CN116835170A - Raw coal fluidity detection method and device in raw coal bin - Google Patents

Abstract

The application provides a method and a device for detecting raw coal fluidity in a raw coal bin, relates to the technical field of electromagnetic detection, and solves the technical problem that in the prior art, the situation that coal blockage possibly occurs in the raw coal bin is difficult to judge in time. Detecting the flow condition of raw coal in a detection area near an outlet in a raw coal bin; judging whether the detected flow condition is abnormal; if yes, judging whether the blockage removal treatment is needed; if yes, the dredging device is controlled to be started and/or the dredging device is controlled to send out an alarm indication. The application adopts the detection of fluidity to judge the unsmooth and stagnant coal flow of the cross section of the storage bin, finds the problem through detection and analysis, and adopts corresponding measures in time to eliminate the hidden danger of coal breakage, thereby ensuring the stable operation of the unit.

Description

Raw coal fluidity detection method and device in raw coal bin

Technical Field

The application relates to the technical field of electromagnetic detection, in particular to a method and a device for detecting raw coal fluidity in a raw coal bin.

Background

The thermal power plant generally carries out continuous uninterrupted production, and the coal conveying belt generally does not consider 24 hours of continuous operation, so that an intermediate storage device is needed, namely a raw coal bin is quite popular in use, however, the phenomenon of material blockage often occurs in the process of discharging the storage bin, and the normal operation of equipment is seriously influenced. Particularly, in a large-scale thermal power plant provided with a direct-fired pulverizing system, once a raw coal bin is blocked, a unit is forced to drop out force to throw load, or the condition that a large amount of oil is thrown due to unstable boiler combustion occurs, and when the condition is serious, the unit can extinguish the fire, the unit is not scheduled to stop running. Each furnace of a large utility boiler is typically provided with a plurality of raw coal silos, such as six silos, to which the silos are added during belt operation, the storage capacity of each silo being substantially sufficient to correspond to the rated output of the feeder for 12 hours. After each bin is added to the desired level, the belt operation is stopped.

A typical optimized structure of a modern raw coal storage bin is generally cylindrical at the upper part, circular truncated cone at the middle part and hyperbolic cone at the lower part, see fig. 1. The upper opening is large, the lower opening is small, and raw coal falls down by self weight from top to bottom. The falling raw coal flows in the conical coal bin, the area is gradually reduced when the raw coal flows downwards, larger extrusion is formed on the raw coal, the external force and probability of the raw coal sticking to the inner wall of the coal bin are increased, the raw coal flows in the direction from the inner wall of the coal bin to the central coal dropping pipe, and the raw coal does not form large scouring to the inner wall of the coal bin, so that the raw coal fine powder is extremely easy to stick to the inner wall of the coal bin in a natural state, the friction coefficient of the raw coal powder is rapidly increased after the raw coal powder is stuck to the inner wall of the coal bin, the raw coal powder is accumulated layer by layer, and the friction coefficient is increased to cause blockage.

The flow state of the coal in the raw coal bin (such as integral flow, funnel flow and central flow) is not only determined by the half-top angle and the section shrinkage rate of the bin body, but also depends on the coal quality. Under the design condition, the flow of the coal in the raw coal bin is changed into the integral flow, but after the coal quality is changed (the moisture content is increased and the agglomeration property is enhanced after the coal slime is mixed), the flow of the coal in the raw coal bin is changed from the integral flow into a funnel flow state and a central flow state, and the blocking probability of the central flow raw coal bin is much larger than that of the integral flow raw coal bin.

The theory of particle kinematics shows that for dry particles, the bin opening size satisfying no arching is at least 3 times the particle feature size, while wet particles require bin opening size is at least 4 times the particle feature size. Although the bin is designed to take the factors of blockage into consideration as much as possible and prevent the blockage, due to the fact that the raw coal has different impurity content and viscosity, materials are easy to adhere when wet in rainy seasons, materials are easy to freeze in winter, particularly, the agglomeration property of coal is rapidly increased along with the increase of moisture in the coal, the extrusion force of the bin wall on the coal in the downward flowing process in the raw coal bin is increased, loose particles are extruded and agglomerated, and the characteristic size is increased. When the characteristic size of the coal briquette reaches a certain critical value, blockage occurs. In addition, the pollution hardening of the moist coal on the bin wall in the feed opening also makes the feed opening become increasingly narrow, and the blockage probability is increased.

