An X-type flame gasifier and its design and operation methods

Abstract

The present invention discloses an X-type flame gasifier and its design and operation methods. The X-type flame gasifier includes a gasifier shell, a gasification chamber, and a slag pool. The gasification chamber is arranged at the upper part of the furnace body, and the slag pool is arranged at the bottom of the furnace body. A slag outlet is arranged at the bottom of the gasification chamber. The diameter of the gasification chamber gradually decreases from top to bottom above the slag outlet to form a slope. Burners are arranged symmetrically along the axis of the gasifier on the slope. The outlet of the burner faces obliquely upward to the inside of the gasification chamber. The outside of the gasification chamber is surrounded by a water-cooled wall, and a quench sleeve is arranged below the slag outlet; a syngas outlet is arranged on the furnace body; the fuel is sprayed obliquely upward into the gasifier through the burners arranged at the slope position at the bottom of the gasifier. After the jets of different burners come into contact, the jet direction changes, forming a quasi-X flame. The syngas is discharged from the bottom of the gasification chamber, greatly increasing the particle residence time, improving the carbon conversion rate and cold gas efficiency. The syngas flows towards the outlet, heating the pulverized coal entering the furnace and the liquid slag layer at the outlet, which can accelerate ignition, reduce slagging at the slag outlet, and improve the coal type adaptability.

Description

Technical Field

[0001] The present invention belongs to the new large-scale pressurized entrained flow gasification technology in the energy field, and particularly relates to a pressurized entrained flow gasification device. Background Art

[0002] Coal gasification technology is the basis for the development of modern chemical industry and one of the key technologies for the clean and efficient utilization of carbon-based solid fuels. According to the mixing method of coal and gasifying agent, coal gasification technology is divided into three types: fixed bed, fluidized bed and entrained flow bed. The entrained flow bed gasification technology has good coal type adaptability, high carbon conversion rate and is easy to scale up, so it has been widely used. There are mainly two representative entrained flow bed gasification technologies. One is the top-sprayed water coal slurry gasification furnace represented by Texaco and East China University of Science and Technology in China, and the other is the bottom-sprayed dry pulverized coal gasification furnace represented by Shell and Xi'an Thermal Power Research Institute. The Texaco gasification furnace adopting the top-spray scheme is prone to short-circuit phenomenon and large jet recirculation zone, which reduces the carbon conversion rate and the service life of the fuel burner at the same time. The multi-burner gasification furnace technology of East China University of Science and Technology has improved the carbon conversion rate and equipment availability to a certain extent. However, due to the opposed arrangement of side burners, an obvious flame will be formed after the jet impingement combustion. The impinging flame directly threatens the service life of the refractory material at the top of the gasification furnace upwards, and due to operation problems, the flame center may deviate from the central axis of the gasification furnace, and the fuel burner will be burned out due to being too close to the flame. In the Shell gasification furnace and the two-stage dry pulverized coal gasification furnace, the cold gas and molten slag flow in reverse. Fine slag in the syngas is easily carried by the syngas stream into the syngas cooler and subsequent cooling and purification equipment, which may cause ash accumulation and blockage in the subsequent equipment and pipelines. The above-mentioned pressurized entrained flow gasification furnaces all adopt the liquid slag discharge method, which has strict requirements on the ash fusion temperature of the coal entering the furnace. Generally, it is required that the ash fusion temperature FT is lower than 1400 °C, otherwise slag blocking is likely to occur, and the coal type adaptability is poor. Due to the short residence time, the gasification effect of poor coals and other difficult-to-gasify coals is poor.

[0003] Therefore, it is necessary to develop a gasification furnace and a gasification furnace design and operation method with a long residence time in the furnace, a uniform temperature field and a high slag discharge temperature, so as to improve the carbon conversion rate, reduce slag blocking and ash accumulation, and improve the gasification ability for difficult-to-gasify coals. Summary of the Invention

[0004] In order to solve the problems existing in the prior art, the present invention provides an X-type flame gasification furnace and its design and operation method, which has a long residence time in the furnace, a reasonable temperature field and a high slag discharge temperature, and can improve the carbon conversion rate, reduce slag blocking and ash accumulation, and improve the gasification ability for difficult-to-gasify coals.

