JPS59191803A - Boiler - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field 1] The present invention relates to a boiler such as a vertical water tube type natural circulation type boiler.

[Prior Art 1] Examples of conventional boilers of this type are shown in FIGS. 1 and 2. The upper header 1 and the lower header 2 are annular, and a large number of vertical wooden pipes 3 A, 3 B are closely arranged between them to form double water pipe walls 4, 5. The interior of the inner water pipe wall 4 serves as a combustion chamber 20, in which a burner 10 is provided. Inner water 21 is formed. water pipe wall 5
A mantle 6 is provided on the outside of the pipe, and an annular gas passage 22 shaped like J# is formed between the mantle 6 and the water tube wall 5. Openings 7, 8 and a flue 23 are provided for conducting combustion gases from the combustion chamber 20.

In this case, the inner water tube wall 4 receives radiant heat and convective heat from high-temperature combustion gas, and the outer water tube wall 5 receives only convection heat from high-temperature and low-temperature combustion gases, so there is a gap between the two walls. There is a clear difference in the amount of heat received. Therefore, the inner water pipe 3A operates as an evaporation pipe containing a large amount of air bubbles, and the outer water pipe 3B operates as a downcomer pipe containing only a small amount of air bubbles or no air bubbles. Water circulates naturally.

The disadvantage of this case is that the upper header 1 is connected to both the evaporator pipe and the downcomer pipe, forming a -chamber, so the water level measurement error becomes large due to generated bubbles, and the steam room water level does not change due to fluctuations in steam load. In other words, the change in the apparent water level is opposite to the change in the true water level, the controllability of the water supply is poor, and the fluctuation in the water level is large. That is, when the steam load increases, the inner water pipe 3A contains a large amount of steam, so the bubble volume increases and the entire steam chamber water level temporarily becomes extremely overloaded, even though the true water level decreases. On the other hand, when the steam load starts to decrease, the water level measurement error is large and the response is opposite to that of the load.

[Objective of the invention 1] The present invention provides a method for maintaining different water heads.
By connecting the upper ends of the multi-bubble water pipe and the small-bubble water pipe to the respective chambers of an integral upper header whose lower part is separated into two chambers, the above-mentioned drawbacks of the conventional one can be eliminated, and the detection inside the upper header can be improved. It is an object of the present invention to provide a boiler that can perform water supply control with good controllability by stabilizing the water level, reducing measurement errors, and adapting the detected water level to the load.

[Configuration 1 of the Invention] The present invention provides a boiler having a water pipe wall formed by closely arranging a plurality of vertical water pipes whose upper and lower sides are connected to an upper header and a lower header, respectively. The upper pipe header is divided into a multi-bubble water pipe group in which many bubbles are generated and a small-bubble water pipe group in which fewer bubbles are generated, and the upper header is integrally shaped as Y&, and the inside thereof is commonly communicated with the upper l,
The lower part is divided into two chambers by a partition plate, the upper ends of the water pipes of the multi-bubble water pipe group are connected to the -chamber, and the upper ends of the water pipes of the small-bubble water pipe group are connected to the pond chamber. This boiler is characterized by having a water level controller installed in the chamber to which the wood pipes of the group are connected.

(Example 1) To explain the present invention using the drawings as a practical example, in FIGS. 3 and 4, the wood pipes are connected to water pipes 3A of the multi-bubble water pipe group and water pipes 3B of the small-bubble water pipe group, as described below. The upper header 1 is provided with an annular partition plate 9 extending from the bottom to the middle height.The upper header 1 is integrally formed, and its interior is commonly connected at the top. ,] The ζ part is divided into two chambers by a partition plate 9, and the water pipe 3A is
An upper pipe header 24 for water pipes and an upper pipe header 25 for water pipes 3B are formed, and the upper ends of water pipes 3A of the multi-cell water pipe group and the upper ends of the wood pipes 3B of the small-cell wood pipe group are respectively connected. By being partitioned by the partition plate 9, the water pipe 3A
The water level in the header 24, that is, the water head of the water pipe 3A,
This can be done independently of the water level in the upper header 25 for the water pipe 3B, that is, the water head of the water pipe 3B.

A mist separator 19 is provided in the upper part of the upper header 1, and in particular a partial mist separator 18 is provided below the steam outlet 11.