Different coals have different agglomeration. The different agglomeration of coal directly affects the coal blocking condition of the raw coal bin. The moisture of the coal is also an important factor affecting the coal blockage of the raw coal bin, the agglomeration of the coal can be increased by increasing the moisture, and the dynamic repose angle is increased and the fluidity is deteriorated along with the increase of the moisture of the raw coal. In actual production, when the water content (external water content) of the coal reaches 8%, coal blocking and shed blocking phenomena of some unreasonable raw coal bins (rectangular raw coal bins and central flow raw coal bins) begin to appear; when the water content of the coal reaches 10%, the influence of the pressure generated by the dead weight of the raw coal on the sliding of the raw coal particles from top to bottom is increased, the adhesion force among the raw coal particles is increased, the mutual extrusion force of the particles reaches a peak value, the raw coal is easily compacted and adhered on the inner wall of a raw coal hopper, the integral fluidity is poor, and the coal blockage is serious; when the water content of the coal reaches 12%, coal blocking and coal shed frequently occur, and the phenomenon of coal freezing is easy to occur in winter. In particular, under the condition of the existing coal bunker and the moisture of the coal slime, the proportion of the blended coal slime is not more than 30 percent. When the blending ratio is 40% -50%, the times of coal blockage of the coal bunker are multiplied. Besides the continuous operation loosening device, the coal bin is also required to be emptied periodically, so that the safe coal discharging in a short period can be ensured.

Common raw coal bin blockage removing measures include manual blockage removing, bin wall vibrator, air cannon, loosening machine, stainless steel or PU plate lining on the inner bin wall, etc.

The present inventors found that there are at least the following technical problems in the prior art:

at present, whether coal blockage occurs is judged through raw coal flowing out of a raw coal bin, if the amount of the raw coal flowing out of the raw coal bin is reduced, raw coal blockage clearing measures are adopted, and the positions of coal blockage and shed blockage phenomena in the raw coal bin are not determined, so that the blockage clearing efficiency is low; in addition, whether the situation of coal blockage occurs is judged through raw coal flowing out of the raw coal bin, and the judgment mode is that the situation of coal blockage occurs, namely that the situation that the coal blockage possibly occurs in the raw coal bin cannot be timely judged in advance.

Disclosure of Invention

The application aims to provide a method and a device for detecting the fluidity of raw coal in a raw coal bin, which are used for solving the technical problem that the condition that the raw coal bin is likely to be blocked in time is difficult to judge in the prior art _。 The preferred technical solutions of the technical solutions provided by the present application can produce a plurality of technical effects described below.

In order to achieve the above purpose, the present application provides the following technical solutions:

the application provides a raw coal fluidity detection method in a raw coal bin, which comprises the following steps: detecting the flow condition of raw coal in a detection area near an outlet in a raw coal bin; judging whether the detected flow condition is abnormal; if yes, judging whether the blockage removal treatment is needed; if yes, the dredging device is controlled to be started and/or the dredging device is controlled to send out an alarm indication.

Further, detecting the flow condition of raw coal in a detection area near an outlet in a raw coal bin comprises: detecting the flow velocity of raw coal in the area near the outlet in the raw coal bin by adopting a detector; establishing an internal flow state diagram of the raw coal bin according to the detection signal of the detector; wherein the detector can emit and receive electromagnetic waves or acoustic waves.

Further, a detection area is formed in the area 1-3 m above the raw coal bin outlet.

Further, judging whether the blockage removal treatment is needed or not, wherein the blockage removal treatment comprises the following steps of judging whether the coal flow speed reduction is obvious or the coal flow stagnates locally in the raw coal bin; if yes, judging that the blockage removal treatment is needed.

