Intelligent coal powder screening device, method and system

Abstract

The present application provides an intelligent coal powder screening device, method, and system. In one example, a coal powder particle size detector is used to perform real-time detection of the coal powder particle size after being filtered by a dynamic screening device, determine the proportion of coal powder with a target particle size in the filtered coal powder, and send the target particle size proportion in the filtered coal powder to a controller; a coal powder separation device is used to separate the coal powder that has not passed through the dynamic screen, and the coal powder with a particle size larger than a specified value that has not passed through the dynamic screen is returned to the coal mill for re-grinding, and the remaining coal powder is conveyed to the screen of the dynamic screen for re-filtration, thereby reducing coal waste and improving coal powder screening efficiency; in addition, a coal powder concentration meter is used to measure the concentration of coal powder with a particle size larger than a specified value in the coal powder separation device in real time, and the coal powder concentration is sent to the controller, further improving coal powder filtration efficiency.

Description

Technical Field

[0001] The present application relates to the technical field of pulverized coal processing, and in particular to an intelligent pulverized coal screening device, method and system. Background Art

[0002] In many industrial fields that use pulverized coal, such as electricity and chemical industry, the particle size of pulverized coal has a crucial impact on combustion efficiency and product quality.

[0003] Currently, coal pulverized particle size detection and screening are typically performed as two separate processes. Traditional particle size detection methods often require manual sampling followed by laboratory analysis. This not only fails to reflect the actual particle size of the coal pulverized, but also results in lengthy testing cycles, hindering timely adjustments to production processes. Furthermore, the screening process often uses fixed-size screens, which can lead to inaccurate screening, impacting subsequent production and use. Summary of the Invention

[0004] In view of this, the present application provides an intelligent coal powder screening device, method and system.

[0005] Specifically, this application is implemented through the following technical solutions:

[0006] According to a first aspect of an embodiment of the present application, there is provided an intelligent pulverized coal screening device, comprising:

[0007] A dynamic screening device, comprising at least one dynamic screen, the dynamic screen being arranged obliquely and used for filtering the coal powder obtained after being ground by the coal mill;

[0008] a pulverized coal separation device, disposed corresponding to the at least one dynamic screen, with an inlet of the pulverized coal separation device disposed corresponding to the lower side of the screen surface of the dynamic screen, for receiving pulverized coal entering through the screen surface of the corresponding dynamic screen, and separating the pulverized coal with a particle size larger than a specified value from the remaining pulverized coal, returning the pulverized coal with a particle size larger than the specified value to the coal mill for re-grinding, and re-transporting the remaining pulverized coal to the screen surface of the corresponding dynamic screen;

[0009] a pulverized coal concentration measuring instrument, provided in correspondence with the pulverized coal separation device, for measuring in real time the concentration of pulverized coal with a particle size greater than a specified value in the pulverized coal separation device and transmitting the pulverized coal concentration to a controller; wherein the pulverized coal concentration is used to assist the controller in dynamically adjusting the parameters of the coal mill and / or the dynamic screen;

[0010] The coal powder particle size detector is deployed at a designated position below the powder outlet of the dynamic screening device, and is used to perform real-time detection of the coal powder particle size of the coal powder filtered by the dynamic screening device, determine the proportion of coal powder with a target particle size in the filtered coal powder, and send the proportion of coal powder with a target particle size in the filtered coal powder to the controller; wherein, the proportion of coal powder with a target particle size in the filtered coal powder is used to assist the controller in dynamically adjusting the mill parameters and / or dynamic screen parameters, and the proportion of coal powder with a target particle size in the filtered coal powder is the proportion of coal powder with a particle size exceeding the target particle size in the filtered coal powder.

[0011] According to a second aspect of an embodiment of the present application, an intelligent pulverized coal screening system is provided, comprising: a coal quality rapid detection device, a coal mill, a controller, and the intelligent pulverized coal screening device provided in the first aspect; wherein:

[0012] The coal quality quick detection device is used to detect the coal quality of the coal transported to the coal mill, obtain coal quality information, and send the coal quality information to the controller;

[0013] The controller is configured to determine the expected proportion of target pulverized coal of corresponding target particle size, target coal mill parameters, and target dynamic screen parameters according to the coal quality information, and to set parameters of the coal mill and the dynamic screen according to the target coal mill parameters and the target dynamic screen parameters;

[0014] The controller is further configured to dynamically adjust the coal mill parameters and / or dynamic screen parameters based on the expected proportion of the target particle size coal powder, the coal powder concentration sent by the intelligent coal powder screening device, and the proportion of the target particle size coal powder in the filtered coal powder.

[0015] According to a third aspect of an embodiment of the present application, a smart coal pulverization screening method is provided, which is applied to a controller in a smart coal pulverization screening system. The smart coal pulverization screening system also includes a coal quality rapid detection device, a coal mill, and the smart coal pulverization screening device provided in the first aspect. The method includes:

[0016] receiving the coal quality information sent by the coal quality rapid testing device, determining the corresponding expected proportion of target particle size coal powder, target coal mill parameters, and target dynamic screen parameters according to the coal quality information, and setting parameters of the coal mill and the dynamic screen according to the target coal mill parameters and the target dynamic screen parameters;

[0017] According to the expected proportion of pulverized coal with the target particle size, the pulverized coal concentration sent by the intelligent pulverized coal screening device and the proportion of pulverized coal with the target particle size in the filtered pulverized coal, the coal mill parameters and / or dynamic screen parameters are dynamically adjusted.

[0018] The technical solution provided by this application can at least bring the following beneficial effects:

[0019] By using a dynamic screen to filter the pulverized coal obtained after grinding in the pulverizer, the particle size of the pulverized coal entering the boiler for combustion can be better controlled; in the process of sieving the pulverized coal through the dynamic screen, on the one hand, a pulverized coal particle size detector is used to detect the pulverized coal particle size in real time after being filtered by the dynamic screening device, and the proportion of pulverized coal with a target particle size in the filtered pulverized coal is determined, and the proportion of pulverized coal with a target particle size in the filtered pulverized coal is sent to the controller to assist the controller in dynamically adjusting the pulverizer parameters and / or dynamic screen parameters, so as to better ensure that the particle size of the pulverized coal entering the boiler meets the requirements, thereby improving the combustion efficiency and the stability of the boiler operation; on the other hand, through pulverized coal separation The separation device separates the pulverized coal that has not passed through the dynamic screen, and returns the pulverized coal with a particle size larger than a specified value in the pulverized coal that has not passed through the dynamic screen to the pulverized coal mill for re-grinding, and the remaining pulverized coal is transported to the screen of the dynamic screen for re-filtration, thereby reducing coal waste and improving the pulverized coal screening efficiency; in addition, in the process of separating the pulverized coal that has not passed through the dynamic screen by the pulverized coal separation device, a pulverized coal concentration measuring instrument is used to measure the concentration of the pulverized coal with a particle size larger than a specified value in the pulverized coal separation device in real time, and the pulverized coal concentration is sent to the controller to assist the controller in dynamically adjusting the pulverized coal mill parameters and / or dynamic screen parameters, thereby further improving the pulverized coal filtration efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic structural diagram of an intelligent coal powder screening device shown in an exemplary embodiment of the present application;

[0021] Figure 2 This is a structural diagram of an intelligent coal powder screening system shown in an exemplary embodiment of the present application;

[0022] Figure 3 is a schematic diagram of a main process of coal powder screening shown in an exemplary embodiment of the present application;

[0023] Figure 4 This is a schematic diagram of an implementation of coal mill parameter adjustment shown in an exemplary embodiment of the present application;

[0024] Figure 5A This is a schematic diagram of a coal powder screening process shown in an exemplary embodiment of the present application;

[0025] Figure 5B This is a schematic diagram of a coarse powder separator implementation process shown in an exemplary embodiment of the present application;

[0026] Figure 6 This is a schematic diagram of an industrial computer control process implementation shown in an exemplary embodiment of the present application;

[0027] Figure 7This is a schematic structural diagram of an integrated device for dynamic particle size detection and intelligent screening of coal powder, as shown in an exemplary embodiment of the present application;

[0028] Figure 8 It is a flow chart of an intelligent coal powder screening method shown in an exemplary embodiment of the present application. DETAILED DESCRIPTION

[0029] In order to enable those skilled in the art to better understand the technical solutions provided by the embodiments of the present application, some technical terms involved in the embodiments of the present application are explained below.

[0030] 1. R90: R90 refers to the percentage of particles in the pulverized coal that are larger than a 90-micron sieve. Generally speaking, the lower the R90 value, the finer the pulverized coal.

