JPS636761B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides an easy-to-clean system in which a partition cylinder having combustion gas passage ports is rotatably provided between a large number of inner vertical water pipes and outer vertical water pipes arranged in an annular manner. This relates to vertical water tube boilers such as multi-tubular small once-through boilers.

In vertical water tube boilers such as conventional small multi-tube once-through boilers, it is difficult to clean the heat transfer surface, that is, the surface of the water tubes. This point will be explained below with reference to the drawings. FIG. 1 is a horizontal cross-sectional view (taken along the line B--B in FIG. 2) passing through the center of the cleaning lid of a conventional vertical water tube boiler, and FIG. 2 is a cross-sectional view taken along the line A--A in FIG. 1. In the drawing,
1 is an upper header, and 2 is a lower header. 3 is an inner vertical water pipe, and 4 is an outer vertical water pipe. A large number of inner vertical water pipes 3 and a large number of outer vertical water pipes 4 are arranged concentrically in an annular manner between the upper header 1 and the lower header 2, and each of the inner and outer vertical water pipes 3 and 4
Both ends thereof are open to upper and lower headers 1 and 2, respectively. 5' is a heat transfer fin which extends between adjacent inner vertical water pipes 3 other than between predetermined adjacent inner vertical water pipes 3-1 and 3-2, up to the upper and lower headers 1 and 2. The heat transfer fins 5' and the inner vertical water tubes 3 form an annular wall around the center of the vertical water tube boiler to form an upper combustion chamber 6, and the inner vertical water tubes 3-1 and 3-2 constitutes a combustion gas passage port 7' therebetween. Reference numeral 8 denotes a shrouding plate, which is provided outside the outer vertical water pipe 4 and forms a combustion gas passage 9 between the inner vertical water pipe 3 and the heat transfer fin 5'. It will be located inside the gas passage 9. The outside of the shroud 8 is covered with a heat insulating material 10. 11 is a lower combustion chamber provided inside and below the lower header 2, and 12 is a combustion machine. 1
3 is a flue which guides combustion gas to a chimney 14. 1
Reference numeral 5 denotes a steam or hot water outlet pipe, which is provided in the upper header 1. 16 is an upper cleaning port provided above the upper combustion chamber 6;
Removable upper cleaning palate lined with 8 1
It is sealed with 7. Reference numeral 19 indicates lower cleaning openings, which are located at 3 to 4 locations on the lower peripheral surface of the shroud plate 8 (4 locations in the drawing).
Each lower cleaning opening 1
9 is sealed with a removable lower cleaning opening lid 20 lined with a heat insulating material 18. The vertical water tube boiler described above operates as follows. While the upper and lower headers 1 and 2 and the inner and outer vertical water pipes 3 and 4 are filled with water, the fuel supplied from the combustor 12 is first combusted in the lower combustion chamber 11.
After heating the heat transfer surface of the inner vertical water pipe 3 while rising and completing combustion in the upper combustion chamber 6, the combustion gas passes through the combustion gas passage port 7' and flows through the combustion gas passage 9, dividing into left and right sides. The heat transfer surface of the outer vertical water pipe 4 is heated, and a part of the heat transfer surface of the inner vertical water pipe 3 is also heated, and a part of the heat of the combustion gas is transferred to the inner vertical water pipe 3 by the heat transfer fin 5'. Heat is transferred. The combustion gas that has finished its heating action passes through the flue 13 and reaches the chimney 14.
The generated steam or hot water is taken out from the take-out pipe 15 and used for a predetermined purpose. However, as the fuel is burned in this way, soot and the like adhere to the heat transfer surfaces of the vertical water pipes 3 and 4 inside and outside, impairing heat transfer from the combustion gas and severely reducing thermal efficiency. Therefore, it is necessary to clean the inside of the boiler at an appropriate time to remove soot, etc. By the way, cleaning of the conventional vertical water tube boiler having the above structure has been carried out as follows. First, the heat transfer surfaces of the inner vertical water tube 3 and the heat transfer fins 5' facing the upper combustion chamber 6 can be thoroughly cleaned with a cleaning tool such as a wire brush by removing the upper cleaning port 17 and there is no problem. Next, to clean the heat transfer surfaces such as the outer vertical water pipe 4 in the combustion gas passage 9 and the inner vertical water pipe 3 facing the combustion gas passage 9, remove the lower cleaning opening cover 20 and insert a wire brush or the like through the lower cleaning opening 19. However, due to the small number of lower cleaning ports 19 and the small size ratio to the combustion gas passage 9, the outer vertical water pipe 4 and the inner vertical water pipe cannot be reached even if a wire brush or the like is inserted through the lower cleaning port 19. It is extremely difficult to clean the heat transfer surface of 3. Increasing the number or size of the lower cleaning ports 19 not only increases the cost of the device, but also requires a lot of manpower and time for removing and installing them, which is impractical.
The number and size (ratio to the overall dimensions of the boiler) shown in FIGS. 1 and 2 are almost the limits. Therefore, the range that can be cleaned is limited to the range that the cleaning tools can reach, and since that is a part of the heat transfer surface facing the combustion gas passage 9, it is necessary to use the cleaning tools with reduced heat transfer efficiency. It was. In order to eliminate these drawbacks of the conventional vertical water tube boiler, holes for water washing are bored at various places in the heat transfer fin 5', and a water washing tool using tap water pressure is inserted into these holes from the upper combustion chamber 6 side. A method of inserting and cleaning is being tried.
However, when using this method, making the holes larger or increasing the number of holes in order to perform sufficient cleaning results in a large amount of short-circuiting of the combustion gas, so there is a limit to this method.Practically speaking, the output is about 600,000 Kcal/hour. A vertical water tube boiler of this size has approximately 10 holes with a diameter of about 10 mm, but with such a large number of holes, it was not possible to clean them sufficiently even with pressure water.