Further, if it is determined that the blockage removal treatment is required: determining a region where the coal flow is obviously slowed down or stagnant; displaying the position of the area needing to be cleared.

Further, the method further comprises the following steps: recording the blocking clearing condition of each area; counting the frequency of clear blockage in each area; and displaying the statistical result.

Further, the method further comprises the following steps: judging whether foreign matters exist in the detection area; if yes, the control sends out an alarm indication.

The present application provides an apparatus comprising: the detection module is used for detecting the flow condition of raw coal in a detection area near an outlet in the raw coal bin; the analysis module is used for judging whether the detected flow condition is abnormal or not and judging whether the analysis needs to carry out blockage removal treatment or not; and the execution module is used for controlling the dredging device to start and/or controlling the dredging device to send out an alarm indication.

The preferred technical scheme of the application at least has the following technical effects: in the downward flowing process of raw coal in the raw coal bin under the action of gravity, coal flow stagnation occurs in individual places due to coal quality characteristics or coal bin structures, so that coal breakage of a coal feeder is caused, and influence and hazard analysis are brought to safe and stable production of a unit. Based on the method, the application provides a raw coal fluidity detection method in a raw coal bin, adopts fluidity detection to judge that the coal flow on the section of the bin is unsmooth, stagnate and the like, finds out the problem through detection and analysis, and timely adopts corresponding measures to eliminate hidden danger of coal breakage, thereby ensuring the stable operation of the unit.

Drawings

In order to more clearly illustrate the embodiments of the application or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described, it being obvious that the drawings in the following description are only some embodiments of the application, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a simplified view of a prior art raw coal silo;

FIG. 2 is a schematic diagram of the appearance of shed coal inside a conventional raw coal bin;

FIG. 3 illustrates a schematic view of a detector disposed on a raw coal bin;

FIG. 4 is a flow chart of a raw coal fluidity detection method in a raw coal bunker provided by the application;

fig. 5 is a control process framework diagram provided by the present application.

In the figure 1, a raw coal bin; 2. a detector; 3. and (3) a cavity.

Detailed Description

In order to make the objects, technical solutions and advantages of the present application more apparent, the technical solutions of the present application will be described in detail below. It will be apparent that the described embodiments are only some, but not all, embodiments of the application. All other embodiments, based on the examples herein, which are within the scope of the application as defined by the claims, will be within the scope of the application as defined by the claims.

Referring to FIG. 5, the application provides a method for detecting raw coal fluidity in a raw coal bin, comprising the following steps of

Detecting the flow condition of raw coal in a detection area near an outlet in a raw coal bin;

judging whether the detected flow condition is abnormal;

if yes, judging whether the blockage removal treatment is needed;

if yes, the dredging device is controlled to be started and/or the dredging device is controlled to send out an alarm indication.

In the downward flowing process of raw coal in the raw coal bin under the action of gravity, coal flow stagnation occurs in individual places due to coal quality characteristics or coal bin structures, so that coal breakage of a coal feeder is caused, and influence and hazard analysis are brought to safe and stable production of a unit. Based on the method, the application provides a raw coal fluidity detection method in a raw coal bin, which is used for judging that the coal flow on the section of the storage bin is unsmooth and stagnated, detecting and analyzing to find the problem, and timely taking corresponding measures to eliminate the hidden danger of coal breakage, thereby ensuring the stable operation of the unit.

The application adopts the detection of fluidity to find the abnormal condition of fluidity of raw coal (materials) in advance, and then adopts effective disposal measures.

After finding out the coal flow stagnation area or the cavity area, the dredging device can be started in time in a targeted manner to act on the area, the conditions of coal flow stagnation, cavity in the bin and the like are eliminated, the coal under the raw coal bin is kept normal, the coal feeding amount meets the requirements, and when the coal flow stagnation or the cavity is eliminated, the dredging device is stopped to operate and is in a standby state. Or adopting manual intervention, namely judging that the blockage removal treatment is needed, controlling to send out an alarm instruction, and manually adjusting the running states of the corresponding coal mill and the corresponding coal feeder in time, if the coal feeder can be stopped for a short time, if the coal breakage is serious, the coal mill can be further stopped, meanwhile, the coal feeder is treated according to the requirement of the running regulations, and after the coal breakage treatment is finished and the coal is normal, the running of the coal pulverizing system can be restored again.

