Method and system for promoting rapid carbonation of circulating fluidized bed boiler ash

Abstract

This invention relates to an improved method for circulating fluidized bed boilers, and more particularly to a method and system for promoting rapid carbonization of ash and slag in circulating fluidized bed boilers. The method includes the following steps: S1 Mixing circulating fluidized bed boiler ash and slag with water, stirring until homogeneous, to obtain a mixture; S2 Introducing a gas containing carbon dioxide, maintaining the temperature at 20-160℃, to carry out carbonization; S3 During the carbonization process, adjusting the ratio of the thickness of the stationary layer to the thickness of the moving layer in the mixture, i.e., reducing the thickness of the stationary layer and increasing the thickness of the moving layer, improves the degree of carbonization. This invention, through dual innovations in quantitative gas control and structured material movement design, not only significantly improves the efficiency and economy of the carbonization process of circulating fluidized bed boiler ash and slag, but also achieves proactive and precise control over the quality and performance of the carbonization products, possessing significant industrial application value.

Description

Technical Field

[0001] This invention relates to a control method for a circulating fluidized bed boiler, and more particularly to a method and system for promoting rapid carbonization of ash and slag in a circulating fluidized bed boiler. Background Technology

[0002] Circulating fluidized bed (CFB) boilers, as core equipment for clean and efficient coal combustion in my country, have been widely used in power generation, heating, and chemical production. However, during the operation of CFB boilers, if in-furnace desulfurization or tail-end semi-dry desulfurization processes are used, the resulting ash exhibits significant high-calcium and high-sulfur chemical characteristics. This characteristic makes it difficult to utilize the ash on a large scale in traditional building materials and construction industries, becoming a bottleneck for the development of CFB boiler-powered thermal power plants or combined heat and power plants.

[0003] High-sulfur, high-calcium circulating fluidized bed boiler ash, when used in traditional building materials, forms large amounts of ettringite and gypsum dihydrate, causing severe volume expansion in hardened products and resulting in hazards. This invention proposes a method using circulating fluidized bed boiler ash as raw material. By controlling the reaction rate and degree of various chemical reactions, the active calcium source in the ash can be precisely controlled to react with CO2, as well as the degree of gypsum hydration. This allows for the scientific and quantitative control of the effective active calcium and gypsum dihydrate content in the ash that can participate in the expansion reaction, thereby inhibiting the expansion reaction characteristics of the ash.

[0004] Furthermore, compared with existing carbonization methods that utilize solid waste to absorb CO2, such as the Chinese patent application "A method for preparing a rapid lightweight carbonization prefabricated structure of mixed engineering waste soil and a method for strength estimation" (CN120247507A) and the Chinese patent "A method for fixing carbon dioxide using calcium-based solid waste and its application" (CN116199527A), this invention has significant advantages in terms of carbonization rate per unit mass of solid waste, carbonization treatment cost, and utilization channels of carbonized products.

[0005] Furthermore, on the one hand, there are differences in understanding among those skilled in the art; on the other hand, the inventors studied a large number of documents and patents when making this invention, but due to space limitations, not all details and contents were listed in detail. However, this does not mean that the present invention does not possess the features of these prior art. On the contrary, the present invention already possesses all the features of the prior art, and the applicant reserves the right to add relevant prior art to the background art. Summary of the Invention

[0006] This invention relates to a control method for a circulating fluidized bed boiler, and more particularly to a method and system for promoting rapid carbonization of ash and slag in a circulating fluidized bed boiler.

