Self-heating operation control method based on ARF mode and chemical looping combustion system

Abstract

The invention relates to a self-heating operation control method based on an ARF mode and a chemical looping combustion system, and the method comprises the following steps: 1, obtaining a thermal load instruction requirement, and controlling the fuel feeding amount of a combustion reactor, so that the temperature of the combustion reactor changes along with the increase or decrease of the fuel amount; step 2, if the temperature of the combustion reactor deviates from the set value, increasing or reducing the temperature of the combustion reactor by adjusting the increase or reduction of the circulation flow of the oxygen carrier so as to maintain the temperature of the combustion reactor stable; and step 3, increasing or reducing the temperature of the air reactor by adjusting the increase or reduction of the circulating flow of the oxygen carrier, so that the air reactor synchronously changes along with the change of the combustion reactor, and finally, the thermal load instruction requirement is met. According to the invention, the stable operation of the chemical looping combustion system can be preferentially ensured, and when the load changes, the temperature of the fuel reactor rapidly reaches a stable state, and the self-heating stable operation of the chemical looping combustion system is maintained.

Description

Technical Field

[0001] The present invention belongs to the technical field of chemical chain combustion automatic control, and in particular relates to a self-heating operation control method based on an ARF mode and a chemical chain combustion system. Background Art

[0002] Chemical Looping Combustion (CLC) technology uses an oxygen carrier (OC) made of solid particles of metal oxides, which circulates between an air reactor (AR) and a fuel reactor (FR), transferring oxygen in the air to the fuel reactor in the form of lattice oxygen to react chemically with the fuel. Since the fuel does not come into contact with the air during the entire chemical looping combustion process, the carbon dioxide produced by the combustion will not be diluted by other gases in the air (mainly nitrogen), so the carbon dioxide concentration at the outlet of the fuel reactor can reach more than 90%. There is no need to separate carbon dioxide from other gases and then capture it, so the carbon dioxide produced by the combustion reaction can be captured at low cost and low energy consumption. In summary, chemical looping combustion technology is a new type of combustion technology that can significantly reduce carbon dioxide emissions at low cost under the increasingly urgent situation of dual carbon requirements.

[0003] The oxygen carrier oxidation reaction in AR is an exothermic reaction; the fuel gasification and oxygen carrier reduction reaction in FR is an endothermic reaction. During normal operation, the heat carrying capacity of the oxygen carrier is used to maintain the normal operating temperature of each reactor when circulating between FR and AR.

[0004] At present, most chemical loop devices use external heat sources (natural gas or electric heating) to maintain the temperature of AR and FR reactors to ensure the normal operation of the chemical loop device. Self-heating operation has not been achieved. The core problem is that the thermal balance between FR and AR reactors cannot be controlled. Summary of the invention

[0005] The object of the present invention is to provide a self-heating operation control method and a chemical chain combustion system based on the ARF mode, so as to realize the self-heating operation of the chemical chain combustion system.

[0006] The present invention provides a self-heating operation control method based on the ARF mode, comprising the following steps:

[0007] Step 1, obtaining heat load instruction requirements, controlling the fuel feed amount of the combustion reactor, so that the temperature of the combustion reactor changes with the increase or decrease of the fuel amount;

[0008] Step 2, if the temperature of the combustion reactor deviates from the set value, the temperature of the combustion reactor is increased or decreased by adjusting the circulation flow rate of the oxygen carrier to maintain the stability of the temperature of the combustion reactor;

[0009] Step 3, by adjusting the increase or decrease of the circulation flow rate of the oxygen carrier, the temperature of the air reactor is increased or decreased, so that the air reactor changes synchronously with the changes of the combustion reactor, and finally meets the heat load instruction requirements.

[0010] Furthermore, in step 1, the heat load controller obtains the heat load instruction requirement and issues a control instruction.

[0011] Furthermore, in step 1, the fuel control valve obtains the control instruction issued by the heat load controller to control the fuel feed amount of the combustion reactor.

