JP3971865B2 - Hot gas supply device - Google Patents

Description

[0001]
[Technical field to which the invention belongs]
The present invention relates to an apparatus for supplying hot gas to a heat transfer surface tube in a waste heat boiler, and is connected to the inner wall of the boiler, particularly to the bottom, and has a thick outer jacket at its lower end, and supply of hot gas. Connected to the outer jacket above the circular inversion region forming the air opening and surrounded by the outer jacket with a space between the air supply pipe with the inflow portion narrowing in a conical shape, and the heat transfer surface pipe A connected outflow portion and a coolant derivative disposed between the outer jacket and the air supply pipe and extending near the inversion cap.
[0002]
[Prior art]
According to the applicant's brochure “Structure of the handling equipment and instrument set and pitch travel” (Verfahrenstechnik Anlagen- und Apparatebau Komponenten und Teilkreislaeufe) (1986), page 19, the device according to the above technique is known, but in that case external The thickness is surely small at the lower end of the jacket. In a waste heat boiler to which hot gas is sent, when the hot gas is supplied to the heat transfer surface tube, the critical region is reached. When hot gas having a temperature of about 1500 ° C. is fed into the air supply device, for example, the catalytic splitting of hydrocarbons does not occur under a high pressure, so that the air supply device bears a considerably high load due to heat. Furthermore, due to the tube's geometric factors and the high internal pressure of the water-filled boiler, a large load is created, so a large thermal expansion must be taken into account. In particular, in order to increase the wall thickness by increasing the wall thickness in the outer jacket and the inversion region, the load of the waste heat boiler as a gas flow rate is limited.
[0003]
In another embodiment of the known device according to the pamphlet, an outer jacket is formed with its lower end thick so as to ensure sufficient internal pressure.
[0004]
[Problems to be solved by the invention]
An object of the conventional invention is to improve cooling of a thick inversion region in a hot gas supply device.
[0005]
[Means for Solving the Problems]
This problem is solved by providing at least the outer jacket in the circumferential direction with grooves that are essentially evenly divided and essentially axially extending in the thick area inside.
[0006]
[Embodiments of the Invention]
Claims 2 to 4 relate to different embodiments in which grooves can be formed.
[0007]
In addition, the depth of the groove is reduced in the direction of the inversion region, that is, the direction in which the coolant flows.
[0008]
Eventually, the groove is connected to the inside in the circular inversion region, and the groove bottom is essentially curved in the inversion region, and the depth of the groove is continuously reduced in the direction of the supply pipe. In such a way, the inversion region is cooled particularly effectively.
[0009]
【Example】
The present invention will be described in more detail with reference to the accompanying drawings.
[0010]
FIG. 1 is a longitudinal sectional view of an embodiment of the device according to the invention, which can be compared with the drawing in “Cooled conical air supply region in a heat transfer face tube” on page 19 of the pamphlet cited above.
FIG. 2 is a cross-sectional view taken along line II-II in FIG.
FIG. 3 is a longitudinal sectional view taken along line III-III in FIG.
[0011]
In the drawings described above in the pamphlet, only a part of the wall W of the container is shown, and the apparatus 1 for supplying hot gas in the heat transfer pipe of the waste heat boiler (not shown) Joined by S1. An outer jacket 2 joined to each other on the round inversion region 4 and an air supply pipe 3 surrounded by the outer jacket 2 form part of the apparatus. In the embodiment shown in FIG. 1, the outer jacket 2 and the inversion region 4 are partly formed as a change-over cap 6 that is connected to the supply pipe 3 on the welded part S2. The direction changing cap 6 defines a gas inlet 6 a of the supply pipe 3. Although not shown, the air supply pipe 3 includes a portion 5 that narrows in a conical shape so that an outflow portion connected to the heat transfer surface tube has a right cylindrical shape.
[0012]
The outer jacket comprises a first part 7 connected to the container wall, a deformed part 8 and a thick part 9.
[0013]
The inner wall 9a of the part 9 and the inner wall 4a of the inversion region 4 are provided with grooves 10 that are essentially radially outward and arranged at equal intervals. The groove 10 is provided in the portion 9 of the outer jacket, and is constituted by a groove portion 10a that continuously increases in the direction of the depth thereof, and a groove portion 10b that has a curved bottom connected to the groove portion 10a. The depth is reduced in the direction of the tube portion 5. Also, the grooves can be divided and arranged in different ways so that the desired cooling effect can be achieved.
[0014]
A coolant derivative 11 is arranged between the outer jacket 2 and the supply pipe 3, and its free end terminates near the inversion region 4, ie above the groove. A web 12 is disposed between the grooves 10.
[0015]
The coolant K flowing between the wall of the hole B and the outer surface of the coolant derivative 11 becomes a partial flow K1, and flows into the groove 10 along the direction of the coolant K, that is, along the axial direction of the apparatus. And further flows as a partial flow K2 in the space between the upper side of the web 12 and the coolant derivative 11. These partial flows merge and flow upward in the space between the coolant derivative 11 and the inflow portion 5. Due to the partial flow entering the groove 10, the lower part 9 of the outer jacket 2 and the inversion region 4 are cooled particularly well from the inside. Thereby, the outer surface temperature of the reversing cap 4 is lowered. The web 12 arranged on the inner side has a large heat exchange surface, and the water temperature is further set to 250 ° C to 350 ° C. Thereby, the stiffness parameter in the short time range is determined by design and its value can be essentially higher than the value in the creep region (deformation region). On the other hand, the flange has a structural mechanical effect called support or reinforcement.
[0016]
In the apparatus according to the present invention, the wall thickness of the inversion region, which was conventionally 15 to 20 mm, can be reduced by about 5 mm, thereby reducing the surface temperature on the gas side by about 100K.
[0017]
Lowering the gas side surface temperature is particularly important when the hot gas entering the apparatus contains hydrogen. This is because the high surface temperature associated with the hydrogen component contained in the gas causes hydrogen embrittlement corresponding to the Nelson figure (NELSON-Diagramm).
[0018]
Thus, in the device according to the invention, a decrease in the surface temperature occurs especially in the reversal cap region of the device, i.e. in the joining tube into which the gas flows.
[Brief description of the drawings]
1 is a longitudinal sectional view of an embodiment of an apparatus according to the invention.
2 is a cross-sectional view taken along the line II-II in FIG.
3 is a longitudinal sectional view taken along line III-III in FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Apparatus 2 External jacket 3 Supply pipe 4 Inversion area 5 Pipe part 6 Inversion cap 6a Gas inlet 7 First part 8 Deformation part 9 Part 9a Inner wall 10 Groove 10a Groove part 10b Groove part 11 Coolant derivative 12 Web B Hole K Coolant K1 Partial flow K2 Partial flow S1 Welded part W Wall

