JP5261931B2 - Fluidized bed gasification method and apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To increase production of high-quality gasified gas in a fluidized bed gasification furnace wherein a chamber to which an organic raw material is fed to produce pyrolysis gas containing tar through a pyrolytic reaction is separated from a chamber to which pyrolysis residue produced through the pyrolytic reaction is introduced to produce the gasified gas. <P>SOLUTION: The fluidized bed gasification furnace 2 is composed of a first chamber 31 and a second chamber 32. The organic raw material M is fed to the first chamber 31 and subjected to the pyrolytic reaction in the first chamber 31 to produce the pyrolysis gas 55. The thermolysis residue M' produced through the pyrolytic reaction of the organic raw material M in the first chamber 31 is introduced into a fluidized bed 16 in the second chamber 32 to produce the gasified gas 35 through a gasification reaction. <P>COPYRIGHT: (C)2008,JPO&amp;INPIT

Description

  The present invention relates to a fluidized bed gasification method and apparatus for gasifying an organic material.

  It has a fluidized bed combustion furnace and a fluidized bed gasification furnace, gasifies organic materials such as biomass and coal in the fluidized bed gasification furnace, and burns the char generated in the fluidized bed gasification furnace in the fluidized bed combustion furnace. There has been proposed a fluidized bed gasification apparatus that heats a fluidized medium and returns the heated fluidized medium to the fluidized bed gasification furnace (see Patent Document 1).

  FIG. 11 shows the fluidized bed gasification apparatus of the above-mentioned Patent Document 1. In the figure, reference numeral 1 denotes char (gasification unreacted residue) generated when the organic material M is gasified in the fluidized bed gasification furnace 2. And a fluidized medium are introduced into the lower part of the fluidized bed combustion furnace. The fluidized bed combustion furnace 1 flows the char and the fluidized medium at high speed with the air supplied to the lower wind box 3 by the air pipe 4. The fluidized medium is heated by combusting the char while ascending. Reference numeral 5 denotes an auxiliary fuel pipe for supplying auxiliary fuel to the fluidized bed of the fluidized bed combustion furnace 1, and reference numeral 6 denotes a heat exchanger for heat recovery provided in the upper part of the fluidized bed combustion furnace 1.

  The upper part of the fluidized bed combustion furnace 1 is connected to a separator 8 made of a cyclone via a transfer pipe 7, and the separator 8 is composed of an outer cylinder 9 and an inner cylinder 10, and the transfer pipe 7 enters the outer cylinder 9. The exhaust gas containing the unburned char and the fluid medium introduced in the tangential direction is centrifuged, the exhaust gas and the ash having a fine particle size are discharged from the inner cylinder 10, and the unburned char and the fluid medium 11 having a coarse particle size are separated from the outer cylinder. 9 is supplied to the lower fluidized bed gasification furnace 2 by a downcomer 12 connected to 9.

  The fluidized bed gasification furnace 2 includes an introduction unit 13 for introducing the fluidized medium 11 separated by the separator 8, and a gasification unit for gasifying the organic material M supplied from the material supply line 14 with the heat of the fluidized medium 11. 15, the introduction part 13 and the gasification part 15 are communicated in the fluidized bed 16, the communication part 17 for transferring the fluid medium 11 from the introduction part 13 to the gasification part 15, the introduction part 13, the communication part 17 and the gas The fluidized bed 16 is formed by supplying the box portion 18 with water vapor as a gasifying agent via a water vapor supply line 19. In FIG. 11, the introduction unit 13 and the gasification unit 15 are separated by the communication unit 17 because the pressure is increased due to the gasification of the organic material M in the gasification unit 15. This is to prevent the fluid medium 11 in 2 from flowing back to the separator 8.

In the gasification unit 15, the organic material is heated by the fluidized bed 16 to remove moisture (water vapor), and a pyrolysis reaction (a component containing hydrocarbon CH such as methane CH ₄ and tar, other carbon monoxide CO, carbon dioxide) The generation of pyrolysis gases such as carbon CO ₂ and hydrogen H ₂ ) and gasification reaction (in the case of steam gasification, the generation of gasification gas mainly composed of carbon monoxide CO and hydrogen H ₂ ). The product gas 20 is led to the recovery device 22 by the discharge pipe 21 and the fine powder 23 entrained in the product gas 20 is removed, and then the product gas 20 is led out from the inner pipe 24, for example, after being pressurized. Supplied to a gas turbine or the like.

Further, the char that has not been gasified in the gasification section 15 and a part of the fluidized medium are circulated from the overflow pipe 25 to the fluidized bed combustion furnace 1 and fluidized and burned again.
JP 2005-41959 A

  However, in the conventional fluidized bed gasifier, the organic material M is supplied to the gasification section 15 of the fluidized bed gasification furnace 2 and gasified by fluidized heating as shown in FIG. The raw material M stays on the fluidized bed 16 of the gasification unit 15 for a while and the pyrolysis reaction and the gasification reaction proceed simultaneously. However, the generated gas generated in the gasification unit 15 immediately enters the gas phase above the fluidized bed 16. Since the product gas 20 is released, the product gas 20 is not further subjected to a thermal history due to contact with the fluidized medium 11 inside the fluidized bed 16. Note that a large amount of tar is generated at the initial stage of gasifying the organic material M, but this tar is not subjected to the thermal history of the fluidized medium 11 and is therefore not decomposed from the discharge pipe 21 together with the generated gas 20. Will be discharged.