[0031] 2. R200: R200 refers to the percentage of particles in coal powder that are larger than 200 micron sieve holes.

[0032] 3. Coal mill: a machine that crushes coal blocks and grinds them into coal powder.

[0033] 4. Boiler: An energy conversion device, such as a thermal power plant boiler, used to burn coal to generate electricity.

[0034] 5. DCS (Distributed Control System): Distributed control system.

[0035] In order to make the above-mentioned purposes, features and advantages of the embodiments of the present application more obvious and easy to understand, the technical solutions in the embodiments of the present application are further described in detail below with reference to the accompanying drawings.

[0036] See Figure 1 , is a structural diagram of an intelligent coal powder screening device provided in an embodiment of the present application, such as Figure 1 As shown, the intelligent coal powder screening device may include:

[0037] A dynamic screening device, comprising at least one dynamic screen, the dynamic screen being arranged obliquely and used for filtering the coal powder obtained after being ground by the coal mill;

[0038] a pulverized coal separation device, disposed corresponding to at least one dynamic screen, with an inlet of the pulverized coal separation device disposed corresponding to the lower side of the screen surface of the dynamic screen, for receiving pulverized coal entering through the screen surface of the corresponding dynamic screen, and separating the pulverized coal with a particle size larger than a specified value from the remaining pulverized coal, returning the pulverized coal with a particle size larger than the specified value to the coal mill for re-grinding, and re-transporting the remaining pulverized coal to the screen surface of the corresponding dynamic screen;

[0039] A pulverized coal concentration measuring instrument, provided in correspondence with the pulverized coal separation device, is used to measure in real time the concentration of pulverized coal with a particle size greater than a specified value in the pulverized coal separation device and transmit the pulverized coal concentration to the controller; the pulverized coal concentration is used to assist the controller in dynamically adjusting the parameters of the coal mill and / or the dynamic screen;

[0040] The coal powder particle size detector is deployed at a designated position below the powder outlet of the dynamic screening device, and is used to perform real-time detection of the coal powder particle size of the coal powder filtered by the dynamic screening device, determine the proportion of coal powder with a target particle size in the filtered coal powder, and send the proportion of coal powder with a target particle size in the filtered coal powder to the controller; wherein, the proportion of coal powder with a target particle size in the filtered coal powder is used to assist the controller in dynamically adjusting the mill parameters and / or dynamic screen parameters, and the proportion of coal powder with a target particle size in the filtered coal powder is the proportion of coal powder with a particle size exceeding the target particle size in the filtered coal powder.

[0041] In an embodiment of the present application, in order to control the proportion of coal powder of a specific particle size in the coal ultimately used for combustion, the coal powder obtained after grinding in a coal mill can be filtered through a dynamic screen, and by reasonably setting the sieve hole diameter of the dynamic screen used, the proportion of coal powder of a specific particle size in the coal powder ultimately passing through the dynamic screen can be controlled.

[0042] Taking into account that in actual scenarios, when the coal mill grinds coal to different degrees, the proportion of coal powder of different particle sizes in the coal powder obtained after filtering through the dynamic screen will usually be different. Therefore, in order to ensure that the particle size of the coal powder that finally passes through the dynamic screen meets the specific standards, a coal powder particle size detector can be set below the powder outlet of the dynamic screening device. The coal powder particle size detector can be used to perform real-time detection of the coal powder particle size after filtering the dynamic screening device (the coal powder that finally passes through the dynamic screen) to determine whether the particle size of the filtered coal powder meets the specific standards.

[0043] For example, whether the particle size of the pulverized coal meets a specific standard can be determined by the proportion of pulverized coal with a specific particle size (referred to herein as a target particle size) in the pulverized coal.

[0044] For example, the R90 ratio requirement can be set, that is, the ratio of pulverized coal with a particle size greater than 90 microns in the pulverized coal entering the boiler can be set. Based on this, the ratio of pulverized coal with a particle size greater than 90 microns (taking the target particle size of 90 microns as an example) in the pulverized coal obtained after dynamic sieve filtration can be detected to determine whether the requirement is met.

[0045] For example, the coal powder particle size detector can send the detected proportion of coal powder with a target particle size in the filtered coal powder to the controller to assist the controller in dynamically adjusting the pulverizer parameters and / or dynamic screen parameters. Thus, the controller can dynamically adjust the pulverizer parameters and / or dynamic screen parameters based on the real-time detected proportion of coal powder with a target particle size in the filtered coal powder, so as to better ensure that the particle size of the filtered coal powder meets specific standards and improve the combustion efficiency and the stability of boiler operation.

[0046] In one example, the coal powder particle size detector may include a laser particle size analyzer.

[0047] In the embodiment of the present application, considering that in the process of filtering the coal powder through the dynamic screen, some coal powder with larger particles will be unable to enter the boiler for combustion, in order to reduce waste, the coal powder that fails to pass the screening during the coal powder screening process (which can be called substandard coal powder) can be returned to the pulverizer for re-grinding.

[0048] In addition, considering that in the process of filtering the coal powder through the dynamic screen, the coal powder that does not enter the boiler for combustion usually includes some smaller particles (particle size is smaller than the sieve hole diameter) in addition to the coal powder with larger particles, but the coal powder fails to pass through the screening due to reasons such as being blocked by the large particles of coal powder. For these coal powders, if they are also returned to the pulverizer for re-grinding, the particle size may be too small and the workload of the pulverizer may be increased.

[0049] Based on the above considerations, the coal powder that fails to pass the screening of the dynamic screen can be screened a second time to separate the coal powder with a particle size that does not meet the requirements (such as the particle size is larger than the sieve hole diameter) from the coal powder with a particle size that meets the requirements (such as the particle size is smaller than the sieve hole diameter). The coal powder with a particle size that does not meet the requirements can be returned to the pulverizer for re-grinding, and the coal powder with a particle size that meets the requirements does not need to be returned to the pulverizer, but can be returned to the screen of the dynamic screen and filtered through the dynamic screen again.

[0050] Correspondingly, the intelligent coal powder screening device may also be provided with a coal powder separation device, and the coal powder separation device may be provided corresponding to at least one dynamic screen.

[0051] For example, when a plurality of dynamic screens are provided in the intelligent pulverized coal screening device, a pulverized coal separation device may be provided corresponding to any of the plurality of dynamic screens.

[0052] The dynamic screen in the intelligent coal powder screening device is arranged at an angle, and the entrance of the coal powder separation device can be arranged corresponding to the lower side of the screen surface of the dynamic screen. Therefore, in the process of using the dynamic screen to screen coal powder, the coal powder that does not pass through the screen (coal powder remaining on the screen surface) can slide into the coal powder separation device under the vibration of the screen and the gravity of the coal powder.

[0053] The pulverized coal separation device can be used to separate the pulverized coal with a particle size larger than a specified value (such as the sieve hole diameter of the corresponding screen) from the rest of the pulverized coal, return the pulverized coal with a particle size larger than the specified value to the pulverizer for re-grinding, and re-transport the rest of the pulverized coal to the screen surface of the dynamic screen for re-filtration.

[0054] It should be noted that in the embodiment of the present application, the theoretical goal of the coal powder separation device is to separate the coal powder with a particle size greater than a specified value from the rest of the coal powder. However, in actual applications, the two may not be completely separated. For example, the separated coal powder with a particle size greater than the specified value may be mixed with some coal powder with a particle size smaller than the specified value. That is, the functional description of the above-mentioned coal powder separation device only belongs to the description of the theoretical goal of the coal powder separation device designed in the embodiment of the present application, and is not a limitation on actual usage.

[0055] Furthermore, in the embodiments of the present application, the "specified value of the particle size" in the corresponding descriptions of different pulverized coal separators may be different. For example, the "specified value of the particle size" in the descriptions corresponding to a pulverized coal separator may be the mesh size of the dynamic screen corresponding to the pulverized coal separator.

[0056] In the embodiment of the present application, considering that the grinding degree of the coal mill is insufficient (such as the loading pressure is too small), there will be a large number of large particles of coal powder in the coal powder entering the intelligent coal powder screening device. In this case, even if the large particles of coal powder are returned to the coal mill for re-grinding by reflux, there may still be a large number of large particles of coal powder in the coal powder obtained by re-grinding.

[0057] Based on this, the amount of large-particle coal powder in the coal powder that has not passed the channel screen can also be detected, and the mill parameters can be adjusted based on the amount of large-particle coal powder that has not passed the screen.

