JP5171757B2 - Piping clogging detection device and piping clogging detecting method - Google Patents

Description

  The present invention relates to a device for detecting clogging of a pipe provided in a charging pipe (chute device) for charging the input into a garbage incinerator, a silo or the like, and a pipe clogging detecting method.

  For example, in a garbage incinerator, if the input pipe that communicates with the main body of the incinerator is clogged with the input material and the supply of dust into the furnace becomes unstable, the combustion state may deteriorate. If the clogging becomes large, the removal work will also be costly. For this reason, early detection of clogging is an important issue. For this reason, various techniques for detecting clogging of the input pipe have been developed.

  For example, Patent Literature 1 discloses a powder clogging detection device for a cyclone chute. This technology pays attention to vibration and sound generated by the collision between solid matter flowing in the pipe and the pipe or in-pipe apparatus, and detects clogging by utilizing the fact that the impact vibration and sound are reduced when clogging occurs. That is, when the vibration / sound is large, there is no clogging, and when the vibration / sound is small, it is determined that “clogging occurs”.

  Patent Document 2 discloses a method for detecting clogging of plastic transportation piping. In this technique, in order to specify the clogging position, vibration / sound sensors are provided at a plurality of locations on the pipe, and the clogging situation is detected from the output of the sensor at each position.

Japanese Patent Laid-Open No. 6-255749 JP 2001-206546 A

However, the detection techniques of Patent Document 1 and Patent Document 2 detect a change in flow caused by a change in the input amount of the input material and a change in vibration caused by a decrease in the bulk specific gravity of the input material as “clogging”. There were many cases where misjudgments were made.
For example, considering a situation in which a small amount of input is continuously input, in this situation, “clogging” does not occur and the situation is normal. However, in the detection techniques of Patent Literature 1 and Patent Literature 2, since the output value from the vibration sensor is small, there is a high possibility of erroneous determination that “clogged” exists. Similarly, the impact vibration (sometimes referred to as collision vibration) is reduced because the input material has changed to a soft and light one, and it may be misjudged as “clogged” even though it flows without clogging. sell.

  In particular, incinerators for garbage from ordinary households, wastes of various sizes and bulk specific gravity are crushed, and the amount to be fed varies depending on the operating conditions. Therefore, accurate detection is difficult with conventional technology. is there. The technique of Patent Document 2 shows a method for responding to changes in the type and amount of the input by changing the frequency range of interest of vibration and sound, but the size of the input is determined to some extent. However, accurate detection is not possible when there are a large number of changes in the type and amount of the input and when it changes frequently, such as in an incinerator for general garbage.

  Therefore, in view of the above problems, an object of the present invention is to provide a detection device that can stably detect clogging of piping regardless of changes in the flow rate and quality of input.

In order to achieve the above-described object, the present invention takes the following technical means.
The pipe clogging detection device of the present invention detects clogging in a pipe into which an input is introduced from above, and a plurality of vibration sensors are attached to the pipe wall of the pipe. When the detected vibration is reduced at different timings, a determination unit is provided that determines that the pipe is clogged.

The pipe clogging detection device of the present invention is suitable when the pipe is an input pipe that inputs the input into a garbage incinerator.
The inventors of the present application have conducted extensive research to develop a detection device that can stably detect clogging of piping regardless of changes in the flow rate and quality of the input, and clogging in piping installed in incinerators and the like. It came to know that the generation mechanism is as follows.

  In an incinerator for trash from ordinary households, crushed received trash is put into an input pipe. In order to prevent equipment troubles, the types and sizes of trash that are accepted are limited, but rarely non-standard trash may be included, and they may be thrown in without being sufficiently crushed. is there. For example, when long stick-shaped garbage or garbage such as a fishing net is thrown in, there is a possibility that the pipe will be clogged by being caught in the pipe. In addition, highly sticky dust may adhere to the piping wall and cause this. For this reason, once the input material adheres to the inner surface of the pipe, as shown in FIG. 2, the input material that is input later stays on the upstream side of the adhering input material, and the adhering material itself becomes larger. Eventually, the deposit on the side wall of the pipe increases from the downstream side to the upstream side, and the pipe itself narrows and eventually closes due to the deposit.