In addition, the application provides a method for detecting the flow condition of raw coal in a raw coal bin, which can also be applied to the detection of the flow condition of materials in other storage tanks.

The method for detecting the flow condition of the raw coal in the detection area near the outlet in the raw coal bin specifically comprises the following steps:

detecting the flow velocity of raw coal in the area near the outlet in the raw coal bin by adopting a detector;

establishing an internal flow state diagram of the raw coal bin according to the detection signal of the detector;

wherein the detector can emit and receive electromagnetic waves or acoustic waves.

Electromagnetic waves or ultrasonic waves have the capacity of penetrating the walls of the metal bin and the walls of the cement reinforced concrete building structures, and a proper detection mode can be selected according to different solid particle materials and bin structures.

The method adopts a detector to detect the flow velocity of raw coal in the area near the outlet in the raw coal bin, namely utilizes electromagnetic waves or ultrasonic waves with a certain specific wavelength to detect the inside of raw coal or solid particle storage devices, such as the raw coal bin, a storage tank and other equipment. Finally, a two-dimensional or three-dimensional flow state diagram in the warehouse is formed by utilizing analysis of transmitted waves and reflected echoes. Electromagnetic wave detection technology and ultrasonic wave detection technology are currently very widely used technology, and are also mature industrial technology, and are not described in detail herein.

In addition, a flow state diagram in the raw coal bin is established according to the detection signal of the detector, and a worker can actively control the dredging device or adopt other corresponding measures through observing the state diagram, so that hidden danger of coal breakage is eliminated, and stable operation of the unit is ensured.

Referring to fig. 3, a detector 2 on a raw coal bin 1 is schematically shown. At least one or two or three detectors are arranged at equal intervals along the circumferential direction of the raw coal bin 1. The detector has both the function of transmitting and receiving echoes (of reflected waves). Of course, the detector can also have a single-shot and single-shot function, at least two detectors are arranged at the moment, and the two detectors are respectively a transmitter and a receiver.

The detector may be stationary, arranged on the bin wall; can also move along the bin wall and be matched with corresponding guide rails. For the movable detector, a datum point is arranged for positioning the movable detector, and the datum point is used for more accurately positioning the abnormal coal flow in the raw coal bin and the position point of the cavity shed coal through positioning the movable detector.

Referring to fig. 4, a control process frame diagram of each device is illustrated.

Judging whether the coal feeder is started or not;

if yes, the detector is controlled to start and continuously operate, and the detector transmits a signal to the controller;

if the coal feeder is judged not to be started, the detector is controlled to be in a deactivated state;

the controller analyzes the signal transmitted by the detector and analyzes and processes the signal;

if the block cleaning treatment is judged, the dredging device is controlled to be started, and if not, the detector continues to work and detect.

The "determination as to whether the blocking removal process is necessary" includes the following:

judging whether obvious coal flow speed reduction or stagnation occurs locally in the raw coal bin;

if yes, judging that the blockage removal treatment is needed.

When the coal flow is in a normal flowing state in the bin, the flow velocity range and the distribution of raw coal flowing out of the raw coal bin are known, and through analysis of echoes, the fact that the flow velocity of solid particle areas in the raw coal bin is obviously reduced or the fluidity of particles in individual areas is greatly different from that of the particles in the normal flowing state can be found, so that the need of blockage removal treatment can be judged, at the moment, a dredging device capable of acting on the areas can be started in a targeted manner in time, the stagnation condition of the coal flow is eliminated, the coal under the raw coal bin is kept normal, and the coal feeding quantity meets the requirements.

The "obvious coal flow deceleration" can be defined by relevant parameters, and is not described in detail herein because the prior art is adopted.

