JP4590741B2 - Rotary kiln - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an indirect heating type rotary kiln in which waste such as municipal waste is pyrolyzed and gasified.
[0002]
[Prior art]
In recent years, as a next-generation waste treatment system, waste is heated and pyrolyzed in a low-oxygen atmosphere, and the generated pyrolysis gas and pyrolysis residue are burned at a high temperature in a melting furnace to produce ash in the waste. A gasification / melting system has been developed in which slag is extracted as molten slag, and some demonstration operations have been carried out. In such a system, a rotary kiln is employed in order to thermally decompose and gasify the waste, and the waste is indirectly heated and dried with heat from the outside to be thermally decomposed and gasified.
[0003]
An indirect heating type rotary kiln used for pyrolyzing waste gas is an example of an outer cylinder 2 in which a refractory material 1 as a heat insulating material is lined and is horizontally long, as schematically shown in FIG. The ends in the longitudinal direction (arrow X direction), which is the longitudinal direction, are connected to the inlet tube 3 and the outlet tube 4 fixedly arranged via the rotary joint 5, and the outer tube 2 is connected to the inlet tube 3 side than the side of the inlet tube 3. The outlet cylinder 4 is arranged so as to be inclined and the inner cylinder 7 is concentrically accommodated in the outer cylinder 2, and the heating channel 6 is provided between the inner cylinder 7 and the outer cylinder 2. The kiln main body I having a double cylinder structure is configured by integrally supporting the inner cylinder 7 on the outer cylinder 2 by the support device 8, and the front and rear direction ends of the inner cylinder 7 are further formed. The supply pipe 9 and the discharge pipe 10 having a diameter smaller than that of the inner cylinder 7 communicate with each other via ring-shaped end plates 11 and 12. Continue to the supply pipe 9 to the inlet tube 3, also Aru the discharge pipe 10 so as to be respectively positioned in the outlet tube 4.
[0004]
Further, a ring gear 13 is provided on the outer peripheral portion of the outer cylinder 2 of the kiln main body I, and a drive pinion 15 attached to the shaft of the motor 14 is engaged with the ring gear 13 so that the kiln main body I can be rotated by driving the motor 14. Thus, in a state where the kiln body I is rotated at a low speed, the waste 17 thrown into the charging hopper 16 is gradually supplied into the inner cylinder 7 through the supply pipe 9 of the inlet cylinder 3 by the dust feeder 18. Meanwhile, by circulating hot air (heating gas) 19 from the outlet cylinder 4 side to the inlet cylinder 3 side in the heating flow path 6 formed between the outer cylinders 7 and 2 in the kiln body I, The waste 17 in the inner cylinder 7 is heated, dried and thermally decomposed, and the generated pyrolysis gas 17a is transferred to the outlet hopper 20 through the discharge pipe 10 of the outlet cylinder 4 and then taken out from the upper part. Thermal decomposition residue 17 containing metals After transfer to an outlet hopper 20 through the discharge pipe 10, it is so removed from the bottom.
[0005]
In the rotary kiln, when the hot air 19 is passed through the heating flow path 6 between the inner cylinder 7 and the outer cylinder 2 and the waste 17 is thermally decomposed, the outer cylinder 2 hardly expands due to the inner heat retention. 7 is thermally expanded because it is not kept warm. Therefore, the support device 8 for supporting the inner cylinder 7 on the outer cylinder 2 needs to have a function of absorbing the difference in thermal expansion amount. For this reason, the support device 8 is mounted at a position (for example, a position at an interval of 60 degrees) that is spaced apart in the circumferential direction at positions such as both ends of the inner cylinder 7 and the outer cylinder 2 in the front-rear direction. As shown in an enlarged example, a cylindrical casing 22 having an inner end opened and an outer end closed by a closing plate 21 is installed in the outer wall portion of the outer cylinder 2 so as to penetrate in the radial direction. Further, a pin 24 having an outer diameter slightly smaller than the inner diameter of the cylindrical casing 22 and having a hollow portion 23 formed in the axial direction inside the outer end portion is slidably accommodated, and penetrates the closing plate 21. The tip of the bolt 26 screwed and positioned by the nut 25 is inserted into the cavity 23 movably from the outside, and the pressure receiving plate disposed in the cavity 23 at the tip of the bolt 26. 27 is fixed to the pressure receiving plate 27 in the cavity 23. The inserted compression spring 28 is brought into pressure contact so that the tip end portion which is the inner end portion of the pin 24 is always urged radially inward by the compression reaction force of the spring 28. The distal end portion is configured to be fitted in a concave pin receiver 29 assembled outwardly on the peripheral surface portion of the inner cylinder 7 so as to have a gap S, and the radial heat between the inner and outer cylinders 7 and 2 The expansion difference is absorbed by the radial sliding of the pin 24, and the longitudinal thermal expansion difference between the inner and outer cylinders 7, 2 is absorbed by the gap S between the tip end portion of the pin 24 and the pin receiver 29. I am trying to make it.
