JPH0519780Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a coke level detection device in coke dry extinguishing equipment.

[Conventional technology]

The general structure of the coke dry extinguishing equipment is shown in Figure 4.

In FIG. 4, red-hot coke is charged into a chamber 9 from a coke bucket 7 through a charging hopper 8, and after heat exchanged with an inert gas, is discharged from the system through a gate 10 at the bottom of the chamber. On the other hand, the inert gas that has recovered the sensible heat of the red-hot coke is blown into the lower part of the chamber 9 by the blower 11, exchanges heat with the red-hot coke, generates steam in the boiler 12, and then returns to the blower 11. Circulate inside. Excess gas generated in the system is removed from valve 1.
3, it is appropriately released out of the system.

In such coke dry extinguishing equipment,
The function of detecting the falling amount of red hot coke in the chamber 9 is important for smooth operation of the entire apparatus. However, the chamber 9 is a large-capacity storage tank, and the charged red-hot coke requires measurement under adverse environments such as high temperatures and dust. Therefore, it is difficult to accurately and stably detect the red-hot coke level in the pre-chamber 9. was difficult.

Examples of coke level detection methods and devices include:
There is one shown in Japanese Patent Application Laid-Open No. 160621/1983.
This is done by arranging a plurality of carbon brick blocks B ₁ to _{B o} as one of the electrically conductive objects flush with each other in steps on the inner wall surface _of the pre-chamber 9 shown in FIG. This is a method of determining the level from the resistance change between B _{and o} .

Other known methods include a method of using a light beam and detecting the interruption of the beam, a method of using a radiation beam and detecting the interruption of the beam, and a method of calculating from changes in capacitance.

[Problem that the invention attempts to solve]

However, in the method of determining the level from the resistance change between the carbon brick blocks B ₁ to _{B o} shown in the above-mentioned Japanese Patent Application Laid-Open No. 56-160621, O ₂ enters from the coke bucket 7 shown in FIG. The carbon brick blocks B ₁ to _{B o} are oxidized by the presence of a trace amount of O ₂ in the inert gas that recovers the sensible heat of the coke. Further, due to the sliding action of the coke, the carbon brick blocks B ₁ -B _o wear more quickly than the insulator 4 made of white brick. This makes it difficult to measure the resistance between the carbon brick blocks B ₁ -B _o because the carbon brick blocks B ₁ -B _o become powdered and are lost in a short period of time (approximately one year). In addition, the progress of oxidation of carbon brick blocks B ₁ to _{B o} , and
There was an inherent problem of false detection due to poor contact caused by disturbances such as coke injection and discharge, and
Regarding signal processing, there is no mention of noise removal.

In addition, in the above method ~, measurements are taken under adverse environments such as high temperatures and dust, which requires a large-scale device to protect the measurement window and lens. There are many problems, and in order to improve accuracy, it is necessary to increase the number of installations, which makes it more expensive. In this method, the detection end located inside the pre-chamber is subjected to the sliding action of coke at high temperatures, resulting in malfunctions due to durability issues and coke powder deposited on the detection end.

As described above, all of the conventional detection methods have drawbacks and problems.

[Means for solving problems]

The present invention was developed in view of the above-mentioned situation, and includes a plurality of
A SiC block electrode is attached, and an electrical resistance calculation device is connected to the SiC block electrode via a conductive wire. A coke level detection device in a storage tank, characterized in that it is composed of a differential calculation section that calculates the value of This is what we provide.

Next, the present invention will be explained in detail using figures.

FIG. 1 shows the overall configuration of the present invention, in which a plurality of SiC block electrodes A ₁ to A _o are arranged in steps so as to be flush with the insulator 4 on the inner wall surface of the pre-chamber 9. Attach a lead rod 5 of good conductivity such as SUS with a length up to the outer wall of the pre-chamber to the outer wall of the pre-chamber of the electrodes A ₁ to A _o .
A conducting wire 6 is connected from the lead rod 5 to the electrical resistance calculation device. Coke level is SiC block electrode A ₂
The electrical resistance between the SiC block electrode A ₁ installed at the lowest part and the SiC block electrode A ₂ is several tens of Ω or less, and the other SiC block electrodes A ₃ ~
The electrical resistance value between A _o and SiC block electrode A ₁ is several kΩ.
It has become more than that. This electrical resistance signal is input from the lead rod 5 to the electrical resistance calculation device 1 via a conducting wire 6.

