SOC system preheating device with circulation loop and preheating system

Abstract

The utility model belongs to the technical field of new energy, and relates to an SOC system preheating device with a circulation loop and a preheating system, the preheating device comprises a main body and a circulation pipeline; the main body is provided with a hollow cavity which is provided with an inlet and an outlet; an electric heater is arranged on the side, close to the inlet, of the hollow cavity, and a catalytic burner is arranged on the side, close to the outlet, of the hollow cavity. The hollow cavity is connected with an oxidant metering device through an inlet, and a fuel inlet is formed in the side face of the main body and connected with a fuel flow meter; the circulating pipeline is connected to the side face of the main body, and the circulating pipeline and the hollow cavity of the main body form a parallel branch used for conveying gas exhausted from the outlet to the front end of the hollow cavity in a backflow mode. A gas oxidizing agent is input through the metering device, heated by the electric heater and then mixed with fuel, exhausted gas can circularly flow back to be electrically heated with newly-fed gas again, and the purposes of effectively utilizing mixed heating and reducing the electric heating power requirement of the system are achieved.

Description

Technical Field

[0001] The utility model relates to the technical field of new energy, in particular to a SOC system preheating device and a preheating system with a circulation loop, belonging to the technical field of solid oxide fuel cells. Background Art

[0002] Solid Oxide Fuel Cells (SOFC) is a new power generation technology that directly converts the chemical energy of fuel into electrical energy through electrochemical reactions. The operating temperature of the SOFC system is between 650℃-800℃, the power generation efficiency can reach more than 60%, and the combined heat and power efficiency can reach more than 90%. In addition, SOFC only produces water and high-temperature exhaust gas during power generation, without harmful emissions. It is a new clean energy conversion technology.

[0003] The SOFC system is mainly composed of evaporator, reformer, heat box, stack, burner, heat exchanger, waste heat recovery system, inverter and other components. The evaporator mainly produces water vapor to provide water vapor for steam reforming of hydrocarbon fuels; the reformer mainly reforms the hydrocarbon fuels such as natural gas and alcohols entering the system and water vapor into synthesis gas containing hydrogen, carbon monoxide and carbon dioxide, so that it is more conducive to electrochemical reaction when entering the stack; the heat box mainly provides a place for the stack to install and keep it warm to maintain the working environment temperature of the stack; the burner mainly performs secondary conversion on the unreacted fuel entering the stack to improve the fuel utilization rate of the system; the heat exchanger exchanges heat and uses high-temperature heat sources to heat low-temperature media, such as preheating fuel gas, preheating air, heating water for heating, etc., to improve the energy utilization rate of the system.

[0004] In the prior art, the temperature of the heat box is mainly raised by preheating with electric heating or flame burners, and these two methods have different disadvantages.

[0005] When all electric heating is used, the power consumption is particularly large, and a relatively large electric heating power is required. The heating rate is significantly affected by the electric heating device. When SOFC is heated by electric heating, the heat loss during the heating process must be considered. If the heating power is insufficient, it may take a long time for the SOFC to reach the operating temperature by electric heating, which limits the SOFC's rapid startup and response capabilities.

[0006] When using a flame burner to generate high-temperature gas to heat the hot box, there are certain safety risks and it is not suitable for use in flammable and explosive places. In addition, it is difficult to accurately control the temperature when heating with open flames, and it is difficult to meet the requirements for situations where precise temperature control is required. Combustion heating also produces CO, NO x and CH xToxic and harmful pollutants such as chlorinated polyethylene may cause the risk of poisoning and suffocation when used in a closed environment.

[0007] Electric heating for air intake heating of test systems or SOEC also consumes a lot of electricity. Utility Model Content

[0008] The purpose of the utility model is to overcome the shortcomings of the prior art method of heating the hot box or preheating the intake air by electric heating, which has high energy consumption and requires a high-power heating source, and to provide an efficient preheating device and method for a SOC (Solid Oxide Cells) system.

