JP2010209192A - Method and apparatus for controlling gasification in circulating fluidized-bed gasification plant - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enable a gasification plant to stably correspond to the change of the required amount for gasification gas by a gasified gas-utilizing apparatus, and the change of the required amount for steam by a steam-utilizing apparatus while maintaining the gasification efficiency and the installation-operating efficiency at the gasification in the optimum conditions. <P>SOLUTION: A method for controlling the gasification in a circulating fluidized bed gasification plant includes: previously obtaining the amount of a raw material to be fed to a gasification furnace 1, and the balance amount of the produced gasification gas amount and the produced steam amount when the gasification efficiency is kept optimum and when the retention time of the raw material in the gasification furnace and the amount of the steam to be fed to the gasification furnace are variable; feeding the raw material in the feed amount according to the set requirement 24 for the gasification gas to the gasification furnace 1; operating the retention time of the raw material in the gasification furnace 1 and the amount of the steam for the gasification; feeding air, in an amount sufficient for the combustion of char fed from the gasification furnace 1 to the combustion furnace 2, to a combustion furnace 2; feeding the water, in an amount sufficient for the recovery of waste heat of the combustion gas 4 from the combustion furnace 2, to a waste heat-recovering boiler 16; and feeding the steam, in an amount corresponding to the charged amount of the raw material in the steam 19 formed at the waste heat-recovering boiler 16, to the gasification furnace 1. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  While maintaining gasification efficiency and equipment operation efficiency at the time of gasification in an optimal state, the present invention is adapted to changes in the gasification gas requirement of the gasification gas utilization device and changes in the water vapor requirement of the steam utilization device. The present invention relates to a gasification control method and apparatus for a circulating fluidized bed gasification facility that is capable of responding stably and stably.

  Conventionally, various gasification facilities have been proposed. For example, a circulating fluidized bed gasification facility having a gasification device called a two-column gasification furnace composed of a fluidized bed gasification furnace and a combustion furnace is considered. (See Patent Document 1).

  The circulating fluidized bed gasification facility has a combustion furnace and a gasification furnace, the fluid medium heated in the combustion furnace is introduced into the gasification furnace, and the raw material is supplied by the steam supplied from the lower part and the heat of the fluid medium. Gasified to produce gasified gas, the fluidized medium of the gasifier and unreacted char are introduced into the combustion furnace, and the char is burned with combustion air to heat the fluidized medium and lead out from the combustion furnace The fluid medium separated from the combustion gas is circulated to the gasifier.

  Further, steam is supplied as a gasifying agent to the gasification furnace, and as the steam, steam produced by an auxiliary boiler or the like provided separately is used, or the gasification furnace in the circulating fluidized bed gasification facility is used. It has been considered to use steam generated by an exhaust heat recovery boiler that exchanges heat between combustion gas and water from a combustion furnace.

  Examples of the circulating fluidized bed gasification equipment include those that are difficult to effectively use as fuel, such as biomass, sludge, or petroleum production residue, and sub-bituminous coal, lignite, peat, etc. Can also be used effectively as a raw material, and can produce a useful gasification gas close to natural gas, and thus has attracted attention as a very promising technology.

  Furthermore, in the circulating fluidized bed gasification equipment, the fluidized medium is heated by burning unreacted char that has not been gasified in the gasifier in the combustion furnace, and the heated fluidized medium is circulated to the gasifier. Since heat necessary for gasification (endothermic reaction) of the raw material is supplied, there is an advantage that the gasification cycle can be thermally independent only by supplying the raw material to the gasification furnace.

  In a conventional circulating fluidized bed gasification facility, the gasified gas generated in the gasifier is supplied to a gas turbine generator for power generation, and exhaust heat is exchanged with the combustion gas from the combustion furnace. The steam generated by the recovery boiler (steam other than that supplied to the gasifier) is supplied to the steam turbine generator for power generation, and the power generation equipment for obtaining a certain amount of power generation is mainly used in this way. It was thought.

On the other hand, in recent years, the circulating fluidized bed gasification facility is applied to, for example, a chemical fertilizer factory, and the generated gasification gas is used as a gasification gas utilization apparatus for producing a chemical fertilizer such as ammonia (urea). It is considered that the water vapor that is supplied and generated is supplied to a water vapor utilization device that is used as air conditioning in a factory or other heat source or cold source.
Japanese Patent Laid-Open No. 2005-041959

  In chemical fertilizer factories and the like, the required amount of gasification gas (maximum value that can be stably generated) to be generated by the circulating fluidized bed gasification equipment is determined in advance, and therefore the gasification efficiency is at this gasification gas requirement amount. The operation of the circulating fluidized bed gasification facility is controlled so as to be optimal, but the gasification gas requirement may decrease due to production reduction in the gasification gas utilization device, and the steam utilization device The required amount of water vapor may vary greatly depending on the season and time.

