JP2000146725A - Method and device for measuring amount of wear of layer inner pipe due to fluid medium in a fluidized bed device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To predict risk for the local or global damage of a heat transfer pipe by quantitatively measuring the three-dimensional distribution characteristic of the in-layer fluctuating load in real time in all operating states including hot operation as well as cold operation while the fluidized bed device is operating. SOLUTION: In a method for measuring the fluctuating load and the amount of wear of a layer inner pipe of a fluid medium in a fluidized bed device with a group of pipes in the fluidized bed, a hole 501e is made to the pipe wall of a dummy pipe 501 for simulating the inner pipe of the fluidized bed, on end of an object 503a for propagating pressure is joined to the end part of the dummy pipe 501, pressure fluctuation due to the collision of the fluid medium that is propagated through the inside of the dummy pipe 501 from the hole 501e of the dummy pipe 501 is measured by a pressure sensor 903a that is connected to the other end of the object 503a, the fluctuating load of the fluid medium in the fluidized bed device that is in a proportional relationship with the above pressure fluctuation is estimated, and the amount of wear of the layer inner pipe due to the fluctuating load is predicted from a fluctuating load estimation value.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluidized bed apparatus used for all purposes such as improving heat exchange performance and accelerating a reaction. The present invention relates to a method and an apparatus for enabling a load distribution to be quantitatively measured and for estimating a pipe fatigue degree and a pipe wear amount with high accuracy.

[0002]

2. Description of the Related Art Fluidized bed apparatuses are generally and widely used for all purposes such as improving heat exchange performance and accelerating reactions. As one example, in the field of thermal power plants, fluidized bed boilers have been receiving attention in order to reduce CO ₂ emissions and fuel consumption. This type of boiler is characterized by high heat transfer efficiency because coal as fuel is mixed with a fluid medium as granular solids and burned.

FIG. 14 is a schematic view of a fluidized-bed boiler. A heat transfer tube 1 through which water flows is installed in the furnace 6, and a fluid medium 5 is filled so as to fill the heat transfer tube 1. Fluid medium 5 is fluidized by hot air blown up through a blower (not shown), wind box 4 and air distribution plate 3, and bubbles 2 containing fluid medium 5 are transferred to heat transfer tube 1.
A fluctuating load acts on the heat transfer tube 1 when it collides with.

[0004] The fluctuating load is random in time and space, but when the fluctuating load acts on the heat transfer tube 1 repeatedly, repetitive stress is generated on the heat transfer tube 1 as the heart and the supporting structure thereof. I do. Therefore, heat transfer tube 1
It is important to measure the distribution characteristics of the fluctuating load in order to evaluate the safety against wear of the steel and the fatigue of the supporting structure and to obtain a highly reliable structure based on the evaluation.

FIG. 21 shows a state in which a random fluctuating load (Q _i , Q _j, etc.) due to the flowing medium acts on the heat transfer tube 1. In order to strictly evaluate the deformation amount (u _i , u _j, etc.) of the heat transfer tube 1, the distribution of the variable load (Q _i , Q _j, etc.) in the tube axis direction,
It is necessary to measure data representing randomness such as correlation and phase between fluctuating loads with high accuracy. Specifically required data are a power spectrum showing the square value of the variable load for each frequency band component, a coherence spectrum showing the correlation between the variable loads for each frequency band component, and a phase between the variable loads for the frequency band. There is a frequency spectrum such as a phase spectrum shown for each component, and it is necessary to incorporate these spectra into the deformation evaluation of the heat transfer tube. This evaluation method will be specifically described below.

To calculate the amount of deformation of the heat transfer tube, a calculation model (lumped mass model) as shown in FIG. 22 is required. In FIG. 22, the number of mass points is set to 8 (m _{1 to} m ₈ ), but this number corresponds to the number of strain measurement target tubes 201 to 208 in the load measurement device (FIG. 15) described later. .

In this model, the rigidity k _1-
It is assumed that k ₈ and damping constants c _{1 to} c ₈ are set, and dynamic loads Q ₁ (t) to Q ₈ (t) as external forces act on each mass point. In this model, the mass matrix is [M], the rigidity matrix [K], and the damping matrix is [C], and the dynamic load vector acting on each mass point is represented by the following equation (1).

[0008]

(Equation 1) Here, the suffix T means transposition of a vector or a matrix.

[M], [C], [K] and {Q (t)}
Is used, the vibration equation of the heat transfer tube when a dynamic load acts is given by the following equation (2).

(Equation 2) Becomes {U (t)} is a vertical displacement vector of each mass point in FIG. 22, and vector components u ₁ (t) to u _1
8 (t) is expressed by the following equation (3).

[0010]

(Equation 3)

In equation (2), Represents

Based on the stochastic vibration analysis method, the equation for evaluating the amount of deformation of the heat transfer tube is derived from the following equation (4).

