A pilot plant for a falling bed reactor in a hydrogenation gasification device

Abstract

The utility model relates to a pilot plant of a falling bed reactor in a hydrogasification device, and belongs to the technical field of coal hydrogasification. The device includes a shell, a reactor, a temperature monitoring device and a temperature adjustment device. The reactor is installed inside the shell, and its inner cavity constitutes a reaction zone. The two ends of the reactor extend to the outside of the shell on both sides, constituting the inlet of the reaction medium and the outlet of the reaction product. The reaction medium includes coal powder and hydrogen; the reactor includes at least two sub-reactors connected in sequence, and a heating element is installed on the outside of each sub-reactor; the temperature monitoring device includes a plurality of temperature monitors, and a plurality of temperature monitors are respectively installed on the tube wall of the shell, the sub-reactor and the heating element; the temperature adjustment device is provided with a control cabinet, and the heating element and the plurality of temperature monitors are respectively electrically connected to the control cabinet. The pilot plant does not flash under high pressure and high temperature working conditions, has a small safety risk, a simple debugging method, and a short debugging cycle.

Description

Technical Field

[0001] The present application relates to a pilot plant of a falling bed reactor in a hydrogasification device, belonging to the technical field of coal hydrogasification. Background Art

[0002] As international energy resources become increasingly tight, the coal resource market situation is very grim. The mining and utilization of coal resources are becoming increasingly important. Coupled with the excessive mining of coal resources, high-quality coal has become a scarce commodity, and the market price is also soaring. The remaining low-quality coal that cannot be directly used is piled up like a mountain, which is a serious waste. China has become the world's largest energy consumer, with huge energy market demand and a gradually increasing degree of external dependence. It is particularly important to maintain the stability of the energy security situation. In order to make full and reasonable use of low-quality coal, major domestic research institutes and major universities across the country have joined forces with many strong enterprises to invest intensively in research and development and testing in this area.

[0003] In the prior art, there is a process of directly hydrogenating pulverized coal to produce various fuels and chemical products. Specifically, pulverized coal and hydrogen react under medium temperature (800-1000℃) and high pressure (5-10Ma) conditions to generate methane-rich synthesis gas, high value-added aromatic oil products and high calorific value semi-coke to improve the utilization of low-quality coal. According to the reaction process of hydrogenation, it mainly includes the pretreatment of coal to produce pulverized coal, the hydrogenation reaction of pulverized coal and the separation of the products after the reaction. Among them, the hydrogenation reaction of pulverized coal is the core of the entire reaction process, and different reaction conditions will directly affect the generation of reactants. In order to develop the hydrogenation reaction process, existing enterprises mainly set up pilot plants to test the production and control conditions of products before production, which is used to investigate and verify the operational feasibility of the chemical process, as well as to determine the safety magnification factor and the reliability of the process design, thereby reducing and avoiding the risks that may occur during the process development process.

[0004] The pilot plant of the hydrogasification device in the prior art is mainly a single reaction zone or multiple reaction zones isolated from each other. For example, the patent number is CN214300010U, and the patent name is a hydrogasification furnace. Its essence is that the reactions of each stage of the hydrogenation reaction of pulverized coal and hydrogen in a single reaction zone are carried out in one reaction zone. Since the reaction conditions required for each stage of the hydrogasification reaction of pulverized coal are different, the yield of the target product of the pilot plant of a single reaction zone is relatively low. The gasification device with multiple reaction zones, through theoretical assumptions, sets multiple reaction zones according to the reaction stages of the hydrogasification process, and the reaction zones are separated from each other. After the previous reaction stage is completed, the product enters the next reaction zone to simulate the reaction process of hydrogasification. For example, the patent application number is 202011290010.5, and the patent name is a coal hydrogasification reactor and a method for coal hydrogasification reaction. Its essence is that the reactants enter the next reaction zone for subsequent reactions after the reaction in the previous reaction zone is completed until all reactions are completed. Although this type of gasification device can improve the yield of the target product, the control system of the multi-reaction zone gasification device will increase the supporting equipment due to the control requirements of different reaction parameters and reaction time, making the entire control system complex and costly to manufacture. In addition, since the multi-reaction zone gasification device is an interval reaction, it is difficult to control the reaction time during the actual reaction, resulting in the previous reaction stage not being completed before entering the next reaction stage, resulting in the superposition of reaction stages, resulting in the target product volume cannot be effectively controlled. Therefore, a pilot plant for hydrogenation gasification device is urgently needed to solve the problem that the existing pilot plant has unreasonable reaction zone settings, which makes it difficult to control reaction conditions and leads to low target product. Utility Model Content

[0005] In view of the problems and shortcomings in the prior art, the present application provides a pilot plant of a falling bed reactor in a hydrogenation gasification device to solve the above technical problems.