  However, since the circulation fluidized bed gasification equipment considered conventionally is not assumed to be applied to the above-mentioned chemical fertilizer factories, etc., the gasification gas requirement amount or the water vapor requirement amount individually varies. This has not been taken into consideration, and therefore has the problem that it is difficult to meet each requirement together. Conventionally, steam that is deficient in other equipment such as a boiler is generated, but there is a problem that the installation space of the equipment and the burden of operation and maintenance are increased, and the operation efficiency of the circulating fluidized bed gasification facility is reduced.

  The present invention has been made in view of the above-described conventional problems, while maintaining the gasification efficiency and equipment operation efficiency at the time of gasification in an optimal state, changes in the gasification gas requirement amount of the gasification gas utilization device, Another object of the present invention is to provide a gasification control method and apparatus for a circulating fluidized bed gasification facility capable of stably responding to changes in the required amount of steam in the steam utilization device.

The present invention provides a gasification furnace that introduces a heated fluid medium and gasifies a raw material by heat of the fluid medium in the presence of water vapor to generate a gasification gas, and supplies the gasification gas generated in the gasification furnace Gasification gas utilization apparatus, combustion furnace for heating the fluidized medium by introducing a fluidized medium and an unreacted char of the gasification furnace, and burning the auxiliary fuel supplied with the char as needed with combustion air And a separator that separates the fluidized medium from the combustion gas derived from the combustion furnace and introduces the fluidized medium into the gasifier, and at least heats the combustion gas and water separated from the fluidized medium to generate water vapor. A gasification control method for a circulating fluidized bed gasification facility comprising an exhaust heat recovery boiler and a steam utilization device that supplies the remaining steam that is generated by the exhaust heat recovery boiler and partially supplied to the gasification furnace. And
The balance amount of the raw material supply amount, gasification gas generation amount and water vapor generation amount to the gasification furnace when the gasification efficiency is maintained optimally is determined in advance,
The amount of air supply sufficient to supply the raw material supply amount according to the required amount of gasification gas set in the circulating fluidized bed gasification facility to the gasification furnace and to burn the char supplied from the gasification furnace to the combustion furnace Is supplied to the combustion furnace, and a sufficient amount of water supply to recover the exhaust heat of the combustion gas from the combustion furnace is supplied to the exhaust heat recovery boiler, corresponding to the raw material input amount of water vapor generated in the exhaust heat recovery boiler The present invention relates to a gasification control method for a circulating fluidized bed gasification facility, characterized in that a steam supply amount is supplied to a gasification furnace to stably operate the circulating fluidized bed gasification facility.

  In the gasification control method for the circulating fluidized bed gasification facility, when a command to reduce the required amount of gasification gas is issued from the gasification gas utilization device in the state of stable operation, raw material supply to the gasification furnace is performed. At the same time as reducing the amount, it is preferable to shorten the residence time of the raw material in the gasification furnace and reduce the gasification gas generation amount in accordance with the reduction command.

  In the gasification control method for the circulating fluidized bed gasification facility, it is preferable to reduce the amount of water vapor supplied into the gasification furnace when a command for reducing the gasification gas requirement is issued.

  Further, in the gasification control method of the circulating fluidized bed gasification facility, when an increase command is issued with respect to the amount of steam generated balanced from the steam utilization device, the amount of water supplied to the exhaust heat recovery boiler is increased and combustion is performed. It is preferable to increase the amount of combustion air supplied to the furnace.

  Further, in the gasification control method for the circulating fluidized bed gasification facility, when an increase command is issued for the steam generation amount balanced from the steam utilization device, the amount of water supplied to the exhaust heat recovery boiler is increased, and the gas It is preferable to increase the amount of raw material supplied to the gasification furnace, shorten the residence time of the raw material in the gasification furnace, and further increase the amount of combustion air supplied to the combustion furnace.

  Further, in the gasification control method of the circulating fluidized bed gasification facility, when an increase command is issued with respect to the amount of steam generated balanced from the steam utilization device, the amount of water supplied to the exhaust heat recovery boiler is increased and combustion is performed. It is preferable to supply auxiliary fuel to the furnace and to further increase the amount of combustion air supplied to the combustion furnace.