[0009] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0010] A SOC system preheating device with a circulation loop, the preheating device comprising a main body and a circulation pipeline; the main body has a hollow cavity, and the hollow cavity has an inlet and an outlet;

[0011] An electric heater is provided on one side of the hollow cavity close to the inlet, and a catalytic burner is provided on one side of the hollow cavity close to the outlet;

[0012] The hollow cavity is connected to the oxidant metering device through the inlet.

[0013] A fuel inlet is provided on the side of the main body, and the fuel inlet is connected to a fuel flow meter;

[0014] The circulation pipeline is arranged and connected to the side of the main body, and the circulation pipeline and the hollow cavity of the main body form a parallel branch for refluxing the gas discharged from the outlet to the front end of the hollow cavity.

[0015] The preheating device of the SOC system of the utility model can accurately control the flow rate of the input gas oxidant, use the electric heater to heat and raise the temperature, and the outlet is connected to the circulation pipeline to form a loop, so that the gas discharged from the outlet can circulate back to the inlet, transfer its own high temperature to the newly entered gas oxidant, and then be heated and raised by the electric heater again. Only a small electric heater power is needed to achieve the goal of preheating the gas at a higher temperature.

[0016] The preheating device of the SOC system of the utility model can quickly heat up the oxidant gas, complete the startup work of the preheating device, and reduce the demand for high-power electric energy. The temperature of the gas passing through the electric heater is increased by partial circulation of the gas to be preheated, so that the mixed gas passing through the electric heater can be raised to a higher temperature (such as the fuel combustion temperature), and then the fuel gas is added for catalytic combustion. The gas has no pollution risk, the chemical reaction between the oxidant and the fuel releases a large amount of heat, and the temperature can be accurately controlled. When achieving the purpose of the SOC fast preheating device, the heat supply of the downstream heat-using device is effectively realized, and the energy utilization efficiency is improved.

[0017] Furthermore, it also includes a T1 temperature sensor and a T2 temperature sensor, wherein the T1 temperature sensor is arranged in the hollow cavity and before the catalytic burner; the T2 temperature sensor is arranged after the catalytic burner or at the outlet of the hollow cavity.

[0018] Setting T1 temperature sensor and T2 temperature sensor to detect the gas temperature before and after the catalytic burner respectively can accurately control the combustion of the mixed gas in the catalytic burner. The T1 temperature sensor detects the gas temperature before the catalytic burner to determine whether the mixed gas has reached the ignition temperature of the catalytic burner, avoiding insufficient oxidation reaction caused by failure to reach the fuel ignition temperature. When the T1 temperature sensor detects that the gas temperature has reached the ignition temperature, monitoring the temperature of the T2 temperature sensor can know the heat release of the mixed gas in the catalytic burner. After determining that the target temperature of the hot box heating is met, the heating power can be appropriately adjusted to control the temperature of the final discharged mixed gas to meet application needs.

[0019] Furthermore, the preheating device also includes a controller, and the controller is connected to at least one of the oxidant metering device, the electric heater, the fuel flow meter, the T1 temperature sensor and the T2 temperature sensor.

[0020] Preferably, the controller is connected to the oxidant metering device, the electric heater, the fuel flow meter, the T1 temperature sensor and the T2 temperature sensor. Based on the temperature values ​​determined by each temperature sensor, the heating power of the electric heater or the gas flow of the oxidant metering device and the fuel flow meter is adjusted by feedback.

[0021] Furthermore, the oxidant metering device is an independent flow meter or a delivery device capable of measuring the volume of delivered gas. For example, when an external pressure vessel is used, a flow meter dedicated to the pressure vessel is used; when a pressure vessel is not used, such as air supply, a blower capable of metering can be used to determine the delivered air oxidant flow rate by measuring the delivered gas volume.

[0022] Furthermore, the oxidant is a gaseous oxidant, and the preferred oxidant is air or pure oxygen, preferably air. The oxidant metering device is used to meter the oxidant flow entering the preheating device, and the oxidant is preferably air, but can also be pure oxygen; when air is used, the gas is easy to obtain and is relatively safe.

[0023] Furthermore, the electric heater is a resistance wire heater or a ceramic heater. Preferably, the electric heater is a low voltage DC electric heater with a voltage less than 48V, which improves safety and portability of power supply.