[0006] To achieve the above-mentioned purpose, the present application provides the following technical solutions: a pilot plant of a falling bed reactor in a hydrogenation gasification device, comprising a shell, a reactor, a temperature monitoring device and a temperature adjustment device, the reactor is installed inside the shell, and its inner cavity constitutes a reaction zone, and the two ends of the reactor extend to the outside of the shell on both sides, constituting an inlet of a reaction medium and an outlet of a reaction product, and the reaction medium comprises coal powder and hydrogen; the reactor comprises at least two sub-reactors connected in sequence, and a heating element is installed on the outside of each sub-reactor; the temperature monitoring device comprises a plurality of temperature monitors, and a plurality of temperature monitors are respectively installed on the tube wall of the shell, the sub-reactor and the heating element; the temperature adjustment device is provided with a control cabinet, and the heating element and the plurality of temperature monitors are respectively electrically connected to the control cabinet.

[0007] Specifically, the shell includes a preheating shell and a reaction shell, and the inner wall of the shell and the outer side of the reactor are filled with thermal insulation cotton; the reactor is installed in the reaction shell, and its two ends extend to the outside of the reaction shell on both sides, forming the reaction medium inlet and the outlet of the reaction product; the interior of the preheating shell is provided with a feed pipe, and the two ends of the feed pipe extend to the outside of the preheating shell, forming the feed inlet and the feed outlet; the preheating shell and the reaction shell are connected to form a vertical reaction vessel through a ferrule, and the feed outlet is connected to the reaction medium inlet. By setting up a preheating shell to preheat the hydrogen, it is convenient for the hydrogen preheated to the reaction temperature to react directly with the pulverized coal, and the hydrogen will not consume the heating heat of the heating element, and the heating heat is all provided for the energy of the pulverized coal bond breaking, which can improve the yield of the reaction product in the first reaction stage.

[0008] Specifically, the feed inlet of the preheating shell is connected to an external hydrogen gas source pipeline, and a pulverized coal pipeline is connected to the pipeline between the feed outlet and the reaction medium inlet. One end of the pulverized coal pipeline extends to the outside of the reaction shell to form a pulverized coal inlet, and the pulverized coal inlet is also connected to a conveying gas pipeline, and the end of the conveying gas pipeline is connected to a nitrogen gas source, and a pressure reducing valve, a safety valve, a first valve, a flow meter and a regulating valve are sequentially connected to the pipeline between the nitrogen gas source and the pulverized coal inlet, the outlet of the safety valve is connected to a venting pipeline, and the venting pipeline is connected to a third valve; the outer surface of the feed pipeline is sheathed with a metal tubular electric heating element to form a preheating electric heater.

[0009] Furthermore, the outlet of the post-reaction product at the bottom of the reaction shell is connected to an exhaust pipeline, the pipeline of the exhaust pipeline near the reaction shell side is bent to form a bent portion, and a pressure gauge, a second valve and a back pressure valve are connected to the exhaust pipeline away from the reaction shell side, and the outlet of the back pressure valve is connected to a discharge port; a cooling device is connected to the outside of the bent portion of the exhaust pipeline to form a cooling section, and the elbow length of the cooling section is ≥2.5m. This application uses nitrogen as the conveying gas for pulverized coal, and a pressure reducing valve, a safety valve, a first valve, a flow meter and a regulating valve are arranged on the conveying gas pipeline, and a pressure gauge, a second valve and a back pressure valve are arranged on the exhaust pipeline at the bottom of the reaction shell to achieve pressure and flow control of the reaction gas.

[0010] Specifically, temperature monitors are installed at positions corresponding to the preheating electric heater and the material delivery outlet on the preheating shell, respectively, for detecting the temperature of the preheating electric heater and the material delivery outlet; temperature monitors are installed at the upper, middle and lower positions of the outer shell of the preheating shell and the reaction shell, respectively, for detecting the temperature of the shell tube wall. By arranging temperature monitors at different positions on the outer shell of the preheating shell and the reaction shell, it is possible to control the heating element to stably heat the reaction zone by detecting the temperature of the temperature monitor on the outer side of the shell during the reaction process when the reaction zone is heated and heated, so as to ensure the stable rise of the temperature of the reaction zone, and also ensure that the heating and heating of each part of the reaction zone is uniform to avoid local overheating.