  Here, there is a research report that tar generated by thermal decomposition reaction of organic raw materials has an action to inhibit water gasification reaction (carbon + water vapor → carbon monoxide + hydrogen) (Hayashi et al. Fuel. 2005; Volume84: p1612).

  In this way, when a large amount of tar is generated in the gasification section 15, the gasification reaction is inhibited, so that the reaction progresses slowly and the amount of gas generated decreases, and the reaction time is kept long. In order to increase the amount of gas generated, there is a problem that it is necessary to increase the volume of the gasification section 15 and thus the fluidized bed gasification furnace 2.

  Furthermore, since the tar generated in the gasification unit 15 is discharged without being gasified, the gasification rate in the gasification unit 15 is further reduced, and the generated gas 20 taken out from the recovery unit 22 is removed by tar. There exists a problem that the load of the tar removal apparatus for leading to an apparatus and removing tar increases.

  On the other hand, as one method for reducing the generation of the tar, it is conceivable to supply the organic material M directly into the fluidized bed 16 using a screw feeder or the like. According to this method, since the contact between the organic material M and the fluid medium is enhanced, the tar can be decomposed, and thus an effect of reducing the problem due to the tar being discharged can be expected. However, when the organic raw material M is directly supplied to the inside of the fluidized bed 16 by the screw feeder in this way, the raw material is thermally decomposed in the screw feeder, and the raw material is screwed by inflow / condensation of water vapor. There is a problem of solidifying in the feeder, and for this reason, there is a problem that the screw feeder cannot be stably operated.

  The present invention has been made in view of the above-described conventional problems. A fluidized bed gasification furnace is provided with a chamber in which an organic raw material is supplied and a pyrolysis gas containing tar is generated by a pyrolysis reaction, and a pyrolysis reaction. An object of the present invention is to provide a fluidized bed gasification method and apparatus capable of enhancing the production of high-quality gasification gas by introducing the generated pyrolysis residue into a chamber for generating gasification gas. .

The invention of claim 1, the the resulting char during the gasification of organic material and the fluidized medium char while flow is introduced into the fluidized bed combustion furnace is combusted to heat the fluidized medium, from the fluidized bed combustion furnace The fluidized medium is separated by a separator, and the separated fluidized medium is introduced into a fluidized bed gasification furnace to form a fluidized bed, and the organic material is supplied to the fluidized bed gasification furnace and generated by gasification of the organic material. to eject the gas, the a in which the fluidized-bed gasification method so as to CFB generated char during gasification of organic material in the gasification furnace and a part of the fluidized medium in the fluidized bed combustion furnace ,
The fluidized bed gasification furnace is composed of a first chamber and a second chamber, the fluid medium from the separator is distributed and supplied to the first chamber and the second chamber, and the organic material raw material is supplied to the first chamber. the supplied by thermal decomposition reaction to generate pyrolysis gases, introduced to the gasification reaction the first chamber pyrolysis residue organic raw material is generated by thermal decomposition reaction in the interior of the fluidized bed of the second chamber The gasification gas is generated by the above, and the pressure in the first chamber is controlled by adjusting the amount of the pyrolysis gas generated in the first chamber to introduce the pyrolysis residue in the first chamber into the second chamber. It is the fluidized bed gasification method characterized by these.

  The invention according to claim 2 is characterized in that the pyrolysis gas generated by the pyrolysis reaction of the organic material in the first chamber is supplied to the fluidized bed combustion furnace to be used for heating the fluidized medium. It is a fluidized bed gasification method.

According to a third aspect of the present invention, a CH reference value generated by performing a test in advance for measuring a generated amount of a hydrocarbon CH-containing component that is generated when the unit amount of the organic raw material is fluidly heated is obtained. Measuring the amount of hydrocarbon components produced by the thermal decomposition reaction in the chamber to obtain a CH measurement value, measuring the amount of the organic raw material supplied to the first chamber to obtain the raw material supply amount, Matching the CH measurement value with the CH prediction value obtained from the raw material supply amount and the CH reference value is used as an indicator of the end of the thermal decomposition reaction in the first chamber, and the CH measurement value is matched with the CH prediction value. 2. The fluidized bed gasification method according to claim 1 , wherein the pyrolysis residue is introduced into the second chamber by controlling the pressure in the one chamber.

A fourth aspect of the present invention, according to any one of claims 1-3, characterized in that for controlling the temperature of the first chamber by adjusting the supply amount of the first chamber to supply fluid medium It is a fluidized bed gasification method.

The invention of claim 5, measures the tar produced by the gasification reaction in the second chamber to obtain a tar measurement value, thermal decomposition of the said tar measurement value matches the tar setpoint in the first chamber 5. The fluidized bed gasification method according to claim 4 , wherein the temperature of the first chamber is controlled so that the tar measurement value coincides with the tar set value as an indicator of completion of the reaction.