[0007] One objective of this invention is to provide a method for promoting rapid carbonization of ash and slag in circulating fluidized bed boilers, comprising the following steps: S1 circulating fluidized bed boiler ash and water are mixed at a mass ratio of 10:0.5~2 and stirred evenly to obtain a mixture; S2 introduces a gas containing carbon dioxide, maintaining the temperature between 20-160℃ to carry out carbonization. The formula for calculating the gas flow rate participating in the carbonization reaction is shown below:

[0008] Where A is the gas flow rate, in meters per second (m³). 3 / h; m represents the hourly ash and slag processing capacity, in t / h. The effective calcium oxide content per ton of ash residue, expressed in t / t; This represents the volume fraction of CO2 in a gas, expressed in cubic meters (m³). 3 / m 3 Effective calcium oxide refers to the calcium oxide in the ash and slag of circulating fluidized bed boilers as detected according to JC / T 478.2. During the S3 carbonization process, the carbonization degree is increased by adjusting the ratio of the thickness of the stationary layer to the thickness of the moving layer of the mixture, i.e., reducing the thickness of the stationary layer and increasing the thickness of the moving layer.

[0009] According to a preferred embodiment, the ratio of the thickness of the stationary layer to the thickness of the moving layer is in the range of 1:3 to 3:1.

[0010] According to a preferred embodiment, the formula for calculating the mass of CO2 that can be mineralized per ton of ash residue is as follows:

[0011] Where M represents the mass of CO2 required for carbonization of one ton of circulating fluidized bed boiler ash, in tons; This indicates the effective calcium oxide content per ton of circulating fluidized bed boiler ash, expressed in tons (t).

[0012] According to a preferred embodiment, in S1, the bulk density of the mixture is 0.3~1.0 g / cm³. 3 between.

[0013] One objective of this invention is to provide a system for promoting rapid carbonization of ash and slag in a circulating fluidized bed boiler. This system includes a carbonization reaction device, a detection unit, and a control center communicatively connected to the carbonization reaction device. The carbonization reaction device is rotatable and has an inlet for supplying carbon dioxide-containing gas to the carbonization reaction and an exhaust outlet for venting the gas. The control center is configured as follows: Before the carbonization device is turned on, based on the hourly processing capacity of solid waste and the effective calcium oxide content per ton of ash residue, the flow rate of carbon dioxide-containing gas from the inlet is determined according to S2. Based on the real-time monitoring of the thickness of the stationary layer and the thickness of the moving layer of the mixture by the detection unit, and in conjunction with the internal physical structure of the carbonization reaction device, the ratio of the thickness of the stationary layer to the thickness of the moving layer of the mixture can be adjusted by adjusting the tilt angle and rotation speed of the carbonization reaction device.

[0014] According to a preferred embodiment, before aeration is introduced into the reaction space of the carbonization reactor, the circulating fluidized bed boiler ash and water are mixed evenly in a mass ratio of 10:0.5~2 through the carbonization reactor.

[0015] According to a preferred embodiment, the carbonization reaction apparatus is provided with a reaction vessel and a drive unit for driving the reaction vessel to rotate.

[0016] According to a preferred embodiment, 2 to 12 lifting plates are axially installed on the inner wall of the reaction vessel. The lifting plates are oriented towards the axis of the reaction vessel and are flat metal plates.

[0017] According to a preferred embodiment, the height of the feeding plate should not exceed 1 / 5 of the inner wall diameter of the carbonization reactor.

[0018] According to a preferred embodiment, the angle of the feeding plate is 15°~80°.

[0019] The beneficial effects of this invention are: This invention controls the carbonization reaction by using a linkage parameter that controls the gas flow rate, carbonization temperature, and the ratio of the thickness of the stationary layer to the moving layer in the mixture.

[0020] First, a core formula directly and quantitatively links the gas flow rate to the content of the key active ingredient (effective calcium oxide) in the feed, the real-time processing capacity, and the gas source concentration. This ensures that the supplied CO2 quantity maintains an optimal ratio with the amount of carbonizable components in the ash, thereby fundamentally avoiding gas waste, maximizing the carbonization reaction rate and gas utilization, and reducing operating costs.

