The first supply channel 31 and the second supply channel 32 may be directly connected to the gasification furnace 81 without the common channel 30 interposed.

  The filling space heating unit 4 includes a first oxidant nozzle 41, a second oxidant nozzle 42, and an oxidant supply unit 43. The first oxidant nozzle 41 is disposed at a position upstream of the first filling space 21 in the main body flow path 200, and is connected to the oxidant supply unit 43 via the damper 411. The second oxidant nozzle 42 is disposed at a position upstream of the second filling space 22 and downstream of the first filling space 21 in the main body flow path 200, and is connected to the oxidant supply unit 43 via the damper 421. . The oxidant supply unit 43 supplies an oxidant to the first oxidant nozzle 41 and the second oxidant nozzle 42. An oxidizing agent is a gas containing oxygen, for example, air. The oxidant may be oxygen itself. An oxidant is supplied to the first filling space 21 by the first oxidant nozzle 41, and an oxidant is supplied to the second filling space 22 by the second oxidant nozzle 42. In the gas reforming furnace 1, a plurality of first oxidant nozzles 41 may be provided, or a plurality of second oxidant nozzles 42 may be provided.

  The modifier supply unit 5 includes a first modifier nozzle 51 and a second modifier nozzle 52. The first modifier nozzle 51 is disposed at a position upstream of the first filling space 21 in the main body flow path 200, and is connected to the steam sump 820 via the damper 511. The second modifier nozzle 52 is disposed at a position upstream of the second filling space 22 and downstream of the first filling space 21 in the main body channel 200, and is connected to the steam reservoir 820 via the damper 521. The water vapor in the steam sump 820 is supplied to the first modifier nozzle 51 and the second modifier nozzle 52 as a modifier. The modifier may be hydrogen peroxide gas or the like. A modifier is supplied to the first filling space 21 by the first modifier nozzle 51, and a modifier is supplied to the second filling space 22 by the second modifier nozzle 52. In the gas reforming furnace 1, a plurality of first modifier nozzles 51 may be provided, or a plurality of second modifier nozzles 52 may be provided. The water vapor supplied to the first modifier nozzle 51 and the second modifier nozzle 52 may be generated using heat of exhaust gas from the gas engine 85 or an external heat source.

  FIG. 2 is a diagram showing a flow of processing in which the gas reforming furnace 1 reforms the pyrolysis gas. In the reforming of the pyrolysis gas in the gas reforming furnace 1, step S11 and step S12 described later are alternately repeated. In the following description, attention is focused on step S11 performed immediately after one step S12 and step S12 performed immediately after step S11. In the reforming of the pyrolysis gas in the gas reforming furnace 1, the oxidant supply unit 43 always supplies the oxidant from the first oxidant nozzle 41 and the second oxidant nozzle 42 to the main body flow path 200 in principle. Has been done.

  In step S <b> 11, a state is formed in which the flow rate of the pyrolysis gas flowing through the first supply flow path 31 is smaller than the flow rate of the pyrolysis gas flowing through the second supply flow path 32 using the supply adjusting unit 3. In the present embodiment, the flow rate of the pyrolysis gas flowing through the first supply flow path 31 becomes substantially zero by closing the damper 311 of the first supply flow path 31. Further, when the damper 321 of the second supply channel 32 is opened, the pyrolysis gas is supplied from the second inlet 202 into the main body channel 200.

  The pyrolysis gas flows from the second inlet 202 toward the second filling space 22. At this time, the oxidant is supplied from the second oxidant nozzle 42 to the pyrolysis gas, and the gas contained in the pyrolysis gas partially burns. Thereby, for example, a high-temperature pyrolysis gas of 800 to 1200 ° C. flows into the second filling space 22. The pyrolysis gas that has reached the second filling space 22 flows downstream of the second filling space 22 in the main body flow path 200 via the gap between the fillings and the hole of the second holding member 221. . When the pyrolysis gas passes through the second filling space 22, the carbon component of the tar contained in the pyrolysis gas is on the surface of the packing (including the surface in the pores) as shown in the following chemical reaction formula. Precipitate. In other words, tar contained in the pyrolysis gas is collected (trapped) in the packing. At this time, fuel gas such as hydrogen is also generated.