[0024] Furthermore, a spoiler is also provided in the hollow cavity, and the spoiler is located after the electric heater and before the catalytic burner. The spoiler makes the gas passing through the electric heater form a turbulent state, increases the turbulence inside the gas, and then fully mixes with the fuel gas input into the hollow cavity from the fuel inlet, so that the oxidation reaction in the catalytic burner releases heat completely, and increases the temperature of the mixed gas.

[0025] Furthermore, the spoiler is at least one of a metal mixer, a honeycomb structure carrier, and a metal carrier.

[0026] Furthermore, a mixer is also provided in the hollow cavity, and the mixer is located after the fuel inlet.

[0027] The mixer is arranged after the fuel inlet to fully mix the oxidant and the fuel. The mixer further improves the mixing uniformity and temperature uniformity of the oxidant and the fuel, and promotes the full oxidation reaction of the mixed gas in the catalytic burner.

[0028] Furthermore, the mixer is a honeycomb structure carrier or other mixer suitable for mixing two or more gases.

[0029] Furthermore, it also includes an ejector reflow device, which is located at the inlet of the hollow cavity and after the oxidant metering device; the ejector reflow device is connected to the circulation pipeline.

[0030] Furthermore, the catalytic burner is provided with a precious metal coating, preferably, the precious metal coating is at least one of platinum, palladium, rhodium, etc. Precious metals can catalyze the oxidation reaction of hydrocarbon fuels at a certain temperature, such as H2+O2→H2O; CH4+O2→CO2+H2O; CO+O2→CO2, etc. The catalytic burner catalytically oxidizes the mixed gas to further increase the temperature of the mixed gas.

[0031] Furthermore, the catalytic burner is a honeycomb structure carrier, preferably a metal carrier. The precious metal is loaded on the honeycomb structure carrier to better play the role of catalytic oxidation reaction.

[0032] Furthermore, the surface of the preheating device for the SOC system has a thermal insulation layer.

[0033] Preferably, the surface of the main body has a heat-insulating layer.

[0034] Preferably, the surface of the circulation pipeline has a heat-insulating layer.

[0035] Furthermore, one end of the circulation pipeline is connected to the ejector reflow device, and the other end is connected to the outlet of the hollow cavity.

[0036] Furthermore, a circulation valve is provided on the circulation pipeline. By providing the circulation valve on the circulation pipeline to form a circulation subsystem, the circulation state opening / closing, the circulation flow size or the circulation flow ratio can be accurately controlled.

[0037] Furthermore, the surface of the main body has a heat-insulating layer.

[0038] A preheating system for a SOC system comprises the above-mentioned preheating device, wherein the outlet of the preheating device is connected to a SOC heat box. By connecting the end of the preheating device to the heat box, the high-temperature gas passing through the preheating device directly enters the heat box and is used as a heat source for the heat box.

[0039] Furthermore, a T5 temperature sensor is provided inside the SOC heat box, and the T5 temperature sensor is used to detect the temperature inside the heat box.

[0040] Further, the T5 temperature sensor is connected to the controller.

[0041] Furthermore, the surface of the heat box has a heat-insulating layer, which reduces heat loss and improves energy utilization.

[0042] Compared with the prior art, the utility model has the following beneficial effects:

[0043] 1. The preheating device of the utility model for the SOC system is formed by combining electric heating with catalytic combustion to form a compact preheating device, and is matched with a circulation pipeline. A smaller electric heater can be used to preheat the oxidant, avoiding the high cost and high power consumption of high-power electric heaters. The preheating device can be started with a smaller electric power, effectively reducing the impact of the preheating device on the power system.

[0044] 2. The utility model is used for the preheating device of the SOC system. Since the power consumption is lower, there is no need for a dedicated high-power circuit, and the ignition work of the preheating device can be completed using the mains electricity.

[0045] 3. The preferred solution of the preheating device of the utility model for the SOC system adopts the method of internally arranging a spoiler and a mixer to promote the uniformity of gas mixing, improve the uniformity of mixing of the combustible gas and the oxidant (such as oxygen), and make the oxidation heat release more complete.

[0046] 4. The preheating device for the SOC system of the utility model can connect multiple temperature sensors to the controller. The control method provided by the controller is simple and easy to control the target temperature.