[0021] Furthermore, unlike traditional approaches that focus solely on chemical composition, this invention discovers that changes in the physical morphology of the mixture during rotational motion significantly impact the carbonization effect (refer to Experimental Examples 1-5). By precisely designing the physical structure of the material-lifting plates within the carbonization reactor and accurately matching the reactor's tilt angle and rotational speed, the number and amplitude of self-circulating micro-regions within the moving layer are increased, thereby increasing the porosity of the moving layer and facilitating the carbonization reaction. Simultaneously, friction between the stationary and moving layers is reduced, thus decreasing the thickness of the stationary layer and enhancing the degree of carbonization. This allows for precise control of the ratio of stationary to moving layer thicknesses in the mixture. Under the same chemical composition conditions, the method of this invention can achieve faster carbonization reactions and higher degrees of carbonization.

[0022] In summary, this invention, through the dual innovation of quantitative gas control and structured material movement design, not only significantly improves the efficiency and economy of the carbonization process, but also achieves proactive and precise control over the quality and performance of carbonization products, thus possessing significant industrial application value. Attached Figure Description

[0023] Figure 1 This is a schematic diagram simulating the motion of the mixture, including the motion states of the mixture in reaction slip, sliding, and throwing. Figure 2 This is a schematic diagram of the cross-section of the material lifting plate structure inside the reactor, including the material lifting plate and the angle between it and the stir-frying inclined plate; Figure 3 This is a schematic diagram showing the ratio of the thickness of the stationary layer to the thickness of the moving layer of the mixture in the reactor in Experiment Example 1. The upper diagram shows the minimum thickness of the stationary layer, and the lower diagram shows the maximum thickness of the stationary layer. Figure 4 This is a schematic diagram showing the ratio of the thickness of the stationary layer to the thickness of the moving layer of the mixture in the reactor in Experiment Example 2. The upper diagram shows the minimum thickness of the stationary layer, and the lower diagram shows the maximum thickness of the stationary layer. Figure 5 This is a schematic diagram showing the ratio of the thickness of the stationary layer to the thickness of the moving layer of the mixture in the reactor in Experiment Example 3. The upper diagram shows the minimum thickness of the stationary layer, and the lower diagram shows the maximum thickness of the stationary layer. Figure 6 This is a schematic diagram showing the ratio of the thickness of the stationary layer to the thickness of the moving layer of the mixture in the reactor in Experiment Example 4. The upper diagram shows the minimum thickness of the stationary layer, and the lower diagram shows the maximum thickness of the stationary layer. Figure 7 This is a schematic diagram showing the ratio of the thickness of the stationary layer to the thickness of the moving layer in the reactor for the mixture in Experiment Example 5. The upper diagram shows the minimum thickness of the stationary layer, and the lower diagram shows the maximum thickness of the stationary layer.

[0024] Figure Labels 100: Feeding plate; 200: Reactor inner wall. Detailed Implementation

[0025] In the description of this invention, terminology is used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly defined.

[0026] Unless otherwise specified, the experimental methods used in the following examples are all conventional methods; the materials, reagents or instruments used, unless otherwise specified by the manufacturer, are all commercially available reagents and materials; the conditions not specified in the examples are all carried out according to conventional conditions or conditions recommended by the manufacturer. At the same time, the present invention does not limit the source of the raw materials used. Unless otherwise specified, the raw materials used in the present invention are all commercially available products in this technical field.

[0027] It should be noted that the height or number of the feeding plates 100 in the following embodiments should be installed, disassembled or adjusted after the equipment has stopped running.

[0028] Example 1 This embodiment relates to a method for promoting rapid carbonization of ash and slag in circulating fluidized bed boilers.

[0029] Step 1: Preparations before processing Collecting circulating fluidized bed boiler ash and slag refers to the solid waste collected from flue gas and furnace bottom during the combustion process of circulating fluidized bed boilers, including circulating fluidized bed ash and circulating fluidized bed slag.

[0030] When preparing process water, tap water or recycled water can be used, but it must be ensured that the chloride ion content in the water is less than 1% to avoid adverse effects on the reaction.