The present invention provides a gasification furnace that introduces a heated fluid medium and gasifies a raw material by heat of the fluid medium in the presence of water vapor to generate a gasification gas, and supplies the gasification gas generated in the gasification furnace Gasification gas utilization apparatus, combustion furnace for heating the fluidized medium by introducing a fluidized medium and an unreacted char of the gasification furnace, and burning the auxiliary fuel supplied with the char as needed with combustion air And a separator that separates the fluidized medium from the combustion gas derived from the combustion furnace and introduces the fluidized medium into the gasifier, and at least heats the combustion gas and water separated from the fluidized medium to generate water vapor. A gasification control device for a circulating fluidized bed gasification facility, comprising: an exhaust heat recovery boiler; and a steam utilization device that supplies the remaining steam generated in the exhaust heat recovery boiler and partially supplied to the gasification furnace. And
Obtain and input in advance the balance of raw material supply amount and gasification gas generation amount and steam generation amount to the gasification furnace when the gasification efficiency is kept optimal,
The amount of air supply sufficient to supply the raw material supply amount according to the required amount of gasification gas set in the circulating fluidized bed gasification facility to the gasification furnace and to burn the char supplied from the gasification furnace to the combustion furnace Is supplied to the combustion furnace, and a sufficient amount of water supply to recover the exhaust heat of the combustion gas from the combustion furnace is supplied to the exhaust heat recovery boiler, corresponding to the raw material input amount of water vapor generated in the exhaust heat recovery boiler The present invention relates to a gasification control device for a circulating fluidized bed gasification facility, comprising a target follow-up device that controls the supply of water vapor to a gasification furnace to perform stable operation.

  In the gasification control device of the circulating fluidized bed gasification facility, it is preferable that the exhaust heat recovery boiler simultaneously recovers the heat of the gasification gas taken out from the gasification furnace.

  Further, in the gasification control device for the circulating fluidized bed gasification facility, when the gasification gas utilization device issues a command for reducing the gasification gas demand, control is performed to reduce the amount of raw material supplied to the gasification furnace. It is preferable to have the target follower and a residence time adjusting means for shortening the residence time of the raw material in the gasification furnace.

  Further, in the gasification control device for the circulating fluidized bed gasification facility, the residence time adjusting means is a steam supply device for ejecting water vapor in a direction to suppress the progress of the raw material in the gasification furnace or to assist the progress. That is preferred.

  Further, in the gasification control device of the circulating fluidized bed gasification facility, the dwell time adjusting means is an obstacle to be inserted into the fluidizing medium of the gasification furnace so as to suppress the progress of the raw material in the gasification furnace. It is preferable that it is a member.

  The gasification gas set in the circulating fluidized bed gasification facility is obtained in advance by obtaining the balance between the raw material supply amount, the gasification gas generation amount and the water vapor generation amount to the gasification furnace when the gasification efficiency is optimally maintained. Supply the raw material supply amount according to the required amount to the gasification furnace, supply the air supply amount sufficient to burn the char supplied from the gasification furnace to the combustion furnace, and the combustion gas from the combustion furnace A sufficient water supply amount to recover the exhaust heat of the steam is supplied to the exhaust heat recovery boiler, and a steam supply amount corresponding to the raw material input amount of the steam generated in the exhaust heat recovery boiler is supplied to the gasifier. As a result, the circulating fluidized bed gasification facility can be stably operated to produce an excellent effect that gasified gas is stably generated.

  When a gasification gas requirement reduction command was issued from the gasification gas utilization device, the raw material supply amount to the gasification furnace was reduced, and at the same time, the residence time of the raw material in the gasification furnace was shortened. The effect of reducing the gasification efficiency and reducing the amount of gasified gas produced in accordance with the reduction command, while maintaining the amount of char introduced into the combustion furnace and maintaining the amount of water vapor produced There is.

  When the gasification gas requirement reduction command is issued, the gasification efficiency is reduced by reducing the amount of water vapor supplied into the gasification furnace. This has the effect of complying with the reduction command.

  On the other hand, when an instruction to increase the amount of steam generated is issued from the steam utilization device from the state where gasification is stably performed, the amount of water supplied to the exhaust heat recovery boiler is increased and the air supply to the combustion furnace is increased. By increasing the amount, there is an effect that the amount of steam generated can be increased by increasing the amount of exhaust heat recovered by the exhaust heat recovery boiler.

  In addition, when an instruction to increase the amount of steam generated is issued from the steam utilization device, the amount of water supplied to the exhaust heat recovery boiler is increased, the amount of raw material supplied to the gasifier is increased, and the raw material stays in the gasifier By shortening the time and further increasing the amount of air supplied to the combustion furnace, there is an effect that the amount of water vapor generated can be significantly increased within a range in which the gasification efficiency is not lowered.