[0013]

(Equation 4)

Here, u_i,_rmsIs the heat transfer shown in FIG.
Root meansquare value of displacement of mass point i of pipe model (hereinafter,
Effective value). S_Q,_ev(Ω) is the e-th quality
Fluctuating load Q acting on a point (hereinafter referred to as mass point e)_e(T)
Power spectrum, S_Q,_vv(Ω) is the v-th mass point
(Hereinafter referred to as mass point v)_v(T)
Power spectrum, W_Q,_ev(Ω) is Q acting on mass point e_e
(T) and Q working on mass point v_v(T) coherence spec
Torr, θ_Q,_ev(Ω) is Q_e(T) and Q_v(T) place
It is a phase spectrum. n is the number of mass points (= 8), m is unique
The number of modes, φ _ijIs the j-order eigenvalue normalized by [M]
The component of the node i of the mode vector.

H _j (ω) is the frequency response function of the j-order eigenmode, the damping ratio β _i of the j-th mode of the pipe having the same length in the pipe axis direction as the pipe model shown in FIG. Number ω
_j , the frequency ω of the variable load and the imaginary number γ can be calculated according to the following equation (5).

[0016]

(Equation 5) H _j (ω) calculated by the equation (5) is input to the equation (4), and the power spectrum S _Q ,
_ee (ω) and S _Q , _vv (ω), coherence spectrum W _Q , _ev (ω), phase spectrum θ _Q ,
If input _ev the (omega) in equation (4) _{u i, rms} can be calculated.

As described above, the power spectrum S _Q of the fluctuating load acting in the direction of the tube axis of the heat transfer tube shown in FIG.
_ev (ω), coherence spectrum W _Q ,
If physical quantities representing the randomness of the fluctuating load such as _ev (ω) and phase spectrum θ _Q , _ev (ω) can be measured, it can be understood that the strict evaluation of the heat transfer tube deformation can be performed by the equation (4).

Two conventional methods and apparatus for measuring the fluctuating load distribution in a fluidized bed apparatus will be described. First,
FIGS. 15 to 19 show a first method and apparatus (Japanese Patent Laid-Open No. 10-48075). The basic concept of the load distribution measuring method in the apparatus shown in FIGS. 15 to 19 is that at least one of the pipe itself or a dummy pipe simulating the pipe is divided into at least two or more in the pipe axis direction and divided. At least one or more strain gauges are attached to the pipe, and the variable load distributed in the pipe axis direction is measured.
Hereinafter, description will be made in order from FIG. 15 to FIG.

The apparatus shown in FIG. 15 attaches the strain gauge 15 to the pipes 201 to 208 to be measured divided in the pipe axis direction, and measures the strains 201Z to 208Z when the pipes 201 to 208 are bent in the vertical direction. This makes it possible to evaluate the fluctuation load distribution in the pipe axis direction.

FIGS. 16, 17 and 18 show a cross section taken along the line AA, a line BB and a line CC of FIG. 15, respectively.
FIG. 17 shows the measurement target pipe 20 of the measurement target pipes 201 to 208 to which the strain gauge 15 is attached in FIG.
3 is a sectional view taken along line BB of FIG. Pipe 2 to be measured
Numeral 03 is supported by support tubes 212 to 214 which do not divide both ends of the target tube 203 via a T-shaped support plate 210.

FIG. 16 shows a cross section of the end of the support pipes 212 to 214 shown in FIGS. FIG.
6 that the ends of the support tubes 212 to 214 are joined to the support plate 215. Further, as shown in FIG. 15, the other ends of the support tubes 212 to 214 are connected to a support plate 216.
It is supported by.

FIG. 18 shows the strain gauge 15 in FIG.
3 shows a cross section at a center point of a distance from the right end of the measurement target tube 203 to the left end of the measurement target tube 204 among the measurement target tubes 201 to 208 to which the measurement target tubes 201 to 208 are attached. FIG.
As shown in FIG. 8, the support tubes 211 to 21
4 and only the measurement target pipe 203 and the measurement target pipe 204 exist.
Are not continuous.

The connection between the strain gauge 15 shown in FIG. 15 and the variable load analyzer 904 needs to be connected by a lead wire 16.
16 can be pulled out from the wiring outlet 217 provided in the support plate 215 in FIG.

Since the present apparatus has the above-described structure, it is possible to evaluate the distribution characteristics in the pipe axis direction of the variable load acting on the pipes 201 to 208 to be measured. Hereinafter, the device shown in FIG. 15 is referred to as a tube axial dynamic load distribution measuring device, and an application example of the present device will be described below.

FIG. 19 shows a fluidized bed apparatus viewed from the tube axis direction of the heat transfer tube. The tube group 9 is fixed to the casing 106 so that the tube group 9 is buried in a fluid medium (not shown) during operation of the apparatus. Any position of such a device (for example, 2
15a to 215i), the above-mentioned tube axial direction dynamic distribution measuring device can be installed, and the fluctuation load distribution in the furnace width direction and the height direction in the fluidized bed device can be measured.

