JPH0225603A - Boiler device and operation thereof - Google Patents

Abstract

PURPOSE:To enable an increasing of water level within a water storage tank to be reduced and further to reduce its capacity during energization of a furnace by a method wherein a fluid passage is provided with a bypassing pipe for bypassing fluid to a gas-water separator and with a valve for opening or closing the bypassing pipe. CONSTITUTION:During a normal operation of a boiler device, a valve 12 arranged in a bypassing pipe 11 is closed. When energized, the valve 12 arranged in the bypassing pipe 11 is opened under an estimation of occurrence of a plugging phenomenon, fluid to be discharged from an outlet 2A of a furnace 2 is flowed to a bypassing pipe 11 having a low, flow resistance and then a ceiling wall 3, a casing wall 4 a flue evaporator 5 are substantially bypassed. Due to this fact, water to flow from the furnace 2 to the gas-water separator 7 is only water left in the furnace 2 and the bypassing pipe 11, resulting in that an amount of water expelled out due to the plugging phenomenon can be restricted. Accordingly, an amount of water discharged from the gas-water separator 7 is reduced and a rapid increasing of water level within the water storage tank 8 is prevented.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a boiler device having a steam-water separator and a method of operating the same, and particularly to a boiler device having a steam-water separator and a method for operating the same. The present invention relates to a boiler device and an operating method suitable for this purpose.

[Conventional technology]

In conventional boiler devices, intermediate load operation is required in thermal power generation due to the recent increase in nuclear power generation and the increasing disparity in power demand between day and night. Therefore, many supercritical pressure variable pressure operation boilers are being operated as boilers suitable for this intermediate load operation. In such a type of boiler that performs variable voltage operation to improve efficiency under partial load, the fluid is fed in a mixed state of steam and water from the time of startup until it enters the superheater during low load operation. Therefore, as shown in FIG.
．． Before passing through the cage wall 4 and the flue evaporator 5 and entering the superheater 6, it passes through a steam-water separator 7 provided upstream of the superheater 6, and is separated from steam and water by the steam-water separator 7. The steam from one side goes into the superheater 6, and the water from the other side goes into the storage tank 8. The water that has entered the water storage tank 8 is then transferred to the furnace 2 by a recirculation pump 9.
recycled within. This water storage tank 8 adjusts the supply of water to a recirculation pump 9 when storing water separated from steam and water and recirculating it into the furnace 2.

When the furnace 2 is started and ignited, the amount of steam generated in the furnace 2 is extremely small, but as the amount of fuel input increases and the temperature of the inlet water supply rises, steam is generated in the furnace 2 in an extremely short time. Since the volume of this steam corresponds to about 50 to 100 times that of water, this increase in volume is rapid and large. As a result, a so-called Proppen phenomenon (bulging phenomenon) occurs, which pushes out a large amount of water flowing into the upper part of the furnace 2, the ceiling wall 3, the cage wall 4, the flue evaporator S, etc. downstream. When this Proppen phenomenon occurs, the water in the fluid path from the furnace 2 to the downstream steam-water separator 7 is pushed out to the steam-water separator 7, and the water level in the water storage tank 8 rises rapidly and then rapidly falls. Therefore, the water level in the water storage tank 8 sometimes exceeds the upper limit, which causes a large disturbance in stably controlling the recirculation flow rate to the furnace 2. In particular, if the control cannot follow up, the recirculation pump 9 will trip, so a sudden rise in the water level in the water storage tank 8 when the Proppen phenomenon occurs is a major hindrance to boiler operation.

As a conventional measure against this Bloppen phenomenon, the capacity of the water storage tank 8 has been increased so that the fluid flowing into the water storage tank 8 during the Bloppen phenomenon does not exceed the upper limit of the water level of the water storage tank 8.

