Method for reducing carbon content of slag
By calculating the location of the new slag discharge pipe in the circulating fluidized bed boiler and installing the new slag discharge pipe, the problem of excessive carbon content of the slag is solved, and the carbon content and slag discharge volume of the slag is reduced, and the operation efficiency and safety of the boiler are improved.
Patent Information
- Application Number
- CN202510022166.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-07
- Publication Date
- 2025-04-11
AI Technical Summary
In the circulating fluidized bed boiler, the carbon content of the slag is too high, resulting in increased coal consumption, economic losses and waste of resources, and there are also production safety hazards.
By measuring the distance between the original slag discharge pipe and the coal drop point, the burning time, the single boiling time and displacement of the coal particles, the location of the new slag discharge pipe is calculated, and the original slag discharge pipe is removed and a new slag discharge pipe is installed so that the coal particles can only reach the new slag discharge pipe mouth after boiling and burning in the furnace for many times.
It effectively reduces the carbon content and slag discharge of the slag, ensures the full combustion of coal particles, improves the operating efficiency of the boiler, realizes the full utilization of energy, and improves construction safety.
Smart Images
Figure CN119802586A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of boiler slag removal, and in particular to a method for reducing the carbon content of slag. Background Art
[0002] Circulating fluidized bed boilers use the principle of fluidized bed to fully mix fuel and air, thereby achieving efficient combustion and low emissions and improving fuel utilization efficiency.
[0003] In a circulating fluidized bed boiler, the coal particles fed through the feed pipe burn and release heat in the furnace. After the carbon content in the coal is burned and turned into slag, it is discharged through the slag discharge pipe. In the process of fuel combustion and heat release, the coal particles and slag will be displaced by boiling, and because the slag discharge pipe is usually located in the middle of the furnace, when these particles move in the furnace, some of the incompletely burned coal particles will fall directly into the slag discharge pipe and be discharged together as slag, and cannot be returned to the furnace for combustion. Therefore, this leads to an increase in the carbon content in the slag. Slag with a high carbon content means that the boiler fails to fully utilize the energy of the coal during the combustion process, resulting in an increase in coal consumption, causing certain economic losses and waste of resources. At the same time, due to the high carbon content in the slag, the slag discharge pipe will emit a burning flame when discharging slag, which poses certain production safety risks. Summary of the invention
[0004] In order to solve or partially solve the problems existing in the related art, the present application provides a method for reducing the carbon content of slag, which can be used in a circulating fluidized bed boiler, effectively reduce the carbon content and slag discharge amount of the slag, ensure the safety of production operations, and achieve full utilization of energy.
[0005] The present application provides a method for reducing the carbon content of slag, which is used in a circulating fluidized bed boiler, comprising:
[0006] Measuring the distance between the original slag discharge pipe of the circulating fluidized bed boiler and the coal drop point to obtain a first distance value L1, wherein the coal drop point is calculated according to the height of the feeding pipe and the feeding speed;
[0007] According to the coal particle burnout time t1, the single boiling time t2 and the single boiling displacement m1, the second distance value L2 is calculated, specifically: L2 = m1x (t1 / t2);
[0008] The new slag discharge pipe position is calculated according to the first distance value L1 and the second distance value L2;
[0009] The original slag discharge pipe is removed and a new slag discharge pipe is installed according to the position of the new slag discharge pipe, so that the coal particles can reach the new slag discharge pipe mouth only after multiple boiling and combustion in the furnace, ensuring that the coal particles are fully burned and effectively reducing the carbon content of the slag.
[0010] Optionally, in some embodiments of the present application:
[0011] The coal particle burnout time t1 is set according to the size of the coal particles. When the size of the coal particles is less than 13 mm, the corresponding coal particle burnout time t1 is set to 18 s.
