JPH0749208Y2 - Boiler concentrating blow device - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention relates to a concentrating blow device for blowing concentrated boiler water from a boiler.

[Conventional technology]

As is well known, when the boiler is operated for a long time, the can water is concentrated and the dryness of the steam is lowered due to a carryover phenomenon or the like, so it is necessary to replace the can water appropriately. Blow work for that purpose has conventionally been performed by a skilled manager based on many years of experience, but it was a complicated work.

Also, during boiler operation, in order to prevent corrosion in the can,
Injecting a corrosion inhibitor into can water to adjust the pH to an appropriate value (about 10-12)
However, when the boiler is started after the can water is replaced, since the can water is new water, the pH of the can water is low (about 7) and it is very corrosive. Therefore, if the can water is changed too often, the time in which the inside of the can is easily corroded becomes long, which is not preferable. When starting after replacement of canned water, in order to accelerate the rise of pH of the canned water, about 3 times the normal amount of corrosion inhibitor is injected, but if the canned water is replaced frequently, Will also increase usage.

[Problems to be solved by the device]

An object of the present invention is to provide a concentrating blow device for a boiler, which can perform an appropriate concentrating blow operation with a simple structure.

[Means for Solving the Problems]

This invention was made in view of the above problems,
It is equipped with a plurality of water level detection rods with different heights at the detection end, and a concentration blow line with an opening / closing valve for concentration blow inserted. A blower flow rate per unit time calculated from the time during which the water level falls between the detection ends of the plurality of water level detection rods during blowing, which is equipped with a determiner that determines the blow timing using one or more of these elements as the determination conditions. Based on the above, a concentration blow controller for instructing the opening operation of the concentration blow opening / closing valve for a predetermined time is provided.

[Action]

According to the above configuration, the blow timing is determined based on the combustion time of the boiler, etc., and when the predetermined blow timing is reached, the concentration blow opening / closing valve is opened to discharge the required amount of canned water. Based on the signals from a plurality of water level detection rods with different values, calculate the blow flow rate per unit time from the time when the water level falls between the detection ends, and based on this value, the concentration blow on / off valve is operated for a predetermined time. After opening and discharging a predetermined amount, the concentration blow opening / closing valve is closed to perform proper concentration blow.

〔Example〕

A preferred embodiment of the present invention will be described below with reference to the drawings.

The boiler (1) comprises a heating burner (2) and a blower (3) for supplying combustion air to the burner (2). A fuel supply line (4) is connected to the burner (2), and a fuel pump (5) and a fuel solenoid valve (6) are inserted in the fuel supply line (4). Further, the burner (2) is provided with a flame detector (7).

The operation and stop of the boiler (1) are usually controlled according to the load condition, and specifically, the combustion controller (9) is based on the signal of the pressure detector (8) that detects the boiler can internal pressure. Controlled by. That is, the fuel is stopped when the internal pressure of the can exceeds a preset pressure value, and the combustion is started when the internal pressure falls below the preset pressure value.

The boiler (1) is equipped with a water level detector (10) for detecting the water level in the can, and this water level detector (10) has a plurality of water level detection rods (S) with different heights at the detection ends. , (L) are provided (see FIG. 2). The water level detector (10) is ON, O
A signal of FF is emitted, and the water supply pump (12) in the water supply line (11) is turned on and off through an appropriate water level control device to work to keep the water level in the can at a constant level. For example, when the water level in the can cuts off the detection end of the water level detection rod (S) and the set time has elapsed, the water supply pump (12) operates and the water level reaches the detection end of the water level detection rod (S) and the set time is reached. After a lapse of time, the water supply pump (12) is stopped. If the water level does not rise to the detection end of the water level detection rod (L) before the set time elapses after cutting the detection end of the water level detection rod (L), it is determined that there is a failure in the water supply system, In this case, there is a danger of emptying, so an alarm is issued and combustion of the boiler is stopped.

The determiner (13) determines the blow timing based on the concentration of the can water. As the determination element of the blow timing, the amount of water held in the boiler, the amount of evaporation, the combustion time, etc. can be used. For example, the determination can be made by whether or not the combustion time has passed a preset time. To do. In this case, an expensive electric conductivity sensor becomes unnecessary.

To the lower part (lower header) of the boiler (1) is connected a concentration blow line (14) in which a concentration blow on-off valve (15) is inserted, and the concentration blow on-off valve (15) is opened and closed. By doing so, concentration blow is performed. The concentration blow opening / closing valve (15) is controlled by a concentration blow controller (16).
Further, a can bottom blow valve (17) is provided at the bottom of the boiler (1).