[0006]
[Problems to be solved by the invention]
However, in the case of the support device 8, since the spring 28, the pressure receiving plate 27, and the like must be incorporated in the pin 24, not only the structure is complicated, but also from the viewpoint of manufacturing and mounting accuracy of the inner cylinder 7 and the outer cylinder 2. Assembling of the pin 24 itself has difficulty, and furthermore, in order to absorb thermal expansion, the structure has a large backlash and the impact due to the backlash acts on the pin 24, so the pin strength must be increased. There are problems such as.
[0007]
Therefore, the present invention is intended to simplify the structure of the support device.
[0008]
[Means for Solving the Problems]
In order to solve the above-mentioned problem, the present invention is configured to rotate the outer cylinder arranged sideways and the inner cylinder accommodated concentrically in the outer cylinder, while rotating the waste supplied into the inner cylinder. In the rotary kiln designed to be pyrolyzed and gasified by hot air flowing through the heating flow path formed between the inner cylinder and the outer cylinder, the required circumferential distance between the longitudinal end faces of the inner cylinder is the longitudinal direction. A bracket attached at a position, a bracket arranged to overlap the bracket in the front-rear direction and attached to the inner peripheral surface of the outer cylinder, and a support pin that penetrates both brackets from the front-rear direction and connects the brackets It is set as the structure which made the said outer cylinder support the outer cylinder with the support apparatus which consists of this.
[0009]
Since a support device having a simple structure using a bracket and a support pin is employed, it can be easily assembled between the inner and outer cylinders.
[0012]
Further, the outer cylinder as an outer thermal insulation structure by thermal expansion of the inner cylinder and the outer cylinder is configured such that in such a manner that the same, only the shear forces due to the weight of primarily the inner cylinder to the support pin of the support device acting This eliminates the need for a large estimate of pin strength.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0014]
FIGS. 1A and 1B show an embodiment of the present invention. In the same configuration as the rotary kiln shown in FIG. 5, instead of providing the refractory material 1 on the inner surface of the outer cylinder 2, The refractory material 1 is provided outside the cylinder 2 and the heating flow path 6 serving as a gap between the inner cylinder 7 and the outer cylinder 2 is set as narrow as possible so that the thermal expansion amount between the inner cylinder 7 and the outer cylinder 2 is set. The inner cylinder 7 and the outer cylinder 2 are supported by the supporting device 8 having a pin having a spring structure shown in FIG. The both ends of the cylinder 7 on the supply side and the discharge side are performed by the support device 30 having a simple pin connection structure.
[0015]
The above support device 30 will be described in detail. FIGS. 1A and 1B show the case where the inner cylinder 7 is supported on the outer cylinder 2 at the end of the inner cylinder 7 on the discharge pipe 10 side for convenience of explanation. Thus, two support plates 31 are provided so as to project rearward at the circumferentially required positions on the outer peripheral portion of the outer side surface (rear side surface) of the end face plate 12 and have pin holes 32a on the support plate 31. The brackets 32 are arranged in parallel in the longitudinal direction of the inner cylinder 7 in the front-rear direction (arrow X direction) at a required interval and parallel to the end face plate 12, and the bracket 33 has a pin hole 33 a between the two brackets 32. Are inserted and arranged so that a minute gap ΔS ₁ in the front-rear direction is formed between both brackets 32, and the bracket 33 is placed on the outer cylinder 2 so that the position of the pin hole 33 a coincides with the pin hole 32 a. Attach to the inner surface and A support pin 34 with a flange 34a having a diameter slightly smaller than that of the pin holes 32a, 33a is inserted into the pin holes 32a, 33a of the flanges 32, 33 in the front-rear direction, and the flange 34a is inserted into the bracket 32 with bolts 35. The brackets 32 and 33 are fixedly connected to each other, and a minute gap ΔS ₂ is set between the inner diameters of the pin holes 32 a and 33 a of the brackets 32 and 33 and the outer diameter of the support pin 34. The end of the inner cylinder 7 on the supply pipe side has the same configuration.
