JP5911916B2 - Syngas supply system - Google Patents

Description

  The present invention relates to a synthesis gas supply system that supplies synthesis gas produced from coal as a raw material.

  In recent years, the use of coal, which is cheap and exists in a wide range of areas, has been reconsidered with rising prices of oil and natural gas.

  Here, in the conventional method of using coal as a solid power plant, the power generation efficiency is reduced by about 20% compared to a combined cycle using natural gas as fuel.

  In addition, the conventional method of using coal in a solid state is limited to the use of a power plant or an iron making plant, and is difficult to use as a raw material for a petrochemical plant such as oil or natural gas.

  Therefore, coal is gasified to produce syngas for use in power plants with a combined cycle with high power generation efficiency that can use coal more efficiently, or as a raw material for petrochemical plants as a new use of coal. A gasifier has been developed.

  The continuous operation time of the current gasifier is about 2 to 3,000 hours at the longest. Therefore, when the continuous operation for 2 to 4 years is used for the raw material of a normal petrochemical plant Since the continuous operation time is short, it is essential to install a plurality of gasifiers to compensate for the short continuous operation time.

  Furthermore, since the properties of the coal to be charged into the gasifier are not always constant, the output of the gasifier may become unstable due to changes in the operating state due to changes in the properties of the coal.

  When a gasifier is used as a fuel for a power plant, the generation output fluctuates greatly even during the day, so the synthesis gas supply from the gasifier cannot follow, and temporarily the synthesis gas from the gasifier There is a possibility that a stable supply of

  Therefore, a method and a plant as in Patent Document 1 have been proposed for keeping the gasifier stable even when there is a load fluctuation.

JP-A-11-22485

  Here, the current gasifier does not reach the level of continuous operation time of gas users such as power plants and petrochemical plants in continuous operation time. The current gasifier stops operation every 2 to 3,000 hours and requires maintenance, so gas is required to stably supply raw materials to petrochemical plants such as 2 to 4 years. Installation of multiple reactors is a prerequisite.

  In addition, the continuous operation time of the gasifier may be shortened depending on the properties of the input coal and fluctuations in the operation load of the gasifier, and the shortening of the continuous operation time of the gasifier remains as it is. Leading to an increase in initial investment costs.

  Here, in the coal gasification power generation method and power plant described in Patent Document 1, large load fluctuations of the gasification furnace are allowed, but this causes gasification furnace to shorten the continuous operation time, resulting in gasification. There is a problem that the initial investment cost of the furnace may increase.

  In view of this problem, the present invention makes it possible to stably supply synthesis gas to a gas user while suppressing the load fluctuation of the gasification furnace as much as possible in order to keep the continuous operation time of the gasification furnace as long as possible. An object is to provide a synthesis gas supply system.

  (1) A synthesis gas supply system according to the present invention is a synthesis gas supply system including a plurality of gasification furnaces for supplying synthesis gas to a plurality of gas users, and a header pipe to which the plurality of gasification furnaces are connected. A gas distribution pipe connecting the header pipe and the gas user, a gas distribution valve installed on the gas distribution pipe, and on the gas distribution pipe between the header pipe and the gas distribution valve A flow rate detection means installed in the control unit, and a control device connected to the flow rate detection means and the gas distribution valve so as to control an opening degree of the gas distribution valve in accordance with a value detected by the flow rate detection means; The control device is configured to control the gas distribution pipe so that the total supply amount of the synthesis gas detected by the flow rate detection means is always lower than a preset maximum supply amount of the synthesis gas. And controlling the degree.

  (2) Further, the synthesis gas supply system according to the present invention provides a minimum supply amount for each gas user in which a supply amount of the synthesis gas supplied to the gas user in the synthesis gas supply system according to (1) is preset. When it is about to fall, the control device performs control to reduce the opening of the gas distribution valve on the gas distribution pipe connected to the other gas user.

  (3) Further, the synthesis gas supply system according to the present invention is the synthesis gas supply system according to (1) or (2), wherein the control device is capable of controlling a synthesis gas production amount in the gasification furnace. The control device is connected to the gasification furnace, and controls to increase the maximum supply amount at the same time as increasing the production amount of the synthesis gas from the gasification furnace in a preset time zone.

  (4) Further, the synthesis gas supply system according to the present invention is the synthesis gas supply system according to any one of (1) to (3), wherein the synthesis gas generated in the gasifier uses coal as a raw material. It is characterized by.

  According to the synthesis gas supply gas system described in (1), the total supply amount of the synthesis gas to the gas user does not exceed the preset maximum supply amount, and the load fluctuation of the gasifier is within a certain range. It is possible to supply synthesis gas to gas users as much as possible.

  According to the synthesis gas supply system described in (2), since the supply amount of the synthesis gas supplied to the gas user does not fall below the minimum supply amount, it is possible to avoid an emergency stop of the equipment on the gas user side. It becomes.