[0058] Correspondingly, a coal powder concentration measuring instrument can be provided in the intelligent coal powder screening device corresponding to the coal powder separation device. The coal powder concentration measuring instrument can be used to perform real-time measurement of the concentration of coal powder with a particle size greater than a specified value in the coal powder separation device, and send the coal powder concentration to the controller to assist the controller in dynamically adjusting the mill parameters and / or dynamic screen parameters. Thus, the controller can dynamically adjust the mill parameters and / or dynamic screen parameters based on the real-time detected coal powder concentration to improve the coal powder filtration efficiency.

[0059] In one example, the pulverized coal concentration measuring instrument may include a laser scattering pulverized coal concentration measuring instrument, which can reflect the change value of pulverized coal concentration in real time and efficiently by detecting parameters such as scattered light intensity and angle combined with an algorithm.

[0060] It can be seen that in the intelligent coal powder screening device provided in the embodiment of the present application, the coal powder obtained after grinding in the pulverizer is filtered by using a dynamic screen, so that the particle size of the coal powder entering the boiler for combustion can be better controlled; in the process of screening the coal powder through the dynamic screen, on the one hand, the coal powder particle size detector is used to perform real-time detection of the coal powder particle size of the coal powder filtered by the dynamic screening device, and the proportion of coal powder with a target particle size in the filtered coal powder is determined, and the proportion of coal powder with a target particle size in the filtered coal powder is sent to the controller to assist the controller in dynamically adjusting the coal mill parameters and / or dynamic screen parameters, so as to better ensure that the coal powder particle size entering the boiler meets the requirements, thereby improving the combustion efficiency and the stability of the boiler operation. On the other hand, the pulverized coal that does not pass through the dynamic screen is separated by the pulverized coal separation device, and the pulverized coal with a particle size larger than a specified value in the pulverized coal that does not pass through the dynamic screen is returned to the pulverizer for re-grinding, and the remaining pulverized coal is transported to the screen of the dynamic screen for re-filtration, thereby reducing coal waste and improving the pulverized coal screening efficiency; in addition, in the process of separating the pulverized coal that does not pass through the dynamic screen by the pulverized coal separation device, a pulverized coal concentration measuring instrument is used to measure the concentration of the pulverized coal with a particle size larger than a specified value in the pulverized coal separation device in real time, and the pulverized coal concentration is sent to the controller to assist the controller in dynamically adjusting the pulverized coal parameters and / or the dynamic screen parameters, thereby further improving the pulverized coal filtering efficiency.

[0061] In some embodiments, at least one dynamic screen includes a first dynamic screen and a second dynamic screen, wherein the aperture of the first dynamic screen is larger than the aperture of the second dynamic screen, and the first dynamic screen is deployed above the second dynamic screen; a hollow area with an adjustable area is provided on a higher side of the second dynamic screen;

[0062] The aperture of the second dynamic screen is set according to the target particle size.

[0063] For example, in order to improve the pulverized coal screening efficiency, the at least one dynamic screen in the intelligent pulverized coal screening device may include two dynamic screens (which may be referred to as a first dynamic screen and a second dynamic screen, respectively).

[0064] The mesh size of the first dynamic screen is larger than that of the second dynamic screen, and the first dynamic screen is deployed above the second dynamic screen. Therefore, in the process of filtering the coal powder through the dynamic screen, the coal powder with too large a particle size can be screened out by the first dynamic screen, thereby avoiding the clogging of the mesh size of the second dynamic screen by the coal powder with too large a particle size, which causes the coal powder with a particle size that meets the requirements (such as a particle size smaller than the target particle size) to be unable to pass through the second dynamic screen.

[0065] For example, since a certain proportion of the pulverized coal that eventually enters the boiler for combustion usually requires pulverized coal with a particle size larger than the target particle size, a hollow area with an adjustable area, such as a fan-shaped hollow area, can be set on the higher side of the second dynamic screen. After the pulverized coal is filtered through the first dynamic screen, during the filtration process through the second dynamic screen, the pulverized coal with a particle size smaller than the target particle size can pass through the sieve holes of the second dynamic screen; some pulverized coal with a particle size larger than the target particle size (usually also mixed with pulverized coal with a particle size smaller than the target particle size) can pass through the second dynamic screen from the hollow area.

[0066] For example, by adjusting the area of ​​the hollow region on the second dynamic screen, the proportion of pulverized coal with a target particle size in the pulverized coal passing through the second dynamic screen can be adjusted to a certain extent.

[0067] In some embodiments, the pulverized coal separation device may include:

[0068] The pulverized coal separator comprises a first chamber proximate to a dynamic screen and a second chamber distal to the dynamic screen. The inlet of the first chamber is arranged on the lower side of the screen surface of the dynamic screen, and is configured to receive pulverized coal entering through the screen surface of the dynamic screen. The pulverized coal having a particle size greater than a specified value is separated from the remaining pulverized coal by centrifugal force, and the pulverized coal having a particle size greater than the specified value is separated into the second chamber. The pulverized coal concentration measuring instrument is configured to measure the concentration of the pulverized coal in the second chamber in real time.

[0069] a pulverized coal collection pipe, the inlet of which is connected to the upper side of the first cavity of the pulverized coal separator, and is used to transport the remaining pulverized coal carried up by centrifugal force in the first cavity of the pulverized coal separator back to the screen surface of the corresponding dynamic screen;

[0070] The pulverized coal return pipe has an inlet connected to the second cavity of the pulverized coal separator and is used to return the pulverized coal in the pulverized coal separator with a particle size larger than a specified value to the pulverizer for re-grinding.

[0071] For example, in order to achieve coal powder separation and more accurately determine the concentration of coal powder with a particle size greater than a specified value (which can be called coarse powder) in the coal powder separation process, the coal powder separator in the coal powder separation device can be provided with two cavities (which can be called the first cavity and the second cavity).

[0072] The first cavity is close to the dynamic screen. The coal powder that does not pass through the sieve holes of the dynamic screen can enter the first cavity of the coal powder separator. The coal powder separator uses the centrifugal force principle to separate the coal powder with a particle size greater than the specified value (i.e., coarse powder) and the rest of the coal powder (which can be called fine powder).

[0073] It should be noted that in the embodiments of this application, coarse powder and fine powder are relative terms within the same pulverized coal separator. For any pulverized coal separator, coarse powder can refer to the separated pulverized coal that needs to be returned to the pulverizer for re-grinding; fine powder can refer to the separated pulverized coal that needs to be conveyed to the screen surface of the corresponding dynamic screen. However, for different pulverized coal separators, coarse powder and fine powder cannot directly refer to the size of the pulverized coal particles. For example, if there are multiple pulverized coal separators, the particle size of the coarse powder in one pulverized coal separator can be smaller than the particle size of the fine powder in another pulverized coal separator.

[0074] The upper side of the first cavity can be connected to the inlet of the coal powder collection pipe (also called the fine powder collection pipe). The fine powder separated in the first cavity due to the principle of centrifugal force can be re-transported to the screen surface of the corresponding dynamic screen through the coal powder collection pipe and filtered again by the dynamic screen.

[0075] Compared with the first cavity, the second cavity is farther away from the dynamic screen. The coarse powder separated in the first cavity due to the principle of centrifugal force can enter the second cavity and flow back to the pulverizer for re-grinding through the coal powder return pipe (which can be called the coarse powder return pipe) connected to the second cavity.

[0076] In some embodiments, the intelligent pulverized coal screening device provided in the embodiments of the present application may further include: a feeding device and an air separation device; wherein:

[0077] The feeding device may include:

[0078] A feed pipe connected to the discharge port of the coal mill, used to transport the coal powder obtained after the coal mill is ground into the intelligent coal powder screening device;

[0079] A buffer bin is used to store the pulverized coal entering through the feed pipe; wherein the bottom of the buffer bin can be opened or closed according to a control instruction;

[0080] A material level meter, used for real-time monitoring of the storage amount of pulverized coal in the buffer bin;

[0081] The silo wall vibrator is used to drive the buffer silo wall to vibrate in the working state;

[0082] The air separation device may include:

[0083] An air duct system includes an air inlet duct and an air outlet duct; the air inlet duct is used for external airflow to enter the intelligent coal powder screening device;

[0084] Fan, used to provide wind power for the winnowing process;

[0085] Wind regulating device, used to adjust wind speed and wind temperature;

[0086] A disperser is connected to the air outlet of the air duct system and is used to disperse the coal powder in the buffer bin and drop it to the dynamic screening device.

[0087] For example, to balance the continuous pulverized coal output of the pulverizer and the intermittent demand of boiler combustion, and to avoid unstable combustion due to the start-up and shutdown or failure of the pulverized coal mill, the feeding device of the intelligent pulverized coal screening device can be provided with a buffer bin for storing the pulverized coal entering the intelligent pulverized coal screening device through the feeding pipe.