[0005] To achieve the above object, the technical solution adopted by the present invention is: an X-type flame gasifier, including a gasifier shell, a gasification chamber, and a slag pool. The gasification chamber is arranged at the upper part of the furnace body, the slag pool is arranged at the bottom of the furnace body, a slag outlet is arranged at the bottom of the gasification chamber, and the diameter of the gasification chamber gradually decreases from top to bottom above the slag outlet to form a slope. Burners are arranged symmetrically along the axis of the gasifier on the slope, and the outlet of the burner faces obliquely upward inside the gasification chamber. The outside of the gasification chamber is surrounded by a water-cooled wall, and a quench sleeve is arranged below the slag outlet; a syngas outlet is arranged on the furnace body.

[0006] The diameter D of the gasification chamber is calculated as follows:

[0007]

[0008] In the formula, q1 represents the gasification intensity, which is calculated as The gasification intensity is related to coal quality characteristics, types and supply amounts of gasifying agents, operating conditions, and gasifier structure factors. Referring to a two-stage pressurized dry powder gasifier, the value is 8780.8 kg / (m 2 ·h); V g is the gas production rate, that is, the volume of syngas converted per kilogram of fuel after gasification, which is determined through trial burning experiments; V is the single-furnace production capacity, which is determined by the construction requirements of the gasifier.

[0009] The burner adopts a concentric circle structure. The inner circle is connected to the pulverized coal and carrier gas pipelines, and the circular ring is connected to the gasifying agent pipeline. The gasifying agent is pure oxygen and steam. The carrier gas flow rate is 20 - 30 m / s, the gasifying agent flow rate is 30 - 40 m / s, and the diameters of the inner circle and the circular ring are determined by V and the gas flow rate.

[0010] The elevation angle β of the burner is adjustable, and the angle α between the projection of the axis of the burner in the horizontal direction and the radius of the horizontal cross-section circle is adjustable.

[0011] The slope is a conical surface, and the included angle between the generatrix of the conical surface and the axis of the gasifier is 20° - 70°.

[0012] The number of burners is 3 - 6; the distance between the burner and the vertical wall surface is 0.4 - 0.6 of the slope length, and they are evenly distributed at the same height.

[0013] The syngas outlet is located at the top of the gasifier, and a soot blower is arranged. A gas analyzer is arranged at the syngas outlet; a black water outlet and a slag water outlet are provided at the bottom of the slag pool, and the height of the black water outlet is higher than the height of the slag water outlet.

[0014] The operation method of the X-type flame gasifier described in the present invention is as follows: pulverized coal enters the gasifier through a burner in the form of water-coal slurry or dry pulverized coal. The pulverized coal particles move upward under the action of the jet generated by the burner, and then move downward with the syngas to the slag outlet. During the downward movement of the pulverized coal, part of it is entrained and broken by the incoming jet. The syngas leaving the slag outlet enters the syngas outlet, and part of the fly ash falls into the slag pool under the action of centrifugal force and gravity. The flow directions of the syngas and the liquid slag are the same.

[0015] The design method of the X flame gasifier described in the present invention is as follows: determine the gasifier diameter and burner diameter parameters according to the single-furnace production capacity and coal quality parameters to obtain the initial model and boundary conditions of the gasifier; establish a fluent model, and use sub-models such as the k-ε model, DO model, and RPM model to calculate the flow and chemical reactions in the furnace. Input the wall temperature and heat flux density into the slag layer flow calculation process, and calculate the distribution characteristics and temperature distribution of the wall slag layer according to the temperature field and coal slag parameters of the fluent program, and input them into the fluent model for iteration; when the parameter difference calculated by the two models is less than 0.5%, it is considered that the iteration converges; change parameters such as the gasifier height, and calculate the carbon conversion rate and cold gas efficiency to obtain the optimal solution, and calculate the final design values of the gasifier parameters.