[0047] 5. The preferred solution of the preheating device of the utility model is to set an ejector reflow device, which is located at the entrance of the hollow cavity, and automatically completes the reflow by using the air inlet of the system, without the need for an additional power device, and the preheating device has higher reliability. In addition, in the initial stage of system operation, by recycling part of the gas, the dependence on electric heating power can be further reduced, and the heat of part of the exhaust gas can be reused for a second time, so as to quickly reach the target temperature. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1 It is a structural schematic diagram of the preheating device of the utility model.

[0049] Figure 2 It is a system schematic diagram of the connection between the preheating device and the heat box of the utility model.

[0050] Figure 3 It is a schematic diagram of a control system based on an adaptive control method according to Example 1.

[0051] Figure 4 This is a schematic diagram of a control system based on an adaptive control method according to Example 3.

[0052] Markings in the figure:

[0053] 100-main body, 101-oxidant metering device, 102-electric heater, 103-turbulator, 104-fuel flow meter, 105-fuel inlet, 106-mixer, 107-T1 temperature sensor, 108-catalytic burner, 109-T2 temperature sensor, 110-outlet, 111-circulation valve, 112-circulation pipeline, 113-injector reflow device, 200-SOC hot box, 201-T5 temperature sensor. DETAILED DESCRIPTION

[0054] The utility model is further described in detail below in conjunction with test examples and specific implementation methods.

[0055] In the description of the specific embodiments of the present invention, unless otherwise specified, the terms indicating the orientation or position relationship such as "upper", "lower", "left", "right", "center", "inside", "outside", etc. are all expressions based on the orientation or position relationship shown in the drawings, or the orientation or position relationship when the product / equipment / device of the utility model is usually used. These terms of orientation or position relationship are only for the convenience of describing the scheme of the utility model or simplifying the description in the specific embodiments, so that technicians can quickly understand the scheme, rather than indicating or implying that a specific device / component / element must have a specific orientation, or be constructed and operated in a specific position relationship, and therefore cannot be understood as a limitation on the present invention.

[0056] The front and back in the present invention are described based on the gas flow direction in the preheating device, with the air inlet end of the main body as the "front" and the air outlet end as the "back", just to facilitate the description of the preheating device of the present invention and is not a fixed direction limitation.

[0057] In addition, if the terms "horizontal", "vertical", "overhanging", "parallel" and the like appear, it does not mean that the corresponding devices / components / elements are required to be absolutely horizontal or vertical or overhanging or parallel, but may be slightly tilted or have deviations. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but may be slightly tilted. Alternatively, it can be simplified to mean that the corresponding devices / components / elements are set in directions such as "horizontal", "vertical", "overhanging", "parallel", etc., and can have an error / deviation of ±10% relative to the corresponding direction setting, more preferably an error / deviation within ±8%, more preferably an error / deviation within ±6%, more preferably an error / deviation within ±5%, and more preferably an error / deviation within ±4%. As long as the corresponding device / component / element is within the error / deviation range, it can still achieve its role in the solution of the utility model.

[0058] In addition, the expressions “first”, “second”, “third”, etc., which appear in the terms, are merely used to distinguish the description of the same or similar components and should not be understood as emphasizing or implying the relative importance of specific components.

[0059] In addition, in the description of the embodiments of the present invention, "several", "multiple" and "a number" represent at least 2. It can be any number such as 2, 3, 4, 5, 6, 7, 8, 9, and even more than 9.

[0060] In addition, in the description of the technical solution of the utility model, unless otherwise clearly specified / defined / restricted, the terms "set", "install", "connect", "connected", "provided with", "laid", and "arranged" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection, and can be welding, riveting, bolting, threading, and other commonly used connection means in the field. This connection can be a mechanical connection, an electrical connection, or a communication connection; it can be a direct connection, or an indirect connection through an intermediate medium, and it can be the internal communication of two components.