[0012] Optionally, in some embodiments of the present application:
[0013] The single boiling time t2 is set according to the fluidization velocity of the circulating fluidized bed boiler and the single coal particle boiling stroke. When the fluidization velocity of the circulating fluidized bed boiler is 2.35 m / s and the single coal particle boiling stroke is 900 mm, the single boiling time t2 is correspondingly set to 0.38 s.
[0014] Optionally, in some embodiments of the present application:
[0015] The single boiling displacement m1 is set according to the fluidization velocity of the circulating fluidized bed boiler and the single coal particle boiling stroke. When the fluidization velocity of the circulating fluidized bed boiler is 2.35 m / s and the single coal particle boiling stroke is 900 mm, the single boiling displacement m1 is correspondingly set to 18 mm.
[0016] Optionally, in some embodiments of the present application:
[0017] The method of calculating the new slag discharge pipe position according to the first distance value L1 and the second distance value L2 includes:
[0018] A linear coordinate system is established with the original slag discharge pipe as the origin and the direction of coal slag displacement as the positive direction;
[0019] By calculating the difference between the second distance value L2 and the first distance value L1, the coordinate value of the new slag discharge pipe in the linear coordinate system is obtained, and the coordinate value is the position of the new slag discharge pipe.
[0020] Optionally, in some embodiments of the present application:
[0021] The original slag discharge pipe is removed and a new slag discharge pipe is installed according to the position of the new slag discharge pipe, including:
[0022] After removing the original slag discharge pipe, install and connect the water-cooled wall tube at the original slag discharge pipe location.
[0023] Optionally, in some embodiments of the present application:
[0024] The original slag discharge pipe is removed and a new slag discharge pipe is installed according to the position of the new slag discharge pipe, including:
[0025] After dismantling the original slag discharge pipe, arrange an air core pipe and air cap at the original slag discharge pipe position.
[0026] Optionally, in some embodiments of the present application:
[0027] The original slag discharge pipe is removed and a new slag discharge pipe is installed according to the position of the new slag discharge pipe, including:
[0028] At the location of the new slag discharge pipe, modify the water-cooled wall tube to facilitate the installation of the new slag discharge pipe;
[0029] After the new slag discharge pipe is installed, cast the furnace and water-cooled air chamber at the location of the new slag discharge pipe.
[0030] Optionally, in some embodiments of the present application:
[0031] The original slag discharge pipe is removed and a new slag discharge pipe is installed according to the position of the new slag discharge pipe, including:
[0032] After dismantling the original slag discharge pipe, a slag cooler is arranged at the location of the new slag discharge pipe.
[0033] Optionally, in some embodiments of the present application:
[0034] The original slag discharge pipe is removed and a new slag discharge pipe is installed according to the position of the new slag discharge pipe, including:
[0035] After the new slag discharge pipe is installed, connect the slag cooler with the slag discharge pipe, connect the slag cooler with the inlet and outlet water pipes, and connect the slag cooler with the interface of the slag conveying equipment.
[0036] The technical solution provided by this application may have the following beneficial effects:
[0037] The present application removes the original slag discharge pipe and installs a new slag discharge pipe, so that the coal particles can reach the new slag discharge pipe mouth only after multiple boiling and combustion in the furnace, which greatly reduces the probability of coal particles falling directly into the slag discharge pipe, thereby ensuring the full combustion of the coal particles. At the same time, considering the impact of the circulating ash return port returning to the furnace on the operation of the boiler, if the new slag discharge pipe is located close to the circulating ash return port, there is a situation where the circulating ash falls directly into the new slag discharge pipe, affecting the combustion efficiency of the boiler. The position of the new slag discharge pipe set in this embodiment is the shortest position after the coal particles are fully burned, which can effectively prevent the circulating ash from falling directly into the new slag discharge pipe, thereby ensuring the combustion efficiency of the boiler.
[0038] The method of reducing the carbon content of slag in the present application can effectively improve the operating efficiency of the boiler, reduce the carbon content and slag discharge amount of the slag, improve the cooling effect, achieve full utilization of energy, and effectively ensure construction safety.