[0011] Specifically, the sub-reactor is a vertical pressure pipe, and the number of sub-reactors is three; the three vertical pressure pipes are connected in sequence to form a first-stage reactor, a second-stage reactor and a third-stage reactor, and the length ratio of the first-stage reactor, the second-stage reactor and the third-stage reactor is 2:1:1; the positions corresponding to the outlets of each sub-reactor on the reaction shell are respectively installed with temperature monitors for detecting the temperature of the outlets of the sub-reactors; the inlet of the first-stage reactor constitutes the inlet of the reaction medium, and the outlet of the three-stage reactor extends radially toward the bottom of the reaction shell to the outside, constituting the outlet of the reaction product. According to the different reaction stages of the pulverized coal hydrogasification reaction, the present application sets three interconnected sub-reactors to form three continuous reaction zones, and according to the characteristic that the reaction time of the first stage is longer than the reaction time of the subsequent reaction stage, the length of the first-stage reactor is set to be longer than the length of the subsequent second-stage and third-stage reactors, so as to improve the degree of the first-stage reaction, thereby ensuring that the subsequent reaction is sufficient and improving the generation of effective components in the reactants.

[0012] Specifically, a metal tubular electric heating element is sleeved on the outer side of the sub-reactor, and a temperature monitor is installed at a position corresponding to the electric heating element of the sub-reactor on the reaction shell, which is used to detect the temperature of the heating element; a quenching medium interface is installed at a position near the outlet of the sub-reactor on the reaction shell; one end of the quenching medium interface extends into the cavity of the sub-reactor in the direction of the sub-reactor, and the other end is connected to an external gas source, and the quenching medium interface at the outlet of the three-stage reactor is connected to the pipeline on the outlet side of the first valve on the gas pipeline through a quenching pipeline, and a fourth valve is provided on the quenching pipeline. By setting up the quenching medium interface, in order to avoid overheating of the bottom of the sub-reactor and the exhaust pipeline, the temperature of the pilot device and the exhaust pipeline is controlled by introducing the quenching medium for quenching and cooling.

[0013] Specifically, the temperature monitor is a K-scale temperature sensor, which is a detachable mounting structure. The test end of the temperature monitor on the sub-reactor is connected to the side wall of the sub-reactor through a heat collecting block, and is used to measure the side wall temperature of the sub-reactor.

[0014] Specifically, an on-site control unit is provided in the control cabinet, and the on-site control unit includes a controllable power regulator, an ultra-high temperature alarm unit, an outlet temperature display and adjustment unit and a PLC module. The heating element, the temperature monitor and the PLC operation module are electrically connected to the thyristor power regulator respectively, and the PLC module is also electrically connected to the user's DCS control system; the ultra-high temperature alarm unit is electrically connected to the temperature monitor installed on the heating element, and is used to alarm when the heating element exceeds the set temperature and cut off the heating element; the outlet temperature display and adjustment unit is respectively connected to the temperature monitor and the heating element of the sub-reactor, and is used to adjust the power output of the heating element according to the temperature of the sub-reactor.

[0015] Furthermore, the control cabinet is also provided with a remote control signal interface, and the control signal interface includes an interface for controlling the start and stop of the heating element and an interface for indicating the working state, and the signal of the receiving contact of the interface for indicating the working state of the heating element is connected to the display unit of the user's DOS control system. The present application sets an on-site control unit to enable the power regulator to adjust the power output ratio of the electric heater according to the outlet temperature of the sub-reactor, and directly transmits and feeds back the signal to the user's DCS central control system through integrated calculation of the PLC module to realize on-site control operation. At the same time, a remote control signal interface is set on the control cabinet for connecting with the user's DOS central control system to achieve the purpose of remote control. Through the control signal interface, the temperature measurement and control signals are directly fed back to the user's DCS central control system, thereby realizing remote control through the user's DOS central control system without the need to set up a local control system separately, thereby realizing both on-site and remote control modes.