According to the sixth aspect of the present invention, the char generated during the gasification of the organic material and the fluidized medium are introduced into the fluidized bed combustion furnace to cause the char to burn while heating the fluidized medium. The fluidized medium is separated by a separator, and the separated fluidized medium is introduced into a fluidized bed gasification furnace to form a fluidized bed, and the organic material is supplied to the fluidized bed gasification furnace and generated by gasification of the organic material. A fluidized bed gasification apparatus that takes out gas and circulates a part of char and fluidized medium generated during gasification of an organic raw material in the fluidized bed gasification furnace to the fluidized bed combustion furnace,
Said fluidized bed gasification furnace, provided with a material supply device and the first chamber for performing a thermal decomposition reaction of the organic raw material, the pyrolysis residue produced by pyrolysis reaction of organic raw material in the first chamber in the interior of the fluidized bed And a second chamber for introducing a gasification reaction and controlling the temperature of the first chamber by distributing and supplying the fluid medium from the separator to the first chamber and the second chamber. A fluidized bed gasifier comprising temperature control means and pressure control means for controlling the pressure in the first chamber by adjusting the extraction of the pyrolysis gas generated in the first chamber.

The invention of claim 7, claim 6, characterized in that organic material in the first chamber is a pyrolysis gas generated by thermal decomposition reaction with the pyrolysis gas pipe for supplying the fluidized bed combustion furnace This is a fluidized bed gasifier.

The invention of claim 8, wherein the raw material supply device, fluidized bed gasification according to claim 6 or 7, characterized in that as provided to supply organic raw material in the upper space of the first chamber of the fluidized bed Device.

The invention of claim 9, wherein the temperature control means includes a dispensing device for supplying and distributing the fluid medium from the separator into the first chamber and a second chamber, and a thermometer for measuring the temperature of the first chamber, 2. A fluid medium controller for controlling a supply amount of a fluid medium supplied to the first chamber and the second chamber by the distributor so that a temperature detected by the thermometer becomes a set temperature. 6-8 is a fluidized bed gasifier according to any one.

The invention of claim 10, wherein the pressure control means, wherein a first chamber pressure gauge for detecting the pressure of the pyrolysis gas generated in the first chamber so that the detected pressure of the pressure gauge is set pressure a fluidized bed gasifier according to any one of claims 6-9, characterized in that it consists of a gas take-off controller for adjusting the extraction quantity.

The invention of claim 11, and CH reference value generation amount obtained in advance the hydrocarbon components produced upon flow heating unit amount of the organic raw material,
CH measurement value from a CH measuring instrument that measures the amount of hydrocarbon CH-containing component produced by the pyrolysis reaction in the first chamber;
Input a raw material supply amount from a raw material supply amount detector that measures the supply amount of the organic raw material supplied to the first chamber by the raw material supply device ,
Claim 6 wherein the CH measurement value, characterized by comprising a CH corrector for correcting the pressure by the pressure control means so as to coincide with CH predictive value obtained from said CH reference value and the material feed amount ~ Fluidized bed gasifier according to any one of ~ 10 .

The invention of claim 12 inputs the obtained Ru tar instrument tar measurement value by measuring the amount of generation of tar generated by the gasification reaction in the second chamber, the tar measurements from the tar Instrument The fluidized bed gasification according to any one of claims 6 to 11 , further comprising a tar corrector that corrects a temperature by the temperature control means so that the tar measurement value becomes a tar set value. Device.

  According to the fluidized bed gasification method and apparatus of the first to thirteenth aspects of the present invention, the organic material is supplied to the first chamber to generate the pyrolysis gas by the pyrolysis reaction of the organic material, By adjusting the amount of the pyrolysis gas produced in the first chamber and controlling the pressure in the first chamber, the pyrolysis residue produced in the pyrolysis reaction is introduced into the fluidized bed in the second chamber, Since gasification gas is generated by gasification reaction in the chamber, tar is generated in the second chamber by introducing the pyrolysis residue after the pyrolysis reaction in the first chamber into the second chamber. As a result, the gasification reaction in the second chamber can be effectively enhanced and the amount of gasification gas generated can be increased. There is an effect that can be miniaturized.

  Furthermore, since the pyrolysis gas generated in the first chamber is supplied to the fluidized bed combustion furnace to be used for heating the fluidized medium, char (gasification unreacted residue) is combusted in the fluidized bed combustion furnace as in the past. Compared to the case where the fluidized medium is heated and heated only with heat, the amount of char combustion in the fluidized bed combustion furnace can be reduced because the combustion heat of the pyrolysis gas is added. Since the gasification amount in the fluidized bed gasification furnace can be increased, the production amount of gasification gas is increased.

In addition, the gasification gas generated by gasifying the pyrolysis residue in the second chamber has less tar and methane CH _{4 and the} like, and the ratio of carbon monoxide CO and hydrogen H ₂ is larger than the conventional gas. There is an effect that it is possible to generate a high-quality gasification gas having a high utility value as a gas for synthesis of gasification gas or a liquid fuel.

  Moreover, since the tar contained in the gasification gas decreases, there is an effect that the post-treatment load for removing the tar can also be reduced.

  Embodiments of the present invention will be described below with reference to the accompanying drawings.

  FIG. 1 is a flowchart showing an example of an embodiment of the present invention. The basic configuration is substantially the same as that in FIG. 11, and the same parts as those in FIG. Hereinafter, only the features of the present invention will be described in detail.

  As shown in FIGS. 1 and 2, the fluidized bed gasification furnace 2 in which the fluidized bed 16 is formed has the first chamber 31 and the first chamber 31 separated by a separation wall 30 extending from the inside upper part to the inside of the fluidized bed 16. It is divided into two chambers 32. At this time, the first chamber 31 and the first chamber 31 pass through the inside of the fluidized bed 16 between the box portion 18 for introducing a gasifying agent such as water vapor and air into the lower portion of the fluidized bed gasification furnace 2 and the lower end of the separation wall 30. A communication portion 33 is formed so as to communicate with the two chambers 32.