However, the conventional apparatus shown in FIG. 15 can be used in an operation state (for example, a cold operation state) of a fluidized-bed boiler in which components such as the strain gauge 15 and the pipes 201 to 208 to be measured are not burned out. The operating state of the fluidized bed boiler where parts are burned out (hot operating state,
(About 800 ° C. or higher), there was a problem that it could not be used.

On the other hand, another conventional measuring method (JP-A-61-285384) will be described below. FIG. 20 shows a fluidized bed apparatus without a tube bank. The method shown in FIG. 20 employs a wind box 4 provided below a furnace 6 of a fluidized bed apparatus.
By measuring the pressure fluctuations of the inside and the freeboard part 7 of the furnace 6 with the pressure gauge 104 and the pressure gauge 107, respectively,
This is for measuring the variable load of the flowing medium 5. FIG. 20 shows a state in which bubbles 2 are generated inside the fluid medium 5 via the air dispersion plate 3.

The method shown in FIG. 20 evaluates the fluctuating load in the fluidized bed by measuring the pressure fluctuation.
Unlike the above-described strain gauge type load measuring method, there is no problem in use such as burnout of the gauge, and therefore there is an advantage that it can be applied to a hot operation state.

[0029]

However, the method shown in FIG. 20 measures only two pressure fluctuations in the wind box 4 of the fluidized bed apparatus and the freeboard section 7 in total, so that the fluctuating load in the fluidized bed is measured. Although the overall behavior of can be measured, the three-dimensional distribution of the fluctuating load in the layer cannot be evaluated. Further, the measuring method of FIG. 20 is invented for a fluidized bed apparatus without a tube bank, and does not mention the fluctuating load in the fluidized bed in the case where there is a tube bank.

In the case of a fluidized bed having a tube group, it is necessary to measure the three-dimensional distribution characteristics of the fluctuating load in detail as much as possible due to problems such as local destruction due to abrasion of the tube. Cannot measure the three-dimensional distribution of

An object of the present invention is to solve the above-mentioned drawbacks in the prior art and realize the following. (1) In the operating state of the fluidized bed apparatus, it is possible to quantitatively measure the three-dimensional distribution characteristics of the fluctuating load in the bed in real time in all operating states including not only the cold operation but also the hot operation. A method and apparatus are provided. (2) Using the three-dimensional distribution of the fluctuating load measured in (1), it is possible to evaluate the heat transfer tube wear amount with high accuracy, and predict the danger of local or total damage to the heat transfer tube. enable.

[0032]

The above objects are achieved by the following means. (1) In a method for measuring a fluctuating load in a fluidized bed apparatus having a tube group in a fluidized bed, a hole is formed in a pipe wall of a dummy pipe simulating an inner layer pipe, and pressure is transmitted to an end of the dummy pipe. One end of a possible object is joined, a pressure sensor is connected to the other end of the object, and a pressure fluctuation due to collision of a flowing medium propagating from the hole of the dummy pipe through the inside of the dummy pipe is measured by the pressure sensor, A method for measuring a fluctuating load of a fluidized medium in a fluidized bed apparatus proportional to the pressure fluctuation based on the measured value.

(2) In the method of measuring the wear amount of a tube in a fluidized bed apparatus having a tube group in the fluidized bed, a hole is formed in a wall of a dummy tube simulating the tube in the bed. One end of an object capable of transmitting pressure is joined to the end, a pressure sensor is connected to the other end of the object, and the pressure fluctuation due to the collision of the flowing medium propagating from the hole of the dummy pipe through the inside of the dummy pipe is measured. A method of measuring with a pressure sensor, measuring a fluctuating load of a fluid medium in a fluidized bed apparatus in a proportional relationship with the pressure fluctuation based on the measured value, and measuring an in-layer pipe wear amount from the fluctuating load measured value.

The present invention also includes an apparatus for measuring a fluctuating load or a wear amount of a pipe in a bed in the following fluidized bed apparatus.

(3) In a device for measuring a fluctuating load in a fluidized bed apparatus in which a tube group is arranged in a fluidized bed, a dummy tube simulating a tube arranged in the fluidized bed and having a hole formed in a tube wall is used. Fluctuation in a fluidized bed apparatus which is arranged in a fluidized bed, one end of an object capable of transmitting pressure is joined to the end of the dummy pipe, and a variable load analyzer is connected to the other end of the object via a pressure sensor. A measuring device for fluctuating load in a fluidized bed device connected to a load measuring device.