  The present invention detects piping clogging by paying attention to the above-mentioned “attachment process of the input material”, and a plurality of vibration sensors are attached to the pipe wall of the piping. When the input is flowing down normally, relatively regular vibration is detected at a substantially constant level from any of the plurality of vibration sensors. The output level from the vibration sensor close to the kimono is significantly reduced. In addition, since the deposit state of the deposits extends from the downstream side to the upstream side of the pipe, the vibration levels detected by the plurality of vibration sensors decrease at different timings. Therefore, the determination unit determines that the pipe is clogged when vibrations detected by the plurality of vibration sensors are reduced at different timings.

Based on the result of this determination unit, it is possible to reliably detect clogging of piping, and to detect vibration fluctuations caused by changes in the input amount of the input material and changes in the bulk specific gravity of the input material as “clogging”, so that no erroneous determination is made. . As a result, clogging of the pipe can be detected stably regardless of changes in the flow rate and quality of the input.
Preferably, the plurality of vibration sensors are respectively arranged from the upstream side to the downstream side of the pipe, and the determination unit is configured to reduce the vibration when the vibration is reduced from the downstream side to the upstream side of the pipe. It may be determined that the pipe is clogged.

As described above, the adhesion of the input material in the pipe spreads from the downstream side to the upstream side. Therefore, when a plurality of vibration sensors are arranged from the upstream side to the downstream side of the pipe and the vibration from each sensor is reduced sequentially from the downstream side to the upstream side of the pipe, the pipe is clogged. If it is determined that it has occurred, a clogged pipe can be reliably detected.
More preferably, the plurality of vibration sensors may be provided on the side wall of the pipe on the side where the input collides.

By doing so, it becomes possible to reliably detect the vibration caused by the input.
Further, the plurality of vibration sensors are respectively disposed along a circumferential direction of a pipe wall of the pipe, and the determination unit applies to the pipe when vibration is reduced along the circumferential direction of the pipe. It may be determined that clogging has occurred.
In the case of an input pipe arranged vertically, the input charge may collide at any part in the circumferential direction inside the pipe. Therefore, by arranging the plurality of vibration sensors along the circumferential direction of the pipe wall of the pipe, the vibration of the pipe can be reliably detected and the clogged state can be accurately determined.

Furthermore, the piping may be provided with vibration suppressing means for suppressing propagation of vibration through the piping, and the vibration sensor may be provided for each section delimited by the vibration suppressing means.
This vibration suppressing means makes it difficult for vibration generated in the pipe to propagate through the pipe and makes the difference in vibration for each vibration sensor clearer, so that the accuracy of clogging determination can be increased.

In the pipe clogging detection method of the present invention, the vibration of the pipe is detected by a plurality of vibration sensors attached to the pipe wall of the pipe into which the input is introduced from above, and the detected vibration is reduced at different timings. In this case, it is determined that the pipe is clogged.
According to this method, clogging of the pipe can be reliably detected, and it is possible to avoid erroneously determining that the fluctuation in vibration caused by the change in the input amount of the input material or the change in the bulk specific gravity of the input material is “clogged”.

  According to the pipe clogging detection device and the pipe clogging detection method according to the present invention, it is possible to stably detect the clogging situation of the pipe regardless of changes in the flow rate and quality of the input.

It is the schematic of the piping clogging detection apparatus which concerns on 1st Embodiment installed in the incinerator. It is the elements on larger scale of the piping clogging detection apparatus which concerns on 1st Embodiment. It is the figure which showed the output from a vibration sensor. It is the figure which showed the time transition of the frequency of impact vibration. It is explanatory drawing of the piping clogging detection apparatus which concerns on 2nd Embodiment. It is an installation situation figure of the piping clogging detection device concerning a 3rd embodiment. It is an installation situation figure of the piping clogging detection device concerning a 3rd embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
In the following description, the same parts are denoted by the same reference numerals. Their names and functions are also the same. Therefore, detailed description thereof will not be repeated.
[First Embodiment]
FIG. 1 shows a pipe clogging detection device 1 according to an embodiment of the present invention. The pipe clogging detection device 1 is provided in the input pipe 3 of the garbage incinerator 2. As the input, the input pipe 3 is supplied with household garbage stored in a plastic garbage bag, oversized garbage or the like as it is or pulverized. Therefore, hereinafter, the input is simply referred to as garbage, and the garbage incinerator 2 is simply referred to as incinerator 2.

