RU2703144C1 - Device for cooling steam volume of drum between water level and bubbling-flushing device - Google Patents

Abstract

FIELD: heat power engineering.

SUBSTANCE: invention relates to heat engineering and can be used for steam dampening of external sources of boiler drums at variable operating conditions of boilers (at stops, unloading etc.). Proposed plant comprises device for steam cooling of external sources at boiler shutdowns, steam volume of drum above water level and to mark of bubbling-flushing devices with separation devices in form of turbo-steam separator (2), bubbling-flushing devices (5) with drain boxes (6), comprising two distribution manifolds (12) connected to the line for supply of steam of external sources. These collectors (12) are located above drain boxes (6) of bubbling-flushing devices (5), and steam through guide pipes (13), passed through holes cut in corresponding blind sheets (14) between drain boxes, is supplied into space between drain boxes (6), which reduces the distance between the flowing jet and the drum body to 0.05 D_b, where D_b is diameter of drum. Note here that guide branch pipes (13) outlet holes are installed at the middle of steam height so that their axis is located at angle of 15° to the drum axis, due to which the steam streams flowing from them are able to penetrate into the space behind drain boxes (6), which increases the metal cooling intensity and excludes the zones not cooled by the steam.

EFFECT: provision for more intensive cooling of metal of drum walls in its middle part and exclusion of zones not cooled by steam in order to increase reliability of drums.

1 cl, 6 dwg

Description

The invention relates to the field of power engineering and can be used for steam damping of neighboring boiler drums in variable operating modes of boilers (during shutdowns, unloading, etc.).

State of the art

It is known that a device for steam cooling steam adjacent boilers of drums, consisting of 2 distribution manifolds in the steam volume of the drum, located in front of the holey steam receiving device, and 2 collectors located in the water volume of the drum [1].

The disadvantage of this device is the poor cooling of the steam volume of the drum above the water level to a bubbler-flushing device (BPU).

Known adopted as a prototype of the claimed invention, a device for steam cooling of a boiler drum with separation devices in the form of a throttle ceiling, bubbler washing and cyclones containing distribution manifolds with nozzles, one of which is located in the upper part of the steam volume, the other in the lower part of the water volume [RU 2059922 F22B 37/22 1995.01 [2].

Description of the work of the prototype

A device for cooling a boiler drum with steam with separation devices made in the form of a throttle ceiling, sheets of bubbler washing, drainage boxes for washing water from bubblers and cyclones with pallets, contains distribution manifolds located at least two in the upper part of the steam volume under the throttle ceiling, in the lower part of the steam volume under the bubbler sheets, in the lower part of the water volume under the cyclones. Distribution manifolds are equipped with guide pipes with a steam outlet angle of 45 ° <α <90 ° to the longitudinal axis of the drum, and steam from an external source is supplied through steam supply lines.

To cool the boiler drum after it has been stopped, saturated steam is supplied through the steam supply lines from the drums of neighboring working boilers to all distribution manifolds. Through the openings of the guide pipes, steam flows into the wall region of the drum, where heat is exchanged between the wall of the drum and the steam.

The steam supply through two collectors makes it possible to bring the steam jets closer to the wall, direct the steam flow in one direction and reduce the pitch between the guide pipes by about 2 times while maintaining the diameter of the distribution manifold. The step between the nozzles is reduced from 1.5 to 0.5-0.75 m, which allows more even cooling of the wall.

The use of two collectors allows you to organize the total steam flow in each half of the drum in different directions, while a closed steam movement is formed, which allows you to intensively include the boiler’s own steam in the heat exchange along with extraneous.

Thus, the installation of two collectors allows you to more intensively and evenly cool the walls of the drum, and also make the device more compact.

The disadvantage of this technical solution is the low efficiency of the distribution manifolds located under the bubbler-flushing device, since the steam to the central part of the drum through the guide pipes can only reach a length between the drain boxes, which, for example, for the TPE-223 boiler, is approximately 44% of the drum length, and 56% are drain boxes. In addition, due to the fact that the angle of steam exit from the holes of the guide tubes is 45 ° <α <90 ° to the axis of the drum, steam jets poorly penetrate into the space behind the drain boxes. For this reason, sections of the drum behind the drain boxes are practically not cooled.

Disclosure of invention

The objective of the invention is to increase the maneuverability of boilers under variable operating conditions (during shutdown, unloading, etc.), achieved by increasing the cooling efficiency of the section of the boiler drums between the water level and the mark of sheets of the bubbler-flushing device equal to approximately 450 mm The technical result of the invention is to provide more intensive cooling of the metal walls of the drum in its middle part and the exclusion of areas not cooled by steam in order to increase the reliability of the drums. The solution of this problem and the achievement of the specified technical result is ensured by the fact that a device for cooling third-party sources with steam when the boiler stops the steam volume of the drum above the water level and up to the marking of bubbler-flushing devices with separation devices in the form of intra-drum cyclones, bubbler-flushing devices is placed in the boiler drum with drain boxes, containing two distribution manifolds, while according to the invention, these collectors are located above the drain boxes mixtures of bubbler-flushing devices, and steam through guide pipes passed through holes cut in the corresponding blank sheets between the drain boxes is fed into the space between the drain boxes, which allows to reduce the distance between the effluent stream and the drum body to 80 mm (0.05 D _b ) where D _b - the diameter of the drum. In this case, the outlet openings of the guide tubes are installed at the middle of the steam height so that their axis is located at an angle of 15 ° to the axis of the drum, due to which steam streams emanating from them are able to penetrate into the space behind the drain boxes, which allows increasing the cooling rate of the metal and eliminating zones not steam cooled.