(4) In an apparatus for measuring the amount of wear in a fluidized bed in a fluidized bed apparatus in which a group of pipes is arranged in a fluidized bed, a pipe arranged in the fluidized bed is simulated, and a hole is formed in a pipe wall. A dummy pipe is disposed in a fluidized bed, one end of an object capable of transmitting pressure is joined to an end of the dummy pipe, and a variable load analysis device and an in-layer pipe wear amount are connected to the other end of the object via a pressure sensor. A device for measuring the amount of wear in a tube in a fluidized bed device connected to an analyzer.

(5) In a device for measuring a fluctuating load in a fluidized bed apparatus in which a tube group is arranged in a fluidized bed, a tube axis of a dummy tube imitating a tube arranged in the fluidized bed and having both ends opened. Plug the plug in the middle of the direction to divide the inside of the dummy pipe into two chambers, make holes in the pipe wall of the dummy pipe in each chamber, A fluctuating load measuring device for a fluidized medium in a fluidized bed device in which one end is joined and a fluctuating load analyzing device is connected to the other end of the object via a pressure sensor.

(6) In a device for measuring a wear amount of a tube in a fluidized bed in which a tube group is arranged in the fluidized bed, a dummy tube imitating a tube arranged in the fluidized bed and having both ends opened. The middle of the dummy pipe is divided into two chambers, and holes are made in the wall of the dummy pipe in each chamber, and pressure can be transmitted to both ends of the dummy pipe. A device for measuring the amount of wear in a bed in a fluidized bed apparatus in which one end of a simple object is joined, and the other end of the object is connected through a pressure sensor to a variable load analysis device and an in-layer tube wear amount analysis device.

Here, a device for measuring the fluctuating load or the amount of wear in the fluidized bed in the fluidized bed device is provided by using a dummy tube having substantially the same length in at least one of the width direction, the height direction and the depth direction in the fluidized bed. By adopting a configuration in which a plurality of tubes are arranged in parallel in any direction, it is possible to measure a fluctuating load in a two-dimensional or three-dimensional space in a fluidized bed or a wear amount of a pipe in a bed.

According to the above configuration of the present invention, the pressure fluctuation generated when the flowing medium collides with the pipe is measured by propagating through the hole of the dummy pipe, the inside of the dummy pipe and the inside of the object, and the flowing medium is measured. Evaluate the fluctuating load generated by colliding with, and based on this fluctuating load,
The amount of wear can be evaluated.

As described above, if a method is used in which a plurality of dummy pipes are provided at various positions in the fluidized bed and a method for evaluating a fluctuating load based on pressure fluctuation due to the collision of the fluidized medium is used, the following conditions can be obtained. It is possible to measure the three-dimensional distribution of the fluctuating load in the fluidized bed not only in the cold operating state but also in all operating states including the hot operating state, and the fatigue and wear of the pipes arranged in various places in the fluidized bed The amount can be evaluated.

The tubes arranged in the bed of the fluidized bed apparatus to which the measuring method and apparatus of the present invention are applied are used as heat transfer tubes, reaction tubes, etc., for heating gas or water, and for various reactions. It is a pipe for heat recovery or a pipe for temperature control in the bed used for cooling the fluidized bed. Examples of the fluidized bed apparatus for heat recovery include a fluidized bed boiler, a super heater for heating steam of a steam boiler with a non-corrosive gas, a general process gas heating tube, and a reactive gas reaction tube. The fluidized bed apparatus for controlling the temperature in the bed is a heat transfer tube or the like that controls the temperature in the bed such as a refuse incinerator.

[0043]

Embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows a dummy tube 501 taken out of a plurality of dummy tubes 501 installed in a fluidized bed. The feature of this embodiment is that the heat transfer tube wear amount is estimated from the fluctuating load measured in this way using the dummy tube 501 and converted into a pressure fluctuating load in the fluidized bed. Hereinafter, such a dummy tube 5 for pressure measurement will be described.
01 is referred to as a pressure measurement target pipe 501.

The embodiment shown in FIG. 1 will be described in detail below. In the present embodiment, a plug 502 is plugged in the middle of the pressure measurement target pipe 501 in the pipe axis direction, the inside of the pipe 501 is divided into two chambers, and the pressure measurement unit 501c is separately provided in each chamber.
501d is provided.

FIG. 2 is an enlarged view of the pressure measuring section 501c. In the pressure measuring unit 501c, a hole 501e is formed in the tube 501, and a curing sheet 501f is attached so as to cover the hole 501e. Although the size and shape of the hole 501e are not particularly specified, it is necessary to use a fireproof sheet made of, for example, glass fiber or the like as the curing sheet 501f covering the hole 501e. With such a structure, it is possible to introduce only the pressure fluctuation of the gas in the fluidized bed into the pipe 501 through the hole 501e while keeping the fluid medium in the bed from entering the pipe 501 through the hole 501e. It has a mechanism. In addition,
Pressure fluctuation measuring unit 501c using such a hole 501e
A measuring unit 501d similar to the above is provided in the other chamber divided into two chambers inside the tube 501.

