An experimental system and method for gasification of newly formed semicoke by coal combustion and mixed pyrolysis

Abstract

An experimental system and method for gasifying newly formed semi-coke by coal combustion hybrid pyrolysis. The carrier supply device provides a stable pyrolysis atmosphere in the pyrolysis furnace to ensure the stability of the pyrolysis process. The temperature control heating equipment is connected with a thermocouple and a TG thermal gravimetric analyzer. The thermocouple collects the temperature in the pyrolysis furnace in real time and can transmit it back to the temperature control heating equipment. The temperature control heating equipment compares the collected temperature with the temperature obtained through experiments by the TG thermal gravimetric analyzer, and then adjusts the temperature in the pyrolysis process of the pyrolysis furnace to meet the temperature requirements in each stage of the pyrolysis process. The pyrolysis furnace is connected to a volatile fraction collection cylinder and an analysis unit, which can store and analyze the volatile substances generated by pyrolysis to obtain the gasification situation of the newly formed semi-coke. The pyrolysis process is divided into four stages, and the volatile fractions in the gasification process of the newly formed semi-coke can be collected completely and accurately.

Description

Technical Field

[0001] The present invention relates to the technical field of clean thermal utilization of coal, and specifically provides an experimental system and method for gasifying newly formed semicoke by coal combustion hybrid pyrolysis. Background Art

[0002] As an important industrial production fuel, coal is the main raw material for thermal power generation. With the increasing difficulty of coal mining, the quality of coal has gradually declined. When burning some low-quality coal, not only is the combustion incomplete, but black smoke also appears during the boiler combustion process, ultimately leading to boiler ash deposition and carbonization, affecting the combustion efficiency and shortening the boiler life. With the application of clean coal technology, cascade utilization of energy can effectively improve the comprehensive utilization rate of coal resources.

[0003] The main reactions of the hierarchical utilization of coal are pyrolysis gasification and coke combustion. Among them, coal pyrolysis is the process in which the organic structure in coal breaks and decomposes to release volatile matter at a relatively high temperature. The products after the coal pyrolysis reaction are mainly semicoke, as well as some tar and gas. The pyrolysis gas mainly includes H2, CO, CO2, and high-calorific value light hydrocarbon gases, etc. The semicoke can further react with H2O and CO2 under certain conditions to form coal gas, realizing the deep gasification of coal.

[0004] In the gasification process of the residual coke during pyrolysis, usually the residual coke is first cooled and then gasified starting from room temperature. Generally, as the temperature rises, the non-carbon atoms in the sample gradually break and decompose, and the organic matter continues to break and decompose to release volatile matter during the gasification process, and the remaining structure is arranged more orderly, making the gasification reaction more difficult. The main reactions of coke gasification are:

[0005] C + O2 = CO2

[0006] C + 1 / 2O2 = CO

[0007] C + H2O = CO + H2

[0008] C + CO2 = 2CO

[0009] However, the problem is that the coal combustion hybrid pyrolysis or coupled pyrolysis technology changes the gasification characteristics of the newly formed semicoke during the pyrolysis process. Using traditional coke gasification obviously cannot meet the requirements, and does not consider the influence of factors such as the change of fuel type, the different mixed pyrolysis temperatures, and the volatile matter released during the mixed pyrolysis process on the coke gasification reaction process. Summary of the Invention

[0010] Aiming at the problem of incomplete coal combustion caused by the influence on the volatile coke gasification reaction process during the coal combustion hybrid pyrolysis in the prior art, the present invention provides an experimental system and method for gasifying newly formed semicoke by coal combustion hybrid pyrolysis.

[0011] The present invention is realized through the following technical solutions:

[0012] An experimental system for coal combustion hybrid pyrolysis to produce nascent semi-coke gasification, characterized in that it includes a pyrolysis furnace, a feed pretreatment device and a carrier supply device;

[0013] The side wall of the pyrolysis furnace is connected with a feed pretreatment device, a carrier supply device and a temperature control heating device;

[0014] The gas outlet at the top of the pyrolysis furnace is successively connected to a volatile fraction collection bottle and an analysis unit;

[0015] The input end of the temperature control heating device is respectively connected to the cold end of a thermocouple and the signal output end of a TG thermal decomposition thermogravimetric analyzer, and the hot end of the thermocouple is connected to the pyrolysis furnace;

[0016] A partition is arranged inside the pyrolysis furnace for carrying a mixed sample; the connection ends of the feed pretreatment device, the carrier supply device and the thermocouple with the pyrolysis furnace are respectively arranged corresponding to the positions for carrying the mixed sample.