  Typically, the deposit is a carbon-rich substance (carbon compound) and does not need to be pure carbon. In the second filling space 22, the amount of precipitates deposited on the filling material from the pyrolysis gas increases with the passage of time. By setting the temperature of the second filling space 22 to 800 to 1200 ° C., decomposition of tar contained in the pyrolysis gas, that is, precipitation of precipitates is likely to occur, and the trapping rate of tar may be close to 100%. It becomes possible. In the second filling space 22, the powdered char contained in the pyrolysis gas also adheres to the surface of the filling and is collected. Char that adheres to the filler may also be treated as a precipitate (the same applies hereinafter). Thus, most of tar and char contained in the pyrolysis gas are removed by the pyrolysis gas passing through the second filling space 22. Pyrolysis gas from which tar and the like have been removed (including combustion gas and generated fuel gas, the same applies hereinafter) reaches the outlet 203 and is discharged to the boiler 82.

  On the other hand, in the immediately preceding step S12, precipitates are deposited on the filling material in the first filling space 21 (precipitation deposition in the first filling space 21 will be described later). In step S11, the modifier is supplied from the first modifier nozzle 51 to the main body flow path 200, and the oxidant from the first oxidant nozzle 41 to the main body flow path 200 as described above. Is also provided. As described above, the oxidizing agent and the modifying agent are supplied to the deposit on the filling in the first filling space 21. In the 1st filling space 21, a part of deposit on a filling material burns with an oxidizing agent, and the 1st filling space 21 becomes high temperature. As a result, the other part of the precipitate is converted into a fuel gas such as hydrogen or carbon monoxide by a reforming reaction with a modifier (here, a steam reforming reaction) as shown in the chemical reaction formula below. (Modified)

  In the first filling space 21, the amount of precipitates on the filling decreases with the passage of time. In the first filling space 21, partial combustion of the fuel gas generated from the precipitate may also occur. The fuel gas and the combustion gas pass through the first filling space 21 and pass through the second filling space 22 together with the pyrolysis gas. Then, the fuel gas and the combustion gas are discharged to the boiler 82 as a reformed gas together with the pyrolysis gas from which tar and the like have been removed in the second filling space 22. In step S11 in this processing example, the flow rate of the modifier ejected from the second modifier nozzle 52 is smaller than the flow rate in step S12 described later, and preferably, the modifier from the second modifier nozzle 52 is changed. Is not ejected.

  Step S12 is performed when a predetermined time elapses after the supply of the pyrolysis gas from the second supply flow path 32 is started. In step S <b> 12, the supply adjusting unit 3 is used to form a state in which the flow rate of the pyrolysis gas flowing through the second supply flow path 32 is smaller than the flow rate of the pyrolysis gas flowing through the first supply flow path 31. In the present embodiment, the flow rate of the pyrolysis gas flowing through the second supply flow path 32 becomes substantially zero by closing the damper 321 of the second supply flow path 32. Further, when the damper 311 of the first supply flow path 31 is opened, the pyrolysis gas is supplied from the first inlet 201 into the main body flow path 200.

  The pyrolysis gas flows from the first inlet 201 toward the first filling space 21. At this time, an oxidant is supplied from the first oxidant nozzle 41 to the pyrolysis gas, and the gas contained in the pyrolysis gas partially burns. Thereby, high-temperature pyrolysis gas flows into the first filling space 21. The pyrolysis gas that has reached the first filling space 21 flows to the downstream side of the first filling space 21 in the main body channel 200 via the gap between the fillings and the hole of the first holding member 211. . When the pyrolysis gas passes through the first filling space 21, a carbon component of tar contained in the pyrolysis gas is deposited on the surface of the packing. In the first filling space 21, the amount of precipitates deposited on the filler from the pyrolysis gas increases with the passage of time. The powdered char contained in the pyrolysis gas also adheres to the surface of the filler and is collected. As described above, when the pyrolysis gas passes through the first filling space 21, most of tar and char contained in the pyrolysis gas are removed. The pyrolysis gas from which tar and the like are removed passes through the second filling space 22, reaches the outlet 203, and is discharged to the boiler 82.

  On the other hand, as described above, in step S <b> 11 immediately before, a precipitate is deposited on the filling in the second filling space 22. In step S12, the modifier is supplied from the second modifier nozzle 52 to the main body flow path 200, and the oxidant from the second oxidant nozzle 42 to the main body flow path 200 as described above. Is also provided. As described above, the oxidizing agent and the modifier are supplied to the deposit on the filling in the second filling space 22. In the second filling space 22, a part of the deposit on the filling is burned by the oxidizing agent, and the second filling space 22 becomes high temperature. As a result, the other part of the precipitate is converted into fuel gas by the reforming reaction by the modifier. Actually, since the pyrolysis gas flowing through the first filling space 21 and flowing into the second filling space 22 is at a high temperature, in step S12, the flow rate of the oxidant ejected from the second oxidant nozzle 42 is set as follows. It is possible to make it smaller than step S11.