As a result of research aimed at providing a vertical water tube boiler that is easy to clean and inexpensive, the inventor found that the combustion gas passage port for connecting the combustion chamber and the combustion gas passage can be moved around the combustion chamber. The present invention was completed by discovering that the object can be achieved by doing the following.

That is, in the present invention, a large number of inner vertical water pipes and a large number of outer vertical water pipes are arranged in an annular manner between an upper header and a lower header, and the combustion gas first heats the inner vertical water pipes and then passes through the combustion gas. In a vertical water tube boiler having a passage for combustion gas passing through the mouth to heat the outer vertical water pipe and then being discharged, a partition cylinder having the combustion gas passage port is rotatable between the inner vertical water pipe and the outer vertical water pipe. The present invention relates to a vertical water tube boiler characterized in that it is installed in a vertical water tube boiler. The present invention will be explained in detail below with reference to drawings showing embodiments of a vertical water tube boiler according to the present invention.

FIG. 3 shows a passage through the center of the vertical water tube group of one embodiment of the vertical water tube boiler according to the present invention (D-D in FIG. 4).
4 is a sectional view taken along line C-C in FIG. 3, FIG. 5 is an explanatory diagram showing a cleaning state, and FIG. 6 is a horizontal sectional view corresponding to FIG. 3 of another embodiment. , FIG. 7 is a perspective view of a partition cylinder showing another embodiment in which only the combustion gas passage port is provided.