  In addition, when a steam generation amount increase command is issued from the steam utilization device, the amount of water supplied to the exhaust heat recovery boiler is increased, auxiliary fuel is supplied to the combustion furnace, and the air supply amount to the combustion furnace As a result, the amount of water vapor generated by the exhaust heat recovery boiler can be significantly increased regardless of the gasification operation.

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

  FIG. 1 is a block diagram showing an outline of a circulating fluidized bed gasification facility of the present invention applied to a chemical fertilizer factory. A circulating fluidized bed gasification facility having a gasifier called a two-column gasifier is A fluidizing medium 3 having a gasification furnace 1 and a combustion furnace 2 is introduced into a cyclone type separator 5 together with the combustion gas 4 and separated from the combustion gas 4 to be gasified. Supplied to the furnace 1. The raw material 7 is supplied from the raw material supply device 6 to the gasification furnace 1 and the water vapor 9 is supplied from the steam valve 8. The raw material 7 supplied to the gasification furnace 1 is in the presence of the water vapor 9. Gasified (endothermic reaction) is generated by the heat of the fluidized medium 3 to generate a gasified gas 10, and the generated gasified gas 10 is gasified to produce a chemical fertilizer such as ammonia (urea) provided in a fertilizer factory. The gas is supplied to the gas utilization device 11.

  The fluidized medium 3 in the gasification furnace 1 and unreacted char are introduced into the combustion furnace 2, and the char is burned by the combustion air 13 supplied from below by the blower fan 12 to heat the fluidized medium 3. It is supposed to be.

  Reference numeral 14 denotes an auxiliary fuel supply device that supplies the combustion furnace 2 with an auxiliary fuel 15 such as a gas, a liquid, or a solid to increase the calorific value of the combustion furnace.

  Reference numeral 16 denotes an exhaust heat recovery boiler in which water 18 is supplied by a feed water pump 17. The exhaust heat recovery boiler 16 exchanges heat between the combustion gas 4 from the separator 5 and the water 18, and The gasification gas 10 generated in the gasification furnace 1 is also heat-exchanged to generate water vapor 19, and a part of the generated water vapor 19 is used as the gasification water vapor 9 for the steam valve 8. The remaining water vapor 19 other than being supplied to the gasification furnace 1 and led to the gasification furnace 1 is supplied to a water vapor utilization device 20 such as an air conditioner provided in the fertilizer factory.

  Reference numeral 21 denotes a target follower. The target follower 21 includes a detection signal from a gasification gas generation amount detector 22 that detects the amount of gasification gas generated in the gasification furnace 1, and exhaust heat recovery. A detection signal from a water vapor generation amount detector 23 that detects the amount of water vapor generated in the boiler 16 is input.

  In a state where efficient gasification is performed by the circulating fluidized bed gasification facility of FIG. 1, as shown in FIG. 2A, the gasification gas generation is performed with respect to the raw material supply amount supplied to the gasification furnace 1. The amount A and the water vapor generation amount B are uniquely determined balanced amounts. Therefore, the balance amount of the gasification gas generation amount A and the water vapor generation amount B with respect to the raw material supply amount described above is obtained in advance, and the target It inputs into the tracking apparatus 21 as a table. FIG. 2 shows a case of an operation example in which the required amount of gasification gas = the maximum amount of gasification gas generation. In the figure, the gasification gas generation amount A and the water vapor generation amount B are shown by straight lines. It is considered a curve.

  Accordingly, when the gasification gas requirement amount 24 (maximum value that can be stably generated by the circulating fluidized bed gasification facility) is set in the target follower 21, the target follower 21 outputs a control command 26, and the raw material supply device 6 The amount of raw material supplied, the amount of water vapor supplied by the steam valve 8, the amount of water supplied by the water supply pump 17, and the amount of combustion air supplied by the blower fan 12 are controlled. As a result, the circulating fluidized bed gasification facility is operated in a stable state. A gasification gas generation amount A corresponding to the required amount 24 is obtained, and a water vapor generation amount B balanced according to the gasification gas generation amount A is obtained.

  Further, the target follower 21 is supplied with a required water vapor amount 25 that is a required amount of the water vapor utilization device 20. This water vapor requirement amount 25 is set within the range of the water vapor production amount B produced in balance with the gasification gas production amount A.