[0031] Meanwhile, according to the standard recorded in "Test Methods for Building Lime Part 2: Chemical Analysis Methods" (JC / T478.2-2013), the effective calcium oxide content in the ash residue was detected. This data is the basis for calculating the subsequent carbonization reaction. Specifically, the calculation formula (1) is as follows: …(1) Where M represents the mass of CO2 required for carbonization of one ton of circulating fluidized bed boiler ash, in tons; This indicates the effective calcium oxide content per ton of circulating fluidized bed boiler ash, expressed in tons (t).

[0032] The amount of gas required for the carbonization reaction is specifically calculated according to formula (2): …(2) Where A is the gas flow rate, in meters per second (m³). 3 / h; m represents the hourly ash and slag processing capacity, in t / h. The effective calcium oxide content per ton of ash residue, expressed in t / t; This represents the volume fraction of CO2 in a gas, expressed in cubic meters (m³). 3 / m 3 .

[0033] Step 2: Pretreatment of raw materials The ash and slag from the circulating fluidized bed boiler are mixed with process water at a mass ratio of 10:0.5~2 in a general-purpose mixer to prepare a powdered mixture. During the mixing process, the bulk density of the mixture must be strictly controlled between 0.3~1.0 g / cm³. 3 This ensures that the material has suitable porosity and reaction interface, creating conditions for efficient carbonization.

[0034] Step 3: Reactive ventilation Prepare a CO2-containing gas as the carbonization reaction gas source, such as boiler flue gas, natural gas boiler flue gas, or other CO2-rich gases.

[0035] Based on the effective calcium oxide content measured in step one, calculate the amount of gas required for the reaction: first, determine the mass of CO2 required for carbonization of each ton of ash residue, which is approximately equal to the effective calcium oxide content (tons) of that ton of ash residue; then, based on the mass content of CO2 in the gas used, calculate the total mass or volume of gas to be introduced.

[0036] The prepared mixture is loaded into the carbonization reaction device, and the CO2-containing gas mentioned above is introduced to start the carbonization reaction.

[0037] The following parameters must be strictly controlled throughout the reaction process: a. The carbonization reaction time is set between 0 and 5 hours; b. The carbonization reaction temperature shall be maintained in the range of 20 to 160°C, and the initial temperature of the introduced gas shall not exceed 200°C; c. Real-time adjustment and control of carbonization reaction gas flow rate, which is calculated based on formula (2).

[0038] Through the precise control described above, rapid and complete carbonization of ash and slag can be achieved.

[0039] Step 4: During rapid carbonization, the degree of carbonization is controlled by adjusting the ratio of the thickness of the stationary layer to the thickness of the moving layer in the mixture. The stationary layer thickness refers to the thickness of the material layer where the mixture remains relatively stationary to the inner wall of the carbonization reactor. The moving layer thickness refers to the thickness of the material layer where there is relative movement between the mixture and the inner wall of the carbonization reactor. For example, the thickness of the material layer where the raw materials can undergo movements such as sliding, slipping, or throwing during the mixing and reaction process.

[0040] The ratio of the thickness of the stationary layer to the thickness of the moving layer in the mixture should be controlled within the range of 1:3 to 3:1.

[0041] The mixture leaving the carbonization reactor is the final carbonized product.

[0042] Example 2 This embodiment relates to a system for promoting rapid carbonization of ash and slag in circulating fluidized bed boilers.

[0043] The system for promoting rapid carbonization of ash and slag in circulating fluidized bed boilers includes a carbonization reaction unit and a control center.

[0044] The rotatable reaction vessel is installed horizontally or at an angle. The reaction vessel is, for example, cylindrical and made of corrosion-resistant and heat-resistant materials. An internal lifting plate 100 is provided; under certain reactor rotation speed conditions, the height and angle of the lifting plate 100 are fixed values. Sealed inlet and outlet ports, as well as gas inlet and outlet ports, are located at both ends of the reaction vessel. The gas inlet is used to introduce CO2-containing gas, and the outlet is connected to a gas treatment or circulation system.