SiC block electrode is SiC: 70-90%, Si: 30
~10%, and its main physical properties are:
Bulk specific gravity 2.90-3.10 (g/cm ² ), porosity 0.82-0.92
(%), bending strength 140 ~ 160 (MPa, at 800℃), linear expansion coefficient 4.4 × 10 ^-6 ~ 4.6 × 10 ^-6 (%), electrical conductivity 0.04 ~
0.06 (Ω・cm, at 800℃).

Next, the electrical resistance calculation device 1 will be explained with reference to FIG.

The electrical resistance calculation device 1 includes a DC (direct current) power supply unit 15 that is supplied between the lowest SiC block electrode A ₁ and the other SiC block electrodes A ₂ to _{A o} arranged in steps as shown in FIG. , an electric resistance calculation unit 16 that calculates the electric resistance signal between the lowest SiC block electrode A ₁ and the other SiC block electrodes A ₂ to A _o into an electric resistance analog signal, and converts the electric resistance analog signal into an electric resistance change signal. Differential calculation section 17 that calculates on the rate signal, setting signal supply section 18 that serves as a coke presence/absence determination standard, coke presence/absence determination section 19, coke presence/absence signal output section 2
The DC power supply section 15, which is comprised of 0.0, supplies a stable DC power supply of more than 10 V between the lowest SiC block electrode _A1 and the other SiC block electrodes _A2 to _Ao . The electrical resistance calculation unit 16 calculates the lowest SiC block electrode _A1 and the other SiC block electrodes _A2 to _Ao.
The electric resistance signal between several ohms and several kohms, mA or
Calculate on mV analog signal. Differential calculation section 17
differentially calculates the degree of change in the electrical resistance analog signal to obtain an electrical resistance change rate signal. This is to prevent false detection due to contact failure caused by disturbances such as coke injection and discharge. Setting signal supply section 1
8, three setting signals are supplied as criteria for determining the presence or absence of coke. (1) Setting signal for coke presence/absence determination criteria for electrical resistance analog signal, (2)
Setting signal for coke presence/absence judgment criteria for electrical resistance change rate signal, (3) Time setting signal for coke presence/absence judgment standard to confirm the continuation of the time when the electrical resistance analog signal and electrical resistance change rate signal are stable in the AND state. There are three. Coke presence/absence determination section 19
compares the electrical resistance analog signal/electrical resistance change rate signal with the coke presence/absence determination reference setting signal to determine the presence or absence of coke. The coke presence/absence signal output section 20 outputs the presence/absence of coke as an ON-OFF signal based on the coke presence/absence determination signal.

Furthermore, the recorder 2 records each calculation signal calculated by the electrical resistance calculation device 1. The coke level display lamp 3 displays the coke level in response to an ON-OFF signal from the electrical resistance calculating device 1 indicating the presence or absence of coke.

[Effect]

The operation of the present invention will be explained in detail below using the time chart shown in FIG.

When the coke level is lower than the SiC block electrode A ₂ shown in Fig. 1, the SiC block electrode A ₁ and the SiC
The electrical resistance analog signal between block electrode _A2 is
It is an analog signal of several kΩ or more. Since the electrical resistance analog signal is stable at several kΩ or more,
The rate of change in electrical resistance is zero, and the determination of the presence or absence of contact failure determines that there is no contact failure. In this state, the electric resistance analog signal is higher than the coke presence determination reference setting signal, so the coke presence determination section determines that there is no coke, and the coke presence signal output is OFF, so the coke level display lamp does not light up.

