JPS5922121B2 - Thermal power plant water tank - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a water tank for a thermal power plant, which acts as a mixing heater and a deaerator and has a number of feed water injection nozzle arrangements in the tank.

Such a water tank is based on West German patent application publication No. 12527.
Heated steam introduced below the water surface maintains the feed water at boiling temperature, in which case non-condensable gases, especially oxygen, are expelled from the feed water and into the steam chamber of the feed water tank. The feed water is discharged together with steam.The water is finely sprayed onto the water surface by an injection nozzle, and the heated steam comes into contact with the fine water droplets and condenses, raising the temperature of the water droplets to their saturation temperature.

A portion of the heated steam is discharged from the water tank above the water screen in the area of cold feed water exit from the injection nozzle.

This discharged vent gas-containing vapor causes non-condensable gas to be removed from the water tank. The purpose of directing the vent gas-containing steam through the cold injection water region is to condense some of the water vapor there to reduce steam losses.

In order to perform sufficient deaeration, the West German Patent Application Publication No. 2
312,475, the entire water storage in the water tank must always be flushed with steam.

The heated steam is then sent to a number of perforated tubes via distribution pipes located above the water surface. This perforated pipe is connected almost vertically into the water supply tank and has a hole at its lower end for steam outflow.The heated steam enters the surface-type feedwater heating pipe system located below the water surface. , after which a water supply tank is introduced into a steam room above the water surface, is described in West German Patent No. 1010.
It is known from specification No. 974.

The object of the invention is to have an injection nozzle device in the tank, which acts as a mixing heater and deaerator, without impairing the deaeration action during normal operation and without increasing the withdrawal of vent gas-containing vapors. Another object is to provide a water supply tank in which heated steam is introduced directly above the water surface and distributed at the location of the cool jet of water emerging from the jet nozzle arrangement.

In this way, the material and space requirements required by submerged steam piping are eliminated, and the pressure loss of the heated steam in the flow path, which reduces the efficiency of the steam cycle, is reduced. Accordingly, the present invention provides that at least two water injection nozzle devices with horizontally oriented water jets are arranged side by side in a steam chamber, and that the water generated by the water injection nozzle devices is Relating to a water tank for a thermal power plant, wherein at least one steam inlet pipe opens below the water screen, and at least one steam extraction pipe containing vent gas is connected to a chamber above the water screen. .

The gist of the invention is to protrude at least one vent gas-containing vapor extraction pipe into a water supply tank, and to form an opening for extracting the vent gas-containing vapor by impingement of jet water from mutually adjacent injection nozzle devices. at least one steam inlet pipe is introduced directly above the water surface in the water supply tank, and the steam outlet of this steam inlet pipe is connected to the jet water of the injection nozzle device and the water surface. This is due to the fact that it is located in between.

The vent gas-containing vapor is then discharged via a vent condenser, and the flow rate control of this vent gas-containing vapor is performed in relation to the required degassing characteristics. This non-condensable gas carrier vapor is fully condensed in the vent condenser.
By placing the inlet openings for the vent gas-containing steam close to the collision area of the jet water of the injection nozzle devices adjacent to each other, and also by introducing the heated steam directly into the steam chamber, the water droplets are removed from the point where the vent gas-containing steam is extracted. Since the water droplets are heated to boiling temperature, the gas dissolved in the water droplets becomes separated and reaches ℃. Thus, in the case of the present invention, vent gas-containing steam is extracted at the point where the concentration of non-condensable gases in the steam is highest. Since gas is no longer dissolved in the water droplets at this point,
The fully deaerated feed water is delivered into a reservoir located in the tank. It is therefore no longer necessary to boil this stored water with heated steam constantly introduced below the water surface. The present invention will be described in detail below based on embodiments shown in the drawings.

The feed water is sent to the vent condenser 2 through the water supply inlet pipe 1, and from this point through the pipe 3 to the injection nozzle device 4.

Injection water 29 is ejected from this injection nozzle device 4 in the water supply tank 5 in a nearly horizontal direction. At the location of the impingement area of the water jet 29 there is an opening 6 of a vent gas-containing steam extraction pipe 7 , and the vent gas-containing steam to be discharged is led to the vent condenser 2 through this vent gas-containing steam extraction pipe 7 . Steam used to transport non-condensable gases
The condensate generated at this time is returned to the water tank 5 via the bent water pipe 10. The remaining vent gas goes to pipe 8.
and is discharged via the flow control valve 9. The steam extracted from the turbine is introduced into the distribution pipe 11 from the pipe 28 via the stop valve 23 .

This distribution pipe 11 opens directly into a chamber below the water jet 29 and above the water surface 12 . The deaerated water in the water tank 5 is fed to the water pump 1 via the suction pipe 13.
4, and from this X to the subsequently connected equipment (not shown).

An oxygen metering device 15 connected to a controller 17 is disposed in the water supply suction pipe 13.

In this case, the pulses sent from the water pump 14 to the controller 17 cause the controller 17 to take into account only the measured values which originate from the oxygen measuring device 15 which belongs to the water pump 14 that is in operation. Inside the water tank 5 there is a further oxygen measuring device 16 connected to the controller 17 and measured at °C. Furthermore, the controller 17 receives a height signal of the water level 12 via a measuring line 30. Controller 17
The signal is transmitted to the controller 18.