[0016] After the gasifier operates, read the water vapor density of the water-cooled wall and the syngas composition parameters, and correct the gasifier operation parameters based on the water vapor density of the water-cooled wall and the syngas composition parameters; the gasifier is provided with a control center, and the control center predicts operation failures in a timely manner by comparing the real-time parameters with the calculation data of the fluent model, and eliminates the failures by controlling the burner deflection angle in real time to change the in-furnace field distribution. At the same time, predict the optimal value of the burner deflection angle under variable conditions, and maintain the safe and stable operation of the gasifier by controlling the temperature field data under different conditions; when the control center is idle, automatically perform variable parameter calculations to optimize the existing gasifier to assist in the maintenance and transformation of the gasifier; the operation system combines the fluent calculation data with the real-time data to realize the visualization of the gasification situation and slag layer distribution in the furnace.

[0017] Compared with the prior art, the present invention has at least the following beneficial effects:

[0018] This gasifier innovatively adopts the X-flame gasification method. The fuel enters the furnace in the form of X-flames through multiple fuel burners symmetrically arranged along the central axis of the gasifier at the bottom slope of the gasification chamber. The pulverized coal particles move upward under the action of the jet generated by the burners on the slope, which can greatly extend the residence time of carbon particles in the furnace, enhance the turbulence intensity of the pulverized coal airflow in the furnace, improve the carbon conversion rate and cold gas efficiency. During the downward movement of the pulverized coal, it may be entrained and broken by the incoming jet, further increasing the carbon conversion rate and cold gas efficiency, increasing the adaptability to difficult-to-burn coal types. The synthesis gas and the liquid slag flow in the same direction, which is beneficial to increasing the temperature of the liquid slag at the slag outlet position. Coupled with the heating effect of the synthesis gas, it promotes the flow of the liquid slag, effectively preventing the occurrence of phenomena such as slagging and blockage at the gasification chamber outlet, and increasing the adaptability to high ash melting point coal types.

[0019] Furthermore, under different operating conditions, the deflection angles of the burners to achieve the ideal residence time and gasification performance may vary. Real-time adjustment can reduce coal consumption, save energy and reduce emissions, and increase economic benefits.

[0020] Furthermore, through the combined action of adjusting the α angle, the synthesis gas outlet position and the soot blower, the fly ash of the gasifier is reduced, protecting the synthesis gas cooler and purification equipment. Thus, it further expands the coal type adaptability and improves the availability of the gasifier. It is a new type of pressurized entrained flow gasification technology with high coal type adaptability, high carbon conversion rate, and high cold gas efficiency. Furthermore, the flame temperature and flame position in the gasification chamber are adjusted by controlling the burner direction. Brief Description of the Drawings

[0021] Figure 1 It is a schematic structural diagram of an X-type flame gasifier of the present invention.

[0022] Figure 2 It is Figure 1 the schematic cross-sectional view taken along the A-A direction in

[0023] Figure 3 a flow chart of the design and operation method of an X-type flame gasifier;

[0024] Figure 4 It is the cloud diagram of the particle and velocity distribution and the cloud diagram of the particle trajectory in the furnace when the height-to-diameter ratio of the X-type flame gasifier is 1 and the elevation angle is 60°;

[0025] Figure 5 It is the cloud diagram of the particle and velocity distribution and the cloud diagram of the particle trajectory in the furnace when the height-to-diameter ratio of the X-type flame gasifier is 0.79 and the elevation angle is 60°;

[0026] Figure 6 It is the cloud diagram of the temperature distribution in the furnace when the height-to-diameter ratio of the X-type flame gasifier is 0.79 and the elevation angles are 60° and 45° respectively;

[0027] In the figure: gasifier shell 1, water-cooled wall 2, gasification chamber 3, pulverized coal jet 4, slope 5, burner 6, quench sleeve 7, slag pool 8, black water outlet 9, slag water outlet 10, slag opening 11, soot blower 12, syngas outlet 13, gas analyzer 14. Detailed implementation manners

[0028] For a better understanding of the technical solution of the present invention, the following will describe in detail the specific implementation manners of the present invention with reference to the accompanying drawings:

[0029] Refer to the attached Figure 1 , an X-type flame gasifier of the present invention includes a gasifier shell 1, a gasification chamber 3, and a slag pool 8. The gasification chamber 3 is arranged at the upper part of the furnace body, and the slag pool 8 is arranged at the bottom of the furnace body. A slag opening 11 is arranged at the bottom of the gasification chamber 3. The diameter of the gasification chamber gradually decreases from top to bottom above the slag opening 11 to form a slope 5. Burners 6 arranged symmetrically along the axis of the gasifier are provided on the slope 5. The outlet of the burner 6 faces obliquely upward inside the gasification chamber. The outside of the gasification chamber 3 is surrounded by a water-cooled wall 2. A quench sleeve 7 is arranged below the slag opening 11; a syngas outlet 13 is arranged on the furnace body; wherein, the gasification chamber 3 and the slag opening adopt a membrane water-cooled wall structure; the axis of the fuel burner 6 forms an angle with the central axis of the gasifier; adopting this technical solution, the fuel (dry pulverized coal / water coal slurry) is sprayed obliquely upward into the gasification chamber 3 through the fuel burner 6 arranged on the slope 5 of the gasifier, and undergoes partial combustion and gasification reactions with the simultaneously sprayed oxygen and steam. After the pulverized coal gas stream ignites, it extends upward and rises along the central axis to form an X-type flame. Then, the syngas flows downward through the slag opening 11 and is discharged from the syngas outlet 13. This new X-flame gasification method greatly prolongs the residence time of coal char particles in the furnace, increases the slag discharge temperature, enhances the turbulence intensity of the pulverized coal gas stream in the furnace, greatly improves the carbon conversion rate and cold gas efficiency, and reduces the probability of slag blockage.

[0030] The diameter D of the gasification chamber 3 is calculated as follows In the formula, q1 represents the gasification intensity kg / (m 2 ·h), and is calculated as The gasification intensity is related to factors such as coal quality characteristics, types and supply amounts of gasification agents, operating conditions, and gasifier structure. The value of 8780.8 kg / (m 2 ·h) can be referred to for a two-stage pressurized dry powder gasifier; V g is the gas production rate m 3 / kg, that is, the volume of syngas converted per kilogram of fuel after gasification, which is determined through trial burning experiments; V is the single-furnace production capacity m 3 / h, which is determined by the construction requirements of the gasifier.

[0031] The inlet burner 6 adopts a concentric circle structure. The inner circle is connected to the pulverized coal and carrier gas pipelines, and the annular circle is connected to the gasifier agent pipeline. The gasifier agent is pure oxygen and steam. The carrier gas flow rate is 20 - 30 m / s, the gasifier agent flow rate is 30 - 40 m / s, and the diameters of the inner circle and the outer circle are determined by V and the gas flow rate.

[0032] The fuel burner 6 is set to be swingable or has an adjustable angle during installation, so the angle between the axis of the fuel burner 6 and the central axis of the gasifier can be adjusted. With this technical solution, the gasifier can adjust the elevation angle of 45 - 80° and the α angle of 0 - 5° of multiple burners 6 arranged on the slope according to the coal quality of the coal entering the furnace, so as to adjust the position of the flame center and the outlet temperature in the gasification chamber, and to a certain extent, expand the adaptability of the gasifier to coal types; The syngas has the function of heating the liquid slag at the slag tap 11, reducing the slag viscosity, reducing the requirement for the viscosity-temperature characteristics of the coal slag, and can further improve the coal type adaptability.

[0033] As a preferred embodiment, the gasification chamber adopts a water-cooled wall 2 to avoid the problem of burning of refractory bricks and enhance the availability.

[0034] As an optimizable structure, the adjustment of the angle α can promote the formation of a rotating flow field in the furnace, enable the liquid slag to be captured by the wall surface, reduce the amount of fly ash, and reduce the load of the subsequent syngas cooler and purification equipment.

[0035] As an optional embodiment, the number of burners 6 is 3 - 6 and they are evenly distributed at the same height.

[0036] The syngas outlet 13 is located at the top of the gasifier, and a soot blower 12 is arranged at the syngas outlet 13. The syngas outlet 13 is also connected to a gas analyzer 14 to collect the syngas data at the outlet in real time.