[0061] Example 1

[0062] like Figure 1 A preheating device for a SOC system is shown, the preheating device includes a main body 100 and a circulation pipeline 112; the main body has a hollow cavity, and the hollow cavity has an inlet and an outlet; an electric heater 102 is arranged on the side of the hollow cavity close to the inlet, and a catalytic burner 108 is arranged on the side of the hollow cavity close to the outlet; the hollow cavity is connected to an oxidant metering device 101 through the inlet, and a fuel inlet 105 is arranged on the side of the main body, and the fuel inlet 105 is provided with a pipeline extending into the hollow cavity, and the fuel inlet is connected to a fuel flow meter 104; the circulation pipeline 112 is arranged and connected to the side of the main body, and the circulation pipeline and the hollow cavity of the main body form a parallel branch for refluxing the gas discharged from the outlet to the front end of the hollow cavity.

[0063] Furthermore, a circulation valve 111 is provided on the circulation pipeline 112 , and the circulation valve 111 is arranged near the outlet of the main body to reduce the retention of exhaust gas from the catalytic burner 108 in the circulation pipeline 112 .

[0064] If the temperature of the mixed gas after passing through the catalytic burner 108 does not reach the predetermined temperature (such as the fuel ignition temperature), it can be circulated to allow the gas to circulate to the inlet and be heated by the electric heater again, thereby reducing the power limit on the electric heater 102 and achieving the heating target with less power.

[0065] The circulation pipeline 112 forms a circulation subsystem on the side of the main body. The preferred solution is to set an ejector reflow device 113 at the main body inlet, and connect the oxidant metering device to the front end (i.e., the air inlet) of the ejector reflow device 113; the ejector reflow device 113 is located between the oxidant metering device 101 and the electric heater 102; one end of the circulation pipeline 112 is connected to the rear pipeline of the catalytic burner 108, and the other end is connected to the ejector reflow device 113. The circulation subsystem refluxes the gas at the outlet of the main body, and re-enters the hollow cavity of the main body to be heated again by the electric heater.

[0066] Furthermore, this embodiment is a preheating device for a SOC test system, and a thermal insulation layer is provided on the surface of the main body and / or the circulation pipeline to further reduce heat loss and improve energy utilization.

[0067] Furthermore, it also includes temperature sensors: T1 temperature sensor 107 and T2 temperature sensor 109 , which are respectively arranged before and after the catalytic burner 108 to detect the temperature of the mixed gas entering and exiting the catalytic burner 108 .

[0068] Furthermore, it also includes a controller TCU, such as Figure 3 As shown, the controller TCU is connected to the oxidant metering device M.F1, the electric heater, the fuel flow meter M.F2, the T1 temperature sensor and the T2 temperature sensor. Based on the temperature values ​​determined by each temperature sensor, the heating power of the electric heater or the gas flow of the oxidant metering device and the fuel flow meter is adjusted by feedback.

[0069] Table 1

[0070]

[0071] (1) The temperature controller system is powered on and self-checked. After the self-check passes, the fuel type Fi and preheating target temperature T are input. T ; The system automatically obtains the ignition temperature T according to the calibration parameters Fi , the flow control value of M.F1 is Q1, and the flow control value of M.F2 is Q2.

[0072] (2) After inputting and obtaining the relevant parameters, the oxidant metering device 101 is turned on and air is input according to the flow control value Q1 of M.F1; operation is started at the flow rate of Q1, and the heater 102 starts working.

[0073] (3) The controller TCU is connected to the T1 temperature sensor 107 and the T2 temperature sensor 109. The TCU detects the T1 temperature in real time and adjusts the air flow Q1 according to the T1 temperature until the T1 temperature rises to the ignition temperature T Fi Alternatively, the circulation pipeline 112 is opened to allow the rear gas to circulate back to the front and be heated by the electric heater 102 again until T1 can be heated to the ignition temperature T Fi Or the above two methods can be combined to achieve effective heating to reach the target temperature value.

[0074] (4) When T1>T Fi After that, the fuel flow meter 104 starts to work and starts to operate according to the flow rate set value Q2 of the M.F2 flow meter.

[0075] (5) Real-time detection of T2 temperature sensor 109 to obtain T2 temperature, and adjust the value of Q2 according to T2 temperature until T2 ≥ preheating target temperature T T After adjusting the flow rate of Q2, adjust the flow rate of Q1 to match the amount of oxygen required for complete combustion of the fuel.