This controller 18 controls the flow rate control valve 9 when the relationship value between the actual degassing characteristics and the desired degassing characteristics is about to deviate from the allowable range.
change the opening degree. If the flow control valve 9 is already in the fully open position and the degassing characteristics do not correspond to the predetermined value, the valve 20 inserted into the main steam line 27 is opened by the controller 18 and the water level 12 is Steam is conveyed into the water tank 5 by an underlying distribution system 21.

In this case, the valve 19 between the main steam pipe 27 and the turbine bleed steam pipe 28 remains closed. This operating state is considered as an emergency measure, for example, when a large amount of undegassed make-up water is introduced into the water supply tank or when an air intrusion occurs in equipment. Therefore, the distribution piping system 21 may be designed for a considerably smaller amount of steam than is introduced directly above the water surface 12 into the water tank 5 through the distribution piping 11 as turbine bleed steam during normal operation. ℃・. If in operation, for example due to a fault in the power grid, the steam has to be routed by-passing the turbine, the controller 18 receives corresponding pulse signals via the line 22.

This closes stop valve 23 and opens valves 19 and 20. Therefore, in order to prevent an unacceptable drop in temperature and pressure from occurring in the water supply tank 5, the main steam conduit 2 is connected to the water supply tank 5 via a distribution pipe 11 and a distribution pipe system 21.
7 main steam is introduced. At the same time, the flow regulating valve 9 is closed by the controller 18 in order to avoid a pressure drop. In this case, since this step takes a short time, the degassing characteristics will not deteriorate. When starting equipment after a long stop time, a main steam pipe 27 is installed in the portion below the water surface 12 of the water supply tank 5.
, a valve 20 and a distribution pipe system 21, hot steam is introduced.

At this point, the supply water is not introduced or ejected, and the steam contained in the vent gas is extracted via the pipes 7 and 8. Once the desired degassing characteristics are ensured by the oxygen measuring device 16, the main steam introduction is reduced or blocked by closing the controllers 17, 18 and the valve 20. In FIG.
It is shown.

The feed water flows through the pipe 3 in the direction of the arrow 31 into the injection nozzle arrangement 4 . The jet water 29 of the adjacent injection device 4 forms an impingement area 25 , and below the jet water 29 at a location adjacent to this impingement area 25 there is a lower part for discharging the vent gas-containing steam via the vent gas-containing steam extraction pipe 1 . There is an opening 6 of a vent gas-containing steam exhaust pipe 26 that opens toward the vent gas. Heated steam is introduced in the direction of the arrow through the distribution pipe 11,
The heated steam is then introduced through the opening 24 into the cold region of the jet water 29 .

The vent gas-containing steam is discharged in the impingement region 25 so that the vent gas-containing steam is discharged when the non-condensable gas concentration is at its highest, in which case the water droplets have already been heated to the saturated steam temperature in this region. Because of this, the gas does not dissolve into the water droplets again.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of a water supply tank according to the present invention, and FIG. 2 is a cross-sectional view of another embodiment of the injection nozzle device according to the present invention. 1: Water supply introduction pipe, 2: Vent condenser, 3: Piping, 4
: Injection nozzle device, 5: Water supply tank, 6: Opening, 7 Revent gas containing steam extraction pipe, 8: Piping. , 9: Flow rate control valve, 10: Bent water pipe, 11: Steam distribution pipe, 12: Water surface,
13: Suction pipe, 14: Water supply pump, 15, 16: Oxygen measuring device, 17, 18: Controller, 19, 20: Valve, 21:
Distribution pipe system, 22: Piping, 23: Stop and valve, 24: Opening,
25: Collision area, 26: Vent gas containing steam exhaust pipe, 2
7: Main steam pipe, 28: Extraction steam pipe, 29: Injection water, 30
:Measurement line.

Claims (1)

[Scope of Claims] 1. At least two injection nozzle devices with substantially horizontally oriented water jets are arranged in the steam chamber, and a water screen generated by the injection nozzle devices In a water supply tank of a thermal power plant, in which at least one steam inlet pipe is open at the lower side and at least one steam extraction pipe containing vent gas is connected to a chamber above the water screen. , at least one vent gas-containing steam withdrawal pipe projects into the water supply tank, the opening for vent gas-containing steam withdrawal being located close to the impingement area of the jet water of mutually adjacent injection nozzle arrangements; One steam introduction pipe is introduced directly above the water surface in the water supply tank, and the steam outlet of this steam introduction pipe is located between the water jetted by the injection nozzle device and the water surface. A water tank at a thermal power plant. 2. In the water tank described in claim 1,
A water supply tank for a thermal power plant, characterized in that it has steam outlet openings above and below the water surface, and a controller for adjusting residual oxygen concentration opens a valve in a distribution piping system that has a steam outlet opening below the water surface. . 3. In the water tank described in claim 1,
A water supply tank for a thermal power plant, characterized in that an opening of a steam extraction pipe containing vent gas is located directly above a collision area. 4. In the water tank described in claim 1,
A water supply tank for a thermal power plant, characterized in that the opening of the vent gas-containing steam extraction pipe is arranged in a horizontal vent gas-containing steam exhaust pipe that is located below the collision area and opens downward. 5. In the water tank according to claim 2,
Thermal power generation characterized in that a steam introduction pipe with a steam outlet opening below the water surface is designed for a smaller steam flow rate than other steam introduction pipes and is connected to the main steam piping of the thermal power plant. local water tank. 6. In the water tank described in claim 1,
A water supply tank for a thermal power plant, characterized in that a vent condenser is inserted and connected to a vent gas-containing steam extraction pipe outside the water supply tank.