  In the second filling space 22, the amount of precipitates on the filling decreases with the passage of time. In the second filling space 22, partial combustion of the fuel gas generated from the precipitate and partial combustion of the pyrolysis gas may also occur. The fuel gas and the combustion gas pass through the second filling space 22 and are discharged to the boiler 82 as reformed gas together with the pyrolysis gas from which tar and the like have been removed in the first filling space 21. In step S12 in the present processing example, the flow rate of the modifier ejected from the first modifier nozzle 51 is smaller than the flow rate in step S11. Preferably, the modifier is ejected from the first modifier nozzle 51. Not.

  Step S11 is performed when a predetermined time elapses after the supply of the pyrolysis gas from the first supply flow path 31 is started. Thus, step S11 and step S12 are repeated alternately. In other words, a state in which the precipitate in the first filling space 21 decreases and the precipitate in the second filling space 22 increases, the precipitate in the second filling space 22 decreases, and the first filling Other states in which the precipitates in the space 21 increase are alternately repeated. Thereby, the continuous operation of the gas reforming furnace 1 becomes possible without the filling spaces 21 and 22 being blocked.

  In the gas reforming furnace 1 (and the gas reforming furnace 1 in FIGS. 6 to 8 described later), by managing the duration of each step S11, S12, one filling space in which precipitates increase is closed. Before, switching to the other steps S12 and S11 is performed. Switching between step S11 and step S12 may be performed based on information other than time. For example, in the furnace body 2, a measurement unit is provided in the vicinity of the first inlet 201, the second inlet 202, and the outlet 203, and a measurement value such as temperature, pressure, or flow rate is acquired by the measurement unit, Switching between step S11 and step S12 may be performed by detecting a sign of blockage in the filling spaces 21, 22 where the deposits increase. Further, the switching may be performed by detecting the end point of the reforming of the precipitates in the filling spaces 21 and 22 where the precipitates are reduced based on the measured value. Furthermore, the amount of the oxidant ejected from each of the oxidant nozzles 41 and 42 may be controlled based on the measured value of the temperature. In the process of reforming the pyrolysis gas, precipitates increase in one filling space and precipitates decrease in both filling spaces 21 and 22 in addition to the state of steps S11 and S12 in which the precipitation decreases in the other filling space. A state where the matter increases or a state where the precipitate decreases may be included.

  Note that when the modifier is ejected from the second modifier nozzle 52 in step S11 and when the modifier is ejected from the first modifier nozzle 51 in step S12, the pyrolysis gas is generated. The contained tar is reformed to hydrogen or carbon monoxide (that is, fuel gas) by a steam reforming reaction shown in the following chemical reaction formula.

  Here, an experimental example will be described. FIG. 3 is a diagram illustrating a schematic configuration of the experimental apparatus 9. In the experimental apparatus 9, a quartz reaction tube having an inner diameter of 50 mm is used as the reforming furnace 91, and the reforming furnace 91 is filled with quartz beads 92 as a packing material. An electric heater 97 is provided around the reforming furnace 91, and the reforming furnace 91 is heated to a predetermined temperature. An inlet 911 is provided in the lid of the reforming furnace 91. Various gases can be supplied into the reforming furnace 91 through the inflow port 911. An outlet 912 from which fuel gas or the like is discharged is provided at the bottom of the reforming furnace 91.

In the first experiment, a gas containing simulated pyrolysis gas, oxygen (O ₂ ) gas and water vapor (H ₂ O) was supplied into the reforming furnace 91 from the inlet 911 under the conditions shown in Table 1. The simulated pyrolysis gas contains carbon dioxide (CO ₂ ), hydrogen (H ₂ ), carbon monoxide (CO), methane (CH ₄ ), nitrogen (N ₂ ), and toluene (C ₇ H ₈ ) as a simulated tar. Further included. Oxygen gas and water vapor correspond to the oxidant and modifier, respectively. Further, the electric heater 97 was controlled so that the temperature of the center portion of the reforming furnace 91 was 1200 ° C. In this way, tar removal of the simulated pyrolysis gas was performed, and precipitates were deposited on the quartz beads 92 from the simulated pyrolysis gas.

  FIG. 4 is a photograph showing the reforming furnace 91 (reaction tube) used in the actual experiment. The left photograph in FIG. 4 shows the reforming furnace 91 before the experiment, and the right photograph shows the reforming furnace 91 after the experiment. In the photograph on the right side, some quartz beads (see symbol A) are black, and it was confirmed that precipitates (carbon compounds) were deposited on the quartz beads. In addition, the temperature of the area | region where the deposit precipitated was 1000-1200 degreeC.