[0012] Furthermore, in step 2, the fuel reactor temperature controller determines whether the temperature of the combustion reactor deviates from the set value, and if so, issues a control instruction.

[0013] Furthermore, in step 2, the oxygen carrier circulation flow control valve obtains the control instruction issued by the fuel reactor temperature controller to adjust the increase or decrease of the oxygen carrier circulation flow.

[0014] Furthermore, in step 1, when the heat load instruction is 4 MWth, the fuel feed rate is 0.8-1.2 t / h.

[0015] Furthermore, in step 2, the temperature setting value of the fuel reactor is 950° C., the flow rate is maintained at 1.5-2.5 m / s, the circulation flow rate of the oxygen carrier is 150-200 t / h, and the flow rate is maintained at 9-10 m / s.

[0016] The present invention also provides a chemical chain combustion system, comprising a combustion reactor, an air reactor, a heat load controller, a fuel control valve, a fuel reactor temperature controller, and an oxygen carrier circulation flow control valve; the heat load controller is connected to the combustion reactor through the fuel control valve; the combustion reactor and the air reactor are connected through the oxygen carrier circulation flow control valve; the combustion reactor is connected to the oxygen carrier circulation flow control valve through the fuel reactor temperature controller;

[0017] The heat load controller is used to obtain heat load instruction requirements and issue control instructions;

[0018] The fuel control valve is used to obtain the control instruction issued by the heat load controller, control the fuel feed amount of the combustion reactor, and make the temperature of the combustion reactor change with the increase or decrease of the fuel amount;

[0019] The fuel reactor temperature controller is used to determine whether the temperature of the combustion reactor deviates from the set value, and if so, to issue a control instruction;

[0020] The oxygen carrier circulation flow control valve is used to obtain the control instruction issued by the fuel reactor temperature controller, adjust the increase or decrease of the oxygen carrier circulation flow, increase or decrease the temperature of the combustion reactor, so as to maintain the stability of the combustion reactor temperature;

[0021] The oxygen carrier circulation flow control valve is also used to increase or decrease the temperature of the air reactor while adjusting the oxygen carrier circulation flow, so that the air reactor changes synchronously with the changes of the combustion reactor and finally meets the heat load instruction requirements.

[0022] Furthermore, the heat load controller adopts a proportional-integral controller.

[0023] Furthermore, the fuel reactor temperature controller adopts a proportional-integral controller.

[0024] Through the above scheme, a self-heating operation control method based on the ARF mode and a chemical chain combustion system can give priority to ensuring the stable operation of the chemical chain combustion system, and when the load changes, the temperature of the fuel reactor can quickly reach a stable state to maintain the self-heating stable operation of the chemical chain combustion system. In addition, the load response speed under the tracking mode can utilize the heat storage of the fuel reactor, and within the allowable fluctuation range of the fuel reactor temperature, according to the heat storage of the fuel reactor, undertake the rapid adjustment of part of the load.

[0025] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention and implement it according to the contents of the specification, the following is a detailed description of the preferred embodiments of the present invention in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a flow chart of a self-heating operation control method based on the ARF mode of the present invention;

[0027] Figure 2 It is a structural diagram of the chemical loop combustion system of the present invention. DETAILED DESCRIPTION

[0028] The specific implementation of the present invention is further described in detail below in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0029] Ginseng Figure 1As shown, this embodiment provides a self-heating operation control method based on ARF (Air Reactor Follow Mode, ARF, air reactor tracking mode), comprising the following steps:

[0030] Step S1, obtaining a heat load instruction requirement, controlling the fuel feed amount of the combustion reactor, so that the temperature of the combustion reactor changes with the increase or decrease of the fuel amount;

[0031] Step S2, if the temperature of the combustion reactor deviates from the set value, the temperature of the combustion reactor is increased or decreased by adjusting the circulation flow rate of the oxygen carrier to maintain the stability of the temperature of the combustion reactor;

[0032] Step S3, by adjusting the increase or decrease of the circulating flow rate of the oxygen carrier, the temperature of the air reactor is increased or decreased, so that the air reactor changes synchronously with the changes of the combustion reactor, and finally meets the heat load instruction requirements.