Claims (6)

An outer jacket (2) connected to the inner wall of the boiler, in particular the bottom, and thick at the lower end;
An inflow portion that is connected to the outer jacket above the circular inversion region (4) in which the hot gas supply opening (6a) is formed, is surrounded by the outer jacket at an interval, and narrows in a conical shape. An air supply pipe (3);
A hot gas is supplied to the heat transfer surface tube of the waste heat boiler including the outflow portion connected to the heat transfer surface tube and the coolant derivative (11) disposed between the outer jacket and the air supply tube and extending near the reversing cap. In a device for supplying air,
At least the outer jacket (2) is provided with a groove (10) in the circumferential direction which is essentially equally divided and essentially axially elongated in the thickened region (9) on its inner side (9a). A featured hot gas supply device. The hot gas supply device according to claim 1, wherein the groove is provided in an inner wall of the outer jacket. 2. A hot gas supply device according to claim 1, characterized in that the groove is formed by a web, in particular welded to the inner wall of the outer jacket. The hot gas supply device according to claim 1, wherein the groove is formed as a uniform casting. The hot gas supply device according to any one of claims 1 to 4, wherein the depth of the groove continuously decreases in the direction in which the coolant flows, that is, in the direction of the inversion region. The groove (10a) is connected to the inside (10b) of the round inversion region, the bottom of the essentially curved groove is connected to the inversion region, and the depth of the groove is continuously reduced in the direction of the supply pipe. The hot gas supply device according to any one of claims 1 to 5.

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