In the second experiment, with respect to the reforming furnace 91 obtained in the first experiment, a gas containing nitrogen (N ₂ ) gas and water vapor (H ₂ O) is introduced into the inlet 911 under the conditions shown in Table 2. Was supplied into the reforming furnace 91. Further, the electric heater 97 was controlled so that the temperature of the center portion of the reforming furnace 91 was 1200 ° C. In this way, the deposit on the quartz beads 92 was reformed into fuel gas with water vapor.

  FIG. 5 is a photograph showing the reforming furnace 91 (reaction tube) used in the actual experiment. The left photograph in FIG. 5 shows the reforming furnace 91 before the experiment, and the right photograph shows the reforming furnace 91 after the experiment. In the photograph on the left side, it was confirmed that the precipitate (see symbol A) adhering to the quartz beads was removed by steam reforming. In addition, the temperature of the area | region where the deposit was removed was 1000-1200 degreeC.

  Here, the process of the comparative example which produces | generates a carbon carrier from pyrolysis gas and uses the said carbon carrier as a hydrogen gas generation source like patent 5679160 (the said patent document 1) is assumed. In the process of the comparative example, a large amount of fuel gas is generated from the pyrolysis gas, that is, the pyrolysis gas can be used efficiently. However, a complicated operation of taking out the carbon carrier and generating fuel gas from the carbon carrier in another apparatus is required. In addition, when using miscellaneous raw materials such as municipal wastes, the quality and amount of pyrolysis gas are likely to fluctuate greatly and become extremely unstable. When the amount of the precipitate increases rapidly, the gap in the carbon carrier is closed.

  On the other hand, the furnace body 2 of the gas reforming furnace 1 is provided with a first filling space 21 and a second filling space 22 filled with a filler. The supply adjusting unit 3 supplies the pyrolysis gas to the first filling space 21 and the second filling space 22 via the first supply channel 31 and the second supply channel 32, and flows through the supply channels 31 and 32. The flow rate of the pyrolysis gas can be changed. In the first filling space 21 and the second filling space 22, the modifier supply unit 5 supplies a modifier to the precipitate deposited on the filler from the pyrolysis gas, and converts the deposit into fuel gas. Quality. And the control part 10 controls the supply adjustment part 3, and the one state where the flow volume of the pyrolysis gas which flows through the 1st supply flow path 31 is smaller than the 2nd supply flow path 32, and a 2nd supply flow path The other state in which the flow rate of the pyrolysis gas flowing through 32 is smaller than that of the first supply flow path 31 is switched. Thereby, in the said one state, the deposit in the 1st filling space 21 can be decreased, and the deposit in the 2nd filling space 22 can be increased, In the said other state, in the 2nd filling space 22 Precipitates can be reduced and precipitates in the first filling space 21 can be increased. As a result, the fuel gas can be generated from the precipitate without taking out the filler with the deposit attached to the outside, and the pyrolysis gas can be used easily and efficiently. Moreover, blockage in the furnace main body 2 due to precipitates can be prevented.

  In the gas reforming furnace 1, the flow rate of the modifier supplied to the second filling space 22 in the one state is smaller than that in the other state, and is supplied to the first filling space 21 in the other state. The flow rate of the modifier is smaller than the one state. Thereby, in each filling space 21 and 22, the carbon component of tar is positively deposited as a precipitate, and thereafter, the reforming (decomposition) of the precipitate is performed by the modifier. As a result, the tar contained in the pyrolysis gas can be efficiently removed as compared with the case where the modifier is simply supplied to the pyrolysis gas (when no deposit is deposited on the filler). Moreover, when the filler is a porous body, the amount of tar deposited can be easily increased.

  Here, the apparatus of the comparative example which decomposes | disassembles the tar in pyrolysis gas by using a noble metal catalyst is assumed. In the apparatus of the comparative example, acidic gas components such as sulfur (S) and chlorine (Cl) contained in the pyrolysis gas poison the catalyst and deactivate it. Moreover, the catalyst may be blocked by fly ash or the like. Therefore, it is necessary to install a demineralization desulfurization apparatus that processes acid gas components, a high-temperature dust removal apparatus that removes fly ash, and the like as a pretreatment apparatus, which increases the scale of the gasification system. There is also a problem that tar and precipitates adhere to the catalyst surface.