[0045] The drive unit for controlling the rotation of the reaction vessel includes a drive motor, a reducer, and a transmission mechanism (such as gears or pulleys). The drive motor is fixed to the base of the device, and its power is adjusted by the reducer and transmitted to the rolling ring or gear ring on the outer wall of the reaction vessel via the transmission mechanism, driving the vessel to rotate at a set speed at a constant or variable speed.

[0046] The system's control center is an integrated control unit. This control unit can be configured in various forms. Depending on the system's level of automation, data requirements, and deployment environment, it can be one or more of the following: a programmable logic controller (PLC), an industrial computer, an embedded microcontroller, a microprocessor, an edge computing gateway, a cloud server, or a platform. For example, a PLC can directly receive signals from devices such as speed sensors and directly control the start, stop, and speed of the drive motor, executing high-speed, reliable logic control and sequential control. Alternatively, a three-layer IoT architecture integrating a PLC / embedded controller, an edge gateway, and cloud connectivity can be used to combine local real-time control with cloud-based intelligent analysis.

[0047] In this embodiment, by designing 100 lifting plates, adjusting their height and angle, and controlling the tilt angle and rotation speed of the reaction vessel, the ratio of the stationary layer thickness to the moving layer thickness of the mixture is adjusted. Based on relevant experimental research, it has been confirmed that the rotation speed of the reaction vessel is controlled between 2-40 r / min.

[0048] When the ratio of the thickness of the stationary layer to the thickness of the moving layer is less than 1:3, the reactor speed should be reduced to no more than 25 r / min. When the ratio of the thickness of the stationary layer to the thickness of the moving layer is greater than 3:1, the reactor speed should be increased to no less than 8 r / min.

[0049] The operator first sets process parameters such as target rotation speed and reaction time through the control center's interactive interface (e.g., a touchscreen). After startup, the control center sends commands to the drive unit to initiate and adjust the rotation of the reaction vessel. Simultaneously, the rotation speed signal collected in real-time by the detection unit is fed back to the control center. A closed-loop control algorithm (e.g., PID control) dynamically adjusts the motor output to ensure the rotation speed remains precisely and stably within the required range. The entire process achieves automated and precise control of the key dynamic conditions of the carbonization reaction.

[0050] Example 3 The system settings in this embodiment are largely the same as in embodiment 2, except for the adjustment method of the thickness of the stationary layer and the thickness of the moving layer of the mixture.

[0051] The thickness of the stationary layer and the thickness of the moving layer of the mixture can also be achieved by changing the type of the lifting plate 100. The lifting plate 100 is a flat metal plate, which is axially installed on the inner wall of the reaction vessel. Figure 2 The lifting plate 100 should point in the direction of the container cylinder axis, and the height of the lifting plate 100 should not exceed 1 / 5 of the diameter of the inner wall 200 of the carbonization reactor.

[0052] like Figure 2 As shown, the height of the lifting plate 100 should be the distance between the shortest side of the lifting plate cross-section and the inner wall 200 of the reactor.

[0053] As the cylinder of the carbonization reactor rotates, the lifting plate 100 can scoop up the raw material at the bottom. After rotating to a certain height, the raw material will slide down naturally under the action of gravity, but will not form a dilute phase curtain.

[0054] The height of the lifting plate 100 is determined based on the inner diameter of the reactor, and the machine is stopped and adjusted based on the confirmed height of the lifting plate 100.

[0055] When the ratio of the thickness of the stationary layer to the thickness of the moving layer is less than 1:3, the height of the lifting plate 100 is increased until the ratio of the thickness of the stationary layer to the thickness of the moving layer is detected to be between 1:3 and 3:1. When the ratio of the thickness of the stationary layer to the thickness of the moving layer is greater than 3:1, the height of the lifting plate 100 needs to be reduced until the ratio of the thickness of the stationary layer to the thickness of the moving layer is detected to be between 1:3 and 3:1.

[0056] Example 4 The system settings in this embodiment are largely the same as in embodiment 2, except for the adjustment method of the thickness of the stationary layer and the thickness of the moving layer of the mixture.