[0037] The high-temperature ash slag formed by partial combustion and gasification of the fuel in the gasification chamber 3 enters the connected slag pond 8 through the slag tap 11. After being cooled and solidified in the slag pond, it is deposited at the slag water outlet 10. After being further crushed by the slag crusher at the bottom of the slag water outlet 10, it enters the slag locking tank and is then regularly discharged outside the gasifier through the slag discharge port of the slag locking tank; The unreacted carbon particles in the raw gas flowing downward from the top of the gasification chamber 3 continue to react with gasifier agents such as CO2 and steam. The carbon particle ash slag with a larger particle size is impacted by the X flame gas flow and continues to burn and break. The broken fine particles may be carried to the upper part of the gasification chamber 3 to continue gasification, thereby further improving the carbon conversion efficiency of the entire gasifier.

[0038] The high-temperature syngas from the gasification chamber passes through the quench jacket 7 arranged below the slag tap 11 to cool the high-temperature syngas, and at the same time by-product high-pressure / medium-pressure steam is produced to improve the overall energy utilization efficiency. The high-temperature syngas from the slag tap 11 has a large angle with the syngas outlet 13, and the coal ash with larger particles falls into the slag pool 8 under the action of gravity, so that the fly ash in the syngas is effectively separated, effectively preventing large-particle fly ash from entering the downstream and avoiding the occurrence of blockage of the convective waste heat boiler heating surface.

[0039] The present invention also provides a design method for an X-type flame gasifier, which is specifically implemented as follows. Initial conditions such as the single-furnace production capacity and coal quality parameters are obtained according to requirements to determine parameters such as the gasifier diameter and burner diameter, and an initial model and boundary conditions of the gasifier are obtained; a fluent model is established, and common sub-models such as the k-ε model, DO (discrete ordinates) model, RPM (random pore model), etc. are used to calculate the flow and chemical reactions in the furnace. The calculation process of the slag layer flow is programmed to obtain a slag layer flow calculation program, and the wall temperature, heat flux density, etc. are input into the slag layer flow calculation program; a slag layer flow calculation program is written using MATLAB or C language, etc. According to the temperature field of the fluent program and coal slag parameters, etc., the distribution characteristics and temperature distribution of the wall slag layer are calculated and input into fluent for iteration. When the difference between the parameters calculated by the two programs is less than 0.5%, it is considered that the iteration converges; parameters such as the height of the gasifier are changed, and key parameters such as carbon conversion rate and cold gas efficiency are calculated to obtain the optimal solution. The best values of parameters such as the height of the gasifier are calculated by the program.

[0040] The operation method of the X-type flame gasifier provided by the present invention is specifically as follows. After the gasifier operates, parameters such as the measurable water vapor density of the water-cooled wall and the removal of moisture from the syngas composition are read to realize the correction of the industrial operation values for the calculation parameters of the fluent model and the rheological characteristics of the slag layer; the fluent model and the slag layer rheological characteristics calculation program operate in the control center. The control center has an outlier alarm function and a machine learning function, and can predict faults such as slag blockage in time by comparing the real-time parameters with the calculation data of the fluent model, etc. By controlling the burner deflection angle in real time, the furnace internal field distribution is changed to eliminate the faults, and at the same time the optimal value of the burner deflection angle under variable working conditions is predicted. Through data such as the temperature field under different working conditions, the water-cooled wall is prevented from burning out and the safe and stable operation of the gasifier is maintained. When the control center is idle, it automatically performs variable parameter calculations to optimize the existing gasifier to assist in the overhaul and transformation of the gasifier. The operation system will also combine the data calculated by the fluent model with the real-time data to realize the visualization of the gasification situation and slag layer distribution in the furnace.