  On the other hand, the first filling space 21 and the second filling space 22 of the gas reforming furnace 1 do not require the catalyst function itself, so there is no concern about poisoning or blockage of the catalyst. The pre-processing device is also unnecessary. As a result, the gasification system 8 can be made small, and the manufacturing cost of the system can be reduced. Moreover, a relatively inexpensive packing such as ceramics can be used, and the manufacturing cost of the gas reforming furnace 1 can be reduced as compared with the apparatus of the comparative example.

  In the gas reforming furnace 1 of FIG. 1, the upstream space in the main body flow path 200 includes the first filling space 21, and the downstream space includes the second filling space 22. Therefore, in a state where the flow rate of the pyrolysis gas flowing through the first supply flow path 31 is larger than that of the second supply flow path 32 (the other state described above), the heat generated from the pyrolysis gas in the upstream space is reduced to the second level. It can be used in the filling space 22. As a result, the flow rate of the oxidant supplied to the second filling space 22 is smaller than that in the state where the flow rate of the pyrolysis gas flowing through the second supply flow channel 32 is larger than that of the first supply flow channel 31 (the one state described above). The amount of the oxidizing agent can be reduced. Further, in the above one state, the surplus of the modifier supplied from the first modifier nozzle 51 to the first filling space 21 can be used in the downstream space, and the modifier is used efficiently. can do.

  FIG. 6 is a view showing another example of the gas reforming furnace 1. In the gas reforming furnace 1 of FIG. 6, the first supply flow path 31 and the first discharge flow path 61 are connected to one end 281 of the furnace body 2. The second supply flow path 32 and the second discharge flow path 62 are connected to the other end 282 of the furnace body 2. In the example of FIG. 6, the first supply flow path 31 and the first discharge flow path 61 are coupled at the position P1 and connected to the furnace body 2 as one flow path. Similarly, the 2nd supply flow path 32 and the 2nd discharge flow path 62 couple | bond together in the position P2, and are connected to the furnace main body 2 as one flow path. Dampers 611 and 621 are provided in the discharge channels 61 and 62, respectively. The ends of the first discharge channel 61 and the second discharge channel 62 on the opposite side to the furnace body 2 are coupled to each other and connected to the boiler 82 as one channel.

  Inside the furnace body 2, a first oxidant nozzle 41 and a first modifier nozzle 51 are provided between the first filling space 21 and the end 281. An intermediate oxidizer nozzle 40 and an intermediate modifier nozzle 50 are provided between the first filling space 21 and the second filling space 22. A second oxidizer nozzle 42 and a second modifier nozzle 52 are provided between the second filling space 22 and the end 282.

  In the gas reforming furnace 1 of FIG. 6, the dampers 321 and 611 are opened and the dampers 311 and 621 are closed in step S <b> 11 of FIG. 2 in which the pyrolysis gas does not flow through the first supply flow path 31. Further, the oxidant is ejected from the second oxidant nozzle 42 and the intermediate oxidant nozzle 40, and the modifier is ejected from the intermediate modifier nozzle 50. Thereby, precipitates increase in the second filling space 22 and precipitates decrease in the first filling space 21. Further, heat generated from the pyrolysis gas between the end portion 282 and the second filling space 22 and in the second filling space 22 is used in the first filling space 21. Therefore, the flow rate of the oxidant ejected from the intermediate oxidant nozzle 40 can be reduced, and the amount of oxidant used can be reduced. In step S11, the modifier may be ejected from the second modifier nozzle 52 (the same applies hereinafter).

  In step S12 in which the pyrolysis gas does not flow through the second supply flow path 32, the dampers 311 and 621 are opened, and the dampers 321 and 611 are closed. Further, the oxidant is ejected from the first oxidant nozzle 41 and the intermediate oxidant nozzle 40, and the modifier is ejected from the intermediate modifier nozzle 50. Thereby, precipitates increase in the first filling space 21 and precipitates decrease in the second filling space 22. Further, heat generated from the pyrolysis gas between the end portion 281 and the first filling space 21 and in the first filling space 21 is used in the second filling space 22. Therefore, the flow rate of the oxidant ejected from the intermediate oxidant nozzle 40 can be reduced, and the amount of oxidant used can be reduced. In step S12, the modifier may be ejected from the first modifier nozzle 51 (the same applies hereinafter).

  In the gas reforming furnace 1 of FIGS. 1 and 6, the structure of the furnace body 2 can be simplified by providing the first filling space 21 and the second filling space 22 in one furnace. The first filling space 21 and the second filling space 22 may be provided in separate furnaces. Hereinafter, the gas reforming furnace 1 in which the first filling space 21 and the second filling space 22 are provided in separate furnaces will be described.