The incinerator 2 includes a furnace body 4 in which garbage is burned. The furnace body 4 is provided with an input port 5 through which dust is supplied, an input pipe 3 communicating with the input hole, a combustion burner (not shown), and an exhaust gas exhaust port 6. The inner wall of the furnace has a structure provided with a fireproof covering material such as a fireproof brick.
In the incinerator 2 having the above-described structure, garbage having various characteristics (hardness, weight, etc.) is input from the input port 5 provided on the upstream side of the input pipe 3. The thrown-in dust flows down through the feed pipe 3, enters the incinerator 2, and is combusted and thermally decomposed.

  In the input pipe 3 of this embodiment, the upstream part 3a following the input port 5 is arranged vertically, and the downstream part 3b is provided obliquely with respect to the vertical direction (lower right oblique shape in FIG. 1). In such a charging pipe 3, the deposit S is generated (initial clogging) on the pipe wall near the boundary between the furnace body 4 and the charging pipe 3, and then the deposit S on the upstream side or the center side of the pipe. Often increases (clogging grows).

The pipe clogging detection device 1 that detects the occurrence of such an adhering substance S and the accompanying blockage of the pipe has a plurality of vibration sensors 7 provided on the pipe wall of the input pipe 3. Furthermore, it has the determination part 8 which determines with the clogging having generate | occur | produced in the said piping, when the vibration detected by these several vibration sensors 7 reduces at a respectively different timing.
Specifically, as shown in FIG. 1 and FIG. 2, three vibration sensors 7 (7 </ b> A, 7 </ b> B, 7C). The vibration sensor 7 is composed of a piezoelectric element or the like, and can detect vibrations of 1 Hz to 10 kHz, for example, and is provided in a metal case so as to have excellent heat resistance.

Since the upstream part 3a of the input pipe 3 is vertical, the input dust collides with the lower side of the pipe downstream part 3b. Therefore, it is preferable that the three vibration sensors 7A, 7B, 7C are attached to the lower outer peripheral wall of the pipe downstream portion 3b.
The number of vibration sensors 7 attached is not limited to three. Two or four or more can be installed without any problem. Further, the installation location is preferably a location where piping clogging occurs. In many incinerators 2, a place where “pipe clogging” is likely to occur is often specified as an operation result, and therefore, selection of an installation place is relatively easy. When the place where the pipe clogging cannot be specified or the like, a plurality of vibration sensors 7 may be installed in a wide area of the input pipe 3 (for example, from the most upstream side to the most downstream side).

  The output signal of the vibration sensor 7 is amplified by the vibration measuring unit 9. FIG. 3 shows an example of vibration acceleration after amplification. It can be seen that shocking vibration is generated by the collision of the relatively hard and heavy solid contained in the thrown-in garbage with the tube wall. This waveform varies depending on the shape and weight of the dust and should be taken as an example. Such an output signal of the vibration sensor 7 is input to a determination unit 8 configured by a computer, and the presence / absence and status of the deposit S in the pipe are determined.

The determination process performed by the determination unit 8 is as follows.
FIG. 4 shows the number of shock vibrations (for example, the number of occurrences of a peak waveform having an acceleration equal to or higher than a predetermined threshold in one minute in the waveform shown in FIG. 3) based on the outputs from the vibration sensors 7A, 7B, and 7C. The time transition of the number of shock vibrations after calculation is shown.
As is apparent from FIG. 4, the number of impact vibrations per unit time for each of the three vibration sensors 7A, 7B, and 7C varies with time. Since the vibration sensor 7A is located below the vertical portion, the number of shock vibrations is the largest, and conversely, the vibration sensor 7C close to the incinerator 2 has the smallest number of shock vibrations.