[0016] Compared with the prior art, the beneficial effects of this application are:

[0017] 1. The present application sets up a pilot plant of a coal hydrogasification reactor which is connected in series by at least two sub-reactors to form a continuous reaction zone, so as to simulate the reaction process of each reaction stage of pulverized coal hydrogasification, and then heats the sub-reactor by setting an electric heating element on the outside of the sub-reactor according to the reaction conditions of pulverized coal hydrogasification, so as to control the reaction temperature of different reaction stages. The pilot plant of the present application allows pulverized coal to enter the reactor from the inlet along with hydrogen via nitrogen as a transport gas, and then sequentially passes through each sub-reactor to perform the hydrogasification reaction of pulverized coal. The pulverized coal is cracked and the secondary reactant is hydrogenated under high temperature and high pressure. Each reaction stage is connected in sequence, and the product of the previous reaction stage is used as the reactant of the subsequent reaction stage, so that the reactants of different stages will not mix with each other, thereby improving the yield of the target product.

[0018] 2. On the basis of the above, in order to increase the reaction depth of each reaction stage and thus increase the yield of subsequent reactants, the present application controls the reaction temperature of the sub-reactor by setting a temperature monitoring device and a temperature adjustment device, and sets regulating devices on the pulverized coal, hydrogen inlet and exhaust pipelines to control the reaction amount of the reactants including pulverized coal and hydrogen, thereby achieving better control over the reaction depth.

[0019] 3. On the basis of the above, the control cabinet of the present application is equipped with a local control unit and a remote control signal interface. The control cabinet is equipped with a power regulator, which can adjust the power output ratio of the electric heater according to the outlet temperature of the medium. Through the integrated operation of the PLC module, the signal is directly fed back to the user's DCS central control system for local control. Through the control signal interface, the temperature measurement and control signals are directly fed back to the user's DCS central control system, thereby realizing remote control through the user's DOS central control system without the need to set up a local control system separately, realizing both local and remote control modes. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 Schematic diagram of the structure of the pilot plant of the falling bed reactor in the hydrogasification device of this embodiment (1);

[0021] Figure 2 Schematic diagram of the structure of the pilot plant of the falling bed reactor in the hydrogasification device of this embodiment (2);

[0022] Figure 3 This is a schematic diagram of the structure of the pilot plant of the falling reactor in the hydrogasification device of this embodiment connected to the gas transmission pipeline and the exhaust pipeline;

[0023] Figure 4 This is a schematic diagram of the control cabinet structure of the pilot plant of the drop reactor in the hydrogasification device of this embodiment;

[0024] Figure 5 The electrical schematic diagram (1) of the operation of the electric heating element of the pilot plant of the drop reactor in the hydrogasification device of this embodiment;

[0025] Figure 6 This is the electrical schematic diagram (2) of the operation of the electric heating element of the pilot plant of the falling reactor in the hydrogasification device of this embodiment. DETAILED DESCRIPTION

[0026] See also Figure 1-Figure 6This embodiment discloses a pilot plant of a falling bed reactor in a hydrogenation gasification device, including a shell, a reactor, a temperature monitoring device and a temperature adjustment device, which includes a preheating shell 3 and a reaction shell 1, the working pressure of the preheating shell is 7.1Mpa, the design pressure is 8.0Mpa, the reaction shell is an explosion-proof high temperature resistant shell, the shell working pressure is 7.0-7.1Mpa, and the shell is designed to withstand a high temperature of 1400 degrees Celsius. Insulation cotton is filled between the inner wall of the shell and the outside of the reactor; the reactor is installed in the reaction shell, its inner cavity constitutes a reaction zone, and its two ends extend to the outside of the reaction shell on both sides, constituting the reaction medium inlet and the outlet of the reaction product; the interior of the preheating shell is provided with a feed pipe, and the two ends of the feed pipe extend to the outside of the preheating shell, constituting the feed inlet and the feed outlet; the preheating shell 3 and the reaction shell 1 are fixedly connected to form a sealed vertical reaction vessel through an octagonal pad 2 and a full-thread high-strength stud 5 and a nut 4, and the feed outlet is connected to the reaction medium inlet. The reaction medium includes coal powder and hydrogen; the reactor includes three sub-reactors connected in sequence, and a heating element is installed on the outside of each sub-reactor; the temperature monitoring device includes a plurality of temperature monitors. The temperature adjustment device of this embodiment is provided with a control cabinet, and the heating element and the plurality of temperature monitors are electrically connected to the control cabinet respectively.