(Second Embodiment)
FIG. 7 is a diagram showing a gas reforming furnace 1 according to the second embodiment of the present invention. The furnace body 2 a of the gas reforming furnace 1 includes a first split furnace 291 and a second split furnace 292. Each of the split furnaces 291 and 292 has a substantially cylindrical shape, for example. The first supply flow path 31 is connected to one end of the first split furnace 291, and the first discharge flow path 61 is connected to the other end. Similarly, the second supply flow path 32 is connected to one end of the second split furnace 292, and the second discharge flow path 62 is connected to the other end. The first discharge channel 61 and the second discharge channel 62 are connected to the boiler 82.

  A first filling space 21 is provided inside the first dividing furnace 291, and a second filling space 22 is provided inside the second dividing furnace 292. The pyrolysis gas supplied from the first supply channel 31 into the first split furnace 291 passes through the first filling space 21 and then flows into the first discharge channel 61. Similarly, the pyrolysis gas supplied from the second supply channel 32 into the second split furnace 292 passes through the second filling space 22 and then flows into the second discharge channel 62. The first oxidant nozzle 41 and the first modifier nozzle 51 are disposed at a position upstream of the first filling space 21 in the first split furnace 291. The second oxidant nozzle 42 and the second modifier nozzle 52 are disposed at a position upstream of the second filling space 22 in the second dividing furnace 292.

  In the reforming of the pyrolysis gas in the gas reforming furnace 1 of FIG. 7, the flow rate of the pyrolysis gas flowing through the first supply flow path 31 is smaller than the flow rate of the pyrolysis gas flowing through the second supply flow path 32. It is formed (FIG. 2: Step S11). At this time, in the second split furnace 292, the oxidant is supplied from the second oxidant nozzle 42 to the pyrolysis gas, and the gas contained in the pyrolysis gas partially burns. And when pyrolysis gas passes the 2nd filling space 22, the carbon component of the tar contained in pyrolysis gas precipitates on the surface of a filling. The pyrolysis gas from which tar or the like has been removed in the second filling space 22 is discharged to the boiler 82 via the second discharge channel 62. In the first split furnace 291, the oxidant and the modifier are supplied from the first oxidant nozzle 41 and the first modifier nozzle 51 to the inside. Thereby, a part of the deposit on the packing in the first filling space 21 burns, and the other part of the deposit is reformed into the fuel gas by the reforming reaction by the modifier. The fuel gas and the combustion gas are discharged to the boiler 82 via the first discharge channel 61.

  When a predetermined time has elapsed from the start of step S11, a state is formed in which the flow rate of the pyrolysis gas flowing through the second supply flow path 32 is smaller than the flow rate of the pyrolysis gas flowing through the first supply flow path 31 (step S12). . At this time, in the first split furnace 291, the oxidant is supplied from the first oxidant nozzle 41 to the pyrolysis gas, and the gas contained in the pyrolysis gas partially burns. And when pyrolysis gas passes the 1st filling space 21, the carbon component of tar contained in pyrolysis gas precipitates on the surface of a filling. The pyrolysis gas from which tar and the like have been removed in the first filling space 21 is discharged to the boiler 82 via the first discharge passage 61. In the second divided furnace 292, the oxidant and the modifier are supplied from the second oxidant nozzle 42 and the second modifier nozzle 52 to the inside. Thereby, a part of the deposit on the packing in the second filling space 22 burns, and the other part of the deposit is reformed into the fuel gas by the reforming reaction by the modifier. The fuel gas and the combustion gas are discharged to the boiler 82 via the second discharge channel 62. Steps S11 and S12 are alternately repeated.

  As described above, also in the gas reforming furnace 1 of FIG. 7, one state in which the precipitates in the first filling space 21 decrease and the precipitates in the second filling space 22 increase, and the second filling space. The other state in which the precipitate in 22 decreases and the precipitate in the first filling space 21 increases is switched. Accordingly, fuel gas can be generated from the precipitate without taking out the filler with the deposit attached to the outside, and the pyrolysis gas can be used easily and efficiently. Moreover, blockage in the furnace body 2a due to precipitates can be prevented.