[0088] It should be noted that in the embodiment of the present application, the intelligent coal powder screening device belongs to a bin body (such as a closed cylinder) from an overall perspective, and a dynamic screening device, a coal powder separation device, a coal powder concentration measuring instrument, a coal powder particle size detector, a feeding device, and an air separation device, etc. can be deployed inside it in the manner described in the above embodiment.

[0089] For example, the device deployed inside the intelligent coal powder screening device can be connected to the outside through a pipeline. For example, the feeding device can be connected to the outside through a feeding pipeline, so that the coal powder obtained after grinding by the pulverizer can enter the intelligent coal powder screening device through the feeding pipeline.

[0090] For another example, the air separation device can be connected to the outside through the air inlet duct, so that the external air flow can enter the intelligent coal powder screening device through the air inlet duct.

[0091] For example, during use of the intelligent pulverized coal screening device, the bottom of the buffer bin may be in an open state at normal conditions, and the bottom of the buffer bin may be controlled to be closed according to demand, so as to control the coal supply to the boiler.

[0092] Since the bottom of the buffer bin is connected to the air separation device, when the bottom of the buffer bin is in an open state, the coal powder entering the intelligent coal powder screening device from the feed pipe will not fall directly to the dynamic screening device, but will form a certain degree of accumulation in the buffer bin due to the obstruction of the air separation device. The falling speed of the coal powder in the buffer bin (the amount of coal powder falling per unit time) can be controlled by cooperating with the bin wall vibrator in the buffer bin and the wind force of the fan in the air separation device.

[0093] When the level meter detects that the amount of pulverized coal stored in the buffer bin exceeds a threshold, the pulverized coal falling speed can be increased, and / or the pulverized coal feeding speed (the amount of pulverized coal entering the buffer bin per unit time) can be reduced.

[0094] The pulverized coal that enters the air separation device through the buffer bin passes through the disperser under the action of wind, and is dispersed and falls to the dynamic screening device, and is filtered according to the method described in the above embodiment.

[0095] See Figure 2, is a structural diagram of an intelligent coal powder screening system provided in an embodiment of the present application, such as Figure 2 As shown, the intelligent coal powder screening system may include: coal quality rapid detection equipment, coal mill, controller, and intelligent coal powder screening device.

[0096] Coal quality rapid testing equipment is used to test the coal quality transported to the coal mill, obtain coal quality information, and send the coal quality information to the controller;

[0097] The controller is used to determine the expected proportion of target pulverized coal with a target particle size, target coal mill parameters, and target dynamic screen parameters according to the coal quality information, and to set parameters for the coal mill and the dynamic screen according to the target coal mill parameters and the target dynamic screen parameters;

[0098] The controller is also used to dynamically adjust the pulverizer parameters and / or dynamic screen parameters based on the expected proportion of target particle size coal powder, the coal powder concentration sent by the intelligent coal powder screening device, and the proportion of target particle size coal powder in the filtered coal powder.

[0099] For example, the structure and function implementation of the intelligent coal powder screening device can refer to the relevant description in the above embodiments.

[0100] In the embodiments of the present application, it is taken into account that the coal of different qualities usually has different pulverized coal particle sizes suitable for boiler combustion. In addition, the coal quality will also affect the pulverizing efficiency of the coal mill and the safety of the equipment. For example, the moisture content of the coal powder will directly affect the heat balance calculation of the coal mill, thereby affecting the drying process of the coal mill and having a significant impact on the safety of the equipment.

[0101] Based on this, in order to improve the pulverizing efficiency and equipment safety of the coal mill and determine a more suitable coal powder particle size, a coal quality quick detection device can be set up in the intelligent coal powder screening system to detect the coal quality of the coal transported to the coal mill and obtain coal quality information.

[0102] For example, coal quality information may include but is not limited to total water, ash, volatile matter, etc.

[0103] For example, the coal quality rapid detection device may send the detected coal quality information to the controller.

[0104] When the controller receives the coal quality information sent by the coal quality rapid testing equipment, it can determine the corresponding expected proportion of target particle size coal powder (i.e., the expected target particle size coal powder proportion), mill parameters (which can be called target mill parameters) and dynamic screen parameters (target dynamic screen parameters) based on the coal quality information, and set the parameters of the mill and dynamic screen based on the expected proportion of target particle size coal powder, the target mill parameters and the target dynamic screen parameters.

[0105] In an embodiment of the present application, in order to better ensure that the proportion of target particle size coal powder in the coal powder filtered through the dynamic screen in the intelligent coal powder screening device can meet the expected proportion, the intelligent coal powder screening device can detect the proportion of target particle size coal powder in the coal powder filtered through the dynamic screen through a coal powder particle size detector (for specific implementation, please refer to the relevant description in the above embodiment), and send the detected proportion of target particle size coal powder in the filtered coal powder to the controller, and the controller dynamically adjusts the pulverizer parameters and / or dynamic screen parameters according to the proportion of target particle size coal powder in the filtered coal powder and the expected proportion.

[0106] In addition, in order to avoid excessive large particles in the coal powder after grinding by the pulverizer, resulting in low coal powder screening efficiency, the intelligent coal powder screening device can also use a coal powder concentration measuring instrument to measure in real time the concentration of coal powder with a particle size greater than a specified value in the coal powder that has not passed through the dynamic screen after filtration (for specific implementation, please refer to the relevant description in the above embodiment), and send the measured coal powder concentration to the controller, which dynamically adjusts the coal mill parameters and / or dynamic screen parameters based on the received coal powder concentration.

[0107] In some embodiments, the controller can be specifically used to dynamically adjust the pulverizer parameters and / or dynamic screen parameters based on a first comparison result of the coal powder concentration and a preset coal powder concentration threshold, and a second comparison result of the proportion of target particle size coal powder in the filtered coal powder and the expected proportion of target particle size coal powder.

[0108] For example, when the controller receives the coal powder concentration sent by the intelligent coal powder screening device, it can compare the received coal powder concentration with a preset coal powder concentration threshold to obtain a corresponding comparison result (which can be referred to as a first comparison result).

[0109] For example, when the controller receives the target particle size coal powder proportion in the filtered coal powder sent by the intelligent coal powder screening device, it can compare the target particle size coal powder proportion in the received filtered coal powder with the expected target particle size coal powder proportion to obtain a corresponding comparison result (which can be called a second comparison result).

[0110] The controller may dynamically adjust the coal mill parameters and / or dynamic screen parameters according to the first comparison result and the second comparison result.

[0111] It should be noted that in the embodiment of the present application, when the intelligent coal powder screening device includes multiple dynamic screens, each dynamic screen will be deployed with a coal powder concentration measuring instrument. Accordingly, the coal powder concentration sent by the intelligent coal powder screening device received by the controller may include the coal powder concentration measured by each coal powder concentration measuring instrument, and the controller may compare the coal powder concentration measured by each coal powder concentration measuring instrument with the corresponding coal powder concentration threshold.

[0112] For example, different pulverized coal concentration measuring instruments may correspond to different pulverized coal concentration thresholds.

[0113] Accordingly, when the intelligent pulverized coal screening device includes a plurality of dynamic screens, the first comparison result may include a comparison result between the pulverized coal concentration measured by each pulverized coal concentration measuring instrument and the corresponding pulverized coal concentration threshold.

[0114] Exemplarily, the controller may determine that the first comparison result is that the coal powder concentration does not exceed the corresponding coal powder concentration threshold when the coal powder concentration measured by each coal powder concentration measuring instrument does not exceed the corresponding coal powder concentration threshold.

[0115] In the case that the pulverized coal concentration measured by any pulverized coal concentration measuring instrument exceeds the corresponding pulverized coal concentration threshold, it can be determined that the first comparison result is that the pulverized coal concentration exceeds the corresponding pulverized coal concentration threshold.