For the sake of safety, it is desirable to perform the blowing operation when combustion is stopped and the pressure inside the can is low (for example, about 1 kg / cm ² G or less). When the discharge of the can water is started, the water level in the can drops, and after the detection end of the water level detection rod (S) is cut off, the detection end of the water level detection rod (L) is cut off. ) And the detection end of the water level detection rod (L), the amount of can water discharged is constant. Therefore, by measuring the time, it is possible to accurately know the blow flow rate (blow speed) per unit time regardless of whether the can pressure is high or low, and based on this value, the concentrated blow on-off valve for a predetermined time. When the valve (15) is opened, a desired amount of canned water is discharged to the outside (see FIG. 3). The opening / closing operation of the concentration blow opening / closing valve (15) can be automated by the output signal of the concentration blow controller (16), but can also be performed manually.

The water level is from the detection end of the water level detection rod (S) to the water level detection rod (L)
When the time to fall to the detection end of is longer than the preset time, the concentration blow line (14) may be clogged, the concentration blow on / off valve (15) may be broken, etc. An alarm is issued and blow operation is stopped.

By instructing the opening time of the concentrated blow on-off valve (15) based on the calculated blow flow rate per unit time,
It is possible to accurately and surely grasp and manage the blow amount. Therefore, when discharging canned water, it is easy to discharge about half (about 30 to 70%) of canned water (amount of retained water) without discharging the whole amount. As a result, water having a high pH value remains in the can, and even if fresh water having a low pH value is supplied when the boiler is restarted, the degree of decrease in the pH of the entire can water becomes small. In this way, performing a blowing operation of about half the amount of can water can always maintain the pH of the whole can water within an appropriate range and keep the inside of the can in a state where corrosion is unlikely to occur. It is very effective in operation management. Further, by discharging about half of the can water, the impurities and dust accumulated at the bottom of the can can be sufficiently discharged, and the amount of water used and the amount of corrosion inhibitor used can be saved.

In the illustrated embodiment, two water level detecting rods are provided, but the present invention can also be applied to a boiler having three or more water level detecting rods.

[Effect of device]

Since the present invention has the above-mentioned configuration, the concentration blow work can be performed without a special sensor.
The following practical effects can be obtained.

(1) Accurately and reliably grasp and manage the blow amount regardless of the pressure inside the can by indicating the opening time of the concentrated blow on-off valve based on the calculated blow flow rate per unit time. You can

(2) The operation of discharging about half the amount of canned water (in the range of about 30 to 70%) becomes easy. By performing this operation, not all of the canned water is discharged, so the amount of water used is saved. can do. Also, impurities and dust accumulated on the bottom of the can can be discharged together. In addition, when restarting after blowing, the degree of decrease in the pH of the entire can water is reduced, and there is no need to perform large-scale injection (initial injection) of the corrosion inhibitor, which is conventionally used, and the amount of corrosion inhibitor used is reduced. be able to.

[Brief description of drawings]

FIG. 1 is a system diagram showing an embodiment of the present invention, FIG. 2 is an enlarged vertical sectional view showing an essential part of the present invention, and FIG. 3 shows a relation between internal pressure of a can and concentration blow time. It is a graph shown. (1) …… Boiler, (13) …… Judgment device (14) …… Concentration blow line, (15) …… Concentration blow on-off valve (16) …… Concentration blow controller, (S), (L) ...... Water level detection rod

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yoshimin Tsubota 7 Horie-cho, Matsuyama-shi, Ehime Prefecture Miura Kogyo Co., Ltd. (72) Inventor Hitoshi Sugano 7 Horie-cho, Matsuyama-shi, Ehime Pref. Miura Kogyo Co., Ltd. (72 ) Hideo Ando, 7 Horie-cho, Matsuyama-shi, Ehime, Miura Kogyo Co., Ltd. (72) Kei Shigematsu, 7 Horie-cho, Matsuyama-shi, Ehime, Miura Kogyo Co., Ltd. Eisuke Kiyota (56) References 58-200904 (JP, A) Actual Kaihei 1-169902 (JP, U)

Claims (1)

[Scope of utility model registration request] 1. A concentration blow line (14) having a plurality of water level detection rods (S), (L) with different heights of detection ends, and a concentration blow opening / closing valve (15). The blower has a judging device (13) for judging the blow timing by using one or more of the respective factors such as the amount of water held in the boiler, the amount of evaporation, the combustion time, etc. Concentration for instructing the opening operation of the concentration blow on-off valve (15) for a predetermined time based on the blow flow rate per unit time calculated from the time when the water level falls between the detection ends of the detection rods (S) and (L) A concentrated blow device for a boiler, comprising a blow controller (16).