As an object for transmitting the pressure fluctuation propagated into the pipe 501 via the pressure measuring section 501c to the pressure sensor 903a, for example, a steel flexible hose 503a shown in FIG. Left end 50
1a and the pressure sensor 903a. Thus, the pressure fluctuation propagated into the pipe 501 via the pressure measuring unit 501c propagates inside the steel flexible hose 503a attached to the left end 501a of the pipe 501, and the pressure sensor 903a
Is measured by the fluctuating load analysis device 904. In addition,
A heat transfer tube wear amount analysis device 905 is attached to the analysis device 904, and the heat transfer tube wear amount is evaluated by this device 905.

Similarly, the pipe 50 is connected via the pressure measuring section 501d.
The steel flexible hose 5 shown in FIG. 1 is used as an object for transmitting the pressure fluctuation propagated into the pressure sensor 1 to the pressure sensor 903b.
This is connected to the right end 501b of the tube 501 and the pressure sensor 903b using 03b. Thus, the measuring unit 501
The pressure fluctuation propagated into the pipe 501 via the line d propagates through the inside of the flexible steel hose 503b, and is measured by the fluctuation load analyzer 904 via the pressure sensor 903b.

The above-mentioned steel flexible hoses 503a, 503
b can be extended to the outside of the fluidized bed apparatus, and outside the fluidized bed apparatus, each of the pressure sensors 9
If the pipes 03a and 903b are connected, it is possible to easily measure the distribution of pressure fluctuations in the fluidized bed in the tube axis direction when there is a tube group. For example, the pipes can be arranged in various places in the furnace 6 shown in FIG. The wear amount of the heat transfer tube 1 thus performed can be evaluated.

It should be noted that the pressure measuring section 501c and the mounting section of the pressure measuring section 501d shown in FIG.
By arbitrarily changing the distances Lc and Ld from the center 501b, it is possible to measure the pressure fluctuation at an arbitrary position in the tube axis direction. The pressure measurement using the pressure measurement target tube 501 according to the embodiment shown in FIG. 1 is applicable to both normal pressure and pressurized fluidized beds.

The reason why the fluctuation load can be evaluated by measuring the pressure fluctuation in the layer by the embodiment shown in FIG. 1 and the wear amount of the heat transfer tube can be measured from the fluctuation load will be described in the following order.

First, the reason why the fluctuating load can be evaluated from the pressure fluctuation in the layer will be described. FIG. 3 is a diagram drawn focusing on the pressure measuring unit 501d in FIG. 1. The difference from FIG. 1 is that a pipe 209 for measuring a pipe strain 209z of the pressure measurement target pipe 501 is provided at the position of the pressure measuring unit 501d. Support plate 22
0 is installed in the pressure measurement target pipe 501 via the “0”.

As described in the prior art, the pipe strain 20
If 9z is used, the bubble 2 collides with the tube 209 (specifically, the fluid medium 5 contained in the bubble 2 collides).
Can be measured.

On the other hand, at the same time when the bubble 2 collides with the tube 209, the pressure fluctuation due to the passage of the bubble 2 was measured by the pressure measuring section 501 d close to the tube 209. There is a strong correlation between the load generated in (1), that is, the variable load, and in conclusion, it was experimentally obtained that the reaction load value was proportional to the pressure fluctuation value. This finding will be described with reference to FIGS.

FIG. 4 shows the frequency on the horizontal axis, the vertical axis on the vertical axis, the square of the pressure fluctuation measured by the measuring section 501d, and the pipe strain 209z.
4 shows a frequency spectrum employing a value obtained by standardizing the square value of the variable load converted from the square value of the rms value of the variable load.

As shown in FIG. 4, the dominant frequencies of the fluctuating load and the pressure fluctuation are almost the same, and both are 2 to 4 Hz.
It can be seen that the frequency component is large. This frequency 2-4
The Hz band is called a bubble collision frequency band.

As a result of examining the relationship between the fluctuation load and the pressure fluctuation in the bubble collision frequency band shown in FIG. 4 from an experiment in which the rising speed of the bubble 2 shown in FIG. 3 was changed, a proportional relationship was established as shown in FIG. I found out. This is the reason why the fluid medium fluctuation load can be evaluated by measuring the pressure fluctuation.

Next, the reason why the heat transfer tube wear amount can be estimated from the variable load will be described. FIG. 6 shows a time history waveform of the variable load. The horizontal axis in FIG. 6 indicates time t (h), and the vertical axis indicates a value obtained by making the variable load amplitude F dimensionless by the maximum value Fmax of the variable load amplitude. Therefore, a point where the value on the vertical axis is 1 indicates a point where the fluctuating load is equivalent to Fmax.

As described above, the fluctuating load is generated by the collision of bubbles containing the flowing medium. This can be seen from the fact that the fluctuating load amplitude F is large on the plus side at the bubble collision time as shown by the arrow in FIG.