[0017] Further, the feed pretreatment device includes a feed valve, a mixing device, a grinding and sieving device and a weighing and metering device connected in sequence, and the discharge port of the weighing and metering device is connected to the pyrolysis furnace.

[0018] Further, the carrier supply device includes a nitrogen gas cylinder and a carbon dioxide gas cylinder;

[0019] The nitrogen gas cylinder and the carbon dioxide gas cylinder are respectively connected to two input ends of a three-way inlet valve, and the output end of the three-way inlet valve is connected to the pyrolysis furnace.

[0020] Further, a thermometer is arranged at the top of the pyrolysis furnace for detecting the temperature of the volatile gas.

[0021] An experimental method for coal combustion hybrid pyrolysis to produce nascent semi-coke gasification, characterized in that it includes the following steps:

[0022] Step 1, under a nitrogen atmosphere, gradually heat the mixed sample to the final temperature of the first stage. During the heating process, unstable volatile gas is released, and a degassed mixed sample is generated to complete the first-stage pyrolysis process;

[0023] Step 2, under a nitrogen atmosphere, maintain the final temperature of the first stage, keep the degassed mixed sample at a constant temperature for a first set duration, pyrolyze the long-chain organic matter in the degassed mixed sample, and continuously release a part of the volatile matter to produce nascent semi-coke to complete the second-stage pyrolysis process;

[0024] Step 3: Under a carbon dioxide atmosphere, starting from the final temperature of the first stage, gradually heat the newly formed semicoke through CO2 gasification until the final temperature of the third stage. The long-chain organic compounds in the newly formed semicoke continue to pyrolyze, and the remaining volatile components are released to form molten newly formed semicoke, completing the pyrolysis process of the third stage;

[0025] Step 4: Under a carbon dioxide atmosphere, maintain the final temperature of the third stage for a second set time period for heat preservation. The molten newly formed semicoke forms coke, completing the pyrolysis process of the fourth stage;

[0026] Step 5: Collect and analyze the volatile gas generated in Steps 1 to 4.

[0027] Furthermore, the final temperatures of the first stage and the third stage are obtained through pyrolysis experiments using a TG thermal gravimetric analyzer.

[0028] Furthermore, the final temperature of the first stage does not exceed 600 °C, and the final temperature of the third stage does not exceed 900 °C.

[0029] Furthermore, the range of the final temperature of the first stage is 200 - 300 °C.

[0030] Furthermore, the first set time period is not less than 20 min, and the second set time period is not less than 30 min.

[0031] Furthermore, the heating rate in Steps 1 and 3 is 20 - 40 °C / min.

[0032] Compared with the prior art, the present invention has the following beneficial technical effects:

[0033] An experimental system for coal combustion hybrid pyrolysis to produce newly formed semicoke gasification according to the present invention includes a pyrolysis furnace carrier supply device and a temperature control heating device. The carrier supply device can provide a stable pyrolysis atmosphere in the pyrolysis furnace to ensure the stability of the pyrolysis process. The temperature control heating device is connected with a thermocouple and a TG thermal gravimetric analyzer. The thermocouple can collect the temperature in the pyrolysis furnace in real time and transmit it back to the temperature control heating device. The temperature control heating device can compare the collected temperature with the temperature obtained through experiments by the TG thermal gravimetric analyzer, and then adjust the temperature in the pyrolysis process of the pyrolysis furnace to meet the temperature requirements of each stage in the pyrolysis process; The pyrolysis furnace is connected with a volatile gas collection bottle and an analysis unit, which can store and analyze the volatile substances generated by pyrolysis to obtain the situation of newly formed semicoke gasification.

[0034] Furthermore, the pyrolysis furnace is also connected with a feed pretreatment device, which can preprocess samples with different ratios, can simulate the situation of different coals, conduct analysis and treatment under various conditions, obtain a mixed sample and supply it to the pyrolysis furnace.

[0035] Further, the pyrolysis furnace is connected to a carrier supply device, which replaces and supplies different carrier environments required during the pyrolysis process to improve the accuracy of data analysis.