After the coal flow area in the raw coal bin stagnates and expands, a cavity is formed in the raw coal bin, so-called shed coal appears, the cavity formed by the shed coal is likely to be larger, and if the cavity is formed on the section of the whole bin, the smooth coal discharging of coal feeding equipment can be thoroughly influenced. Therefore, when the coal flow stagnates locally in the raw coal bin or the holes locally in the raw coal bin, the need of the blockage removal treatment can be judged, even if blockage removal measures are adopted, the condition of the coal flow stagnate is eliminated, the coal under the raw coal bin is kept normal, and the coal feeding amount meets the requirements.

Preferably, a detection area is formed in an area 1-3 m above the raw coal bin outlet.

In practice, most of the shed coal positions are in the range of 2-3 meters above the shrinkage section of the raw coal bin, namely the outlet of the raw coal bin. The area is scanned by electromagnetic waves or ultrasonic waves with specific wavelength, the speed of coal flow is detected, and the abnormal speed point on the section of the area in the detection range is found in time.

Preferably, if it is determined that the unblocking treatment is required: determining a region where the coal flow is obviously slowed down or stagnant; displaying the position of the area needing to be cleared.

If the specific position and the range of the area needing to be cleaned in the coal bunker can be determined, targeted measures can be taken manually, so that the cleaning efficiency is improved.

Preferably, the method for detecting the fluidity of the raw coal in the raw coal bin further comprises the following steps:

recording the blocking clearing condition of each area;

counting the frequency of clear blockage in each area;

and displaying the statistical result.

Through statistics of the clear blocking area in the raw coal bin, if a certain area in the raw coal bin is highly frequent, the empty bin can be burned for internal inspection at the moment, or some other measures are taken to eliminate the blocking point, so that the fluidity of raw coal particles in the area is improved, and the hidden danger and the defect are thoroughly eliminated.

Preferably, the method for detecting the fluidity of the raw coal in the raw coal bin further comprises the following steps:

judging whether foreign matters exist in the detection area;

if yes, the control sends out an alarm indication.

If metal objects are mixed in solid raw coal particles in the raw coal bin, the raw coal particles and the metal objects have obvious different responses to waves, so that the doped foreign matters in the coal, such as falling lining plates, some metal parts carried along with coal conveying and the like, can be found, the operator is reminded of the running state of the coal mill, and the problems of large vibration and the like of the mill are avoided.

An apparatus, comprising: the detection module is used for detecting the flow condition of raw coal in a detection area near an outlet in the raw coal bin;

the analysis module is used for judging whether the detected flow condition is abnormal or not and judging whether the analysis needs to carry out blockage removal treatment or not;

and the execution module is used for controlling the dredging device to start and/or controlling the dredging device to send out an alarm indication.

The specific manner in which the respective modules perform the operations in the apparatus of the above embodiments have been described in detail in the above embodiments of the related methods, and will not be described in detail herein.

It is to be understood that the same or similar parts in the above embodiments may be referred to each other, and that in some embodiments, the same or similar parts in other embodiments may be referred to.

In the description of the present application, it is to be noted that, unless otherwise indicated, the meaning of "plurality" means two or more; the terms "upper", "lower", "left", "right", "inner", "outer", "front", "rear", "head", "tail", etc., refer to an orientation or positional relationship based on that shown in the drawings, and are merely for convenience in describing the present application and simplifying the description, and do not indicate or imply that the apparatus or elements referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as limiting the present application. Furthermore, the terms "first," "second," "third," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present application, it should also be noted that, unless explicitly specified and limited otherwise, the terms "mounted", "connected" and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected or integrally connected; can be mechanically or electrically connected; can be directly connected or indirectly connected through intermediate coal. The specific meaning of the above terms in the present application can be understood as appropriate by those of ordinary skill in the art.

Any process or method description in a flowchart or otherwise described herein may be understood as: means, segments, or portions of code representing executable instructions including one or more steps for implementing specific logical functions or processes are included in the preferred embodiment of the present application in which functions may be executed out of order from that shown or discussed, including in a substantially simultaneous manner or in an inverse order, depending upon the function involved, as would be understood by those skilled in the art of embodiments of the present application.