[0027] The feed inlet N1 of the preheating shell of this embodiment is connected to an external hydrogen gas source pipeline, and the hydrogen inlet temperature is designed to be 20°C. A pulverized coal pipeline is connected to the pipeline between the feed outlet and the reaction medium inlet, and one end of the pulverized coal pipeline extends to the outside of the reaction shell to form a pulverized coal inlet N3, and the pulverized coal inlet is also connected to a conveying gas pipeline, and the end of the conveying gas pipeline is connected to a nitrogen gas source, and a pressure reducing valve, a safety valve, a first valve, a flow meter and a regulating valve are sequentially connected to the pipeline between the nitrogen gas source and the pulverized coal inlet, and the outlet of the safety valve is connected to a venting pipeline, and the venting pipeline is connected to a third valve; the pulverized coal inlet temperature is designed to be 25°C, and the pulverized coal flow rate is 1 kg / h; a metal tubular electric heating element is sheathed on the outer surface of the feed pipeline to form a preheating electric heater;

[0028] The outlet of the post-reaction product at the bottom of the reaction shell is connected to the exhaust pipeline N2, the exhaust pipeline near the reaction shell side is in a bent structure, forming a bent portion, and the exhaust pipeline away from the reaction shell side is connected to a pressure gauge, a second valve and a back pressure valve, and the outlet of the back pressure valve is connected to a discharge port; the outer side of the bent portion of the exhaust pipeline is connected to a cooling device to form a cooling section, and the bend length of the cooling section is ≥2.5m.

[0029] In addition, temperature monitors are installed at positions corresponding to the preheating electric heater and the material delivery outlet on the preheating shell of this embodiment, respectively, for detecting the temperature of the preheating electric heater and the material delivery outlet; the heating temperature of the preheating electric heater of this embodiment is ≥950°C, the maximum temperature is designed to be 1150°C, and the material delivery outlet is designed to be 900°C, which is subject to the value measured by the temperature monitor; temperature monitors are installed at the upper, middle and lower positions of the outer shells of the preheating shell and the reaction shell, respectively, for detecting the temperature of the shell tube wall, see Figure 1 The temperature of the preheating shell tube wall in this embodiment is designed to be 300°C at the maximum temperature of the external tube wall of the material delivery outlet, and the temperature value monitored by the temperature monitor is ≤200°C.

[0030] Further, the three vertical pressure pipes formed by the three sub-reactors of this embodiment are connected in sequence to form a first-stage reactor, a second-stage reactor and a third-stage reactor, and the length ratio of the first-stage reactor, the second-stage reactor and the third-stage reactor is 2:1:1. The positions corresponding to the outlets of each sub-reactor on the reaction shell are respectively installed with temperature monitors for detecting the temperature of the outlets of the sub-reactors. The inlet of the first-stage reactor constitutes the inlet of the reaction medium, and the outlet of the three-stage reactor extends radially toward the bottom of the reaction shell to the outside, constituting the outlet of the reaction product. The outer side of the sub-reactor of this embodiment is sheathed with a metal tubular electric heating element, and the positions corresponding to the electric heating elements of the sub-reactors on the reaction shell are respectively installed with temperature monitors for detecting the temperature of the heating elements; the heating temperature of the electric heating elements of the sub-reactors of this embodiment is ≥950°C, the maximum design temperature is 1150°C, and the sub-reactor outlet temperature setting value is 900°C. A quenching medium interface N4-N6 is disassembled and installed at a position near the outlet of the sub-reactor on the reaction shell; one end of the quenching medium interface extends toward the sub-reactor into the cavity of the sub-reactor, and the other end is connected to an external gas source, and the quenching medium interface at the outlet of the three-stage reactor is connected to the pipeline on the outlet side of the first valve on the gas pipeline through a quenching pipeline, and a fourth valve is provided on the quenching pipeline.

[0031] The temperature monitor of this embodiment is a K-scale temperature sensor, which is a detachable installation structure. The test end of the temperature monitor on the sub-reactor is connected to the side wall of the sub-reactor through the heat collecting block, and is used to measure the side wall temperature of the sub-reactor.