12 is a water level detector 1), upper pipe header 25 for woodwind 3B
communicates with the liquid phase part and the gas phase part through communication passages 26 and 27,
It is equipped with a float 14 and a float magnet contact 15 (single or plural), and is designed to detect the water level at one or more points and emit a signal. Upper pipe header 2 for water pipe 3B
5 has a water supply pump 13 for water supply, a check valve 16,
A stop valve 17 is connected. The flow rate control (on/off, stepwise or continuous control) of the water supply pump 13 is performed based on the signal from the water level detector 12.

During operation, as mentioned above, the group of inner water tubes 3A is a multi-cell water tube group that receives a large amount of heat and generates many bubbles, and the group of outer water tubes 3B receives a small amount of heat and generates few bubbles. This is a low-bubble water pipe group that does not contain any water. Since the liquid phase part of the upper header 1 is divided by the partition plate 9, the hot water in the upper header 24 for the water pipe 3A and the upper header 25 for the water pipe 31B is
In addition to creating a difference in specific gravity based on the bubble content, the pumping action of the rising air bubbles creates a difference in water level and head, resulting in a strong circulation force.

However, in the upper header 24 for water pipe 3A, the liquid level fluctuates rapidly due to air bubbles, but in the upper header 25 for water pipe 3B, there are few air bubbles, so the liquid level is stable, and each time this liquid level is detected, Stable water supply amount control can be performed.

When the steam load increases, the liquid level a for the water tube 3A group with a large bubble content rises as the bubble volume increases rapidly. On the other hand, for water tubes 3B group with a small bubble content, there is almost no increase in the bubble volume, and on the contrary, the liquid level 1] decreases. Conversely, when the steam load decreases, the liquid level a
The liquid level l) suddenly rises by 1°C or 1ζ, or the liquid level l) rises on the contrary.

As shown in Figure 2 below, one liquid level is not easily affected by the disturbance of air bubbles when the load changes, and stable liquid level detection can be performed, and it shows a response that adapts to the steam load, so this liquid level can be removed. By adjusting the water level, ideal water supply amount control is possible.

The water pipe walls 4 and 5 may be not only double-walled but also triple-walled or even double-walled. Further, the upper header for the multi-bubble water pipe group and the two-part header for the small-bubble water pipe group are integrated as in the above embodiment.

[Effect of the invention 1] According to the present invention, a stable water level can be detected even during operation, detection errors are small, and fluctuations in the detected water level adapt to load fluctuations, so highly reliable water supply amount control can be performed. In addition, it is possible to provide a boiler with a compact structure and high thermal efficiency, which is extremely effective in practical terms.

[Brief explanation of the drawing]

@ Figure 1 is a vertical cross-sectional view of the conventional example, Figure 2 is a cross-sectional view taken along the line ■-■, Figure 3 is a vertical cross-sectional view of a part of the embodiment of the present invention, and Figure 4 is a cross-sectional view taken along the line 11-11. It is a diagram. 1--upper header, 2-m-lower header, 3 A,
3 B--water pipe, 4.5-m-water pipe wall, 6--mantle,
7, 8---opening, 9m-partition plate, 10---burner, 1 steam outlet, 12---water level detector, 1
3-m-water pump, 14-m-float, +5---
70-Magnet contact 2 fish 16--Check valve, 17
--- Stop valve, 18° + 9 --- Mist separator, 20
-m-Combustion chamber, 21゜22--Gas passage, 23--One flue, 24-m-Upper header for water pipe 3A, 25-Wood pipe 3
Upper pipe header for B, 2nd day. 271 - A series of passages.

Claims (1)

[Claims] 1. In a boiler having a water pipe wall formed by closely arranging a plurality of vertical wood pipes connected to an upper header and a lower header, respectively, the plurality of vertical The water pipes are divided into a multi-cell wood pipe group that generates many bubbles and a small-cell water pipe group that generates few bubbles. It is divided into two units by a partition plate, and one chamber is connected to the double of the water tubes of the multi-bubble water tube group, and the other chamber is connected to one end of the wooden tube of the small bubble water tube group. A boiler characterized in that a water level controller is provided in a chamber to which water pipes of a water pipe group are connected. 2. The boiler according to claim 1, wherein a plurality of the water pipe walls are arranged concentrically. 3. The multi-bubble water pipe group is composed of a plurality of water pipes forming the water pipe wall relatively near the center, and the low-bubble wood pipe group is composed of a plurality of water pipes forming the water pipe wall relatively outward. Claim 2 consisting of
Boiler described in section.