Coke is added and the coke level is SiC
When it becomes higher than the block electrode _A2 , the electric resistance analog signal between the SiC block electrode _A1 and the SiC block electrode _A2 changes from several kΩ or more to less than a dozen or so Ω. Since the electrical resistance analog signal suddenly changes from more than a few kΩ to less than a dozen Ω, the electrical resistance change rate signal is
It becomes a negative signal from zero. In this state, the electrical resistance change rate signal is outside the signal range set for the coke presence/absence determination standard, so it is determined that there is a poor contact, and the coke presence/absence determination section indicates that there is no coke, and the coke presence/absence signal output is OFF, so the coke level display lamp does not light up. .

When the coke level becomes higher and stable than SiC block electrode A ₂ , SiC block electrode A ₁ and
The electrical resistance analog signal between the SiC block electrode _A2 is stable at less than a dozen ohms. Since the electrical resistance analog signal is stable at less than 10-odd ohms, the electrical resistance change rate is zero. In this state, the electrical resistance analog signal is lower than the set signal for the coke presence/absence determination standard, so the coke presence/absence determining section determines that coke is present, and the electrical resistance change rate signal is within the range of the set signal for the coke presence/absence determination standard, so the coke presence/absence determination is made. The department determined that there was coke. Both the electrical resistance analog signal and the electrical resistance change rate signal are determined to indicate the presence of coke, and the stability duration timer is activated. If the stable continuation time is set to OFF for less than 10 seconds and ON for 10 seconds or more, both the electric resistance analog signal and the electric resistance change rate signal are determined to be coke present, and if the stable continuation time is less than 10 seconds, it is determined that coke is present. The signal output is OFF, but the stable duration time is 10
When it continues for more than seconds, the coke presence signal output is ON.
Then, the coke level indicator lamp for SiC block electrode _A2 lights up.

When coke is added and the coke level rises each time, each SiC block electrode A ₃ ~ _{A o}
The electrical resistance signal between SiC block electrode _A1 is
The coke level indicator lamps for each of the ceramic electrodes A ₃ to _{A o} are turned on by performing the above-mentioned operation while changing sequentially from a few kΩ or more to a dozen or more Ω or less. When coke is discharged and the coke level drops each time, the electrical resistance signal between each SiC block electrode A _o to A ₃ and SiC block electrode A ₁ changes sequentially from less than 10 ohms to more than several k ohms. and each SiC block electrode
The coke level indicator lamps for A ₃ to _{A o} go out.

As mentioned above, in order to improve the accuracy of coke level detection, the distance between SiC block electrodes A ₁ to _{A o} is made small, and the area of contact between SiC block electrodes A ₁ to _{A o} is made smaller than the diameter of the coke lump. It is effective to make it larger.

[Effect of idea]

As explained above, according to the present invention, the life of the block electrode is longer than that of the conventional device, and the reliability of the coke level detection signal is high, making it an extremely effective device for detecting the coke level in a storage tank.

[Brief explanation of the drawing]

FIG. 1 is an overall configuration diagram of the present invention, FIG. 2 is an explanatory diagram of the electrical resistance calculation device of the present invention, FIG. 3 is an explanatory diagram of processing of a coke level signal using the device of the present invention, and FIG. 5 is an overall view of a coke storage tank, and FIG. 5 is a diagram of a conventional coke level detection device. 1... Electrical resistance calculation device, 2... Recorder, 3...
... Coke level display lamp, 4 ... Insulator, 5
...Lead rod, 6...Conducting wire, 7...Coke bucket, 8...Charging hopper, 9...Chamber, 1
0...Gate, 11...Blower, 12...Boiler, 13...Valve, 15...Power supply section, 16...Electric resistance calculation section, 17...Differential calculation section, 18...Setting signal supply section, 19 ...Coke presence/absence determination section, 20
...Coke presence/absence signal output section.

Claims (1)

[Scope of utility model registration request] Multiple SiC
A block electrode is attached, and an electrical resistance calculation device is connected to the block electrode via a conductive wire. A coke level detection device in a storage tank, comprising: a differential calculation section that performs calculations, a setting signal supply section that serves as a criterion for determining the presence or absence of coke, a coke presence determination section, and a coke presence signal output section.