[0032] Furthermore, the power supply of the control cabinet of this embodiment is registered as 380V, three-phase five-wire, and the control cabinet is provided with 380V and 220V power indicator lights WL1-WL2, local control preheating electric heater and sub-reactor electric heating working indicator lights GL1-GL4, remote control preheating electric heater and sub-reactor electric heating working indicator lights RL1-RL4, and local remote control switching switch S5. The connection circuits of the preheating electric heater and the reactor electric heater of this embodiment are respectively provided with controllable power regulators SCR1-SCR4 and dry-type transformers R1-R2, wherein circuit breakers QF3-QF10 are respectively connected between the power line and the electronic regulator and between the dry-type transformer and the electric heater. In order to improve the circuit safety of the electric heater, AC contactors KM1-KM4 are respectively connected to the preheating circuit and the reactor electric heating circuit. The ultra-high temperature alarm unit, outlet temperature display and adjustment unit (digital controller TIC1-TIC4) and PLC module, the heating element, the temperature monitor and the PLC operation module are electrically connected to the thyristor power regulator respectively, and the PLC module is also electrically connected to the user's DCS control system; the ultra-high temperature alarm unit is electrically connected to the temperature monitor installed on the heating element, which is used to alarm when the heating element exceeds the set temperature and cut off the heating element; the outlet temperature display and adjustment unit is respectively connected to the temperature monitor and the heating element of the sub-reactor, which is used to adjust the power output of the heating element according to the temperature of the sub-reactor; the temperature adjustment device of this embodiment is provided with an on-site control unit to realize that the power regulator adjusts the power output ratio of the electric heater according to the outlet temperature of the sub-reactor, and the signal is directly fed back to the user's DCS central control system through the integrated operation of the PLC module to realize on-site control operation. At the same time, a remote control signal interface is provided on the control cabinet to connect with the user's DOS central control system to achieve the purpose of remote control.

[0033] Since there is hydrogen in the coal pulverization hydrogenation reaction, and the reaction conditions require heating and pressurization, the safety requirements for the pilot plant are relatively high. Therefore, when designing the pilot plant of this embodiment, the explosion-proof level is designed to be ExdIICT4 and the protection level is IP65. At the same time, before use, debugging work is required to verify the safety of the pilot plant. The specific adjustments include the following steps:

[0034] S1. First, adjust the pressure of the equipment; after the pilot plant has passed the airtight acceptance, adjust the equipment pressure to 7Mpa by adjusting the back pressure valve on the exhaust pipeline of the pilot plant;

[0035] S2. After completing the equipment pressure adjustment of S1, introduce gas and control the gas introduction flow rate; first open the nitrogen source, and introduce nitrogen from the reaction medium inlet at the top of the reactor after being reduced in pressure by the pressure reducing valve, and vent from the exhaust pipe at the bottom of the reactor; in this process, manually adjust the regulating valve to control the nitrogen flow rate to be stable at 5Nm3 / h, and the back pressure valve on the exhaust pipe controls the reactor pressure to be stable at 7Mpa;

[0036] S3. After the gas flow and pressure adjustment in S2 are completed, the reactor is heated and heated; this process includes heating the preheating zone where the preheating shell is located and the reaction zone where the reaction shell is located, and the heating rate is 1.5°C / min until the outlet gas temperature of the preheating zone reaches 800-1000°C, and the outlet temperature of each sub-reactor reaches the set temperature, the set temperature range is 800-1000°C, and the outlet set temperature of each sub-reactor is the same, and the temperature of the heating element of the preheating zone and the reactor does not exceed 1100°C;

[0037] S4. After completing the heating and temperature raising of S3, the reaction zone is calibrated in the constant temperature section; the temperature of the upper, middle and lower parts of the reaction zone is measured by using a calibrated thermocouple. When the temperature of each section of the calibrated thermocouple reaches the set temperature and can be stable for 30 minutes, and the temperature can fluctuate within ±2°C; when the temperature of each section of the heating element does not exceed 1100°C, the calibrated thermocouple is extended from the reaction medium outlet at the bottom of the reactor into the reactor, and the thermocouple is extended to the reaction medium inlet position as the initial point of temperature measurement, and then the calibrated thermocouple is moved down one by one, and the temperature is measured to start the constant temperature section calibration; the subsequent temperature measurement points are moved down by 50mm in turn, and the temperature measurement end point is the bottom outlet of the reactor; a displacement scale is marked on the outside of the reaction shell to record the length of the thermocouple withdrawal, and the test readings of each temperature measurement point need to keep the temperature unchanged for a certain period of time before it can be used as temperature measurement data;

[0038] S5. Determine the constant temperature zone; when the temperature of the calibrated thermocouple rises by no more than 10°C for two consecutive places, it enters the constant temperature zone; the thermocouple continues to extend downward by 50mm, and when the temperature drops by more than 10°C for two consecutive places, the constant temperature zone determination ends;

[0039] S6. Dehumidify the pilot plant; after the constant temperature zone of S5 is calibrated, continue to introduce nitrogen and keep the set temperature constant for more than 8 hours, ensuring that the heating and constant temperature time is ≥24 hours to remove moisture from the insulation cotton;

[0040] S7. Evaluate the debugging effect; if the outlet temperature of each reaction section reaches the set value and can be maintained for 1 hour, and the maximum temperature of the outer wall of the pilot plant during the debugging process is ≤120°C, the wall temperature is considered qualified and the debugging has achieved the expected effect;

[0041] S8. Cool down and reduce the pressure of the equipment. After completing the high-pressure commissioning, turn off the heating elements of each section and cut off the power supply of the control cabinet. Close the first nitrogen valve and the nitrogen gas source. Allow the equipment to cool down naturally. Open the third valve of the exhaust pipe and slowly reduce the pressure of the equipment to normal pressure to complete the commissioning work.