[Problem to be solved by the invention]

In conventional boiler equipment, the Proppen phenomenon occurs when the furnace is started, and a large amount of water swells and flows into the water storage tank. At the same time, the water evaporates instantly in the furnace, which has a high heat load.
Due to the accompanying increase in specific volume, water in the fluid path from the furnace to the downstream steam/moisture vessel is pushed out at once into the water storage tank. As a result, the water level in the water storage tank sometimes rises rapidly, causing problems in boiler operation. Therefore, increasing the capacity of the water storage tank means that the water storage tank is effectively used at high loads when water is not recirculated to the furnace. In order not to
There was a problem that there was a lot of waste in terms of equipment costs.

The purpose of the present invention is to reduce the rise in the water level of the water storage tank,
An object of the present invention is to provide a boiler device and an operating method that can reduce the capacity of a water storage tank.

[Means to solve the problem]

In order to achieve the above object, the boiler device according to the present invention is provided with a fluid path for flowing fluid from the furnace outlet to a steam separator, and one of the steams separated by the steam separator is supplied to the superheater.
In a boiler device that supplies external water to water storage tanks, the fluid path is configured to include a bypass pipe that bypasses the fluid to a steam-water separator, and a valve that opens and closes the bypass pipe. There is.

Further, the method for operating the boiler apparatus includes providing a bypass pipe line for bypassing fluid to a steam-water separator and a valve for opening and closing this bypass pipe line in the fluid path, and opening the valve at the time of startup when the Proppen phenomenon occurs; The fluid is configured to flow through the bypass conduit to suppress the amount of water expansion from the fluid path, thereby preventing a rapid rise in the water level of the water storage tank.

[Effect]

In the boiler device and operating method according to the present invention, by opening the valve of the bypass pipe at the time of startup when the Proppen phenomenon occurs, the fluid at the furnace outlet flows through the bypass pipe with small flow resistance, and the fluid at the furnace outlet flows on the downstream side of the furnace exit. ceiling walls, cage walls in the fluid path of the.

The flue evaporator is effectively bypassed. Therefore, little of the water held during this period is bulged into the steam-water separator, and therefore water does not flow rapidly into the water storage tank.

[Embodiment] An embodiment of the present invention will be described with reference to FIGS. 1 and 2.

As shown in FIG. 1, an economizer 1 connected to a boiler feed pump (not shown) is connected to an inlet 2A of a furnace 2 via a plumber 0A.

An outlet 2B of the furnace 2 is connected to a ceiling wall 3, and the ceiling wall 3 is connected to an inlet 4A at the lower end of the cage wall 4 via a pipe 10B. Further, the outlet 4B at the upper end of the cage wall 4 is connected to the inlet 5A of the flue evaporator 5 via a pipe 10G, and the outlet 5B of the flue evaporator 5 is connected to the steam separator 7 via a pipe 10D. ing. Furthermore, this steam water separator 7 is provided with a pipe 10E for feeding the separated steam to the superheater 6, a pipe 10F for feeding the separated water to the water storage tank 8, and a water storage tank. 8 is connected to the economizer 1 via a recirculation pump 9 and a pipe 10G. The fluid from the outlet 2C of the furnace 2 is transferred to the steam separator 7
A fluid path consisting of the parts and piping that flows through the fluid path,
In a boiler device that supplies one steam separated by a steam/water separator 7 to a superheater 6 and the other water to a water storage tank 8, a bypass pipe line 11 that bypasses fluid to the steam/water separator 7 in a fluid path. This configuration includes a valve 12 for opening and closing the bypass pipe 11.

Next, a method of operating the boiler apparatus constructed as described above will be explained with reference to FIG. 2. The amount of water flowing into the water storage tank 8 due to the Proppen phenomenon differs depending on the fuel used, and the amount of heat absorbed in the furnace 2 is small. Compared to a boiler, the amount of water held in the fluid path from the furnace 2 to the steam-water separator 7 is large, and therefore the amount of water discharged due to the Proppen phenomenon is also large. This gas-fired boiler is shown in FIGS. 1 and 2.

During normal operation after the boiler equipment is started, the valve 12 provided in the bypass pipe 11 is closed.

Water from the boiler water pump is 1 economizer, 10A pipes,
Furnace 2. Ceiling wall 3, piping 10B, cage wall 4, piping 10
It flows into the steam/water separator 7 through the C1 flue evaporator 5 and piping 10D. If you operate this flow path during startup, a Proppen phenomenon will occur.