  According to the synthesis gas supply system described in (3), the synthesis gas can be supplied to the gas user more flexibly in accordance with the demand of the gas user.

  According to the synthesis gas supply system described in (4), it is possible to stably supply inexpensive synthesis gas to gas users by using cheap and stably available coal as a raw material for synthesis gas. .

It is a schematic diagram of the synthesis gas supply system which concerns on 1st embodiment. It is a schematic diagram of the time-dependent change of the supply amount of the synthesis gas supply in 1st embodiment. It is a schematic diagram of the synthesis gas supply system which concerns on 2nd embodiment. It is a schematic diagram of the time-dependent change of the supply amount of the synthesis gas supply in 2nd embodiment.

  Preferred embodiments of the present invention will be described below with reference to the accompanying drawings. Such an embodiment is merely an example for facilitating understanding of the invention, and does not limit the present invention unless otherwise specified. In the present specification and drawings, elements having substantially the same functions and configurations are denoted by the same reference numerals, and redundant description is omitted, and elements not directly related to the present invention are not shown.

  (First embodiment)

  FIG. 1 is a schematic diagram of a synthesis gas supply system 100 according to the first embodiment.

  First, the configuration of the synthesis gas supply system 100 will be described.

  The synthesis gas supply system 100 includes four gasification furnaces 10a to 10d, and the gasification furnaces 10a to 10d are connected to the header pipe 12 by gas supply pipes 14a to 14d, respectively.

  Gas supply valves 16 a to 16 d are installed in the gas supply pipes 14 a to 14 d, and the gasification furnace whose operation is stopped is shut off from the header pipe 12 by closing the gas supply valves 16 a to 16 d as necessary. It is possible.

  The header pipe 12 is connected to the first gas user 20A and the second gas user 20B by gas distribution pipes 18A and 18B, and gas distribution valves 22A and 22B are installed in the gas distribution pipes 18A and 18B.

  On the gas distribution pipes 18A and 18B, between the header pipe 12 and the gas distribution valves 22A and 22B, flow rate detection means 24A and 24B for detecting the amount of synthesis gas supplied to each gas user are installed.

  A control device 26 is installed for controlling the opening degree of the gas distribution valves 22A and 22B based on the values detected by the flow rate detection means 24A and 24B.

  Next, the operation of the synthesis gas supply system 100 shown in FIG. 1 will be described.

  First, coal is input to the gasification furnaces 10a to 10d as a raw material for the synthesis gas, and the synthesis gas produced in the gasification furnace is sent to the header pipe 12 through the gas supply pipes 14a to 14d.

  At this time, if there is a gasification furnace being stopped, the gas supply valve is closed and is disconnected from the header pipe 12. In FIG. 1, the gasification furnace 10d is stopped, and the gas supply valve 16d is closed.

  The synthesis gas sent to the header pipe 12 is supplied to the first gas user 20A and the second gas user 20B through the gas distribution pipes 18A and 18B.

  The amount of synthesis gas supplied to each gas user is detected by the flow rate detection means 24A and 24B, and the detection result is sent to the control device 26.

  The control device 26 controls the opening of the gas distribution valves 22A and 22B in accordance with the flow rates detected by the flow rate detection means 24A and 24B, and adjusts the synthesis gas supply amount to each gas user.

  Adjustment of the supply amount of synthesis gas by the control device 26 in the first embodiment will be described with reference to FIG.

  In FIG. 2, the vertical axis represents the supply amount of the synthesis gas, and the horizontal axis represents the time passage of the day.

  2 is the amount of synthesis gas supplied to the first gas user 20A, and that described for USER2 is the amount of synthesis gas supplied to the second gas user 20B. It is a value, which is a value detected by the flow rate detection means 24A and 24B, respectively.

  Changes in the amount of synthesis gas supplied to each gas user over time are sequentially calculated by the control device 26 to calculate a total supply amount.

  The maximum supply amount of the synthesis gas is set in the control device 26 in advance. For example, as shown in FIG. 2, the supply amount of the synthesis gas to the first gas user increases between about 12:00 and 18:00, When the supply amount is likely to exceed the maximum supply amount, the control device 26 performs control to reduce the opening of the gas distribution valve 22B in order to reduce the supply amount of the synthesis gas to the second gas user 20B.

  Thereby, the control device 26 always controls the total supply amount of the synthesis gas to be lower than the maximum supply amount.

  As a result, load fluctuations in the gasification furnace can be kept within a certain range, and shortening of the operation time of the gasification furnace can be prevented.

  Here, a minimum supply amount may be set for each gas user. For example, in a petrochemical plant, a certain amount of load fluctuation can be tolerated. However, when the amount of syngas supplied is below the minimum supply amount, the entire plant may be brought to an emergency stop.

  Therefore, a minimum supply amount is set for each gas user in the control device 26 as necessary.