[0041] Specific implementation plan

[0042] A design method for an X-type flame gasifier of the present invention is specifically implemented as follows: When designing the gasifier according to the present invention, taking a certain IGCC power plant as an example, the amount of pulverized coal input into the gasifier is 58,802 kg / h. According to the formula Calculating, the diameter of the gasifier is approximately 2.92 m. Taking the ratio of the height to the diameter of the vertical water-cooled wall of the gasifier as 1, and referring to the parameters such as the diameter of the gasifier burner and the oxygen-coal ratio of the two-stage pressurized dry powder gasifier, a preliminary structural scheme of the gasifier is obtained. The geometric model and calculation model of the gasifier are imported into the fluent software, and the gasification performance and field distribution of this preliminary scheme are calculated, such as Figure 4 The elevation angle of the burner is 60°. Figure 4 (a) It can be seen that the particle distribution in the X-type flame gasifier is uniform, and the particles are in good contact with the gasifying agent; Figure 4 (b) and Figure 4 (c) It can be seen that the gas flow velocity at the top of the gasifier is relatively low, and the particles are not easily introduced into the top area of the gasifier, and the flow field distribution is unreasonable. Therefore, further, the height of the gasifier can be reduced for optimization design, and the height-diameter ratio is reduced to 0.79. The calculation results are as shown in Figure 5 (a), Figure 5 (b) and Figure 5 (c). It can be seen that the uniformity of the particle distribution is still good. At the same time, the gas flow velocity at the top of the gasifier increases, and the particles enter the top of the gasifier under the action of the gas flow, which is conducive to the rational utilization of the internal space of the gasifier, reduces the area of the water-cooled wall, increases the temperature in the furnace, and promotes the occurrence of the gasification reaction. According to this method, the slope angle of the gasifier, the position of the burner, etc. are simulated in turn, and the structure of the X-type flame gasifier is designed and optimized to promote the rational design and implementation of this new type of gasifier.

[0043] An operation method for an X-type flame gasifier of the present invention is specifically implemented as follows: The angle of the burner in the furnace can be adjusted under the control of the control center. The control center adjusts the burner to the most suitable angle according to changes in coal quality, load changes, outlet syngas, slagging conditions, etc., so as to achieve effects such as improving the carbon conversion rate of the gasifier and reducing slagging. Taking the example of increasing the temperature of the slag discharge port of the gasifier to prevent slagging, in the operation method of an X-type flame gasifier of the present invention, when it is detected that the slag thickness at the slag port is relatively high, the elevation angle of the burner is reduced from 60° to 45°. The temperature distributions at the slag port before and after the adjustment are respectively as shown in Figure 6 (a) and Figure 6 (b). It can be seen that the temperature at the slag port position increases significantly. This method can effectively predict and prevent slagging without changing the oxygen-coal ratio, and promotes the safe and stable operation of the gasifier.

[0044] In summary, the present invention provides an X-type flame gasifier, which includes a gasifier shell, a gasification chamber, and a slag pool. The gasification chamber is arranged at the upper part of the furnace body, and the slag pool is arranged at the bottom of the furnace body. A slag outlet is arranged at the bottom of the gasification chamber. The diameter of the gasification chamber gradually decreases from top to bottom above the slag outlet to form a slope. Nozzles symmetrically arranged along the axis of the gasifier are provided on the slope. The outlet of the nozzle faces obliquely upward inside the gasification chamber. The gasification chamber is surrounded by a water-cooled wall, and a quench sleeve is arranged below the slag outlet. A syngas outlet is provided on the furnace body. The fuel is sprayed obliquely upward into the gasifier through the nozzles arranged at the slope position at the bottom of the gasifier. After the jets of different nozzles contact, the jet direction changes, forming a similar X flame. The syngas is discharged from the bottom of the gasification chamber, greatly increasing the particle residence time, improving the carbon conversion rate and cold gas efficiency. The syngas flows towards the outlet, having the function of heating the pulverized coal entering the furnace and the liquid slag layer at the outlet, being able to accelerate ignition, reduce slagging at the slag outlet, and improve the coal type adaptability.

Claims

1. An X-type flame gasifier, characterized in that: It includes a gasifier shell (1), a gasification chamber (3), and a slag pool (8). The gasification chamber (3) is arranged at the upper part of the furnace body, and the slag pool (8) is arranged at the bottom of the furnace body. A slag outlet (11) is arranged at the bottom of the gasification chamber (3). The diameter of the gasification chamber gradually decreases from top to bottom above the slag outlet (11) to form a slope (5). Burners (6) arranged symmetrically along the axis of the gasifier are provided on the slope (5). The outlet of the burner (6) faces obliquely upward towards the inside of the gasification chamber. The water-cooled wall (2) surrounds the outside of the gasification chamber (3). A quench sleeve (7) is arranged below the slag outlet (11); a syngas outlet (13) is provided on the furnace body.