[0116] In one example, the expected proportion of the target particle size coal powder includes an expected proportion range; a hollow area with an adjustable area is provided on a higher side of the lowest dynamic screen in the at least one dynamic screen;

[0117] The controller is specifically configured to increase the loading pressure of the coal mill and / or increase the vibration frequency and amplitude of the corresponding dynamic screen when the first comparison result shows that the coal powder concentration exceeds a preset coal powder concentration threshold and the second comparison result shows that the proportion of coal powder of the target particle size in the filtered coal powder is within an expected proportion range;

[0118] When the first comparison result shows that the pulverized coal concentration does not exceed the preset pulverized coal concentration threshold, and the second comparison result shows that the proportion of pulverized coal of the target particle size in the filtered pulverized coal exceeds the upper limit of the expected proportion range, reducing the area of ​​the hollow region of the lowest dynamic screen;

[0119] If the first comparison result shows that the pulverized coal concentration does not exceed the preset pulverized coal concentration threshold, and the second comparison result shows that the proportion of pulverized coal of the target particle size in the filtered pulverized coal is lower than the lower limit of the expected proportion range, the area of ​​the hollow region of the lowest dynamic screen is increased, and / or the loading pressure of the coal mill is reduced;

[0120] If the first comparison result shows that the pulverized coal concentration exceeds the preset pulverized coal concentration threshold, and the second comparison result shows that the proportion of pulverized coal of the target particle size in the filtered pulverized coal exceeds the upper limit of the expected proportion range, the loading pressure of the coal mill is increased and / or the vibration frequency and amplitude of the corresponding dynamic screen are increased, and the area of ​​the hollow region of the lowest dynamic screen is reduced;

[0121] If the first comparison result shows that the pulverized coal concentration exceeds the preset pulverized coal concentration threshold, and the second comparison result shows that the proportion of pulverized coal of the target particle size in the filtered pulverized coal is lower than the lower limit of the expected proportion range, the loading pressure of the coal mill is increased and / or the vibration frequency and amplitude of the corresponding dynamic screen are increased, and the area of ​​the hollow region of the lowest dynamic screen is increased;

[0122] Among them, in the case where at least one dynamic screen includes multiple dynamic screens, the coal powder concentration exceeds the preset coal powder concentration threshold, including that the coal powder concentration sent by the coal powder concentration measuring instrument corresponding to at least one dynamic screen exceeds the preset coal powder concentration threshold; the coal powder concentration does not exceed the preset coal powder concentration threshold, including that the coal powder concentrations sent by the coal powder concentration measuring instruments corresponding to each dynamic screen do not exceed the preset coal powder concentration threshold.

[0123] For example, the proportion of target particle size coal powder in the filtered coal powder can be used to adjust the area of ​​the hollow region of the lowest dynamic screen in the dynamic screen, and / or to adjust the loading pressure of the coal mill.

[0124] For example, when the proportion of target particle size coal powder in the filtered coal powder exceeds the upper limit of the expected proportion range, the area of ​​the hollow region of the lowest dynamic screen can be reduced, and / or the loading pressure of the coal mill can be increased.

[0125] When the proportion of target particle size coal powder in the filtered coal powder is lower than the lower limit of the expected proportion range, the area of ​​the hollow region of the lowest dynamic screen can be increased, and / or the loading pressure of the coal mill can be reduced.

[0126] The pulverized coal concentration can be used to adjust the vibration frequency and amplitude of the corresponding dynamic screen, and / or to adjust the loading pressure of the coal mill.

[0127] For example, for any dynamic screen, when the coal powder concentration corresponding to the dynamic screen (the coal powder concentration measured by the coal powder concentration measuring instrument set corresponding to the dynamic screen) exceeds the preset concentration threshold, the vibration frequency and amplitude of the dynamic screen can be increased, and / or the loading pressure of the coal mill can be increased.

[0128] Exemplarily, the controller can dynamically adjust the dynamic screen parameters and / or the pulverizer parameters based on the comparison result of the received coal powder concentration and the coal powder concentration threshold (i.e., the above-mentioned first comparison result), and the comparison result of the target particle size coal powder proportion in the received filtered coal powder and the expected proportion range (i.e., the above-mentioned second comparison result).

[0129] For example, when the first comparison result is that the coal powder concentration exceeds the preset coal powder concentration threshold, and the second comparison result is that the proportion of coal powder with a target particle size in the filtered coal powder exceeds the expected proportion range, that is, there are relatively more large-particle coal powder in the coal powder filtered by the corresponding dynamic screen, and the proportion of large-particle coal powder passing through the bottom dynamic screen is also relatively high. In this case, on the one hand, the loading pressure of the pulverizer can be increased, and / or the vibration frequency and amplitude of the corresponding dynamic screen can be increased; on the other hand, the area of ​​the hollow area of ​​the bottom dynamic screen can be reduced.

[0130] In some embodiments, the controller is specifically configured to determine, based on current coal quality information, an expected proportion of pulverized coal of a target particle size corresponding to the current coal quality information using a first model, and to determine, based on the current coal quality information, target mill parameters and target dynamic screen parameters using a second model; wherein the first model is trained using historical training data, the historical training data including historical coal quality information, historical mill parameters, historical proportions of pulverized coal of a target particle size, and historical boiler thermal efficiency;

[0131] The controller is also used to collect corresponding coal quality information, the proportion of target particle size coal powder in the filtered coal powder, coal powder concentration, mill parameters, dynamic screen parameters, and boiler thermal efficiency during the operation of the intelligent coal powder screening system, and train the second model based on the collected data.

[0132] For example, the controller may use the first model to determine the expected proportion of target particle size coal powder corresponding to different coal quality information, and use the second model to determine the coal mill parameters and dynamic screen parameters corresponding to different coal quality information.

[0133] Exemplarily, the first model can be trained based on collected historical training data (which can be referred to as first historical training data).

[0134] For example, the first historical training data may include, but is not limited to, part or all of historical coal quality information, historical coal mill parameters, historical target particle size pulverized coal ratio, and historical boiler thermal efficiency.

[0135] It should be noted that during the operation of the intelligent coal powder screening system, the first model can also be dynamically optimized and trained in real time based on the coal quality information, pulverizer parameters, target particle size coal powder ratio, boiler thermal efficiency and other data collected in real time to improve the accuracy of determining the expected ratio of target particle size coal powder.

[0136] Illustratively, the initial second model can be trained using historical training data (referred to as second historical training data). Illustratively, the second historical training data can include, but is not limited to, some or all of historical coal quality information, the percentage of target particle size pulverized coal in historical filtered pulverized coal, historical pulverized coal concentration, historical pulverized coal mill parameters, historical dynamic screen parameters, and historical boiler thermal efficiency.

[0137] For example, during the operation of the intelligent coal powder screening system, the second model can be dynamically optimized and trained in real time based on the coal quality information collected in real time, the proportion of target particle size coal powder in the filtered coal powder, coal powder concentration, mill parameters, dynamic screen parameters, and boiler thermal efficiency to improve the accuracy of determining the mill parameters and dynamic screen parameters.

[0138] It should be noted that in this embodiment of the present application, the second model may also output an expected percentage of coal dust of a target particle size, and the training of the second model may be verified based on the expected percentage of coal dust of a target particle size output by the first model and the expected percentage of coal dust of a target particle size output by the second model. If the expected percentage of coal dust of a target particle size output by the first model is consistent with the expected percentage of coal dust of a target particle size output by the second model (either identical or with a tolerable error), it can be determined that the second model has entered a stable phase.

[0139] In order to enable those skilled in the art to better understand the technical solutions provided by the embodiments of the present application, the technical solutions provided by the embodiments of the present application are described below with reference to specific examples.

[0140] In this embodiment, taking the target particle size of 90 microns as an example, it is assumed that the intelligent coal powder screening device is provided with two dynamic screens, one screen has a sieve hole diameter of 90 microns, and the other screen has a sieve hole diameter of 200 microns.

[0141] The pulverized coal output from the pulverizer can be dynamically screened and filtered based on the input R90 ratio requirements and the results of coal quality testing to ensure that the particle size of the pulverized coal entering the boiler meets specific standards, thereby improving combustion efficiency and boiler operation stability.

[0142] To achieve the above objectives, this embodiment proposes a solution for dynamic particle size detection and intelligent screening of pulverized coal, which includes at least two parts: one is preliminary coal quality detection; the other is fine screening of pulverized coal.

[0143] After multi-stage crushing, the coal is transported to the pulverizer for grinding via belts or pipelines. In this embodiment, a coal quality rapid testing device can be added to this process to obtain basic coal quality information, such as total water content, ash content, volatile matter, etc. Based on different coal quality information, the appropriate coal powder particle size information (i.e., R90 ratio) is obtained, and the corresponding pulverizer parameters are determined.

[0144] For example, the moisture content of pulverized coal directly affects the heat balance calculation of the coal mill, thereby affecting the drying process of the coal mill and having a significant impact on the safety of the equipment. Traditional laboratory testing takes a long time, and although the test results are instructive for adjustment, they have a strong lag due to the long time consumption. In the embodiments of the present application, by using coal quality rapid testing equipment, coal quality test results can be obtained in a short time, with strong timeliness, and can guide the adjustment of coal mill parameters in real time, thereby enhancing pulverizing efficiency and equipment safety.