  For example, in FIG. 2, as a result of an increase in the amount of synthesis gas supplied to the first gas user 20A between about 12:00 and 18:00, supply of the synthesis gas to the second gas user 20B by reducing the opening of the gas distribution valve 22B. If the minimum supply amount for the second gas user 20B is set in the control device 26, the other gas distribution is performed so as not to fall below the minimum supply amount of the synthesis gas for the second gas user 20B. Control is performed to reduce the opening of the valve 22A.

With this control, the synthesis gas supply system 100 according to the first embodiment can suppress the load fluctuation of the gasification furnace as much as possible, and can stabilize the supply amount of the synthesis gas to each gas user without falling below a preset minimum supply amount. As a result, it is possible to supply the synthesis gas.
(Second embodiment)

  FIG. 3 is a schematic diagram of a synthesis gas supply system 200 according to the second embodiment.

  The difference from the first embodiment is that the control device 26 is connected so as to be able to control the amount of synthesis gas produced in each of the gasification furnaces 10a to 10d.

  Adjustment of the supply amount of synthesis gas by the control device 26 in the second embodiment will be described with reference to FIG.

  The vertical and horizontal axes in FIG. 4 are the same as those in FIG. 2, and the difference from FIG. 1 is that the maximum supply amount changes during the day.

  In other words, the control device 26 is set in advance to increase the maximum supply amount only during the summer weekday when the demand for synthesis gas is high, such as the peak time zone during the daytime, and the control device 26 sets the preset time zone. In addition, the maximum supply amount corresponding to the increased production amount is increased at the same time as the control for increasing the production amount of the synthesis gas for the gasification furnaces 10a to 10d having sufficient capacity for the production of the synthesis gas. Let As a result, as much synthesis gas as possible is supplied to each gas user.

  As an example, in FIG. 4, the control device 26 increases the production amount of the synthesis gas to the gasifier in a preset time zone, and at the same time increases the maximum supply amount corresponding to the increase in the production amount, and is increased. Within the range of the maximum supply amount, the control device 26 controls the total supply amount of synthesis gas for each gas user.

  In the synthesis gas supply system 200 according to the second embodiment, the control device 26 controls the production amount of the gasifier, and the synthesis according to the first embodiment is performed except that the maximum supply amount changes during one day. The control is the same as that of the gas supply system 100.

  By this control, the synthesis gas supply system 200 according to the second embodiment increases the operation rate of the gasification furnace as much as possible and stably supplies the synthesis gas to each gas user in addition to the effects of the first embodiment. Has the remarkable effect of being possible.

  The preferred embodiments of the present invention have been described above with reference to the accompanying drawings.

  It will be apparent to those skilled in the art that various changes and modifications can be made within the scope of the claims, and these are naturally within the technical scope of the present invention. Understood.

  The present invention can be used as a synthesis gas supply system for supplying synthesis gas produced from coal as a raw material.

  100: synthesis gas supply system, 200: synthesis gas supply system, 10a to 10d: gasification furnace, 12: header piping, 14a to 14d: gas supply piping, 16a to 16d: gas supply valve, 18A to 18B: gas distribution piping 20A: first gas user, 20B: second gas user, 22A-22B: gas distribution valve, 24A-24B: flow rate detecting means, 26: control device

Claims (4)

A synthesis gas supply system comprising a plurality of gasification furnaces for supplying synthesis gas to a plurality of gas users,
Header piping to which a plurality of the gasification furnaces are connected;
A gas distribution pipe connecting the header pipe and the gas user;
A gas distribution valve installed on the gas distribution pipe;
On the gas distribution pipe, a flow rate detecting means installed between the header pipe and the gas distribution valve,
The flow rate detection means and a control device connected to the gas distribution valve so that the opening degree of the gas distribution valve can be controlled according to the value detected by the flow rate detection means,
When the total supply amount of the synthesis gas detected by the flow rate detection unit is likely to exceed the maximum supply amount of the synthesis gas in a preset time zone, some of the gas distribution valves The total supply amount of the synthesis gas is always controlled to be lower than the maximum supply amount of the synthesis gas, and load fluctuations in the gasification furnace are kept within a certain range. Characteristic synthesis gas supply system.
  When the supply amount of the synthesis gas supplied to the gas user is likely to fall below a preset minimum supply amount for each gas user, the control device connects the gas distribution pipe connected to the other gas user. The synthesis gas supply system according to claim 1, wherein control is performed to reduce the opening of the gas distribution valve. The control device is connected to the gasifier so as to control the amount of synthesis gas produced in the gasifier,
3. The control device according to claim 1, wherein the controller performs control to increase the maximum supply amount at the same time as increasing the synthesis gas production amount from the gasification furnace in a preset time zone. Syngas supply system. The synthesis gas supply system according to any one of claims 1 to 3, wherein the synthesis gas generated in the gasification furnace uses coal as a raw material.

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