In the drawing, 5 is a partition cylinder with an inner vertical water pipe 3.
and the outer vertical water pipe 4, and a part of the peripheral wall is cut out to form a combustion gas passage port 7.
is formed. The numbers indicating other members of the vertical water tube boiler are the same as those in FIGS. 1 and 2 above. The mode shown in this embodiment is the simplest mode in which the partition cylinder 5 is rotatably provided, and the fourth mode is
As shown in the figure, it is placed on the upper surface of the lower header 2 without any gaps. In a cold state, the height of the partition cylinder 5 is slightly shorter than the inner and outer vertical water pipes 3 and 4, and there is a slight gap t between its upper edge and the lower surface of the upper header 1 (for example, 2
mm), and during operation of the boiler, the temperature is higher than that of the inner and outer vertical water pipes 3, 4, and it is desirable that the gap t becomes substantially zero due to thermal expansion. It is determined appropriately based on the thermal expansion coefficient and boiler operating conditions. Also, the combustion gas passage port 7 is shaped like a partition cylinder 5 in Fig. 4.
Although the notch is continuously cut out from the upper edge to the lower edge of the hole, it is also possible to cut out a large hole in the peripheral wall as shown in FIG. In addition, the inner vertical water pipes 3 and the outer vertical water pipes 4 do not need to be arranged on the circumference of a perfect circle as shown in the figure, but may be arranged on a substantially circular circumference, and each arrangement is not necessarily arranged on the circumference of a perfect circle as shown in the figure. They do not need to be arranged in a single row on the same circumference, for example, they may be arranged in a staggered pattern or in multiple rows. In addition, the inner vertical water pipe 3 and the outer vertical water pipe 4 do not need to be arranged in a precise concentric circle, and the interval between the inner vertical water pipe 3 and the outer vertical water pipe 4 is the combustion gas passage port 7.
that is, the combustion gas passage 9
Vertical water pipes 3 and 4 near the combustion gas passage port 7 of
It is preferable that the vertical water pipes 3 and 4 are arranged eccentrically so that the distance between them is wide and the distance between the vertical water pipes 3 and 4 is narrow in the portion near the flue 13 because the flow velocity of the combustion gas can be kept almost constant throughout. Further, in the present invention, the arrangement of the inner vertical water pipes 3 and the structure of the combustion gas passage 9 can be arranged as shown in FIG. That is, the number of inner vertical water pipes 3 is reduced. For example, the number of inner vertical water pipes in a standard vertical water tube boiler is usually:
20~ for a vertical water tube boiler with a scale of 600000Kcal/hour
Instead of 30 items, it should be 20-40% of that. Regarding the structure of the combustion gas passage 9, the shrouding plate 8 is eliminated, heat transfer fins 8' are provided between each of the outer vertical water pipes 4 to narrow the combustion gas passage 9, and the outside thereof is covered with a heat insulating material 10. With such a configuration, even if the fuel has low calorific value and high water content, such as sawdust after being used for enoki mushroom cultivation, the combustion temperature is low and the combustibility is poor. Since there are fewer of them, the total low-temperature surface area in the upper combustion chamber 6 can be reduced and the atmospheric temperature in the upper combustion chamber 6 can be raised to improve the combustion state. Furthermore, when the structure of the combustion gas passage 9 is adopted as described above, the flow velocity in the combustion gas passage 9 can be increased and the heat transfer efficiency to the outer vertical water pipe 4 can be increased.

The operation of such a vertical water tube boiler during operation is almost the same as that of the conventional vertical water tube boiler described above.
That is, starting with the partition cylinder 5 positioned so that the combustion gas passage port 7 is farthest from the flue 13 and the chimney 14 as shown in FIG. Combustion chamber 1
1, heating the heat transfer surface of the inner vertical water tube 3 while rising and completing combustion in the upper combustion chamber 6;
As it passes through the combustion gas passage port 7 and flows through the combustion gas passage 9, which is divided into left and right sides, it heats the heat transfer surface of the outer vertical water pipe 4, and the combustion gas that has finished its heating action passes through the flue 13 and reaches the chimney 14. The steam or hot water generated is taken out from the take-out pipe 15 and used for a predetermined purpose.