[0039] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS
[0040] The above and other objects, features and advantages of the present application will become more apparent through a more detailed description of exemplary embodiments of the present application in conjunction with the accompanying drawings, wherein the same reference numerals generally represent the same components in the exemplary embodiments of the present application.
[0041] Figure 1 It is a structural schematic diagram of the method for reducing the carbon content of slag in the present application;
[0042] Figure 2 It is a comparative structural schematic diagram of the circulating fluidized bed boiler after transformation in this application;
[0043] Figure 3 It is a structural diagram of the linear coordinate system in this application. DETAILED DESCRIPTION
[0044] The embodiments of the present application will be described in more detail below with reference to the accompanying drawings. Although the embodiments of the present application are shown in the accompanying drawings, it should be understood that the present application can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided to make the present application more thorough and complete, and to fully convey the scope of the present application to those skilled in the art.
[0045] It should be understood that although the terms "first", "second", "third", etc. may be used in this application to describe various information, this information should not be limited to these terms. These terms are only used to distinguish the same type of information from each other. For example, without departing from the scope of this application, the first information may also be referred to as the second information, and similarly, the second information may also be referred to as the first information. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined.
[0046] In the description of the present application, it should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.
[0047] Unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.
[0048] In a circulating fluidized bed boiler, the coal particles fed through the feed pipe burn and release heat in the furnace. After the carbon content in the coal is burned and turned into slag, it is discharged through the slag discharge pipe. In the process of fuel combustion and heat release, the coal particles and slag will be displaced by boiling, and because the slag discharge pipe is usually located in the middle of the furnace, when these particles move in the furnace, some of the incompletely burned coal particles will fall directly into the slag discharge pipe and be discharged together as slag, and cannot be returned to the furnace for combustion. Therefore, this leads to an increase in the carbon content in the slag. Slag with a high carbon content means that the boiler fails to fully utilize the energy of the coal during the combustion process, resulting in an increase in coal consumption, causing certain economic losses and waste of resources. At the same time, due to the high carbon content in the slag, the slag discharge pipe will emit a burning flame when discharging slag, which poses certain production safety risks.
[0049] In response to the above problems, an embodiment of the present application provides a method for reducing the carbon content of slag, which is used in a circulating fluidized bed boiler and can effectively reduce the carbon content and slag discharge amount of the slag, ensure the safety of production operations, and achieve full utilization of energy.
[0050] The technical solution of the embodiments of the present application is described in detail below with reference to the accompanying drawings.
[0051] Figure 1 It is a structural schematic diagram of the method for reducing the carbon content of slag in the present application;
[0052] Figure 2 It is a comparative structural schematic diagram of the circulating fluidized bed boiler after transformation in this application;
[0053] Figure 3 It is a structural diagram of the linear coordinate system in this application.
[0054] See also Figure 1 , a method for reducing the carbon content of slag, used in a circulating fluidized bed boiler, comprising:
[0055] S100: measuring the distance between the original slag discharge pipe of the circulating fluidized bed boiler and the coal drop point to obtain a first distance value L1, wherein the coal drop point is calculated according to the height of the feeding pipe and the feeding speed.
[0056] In this embodiment, coal particles are transported to the furnace chamber through the feeding structure and the feeding pipe. The coal particles fall in a parabolic motion. Therefore, the height of the feeding pipe is the height of the descent, and the feeding speed is the conveying speed of the feeding structure. The horizontal distance between the coal drop point and the feeding pipe can be accurately calculated, and the first distance value L1 is obtained by calculating the distance between the original slag discharge pipe and the coal drop point. The first distance value L1 represents the horizontal distance between the coal drop point and the original slag discharge pipe. Specifically, for the circulating fluidized bed boiler equipment used in this embodiment, the first distance value L1 is calculated to be 342 mm.
[0057] S200: Calculate the second distance value L2 according to the coal particle burnout time t1, the single boiling time t2 and the single boiling displacement m1, specifically: L2 = m1x(t1 / t2).