[0042] Working principle: When the pilot plant of the falling bed reactor in the hydrogasification device of this embodiment is working, the pulverized coal enters the first-stage reactor along with the transported nitrogen, and the hydrogen enters the first-stage reactor together after being preheated. In the first-stage reactor, the pulverized coal is first heated to undergo a pyrolysis reaction. The volatile free radicals and molecular fragments generated by the thermal decomposition of the pulverized coal in the hydrogen-rich atmosphere are combined with hydrogen and stabilized, making it easier to escape from the inside of the particles, and the yield of the generated gas and tar is increased, especially the yield of CH4. After that, the material at the outlet of the first-stage reactor enters the second-stage reactor and the third-stage reactor for hydrogenation gasification reaction. The reaction of hydrogen and active carbon in the semi-coke in the gasification stage obtains CH4-rich gas, as well as high-value-added liquid organic products such as BTX (benzene, toluene, xylene) and PCX (phenol, cresol, xylenol). In this process, the temperature adjustment device of this embodiment adopts a fully adjustable control method to increase the adjustment amount of the medium temperature adjustment. This control can extend the service life of the electrical components. After the electric heater is working, the control part can flexibly change the operating temperature to achieve the best heating operation, so that the output temperature of the electric heater is uniform and the temperature rise is stable. The temperature tracking accuracy is high, the response is fast, the thermal efficiency is high, and energy is saved. The electric heater is set with overheat protection, which can effectively avoid the phenomenon of over-temperature dry burning and extend the service life of the electric heater. The temperature adjustment device can adjust the outlet temperature according to the control signal and can work stably for a long time.

[0043] The implementation methods of the present application are described in detail above in conjunction with the embodiments, but the present application is not limited to the above-mentioned implementation methods. For ordinary technicians in this technical field, after knowing the contents recorded in the present application, they can make several equivalent changes and substitutions thereto without departing from the principles of the present application, and these equivalent changes and substitutions should also be regarded as belonging to the protection scope of the present application.

Claims

1. A pilot plant of a falling bed reactor in a hydrogasification device, comprising a shell, a reactor, a temperature monitoring device and a temperature adjusting device, characterized in that: The reactor is installed inside the shell, and its inner cavity constitutes a reaction zone, and the two ends of the reactor extend to the outside of the shell on both sides, constituting the inlet of the reaction medium and the outlet of the reaction product, and the reaction medium includes coal powder and hydrogen; the reactor includes at least two sub-reactors connected in sequence, and a heating element is installed on the outside of each sub-reactor; the temperature monitoring device includes a plurality of temperature monitors, and the plurality of temperature monitors are respectively installed on the tube wall of the shell, the sub-reactor and the heating element; the temperature adjustment device is provided with a control cabinet, and the heating element and the plurality of temperature monitors are respectively electrically connected to the control cabinet.

2. The pilot plant of a falling bed reactor in a hydrogasification device according to claim 1, characterized in that: The shell comprises a preheating shell and a reaction shell, and the space between the inner wall of the shell and the outer side of the reactor is filled with heat-insulating cotton; the reactor is installed in the reaction shell, and its two ends extend to the outer side of the reaction shell on both sides, forming a reaction medium inlet and a reaction product outlet; a feed pipe is arranged inside the preheating shell, and the two ends of the feed pipe extend to the outer side of the preheating shell, forming a feed inlet and a feed outlet; the preheating shell and the reaction shell are connected to form a vertical reaction vessel through a ferrule, and the feed outlet is connected to the reaction medium inlet.