[0145] For example, the coal quality rapid inspection equipment detects the coal quality information, and the control equipment (such as an industrial computer) determines the parameters of the coal mill based on the coal quality information and adjusts the parameters of the coal mill; the coal mill grinds the coal according to the adjustment parameters, and the coal powder obtained after grinding is transported to the coal powder fine screening device (i.e., the above-mentioned intelligent coal powder screening device) via a belt or pipeline, and the coal powder is filtered according to the obtained R90 ratio, and the substandard coal powder is collected and returned to the coal mill for re-grinding.

[0146] For example, during the coal powder screening process, the intelligent coal powder screening device can perform coarse powder separation on the coal powder that does not pass through the dynamic mesh screen, and detect the coal powder concentration after the coarse powder separation (the fine powder is re-transported to the coal powder concentration of the coarse powder outside the dynamic mesh screen).

[0147] Among them, the coal powder concentration is high after coarse powder separation, which means that the coal mill grinding is not in place and the coal mill parameters need to be adjusted to increase the degree of coal grinding.

[0148] In addition, the intelligent coal powder screening device can also detect the particle size of the coal powder output after screening in real time. If the particle size is too small (such as the R90 ratio is lower than the preset ratio threshold), it means that the coal mill is over-grinding, and the coal mill parameters need to be adjusted to reduce the degree of coal grinding.

[0149] After filtering, the pulverized coal is transported through pipelines to the pulverized coal bin or boiler for storage or combustion. The flow diagram can be shown as follows: Figure 3 shown.

[0150] For example, a laser particle size analyzer can be set up near the powder outlet of the dynamic screening device to realize the rapid detection of the particle size of the pulverized coal after screening (such as the R90 ratio of the pulverized coal after screening), and the detection results are transmitted to the industrial computer in real time. The industrial computer compares the actual R90 ratio with the expected R90 ratio range. If there is a deviation between the actual R90 ratio and the expected R90 ratio range, the pulverized coal concentration measured by the pulverized coal concentration meter in the pulverized coal reflux mechanism can be combined to make a judgment. For example, when the actual R90 ratio exceeds the upper limit of the expected R90 ratio range, and the pulverized coal concentration measured by the pulverized coal concentration meter at the R200 screen exceeds the preset concentration threshold, it means that the pulverized coal mill is not fully ground. The industrial computer will adjust the pulverized coal mill loading pressure and the separator speed adjustment instructions and send them to the DCS. The DCS will execute the adjustment of the pulverized coal mill parameters to achieve the effect of strengthening grinding and reducing the pulverized coal mill particle size. The schematic diagram can be seen in Figure 4 .

[0151] For example, the pulverizer parameters and actual R90 ratio information can also be recorded to implement reverse training to optimize the pulverizer parameter adjustment algorithm, thereby achieving more precise control of the coal powder particle size and the pulverizer, and achieving the purpose of improving combustion efficiency and boiler operation stability.

[0152] Among them, if the coal powder particle size is too coarse (the actual R90 ratio is too high, such as exceeding the expected upper limit of the R90 ratio), the carbon content of the fly ash will increase, resulting in an increase in the loss of unburned carbon, and at the same time, it may cause the flame center to move upward, the flue gas temperature at the furnace outlet to increase, and reduce the boiler efficiency; if the coal powder particle size is too fine (the actual R90 ratio is too low, such as lower than the expected lower limit of the R90 ratio), it will easily lead to a too fast combustion rate, increase the pulverizing consumption, and at the same time may cause local overheating in the burner area, posing a safety hazard.

[0153] This approach allows the particle size of the incoming coal to be controlled within an appropriate and stable range, thereby maintaining a stable combustion rate, reducing carbon loss, stabilizing boiler temperature and flame height, and enhancing safety. Furthermore, in the case of complete combustion, the generation of incomplete combustion oxides is reduced, lowering pollutant emissions and reducing pollutant treatment costs.

[0154] The following is a brief description of the working process of the intelligent coal powder screening device.

[0155] For example, the coal powder entering the intelligent pulverized coal screening device is evenly dispersed in the device through a disperser. First, it is filtered through the R200 screen. The coal powder with a particle size smaller than the mesh size of the screen (i.e., a particle size less than 200 microns) passes through the screen and moves downward; the unscreened coal powder slides to the coarse powder separator due to the vibration of the screen. The coarse powder separator forms an upward wind through centrifugal force, which brings coal powder with a particle size less than 200 microns into the fine powder collection pipe, and flows back through the fine powder collection pipe into the upper side of the R200 screen for re-filtration; the over-coarse coal powder larger than R200 enters the coarse powder collection pipe, and flows back through the pipe to the coal mill for re-grinding. The same is true for the R90 screen, and its schematic diagram can be seen respectively. Figure 5A and Figure 5B .

[0156] It can be seen that the dynamic screen supports one physical vibration screening, and the coal enters the coarse powder separator for a second air separation screening. The secondary screening supports higher-precision coal powder screening. The second-screened coal powder returns directly to the dynamic screening device, reducing the amount of refluxed coal powder. It also prevents, to a certain extent, the coal powder from being refluxed and ground multiple times due to rough coal powder screening, resulting in a final particle size that is too fine, thereby reducing combustion efficiency. In this embodiment, by combining physical variable frequency vibration screening with air separation screening, the screening accuracy is increased while the loss and reflux of coal powder are reduced. In addition, the coal powder concentration measuring instrument built into the coarse powder separator can also input the detected coal powder concentration into the industrial computer to reversely guide the operation of the coal mill.

[0157] The industrial computer control process is explained below.

[0158] In this embodiment, the industrial computer control component can rely on a coal quality-pulverized coal device adjustment model. First, a coal quality-pulverized coal combustion efficiency model (i.e., the first model) is calculated based on a large amount of coal quality data, coal mill parameters, pulverized coal particle size (e.g., R90 ratio), and historical data on boiler thermal efficiency. This model accepts coal quality information as input and outputs information on the pulverized coal particle size required for efficient combustion (i.e., the expected percentage of pulverized coal at the target particle size). In addition, the coal quality-coal powder device adjustment model (i.e., the second model mentioned above) can be used to determine the mill parameters and dynamic screen parameters based on the coal quality information, and the coal quality-coal powder device adjustment model can be further dynamically optimized and trained based on the media quick detection data, laser particle size analyzer, mill parameters, coarse powder separator detection of coal powder concentration, dynamic screen parameters and boiler thermal efficiency collected during the operation of this device to generate an optimized and trained coal quality-coal powder device adjustment model. This model supports real-time dynamic adjustment of the mill and dynamic screen parameters based on the real-time detection results of coal quality information, realizes real-time high-precision control and management of coal powder particle size based on coal quality, and stabilizes the quality of coal powder flow. Its schematic diagram can be shown as follows Figure 6 shown.

[0159] In addition, the first model and / or the second model can be trained and optimized in reverse based on the data collected during the operation of the device, so that the model accuracy is continuously increased and more intelligent automatic control is achieved.

[0160] The structure and function of the intelligent coal powder screening device are described in detail below with reference to the accompanying drawings.

[0161] See Figure 7 In this embodiment, the structure of the intelligent coal powder screening device can be as follows Figure 7 As shown, it may include:

[0162] 1. Feeding unit.

[0163] 1.1. Feed pipe: It is connected to the discharge port of the coal mill and is made of wear-resistant steel (such as manganese steel). It is an inclined pipe to ensure that the coal powder can smoothly enter the buffer bin.

[0164] 1.2. Flow control valve: Installed on the feed pipeline, the control valve can be started electrically to control the flow of pulverized coal entering the buffer bin by adjusting the valve opening to meet the production needs under different working conditions.

[0165] 1.3. Buffer bin: It is designed in cylindrical shape with a level meter installed on the top to monitor the storage amount of pulverized coal in the bin in real time.

[0166] For example, the capacity of the buffer bin can be determined by the production capacity of the coal mill and the processing capacity of the downstream equipment. For example, the buffer bin can be designed to store 1-2 hours of coal powder production.

[0167] 1.4. Silo wall vibrator: This device consists of a vibration motor and a base. When powered on, the motor vibrates, transmitting the vibrations to the buffer silo wall through the base. This wall vibration reduces friction between the pulverized coal in the buffer silo and the silo wall, destroying internal friction within the pulverized coal and allowing it to resume flow.

[0168] 2. Screening unit.

[0169] 2.1. Dynamic screen:

[0170] 1) R200 sieve: sieve with a pore size of 200 microns.