[0016]
In the above configuration, the support device 30 has a simple structure composed of the support plate 31, the brackets 32 and 33, and the support pins 34, and therefore can be easily assembled to the portion between the inner and outer cylinders 7 and 2. When such a support device 30 is used, when the outer cylinder 2 is rotated by driving the motor 14 in the same manner as shown in FIG. 5 , the rotational force is generated by the bracket 33, the support pin 34, the bracket 32, and the support plate 31. Therefore, the inner cylinder 7 and the outer cylinder 2 can be rotated together.
[0017]
When the operation is performed, since the hot air 19 flows through the narrow heating flow path 6 between the inner cylinder 7 and the outer cylinder 2 that is kept outside, both the inner cylinder 7 and the outer cylinder 2 are directly heated. 7 and the outer cylinder 2 can have substantially the same amount of thermal expansion. Therefore, there is no need for a large gap around the support pin 34 connecting the brackets 32 and 33 to absorb the difference in thermal expansion in the radial direction, and it is sufficient that there is a minute gap ΔS ₂ . For this reason, the support pin 34 is not subjected to an impact due to a large ratchet, and only a shearing force due to the weight of the inner cylinder 7 is mainly applied, so that it is not necessary to estimate the pin strength greatly. The whole can be made compact. In addition, due to the above, there is almost no difference in the thermal expansion between the inner cylinder 7 and the outer cylinder 2 in the front-rear direction, but a minute gap ΔS ₁ is set between the brackets 32, 33. Even if a slight difference in thermal expansion occurs in the direction, the difference in thermal expansion in the front-rear direction can be absorbed by the minute gap ΔS ₁ .
[0018]
Next, FIG. 2 shows another form of the support device . In the same configuration as the rotary kiln shown in FIGS. 1 (a) and 1 (b), brackets 32 and 33 attached to the inner cylinder 7 and the outer cylinder 2, respectively. Instead of the support device 30 including the support pins 34, the support device 37 is configured so that the inner cylinder 7 is supported by the support pins 36 radially disposed on the outer cylinder 2.
[0019]
That is, the rear end of the inner cylinder 7 in the front-rear direction as shown in FIG. 2 showing the case where the inner cylinder 7 is supported by the outer cylinder 2 at the end of the inner cylinder 7 on the discharge pipe 10 side as in FIG. Is extended to the rear by a required amount, and a pin hole 39 is formed at a required circumferential position of the extended end portion 7a, while the pin hole 39 is formed at a position corresponding to the pin hole 39 of the outer cylinder 2. Pin holes 40 are formed in accordance with the pitch of the holes 39, and support pins 36 with collar portions 36 a are inserted from the outside into the respective pin holes 40 of the outer cylinder 2, and are radially inserted into the pin holes 39 of the inner cylinder 7. And a seal member 38 is interposed in the seal portion between the collar portion 36a of the support pin 36 and the outer cylinder 2, and the collar portion 36a is detachably attached to the outer cylinder 2 with bolts 41 and fixed. You can make it, the small gap [Delta] S ₃ between the outer diameter of the inner diameter and the support pins 36 of the pin hole 39 is formed So as to.
[0020]
In the case of the support device 37 shown in FIG. 2, there is no welded portion of the support plate 31 and the brackets 32 and 33 as in the support device 30 shown in FIGS. In this case, the support pin 36 is mounted from the outside of the outer cylinder 2, and the pin hole 40 of the outer cylinder 2 is more required than the support pin 36. Since the amount is increased, the support pin 36 can be easily mounted. Further, when a radial thermal expansion difference occurs between the inner cylinder 7 and the outer cylinder 2, it can be absorbed by a radial relative displacement between the pin hole 39 of the inner cylinder 7 and the support pin 36. When a difference in thermal expansion in the front-rear direction occurs between the inner cylinder 7 and the outer cylinder 2, it can be absorbed by the minute gap ΔS ₃ between the pin hole 39 of the inner cylinder 7 and the support pin 36. .
[0021]
Then, Figure 3 shows still another embodiment of the supporting device, the bosses 42 on the position of the same configuration as the supporting device 37 shown in FIG. 2, the pin hole provided in the extended end portion 7a of the inner cylinder 7 The support device 37A is configured such that the support pin 36 is inserted with the inner diameter portion of the boss 42 as a pin hole 39.