[0057] like Figure 2 As shown, the angle of the lifting plate 100 is the angle between the extended line of the top of the lifting plate 100 and the inner diameter of the cylinder. The thickness of the stationary layer and the thickness of the moving layer of the mixture can also be achieved by changing the angle of the lifting plate 100.

[0058] The angle of the feeding plate is controlled between 15° and 80°.

[0059] When the ratio of the thickness of the stationary layer to the thickness of the moving layer is less than 1:3, the angle of the lifting plate needs to be reduced by 100 degrees until the ratio of the thickness of the stationary layer to the thickness of the moving layer is detected to be between 1:3 and 3:1; when the ratio of the thickness of the stationary layer to the thickness of the moving layer is greater than 3:1, the angle of the lifting plate needs to be increased by 100 degrees until the ratio of the thickness of the stationary layer to the thickness of the moving layer is detected to be between 1:3 and 3:1.

[0060] Example 5 The thickness of the stationary layer and the moving layer of the mixture can be adjusted by changing the number of lifting plates 100. The number of lifting plates 100 should be controlled between 2 and 12.

[0061] When the ratio of the thickness of the stationary layer to the thickness of the moving layer is less than 1:3, the number of material-lifting plates needs to be reduced by 100 until the ratio of the thickness of the stationary layer to the thickness of the moving layer is detected to be between 1:3 and 3:1; when the ratio of the thickness of the stationary layer to the thickness of the moving layer is greater than 3:1, the number of material-lifting plates needs to be increased by 100 until the ratio of the thickness of the stationary layer to the thickness of the moving layer is detected to be between 1:3 and 3:1.

[0062] Experimental Example 1 Circulating fluidized bed boiler ash with an active calcium oxide content of 10.62% was mixed with water in a mixer at a mass mixing ratio of 10:1 to prepare a powdered mixture.

[0063] The circulating fluidized bed boiler has an ash and slag processing capacity (m) of 0.05 t / h and a bulk density of 0.3 g / cm³. 3 The gas temperature is 160℃, and the CO2 content in the gas mixture is 15%, that is... The value is 15, and the gas flow rate is 0.281 m. 3 / h, the actual CO2 input is 1.57 times the effective calcium oxide content of each ton of circulating fluidized bed boiler ash, the reaction time is 1 h, the number of lifting plates in the carbonization system is 2 out of 100, and the state control of the mixture in the carbonization system is: the ratio of the thickness of the stationary layer material to the thickness of the moving layer material is 2:3~3:1 (e.g., Figure 3 As shown), the height of the feeding plate 100 is 1 / 5D (D is the diameter of the reactor inner wall 200), and the angle is 60°. When carbonization equilibrium is finally reached, the carbonization rate is 58%.

[0064] Experimental Example 2 Circulating fluidized bed boiler ash with an active calcium oxide content of 6.65% was mixed with water in a mixer at a mass mixing ratio of 10:0.5 to prepare a powdered mixture.

[0065] The circulating fluidized bed boiler has an ash and slag processing capacity (m) of 0.01 t / h and a bulk density of 0.5 g / cm³. 3 The gas temperature is 80℃, and the CO2 content in the gas mixture is 12%, that is... The value is 12, and the gas flow rate is 0.105 m. 3 / h, the actual CO2 input is 2.36 times the effective calcium oxide content of each ton of circulating fluidized bed boiler ash, the reaction time is 3 h, the number of lifting plates in the carbonization system is 12 out of 100, and the state control of the mixture in the carbonization system is: the ratio of the thickness of the stationary layer material to the thickness of the moving layer material is 2:3~2:1 (e.g., Figure 4 As shown), the height of the feeding plate 100 is 1 / 10D, and the angle is 15º. When carbonization equilibrium is finally reached, the carbonization rate is 82%.

[0066] Experimental Example 3 Circulating fluidized bed boiler ash with an active calcium oxide content of 7.14% was mixed with water in a mixer at a mass mixing ratio of 10:1.5 to prepare a powdered mixture.