2. The X-type flame gasifier according to claim 1, characterized in that: The diameter D of the gasification chamber (3) is calculated as follows: In the formula, q1 represents the gasification intensity, which is calculated as The gasification intensity is related to coal quality characteristics, types and supply amounts of gasifying agents, operating conditions, and gasifier structure factors; V g is the gas production rate, that is, the volume of syngas converted after gasifying per kilogram of fuel, which is determined through trial burning experiments; V is the single furnace production capacity, which is determined by the construction requirements of the gasifier.

3. The X-type flame gasifier according to claim 1, characterized in that: The burner (6) adopts a concentric circle structure. The inner circle is connected to the pulverized coal and carrier gas pipelines, and the ring is connected to the gasifying agent pipeline. The gasifying agent is pure oxygen and steam. The carrier gas flow rate is 20 - 30 m / s, the gasifying agent flow rate is 30 - 40 m / s, and the diameters of the inner circle and the ring are determined by V and the gas flow rate.

4. The X-type flame gasifier according to claim 1, characterized in that: The elevation angle β of the burner (6) is adjustable, and the angle α between the projection of the axis of the burner (6) in the horizontal direction and the radius of the horizontal cross-sectional circle is adjustable.

5. The X-type flame gasifier according to claim 1, characterized in that: The slope (5) is a conical surface, and the angle between the generatrix of the conical surface and the axis of the gasifier is 20° - 70°.

6. The X-type flame gasifier according to claim 1, wherein: The number of the burners (6) is 3 - 6; the distance between the burner (6) and the vertical wall surface is 0.4 - 0.6 of the slope length, and they are evenly distributed at the same height.

7. The X-type flame gasifier according to claim 1, characterized in that: The syngas outlet (13) is located at the top of the gasifier, and a soot blower (12) is arranged. A gas analyzer (14) is provided at the syngas outlet (13); a black water outlet (9) and a slag water outlet (10) are provided at the bottom of the slag pool (8), and the height of the black water outlet (9) is higher than the height of the slag water outlet (10).

8. The operation method of the X-type flame gasifier according to any one of claims 1 to 7, characterized in that: The pulverized coal enters the gasifier from the burner (6) in the form of water - coal slurry or dry pulverized coal. The pulverized coal particles move upward under the action of the jet generated by the burner (6), and then follow the syngas downward to the slag outlet (11). During the downward movement of the pulverized coal, part of it is entrained and broken by the incoming jet. The syngas leaving the slag outlet (11) enters the syngas outlet (13), and part of the fly ash falls into the slag pool (8) under the action of centrifugal force and gravity; the flow directions of the syngas and the liquid slag are the same.

9. The design method of the X-type flame gasifier according to any one of claims 1 to 7, characterized in that: Determine the gasifier diameter and burner diameter parameters according to the single - furnace production capacity and coal quality parameters to obtain the initial model and boundary conditions of the gasifier; establish a fluent model, and use sub - models such as the k - ε model, DO model, or RPM model to calculate the flow and chemical reactions in the furnace. Input the wall temperature and heat flux density into the slag layer flow calculation process, calculate the distribution characteristics and temperature distribution of the wall slag layer according to the temperature field and coal slag parameters of the fluent program, input them into the fluent model, and perform iteration; when the difference between the parameters of two adjacent iterative calculations is less than 0.5%, it is considered that the iteration converges; change the height of the gasifier, calculate the carbon conversion rate and cold gas efficiency to obtain the optimal solution, and calculate the final design values of the gasifier parameters.

10. The operating method of the X-type flame gasifier according to claim 8, characterized in that: After the gasifier runs, read the water vapor density of the water-cooled wall and the synthesis gas composition parameters, and correct the operating parameters of the gasifier based on the water vapor density of the water-cooled wall and the synthesis gas composition parameters; the gasifier is provided with a control center, and the control center timely predicts operating faults by comparing real-time parameters with the calculation data of the fluent model, eliminates faults by controlling the deflection angle of the burner in real time to change the field distribution in the furnace, and at the same time predicts the optimal value of the burner deflection angle under variable operating conditions, and maintains the safe and stable operation of the gasifier by controlling the temperature field data under different operating conditions; when the control center is idle, it automatically performs variable parameter calculations to optimize the existing gasifier to assist in the overhaul and transformation of the gasifier; the operation system combines the fluent calculation data with the real-time data to realize the visualization of the gasification situation and slag layer distribution in the furnace.

Images