  The first chamber 31 is provided with a material supply device 34 such as a screw feeder for supplying the organic material M to the space above the fluidized bed 16.

In the above configuration, the organic raw material M supplied to the first chamber 31 by the raw material supply device 34 is heated by the fluid medium of the fluidized bed 16 in the first chamber 31 to remove moisture, and further undergo a thermal decomposition reaction. Thus, components containing hydrocarbon CH such as methane CH ₄ and tar are generated, and other pyrolysis gas containing carbon monoxide CO, carbon dioxide CO ₂ , hydrogen H _{2 and the} like is generated.

Further, the thermal decomposition residue M ′ generated during the thermal decomposition reaction of the organic raw material M in the first chamber 31 passes through the fluidized bed 16 so as to dive through the communication portion 33 at the lower part of the separation wall 30 as indicated by a white arrow. When the gasification reaction is caused by heating by the fluidized bed 16 of the second chamber 32 and the gasifying agent is water vapor, the gasification mainly includes carbon monoxide CO and hydrogen H ₂ . Gas is generated. At this time, the gasified gas 35 generated in the second chamber 32 is taken out by the gasified gas pipe 36 and guided to the solid content removing device 37 made of a cyclone or the like to remove the solid content. The gasification gas take-out fan 39 is led to the gas.

  The first chamber 31 and the second chamber 32 can be formed by a method other than the method of forming the separation wall 30 in the fluidized bed gasification furnace 2 as described above. For example, as shown in FIG. 3, the first chamber 31 and the second chamber 32 configured separately are connected by a communication path 40 at a lower position in the fluidized bed 16 and are generated by a thermal decomposition reaction in the first chamber 31. The thermally decomposed residue M ′ and the fluidized medium are supplied to the second chamber 32 through the communication passage 40, or the first chamber 31 and the second chamber 32 configured separately are provided as shown in FIG. The thermal decomposition residue M ′ generated by the thermal decomposition reaction in the first chamber 31 and the fluidized medium are supplied into the fluidized bed 16 of the second chamber 32 by the overflow pipe 41, or as shown in FIG. The first chamber 31 and the second chamber 32 may be formed by providing the partition wall 42 in the bed gasification furnace 2 and providing the communication portion 43 in the lower part of the fluidized bed 16.

  Here, the partition wall 30 and the partition wall 42 may be a metal plate, but in order to further improve the durability, a water-cooled wall constituted by a water-cooled pipe or a structure to which a refractory brick is further applied can be used. .

  The exhaust gas containing the fluidized medium and the unburned char from the fluidized bed combustion furnace 1 of FIG. 1 is guided to the separator 8 made of a cyclone by the transfer pipe 7 to separate the exhaust gas, and the exhaust gas passes through the exhaust gas treatment device 44. It is guided to the exhaust gas fan 45.

  As described above, the first chamber 31 performs a thermal decomposition reaction, and the second chamber 32 performs a gasification reaction of the thermal decomposition residue M ′ generated by the thermal decomposition reaction in the first chamber 31. First, it is necessary to know that the thermal decomposition reaction has been completed in the first chamber 31. For this reason, the present inventors can know that the thermal decomposition reaction has been completed in the first chamber 31 and serve as an index. An experiment for finding the object was performed using the test apparatus shown in FIG.

As shown in FIG. 6, a fluidized bed was formed by supplying water vapor c as a gasifying agent at a supply rate of 3.0 g / min to the lower part of a container b into which sand a was inserted, and the container b was provided outside. In a state where the sand layer temperature is heated to 830 ° C. in the electric furnace d, 1.8 g of coal e (brown coal) (moisture 35%) is charged into the inside of the vessel b at a time (not continuous charging) and gas The integrated amount of each gas component of hydrogen H _{2 of the} gas f generated at that time, carbon dioxide CO ₂ , carbon monoxide CO and hydrocarbon CH (mol-C / kg) was measured. The results are shown in FIG.

From the results shown in FIG. 7, hydrogen H ₂ , carbon dioxide CO ₂ , and carbon monoxide CO increased in production amount with the lapse of time after charging coal e, whereas hydrocarbon CH represents coal e. It was found that the generation was completed in about 1 minute after the addition and was not generated after that. As described above, since the generation of the hydrocarbon CH is completed in a short time of about 1 minute from the input of the coal e, the time point when the generation of the hydrocarbon CH is completed is defined as “when the thermal decomposition reaction is completed”. Thought. It was also found that when the production of the hydrocarbon CH was completed, the moisture was dried and the generation of tar was almost finished.

  Therefore, the CH reference value, which is the amount of hydrocarbon CH produced per coal unit, can be obtained from the results of the experiment.

  Therefore, when the supply amount of the organic raw material M continuously supplied to the first chamber 31 by the raw material supply device 34 is measured and multiplied by the CH reference value, the hydrocarbon CH produced in the first chamber 31 is calculated. The production amount can be estimated. Therefore, if the amount of hydrocarbon CH produced in the first chamber 31 is measured and the amount of hydrocarbon CH produced is adjusted so that this CH measurement value matches the estimated CH value, It was found that the thermal decomposition reaction can be maintained in a completed state.