[0036] An experimental method for coal combustion hybrid pyrolysis to produce nascent semicoke gasification in the present invention involves heating a mixed raw material to release unstable volatile components, discharging the unstable volatile components, and then maintaining the final temperature of the first stage to pyrolyze long-chain organic substances, gradually discharging the volatile components to generate nascent semicoke. Subsequently, it is heated step by step again to continue pyrolyzing long-chain organic substances, and most of the volatile components are released. Finally, the final temperature of the second stage is maintained to completely release the volatile gas and generate coke. The generated volatile gas is collected and analyzed to obtain the pyrolysis situation of the nascent semicoke. The present invention analyzes the gasification characteristics of the nascent semicoke produced by hybrid pyrolysis. Different from traditional coke that is cooled to room temperature and then gasified, the nascent semicoke needs to consider the part of the volatile components released during the pyrolysis process, and the pyrolysis temperature is directly raised to the gasification temperature after pyrolysis. Through the mixed combustion of coal, to a certain extent, it realizes the complementarity between different energy types and improves the comprehensive utilization efficiency, which is one of the important ways to solve the efficient and clean utilization of coal resources.

[0037] Further, the duration of the heat preservation setting is not less than 20 min, and the heating rate during the step-by-step heating process is 20 - 40 °C / min, ensuring that long-chain organic substances have sufficient pyrolysis time to release all the volatile gas and guaranteeing the accuracy and integrity of data collection. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 It is a schematic structural diagram of an experimental system for coal combustion hybrid pyrolysis to produce nascent semicoke gasification in a specific embodiment of the present invention.

[0039] In the figure: Feed pretreatment device 1, Carrier supply device 2, Feed valve 3, Mixing device 4, Grinding and sieving device 5, Weighing and metering device 6, Nitrogen cylinder 7, Nitrogen valve 8, Carbon dioxide cylinder 9, Carbon dioxide valve 10, Three-way intake valve 11, Mixed sample 12, Nascent semicoke 13, Pyrolysis furnace 14, TG thermal gravimetric analyzer 15, Temperature control heating equipment 16, Thermometer 17, Thermocouple 18, Gas outlet 19, Gas inlet valve of gas collecting cylinder 20, Gas outlet valve of gas collecting cylinder 21, Volatile gas collecting cylinder 22, Analysis unit 23. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0040] The following further elaborates on the present invention in detail with specific embodiments, which is an explanation rather than a limitation of the present invention.

[0041] An experimental system for coal combustion hybrid pyrolysis to produce nascent semicoke gasification in the present invention, as Figure 1As shown in the figure, it includes a pyrolysis furnace 14, a feed pretreatment device 1, and a carrier supply device 2; the side wall of the pyrolysis furnace 14 is connected to the feed pretreatment device 1, the carrier supply device 2, and a temperature control heating device 16; specifically, the air inlet of the pyrolysis furnace 14 is connected to the carrier supply device 2, the feed inlet of the pyrolysis furnace 14 is connected to the discharge port of the feed pretreatment device 1, and the temperature control heating device 16 is connected to the heat input end on the side wall of the pyrolysis furnace 14; at the same time, a partition layer is provided inside the pyrolysis furnace 14, and the feed inlet, air inlet, and heat input end of the pyrolysis furnace 14 are all provided on the side wall on one side of the upper end surface of the partition layer. After the mixed sample 12 enters the inside of the pyrolysis furnace 14, it is received by the partition layer. At the same time, during the pyrolysis process, the carrier gas can fully wrap the mixed sample 12 to be pyrolyzed, and the heat input end of the pyrolysis furnace 14 is close to the partition layer, which can reduce energy loss.

[0042] The input end of the temperature control heating device 16 is respectively connected to the cold end of the thermocouple 18 and the signal output end of the TG thermogravimetric analyzer 15. The hot end of the thermocouple 18 is connected to the pyrolysis furnace 14. When the hot end of the thermocouple 18 collects the temperature inside the pyrolysis furnace 14, it is transmitted to the temperature control heating device 16 connected to the cold end through a lead wire and a measurement circuit. The temperature control heating device 16 compares the data parameters of each stage during the pyrolysis process provided by the TG thermogravimetric analyzer 15 to achieve the regulation of the temperature inside the pyrolysis furnace 14 by the temperature control heating device 16. Specifically, the TG thermogravimetric analyzer 15 is programmed for temperature control, and stores by measuring the relationship between the mass of the substance and temperature or time.