The heat transfer tube wear amount δ is proportional to the value obtained by multiplying the maximum value Fmax of the variable load amplitude by the number of occurrences N of Fmax (in other words, the number of collisions of bubbles N), as shown in equation (1).

Δ = α × Fmax × N (1) Here, α is a coefficient that depends on the material properties of the heat transfer tube, and is a coefficient representing the easiness of wear of the heat transfer tube. N in equation (1)
Can be evaluated by multiplying the dominant frequency f of the fluctuating load in FIG. 4 by the measurement time t (h) from the start of operation in FIG. 6, as shown in the following equation (2). N = f × t (2)

By substituting equation (2) into equation (1), equation (3) is obtained. The equation (3) is incorporated in the heat transfer tube wear amount analysis device 905 in FIG. 1, and the maximum value Fmax and the dominant frequency f of the variable load amplitude analyzed by the variable load analysis device 904 are calculated in addition to the coefficient α and the measurement time t. If the data can be input to the device 905, the heat transfer tube wear amount δ can be easily evaluated.

Δ = α × Fmax × f × t (3) As described above, if the equation (3) is incorporated in the apparatus shown in FIG. 1, it is possible to quantitatively know the replacement time of the worn heat transfer tube. it can. This will be described with reference to FIG.

FIG. 7 shows the operation time t of the fluidized bed apparatus on the horizontal axis.
Taking (h), the vertical axis represents the dimensionless value obtained by dividing the heat transfer tube wear amount evaluated by equation (3) by the allowable value of the heat transfer tube wear amount.

FIG. 7 shows an evaluation of the heat transfer tube wear when the coefficient α and the dominant frequency f in equation (3) are kept constant. As shown in FIG. 7, when the apparatus according to the present invention shown in FIG. 1 is used, even when the maximum value Fmax of the variable load amplitude is large, medium, and small, the heat transfer tube wear amount δ
Can be estimated when it reaches the allowable value.

FIG. 8 shows the operation time t of the fluidized bed apparatus on the horizontal axis.
(H) is plotted on the vertical axis to obtain a dimensionless value obtained by dividing the heat transfer tube wear amount evaluated by the equation (3) by the allowable value of the heat transfer tube wear amount. FIG. 8 is an evaluation of the heat transfer tube wear when the coefficient α and the maximum value Fmax of the fluctuating load amplitude in equation (3) are fixed.

As shown in FIG. 8, when the apparatus according to the present invention shown in FIG. 1 is used, even when the frequency f of the fluctuating load is different from high, medium and low, it is possible to estimate the time when the heat transfer tube wear amount δ reaches the allowable value. it can.

As described above, when the apparatus according to the present invention is used, it is possible to quantitatively estimate the replacement time of the worn heat transfer tube.

Another embodiment of the present invention will be described with reference to FIGS. 9 to 9 in order to measure the distribution of the fluidized medium fluctuating load in the pipe axis direction in more detail and to evaluate the amount of wear of the heat transfer pipes at various places in the bed with high accuracy. 11 will be described.

FIG. 9 shows five dummy pipes simulating the heat transfer pipes in the fluidized bed, and the five adjacent pipes are pressure measurement target pipes 601 to 601.
The side view of the apparatus which fixed 605 with the support plates 610 and 611 is shown. FIG. 11 shows a cross section taken along the line BB in FIG. 9, and it can be seen from FIG. 11 that the pressure measurement target tubes 601 to 605 are arranged at predetermined intervals. FIG. 10 shows a cross section taken along line AA of the support plate 610 in FIG. 9, and it can be seen that the pressure measurement target tubes 601 to 605 are fixed by the rhombus-shaped support plate 610.

Looking at FIG. 9, the individual pressure target pipes 60
A plug 502 is disposed in each of the tubes 1 to 603 in the middle of the tube axis direction, and the inside of each of the tubes 601 to 603 is divided into two chambers by the plug 502. Further, one ends of steel flexible hoses 601a to 603a and 601b to 603b are attached to the ends of the individual tubes 601 to 603. The other ends of the steel flexible hoses 601a to 603a and the steel flexible hoses 601b to 603b are connected to the variable load analyzing device and the heat transfer tube wear amount analyzing device (both three members) via a pressure sensor by a connection method similar to that shown in FIG. (Not shown).

The pressure measurement target pipe 601 which is close to such a pressure measurement target pipe 601
To 605, the individual pressure measurement target units 601c to 601c
If the positions of 03c and the pressure measurement target parts 601d to 603d are made different in the tube axis direction as shown in FIG. 9, the distribution of the pressure fluctuation in the tube axis direction can be measured in more detail.

Further, the present apparatus shown in FIGS.
If the fluidized bed apparatus is installed at arbitrary positions (for example, 215a to 215i) in the width direction and the height direction of the fluidized bed apparatus, the three-dimensional distribution of the fluctuating load in the bed can be easily measured. The heat transfer tube wear can be evaluated with high accuracy.