[0033] In a specific example, an adjustment instruction is output according to the deviation between the set value and the actual value, and the relevant parameters are as follows: when the heat load instruction is 4MWth, the fuel feed rate is 0.8-1.2t / h, the fuel reactor temperature setting value is 950°C, the flow rate is maintained at 1.5-2.5m / s, the oxygen carrier circulation flow rate is 150-200t / h, and the flow rate is maintained at 9-10m / s.

[0034] Ginseng Figure 2 As shown, this embodiment also provides a chemical looping combustion system, wherein:

[0035] LOAD: heat load

[0036] LS: Heat load command

[0037] LC: Thermal load controller (proportional integral controller)

[0038] FL_V: Fuel control valve

[0039] FRS: Fuel Reactor Temperature Setpoint

[0040] TC: Fuel Reactor Temperature Controller (Proportional Integral Controller)

[0041] OC_V: Oxygen carrier circulation flow control valve

[0042] FR: Combustion Reactor

[0043] AR: Air Reactor.

[0044] The heat load controller is connected to the combustion reactor through the fuel control valve; the combustion reactor and the air reactor are connected through the oxygen carrier circulation flow control valve; the combustion reactor is connected to the oxygen carrier circulation flow control valve through the fuel reactor temperature controller;

[0045] The heat load controller is used to obtain heat load instruction requirements and issue control instructions;

[0046] The fuel control valve is used to obtain the control instruction issued by the heat load controller, control the fuel feed amount of the combustion reactor, and make the temperature of the combustion reactor change with the increase or decrease of the fuel amount;

[0047] The fuel reactor temperature controller is used to determine whether the temperature of the combustion reactor deviates from the set value, and if so, to issue a control instruction;

[0048] The oxygen carrier circulation flow control valve is used to obtain the control instruction issued by the fuel reactor temperature controller, adjust the increase or decrease of the oxygen carrier circulation flow, increase or decrease the temperature of the combustion reactor, so as to maintain the stability of the combustion reactor temperature;

[0049] The oxygen carrier circulation flow control valve is also used to increase or decrease the temperature of the air reactor while adjusting the oxygen carrier circulation flow, so that the air reactor changes synchronously with the changes of the combustion reactor and finally meets the heat load instruction requirements.

[0050] First, according to the heat load instruction (LS), the heat load controller (LC) issues an instruction to control the fuel feed amount of the FR by adjusting the fuel control valve (FL_V). The temperature of the FR will change as the amount of fuel increases or decreases.

[0051] At this time, the fuel reactor temperature controller (TC) continuously changes the opening of the oxygen carrier circulation flow control valve (OC_V) according to the size of the FR temperature deviation from the set value (FRS), and adjusts the increase or decrease of the oxygen carrier circulation flow to maintain the stability of the FR temperature.

[0052] The increase or decrease of the oxygen carrier circulation flow rate will increase or decrease the temperature of the AR, thereby adapting to the needs of the heat load instruction and ultimately meeting the heat load instruction requirements.

[0053] It can be seen that this control method is to first let FR track the needs of the external load, and then make AR change synchronously with the changes of FR. Therefore, it is called the "air reactor following" control method.

[0054] Through this control method, the chemical chain combustion system can be guaranteed to operate smoothly, and when the load changes, the temperature of the fuel reactor can quickly reach a stable state, maintaining the self-heating stable operation of the chemical chain combustion system. In addition, the load response speed under this tracking mode can utilize the heat storage of the fuel reactor, and within the allowable fluctuation range of the fuel reactor temperature, according to the heat storage of the fuel reactor, undertake the rapid adjustment of part of the load.