  As a configuration for adjusting the amount of hydrocarbon CH produced in the first chamber 31, the temperature control means 100 for controlling the temperature of the first chamber 31 and the pressure in the first chamber 31 are controlled. Pressure control means 200 for controlling the residence time until the thermal decomposition residue M ′ generated in the first chamber 31 is guided to the second chamber 32.

  The temperature control means 100 is configured as follows.

  As shown in FIGS. 1 and 2, a distribution device 46 is provided in the downcomer pipe 12 where the flowing medium 11 containing unburned char separated by the separator 8 descends, and distribution pipes 47 and 48 are connected to the distribution device 46. Thus, the fluid medium 11 of the downcomer pipe 12 is distributed and supplied to the first chamber 31 and the second chamber 32.

Further, wherein the first chamber 31, a thermometer 49 for detecting the temperature of the upper inner first chamber 31 is installed, the dispensing device so that the detected temperature of the temperature meter 49 becomes a predetermined set temperature T ₁ of A fluid medium controller 50 is provided for controlling the supply amount of the fluid medium 11 to be supplied to the first chamber 31 and the second chamber 32 via the distribution pipes 47 and 48 by 46. Here, the set temperature T ₁ set in the fluid medium controller 50 is, for example, supplied to the first chamber 31 by the fluid medium 11 that is heated and lowered to around 900 ° C. This is the temperature at which drying and thermal decomposition reactions occur. That is, the setting temperatures _{T 1} is to be set to, for example, a second chamber of a temperature lower than about 830 ° C. the temperature at the time of the gasification reaction at 32 600 to 800 ° C. before and after (e.g., 780 ° C.).

  As the distribution device 46, as shown in FIG. 8, a control damper 51 is provided in the downcomer 12 so that the damper angle is controlled by a signal from the fluid medium controller 50. As shown in FIG. 9, bubbling devices 52a and 52b are provided at the inner bottoms of the horizontal portions of the distribution pipes 47 and 48 that branch horizontally from the downcomer 12, and the air is supplied to the bubbling devices 52a and 52b. It is possible to use one in which the opening degree of each of the flow rate adjusting valves 54a, 54b provided in the air pipes 53a, 53b is controlled by a signal from the fluid medium controller 50. In the case of FIG. 9, when the ejection of air from the bubbling devices 52a and 52b is stopped, the supply of the fluid medium 11 to the corresponding distribution pipes 47 and 48 is stopped, and when the air ejection is increased, the supply amount of the fluid medium 11 is increased. Thus, the distribution of the fluid medium 11 can be adjusted.

  The pressure control means 200 is configured as follows.

A pyrolysis gas pipe 56 for taking out the pyrolysis gas 55 generated in the first chamber 31 is connected to the upper portion of the first chamber 31 in FIG. The pyrolysis gas 55 taken out from the pyrolysis gas pipe 56 may be supplied to various places of use, or may be used by mixing with the gasification gas 35 from the second chamber 32, or discarded. May be. In the form of FIG. 1, the pyrolysis gas pipe 56 is supplied to the fluidized bed combustion furnace 1 via an ejector 57. An air fan 59 for supplying air is connected to the ejector 57 via an air pipe 58. By supplying air to the ejector 57 by the air fan 59, the ejector 57 flows together with the pyrolysis gas 55 of the pyrolysis gas pipe 56. It can be supplied to the layer combustion furnace 1. Further, the first chamber 31, a pressure gauge 60 for detecting the pressure in the first chamber 31 is provided, the air fan 59 so that the detected pressure of the pressure gauge 60 is maintained at a predetermined set pressure P ₁ A gas extraction amount controller 61 is provided which controls and adjusts the amount of pyrolysis gas 55 extracted from the first chamber 31 by the ejector 57 to control the pressure in the first chamber 31.

  In FIG. 1, as described above, the control of pressure by the pressure control means 200 is corrected using the hydrocarbon component (CH) generated in the first chamber 31 as an index.

In other words, a CH measuring device 62 for measuring the amount of hydrocarbon CH-containing components produced by the thermal decomposition reaction in the first chamber 31 is provided, and the supply of the organic raw material M supplied to the first chamber 31 by the raw material supply device 34 A raw material supply amount detector 63 for measuring the amount is provided, a CH measurement value 64 from the CH measuring device 62, a raw material supply amount 65 from the raw material supply amount detector 63, and a CH reference value 66 obtained by the experiment. Is input to the CH corrector 67. The CH corrector 67 obtains the CH predicted value X by multiplying the raw material supply amount 65 and the CH reference value 66, and the gas extraction amount controller 61 so that the CH measurement value 64 matches the CH predicted value X. The control signal 68 is sent to the pressure control means 200 to correct the pressure control by the pressure control means 200. That is, when the CH measurement value 64 is lower than the CH prediction value X, the residence time of the organic raw material M in the first chamber 31 is short, so the set pressure P ₁ of the gas extraction amount controller 61 is lowered. Thus, the amount of air supplied to the ejector 57 by the air fan 59 is reduced to reduce the amount of the pyrolysis gas 55 supplied from the first chamber 31 to the fluidized bed combustion furnace 1. As a result, the pressure in the first chamber 31 is lowered and the residence time of the organic raw material M in the first chamber 31 is maintained for a long time, whereby the thermal decomposition reaction in the first chamber 31 is completed.