[0043] An air outlet 19 and a thermometer 17 are provided at the top of the pyrolysis furnace 14. The air outlet 19 is successively connected to a volatile fraction collection bottle 22 and an analysis unit 23 to form a structure for collecting, storing, and analyzing the volatile fraction, and later can be quantitatively supplied to the analysis unit 23 according to the analysis requirements; the thermometer 17 monitors the temperature of the volatile fraction at the upper end of the pyrolysis furnace 14.

[0044] A specific embodiment provided by the present invention is that the feed pretreatment device 1 includes a feed valve 3, a mixing device 4, a grinding and sieving device 5, and a weighing and metering device 6 connected in sequence. The output end of the weighing and metering device 6 is connected to the feed inlet of the pyrolysis furnace 14. Among them, mixing, grinding, and sieving can be carried out simultaneously, or can be divided into separate steps of full mixing and grinding and sieving. Separately carried out, finally, a uniform mixed sample 12 needs to be obtained, and the particle size only needs to meet the pyrolysis requirements.

[0045] Another specific embodiment provided by the present invention is that the carrier supply device 2 includes a nitrogen cylinder 7 and a carbon dioxide cylinder 9; a specific embodiment provided by the present invention is that the nitrogen cylinder 7 and the carbon dioxide cylinder 9 are connected in parallel to the carrier air inlet pipe, one end of the carrier air inlet pipe is provided with a three-way air inlet valve 11, and the other end is connected to the pyrolysis furnace 14. Specifically, the three-way air inlet valve 11 is connected to the nitrogen cylinder 7 and the carbon dioxide cylinder 9 respectively, and the air outlet end is connected to the carrier air inlet pipe. Specifically, the nitrogen cylinder 7 is provided with a nitrogen valve 8 and connected to the nitrogen input port of the three-way air inlet valve 11, and the carbon dioxide cylinder 9 is provided with a carbon dioxide valve 10 and connected to the carbon dioxide input port of the three-way air inlet valve 11, so as to supply the carrier inside the pyrolysis furnace 14 during the pyrolysis process.

[0046] Specifically, the gas inlet of the volatile gas collecting bottle 22 is provided with a gas collecting bottle gas inlet valve 20 , and the gas outlet of the volatile gas collecting bottle 22 is provided with a gas collecting bottle outlet valve 21 , which can realize quantitative supply to the next-level analysis unit 23 .

[0047] Specifically, a partition made of high-temperature resistant material is fixedly provided inside the pyrolysis furnace 14 for receiving the mixed sample 12 and providing a pyrolysis reaction platform.

[0048] An experimental method for gasifying fresh semi-coke by coal mixed pyrolysis comprises the following steps:

[0049] Step 1: In a nitrogen atmosphere, the mixed sample 12 is gradually heated to the final temperature of the first stage. During the heating process, unstable volatile gases are precipitated to generate a degassed mixed sample, completing the first stage pyrolysis process.

[0050] Step 2: Under a nitrogen atmosphere, the final temperature of the first stage is maintained, and the degassed mixed sample is kept warm for a first set time. The long-chain organic matter in the degassed mixed sample is pyrolyzed, and a portion of volatile matter is continuously precipitated to produce new semi-coke 13, completing the second stage pyrolysis process;

[0051] Step 3: In a carbon dioxide atmosphere, the fresh semi-coke 13 is subjected to CO2 gasification starting from the final temperature of the first stage and gradually heated to the final temperature of the third stage. The long-chain organic matter in the fresh semi-coke 13 continues to be pyrolyzed, and the remaining part is volatilized and analyzed to generate molten fresh semi-coke, completing the third stage pyrolysis process.

[0052] Step 4: maintaining the final temperature of the third stage for a second set time under a carbon dioxide atmosphere to melt the newly formed semi-coke to form coke, completing the fourth stage pyrolysis process;

[0053] Step 5: Collect and analyze the volatile gases generated in steps 1 to 4.

[0054] Among them, the final temperatures of the first stage and the third stage are obtained through pyrolysis tests using the TG thermogravimetric analyzer 15. Specifically, the final temperature of the first stage does not exceed 600 °C, and the final temperature of the third stage does not exceed 900 °C; the first set duration is not less than 20 min, and the second set duration is not less than 30 min; the heating rate in Step 1 and Step 3 is 20 - 40 °C / min, ensuring that long-chain organic substances have sufficient pyrolysis time to release all volatile gases and guaranteeing the accuracy and integrity of data collection.