[0076] Preferably, the system further includes step (6): performing over-temperature protection during system operation, and the (temperature) controller TCU performs over-temperature protection according to T1-T Fi >X1, conduct feedback adjustment of Q1, according to T2-T T > X2, and conduct feedback adjustment of Q2. Among them, X1 and X2 can be revised and adjusted, and the corresponding control is automatically adjusted according to the heating effect of the preheating module.

[0077] Example 2

[0078] like Figure 1 As shown, a preheating device for a SOC system is similar to the preheating device of Example 1, except that it also includes a spoiler 103 and a mixer 106. The spoiler 103 uses a metal mixer. It should be known that those skilled in the art can also choose a honeycomb structure carrier or a metal carrier. The mixer 106 uses a honeycomb structure carrier.

[0079] The oxidant metering device 101 in the preheating device can use a dedicated flow meter when an external pressure vessel is connected; it can also use a blower capable of metering to supply air.

[0080] The catalytic burner 108 uses a metal honeycomb structure carrier, and the carrier carries precious metal platinum as a combustion catalyst.

[0081] The electric heater 102 is a low voltage DC resistance heater of less than 48 V. It should be known that those skilled in the art may also choose a ceramic heater to improve safety and portability of power supply.

[0082] The following uses methane to heat air as an example to explain in detail the process principle of the high-efficiency preheating device 100 of this embodiment.

[0083] The air is metered into the preheating device 100 through the M.F1 oxidant metering device 101 (according to the experimental needs, those skilled in the art can replace it with other oxidants such as pure oxygen or industrial oxygen). After the air enters the hollow cavity of the main body, it flows through the electric heater 102 and is heated and heated by the electric heater 102. Then, the heated air flows through the spoiler 103, performs turbulent flow, and increases the turbulence inside the air. Then, the fuel inlet 105 arranged behind the spoiler 103 inputs methane (fuel) into the internal cavity of the shell. Because the spoiler 103 increases the turbulence of the air, the mixing effect of methane and air coming in from the fuel inlet 105 is better.

[0084] Then, the mixed gas flows through the mixer 106 to further improve the mixing uniformity and temperature uniformity. Then, the mixed gas enters the catalytic burner 108, which catalytically burns the mixed gas and releases heat through the oxidation reaction to increase the temperature of the mixed gas. The catalytic burner 108 of this embodiment uses a catalytic burner coated with precious metal coatings such as platinum, palladium, and rhodium to catalyze the oxidation reaction of hydrocarbon fuels, such as H2+O2→H2O; CH4+O2→CO2+H2O; CO+O2→CO2, etc.

[0085] The T1 temperature sensor 107 and the T2 temperature sensor 109 detect the gas temperature before and after the catalytic burner 108. When the temperature does not reach the ignition temperature of the fuel gas, the circulation valve is opened to allow the gas at the outlet of the hollow cavity to flow back to the inlet and be heated again by the electric heater.

[0086] The preheating device includes a controller, which is connected to the oxidant metering device, the electric heater, the fuel flow meter, the T1 temperature sensor and the T2 temperature sensor. Based on the temperature values ​​determined by each temperature sensor, the heating power of the electric heater or the gas flow of the oxidant metering device and the fuel flow meter is adjusted by feedback. The specific schematic diagram is as follows Figure 3 shown.

[0087] The control logic of the high-efficiency preheating device 100 using methane and heated air as a mixed heat source adopts an adaptive control method: TCU is a temperature controller for the high-efficiency preheating device; the flow rate of M.F1 is expressed as Q1 (the gas flow rate of the oxidant metering device 101), and the flow rate of M.F2 is expressed as Q2 (the fuel flow rate of the fuel flow meter 104). The system input parameters are: fuel type Fi and the corresponding fuel ignition temperature T obtained by looking up the table Fi , the real-time detection reaches the ignition temperature value T1, the preheating target temperature T T , temperature steps X1, X2, air flow Q1, fuel flow Q2, circulation line flow Q3, enter the relevant system calibration parameters and target parameters according to the table below.