[0067] The circulating fluidized bed boiler has an ash and slag processing capacity (m) of 0.1 t / h and a bulk density of 0.4 g / cm³. 3 The gas temperature is 80℃, and the CO2 content in the flue gas from the coal-fired boiler is approximately 13%, that is... The value is 13, and the gas flow rate is 0.649 m. 3 / h, the actual CO2 input is 1.57 times the effective calcium oxide content of each ton of circulating fluidized bed boiler ash, the reaction time is 3 h, the number of lifting plates in the carbonization system is 4 out of 100, and the state control of the mixture in the carbonization system is: the ratio of the thickness of the stationary layer material to the thickness of the moving layer material is 1:3~3:2 (e.g., Figure 5 As shown in the figure, the height of the feeding plate 100 is 1 / 5D, and the angle is 80º. When carbonization equilibrium is finally reached, the carbonization rate is 62%.

[0068] Test Example 4 Circulating fluidized bed boiler ash with an active calcium oxide content of 4.33% was mixed with water in a mixer at a mass ratio of 10:2 to prepare a powdered mixture. The circulating fluidized bed boiler ash processing capacity (m) was 0.008 t / h, and the bulk density of the mixture was 0.6 g / cm³. 3 The gas temperature is 60℃, and the CO2 content in the natural gas combustion flue gas is 7%, that is... The value is 7, and the gas flow rate is 0.193 m. 3 / h, the actual CO2 input is 3.15 times the effective calcium oxide content of each ton of circulating fluidized bed boiler ash, the reaction time is 4 h, the number of lifting plates in the carbonization system is 6 out of 100, and the state control of the mixture in the carbonization system is: the ratio of the thickness of the stationary layer material to the thickness of the moving layer material is 2:3~3:2 (e.g., Figure 6 As shown in the figure, the height of the feeding plate 100 is 1 / 10D, and the angle is 15º. When carbonization equilibrium is finally reached, the carbonization rate is 94%.

[0069] Experimental Example 5 Circulating fluidized bed boiler ash with an active calcium oxide content of 5.89% was mixed with water in a mixer at a mass ratio of 10:1 to prepare a powdered mixture. The circulating fluidized bed boiler ash processing capacity (m) was 0.1 t / h, and the bulk density of the mixture was 1.0 g / cm³. 3 The gas temperature is 20℃, and the gas is pure CO2 gas, that is... The value is 100, and the gas flow rate is 0.169 m. 3 / h, the actual CO2 input is 3.15 times the effective calcium oxide content of each ton of circulating fluidized bed boiler ash, the reaction time is 5 h, the number of lifting plates in the carbonization system is 10 out of 100, and the state control of the mixture in the carbonization system is: the ratio of the thickness of the stationary layer material to the thickness of the moving layer material is 1:1 to 3:1 (e.g., Figure 6 As shown in the figure, the height of the feeding plate 100 is 1 / 5D, and the angle is 45º. When carbonization equilibrium is finally reached, the carbonization rate is 74%.

[0070] The results of the above experimental examples are illustrated in the figure. Figure 3-7 The horizontal axis represents the angular velocity of the mixture in the carbonization system, and the vertical axis represents the proportion of the mixture. The leftmost bar has the lowest angular velocity; a lower proportion indicates more efficient particle movement by the lifting plates, while a higher proportion reflects greater particle packing or a larger proportion of stationary particles. The ratio of the stationary layer thickness to the moving layer thickness is the sum of the proportions in the leftmost bar and the proportions in the other bars.

[0071] It should be noted that the specific embodiments described above are exemplary, and those skilled in the art can devise various solutions inspired by the disclosure of this invention. These solutions all fall within the scope of this invention and its protection. Those skilled in the art should understand that this specification and its accompanying drawings are illustrative and not intended to limit the scope of the claims. The scope of protection of this invention is defined by the claims and their equivalents.