  FIG. 8 is a view showing another example of the gas reforming furnace 1. In the gas reforming furnace 1 of FIG. 8, a first auxiliary flow path 231 and a second auxiliary flow path 232 are added to the gas reforming furnace 1 of FIG. The first auxiliary channel 231 communicates the downstream end of the second split furnace 292 and the upstream end of the first split furnace 291. The second auxiliary channel 232 communicates the downstream end of the first split furnace 291 and the upstream end of the second split furnace 292. In addition, dampers 233, 234, 611, and 621 are added to the first auxiliary channel 231, the second auxiliary channel 232, the first discharge channel 61, and the second discharge channel 62, respectively. Other configurations are the same as those in FIG. 7, and the same reference numerals are given to the same configurations.

  In the gas reforming furnace 1 of FIG. 8, the dampers 321, 233, 611 are opened and the dampers 311, 234, 621 are closed in step S11 of FIG. Further, the oxidant is ejected from the first oxidant nozzle 41 and the second oxidant nozzle 42, and the modifier is ejected from the first modifier nozzle 51. Thereby, precipitates increase in the second filling space 22 and precipitates decrease in the first filling space 21. Further, the heat generated from the pyrolysis gas in the second split furnace 292 is used for reforming the precipitates in the first filling space 21. Therefore, the flow rate of the oxidant ejected from the first oxidant nozzle 41 can be reduced, and the amount of oxidant used can be reduced.

  In step S12 in which the pyrolysis gas does not flow through the second supply flow path 32, the dampers 311, 234, and 621 are opened, and the dampers 321, 233, and 611 are closed. Further, the oxidant is ejected from the first oxidant nozzle 41 and the second oxidant nozzle 42, and the modifier is ejected from the second modifier nozzle 52. Thereby, precipitates increase in the first filling space 21 and precipitates decrease in the second filling space 22. Further, the heat generated from the pyrolysis gas in the first split furnace 291 is used for reforming the precipitate in the second filling space 22. Therefore, the flow rate of the oxidant ejected from the second oxidant nozzle 42 can be reduced, and the amount of oxidant used can be reduced.

  In addition, what connected the 1st division furnace 291 and the 2nd division furnace 292 in series via one auxiliary flow path is replaced with the furnace main body 2 of FIG. 6, and is oxidized at the same position as FIG. 6. By disposing the agent nozzles 40 to 42 and the modifier nozzles 50 to 52, the heat generated in one of the split furnaces may be used for reforming the precipitate in the other split furnace.

  Various modifications are possible in the gasification system 8 and the gas reforming furnace 1.

  In the gas reforming furnace 1, three or more filling spaces may be provided. In this case, supply flow paths are individually connected to the three or more filling spaces. Then, the flow rate of the pyrolysis gas flowing through the supply channel connected to the one filling space is made smaller than that of the other supply channel, so that the precipitate in the one filling space is reduced, and the other A state is formed in which precipitates in the filling space increase.

  For example, in the gas reforming furnace 1 of FIG. 1, the holding members 211 and 221 may be omitted, and the filler may be held at the bottom of the furnace body 2. In this case, one of the space filled with the filling material divided into two in the gas flow direction is the first filling space 21 and the other is the second filling space 22. In addition, in the furnace bodies 2 and 2a in which the gas flow direction is, for example, the horizontal direction, the filling spaces 21 and 22 may be formed by filling a filler between two holding members adjacent to each other.

  The filler may be formed of a metal or a mineral, and does not necessarily need to be a porous body if a surface area capable of depositing a sufficient amount of precipitate is obtained. Depending on the design of the gas reforming furnace 1, a metal catalyst that contributes to the decomposition of tar may be used as the filler. The shape of the filler may be a columnar shape or a granular shape other than the spherical shape.

  In the above embodiment, the first filling space 21 and the second filling space 22 are heated by the supply of the oxidant to the pyrolysis gas, but the first filling space 21 and the second filling space 22 are heated by the heater. May be. In this case, in the filling space heating unit 4, a heater or a heat exchanger, or a nozzle for ejecting high-temperature gas is provided as the heater. In the filling space heating unit 4, the first filling space 21 and the second filling space 22 may be heated using a heater and an oxidizer nozzle in combination.

  For example, an oxidant nozzle and a modifier nozzle may be provided in the common flow path 30 (see FIG. 1), and the oxidant and the modifier may be supplied to the first filling space 21 and the second filling space 22. On the other hand, from the viewpoint of efficiently using the oxidant, the filling space heating unit 4 has a plurality of oxidant nozzles and can individually supply the oxidant to the first filling space 21 and the second filling space 22. It is preferable. Similarly, from the viewpoint of efficiently using the modifier, the modifier supply unit 5 has a plurality of modifier nozzles, and the modifiers are individually provided in the first filling space 21 and the second filling space 22. It is preferable that it can be supplied. The oxidant nozzle and the modifier nozzle may be provided in the filling spaces 21 and 22 or in the supply flow paths 31 and 32.