Furnace 2. It flows into the water storage tank 8 via the ceiling wall 3, the cage wall 4, and the steam/water separator 7 in the flue evaporator 5. Therefore, at startup, by predicting the occurrence of the Proppen phenomenon and opening the valve 12 provided in the bypass pipe 11, the fluid discharged from the outlet 2A of the furnace 2 is directed to the bypass pipe 11, which has a clearly lower flow resistance. The ceiling wall 3, the cage wall 4 and the flue evaporator 5 will be substantially bypassed. Therefore, the water flowing from the furnace 2 to the steam water separator 7 is transferred between the furnace 2 and the bypass pipe 11.
The amount of water bulging out due to the Probben phenomenon can be suppressed.

Therefore, at the time of startup when the Proppen phenomenon occurs, the amount of water discharged from the steam separator 7 to the water storage tank 8 is reduced, and a rapid rise in the water level of the water storage tank 8 is prevented.

Note that flowing the fluid from the furnace 2 through the bypass line 11 into the steam/water separator 7 may result in no or less water flowing into the ceiling wall 3, cage wall 4, and flue evaporator 5; Since the operation to open the bypass pipe 11 is performed at startup when the heat load is small, the metal temperature will not exceed the allowable value due to stagnation of water flow. This is obvious when compared with the situation where no steam is flowing into the heating tube. Also, by predicting the timing at which the Proppen phenomenon occurs and appropriately controlling the timing to open the valve 12.

It is possible to ensure the minimum required amount of water in the bypassed flow path.

According to this embodiment, at the time of startup when the Proppen phenomenon occurs, the amount of water and moisture R1a'l decreases, so a rapid rise in the water level of the water storage tank 8 is suppressed, and the capacity of the water storage tank 8 can be reduced. I can do it. Furthermore, even if a large amount of fuel is injected to shorten the startup time, the amount of water flowing into the steam/water separator 7 can be reduced.

In this embodiment, a case has been described in which the bypass pipe line 11 is connected to the outlet 2C of the furnace 2, but this bypass pipe line 11
may be connected between the ceiling wall 3 and the cage wall 4 or between the cage wall 4 and the flue evaporator 5, as shown in dotted lines in FIG. Further, in order to ensure the inflow of water into the bypass pipe line 11, a valve 13 may be provided in the flow path on the downstream side of the ceiling wall 3, and this valve 13 may be closed during the bypass operation.

〔Effect of the invention〕

According to the present invention, a bypass pipe line and a valve are provided in the flow path from the furnace to the steam-water separator, and by flowing fluid through the bypass pipe line at the time of startup when the Proppen phenomenon occurs, it is possible to It is possible to suppress the expansion amount of water in the water storage tank, suppress a sudden rise in the water level of the water storage tank, and reduce the capacity of the water storage tank.

[Brief explanation of the drawing]

FIG. 1 is a vertical cross-sectional view schematically showing an embodiment of the present invention, and FIG.
The figure is a flowchart showing the operation of this embodiment, and FIG. 3 is a flowchart showing the conventional technique. 2...furnace, 6...superheater, 7...steam water separator,
8... Water storage tank, 11... Bypass pipe line, 12.
··valve.

Claims (1)

[Scope of Claims] 1. A fluid path is provided for flowing fluid from the furnace outlet to a steam/water separator, one of the steam separated by the steam/water separator is sent to the superheater, and the other water is sent to the water storage tank. 1. A boiler device for supplying the respective fluids, wherein the fluid path is provided with a bypass pipe line that bypasses the fluid to the steam water separator, and a valve that opens and closes the bypass pipe line. 2. A bypass pipe line for bypassing the fluid to the steam-water separator and a valve for opening and closing the bypass pipe line are provided in the fluid path, and the valve is opened at the time of startup when the Proppen phenomenon occurs;
A method for operating a boiler apparatus, characterized in that the fluid is distributed through a bypass pipe line to suppress the amount of water bulging out from the fluid path, thereby preventing a rapid rise in the water level of a water storage tank.