  As shown in FIGS. 3 and 4, the gasification furnace 1 is provided with residence time adjusting means 27 for adjusting the residence time of the raw material in the gasification furnace 1. A fluidized bed 28 is formed in the gasification furnace 1 by steam 9 blown from below, and the fluidized medium 3 and the raw material 7 supplied from one end side of the gasification furnace 1 move while flowing toward the other end side. The char and the fluid medium 3 are taken out from the take-out part 29 on the other end side and supplied to the combustion furnace 2 (see FIG. 1). An injection nozzle 31 in which water vapor 30 is blown into the side portion of the gasification furnace 1 so as to intersect at right angles from the side with respect to the moving direction of the fluid medium 3 and the raw material 7 flowing from the one end to the other end. The residence time adjusting means 27 having the above is provided. Furthermore, the residence time adjusting means 27 includes a steam valve 34 that adjusts the amount of steam 30 that is injected from the side of the gasification furnace 1 by the injection nozzle 31 according to an adjustment command 33 from the residence time adjuster 32. In addition, the progress of the raw material in the gasification furnace 1 is suppressed by the water vapor 30 blown from the side, and the residence time of the raw material is adjusted. At this time, if the injection amount of the water vapor 30 is increased, the progress of the raw material is suppressed and the residence time is lengthened. Conversely, if the injection amount of the water vapor 30 is decreased, the raw material is easily advanced and the residence time is shortened. Also, when water vapor is injected from one end side of the gasification furnace 1 toward the other end side so as to help the progress of the raw material, the residence time of the raw material can be easily adjusted. The combination of the structure for injecting water vapor to help the progress of the raw material and the structure for injecting water vapor 30 in the direction to suppress the progress of the raw material as shown in FIGS. Wide adjustment range can be set.

  5 and 6 show another example of the residence time adjusting means 27. Similarly to FIGS. 3 and 4, the fluidized medium 3 and the raw material 7 are supplied from one end side of the gasification furnace 1 to the other end side. In the configuration that moves while flowing toward the side, the residence time adjustment has a plate-like baffle member 35 extending in the width direction so as to hinder the movement of the raw material between the one end and the other end. Means 27 are provided. Further, the residence time adjusting means 27 is provided with a drive device 36 that adjusts the depth at which the baffle member 35 is inserted into the fluidized bed 28 in accordance with an adjustment command 33 from the residence time adjuster 32. When the baffle member 35 is inserted into the fluidized bed 28, the raw material cannot flow to the extraction portion 29 side unless it penetrates the lower end of the baffle member 35, so the insertion depth of the baffle member 35 into the fluidized bed 28 is increased. Then, the residence time of a raw material can be adjusted long.

  The operation of the above embodiment will be described below.

  The target follower 21 shown in FIG. 1 receives a gasification gas requirement amount 24 (the maximum value that can be stably generated by the circulating fluidized bed gasification facility). The target follower 21 is shown in FIG. As described above, since the balance amount of the gasification gas generation amount A and the water vapor generation amount B with respect to the raw material supply amount is input in advance, the target follower 21 outputs a control command 26 based on the gasification gas request amount 24. The raw material supply device 6 is controlled to supply the raw material 7 necessary for obtaining the required gasification gas amount 24 to the gasification furnace 1, and the char supplied from the gasification furnace 1 to the combustion furnace 2 is burned. The blower fan 12 is controlled so that sufficient combustion air 13 is supplied to the combustion furnace 2, and water 18 sufficient to recover the exhaust heat of the combustion gas 4 from the combustion furnace 2 is supplied to the exhaust heat recovery boiler 16. The feed water pump 17 is controlled so that the raw material 7 is supplied. The steam valve 8 is controlled so that the steam 9 corresponding to the amount is supplied to the gasification furnace 1, whereby the gasification gas 10 is stably generated and generated so that the gasification gas requirement amount 24 is obtained. The gasified gas 10 is supplied to the gasified gas utilization device 11. Further, the exhaust heat recovery boiler 16 generates steam 19 having a steam generation amount B (see FIG. 2A) balanced with the gasification gas requirement amount 24, and a part of the steam 19 is used as gasification steam 9. 1 and the remaining water vapor 19 is stably supplied to the water vapor utilization apparatus 20.

  Here, the maximum required gasified gas amount 24 does not increase from this value, but the gasified gas required amount 24 may decrease due to a reduction in production in the gasified gas utilization device 11 or the like.