3. The pilot plant of a falling bed reactor in a hydrogasification device according to claim 2, characterized in that: The feed inlet of the preheating shell is connected to an external hydrogen gas source pipeline, and a pulverized coal pipeline is connected to the pipeline between the feed outlet and the reaction medium inlet. One end of the pulverized coal pipeline extends to the outside of the reaction shell to form a pulverized coal inlet, and the pulverized coal inlet is also connected to a conveying gas pipeline, and the end of the conveying gas pipeline is connected to a nitrogen gas source, and a pressure reducing valve, a safety valve, a first valve, a flow meter and a regulating valve are sequentially connected to the pipeline between the nitrogen gas source and the pulverized coal inlet, the outlet of the safety valve is connected to a venting pipeline, and the venting pipeline is connected to a third valve; the outer surface of the feed pipeline is sheathed with a metal tubular electric heating element to form a preheating electric heater.

4. The pilot plant of a falling bed reactor in a hydrogasification device according to claim 3, characterized in that: The outlet of the post-reaction product at the bottom of the reaction shell is connected to an exhaust pipeline, the pipeline of the exhaust pipeline close to the reaction shell side is in a bent structure, forming a bent portion, and the exhaust pipeline away from the reaction shell side is connected to a pressure gauge, a second valve and a back pressure valve, and the outlet of the back pressure valve is connected to a discharge port; the outer side of the bent portion of the exhaust pipeline is connected to a cooling device to form a cooling section, and the bend length of the cooling section is ≥2.5m.

5. The pilot plant of a falling bed reactor in a hydrogasification device according to claim 3, characterized in that: Temperature monitors are installed at positions corresponding to the preheating electric heater and the material delivery outlet on the preheating shell, respectively, for detecting the temperatures of the preheating electric heater and the material delivery outlet; temperature monitors are installed at the upper, middle and lower positions of the outer shells of the preheating shell and the reaction shell, respectively, for detecting the temperature of the shell tube wall.

6. The pilot plant of a falling bed reactor in a hydrogasification device according to claim 2, characterized in that: The sub-reactor is a vertical pressure pipeline, and the number of sub-reactors is three; the three vertical pressure pipelines are connected in sequence to form a first-stage reactor, a second-stage reactor and a third-stage reactor, and the length ratio of the first-stage reactor, the second-stage reactor and the third-stage reactor is 2:1:1; a temperature monitor is respectively installed at a position corresponding to the outlet of each sub-reactor on the reaction shell, for detecting the temperature of the outlet of the sub-reactor; the inlet of the first-stage reactor constitutes the inlet of the reaction medium, and the outlet of the three-stage reactor extends radially toward the bottom of the reaction shell to the outside, constituting the outlet of the reaction product.

7. The pilot plant of a falling bed reactor in a hydrogasification device according to claim 6, characterized in that: The outer side of the sub-reactor is sheathed with a metal tubular electric heating element, and temperature monitors are installed at positions corresponding to the electric heating elements of the sub-reactor on the reaction shell to detect the temperature of the heating elements; a quenching medium interface is decomposed and installed at a position on the reaction shell adjacent to the outlet of the sub-reactor; one end of the quenching medium interface extends into the cavity of the sub-reactor toward the sub-reactor, and the other end is connected to an external gas source, and the quenching medium interface at the outlet of the three-stage reactor is connected to the pipeline on the outlet side of the first valve on the gas pipeline through a quenching pipeline, and a fourth valve is provided on the quenching pipeline.

8. The pilot plant of a falling bed reactor in a hydrogasification device according to claim 1, characterized in that: The temperature monitor is a K-scale temperature sensor, which is a detachable mounting structure. The test end of the temperature monitor on the sub-reactor is connected to the side wall of the sub-reactor through a heat collecting block, and is used to measure the side wall temperature of the sub-reactor.

9. The pilot plant of a falling bed reactor in a hydrogasification device according to claim 1, characterized in that: An on-site control unit is provided in the control cabinet, and the on-site control unit includes a controllable power regulator, an ultra-high temperature alarm unit, an outlet temperature display and adjustment unit and a PLC module. The heating element, the temperature monitor and the PLC operation module are electrically connected to the thyristor power regulator respectively, and the PLC module is also electrically connected to the user's DCS control system; the ultra-high temperature alarm unit is electrically connected to the temperature monitor installed on the heating element, and is used to alarm when the heating element exceeds the set temperature and cut off the heating element; the outlet temperature display and adjustment unit is respectively connected to the temperature monitor and the heating element of the sub-reactor, and is used to adjust the power output of the heating element according to the temperature of the sub-reactor.

10. The pilot plant of a falling bed reactor in a hydrogasification device according to claim 9, characterized in that: The control cabinet is also provided with a remote control signal interface, which includes a heating element start and stop interface and a working status indication interface, and the signal of the receiving contact of the heating element working status indication interface is connected to the display unit of the user's DOS control system.

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