In the X region of FIG. 4, the number of impact vibrations in all the vibration sensors 7A, 7B, and 7C decreases almost simultaneously. This is thought to be due to a decrease in the amount of waste input. Also, when the quality of the garbage changes and the proportion of hard and heavy inputs contained in the garbage changes, the outputs of all the vibration sensors 7 change in the same way.
On the other hand, in the Y area of FIG. 4, the number of times decreases in the order of vibration sensor 7C → vibration sensor 7B → vibration sensor 7A. That is, the number of shock vibrations (or the output value of the sensor itself) decreases from time T _C in the vibration sensor 7C, the number of shock vibrations decreases from time T _B in the vibration sensor 7B, and the vibration sensor 7A starts shock from time T _A. The number of vibrations is decreasing. Time T _C <time T _B <time T _A , and the time interval (for example, time T _A -time T _B ) is, for example, about 5 minutes.

As described above, the reduction of the outputs of the vibration sensors 7A, 7B, and 7C at different timings is due to the fact that the clogging of dust grows by the mechanism shown in FIG. That is, if for some reason dust adheres to the inner wall of the input pipe 3, new dust adheres toward the upstream side so as to catch on it, and eventually develops into a large blockage. Therefore, the output decreases in the order of the vibration sensor 7C, the vibration sensor 7B, and the vibration sensor 7A located on the downstream side. As described above, when vibration is reduced in order from the downstream side to the upstream side of the pipe, the determination unit 8 determines that clogging has occurred or is occurring in the pipe.
[Second Embodiment]
FIG. 5 shows a second embodiment of the pipe clogging detection device 1 according to the present invention. The major difference between the second embodiment and the first embodiment is that the installation location of the vibration sensor 7 with respect to the input pipe 3 is different. Although the description proceeds with the number of vibration sensors 7 being three, the number is not limited.

Since other configurations are substantially the same as those in the first embodiment, the description thereof is omitted.
For example, as shown in FIG. 5 (a), when the upstream portion 3a of the input pipe 3 is provided in a slanting direction downward to the right, and the downstream portion 3b of the input pipe 3 is provided in a vertical shape, the input is made from the input port 5. In FIG. 5 (a), the dust thus collected collides with the right side wall of the downstream portion 3b. Therefore, the vibration sensor 7C, the vibration sensor 7B, and the vibration sensor 7A are sequentially installed on the upstream side from the place where the dust is most likely to collide.

  In this piping structure, as shown in FIG. 5 (b), the adhesion of dust mostly starts from the downstream side (lower side) of the downstream portion 3b of the input piping 3, and the vibration sensor 7C located at the downstream side → The output decreases in the order of vibration sensor 7B → vibration sensor 7A. As described above, when vibration is reduced in order from the downstream side to the upstream side of the pipe, the determination unit 8 determines that clogging has occurred or is occurring in the pipe.

  Further, as shown in FIGS. 5C and 5D, in the case of the input pipe 3 formed only by the vertical portion, each is arranged along the circumferential direction of the pipe. When vibration is reduced in order along the circumferential direction, it is determined that the pipe is clogged. More preferably, considering a plane (horizontal plane) perpendicular to the axis of the pipe, a plurality of vibration sensors 7 may be installed at equal intervals on the outer peripheral surface of the pipe.

  In the case of the input pipe 3 arranged vertically, as shown in FIG. 5 (d), it is clear that the deposit S adheres along the circumferential direction of the inner wall of the pipe. ), When a plurality of sensors are installed as shown in FIG. 5D, the output decreases in the order of vibration sensor 7C → vibration sensor B → vibration sensor A. Thus, when the output of the vibration sensor 7 decreases at different timings, the determination unit 8 can determine that clogging has occurred or is occurring in the pipe.

Of course, when there are a plurality of clogging base points, a plurality of sensor arrangements as shown in FIG.
[Third Embodiment]
FIG. 6 shows a third embodiment of the pipe clogging detection device 1 according to the present invention. The major difference between the third embodiment and the first embodiment is that the structure (particularly, the vicinity of the installation portion) of the input pipe 3 where the vibration sensor 7 is installed is different. Although the description proceeds with the number of vibration sensors 7 being three, the number is not limited.

  As shown in FIG. 6, in this embodiment, the tube wall on which the vibration sensor 7 is provided is divided into three sections corresponding to each vibration sensor 7 by the beam member 10 (vibration suppressing means) having an H-shaped cross section. Such a structure makes it difficult for vibration generated in one section to propagate to adjacent sections, and the difference in vibration between sections becomes clearer, so that the accuracy of clogging determination can be increased. The cross-sectional shape of the beam member 10 is not limited to the H shape, and may be any as long as it has higher rigidity than the tube wall. Further, vibration propagation may be suppressed by providing a vibration isolating member between the sections.