  When the gasification gas utilization device 11 issues a command 24 ′ for reducing the gasification gas requirement amount 24 ′, the target follower device 21 sets the balance amount in FIG. Based on this, steps S1 and S2 shown in the control flowchart of FIG. 7 are controlled. Here, an example in which the gasification gas generation amount A is decreased without changing the water vapor generation amount B is shown. That is, in step S1, it is determined whether or not there is a reduction command 24 ′ for the gasification gas request amount 24. If there is a reduction command 24 ′, the supply amount of the raw material 7 to the gasification furnace 1 is reduced by the raw material supply device 6. And the operation of shortening the residence time of the raw material in the gasification furnace 1 is performed. In order to shorten the residence time of the raw material, in the case of the form of FIG. 3 and FIG. 4, by reducing the amount of steam 30 blown from the side of the gasification furnace 1 by the injection nozzle 31, In the case of the form of FIGS. 5 and 6, by reducing the insertion depth of the baffle member 35 inserted into the fluidized bed 28 of the gasification furnace 1, The residence time of the raw material in the gasification furnace 1 is shortened. In the above, when the supply amount of the raw material 7 to the gasification furnace 1 is decreased by the raw material supply device 6, the supply amount of the steam 9 to the gasification furnace 1 may be decreased correspondingly. Both the shortening of the residence time and the reduction of the water supply amount may be performed, or one of them may be performed.

  As described above, when there is a reduction command 24 ′, only by reducing the supply amount of the raw material 7 as shown in FIG. 2 (b), the amount of char introduced into the combustion furnace 2 is also reduced. The amount decreases, the water vapor requirement cannot be satisfied, and thermal independence becomes difficult. Since the raw material supply amount is greatly reduced, the operation efficiency of the entire circulating fluidized bed gasification facility is lowered. Moreover, in order to make up for the deficient water vapor, a separate raw material for operating another device such as a boiler is required. On the other hand, as described above, when the operation for reducing the supply amount of the raw material 7, the operation for shortening the residence time of the raw material in the gasification furnace 1, and the operation for reducing the water vapor supply to the gasification furnace 1 are performed. As shown in FIG. 2 (c), control is performed so that the gasification gas amount decreases along the decrease command 24 ′ without changing the water vapor generation amount.

  Further, the water vapor requirement amount 25 by the water vapor utilization device 20 is adjusted within the range of the water vapor production amount B generated in balance with the gasification gas production amount A in FIG. Depending on the time or the like, an increase command 25 ′ for increasing the water vapor requirement 25 may be issued.

  When an increase command 25 ′ for the required steam amount 25 is issued from the steam utilization device 20, the target follower device 21 performs the first control method in steps S 3 and S 4 shown in the control flowchart of FIG. ing. That is, in step S3, it is determined whether or not there is an increase command 25 ′ for the water vapor requirement 25, and when it is determined that there is an increase command 25 ′, the first control method shown in FIG. The operation of adjusting the feed water pump 17 to increase the amount of water supply to the exhaust heat recovery boiler 16 and the operation of adjusting the blower fan 12 to increase the supply amount of the combustion air 13 to the combustion furnace 2 are performed. ing.

  As shown in FIG. 7, when the increase command 25 ′ for the steam requirement 25 is issued, if the supply amount of the combustion air 13 to the combustion furnace 2 is increased, the flow rate of the combustion gas 4 is increased, so that exhaust heat recovery is performed. The amount of exhaust heat recovered by the boiler 16 increases, and the amount of water vapor 19 generated increases. When the increase width of the increase command 25 ′ is relatively small or short, the generation amount can be increased by a simple method based on the first control method described above.

  FIG. 8 shows a second control method when an increase command 25 ′ for the water vapor requirement 25 is issued. When it is determined in step S3 that the increase command 25 ′ has been issued, as shown in step S5. 3, an operation for adjusting the feed water pump 17 to increase the amount of water supplied to the exhaust heat recovery boiler 16, an operation for adjusting the raw material supply device to increase the supply amount of the raw material 7 to the gasifier 1, and FIG. The operation of shortening the residence time of the raw material in the gasification furnace 1 by the apparatus of FIG. 6 and the operation of adjusting the blower fan 12 to further increase the supply amount of the combustion air 13 to the combustion furnace 2 are performed. ing.

  As shown in FIG. 8, when an increase command 25 ′ for the steam requirement 25 is issued, an increase in the amount of water supplied to the exhaust heat recovery boiler 16, an increase in the amount of raw material 7 supplied to the gasifier 1, and gas By reducing the residence time of the raw material in the gasification furnace 1 and increasing the supply amount of the combustion air 13 to the combustion furnace 2, an increase in the water vapor requirement amount 25 within a range in which the gasification efficiency in the gasification furnace 1 is not lowered. Based on the command 25 ′, the water vapor generation amount can be greatly increased and supplied to the water vapor utilization apparatus 20.