Another embodiment for measuring the three-dimensional distribution of the fluidized medium fluctuating load in detail and highly accurately evaluating the abrasion loss of the heat transfer tube at various points in the layer will be described with reference to FIGS. 12 and 13. .

FIG. 12 is a schematic diagram of a cross section in which the fluidized bed apparatus is vertically divided. Inside the furnace 6, in addition to the heat transfer tube 1, a dummy tube (pressure measurement target tube) supported by a support member 801
701 to 703 are installed, and a fluid medium 5 is provided in the bed.
Is filled. The fluid medium 5 is fluidized by the air from the air distribution plate 3.

The pressure measuring pipes 701 to 703 arranged in the height direction inside such a fluidized bed apparatus are used, and plugs 502 are provided inside the pipes 701 to 703 to divide the pipe into two chambers. Divided into And pipes 701 to 703
The pressure measuring units 701c to 703c and the pressure measuring unit 701
d to 703d, steel flexible hoses 701a to 703a and steel flexible hoses 701b to 703b at both ends of pipes 701 to 703, and a fluidized bed apparatus (furnace) 6
To extend outside.

The other ends of the steel hoses 701a to 703a and the steel flexible hoses 701b to 703b are connected to the variable load analysis device and the heat transfer tube wear amount analysis through pressure sensors in the same connection method as shown in FIG. A device (all three are not shown) is installed. With such a mechanism, the flow load distribution in the height direction in the fluidized bed apparatus (furnace) 6 can be easily measured, and the wear amount of the heat transfer tube in each place can be evaluated with high accuracy.

In FIG. 12, the pressure measuring unit 701
The positions of c to 703c and the pressure measuring units 701d to 703d in the tube axis direction can be set arbitrarily, and the positions are not particularly specified here.

FIG. 13 is a plan view when the dotted line AA in FIG. 12 is viewed from above the fluidized bed apparatus (furnace) 6. As shown in FIG. 13, some of the plurality of dummy tubes 703 to 709 arranged on the plane of the furnace 6 are used as pressure measurement target tubes 703, 705, 707, and 709,
These pressure measurement target tubes 703, 705, 707, 709
703c, 705c, 707c, 709
c, 703d, 705d, 707d, 709d are provided,
Steel flexible hoses 703a, 705a, 707 are provided at both ends of the pressure measurement target pipes 703, 705, 707, 709.
a, 709a, 703b, 705b, 707b, 709
A variable load analyzer and a heat transfer tube wear analyzer (not shown) are installed at the other end of b through a pressure sensor in the same connection method as shown in FIG.

With such a configuration, the distribution of the flow load in the furnace width direction and the depth direction in the fluidized bed apparatus (furnace) 6 can be easily measured, and the wear amount of the heat transfer tube at each location can be evaluated with high accuracy.

In FIG. 13, the pressure measurement unit 703
c, 705c, 707c, 709c, 703d, 705
The positions of d, 707d, and 709d in the tube axis direction can be arbitrarily set, and the positions are not specified here.

As described above, the three-dimensional distribution of the flow load in the fluidized bed apparatus can be easily measured by the method shown in FIGS. 12 and 13, and the wear of the heat transfer tube at each location can be evaluated with high accuracy.

[0082]

According to the present invention, the following items are realized. (1) In the operating state of the fluidized bed apparatus, the three-dimensional distribution characteristics of the fluctuating load in the bed can be measured in real time with high accuracy in all operating states including not only the cold operation but also the hot operation. . (2) Using the three-dimensional distribution of the fluctuating load measured in (1), highly accurate heat transfer tube wear evaluation can be realized. (3) Based on the evaluation result in (2), it is possible to predict the danger of local or total destruction of the heat transfer tube. (4) According to the risk of heat transfer tube destruction evaluated in (3), the replacement part and replacement time of the heat transfer tube are quickly and accurately evaluated, and the rational operation of the heat transfer tube group and the entire fluidized bed apparatus is performed. Make it feasible.

[Brief description of the drawings]

FIG. 1 is a diagram showing a variable load measuring device according to an embodiment of the present invention.

FIG. 2 is a partially enlarged view of FIG.

FIG. 3 is a diagram showing a variable load measuring device according to an embodiment of the present invention.

FIG. 4 is a diagram illustrating a method of converting a pressure fluctuation measured by the device according to the embodiment of the present invention into a variable load.

FIG. 5 is a diagram illustrating a method for converting a pressure fluctuation measured by the device according to the embodiment of the present invention into a variable load.

FIG. 6 is a diagram showing a time history waveform of a variable load according to the embodiment of the present invention.

FIG. 7 is a diagram showing a heat transfer tube wear amount evaluation in the embodiment of the present invention.