[0022]
As shown in FIG. 3, when the boss 42 is assembled to the extended end 7 a of the inner cylinder 7 so that the pin hole 39 is formed by the boss 42, the pin hole 39 can be reinforced, and the outer cylinder 2 Since the support strength of the inner cylinder 7 can be stabilized and structurally advantageous, the number of support devices provided in the circumferential direction can be reduced.
[0023]
Further, FIG. 4 shows a further embodiment of the support device, in a similar configuration as the supporting device 37 shown in FIG. 2, the inner periphery of the pin hole 39 provided in the extended end portion 7a of the inner cylinder 7 The support device 37B is formed by attaching a reinforcing ring 43 made of a steel material such as an angle material by welding or bolts.
[0024]
As shown in FIG. 4, when the pin hole 39 part is reinforced with a reinforcing ring 43 made of steel mold material, the weight can be reduced as compared with the case where the thick boss 42 as shown in FIG. 3 is used.
[0025]
In the embodiment shown in FIGS. 1A and 1B, the case where two brackets 32 are attached to the inner cylinder 7 side and one bracket 33 is attached to the outer cylinder 2 side is shown. The pin hole 39 of the extended end portion 7a of the inner cylinder 7 in the embodiment shown in FIGS. 2, 3, and 4 is slightly larger than the outer diameter of the support pin 36. However, it is of course possible to provide a long hole that is slightly longer in the front-rear direction, and various changes can be made without departing from the scope of the present invention.
[0026]
【The invention's effect】
As described above, according to the rotary kiln of the present invention, the waste supplied to the inner cylinder while integrally rotating the outer cylinder arranged sideways and the inner cylinder stored concentrically in the outer cylinder. In a rotary kiln that is pyrolyzed and gasified by hot air flowing through a heating flow path formed between the inner cylinder and the outer cylinder, and required in the circumferential direction of both front and rear direction end faces that are the longitudinal direction of the inner cylinder A bracket that is attached to the space, a bracket that is placed so as to overlap the bracket in the front-rear direction, and that is attached to the inner peripheral surface of the outer cylinder. by comprising a pin support device, since a structure in which so as to support the inner cylinder into the outer cylinder, it is possible to support the inner cylinder to the outer cylinder by the support device of simple structure, also, the outer cylinder As an outer thermal insulation structure by thermal expansion of the inner cylinder and the outer cylinder is configured such that in such a manner that the same, so that the support pins are used to support device acts only shear forces due to the weight of the inner cylinder mainly As a result, the pin strength does not need to be greatly estimated, and the support device can be downsized.
[Brief description of the drawings]
FIG. 1 shows an embodiment of a rotary kiln of the present invention, in which (a) is a cut side view of a support device assembled between a discharge pipe side end of an inner cylinder and an outer cylinder, and (b) is It is an AA direction arrow directional view of (i).
Is another shown to disconnect side view the form of a supporting device for supporting the FIG. 2 inner tube and the outer tube.
It is further shown to disconnect side view another embodiment of a support device for supporting the Figure 3 inner tube and the outer tube.
It is further shown to disconnect side view another embodiment of a support device for supporting the Figure 4 inner tube and the outer tube.
FIG. 5 is a schematic view showing an example of a conventional rotary kiln.
FIG. 6 is an enlarged cross-sectional view of a support device used in a conventional rotary kiln.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Refractory material 2 Outer cylinder 6 Heating flow path 7 Inner cylinder 17 Waste 19 Hot air 30 Support apparatus 32, 33 Bracket 34, 36 Support pin 37, 37A, 37B Support apparatus 39, 40 Pin hole

Claims (2)

  The waste supplied to the inner cylinder was formed between the inner cylinder and the outer cylinder while the outer cylinder arranged in the horizontal direction and the inner cylinder stored concentrically in the outer cylinder were rotated together. In a rotary kiln designed to be pyrolyzed and gasified by hot air flowing through the heating flow path, brackets attached to the circumferentially required interval positions of both end portions in the longitudinal direction that are the longitudinal direction of the inner cylinder, and the brackets and the longitudinal direction The inner cylinder is connected to the outer cylinder by a support device comprising a bracket arranged so as to overlap with each other and attached to the inner peripheral surface of the outer cylinder, and a support pin that penetrates both brackets in the front-rear direction and connects the brackets. A rotary kiln characterized by having a configuration adapted to be supported on a rotary kiln. Rotary kiln of the outer cylinder as an outer thermal insulation structure, according to claim 1, wherein the thermal expansion of the inner cylinder and the outer cylinder was set to the same.

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