[0171] For example, the R200 sieve's mesh can be made of high-strength, wear-resistant stainless steel. The frame is driven by a motor, rotating and vibrating around a central axis to achieve uniform filtration. The vibration frequency ranges from 15-30Hz, with an amplitude of 1-3mm, and is controlled by an industrial computer.

[0172] For example, the R200 screen can adopt three-dimensional composite vibration, and the composite vibration trajectory of the xyz axis is an eight-shaped shape.

[0173] 2) R90 sieve: sieve with a pore size of 90 microns.

[0174] For example, the mesh of the R90 screen is made of high-strength, wear-resistant stainless steel, and the frame is driven by a motor and can vibrate.

[0175] For example, there is a fan-shaped hollow area on the screen of the R90 screen, and the hollow fan-shaped area can be controlled by a motor.

[0176] 2.2, air separation device:

[0177] 1) Fan: A centrifugal fan of appropriate power can be selected to provide sufficient wind force for the air separation process.

[0178] For example, the air volume and air pressure of the fan are calculated and selected based on the size of the screening unit and the characteristics of the pulverized coal.

[0179] 2) Air duct system: including air inlet and outlet.

[0180] For example, the air duct can be made of steel plates with smooth inner walls to reduce airflow resistance.

[0181] Exemplarily, an air filter may be installed on the air inlet duct to prevent external impurities from entering the screening unit; the air outlet duct is connected to the disperser.

[0182] 3) Wind force regulating device: By adjusting the opening of the damper and the speed of the fan (which can be controlled by a frequency converter), the wind force and wind temperature can be precisely adjusted to meet the screening requirements of coal powder with different particle sizes.

[0183] 4) Disperser: Installed at the connection between the air duct and the screening unit, it adopts a porous plate or blade structure to evenly distribute the coal powder airflow entering the screening unit, thereby improving the screening effect.

[0184] 3. Separation unit.

[0185] 3.1. Coarse powder separator: Unfiltered coal powder enters the coarse powder separator through the vibration and inclined surface of the screen.

[0186] For example, the coarse powder separator may be a centrifugal separator, so that the coal powder forms a rotating airflow in the separator, and the coarse-particle coal powder is separated under the action of centrifugal force and gravity.

[0187] 3.2. Coarse powder return pipeline: The coarse-particle pulverized coal separated by the coarse powder separator is returned to the pulverizer through this pipeline.

[0188] 3.3. Fine powder collection pipeline: The collection separator separates the fine-sized coal powder, which enters the pipeline with the air flow and is transported back to the fine screening device to achieve fine screening.

[0189] 4. Detection unit.

[0190] 4.1. Pulverized coal concentration measuring instrument: The laser scattering method is used to measure the pulverized coal concentration. By detecting parameters such as scattered light intensity and angle and combining with algorithms, it can reflect the change value of pulverized coal concentration in real time and efficiently, and is used for feedback adjustment of the coal mill and dynamic screen.

[0191] 4.2. Pulverized coal particle size detector: A laser particle size analyzer is used to detect the pulverized coal particle size in real time, and the coal mill is adjusted based on the particle size detection results.

[0192] In this embodiment, an industrial computer can be selected as a controller, which can receive the coal quality information sent by the coal quality rapid detection equipment, determine the expected R90 ratio data (such as the expected R90 ratio range), and compare the R90 ratio data with the R90 ratio data detected by the coal powder particle size detector, and adjust the mill and dynamic screen parameters according to the comparison results.

[0193] For example, the controller may also reversely adjust the parameters of the coal mill and the dynamic screen to optimize the coal powder preparation according to the coal powder concentration data from the coal powder concentration measuring instrument and the R90 ratio data from the coal powder particle size detector.

[0194] See Figure 8 , is a flow chart of an intelligent coal powder screening method provided in an embodiment of the present application, wherein the intelligent coal powder screening method can be applied to the controller in the above embodiment, such as an industrial computer, such as Figure 8 As shown, the intelligent coal powder screening method may include:

[0195] Step S800: Receive coal quality information sent by the coal quality rapid inspection equipment, determine the corresponding target particle size coal powder expected proportion, target mill parameters and target dynamic screen parameters based on the coal quality information, and set the parameters of the mill and dynamic screen based on the target mill parameters and target dynamic screen parameters.

[0196] Step S810: Dynamically adjust the coal mill parameters and / or dynamic screen parameters according to the expected proportion of target particle size coal powder, the coal powder concentration sent by the intelligent coal powder screening device, and the proportion of target particle size coal powder in the filtered coal powder.

[0197] In the embodiments of the present application, it is taken into account that the coal of different qualities usually has different pulverized coal particle sizes suitable for boiler combustion. In addition, the coal quality will also affect the pulverizing efficiency of the coal mill and the safety of the equipment. For example, the moisture content of the coal powder will directly affect the heat balance calculation of the coal mill, thereby affecting the drying process of the coal mill and having a significant impact on the safety of the equipment.

[0198] Based on this, in order to improve the pulverizing efficiency and equipment safety of the coal mill and determine a more suitable coal powder particle size, a coal quality quick detection device can be set up in the intelligent coal powder screening system to detect the coal quality of the coal transported to the coal mill and obtain coal quality information.

[0199] For example, coal quality information may include but is not limited to total water, ash, volatile matter, etc.

[0200] For example, the coal quality rapid detection device may send the detected coal quality information to the controller.

[0201] When the controller receives the coal quality information sent by the coal quality rapid testing equipment, it can determine the corresponding expected proportion of target particle size coal powder (i.e., the expected target particle size coal powder proportion), mill parameters (which can be called target mill parameters) and dynamic screen parameters (target dynamic screen parameters) based on the coal quality information, and set the parameters of the mill and dynamic screen based on the expected proportion of target particle size coal powder, the target mill parameters and the target dynamic screen parameters.

[0202] In an embodiment of the present application, in order to better ensure that the proportion of target particle size coal powder in the coal powder filtered through the dynamic screen in the intelligent coal powder screening device can meet the expected proportion, the intelligent coal powder screening device can detect the proportion of target particle size coal powder in the coal powder filtered through the dynamic screen through a coal powder particle size detector (for specific implementation, please refer to the relevant description in the above embodiment), and send the detected proportion of target particle size coal powder in the filtered coal powder to the controller, and the controller dynamically adjusts the pulverizer parameters and / or dynamic screen parameters according to the proportion of target particle size coal powder in the filtered coal powder and the expected proportion.

[0203] In addition, in order to avoid excessive large particles in the coal powder after grinding by the pulverizer, resulting in low coal powder screening efficiency, the intelligent coal powder screening device can also use a coal powder concentration measuring instrument to measure in real time the concentration of coal powder with a particle size greater than a specified value in the coal powder that has not passed through the dynamic screen after filtration (for specific implementation, please refer to the relevant description in the above embodiment), and send the measured coal powder concentration to the controller, which dynamically adjusts the coal mill parameters and / or dynamic screen parameters based on the received coal powder concentration.

[0204] For example, the specific implementation process of the controller to realize intelligent coal powder screening can be found in the relevant description in the above embodiment, and the embodiment of the present application will not be described in detail here.

Claims

1. An intelligent coal powder screening device, characterized in that: include: A dynamic screening device, comprising at least one dynamic screen, the dynamic screen being arranged obliquely and used for filtering the coal powder obtained after being ground by the coal mill; a pulverized coal separation device, disposed corresponding to the at least one dynamic screen, with an inlet of the pulverized coal separation device disposed corresponding to the lower side of the screen surface of the dynamic screen, for receiving pulverized coal entering through the screen surface of the corresponding dynamic screen, and separating the pulverized coal with a particle size larger than a specified value from the remaining pulverized coal, returning the pulverized coal with a particle size larger than the specified value to the coal mill for re-grinding, and re-transporting the remaining pulverized coal to the screen surface of the corresponding dynamic screen; a pulverized coal concentration measuring instrument, provided in correspondence with the pulverized coal separation device, for measuring in real time the concentration of pulverized coal with a particle size greater than a specified value in the pulverized coal separation device and transmitting the pulverized coal concentration to a controller; wherein the pulverized coal concentration is used to assist the controller in dynamically adjusting the parameters of the coal mill and / or the dynamic screen; The coal powder particle size detector is deployed at a designated position below the powder outlet of the dynamic screening device, and is used to perform real-time detection of the coal powder particle size of the coal powder filtered by the dynamic screening device, determine the proportion of coal powder with a target particle size in the filtered coal powder, and send the proportion of coal powder with a target particle size in the filtered coal powder to the controller; wherein, the proportion of coal powder with a target particle size in the filtered coal powder is used to assist the controller in dynamically adjusting the mill parameters and / or dynamic screen parameters, and the proportion of coal powder with a target particle size in the filtered coal powder is the proportion of coal powder with a particle size exceeding the target particle size in the filtered coal powder.