  The pyrolysis gas (that is, the reformed gas) reformed by the gas reforming furnace 1 may be used in a gas turbine or a fuel cell (such as a solid oxide fuel cell (SOFC)). In addition, the reformed gas may be used as a fuel gas for various purposes, and may further be used as a liquid fuel by converting it into a liquid. The process of the gas reforming furnace 1 and FIG. 2 can also be regarded as a fuel gas generation device and a fuel gas generation process.

  The configurations in the above-described embodiments and modifications may be combined as appropriate as long as they do not contradict each other.

DESCRIPTION OF SYMBOLS 1 Gas reforming furnace 2,2a Furnace main body 3 Supply adjustment part 4 Filling space heating part 5 Modifier supply part 10 Control part 21 1st filling space 22 2nd filling space 31 1st supply flow path 32 2nd supply flow path 81 Gasification furnace 200 Main body flow path S11, S12 Step

Claims (6)

A gas reforming furnace for reforming pyrolysis gas supplied from a gasification furnace,
A furnace body having a first filling space and a second filling space filled with a filling;
A first supply passage and a second supply passage connected to the first filling space and the second filling space, respectively, and the pyrolysis gas is passed through the first supply passage and the second supply passage; A supply adjusting unit that supplies the first filling space and the second filling space and is capable of changing a flow rate of the pyrolysis gas flowing through each supply flow path;
A filling space heating unit for heating the first filling space and the second filling space by supplying an oxidant to the pyrolysis gas or by a heater;
In the first filling space and the second filling space, a reformer is supplied to the precipitate deposited on the filler from the pyrolysis gas, thereby reforming the deposit into a fuel gas. A material supply section;
By controlling the supply adjusting unit, the state in which the flow rate of the pyrolysis gas flowing through the first supply flow path is smaller than that of the second supply flow path, and the pyrolysis flowing through the second supply flow path A control unit that switches between other states in which the flow rate of the gas is smaller than the first supply flow path;
With
In the one state, the precipitate in the first filling space decreases and the precipitate in the second filling space increases, and in the other state, the precipitate in the second filling space increases. A gas reforming furnace that decreases and increases the precipitates in the first filling space. The gas reforming furnace according to claim 1,
The modifier supply unit can individually supply the modifier to the first filling space and the second filling space;
The flow rate of the modifier supplied to the second filling space in the one state is smaller than that of the other state, and the flow rate of the modifier supplied to the first filling space in the other state. However, the gas reforming furnace is smaller than the one state. A gas reforming furnace according to claim 1 or 2, wherein
The gas reforming furnace, wherein the filler is a porous body. A gas reforming furnace according to any one of claims 1 to 3,
The gas reforming furnace, wherein the filling space heating unit can individually supply the oxidant to the first filling space and the second filling space. A gas reforming furnace according to claim 4, wherein
The furnace body has a body flow path through which the pyrolysis gas flows;
An upstream space in the main body channel includes the first filling space, and a downstream space includes the second filling space,
In the other state, the gas reforming furnace characterized in that a flow rate of the oxidant supplied to the second filling space is smaller than that in the one state. A pyrolysis gas reforming method in a gas reforming furnace,
The gas reforming furnace is
A furnace body having a first filling space and a second filling space filled with a filling;
A first supply channel and a second supply channel connected to the first filling space and the second filling space, respectively, and pyrolysis gas supplied from a gasification furnace is supplied to the first supply channel and the first supply channel. A supply adjustment unit that supplies the first filling space and the second filling space via two supply passages and is capable of changing the flow rate of the pyrolysis gas flowing through each supply passage;
A filling space heating unit for heating the first filling space and the second filling space by supplying an oxidant to the pyrolysis gas or by a heater;
In the first filling space and the second filling space, a reformer is supplied to the precipitate deposited on the filler from the pyrolysis gas, thereby reforming the deposit into a fuel gas. A material supply section;
With
The pyrolysis gas reforming method comprises:
a) forming a state where the flow rate of the pyrolysis gas flowing through the first supply flow path is smaller than that of the second supply flow path using the supply adjusting unit;
b) forming another state in which the flow rate of the pyrolysis gas flowing through the second supply flow path is smaller than that of the first supply flow path using the supply adjusting unit;
With
In the one state, the precipitate in the first filling space decreases and the precipitate in the second filling space increases, and in the other state, the precipitate in the second filling space increases. A pyrolysis gas reforming method characterized by decreasing and increasing the precipitate in the first filling space.