Further, as shown in FIG. 7, for the same effect, the outer wall of the pipe is divided into three sections corresponding to each vibration sensor 7 by welding the rib 11 to the outer peripheral wall of the pipe where the vibration sensor 7 is provided. May be. This rib 11 will act as vibration suppression means.
The first to third embodiments described above should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  For example, although it has been described that the attachment of dust starts from the vibration sensor 7C, it may start from the vibration sensor 7B. In that case, the output of the vibration sensor 7C does not change, and the output decreases in the order of the vibration sensor 7B → the vibration sensor A. Further, the output of the vibration sensor 7B may be decreased after the output of the vibration sensor 7B is decreased in the order of the vibration sensor 7A → the vibration sensor 7C depending on the state of dust adhesion, or the output of the vibration sensor 7B may be decreased. It is also conceivable that the output of the vibration sensor 7C decreases almost simultaneously. It cannot be said that there is no possibility that the output decreases in the order of vibration sensor 7A → vibration sensor 7B → vibration sensor 7C. However, in any case, since the output of the vibration sensor 7 is reduced at different timings, the determination unit 8 is clogged in the pipe by detecting the change. Or it can be judged that it is occurring.

  Moreover, although the clogging determination based on the number of impact vibrations has been disclosed as a clogging determination method, the clogging determination method is not limited to this, and may be determined optimally according to the quality of the garbage and the generation / growth mechanism of clogging. For example, in the case of garbage that is relatively homogeneous (there is little variation in hardness and weight), it is difficult to extract shocking vibration as in the embodiment, so the change in the time average value of the vibration level (amplitude) You should pay attention to.

  Moreover, although the input piping 3 demonstrated the case of the combination of a vertical part and an inclination part, or the case of only a vertical part, it is applicable also to what consists only of an inclination part. In that case, a location where dust is most likely to collide is selected, and a plurality of sensors may be installed at the site.

DESCRIPTION OF SYMBOLS 1 Piping clogging detector 2 Garbage incinerator 3 Input pipe 3a Upstream part of input pipe 3b Downstream part of input pipe 4 Furnace body 5 Input port 6 Outlet port 7 Vibration sensor (7A, 7B, 7C)
8 Judgment part 9 Vibration measurement part 10 Beam member (vibration suppression means)
11 Rib (vibration suppression means)

Claims (9)

In the pipe clogging detection device that detects clogging in the pipe into which the input is introduced from above,
A plurality of vibration sensors are attached to the pipe wall of the pipe, and a determination unit is provided for determining that the pipe is clogged when vibrations detected by the plurality of vibration sensors are reduced at different timings. Piping clogging detection device characterized by that.   The piping clogging detection device according to claim 1, wherein the plurality of vibration sensors are respectively arranged from the upstream side to the downstream side of the piping.   The pipe clogging detection apparatus according to claim 2, wherein the determination unit determines that clogging has occurred in the pipe when vibration is reduced from the downstream side to the upstream side of the pipe.   The piping clogging detection device for a pipe according to claim 2 or 3, wherein the plurality of vibration sensors are provided on a side wall of the pipe and on a side on which an input collides.   The piping clogging detection apparatus according to claim 1, wherein the plurality of vibration sensors are respectively disposed along a circumferential direction of a pipe wall of the pipe.   The pipe clogging detection apparatus according to claim 5, wherein the determination unit determines that clogging has occurred in the pipe when vibration is reduced along a circumferential direction of the pipe.   The said piping is provided with the vibration suppression means which suppresses that a vibration propagates through the said piping, The said vibration sensor is arrange | positioned for every area divided | segmented by the said vibration suppression means. Item 7. The piping clogging detection device according to any one of Items 1 to 6.   The pipe clogging detection apparatus according to any one of claims 1 to 7, wherein the pipe is an input pipe for supplying the input into a garbage incinerator. The vibration of the pipe is detected by a plurality of vibration sensors attached to the pipe wall of the pipe into which the input is introduced from above,
A piping clogging detection method, wherein when the detected vibrations are reduced at different timings, it is determined that clogging has occurred in the piping.