[0055] An experimental method for coal combustion hybrid pyrolysis to produce fresh semicoke gasification according to the present invention can be carried out based on an experimental system for coal combustion hybrid pyrolysis to produce fresh semicoke gasification, including the following steps. The feed pretreatment device 1 mixes, grinds, and sieves the samples to form a mixed sample 12 and feeds it into the internal part of the pyrolysis furnace 14. Specifically, the proportion of the mixed sample 12 is configured based on the requirements of the pyrolysis characteristic test of the mixed sample 12. At the same time, the mixing, grinding, and sieving can be carried out simultaneously or divided into separate steps of sufficient mixing and grinding and sieving, carried out separately. Finally, a uniform mixed sample 12 needs to be obtained, and the particle size only needs to meet the pyrolysis requirements. Then, the mixed sample 12 is fed into the pyrolysis furnace 14. <##

[0056] The temperature control heating device 16 provides heat for the pyrolysis furnace 14. At the same time, the thermocouple 18 monitors the temperature inside the pyrolysis furnace 14 in real time and feeds it back to the temperature control heating device 16. The temperature control heating device 16 compares the temperature inside the furnace with the temperature value of the TG thermogravimetric analyzer 15 to regulate the temperature inside the pyrolysis furnace 14; the mixed sample 12 undergoes pyrolysis inside the pyrolysis furnace 14. Specifically, the temperature reference data of the TG thermogravimetric analyzer 15 is the final temperature value obtained through tests in each stage during the pyrolysis process;

[0057] Specifically, the pyrolysis process inside the pyrolysis furnace 14 is as follows:

[0058] In the first stage, the carrier supply device 2 feeds nitrogen into the pyrolysis furnace 14 to form a nitrogen inert atmosphere, and the temperature inside the pyrolysis furnace 14 is gradually heated to 200 - 300 °C to release unstable volatile components and generate a degassed mixed sample, completing the pyrolysis process of the first stage. Specifically, the pyrolysis furnace 14 is internally provided with a heat-resistant material layer, and the mixed sample 12 is placed in the layer. The fresh semicoke 13 and the coke after the reaction during the pyrolysis reaction mainly occur here, which is also the main reaction center for the gasification of the fresh semicoke 13. At the same time, the reaction temperature of the mixed sample 12 inside the pyrolysis furnace 14 feeds back data from the hot end of the thermocouple 18 to the temperature control heating device 16 in real time, and the thermometer 17 installed at the top of the pyrolysis furnace 14 measures the temperature data of the volatile components.

[0059] In the second stage, under a nitrogen atmosphere, maintaining the end of the first stage, the degassed mixed sample is heat-insulated for a first set duration. Fresh semicoke 13 appears in the pyrolysis products, the long-chain organic matter of the mixed sample 12 is pyrolyzed, and a part of the volatile matter continues to be released;

[0060] In the third stage, the carrier supply device 2 introduces carbon dioxide gas into the pyrolysis furnace 14 to form a carbon dioxide atmosphere. Starting from the final temperature of the first stage, the fresh semicoke 13 is gradually heated up to the final temperature of the third stage by CO2 gasification. The long-chain organic matter of the mixed sample 12 continues to be pyrolyzed, and another part of the volatile matter is released. The volatile matter gas generated in this stage is much larger than the volatile matter gas generated in the second stage, and molten fresh semicoke is formed to complete the pyrolysis process of the third stage;

[0061] In the fourth stage, under a carbon dioxide atmosphere, maintaining the final temperature of the third stage for heat insulation for a second set duration, the molten fresh semicoke is converted into coke to complete the gasification process of producing fresh semicoke 13 by mixed pyrolysis. The influence of the pyrolysis temperature on the gasification process becomes smaller;

[0062] Among them, nitrogen and carbon dioxide gases are used as carrier gases in different heating processes and are switched according to needs. Among them, the three-way intake valve 11 can switch different carrier gas atmospheres according to the control of the pyrolysis stage temperature.

[0063] All the pyrolysis volatile matter gases pass through the air outlet 19 of the pyrolysis furnace 14 to the volatile matter collecting bottle 22 and are further analyzed in the analysis unit 23 to obtain the change in the gas volume and calculate the weight loss of the pyrolysis reaction.