Claims

1. A method of promoting rapid carbonation of circulating fluidized bed boiler ash, characterized by, Includes the following steps: S1 circulating fluidized bed boiler ash and water are mixed at a mass ratio of 10:0.5~2 and stirred evenly to obtain a mixture; S2 is introduced with a gas containing carbon dioxide, and the temperature is maintained at 20~160℃ to carry out carbonization. The formula for calculating the gas flow rate participating in the carbonization reaction is as follows: Wherein, A is gas flow, unit is m 3 / h; m is ash processing capacity per hour, unit is t / h, is effective calcium oxide content per ton of ash, unit is t / t; is CO2 volume fraction in gas, unit is %; effective calcium oxide refers to calcium oxide in circulating fluidized bed boiler ash detected according to JC / T478.2; During the S3 carbonization process, the carbonization degree is increased by adjusting the ratio of the thickness of the stationary layer to the thickness of the moving layer of the mixture, i.e., reducing the thickness of the stationary layer and increasing the thickness of the moving layer.

2. The method of facilitating rapid carbonation of circulating fluidized bed boiler ash according to claim 1, wherein, The ratio of the thickness of the stationary layer to the thickness of the moving layer is in the range of 1:3 to 3:

1.

3. The method of facilitating rapid carbonation of circulating fluidized bed boiler ash according to claim 1, wherein, The formula for calculating the mass of CO2 that can be mineralized per ton of ash is as follows: Wherein, M represents the mass of CO2 required for carbonization of each ton of circulating fluidized bed boiler ash, in t; M represents the mass of CO2 required for carbonization of each ton of circulating fluidized bed boiler ash, in t.

4. The method of facilitating rapid carbonation of circulating fluidized bed boiler ash according to claim 1, wherein, In S1, the bulk density of the mixture is between 0.3 and 1.0 g / cm 3 .

5. A system for facilitating rapid carbonation of circulating fluidized bed boiler ash according to the method of any one of claims 1 to 4, characterized in that, The system includes a carbonization reaction apparatus, a detection unit, and a control center communicatively connected to the carbonization reaction apparatus. The carbonization reaction apparatus is rotatable and has an inlet for supplying carbon dioxide-containing gas for the carbonization reaction and an exhaust outlet for venting the gas. The control center is configured as follows: Before the carbonization device is started, based on the hourly ash and slag processing capacity of the circulating fluidized bed boiler and the effective calcium oxide content per ton of ash and slag, and according to the flow rate of carbon dioxide-containing gas from the inlet as confirmed by S2, the ratio of the thickness of the stationary layer to the thickness of the moving layer of the mixture is calculated based on the real-time monitoring of the thickness of the stationary layer and the thickness of the moving layer of the mixture by the detection unit. In conjunction with the internal physical structure of the carbonization reaction device, the ratio of the thickness of the stationary layer to the thickness of the moving layer of the mixture is adjusted by adjusting the tilt angle and rotation speed of the carbonization reaction device.

6. The system for facilitating rapid carbonation of ash from a circulating fluidized bed boiler according to claim 5, wherein, Before introducing air into the reaction space of the carbonization reactor, the circulating fluidized bed boiler ash and water are mixed evenly in a mass ratio of 10:0.5~2 through the carbonization reactor.

7. The system for facilitating rapid carbonation of ash from a circulating fluidized bed boiler according to claim 5, wherein, The carbonization reaction apparatus is equipped with a reaction vessel and a drive unit that drives the reaction vessel to rotate.

8. The system for facilitating rapid carbonation of ash from a circulating fluidized bed boiler according to claim 7, wherein, The inner wall of the reaction vessel is axially fitted with 2 to 12 lifting plates.

9. The system for facilitating rapid carbonation of ash from a circulating fluidized bed boiler according to claim 8, wherein, The height of the feeding plate should not exceed 1 / 5 of the diameter of the inner wall (200) of the carbonization reactor.

10. The system for facilitating rapid carbonation of ash from a circulating fluidized bed boiler according to claim 8, wherein, The angle of the feeding plate is 15°~80°.

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