[0088] Table 2

[0089]

[0090] (1) The temperature controller system is powered on and self-checked. After the self-check passes, the fuel type Fi and preheating target temperature T are input. T ; The system automatically obtains the ignition temperature T according to the calibration parameters Fi The flow control value of M.F1 is Q1, and the flow control value of M.F2 is Q 2、 The circulation pipeline controls the flow Q3.

[0091] (2) After inputting and obtaining the relevant parameters, the oxidant metering device 101 is turned on and air is input according to the flow control value Q1 of M.F1; operation is started at the flow rate of Q1, and the heater 102 starts working.

[0092] (3) Real-time detection of temperature T1, after stabilization for 5-30 minutes, if T1 < T Fi , gradually reduce the air flow Q1 with a fixed step size until T1 ≥ T Fi Alternatively, the circulation valve 111 is opened so that the circulation pipeline 112 circulates part of the tail gas to the inlet, thereby increasing the inlet gas temperature until T1 ≥ T Fi It can also be a combination of the above two methods, so that T1 ≥ T Fi .

[0093] (4) When T1 ≥ T Fi After that, the fuel gas is supplied at the flow rate of Q2; the temperature T2 is detected in real time, and after stabilization for 5-30 minutes, if T2 < T T , gradually increase the fuel flow Q2 with a fixed step size until T2 ≥ T T When T1 ≥ T Fi , adaptively adjust the Q3 flow in the circulation pipeline until T2 ≥ T T After adjusting the flow rate of Q2, adjust the flow rate of Q1 synchronously to match the amount of oxygen required for complete combustion of the fuel.

[0094] (5) Over-temperature safety protection, when T1-T Fi >X1, reduce Q1 with a fixed step size; when T2-T2 T >X2, decrease Q2 with a fixed step size.

[0095] Example 3

[0096] like Figure 2 As shown, the same preheating device as in Example 2 is connected to the heat box to form a preheating system. The preheating device is integrated with the heat box 200. The SOC heat box 200 is provided with a T5 temperature sensor 201 for detecting the temperature inside the heat box. The connection logic diagram of the matching temperature controller TCU is as follows: Figure 4 As shown, TCU is communicated with M.F1, M.F2, T1, T2, and T5 respectively.

[0097] The following uses methane to heat air and preheat the hot box to 750℃ as an example to illustrate how to use the preheating device.

[0098] The air is metered by the M.F1 oxidant metering device 101 and enters the high-efficiency preheating device 100, where it is heated by the electric heater 102. The methane is metered by the M.F2 fuel flow meter 104 and enters the high-efficiency preheating device 100. The air forms turbulence under the action of the spoiler 103, and is fully mixed with the methane under the action of the mixer 106, and then passes through the catalytic burner 108; the air and methane mixture undergoes an oxidation reaction under the action of the catalyst of the catalytic burner 108 and is heated to 800°C; after heating, a high-temperature gas is formed and flows out of the high-efficiency preheating device and enters the SOC hot box 200. The preheating is completed when the temperature value detected by the T5 temperature sensor 201 of the SOC hot box 200 reaches 750°C.

[0099] Based on adaptive control method:

[0100] Figure 4 As shown, TCU is a temperature controller for the high-efficiency preheating device 100; the flow rate of the oxidant metering device M.F1 is represented by Q1, the flow rate of the fuel metering device M.F2 is represented by Q2, and the flow rate of the circulation pipeline 112 is represented by Q3; the system input parameters are: fuel type Fi and the corresponding ignition temperature T obtained by looking up the table Fi , preheating target temperature T T =800℃℃, hot box target temperature T THB =750℃℃, temperature steps are X1, X2, X3, Tx, Q1, Q2, as shown in the following table.

[0101] Table 3

[0102]

[0103]

[0104] (1) The temperature controller TCU system is powered on and self-checked. After the self-check passes, the fuel type Fi and preheating target temperature T are input. T , hot box target temperature T THB ; The system automatically obtains the fuel ignition temperature T according to the calibration parameters Fi , air flow initial value Q1, fuel gas flow initial value Q 2、 The initial value of the circulation pipeline flow is Q3.