[0058] Specifically, the coal particle burnout time t1 is set according to the size of the coal particles. When the size of the coal particles is less than 13 mm, the corresponding coal particle burnout time t1 is set to 18 s.
[0059] In this embodiment, the size of the selected coal particles is specifically 3-10 mm, and the coal particle burnout time t1 is set to 18 s, which can effectively ensure the complete combustion of the coal particles.
[0060] Specifically: the single boiling time t2 is set according to the fluidization velocity of the circulating fluidized bed boiler and the single coal particle boiling stroke. When the fluidization velocity of the circulating fluidized bed boiler is 2.35m / s and the single coal particle boiling stroke is 900mm, the single boiling time t2 is correspondingly set to 0.38s.
[0061] In this embodiment, the single boiling time t2 is calculated by the fluidization velocity of the circulating fluidized bed boiler and the single coal particle boiling stroke, specifically: single boiling time t2 = (fluidization velocity of the circulating fluidized bed boiler) / (single coal particle boiling stroke).
[0062] Specifically, the single boiling displacement m1 is set according to the fluidization velocity of the circulating fluidized bed boiler and the single coal particle boiling stroke. When the fluidization velocity of the circulating fluidized bed boiler is 2.35 m / s and the single coal particle boiling stroke is 900 mm, the single boiling displacement m1 is correspondingly set to 18 mm. The single boiling displacement m1 is obtained through experimental measurement.
[0063] In this embodiment, the number of times the coal particles boil during the burnout period can be calculated by the coal particle burnout time t1 and the single boiling time t2, that is, the number of boiling times = (coal particle burnout time t1) / (single boiling time t2). At the same time, based on the single boiling displacement m1 and the number of boiling times, the displacement distance of the coal particles during the burnout period can be calculated, recorded as the second distance value L2, that is, the second distance value L2 = (single boiling displacement m1) x (boiling times). Integrating the above calculation process, we get: L2 = m1x (t1 / t2). Specifically, in this embodiment, the second distance value L2 = 852.6 mm is calculated.
[0064] S300: Calculate a new slag discharge pipe position according to the first distance value L1 and the second distance value L2.
[0065] Specifically, it includes: establishing a linear coordinate system with the original slag discharge pipe as the origin and the direction of coal slag displacement as the positive direction;
[0066] By calculating the difference between the second distance value L2 and the first distance value L1, the coordinate value of the new slag discharge pipe in the linear coordinate system is obtained, and the coordinate value is the position of the new slag discharge pipe.
[0067] In this embodiment, by establishing a linear coordinate system, L1 is -342mm, the original slag discharge pipe is the origin, and the difference between the second distance value L2 and the first distance value L1 is calculated to be approximately 510mm. For the convenience of modification, a new slag discharge pipe is set at the position coordinate 512mm away from the origin, which is the new slag discharge pipe position.
[0068] S400: The original slag discharge pipe is removed, and a new slag discharge pipe is installed according to the position of the new slag discharge pipe, so that the coal particles can reach the new slag discharge pipe mouth only after multiple boiling and combustion in the furnace, thereby ensuring that the coal particles are fully burned and effectively reducing the carbon content of the slag.
[0069] In this embodiment, the original slag discharge pipe is removed and a new slag discharge pipe is installed, so that the coal particles can reach the new slag discharge pipe mouth only after multiple boiling and combustion in the furnace, so that the probability of coal particles falling directly into the slag discharge pipe is greatly reduced, thereby ensuring the full combustion of the coal particles. At the same time, considering the impact of the circulating ash return port returning to the furnace on the operation of the boiler, if the new slag discharge pipe is located close to the circulating ash return port, there may be a situation where the circulating ash falls directly into the new slag discharge pipe, affecting the combustion efficiency of the boiler. The position of the new slag discharge pipe set in this embodiment is the shortest position after the coal particles are fully burned, which can effectively prevent the circulating ash from falling directly into the new slag discharge pipe, thereby ensuring the combustion efficiency of the boiler.