[0064] A specific embodiment provided by the experimental method for coal combustion mixed pyrolysis to produce fresh semicoke gasification of the present invention is as follows:

[0065] Step 1: Mix the samples in a certain proportion to form a mixed sample 12, such as lignite and bituminous coal with a ratio of 1:2.5. The mixing ratio is obtained from the characteristic test of mixed pyrolysis and is added into the pyrolysis furnace 14; the temperature control heating device 16 heats the pyrolysis furnace 14, and the heating degree reaches the final temperature preset by the TG thermogravimetric analyzer 15. The final temperature shall not be lower than the pyrolysis temperature corresponding to the fastest pyrolysis rate of the mixed sample 12, such as a final temperature of 600 °C, and the mixed sample 12 is pyrolyzed under programmed temperature control.

[0066] Step 2: In the first stage, programmed temperature rise mixed pyrolysis. The heating rate is controlled at 20 °C / min, the carrier gas is nitrogen, and it is heated to a set temperature. For example, a temperature between 100 - 600 °C is selected as the final temperature of 600 °C. Usually, in the range of 200 - 300 °C, light and unstable volatile matter gradually precipitates, especially some low-quality fossil fuels such as low-quality coal and oil shale that are prone to precipitate volatile matter at low temperatures, generating a degassed mixed sample.

[0067] Step 3: Second stage, isothermal mixed pyrolysis. Heat and hold at a certain temperature for a period of time to allow the reaction to proceed fully. For example, react at a constant 600 °C for about 20 min in a nitrogen atmosphere, which is the first set duration. Eventually, the long-chain organic matter is completely pyrolyzed, and newly formed semi-pyrolyzed semi-coke is produced, with some volatile components released. At low temperatures, the synergistic effect of the mixed pyrolysis is not obvious.

[0068] Step 4: Third stage, programmed temperature mixed gasification of the newly formed semi-coke 13. Close the nitrogen valve 8 of the carrier supply device 2 and open the carbon dioxide gas valve 10 to change the inert gas nitrogen pyrolysis atmosphere to a carbon dioxide pyrolysis atmosphere, and start the CO2 gasification temperature increase process of the newly formed semi-coke 13. Control the heating rate at about 20 °C / min and heat to the set temperature. For example, select a temperature between 600 - 900 °C and set the final temperature to 900 °C. The volatile components released from the sample increase significantly. As the temperature rises, the long-chain organic matter that was not fully pyrolyzed in the above two stages starts to pyrolyze, and more volatile components are released, generating molten newly formed semi-coke.

[0069] Step 5: Fourth stage, isothermal mixed gasification. Specifically, it is the constant temperature reaction stage. In the above carbon dioxide pyrolysis atmosphere, hold at the set final temperature for a period of time, which is the second set duration. For example, react at a constant 900 °C for about 30 min. At this time, the influence of the pyrolysis temperature on the gasification behavior becomes smaller, and the molten newly formed semi-coke turns into coke.

[0070] Specifically, according to the actual situation, different heating rates can be selected for each step, such as a heating rate of 20 - 40 °C / min; the above steps are also suitable for the CO2 gasification characteristics of semi-coke from coal coupled with different fuels, such as the gasification of pyrolyzed semi-coke from bituminous coal coupled with oil shale, etc.; different pyrolysis final temperatures and the set duration of heat preservation are set according to the pyrolysis characteristics of the mixed sample 12. It is recommended that the final temperature of the first stage heating be set lower than the fastest pyrolysis rate of the mixed sample 12 to complete the gasification process of producing newly formed semi-coke 13 from coal mixed pyrolysis.