To clean the vertical water tube boiler according to the present invention having the above-mentioned configuration, first remove the upper cleaning port cover 17 and clean the heat transfer surface of the inner vertical water tube 3 facing into the upper combustion chamber 6 with a cleaning tool. The fact that it can be easily cleaned is the same as before. The heat transfer surface of the outer vertical water pipe 4 is prepared as follows. That is, since the operation of the boiler has already been stopped and the temperature has decreased, and a gap t has been created between the upper edge of the partition cylinder 5 and the lower surface of the upper header, the partition cylinder 5 should be operated with an appropriate input or lever. By applying rotational force by means,
The position of the combustion gas passage port 7 can be changed by easily rotating the partition cylinder 5, which is merely placed on the upper surface of the lower header 2. Thus, as shown in FIG. 5, a cleaning nozzle 22 to which a hose 21 for pumping a pressure fluid such as water or air is attached is inserted into the combustion gas passage 9 through the combustion gas passage port 7, and the pressure is released from its tip. The fluid can be jetted to thoroughly clean all the heat transfer surfaces of the nearby outer vertical water pipes 4, and the fluid can be moved sequentially to clean all the outer vertical water pipes 4. Moreover, since the structure is simple, manufacturing costs can be reduced, and vertical water tube boilers can be supplied at low cost. Furthermore, by reducing the number of inner vertical water pipes 3 arranged, fuel with a small calorific value can also be used effectively.

In the vertical water tube boiler according to the present invention, a partition cylinder 5 between an inner vertical water tube 3 and an outer vertical water tube 4 has a combustion gas passage port 7 which can also be used to insert cleaning tools, and is rotatably provided. As a result, cleaning of the outer vertical water pipe 4 is extremely easy, and it can be supplied at low cost, and valuable fuel can be used effectively, which is valuable in terms of saving energy resources.

[Brief explanation of the drawing]

Figure 1 is a horizontal sectional view (line B-B in Figure 2) passing through the center of the cleaning lid of a conventional vertical water tube boiler;
The figure is a sectional view taken along the line A-A in FIG. 1, and FIG. 3 is a horizontal cross-section (taken along the line D-D in FIG. 4) passing through the center of the vertical water tube group of an embodiment of the vertical water tube boiler according to the present invention. 4 is a sectional view taken along the line C-C in FIG. 3, FIG. 5 is an explanatory diagram showing the cleaning state, FIG. 6 is a horizontal sectional view corresponding to FIG. 3 of another embodiment, and FIG. FIG. 2 is a perspective view of a partition cylinder showing another embodiment in which only combustion gas passage ports are provided. 1... Upper header, 2... Lower header, 3...
Inner vertical water pipe, 4... Outer vertical water pipe, 5... Partition cylinder, 5'... Heat transfer fin, 6... Upper combustion chamber, 7
...Combustion gas passage port, 7'...Combustion gas passage port,
8... Shrouding plate, 8'... Heat transfer fin, 9... Combustion gas passage, 10... Heat insulation material, 11... Lower combustion chamber,
12... Combustion machine, 13... Flue, 14... Chimney,
15... Takeout pipe, 16... Upper cleaning port, 17...
Upper cleaning port, 18...Insulating material, 19...Lower cleaning port, 20...Lower cleaning port, 21...Hose,
22...Cleaning nozzle.

Claims (1)

[Claims] 1. A large number of inner vertical water pipes and a large number of outer vertical water pipes are arranged in an annular manner between the upper header and the lower header, and the combustion gas first heats the inner vertical water pipes and then burns them. In a vertical water tube boiler having a passage for combustion gas passing through a gas passage port to heat an outer vertical water pipe and then being discharged, a partition cylinder having the combustion gas passage port is provided between the inner vertical water pipe and the outer vertical water pipe. A vertical water tube boiler characterized by being rotatably installed. 2. The vertical water tube boiler according to claim 1, wherein the partition cylinder is rotatably placed on the upper surface of the lower header. 3. According to claim 1 or 2, the inner vertical water pipe and the outer vertical water pipe are eccentrically arranged in an annular shape so that the interval between the inner vertical water pipe and the outer vertical water pipe widens at the combustion gas passage port. Vertical water tube boiler as described. 4. The vertical water tube boiler according to any one of claims 1 to 3, wherein the inner vertical water pipes are arranged in one row.