  FIG. 9 shows a third control method when an increase command 25 'for the water vapor requirement 25 is issued. When it is determined in step S3 that the increase command 25' has been issued, as shown in step S6. In addition, an operation of adjusting the feed water pump 17 so as to increase the amount of water supplied to the exhaust heat recovery boiler 16, an operation of supplying the auxiliary fuel 15 to the combustion furnace 2 by the auxiliary fuel supply device 14, and a combustion furnace 2 And the operation of adjusting the blower fan 12 so as to increase the amount of supply of the combustion air 13 to the air.

  As shown in FIG. 9, when an increase command 25 ′ for the water vapor requirement 25 is issued, the increase in the amount of water supplied to the exhaust heat recovery boiler 16, the supply of the auxiliary fuel 15 to the combustion furnace 2, and the combustion furnace 2 By increasing the supply amount of the combustion air 13 with respect to the steam, the steam generation amount by the exhaust heat recovery boiler 16 is greatly increased on the basis of the increase command 25 ′ of the steam request amount 25 regardless of the gasification operation, and the steam utilization device 20 can be supplied.

  Further, when the raw material 7 supplied to the gasification furnace 1 is changed, the balance amount of the gasification gas generation amount A and the steam generation amount B with respect to the raw material supply amount shown in FIG. By correcting the table input to the tracking device 21, even when the raw material is changed, it is possible to stably cope with the change in the gasification gas demand and the steam demand of the steam utilization device. Can do.

  In addition, in the said form, although illustrated about the case of the circulating fluidized bed gasification equipment applied to the chemical fertilizer factory, the gasification gas and water vapor | steam produced | generated by a circulating fluidized bed gasification equipment are utilized besides a chemical fertilizer factory. Needless to say, the present invention can be applied to various facilities that can be used, and various modifications can be made without departing from the scope of the present invention.

It is a block diagram which shows the outline of the circulating fluidized-bed gasification equipment of this invention applied to the chemical fertilizer factory. It is a graph which shows the state which the gasification gas production amount and the water vapor production amount balanced with respect to the raw material supply amount. It is a perspective view which shows an example of a residence time adjustment means. FIG. 4 is a plan view of FIG. 3. It is a perspective view which shows the other example of a residence time adjustment means. FIG. 6 is a plan view of FIG. 5. It is a control flowchart which shows the control method when the reduction | decrease command of gasification gas request | requirement amount generate | occur | produces, and the 1st control method when the increase command of water vapor | steam request | requirement amount is issued. In FIG. 7, it is a control flowchart which shows the 2nd control method when the increase instruction | indication of water vapor | steam request | requirement amount is issued. In FIG. 7, it is a control flowchart which shows the 3rd control method when the increase instruction | command of water vapor | steam request | requirement amount is issued.

DESCRIPTION OF SYMBOLS 1 Gasification furnace 2 Combustion furnace 3 Fluid medium 4 Combustion gas 5 Separator 7 Raw material 9 Water vapor 10 Gasification gas 11 Gasification gas utilization apparatus 13 Combustion air 15 Auxiliary fuel 16 Waste heat recovery boiler 18 Water 19 Water vapor 20 Steam utilization apparatus 21 Target follower 24 Gasification gas requirement 24 'Decrease command 25 Steam requirement 25' Increase command 27 Residence time adjustment means 30 Steam 35 Block member A Gasification gas production amount B Steam production amount H Residence time H1 Residence time S Raw material stop time

Claims (11)