It is to be understood that portions of the present application may be implemented in hardware, software, firmware, or a combination thereof. In the above-described embodiments, the various steps or methods may be implemented in software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, may be implemented using any one or combination of the following techniques, as is well known in the art: discrete logic circuits having logic gates for implementing logic functions on data signals, application specific integrated circuits having suitable combinational logic gates, programmable Gate Arrays (PGAs), field Programmable Gate Arrays (FPGAs), and the like.

Those of ordinary skill in the art will appreciate that all or part of the steps carried out in the method of the above-described embodiments may be implemented by a program to instruct related hardware, and the program may be stored in a computer readable storage medium, where the program when executed includes one or a combination of the steps of the method embodiments.

In addition, each functional unit in the embodiments of the present application may be integrated in one processing module, or each unit may exist alone physically, or two or more units may be integrated in one module. The integrated modules may be implemented in hardware or in software functional modules. The integrated modules may also be stored in a computer readable storage medium if implemented as software functional modules and sold or used as a stand-alone product.

The above-mentioned storage medium may be a read-only memory, a magnetic disk or an optical disk, or the like.

In the description of the present specification, a description of the terms "one embodiment," "some embodiments," "examples," "specific examples," or "one example" and the like, means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the application. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiments or examples. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

The foregoing is merely illustrative embodiments of the present application, but the scope of the present application is not limited thereto, and any person skilled in the art can easily think about variations or substitutions within the technical scope of the present application, and the application should be covered. Therefore, the protection scope of the application is subject to the protection scope of the claims.

Claims (8)

1. The method for detecting the fluidity of the raw coal in the raw coal bin is characterized by comprising the following steps of

Detecting the flow condition of raw coal in a detection area near an outlet in a raw coal bin;

judging whether the detected flow condition is abnormal;

if yes, judging whether the blockage removal treatment is needed;

if yes, the dredging device is controlled to be started and/or the dredging device is controlled to send out an alarm indication.

2. The method for detecting the fluidity of raw coal in a raw coal bunker according to claim 1, wherein detecting the flow condition of raw coal in a detection area near an outlet in the raw coal bunker comprises:

detecting the flow velocity of raw coal in the area near the outlet in the raw coal bin by adopting a detector;

establishing an internal flow state diagram of the raw coal bin according to the detection signal of the detector;

wherein the detector can emit and receive electromagnetic waves or acoustic waves.

3. The method for detecting the fluidity of raw coal in a raw coal bunker according to claim 1 or 2, wherein a detection area is formed in a region 1 to 3m above an outlet of the raw coal bunker.

4. The method for detecting the fluidity of raw coal in a raw coal bunker according to claim 1, wherein the method for judging whether the blockage removal treatment is needed comprises the following steps:

judging whether obvious coal flow speed reduction or coal flow stagnation occurs locally in the raw coal bin;

if yes, judging that the blockage removal treatment is needed.

5. The method for detecting the fluidity of raw coal in a raw coal bunker according to claim 4, wherein if it is determined that the blockage removal treatment is required:

determining a region where the coal flow is obviously slowed down or stagnant;

displaying the position of the area needing to be cleared.

6. The method for detecting the fluidity of raw coal in a raw coal bunker according to claim 4, further comprising:

recording the blocking clearing condition of each area;

counting the frequency of clear blockage in each area;

and displaying the statistical result.

7. The method for detecting the fluidity of raw coal in a raw coal bunker according to claim 1, further comprising:

judging whether foreign matters exist in the detection area;

if yes, the control sends out an alarm indication.

8. An apparatus, comprising:

the detection module is used for detecting the flow condition of raw coal in a detection area near an outlet in the raw coal bin;

the analysis module is used for judging whether the detected flow condition is abnormal or not and judging whether the analysis needs to carry out blockage removal treatment or not;

and the execution module is used for controlling the dredging device to start and/or controlling the dredging device to send out an alarm indication.