[0105] (2) After inputting and obtaining relevant parameters, the system controls the air flow meter M.F1 to open, so as to start operation according to the preset air flow Q1, and the electric heater 102 works.

[0106] (3) The temperature controller TCU detects the temperature T1 of the T1 temperature sensor 107 in real time and adjusts the air flow Q1 according to the temperature T1 until the temperature T1 can rise to T Fi. And / or, adjust the circulation pipeline flow Q3 until T1 can be heated to T Fi .

[0107] (4) When T1>T Fi After that, the fuel flow meter M.F2 starts to work and starts to operate with the Q2 flow rate of fuel gas.

[0108] (5) Real-time detection of T2 temperature, and adjustment of Q2 according to T2 temperature, and / or adjustment of circulation pipeline flow Q3, until T2 ≥ T T .

[0109] (6) Real-time detection of the temperature value T5 of the T5 temperature sensor 201 until T5 ≥ T THB ; If the temperature T5 stabilizes and is lower than the target temperature T THB , then the step length T X Gradually increase the preheating target temperature T T ; T X Subject to revision and adjustment.

[0110] Preferably, the system further comprises step (7) performing over-temperature protection during operation, according to T1-T Fi >X1, perform feedback adjustment of Q1; according to T2-T T >X2, conduct feedback adjustment of Q2; according to T5-T THB >X3, proceed to T T Feedback adjustment. (X1, X2, X3 can be revised and adjusted).

[0111] The schemes of the above embodiments are merely brief descriptions for the purpose of facilitating understanding of the innovative points of the present invention, and should not be understood as limiting the protection scope of the present invention to the above embodiments. All technologies realized based on the contents of the present invention belong to the scope of the present invention.

Claims

1. A SOC system preheating device with a circulation loop, characterized in that: The preheating device comprises a main body and a circulation pipeline; the main body has a hollow cavity, and the hollow cavity has an inlet and an outlet; An electric heater is provided on one side of the hollow cavity close to the inlet, and a catalytic burner is provided on one side of the hollow cavity close to the outlet; The hollow cavity is connected to the oxidant metering device through the inlet. A fuel inlet is provided on the side of the main body, and the fuel inlet is connected to a fuel flow meter; The circulation pipeline is arranged and connected to the side of the main body, and the circulation pipeline and the hollow cavity of the main body form a parallel branch for refluxing the gas discharged from the outlet to the front end of the hollow cavity.

2. The SOC system preheating device with a circulation loop according to claim 1, characterized in that: It also includes a T1 temperature sensor and a T2 temperature sensor. The T1 temperature sensor is arranged in the hollow cavity and before the catalytic burner; the T2 temperature sensor is arranged after the catalytic burner or at the outlet of the hollow cavity.

3. The SOC system preheating device with a circulation loop according to claim 2, characterized in that: The preheating device further includes a controller, which is connected to at least one of the oxidant metering device, the electric heater, the fuel flow meter, the T1 temperature sensor, and the T2 temperature sensor.

4. The SOC system preheating device with a circulation loop according to claim 3, characterized in that: A spoiler is also arranged in the hollow cavity. The spoiler is located behind the electric heater and before the catalytic burner.

5. The SOC system preheating device with a circulation loop according to claim 4, characterized in that: A mixer is also provided in the hollow cavity and is located after the fuel inlet.

6. The SOC system preheating device with a circulation loop according to claim 1, characterized in that: It also includes an ejector reflux device, which is located at the inlet of the hollow cavity and behind the oxidant metering device; the ejector reflux device is connected to the circulation pipeline.

7. The SOC system preheating device with a circulation loop according to claim 6, characterized in that: One end of the circulation pipeline is connected to the ejector reflow device, and the other end is connected to the outlet of the hollow cavity.

8. The SOC system preheating device with a circulation loop according to claim 6, characterized in that: The circulation pipeline is provided with a circulation valve.

9. A preheating system, characterized in that: It comprises the preheating device according to any one of claims 1 to 8, wherein the outlet of the preheating device is connected to a SOC heat box.

10. A preheating system according to claim 9, characterized in that: A T5 temperature sensor is installed inside the SOC hot box.

Images