  In the above embodiment, the case where the pyrolysis gas 55 in the first chamber 31 is supplied to the fluidized bed combustion furnace 1 by the ejector 57 and the air fan 59 has been shown. However, an extraction fan (not shown) is installed in the pyrolysis gas pipe 56. The cracking gas 55 is supplied to the fluidized bed combustion furnace 1 by the take-out fan, or the cracking gas 55 is supplied to another utilization place, or mixed with the gasified gas 35 from the second chamber 32. In this case, the gas extraction amount controller 61 and the CH corrector 67 are provided to control the pressure in the first chamber 31. can do.

  The operation of the embodiment shown in FIG. 1 will be described.

In a state where a fluidizing bed 16 is formed by supplying a gasifying agent such as water vapor or air to the box portion 18 at the bottom of the fluidized bed gasification furnace 2, the organic material M is quantitatively supplied to the first chamber 31 by the material supply device 34. . At this time, the detected temperature from the thermometer 49 that detects the temperature inside the first chamber 31 is input to the fluid medium controller 50, and the fluid medium controller 50 receives the first chamber 31 by the thermometer 49. The first and second chambers 31 and 32 are adjusted via distribution pipes 47 and 48 by adjusting the distributor 46 so that the detected temperature of the water reaches a set temperature T ₁ (for example, 780 ° C.) suitable for the thermal decomposition of the organic material M. The supply amount of the fluid medium 11 to be distributed to each other is controlled.

Furthermore, the detected pressure from the pressure gauge 60 that detects the pressure inside the first chamber 31 is input to the gas extraction amount controller 61, and the gas extraction amount controller 61 detects the pressure detected by the pressure gauge 60. The amount of air sent to the ejector 57 is adjusted by the air fan 59 so as to maintain a set pressure P ₁ set so as to have a residence time suitable for the organic material M to be thermally decomposed in the first chamber 31. The amount of the pyrolysis gas 55 led from the first chamber 31 to the fluidized bed combustion furnace 1 is controlled.

The temperature of the first chamber 31 is controlled to the set temperature T ₁ by the fluid medium controller 50 of the temperature control means 100, and the pressure of the first chamber 31 is set to the set pressure P ₁ by the gas extraction amount controller 61 of the pressure control means 200. As a result, the organic raw material M supplied to the first chamber 31 undergoes a pyrolysis reaction by adjusting the residence time in the first chamber 31, and the pyrolysis generated by the pyrolysis reaction. The gas 55 is supplied to the fluidized bed combustion furnace 1 by the ejector 57, and the pyrolysis residue M ′ generated by the pyrolysis reaction is embedded in the fluidized bed 16 so as to dive through the communication portion 33 below the separation wall 30 as indicated by a white arrow. It is led to the second chamber 32 through.

  In the above, when the thermal decomposition reaction is not completed in the first chamber 31, there is a problem that tar generated in the second chamber 32 increases due to the thermal decomposition reaction occurring in the second chamber 32.

  However, as shown in FIG. 1, the CH measurement value 64 from the CH measuring device 62 that measures the amount of hydrocarbon CH produced in the first chamber 31 and the raw material supply from the raw material supply amount detector 63. The amount 65 and the CH reference value 66 obtained by the experiment are input to the CH corrector 67. The CH corrector 67 multiplies the raw material supply amount 65 and the CH reference value 66 to predict the CH. A value X is obtained, and the control of the pressure by the pressure control means 200 is corrected by sending a control signal 68 to the gas extraction amount controller 61 so that the CH measurement value 64 matches the CH prediction value X.

Therefore, when the CH measurement value 64 is lower than the CH prediction value X, the residence time of the organic raw material M in the first chamber 31 is short, so that the set pressure P ₁ of the gas removal amount controller 61 is corrected to be low. Thus, by reducing the amount of air supplied to the ejector 57 by the air fan 59 and reducing the amount of pyrolysis gas 55 supplied from the first chamber 31 to the fluidized bed combustion furnace 1, the first chamber 31 is reduced. Reduce the pressure. Thereby, the residence time of the organic raw material M in the first chamber 31 is maintained for a long time, so that the thermal decomposition reaction in the first chamber 31 ends.

  As described above, the organic material M is supplied to the first chamber 31 to generate the pyrolysis gas 55 by the pyrolysis reaction of the organic material M, and the generated pyrolysis gas 55 is supplied to the fluidized bed combustion furnace 1 to flow. At this time, the pyrolysis residue M ′ generated by the pyrolysis reaction is adjusted by adjusting the supply amount of the pyrolysis gas 55 supplied to the fluidized bed combustion furnace 1 and controlling the pressure in the first chamber 31. Is introduced into the fluidized bed 16 of the second chamber 32, and the gasification gas 35 is generated by the gasification reaction in the second chamber 32, so that after the thermal decomposition reaction in the first chamber 31 is completed. Since the pyrolysis residue M ′ is introduced into the second chamber 32, the amount of tar generated in the second chamber 32 is suppressed as much as possible, and thus the gasification reaction in the second chamber 32 is effectively performed. The production amount of the gasification gas 35 can be increased, whereby the second 32, by extension it is possible to miniaturize the fluidized bed gasification furnace 2.

  At this time, since the control of the pressure by the pressure control means 200 is corrected by controlling the gas extraction amount controller 61 by the CH corrector 67, it is possible to control the thermal decomposition reaction in the first chamber 31, so that the second In the chamber 32, a high-quality gasified gas 35 having high utility value is generated by the gasification reaction.