[0055] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. It should be pointed out that a person skilled in the art can make several improvements and modifications without departing from the technical principles of the present invention, and these improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. A self-heating operation control method based on ARF mode, characterized in that: The steps include: Step 1, obtaining heat load instruction requirements, controlling the fuel feed amount of the combustion reactor, so that the temperature of the combustion reactor changes with the increase or decrease of the fuel amount; Step 2, if the temperature of the combustion reactor deviates from the set value, the temperature of the combustion reactor is increased or decreased by adjusting the circulation flow rate of the oxygen carrier to maintain the stability of the temperature of the combustion reactor; Step 3, by adjusting the increase or decrease of the circulation flow rate of the oxygen carrier, the temperature of the air reactor is increased or decreased, so that the air reactor changes synchronously with the changes of the combustion reactor, and finally meets the heat load instruction requirements.

2. The self-heating operation control method based on the ARF mode according to claim 1 is characterized in that: In step 1, the heat load controller obtains the heat load instruction requirement and issues a control instruction.

3. The self-heating operation control method based on ARF mode according to claim 2 is characterized in that: In step 1, the fuel control valve obtains the control instruction issued by the heat load controller to control the fuel feed amount of the combustion reactor.

4. The self-heating operation control method based on the ARF mode according to claim 3 is characterized in that: In step 2, the fuel reactor temperature controller determines whether the temperature of the combustion reactor deviates from the set value, and if so, issues a control instruction.

5. The self-heating operation control method based on ARF mode according to claim 4 is characterized in that: In step 2, the oxygen carrier circulation flow control valve obtains the control instruction issued by the fuel reactor temperature controller to adjust the increase or decrease of the oxygen carrier circulation flow.

6. The self-heating operation control method based on ARF mode according to claim 1 is characterized in that: In step 1, when the heat load instruction is 4MWth, the fuel feed rate is 0.8-1.2t / h.

7. The self-heating operation control method based on ARF mode according to claim 6 is characterized in that: In step 2, the temperature setting value of the fuel reactor is 950° C., the flow rate is maintained at 1.5-2.5 m / s, the circulation flow rate of the oxygen carrier is 150-200 t / h, and the flow rate is maintained at 9-10 m / s.

8. A chemical looping combustion system, characterized in that: It includes a combustion reactor, an air reactor, a heat load controller, a fuel control valve, a fuel reactor temperature controller, and an oxygen carrier circulation flow control valve; the heat load controller is connected to the combustion reactor through the fuel control valve; the combustion reactor and the air reactor are connected through the oxygen carrier circulation flow control valve; the combustion reactor is connected to the oxygen carrier circulation flow control valve through the fuel reactor temperature controller; The heat load controller is used to obtain heat load instruction requirements and issue control instructions; The fuel control valve is used to obtain the control instruction issued by the heat load controller, control the fuel feed amount of the combustion reactor, and make the temperature of the combustion reactor change with the increase or decrease of the fuel amount; The fuel reactor temperature controller is used to determine whether the temperature of the combustion reactor deviates from the set value, and if so, to issue a control instruction; The oxygen carrier circulation flow control valve is used to obtain the control instruction issued by the fuel reactor temperature controller, adjust the increase or decrease of the oxygen carrier circulation flow, increase or decrease the temperature of the combustion reactor, so as to maintain the stability of the combustion reactor temperature; The oxygen carrier circulation flow control valve is also used to increase or decrease the temperature of the air reactor while adjusting the oxygen carrier circulation flow, so that the air reactor changes synchronously with the changes of the combustion reactor and finally meets the heat load instruction requirements.

9. The chemical looping combustion system according to claim 8, characterized in that: The heat load controller adopts a proportional-integral controller.

10. The chemical looping combustion system according to claim 9, characterized in that: The fuel reactor temperature controller adopts a proportional-integral controller.

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