JPS59170601A - 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 The present invention relates to a boiler, and particularly to a boiler suitable for use as an auxiliary boiler mounted on a ship.

Because the marine auxiliary boiler is used infrequently, the boiler efficiency is determined by combusting fuel mainly for driving the main engine, and the combustion gas 3 is heat absorbed in the furnace 1, which is the combustion chamber, and the rear evaporator tube group 4. .

After exchanging heat with canned water, it is discharged from the chimney to the outside of the boiler.

On the other hand, the factors that determine the size of the furnace are to make the burner combustion flame large enough without having to cool it with a water-cooled wall, and to ensure sufficient circulation of canned water. Collision of flames with water-cooled walls reduces combustion efficiency and generates soot and dust.

-Causes carbon oxide generation. In addition, good circulation of canned water increases uniform heat absorption of the combustion flame and gas radiant heat in the furnace and increases the circulation power of canned water.

This is ensured by providing sufficient water head in the evaporation tube.

If there is a concern about this can water circulation, a method such as installing a special downcomer pipe on the back of the furnace evaporation tube 2 to force can water circulation is taken.

While the water-cooled wall of the furnace absorbs the radiant heat of the flames and high-temperature combustion gas, the rear evaporator tube group absorbs heat through convective heat transfer due to contact between the high-temperature gas and the outer surface of the evaporator tubes that make up the evaporator tube group. The rear evaporator pipe connects the steam pipe and the water pipe. The can water circulation force of this evaporator tube group is also affected by the water head difference and heat absorption ht, but when the water head difference is increased (that is, when the pipe length is lengthened), the solid fI frequency of the pipes becomes low F, which causes hull vibration and PlL1 beller excitation. There is a concern that it may resonate with the vibration frequency. Furthermore, the layout of the combustion air tact and the air gas tact have a large effect on the layout of the boiler inside the ship.

In view of the above, the present invention aims to provide a boiler that satisfies the requirements (1) to (8) below.

(1) The size of the boiler compared to the boiler a1M is reduced to make it easier to arrange it inside the ship.

(2) Reduce the number of equipment equipment (reduce the number of burners) and simplify automation.

(3) Design the combustion chamber according to the length of the burner flame to prevent the flame from coming into contact with the water-cooled wall, thereby preventing the generation of soot, unburned carbon, carbon oxide, etc. (Recent cylindrical boilers (In many cases, it may not be possible to ensure a sufficient flame length.)

(4) Improve the waste flow and maximize the FI efficiency of the contact heat transfer surface.

(5) Easy placement of air ducts and gas ducts.

It also simplifies the layout inside the ship.

(6) Vessel vibration: Avoid resonance with single-peller excitation vibration.

Simplify anti-vibration measures.

(7) In preparation for heating the mounting area, extracting inert gas, etc.

It shall have a drum which can be equipped with a pressure holding device to enable rapid start-up.

(8) For the contact heat transfer surface, a finned tube that does not cause gas passage blockage or excessive draft loss can be used (bare tubes can of course be used).

That is, the gist of the present invention is to provide a group of evaporation tubes that communicates a steam drum and a water drum arranged in "-F".

It is equipped with a screen wall tube that separates the evaporator tube group from the combustion chamber, a burner attached to the ceiling of the combustion chamber, and a baffle plate attached to the 7A tube group.

The boiler is characterized in that gas passages are formed in the upper and lower parts of the screen wall tube and a part of the ceiling tube.

And 1, this invention is structured as shown in 1↑2, so it's a good idea!・It is possible to obtain a boiler that can save installation space and production costs.

An embodiment of the present invention will be described below with reference to FIGS. 2 and 3.

The illustrated boiler has a steam drum 11. It is a two-body water tube type having a water drum 12, a combustion chamber (furnace) 13 and an evaporation tube group 14.
It is composed of The combustion chamber and the evaporator tube group are separated by a screen wall tube 15, and the screen wall tube is connected to the boiler outlet [1 tube 16].

Water-cooled wall tube 17. and a screen tube 18, arranged between the steam drum and the water drum.

A single burner 19 is installed on the ceiling of the combustion chamber.

The height of the combustion chamber shall be compatible with the burner flame length.

The evaporator tube group is divided into two by a baffle plate 27 consisting of a comb plate 20 and a refractory material 21, and the high-temperature gas from the combustion chamber outlet flows to the water drum side, and the high temperature gas from the water drum side flows to the steam drum side. The structure should allow low-temperature gas to pass through. A soot blower 22 is installed in each passage as a soot removal device.

The boiler gas outlet section is provided between the ceiling of the combustion chamber and the steam drum, and is composed of a boiler outlet tube 16 which is a screen wall tube and a stack tube 24 formed by a portion 23 of a ceiling tube. The stack part has a gas-sealed structure completely separated from the combustion chamber by the refractory material 25.

Furthermore, not only bare tubes but also finned tubes can be used for the evaporation tube group.

In the boiler described above, the high-temperature gas generated by the burner placed in the ceiling flows as a swirling flow as shown by arrow 26 in Figure 2, effectively exchanges heat within the boiler, and is discharged to the outside of the boiler. Ru. That is, since the combustion chamber has sufficient dimensions for the burner combustion flame, the fuel is completely combusted and the radiant heat is effectively absorbed into the furnace heat transfer surface.

In addition, by dividing the evaporator tube group into two with a baffle plate and allowing the combustion gas to flow, the dead 5 pace of the evaporator tube heat transfer area can be reduced to 7. It is possible to utilize all heat transfer surfaces for Y1 effect.

According to this embodiment, the following effects can be obtained.

(1) With this structure, it is possible to create a swirling flow of the boiler combustion gas, and the contact heat transfer surface (evaporator tube group) can be used effectively, making it possible to make the boiler more compact.

(2) This boiler structure employs ceiling firing and a single burner system. Match the burner flame length.

Combustion chamber height can be determined.

(3) Since the boiler is a ceiling-fired burner, the installation area of the boiler is small, making it advantageous to place it inside a ship.

(4) During Otsuki firing--Due to the burner, the height of the boiler increases, or this improves the water circulation performance per can.

(5) As the height of the boiler increases, the length of the evaporation tube also becomes longer, which lowers the natural frequency of the tube, which raises the issue of resonance with the ship's vibration, but in a two-boiler structure.

To equip a baffle plate in the center of the evaporation tube.

This baffle plate can also be used as an anti-vibration plate for the evaporator tube, and no new anti-vibration measures are required.

(6) Burner control and maintenance can be simplified due to the burner method.

(7) By utilizing the efficiency of the heat transfer area, the efficiency is approximately 2 to 4% higher than that of conventional auxiliary boilers.

[Brief explanation of the drawing]

FIG. 1 is a side view of a conventional boiler, FIG. 2 is a side view showing an embodiment of the present invention, and FIG. 3 is a view taken along the line A--A in FIG. 11 - steam drum, 12 - water drum, 13 - combustion chamber. 14 Evaporation tube group, 15 Screen wall tube, 1
9. Burner, 23. Ceiling tube, 27. Powerful board. Figure 1 Figure 3V Figure 2

Claims (1)

[Claims] An evaporator tube group that communicates the steam tram and the water drum arranged in the upper F1, a screen wall tube that partitions the evaporator tube group and the combustion chamber, and a burner attached to the ceiling of the combustion chamber;
1. A boiler comprising a baffle plate attached to an evaporator tube group, and a waste passage is formed in the upper and lower parts of the screen wall tube and a part of the top:j1 tube.