[0070] Specifically, after the original slag discharge pipe is removed, the water-cooled wall pipe is installed and connected at the original slag discharge pipe position. By installing and connecting the water-cooled wall pipe at the original slag discharge pipe position, the water circulation system of the water-cooled wall pipe is guaranteed to operate normally.
[0071] Specifically, after the original slag discharge pipe is removed, a primary wind core pipe and a wind cap are arranged at the original slag discharge pipe position to ensure the air supply and combustion effect of the boiler.
[0072] Specifically, at the location of the new slag discharge pipe, the water-cooled wall tube is modified to facilitate the installation of the new slag discharge pipe; after the new slag discharge pipe is installed, the furnace and water-cooled air chamber at the location of the new slag discharge pipe are cast. By casting the furnace, the sealing of the connection with the new slag discharge pipe is ensured to avoid heat loss.
[0073] Specifically, after the original slag discharge pipe is removed, a slag cooler is arranged at the position of the new slag discharge pipe.
[0074] Specifically, after the new slag discharge pipe is installed, the slag cooler is connected to the slag discharge pipe, the slag cooler is connected to the inlet and outlet water pipes, and the slag cooler is connected to the interface of the slag conveying equipment.
[0075] By arranging a slag cooler at the location of the new slag discharge pipe and connecting the slag conveying equipment, the slag can be cooled to ensure the safety and efficiency of slag treatment.
[0076] In this embodiment, after the new slag discharge pipe was installed through transformation, during the actual production of the circulating fluidized bed boiler, it was observed that no flame appeared in the new slag discharge pipe. At the same time, the detection showed that the average carbon content of the slag was 2.36%, the carbon content of the slag was greatly reduced, the slag discharge amount decreased by 6.8%, the operating water temperature of the slag cooler decreased by 6 to 9°C, the boiler thermal efficiency increased by 0.66%, and the coal consumption per ton of steam decreased by 1.36 kg.
[0077] The method for reducing the carbon content of slag in the embodiment of the present application can effectively improve the operating efficiency of the boiler, reduce the carbon content and slag discharge amount of the slag, improve the cooling effect, achieve full utilization of energy, and effectively ensure construction safety.
[0078] The technical solution in the embodiment of the present application includes the following beneficial effects:
[0079] The present application removes the original slag discharge pipe and installs a new slag discharge pipe, so that the coal particles can reach the new slag discharge pipe mouth only after multiple boiling and combustion in the furnace, which greatly reduces the probability of coal particles falling directly into the slag discharge pipe, thereby ensuring the full combustion of the coal particles. At the same time, considering the impact of the circulating ash return port returning to the furnace on the operation of the boiler, if the new slag discharge pipe is located close to the circulating ash return port, there is a situation where the circulating ash falls directly into the new slag discharge pipe, affecting the combustion efficiency of the boiler. The position of the new slag discharge pipe set in this embodiment is the shortest position after the coal particles are fully burned, which can effectively prevent the circulating ash from falling directly into the new slag discharge pipe, thereby ensuring the combustion efficiency of the boiler.
[0080] The method of reducing the carbon content of slag in the present application can effectively improve the operating efficiency of the boiler, reduce the carbon content and slag discharge amount of the slag, improve the cooling effect, achieve full utilization of energy, and effectively ensure construction safety.
[0081] Finally, it should be noted that, in this article, relationships such as first and second, etc. are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms include, include or any other variations are intended to cover non-exclusive inclusion, so that a process, method, article or device that includes a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.
[0082] The embodiments of the present application have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The selection of terms used herein is intended to best explain the principles of the embodiments, practical applications, or improvements to the technology in the market, or to enable other persons of ordinary skill in the art to understand the embodiments disclosed herein.