  Further, since the pyrolysis gas 55 generated in the first chamber 31 is supplied to the fluidized bed combustion furnace 1 to be used for heating the fluidized medium, the char (gasification unreacted residue) in the fluidized bed combustion furnace is conventionally used. ), The amount of char burned in the fluidized bed combustion furnace 1 can be reduced as compared with the case where the heating temperature of the fluidized medium is heated only with the combustion heat of Since the amount of gasification in the fluidized bed gasification furnace can be increased in anticipation of the reduction in combustion, the amount of gasified gas 35 produced increases. Therefore, the char that is not used for combustion is led again to the second chamber 32 and is gasified, so that the amount of gasified gas 35 generated increases.

Further, the gasification gas 35 generated by gasifying the thermal decomposition residue M ′ in the second chamber 32 has less tar and methane CH _{4 and the} like, and the ratio of carbon monoxide CO and hydrogen H ₂ is higher than the conventional gas. Therefore, the utility value of the gasified gas 35 as a gas for synthesizing a chemical raw material or liquid fuel is enhanced.

  Further, since the tar contained in the gasification gas 35 is reduced, the post-treatment load for removing the tar is also reduced.

  FIG. 10 shows another example of an embodiment for carrying out the present invention. In FIG. 10, instead of using the hydrocarbon CH shown in FIG. 1 as an index, the pyrolysis reaction is completed in the first chamber 31 using the amount of tar generated during the gasification reaction in the second chamber 32 as an index. I try to judge what I did. That is, a tar measuring instrument 69 for measuring the amount of tar generated in the gasified gas 35 taken out from the gasification gas pipe 36 is provided, and the tar measurement value 70 from the tar measuring instrument 69 is input to the tar corrector 72. Yes.

When the temperature of the first chamber 31 is maintained at the set temperature T ₁ by the fluid medium controller 50, the tar corrector 72 sends a control signal 73 to the gas removal amount controller 61 and uses the pressure control means 200. By controlling the control of the pressure, the thermal decomposition reaction in the first chamber 31 is controlled to end, and the pressure in the first chamber 31 is held at the set pressure P ₁ by the gas extraction amount controller 61. In this case, it is possible to control the thermal decomposition reaction in the first chamber 31 to be completed by sending a control signal 74 to the fluid medium controller 50 and correcting the temperature control by the temperature control means 100.

  Here, since the tar cannot be measured continuously, the correction of the control by the tar corrector 72 using the tar as an index is intermittent, but also in this method, the thermal decomposition reaction occurs in the first chamber 31. It can be controlled to end.

  Further, in addition to the configuration provided with the CH corrector 67 using the hydrocarbon CH shown in FIG. 1 as an index, the tar corrector 72 using the tar shown in FIG. It becomes possible to control with higher accuracy so that the thermal decomposition reaction in the first chamber 31 is completed.

  Of course, the fluidized bed gasification method and apparatus of the present invention can be used for gasification of various organic raw materials, and various modifications can be made without departing from the scope of the present invention.

It is a flowchart which shows an example of the form which implements this invention. It is detailed explanatory drawing of the fluidized bed gasification furnace part in FIG. It is a schematic side view which shows an example of a structure of the fluidized bed gasification furnace which consists of the 1st chamber and 2nd chamber in this invention. It is a schematic side view which shows the other structural example of the fluidized bed gasification furnace which consists of the 1st chamber and 2nd chamber in this invention. It is a schematic side view which shows the further another structural example of the fluidized bed gasification furnace which consists of the 1st chamber and 2nd chamber in this invention. It is the schematic of the test apparatus used for the experiment for knowing that the thermal decomposition reaction was complete | finished in this invention. It is a diagram which shows the integrated amount of each gas component obtained by experiment by the test apparatus of FIG. It is a side view which shows an example of the distribution apparatus in this invention. It is a side view which shows the other example of the distribution apparatus in this invention. It is a flowchart which shows the other example of the form which implements this invention. It is a side view which shows an example of the conventional fluidized bed gasification apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Fluidized bed combustion furnace 2 Fluidized bed gasifier 8 Separator 11 Fluidized medium 16 Fluidized bed 31 1st chamber 32 2nd chamber 34 Raw material supply apparatus 35 Gasified gas 46 Distributor 49 Thermometer 50 Fluidized medium controller 55 Thermal decomposition Gas 56 Pyrolysis gas pipe 60 Pressure gauge 61 Gas extraction amount controller 62 CH measuring device 63 Raw material supply amount detector 64 CH measurement value 65 Raw material supply amount 66 CH reference value 67 CH corrector 69 Tar measurement device 70 Tar measurement value 72 Tar corrector 100 Temperature control means 200 Pressure control means M Organic material M 'Pyrolysis residue P ₁ Set pressure T ₁ Set temperature X CH Predicted value

Claims (12)