A gasification furnace that introduces a heated fluid medium and gasifies the raw material by the heat of the fluid medium in the presence of water vapor to generate a gasification gas, and a gasification gas that supplies the gasification gas generated in the gasification furnace A combustion furnace that heats the fluidized medium by introducing a fluidized medium and an unreacted char of the gasification furnace and burning auxiliary fuel supplied together with the char as necessary with combustion air, and the combustion A separator that separates a fluidized medium from a combustion gas derived from a furnace and introduces the fluidized medium into the gasification furnace, and an exhaust heat recovery boiler that generates water vapor by exchanging heat between at least the combustion gas from which the fluidized medium is separated and water And a gasification control method of a circulating fluidized bed gasification facility having a steam utilization device that supplies the remaining steam that is generated in the exhaust heat recovery boiler and a part of which is supplied to the gasification furnace,
The balance amount of the raw material supply amount, gasification gas generation amount and water vapor generation amount to the gasification furnace when the gasification efficiency is maintained optimally is determined in advance,
The amount of air supply sufficient to supply the raw material supply amount according to the required amount of gasification gas set in the circulating fluidized bed gasification facility to the gasification furnace and to burn the char supplied from the gasification furnace to the combustion furnace Is supplied to the combustion furnace, and a sufficient amount of water supply to recover the exhaust heat of the combustion gas from the combustion furnace is supplied to the exhaust heat recovery boiler, corresponding to the raw material input amount of water vapor generated in the exhaust heat recovery boiler A gasification control method for a circulating fluidized bed gasification facility, characterized in that a steam supply amount is supplied to a gasification furnace to stably operate the circulating fluidized bed gasification facility.   In the state of stable operation, when a gasification gas requirement reduction command is issued from the gasification gas utilization device, the raw material supply amount to the gasification furnace is reduced and at the same time, the retention of the raw material in the gasification furnace The gasification control method for a circulating fluidized bed gasification facility according to claim 1, wherein the gasification gas generation amount is reduced in accordance with a reduction command by shortening the time.   The gasification control method for a circulating fluidized bed gasification facility according to claim 1 or 2, wherein the amount of water vapor supplied into the gasification furnace is reduced when a command for reducing the gasification gas requirement amount is issued.   4. The method according to claim 1, wherein when an increase command is issued with respect to the amount of steam generated balanced from the steam utilization device, the amount of water supplied to the exhaust heat recovery boiler is increased and the amount of combustion air supplied to the combustion furnace is increased. A gasification control method for a circulating fluidized bed gasification facility according to claim 1.   When an increase command is issued for the amount of steam generated from the steam utilization device, the amount of water supplied to the exhaust heat recovery boiler is increased, the amount of raw material supplied to the gasifier is increased, and the raw material in the gasifier The gasification control method of the circulating fluidized-bed gasification facility according to any one of claims 1 to 3, wherein the residence time of the gas is reduced and the amount of combustion air supplied to the combustion furnace is increased.   When a command to increase the amount of steam generated from the steam utilization device is issued, the amount of water supplied to the exhaust heat recovery boiler is increased, auxiliary fuel is supplied to the combustion furnace, and combustion to the combustion furnace is performed. The gasification control method for a circulating fluidized bed gasification facility according to any one of claims 1 to 3, wherein the air supply amount is increased. A gasification furnace that introduces a heated fluid medium and gasifies the raw material by the heat of the fluid medium in the presence of water vapor to generate a gasification gas, and a gasification gas that supplies the gasification gas generated in the gasification furnace A combustion furnace that heats the fluidized medium by introducing a fluidized medium and an unreacted char of the gasification furnace and burning auxiliary fuel supplied together with the char as necessary with combustion air, and the combustion A separator that separates a fluidized medium from a combustion gas derived from a furnace and introduces the fluidized medium into the gasification furnace, and an exhaust heat recovery boiler that generates water vapor by exchanging heat between at least the combustion gas from which the fluidized medium is separated and water And a gasification control device of a circulating fluidized bed gasification facility having a steam utilization device that supplies the remaining steam that is generated in the exhaust heat recovery boiler and partly supplied to the gasification furnace,
Obtain and input in advance the balance of raw material supply amount and gasification gas generation amount and steam generation amount to the gasification furnace when the gasification efficiency is kept optimal,
The amount of air supply sufficient to supply the raw material supply amount according to the required amount of gasification gas set in the circulating fluidized bed gasification facility to the gasification furnace and to burn the char supplied from the gasification furnace to the combustion furnace Is supplied to the combustion furnace, and a sufficient amount of water supply to recover the exhaust heat of the combustion gas from the combustion furnace is supplied to the exhaust heat recovery boiler, corresponding to the raw material input amount of water vapor generated in the exhaust heat recovery boiler A gasification control device for a circulating fluidized bed gasification facility, comprising a target tracking device that controls to supply a steam supply amount to a gasification furnace so as to perform a stable operation.   The gasification control device for a circulating fluidized bed gasification facility according to claim 7, wherein the exhaust heat recovery boiler also recovers the heat of the gasification gas taken out from the gasification furnace at the same time.   When the gasification gas utilization device issues a gasification gas requirement reduction command, the target tracking device that performs control to reduce the amount of raw material supply to the gasification furnace, and the residence time of the raw material in the gasification furnace The gasification control device for a circulating fluidized bed gasification facility according to claim 7 or 8, further comprising a residence time adjusting means for shortening.   The gasification control of the circulating fluidized bed gasification facility according to claim 9, wherein the residence time adjusting means is a water vapor supply device that ejects water vapor in a direction that suppresses the progress of the raw material in the gasification furnace or a direction that helps the progress. apparatus.   The circulating fluidized bed gasification facility according to claim 9, wherein the residence time adjusting means is a baffle member inserted into the fluidizing medium of the gasification furnace so as to suppress the progress of the raw material in the gasification furnace. Gasification control device.

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