Brief Description of the Drawings

In the drawing of FIG. 1 shows a cross section of a drum with steam cooling devices. In FIG. 2 shows a longitudinal section through the drum A-A and B-B. In FIG. 3 shows a longitudinal section of the drum according to G-D. In FIG. 4 shows a guide pipe, FIG. 5 shows a section along DD and the direction of flow of steam jets from the nozzles, in FIG. 6 shows a local view of the location of the cooldown collector and guide pipe.

Designations:

1. Drum

2. Drum cyclone

3. Pallet

4. Cyclone cap

5. Bubbling and flushing device

6. Drain boxes

7. Nutritious water supply box

8. Drain box of feed water

9. Hole steam sheet

10. Established distribution manifolds

11. Fittings

12. Distribution Manifold

13. Guide tubes

14. Blank sheets

15. Pipes for supplying a steam-water mixture.

DETAILED DESCRIPTION OF THE INVENTION

The intra-drum separation devices shown in FIG. 1 contain intra-drum cyclones 2 with pallets 3 and nozzles for supplying steam-water mixture 15, a bubbler-flushing device 5, a drain box 6, a holey steam receiving sheet 9. In addition, in FIG. 1 shows the standard distribution manifolds 10 with fittings 11.

Two distribution manifolds 12 are installed above the drain boxes, with guide pipes 13, which are inserted into the steam volume of the drum space between the drain boxes. For this purpose, in the blank sheets 14 between the drain boxes, holes are cut 5 mm larger than the diameter of the fitting. The fittings have exhaust holes ∅ 4-6 mm, the axes of which are located at an angle of 15 ° to the axis of the drum. In addition, for more uniform cooling of the drum, the fittings are introduced between the boxes to the middle of the height of the steam volume, i.e. 225 mm above the water level in the drum. Distribution manifolds are located approximately 20 mm above the water level on the sheets of the bubbler-flushing device, to prevent narrowing of the inlet sections of the drain boxes.

Description of the operation of the drum cooling device

A device for cooling the steam volume of the drum between the water level and the bubbler-flushing device operates as follows.

Steam for cooling the upper part of the steam volume and the lower part below the water level is supplied through standard distribution manifolds. Steam for cooling the drum above the water level and up to the level of the bubbler washing device is supplied through two distribution manifolds connected to the steam supply line of third-party sources. Steam through the guide pipes enters the space between the drain boxes. Due to the fact that the steam outlet openings of the nozzles are located at a distance equal to 80 mm from the drum body, intensive cooling by the metal vapor of the middle part of the drum occurs. In addition, due to the fact that the nozzles are so long that the steam outlet is located in the middle of the height of the vapor volume (approximately 225 mm), resulting in uniform cooling of the entire drum wall in height. Due to the location of the guide pipes near the body of the drum and the outflow of steam jets at an angle of 15 ° to the axis of the drum, favorable conditions are created for cooling the body of the drum behind the drain boxes due to the movement of steam through the channels behind the drain boxes. All this taken together leads to the fact that there is intensive cooling by jets of steam of the entire metal of the drum between the water level and the BPU sheets, to exclude zones not cooled by steam.

Industrial applicability

A device for cooling the vapor volume of a drum between a water level and a bubbler washing device according to the patented invention meets the condition of "industrial applicability". The essence of the technical solution is disclosed in the formula, description and drawing clearly enough for understanding and industrial implementation by appropriate specialists based on the current state of the art in the field of heat power engineering.

List of sources

1. RD 34.26.517-96. Typical instructions for shutting down a drum boiler using accelerated cooling devices. - M .: SPO ORGRES, 1997

2. Patent 2059922. A device for steam cooling of a boiler drum / N.A. Nikiforov; Applicant and patent holder Open Joint Stock Company for the adjustment, improvement of technology and operation of power plants and networks of Uraltehenergo // decl. No. 9393057469, publ. 12/28/1993.

Claims (1)

A device for steam cooling of external sources during boiler shutdowns, the steam volume of the drum is higher than the water level and up to the marking of bubbler-flushing devices with separation devices in the form of internal drum cyclones, bubbler-flushing devices with drain boxes, containing two distribution manifolds connected to the supply line of third-party steam sources, characterized in that these collectors are located above the drain boxes of bubbler-flushing devices, and steam is passed through the guide pipes data through openings cut in the corresponding blank sheets between the drain boxes is fed into the space between the drain boxes, which reduces the distance between the effluent stream and the drum body to 0.05 D _b , where D _b is the diameter of the drum; at the same time, the outlet openings of the guide tubes are installed at the middle of the steam height so that their axis is located at an angle of 15 ° to the axis of the drum, due to which steam streams emanating from them are able to penetrate into the space behind the drain boxes, which allows increasing the cooling rate of the metal and eliminating zones not steam cooled.

Images