2. The intelligent coal powder screening device according to claim 1, characterized in that: The at least one dynamic screen includes a first dynamic screen and a second dynamic screen, wherein the aperture of the first dynamic screen is larger than the aperture of the second dynamic screen, and the first dynamic screen is deployed above the second dynamic screen; a hollow area with an adjustable area is provided on a higher side of the second dynamic screen; The aperture of the second dynamic screen is set according to the target particle size.

3. The intelligent pulverized coal screening device according to claim 1, characterized in that: The pulverized coal separation device comprises: A pulverized coal separator comprises a first chamber proximate to the dynamic screen and a second chamber distal to the dynamic screen, wherein the inlet of the first chamber is arranged corresponding to the lower side of the screen surface of the dynamic screen, and is configured to receive pulverized coal entering through the screen surface of the dynamic screen, separate the pulverized coal with a particle size greater than a specified value from the remaining pulverized coal by centrifugal force, and separate the pulverized coal with a particle size greater than the specified value into the second chamber; wherein the pulverized coal concentration measuring instrument is configured to measure the concentration of the pulverized coal in the second chamber in real time; a pulverized coal collection pipe, the inlet of which is connected to the upper side of the first cavity of the pulverized coal separator, and is used to transport the remaining pulverized coal carried up by centrifugal force in the first cavity of the pulverized coal separator back to the screen surface of the corresponding dynamic screen; The coal powder return pipe has an inlet connected to the second cavity of the coal powder separator and is used to return the coal powder in the coal powder separator with a particle size larger than a specified value to the coal mill for re-grinding.

4. The intelligent pulverized coal screening device according to claim 1, characterized in that: Also includes: A feeding device and an air separation device; wherein the feeding device includes: A feed pipe connected to the discharge port of the coal mill, used to transport the coal powder obtained after the coal mill is ground into the intelligent coal powder screening device; A buffer bin is used to store the pulverized coal entering through the feed pipe; wherein the bottom of the buffer bin is opened or closed according to a control instruction; A material level meter, used for real-time monitoring of the storage amount of pulverized coal in the buffer bin; The silo wall vibrator is used to drive the buffer silo wall to vibrate in the working state; The air separation device comprises: An air duct system includes an air inlet duct and an air outlet duct; the air inlet duct is used for external airflow to enter the intelligent coal powder screening device; Fan, used to provide wind power for the winnowing process; Wind regulating device, used to adjust wind speed and wind temperature; A disperser is connected to the air outlet of the air duct system and is used to disperse the coal powder in the buffer bin and drop it to the dynamic screening device.

5. The intelligent pulverized coal screening device according to claim 1, wherein the pulverized coal concentration measuring instrument comprises a pulverized coal concentration measuring instrument using a laser scattering method; and / or The coal powder particle size detector includes a laser particle size analyzer.

6. An intelligent coal powder screening system, characterized in that: include: Coal quality rapid testing equipment, coal mill, controller, and the intelligent coal powder screening device according to any one of claims 1 to 5; wherein: The coal quality quick detection device is used to detect the coal quality of the coal transported to the coal mill, obtain coal quality information, and send the coal quality information to the controller; The controller is configured to determine the expected proportion of target pulverized coal of corresponding target particle size, target coal mill parameters, and target dynamic screen parameters according to the coal quality information, and to set parameters of the coal mill and the dynamic screen according to the target coal mill parameters and the target dynamic screen parameters; The controller is further configured to dynamically adjust the coal mill parameters and / or dynamic screen parameters based on the expected proportion of the target particle size coal powder, the coal powder concentration sent by the intelligent coal powder screening device, and the proportion of the target particle size coal powder in the filtered coal powder.

7. The intelligent pulverized coal screening system according to claim 6, characterized in that: The controller is specifically used to dynamically adjust the pulverizer parameters and / or dynamic screen parameters based on a first comparison result of the coal powder concentration and a preset coal powder concentration threshold, and a second comparison result of the proportion of target particle size coal powder in the filtered coal powder and the expected proportion of target particle size coal powder.

8. The intelligent coal powder screening system according to claim 7, characterized in that: The expected proportion of the target particle size coal powder includes an expected proportion range; a hollow area with an adjustable area is provided on a higher side of the lowest dynamic screen in the at least one dynamic screen; The controller is specifically configured to increase the loading pressure of the coal mill and / or increase the vibration frequency and amplitude of the corresponding dynamic screen when the first comparison result indicates that the pulverized coal concentration exceeds the preset pulverized coal concentration threshold and the second comparison result indicates that the proportion of pulverized coal of the target particle size in the filtered pulverized coal is within the expected proportion range; When the first comparison result is that the pulverized coal concentration does not exceed the preset pulverized coal concentration threshold, and the second comparison result is that the proportion of pulverized coal of the target particle size in the filtered pulverized coal exceeds the upper limit of the expected proportion range, reducing the area of ​​the hollow region of the lowermost dynamic screen; If the first comparison result is that the pulverized coal concentration does not exceed the preset pulverized coal concentration threshold, and the second comparison result is that the proportion of pulverized coal of the target particle size in the filtered pulverized coal is lower than the lower limit of the expected proportion range, increasing the area of ​​the hollow region of the lowermost dynamic screen and / or reducing the loading pressure of the coal mill; If the first comparison result is that the pulverized coal concentration exceeds the preset pulverized coal concentration threshold, and the second comparison result is that the proportion of pulverized coal of the target particle size in the filtered pulverized coal exceeds the upper limit of the expected proportion range, increasing the loading pressure of the coal mill and / or increasing the vibration frequency and amplitude of the corresponding dynamic screen, and reducing the area of ​​the hollow region of the bottommost dynamic screen; If the first comparison result is that the pulverized coal concentration exceeds the preset pulverized coal concentration threshold, and the second comparison result is that the proportion of pulverized coal of the target particle size in the filtered pulverized coal is lower than the lower limit of the expected proportion range, increasing the loading pressure of the coal mill and / or increasing the vibration frequency and amplitude of the corresponding dynamic screen, and increasing the area of ​​the hollow region of the bottommost dynamic screen; Among them, in the case where the at least one dynamic screen includes multiple dynamic screens, the coal powder concentration exceeds the preset coal powder concentration threshold, which includes that the coal powder concentration sent by the coal powder concentration measuring instrument corresponding to at least one dynamic screen exceeds the preset coal powder concentration threshold; the coal powder concentration does not exceed the preset coal powder concentration threshold, which includes that the coal powder concentrations sent by the coal powder concentration measuring instruments corresponding to each dynamic screen do not exceed the preset coal powder concentration threshold.

9. The intelligent pulverized coal screening system according to claim 6, characterized in that: The controller is specifically configured to determine, based on current coal quality information, an expected proportion of pulverized coal of a target particle size corresponding to the current coal quality information using a first model, and to determine, based on the current coal quality information, target mill parameters and target dynamic screen parameters using a pre-trained second model; wherein the first model is trained using first historical training data, the first historical training data including historical coal quality information, historical mill parameters, historical proportions of pulverized coal of a target particle size, and historical boiler thermal efficiency; The controller is also used to collect corresponding coal quality information, the proportion of target particle size coal powder in the filtered coal powder, coal powder concentration, mill parameters, dynamic screen parameters, and boiler thermal efficiency during the operation of the intelligent coal powder screening system, and dynamically optimize the second model based on the collected data; wherein the initial second model is trained using second historical training data, and the second historical training data includes historical coal quality information, the proportion of target particle size coal powder in the historical filtered coal powder, historical coal powder concentration, historical mill parameters, historical dynamic screen parameters, and historical boiler thermal efficiency.

10. An intelligent coal powder screening method, characterized in that: A controller used in an intelligent pulverized coal screening system, wherein the intelligent pulverized coal screening system further includes a coal quality rapid detection device, a coal mill, and the intelligent pulverized coal screening device according to any one of claims 1 to 5, wherein the method comprises: receiving the coal quality information sent by the coal quality rapid testing device, determining the corresponding expected proportion of target particle size coal powder, target coal mill parameters, and target dynamic screen parameters according to the coal quality information, and setting parameters of the coal mill and the dynamic screen according to the target coal mill parameters and the target dynamic screen parameters; According to the expected proportion of pulverized coal with the target particle size, the pulverized coal concentration sent by the intelligent pulverized coal screening device and the proportion of pulverized coal with the target particle size in the filtered pulverized coal, the coal mill parameters and / or dynamic screen parameters are dynamically adjusted.

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