Char and fluid medium generated during gasification of organic materials are introduced into a fluidized bed combustion furnace and heated while the char is burned to heat the fluidized medium, and the fluidized medium from the fluidized bed combustion furnace is separated by a separator. Then, the separated fluidized medium is introduced into a fluidized bed gasification furnace to form a fluidized bed, and an organic material is supplied to the fluidized bed gasification furnace to extract a product gas generated by gasification of the organic material, A fluidized bed gasification method in which a part of char and fluidized medium generated during gasification of an organic raw material in a gasification furnace is circulated to the fluidized bed combustion furnace,
The fluidized bed gasification furnace is composed of a first chamber and a second chamber, the fluid medium from the separator is distributed and supplied to the first chamber and the second chamber, and the organic material raw material is supplied to the first chamber. To generate a pyrolysis gas by a pyrolysis reaction, and introduce a pyrolysis residue generated by a pyrolysis reaction of the organic material in the first chamber into the fluidized bed of the second chamber to perform a gasification reaction. The gasification gas is generated by the above, and the pressure in the first chamber is controlled by adjusting the amount of the pyrolysis gas generated in the first chamber to introduce the pyrolysis residue in the first chamber into the second chamber. A fluidized bed gasification method characterized by the above.   2. The fluidized bed gasification method according to claim 1, wherein a pyrolysis gas generated by a pyrolysis reaction of an organic material in the first chamber is supplied to the fluidized bed combustion furnace to be used for heating the fluidized medium. . A CH reference value generated by conducting a test in advance to measure the amount of hydrocarbon CH-containing component generated when the unit amount of the organic raw material is fluidly heated is obtained, and the thermal decomposition reaction in the first chamber is performed. The amount of generated hydrocarbon components is measured to obtain a CH measurement value, and the amount of the organic raw material supplied to the first chamber is measured to obtain the material supply amount. Matching the predicted CH value obtained from the amount and the CH reference value is used as an indicator of the end of the thermal decomposition reaction in the first chamber, and the pressure in the first chamber is controlled so that the measured CH value matches the predicted CH value. The fluidized bed gasification method according to claim 1 , wherein the pyrolysis residue is introduced into the second chamber.   The fluidized bed gasification method according to any one of claims 1 to 3, wherein the temperature of the first chamber is controlled by adjusting a supply amount of a fluid medium supplied to the first chamber.   The tar generated by the gasification reaction in the second chamber is measured to obtain a tar measurement value, and the tar measurement value coincides with the tar set value as an indicator of the end of the thermal decomposition reaction in the first chamber, The fluidized bed gasification method according to claim 4, wherein the temperature of the first chamber is controlled so that the tar measurement value matches the tar setting value. Char and fluid medium generated during gasification of organic materials are introduced into a fluidized bed combustion furnace and heated while the char is burned to heat the fluidized medium, and the fluidized medium from the fluidized bed combustion furnace is separated by a separator. Then, the separated fluidized medium is introduced into a fluidized bed gasification furnace to form a fluidized bed, and an organic material is supplied to the fluidized bed gasification furnace to extract a product gas generated by gasification of the organic material, A fluidized bed gasification apparatus configured to circulate a part of char and fluidized medium generated during gasification of an organic raw material in a gasification furnace to the fluidized bed combustion furnace,
Said fluidized bed gasification furnace, provided with a material supply device and the first chamber for performing a thermal decomposition reaction of the organic raw material, the pyrolysis residue produced by pyrolysis reaction of organic raw material in the first chamber in the interior of the fluidized bed And a second chamber for introducing a gasification reaction and controlling the temperature of the first chamber by distributing and supplying the fluid medium from the separator to the first chamber and the second chamber. A fluidized bed gasifier comprising temperature control means and pressure control means for controlling the pressure in the first chamber by adjusting the extraction of the pyrolysis gas generated in the first chamber.   The fluidized bed gasifier according to claim 6, further comprising a pyrolysis gas pipe for supplying a pyrolysis gas generated by a pyrolysis reaction of the organic material in the first chamber to a fluidized bed combustion furnace.   The fluidized bed gasifier according to claim 6 or 7, wherein the raw material supply device is provided to supply an organic material to an upper space of the fluidized bed in the first chamber.   The temperature control means includes a distribution device that distributes and supplies the fluid medium from the separator to the first chamber and the second chamber, a thermometer that measures the temperature in the first chamber, and a detected temperature of the thermometer. 9. A fluid medium controller configured to control a supply amount of a fluid medium supplied to the first chamber and the second chamber by the distributor so as to reach a set temperature. Fluidized bed gasifier described in 1.   The pressure control means includes a pressure gauge that detects the pressure in the first chamber, and a gas extraction that adjusts the amount of pyrolysis gas generated in the first chamber so that the detected pressure of the pressure gauge becomes a set pressure. The fluidized bed gasifier according to any one of claims 6 to 9, characterized by comprising a quantity controller. CH reference value obtained in advance for the amount of hydrocarbon components produced when the unit amount of the organic raw material is fluidly heated;
CH measurement value from a CH measuring instrument that measures the amount of hydrocarbon CH-containing component produced by the pyrolysis reaction in the first chamber;
Input a raw material supply amount from a raw material supply amount detector that measures the supply amount of the organic raw material supplied to the first chamber by the raw material supply device,
The CH correction value which corrects the pressure by the said pressure control means so that the said CH measurement value may correspond to the CH prediction value calculated | required from the said CH reference value and the said raw material supply amount is provided. 10 is a fluidized bed gasifier.   A tar measuring instrument that obtains a tar measurement value by measuring the amount of tar generated by the gasification reaction in the second chamber, and inputs the tar measurement value from the tar measuring instrument, and the tar measurement value is the tar set value. The fluidized bed gasifier according to any one of claims 6 to 11, further comprising a tar corrector that corrects the temperature by the temperature control means.

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