FIG. 8 is a diagram showing a heat transfer tube wear amount evaluation in the embodiment of the present invention.

FIG. 9 is a diagram illustrating another embodiment of the present invention.

FIG. 10 is a sectional view taken along line AA of FIG. 9;

FIG. 11 is a sectional view taken along line BB of FIG. 9;

FIG. 12 is a diagram illustrating another embodiment of the present invention.

FIG. 13 is a view of a cross section taken along line AA of FIG. 12;

FIG. 14 is a schematic view of a fluidized-bed boiler according to the present invention.

FIG. 15 is a view showing a fluctuating load measuring device according to a conventional technique.

16 is a sectional view taken along line AA of FIG.

FIG. 17 is a sectional view taken along line BB of FIG. 15;

18 is a sectional view taken along line CC of FIG.

FIG. 19 is a view showing a fluctuating load measuring device according to a conventional technique.

FIG. 20 is a diagram showing a fluctuating load measuring device according to the related art.

FIG. 21 is a diagram showing the relationship between a fluctuating load acting on the heat transfer tube in the tube axis direction and the amount of deformation of the heat transfer tube.

FIG. 22 shows a lumped mass model of a pipe.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Heat transfer tube 2 Bubble 3 Air dispersion plate 4 Wind box 5 Fluid medium 6 Furnace 7 Free board 9 Tube group 15 Strain gauge 16 Lead wire 106 Casing 501 Pressure measurement object pipe 501e Hole 501f Curing sheet 501c, 501d Pressure fluctuation measurement unit 502 Tap 503 (503a, 503b) Steel flexible hose 601 to 605 Pressure measurement target pipe 601a to 603b Steel flexible hose 601c to 603d Pressure measurement target portion 610, 61
DESCRIPTION OF SYMBOLS 1 Support plate 701-709 Dummy tube (pressure measurement target tube) 701c-709d Pressure measurement part 701a-709b Steel flexible hose 801 Support member 903 (903a, 903b) Pressure sensor 904 Variable load analyzer 905 Heat transfer tube wear analyzer

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Kazunori Ohno 6-9 Takaracho, Kure City, Hiroshima Prefecture Inside the Kure Factory (72) Inventor Shoji Morikawa 6-9 Takaramachi Kure City, Hiroshima Prefecture 6-9 Babcock Hitachi, Ltd. F term in Kure factory (reference) 2F051 AA00 AB02 AC07 4K046 HA05 JA09 JD06 JD09 LA06

Claims (6)

[Claims] 1. A method for measuring a fluctuating load in a fluidized bed apparatus having a tube group in a fluidized bed, comprising: forming a hole in a tube wall of a dummy tube simulating an inner layer tube; One end of an object capable of propagation is joined, a pressure sensor is connected to the other end of the object, and the pressure sensor measures the pressure fluctuation due to the collision of the flowing medium propagating from the hole of the dummy pipe through the inside of the dummy pipe. And, based on the measured values,
A method for measuring a fluctuating load of a fluid medium in a fluidized bed apparatus, which is proportional to the pressure fluctuation. 2. An apparatus for measuring a fluctuating load in a fluidized bed apparatus in which a tube group is arranged in a fluidized bed, wherein a dummy tube having a hole in the tube wall is formed by simulating a tube arranged in the fluidized bed. A fluidized bed, which is disposed in a bed, one end of an object capable of transmitting pressure is joined to an end of the dummy pipe, and a variable load analyzer is connected to the other end of the object via a pressure sensor. A device for measuring the variable load in the device. 3. An apparatus for measuring a fluctuating load in a fluidized bed apparatus in which a tube group is arranged in a fluidized bed, wherein a tube arranged in the fluidized bed is imitated, and a tube axis direction of a dummy pipe having both ends opened. The middle of the dummy pipe is divided into two chambers, holes are formed in the wall of the dummy pipe in each chamber, and one end of an object capable of transmitting pressure to both ends of the dummy pipe. Characterized in that a variable load analyzer is connected to the other end of the object via a pressure sensor. 4. The flow according to claim 3, wherein a plurality of dummy tubes having substantially the same length are arranged in parallel in at least one of the width direction, the height direction, and the depth direction in the fluidized bed. A device for measuring the fluctuating load in a layer device. 5. A method for measuring a fluctuating load in a fluidized bed apparatus having a tube group in a fluidized bed according to claim 1, wherein a wear amount of a pipe in the fluidized bed apparatus is measured based on the fluctuating load obtained. how to. 6. A fluctuation measured by the fluctuation load analyzer adjacent to a fluctuation load analyzer of a device for measuring a fluctuation load in a fluidized bed apparatus having a tube group in the fluidized bed according to claim 2 or 3. An apparatus for measuring a wear amount of a pipe in a stratum, wherein a device for analyzing a wear quantity of a stratum pipe in a stratum is provided based on a load.