Claims
1. A method for reducing the carbon content of slag, used in a circulating fluidized bed boiler, characterized in that: include: Measuring the distance between the original slag discharge pipe of the circulating fluidized bed boiler and the coal drop point to obtain a first distance value L1, wherein the coal drop point is calculated according to the height of the feeding pipe and the feeding speed; According to the coal particle burnout time t1, the single boiling time t2 and the single boiling displacement m1, the second distance value L2 is calculated, specifically: L2 = m1 x (t1 / t2); The new slag discharge pipe position is calculated according to the first distance value L1 and the second distance value L2; The original slag discharge pipe is removed and a new slag discharge pipe is installed according to the position of the new slag discharge pipe, so that the coal particles can reach the new slag discharge pipe mouth only after multiple boiling and combustion in the furnace, ensuring that the coal particles are fully burned and effectively reducing the carbon content of the slag.
2. The method for reducing the carbon content of slag according to claim 1, characterized in that: The coal particle burnout time t1 is set according to the size of the coal particles. When the size of the coal particles is less than 13 mm, the corresponding coal particle burnout time t1 is set to 18 s.
3. The method for reducing the carbon content of slag according to claim 2, characterized in that: The single boiling time t2 is set according to the fluidization velocity of the circulating fluidized bed boiler and the single coal particle boiling stroke. When the fluidization velocity of the circulating fluidized bed boiler is 2.35 m / s and the single coal particle boiling stroke is 900 mm, the single boiling time t2 is correspondingly set to 0.38 s.
4. The method for reducing the carbon content of slag according to claim 3, characterized in that: The single boiling displacement m1 is set according to the fluidization velocity of the circulating fluidized bed boiler and the single coal particle boiling stroke. When the fluidization velocity of the circulating fluidized bed boiler is 2.35 m / s and the single coal particle boiling stroke is 900 mm, the single boiling displacement m1 is correspondingly set to 18 mm.
5. The method for reducing the carbon content of slag according to claim 4, characterized in that: The calculating of the new slag discharge pipe position according to the first distance value L1 and the second distance value L2 includes: A linear coordinate system is established with the original slag discharge pipe as the origin and the direction of coal slag displacement as the positive direction; the coordinate value of the new slag discharge pipe in the linear coordinate system is obtained by calculating the difference between the second distance value L2 and the first distance value L1, and the coordinate value is the position of the new slag discharge pipe.
6. The method for reducing the carbon content of slag according to any one of claims 1 to 5, characterized in that: The method of removing the original slag discharge pipe and installing a new slag discharge pipe according to the position of the new slag discharge pipe includes: After removing the original slag discharge pipe, install and connect the water-cooled wall tube at the original slag discharge pipe location.
7. The method for reducing the carbon content of slag according to claim 6, characterized in that: The method of removing the original slag discharge pipe and installing a new slag discharge pipe according to the position of the new slag discharge pipe includes: After dismantling the original slag discharge pipe, arrange an air core pipe and air cap at the original slag discharge pipe position.
8. The method for reducing the carbon content of slag according to claim 7, characterized in that: The method of removing the original slag discharge pipe and installing a new slag discharge pipe according to the position of the new slag discharge pipe includes: At the location of the new slag discharge pipe, modify the water-cooled wall tube to facilitate the installation of the new slag discharge pipe; After the new slag discharge pipe is installed, cast the furnace and water-cooled air chamber at the location of the new slag discharge pipe.
9. The method for reducing the carbon content of slag according to claim 8, characterized in that: The method of removing the original slag discharge pipe and installing a new slag discharge pipe according to the position of the new slag discharge pipe includes: After dismantling the original slag discharge pipe, a slag cooler is arranged at the location of the new slag discharge pipe.
10. The method for reducing the carbon content of slag according to claim 9, characterized in that: The method of removing the original slag discharge pipe and installing a new slag discharge pipe according to the position of the new slag discharge pipe includes: After the new slag discharge pipe is installed, connect the slag cooler with the slag discharge pipe, connect the slag cooler with the inlet and outlet water pipes, and connect the slag cooler with the interface of the slag conveying equipment.