Claims

1. An experimental system for gasification of newly formed semi-coke by coal combustion and mixed pyrolysis, characterized in that, It includes a pyrolysis furnace (14), a feed pretreatment device (1), and a carrier supply device (2); The side wall of the pyrolysis furnace (14) is connected to a feed pretreatment device (1), a carrier supply device (2), and a temperature control heating device (16); The top gas outlet (19) of the pyrolysis furnace (14) is sequentially connected to a volatile fraction collection bottle (22) and an analysis unit (23); it is used for storing and analyzing the volatile substances generated by pyrolysis; The input end of the temperature control heating device (16) is respectively connected to the cold end of a thermocouple (18) and the signal output end of a TG thermogravimetric analyzer (15), and the hot end of the thermocouple (18) is connected to the pyrolysis furnace (14); the temperature control heating device (16) is used for comparing the collected temperature with the temperature obtained through experiments by the TG thermogravimetric analyzer, and adjusting the temperature during the pyrolysis process of the pyrolysis furnace; There is a partition layer inside the pyrolysis furnace (14) for carrying a mixed sample (12); the connection ends of the feed pretreatment device (1), the carrier supply device (2), and the thermocouple (18) with the pyrolysis furnace (14) are respectively arranged corresponding to the carrying positions of the mixed sample (12); The carrier supply device (2) includes a nitrogen gas cylinder (7) and a carbon dioxide gas cylinder (9); The nitrogen gas cylinder (7) and the carbon dioxide gas cylinder (9) are respectively connected to two input ends of a three-way inlet valve (11), and are respectively used as carrier gases during different heating processes. The output end of the three-way inlet valve (11) is connected to the pyrolysis furnace (14), and the three-way inlet valve (11) switches different carrier gas atmospheres according to the control of the pyrolysis stage temperature; The pyrolysis furnace (14) is used to complete a four-stage pyrolysis process, generate coke from the molten fresh semicoke, and collect and analyze the volatile gases generated in the four stages.

2. The experimental system for gasification of newly formed semi-coke by coal combustion and mixed pyrolysis according to claim 1, wherein The feed pretreatment device (1) includes a feed valve (3), a mixing device (4), a grinding and sieving device (5), and a weighing and metering device (6) connected in sequence, and the discharge port of the weighing and metering device (6) is connected to the pyrolysis furnace (14).

3. The experimental system for gasification of newly formed semicoke by coal combustion and mixed pyrolysis according to claim 1, wherein A thermometer (17) is arranged at the top of the pyrolysis furnace (14) to detect the temperature of the volatile gas.

4. A test method for gasification of newly produced semi-coke by coal-fired hybrid pyrolysis, characterized in that, It includes the following steps: Step 1, under a nitrogen atmosphere, gradually heat the mixed sample (12) to the final temperature of the first stage. During the heating process, unstable volatile gases are precipitated to generate a degassed mixed sample, and the first-stage pyrolysis process is completed; Step 2, under a nitrogen atmosphere, maintain the final temperature of the first stage, keep the degassed mixed sample at a constant temperature for a first set time. The long-chain organic substances in the degassed mixed sample are pyrolyzed, and a part of the volatile matter continues to precipitate to generate fresh semicoke (13), and the second-stage pyrolysis process is completed; Step 3, under a carbon dioxide atmosphere, start to carry out CO2 gasification on the fresh semicoke (13) from the final temperature of the first stage and gradually heat it to the final temperature of the third stage. The long-chain organic substances in the fresh semicoke (13) continue to be pyrolyzed, and the remaining part of the volatile matter is precipitated to generate molten fresh semicoke, and the third-stage pyrolysis process is completed; Step 4, under a carbon dioxide atmosphere, maintain the final temperature of the third stage for heat preservation for a second set time, and the molten fresh semicoke generates coke, and the fourth-stage pyrolysis process is completed; Step 5: Collect and analyze the volatile gases generated in Steps 1 to 4.

5. The experimental method for gasifying the newly produced semi-coke by coal combustion mixed pyrolysis according to claim 4, characterized in that, The final temperatures of the first stage and the third stage are obtained through pyrolysis tests using a TG thermal decomposition thermogravimetric analyzer (15).

6. The test method for gasification of newly formed semicoke by coal-fired hybrid pyrolysis according to claim 4, characterized in that The final temperature of the first stage does not exceed 600 °C, and the final temperature of the third stage does not exceed 900 °C.

7. The experimental method for gasifying newly formed semicoke by coal combustion and mixed pyrolysis according to claim 6, characterized in that, The range of the final temperature of the first stage is 200 - 300 °C.

8. The test method for gasification of newly produced semicoke by coal combustion mixed pyrolysis according to claim 4, characterized in that, The first set duration is not less than 20 min, and the second set duration is not less than 30 min.

9. The experimental method for gasifying newly produced semi-coke by coal combustion hybrid pyrolysis according to claim 4, characterized in that, The heating rate in Steps 1 and 3 is 20 - 40 °C / min.

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