Composite sealing device for positive pressure of external heating type jacket sleeve rotary pyrolyzing furnace

Abstract

The invention discloses a composite sealing device for positive pressure of an external heating type jacket sleeve rotary pyrolyzing furnace, which comprises a double multi-layer composite sealing structure, the first multi-layer composite sealing structure is arranged between a feeding / discharging furnace cover and the rotary pyrolyzing furnace, and the first multi-layer composite sealing structure comprises a heat insulation structure, a telescopic structure, a dynamic sealing structure, a high-temperature sealing filler structure and a flexible sealing structure from inside to outside; the positive pressure device is used for realizing positive pressure operation in the rotary pyrolyzing furnace; the second multi-layer composite sealing structure is arranged between the outer jacket sleeve and the rotary pyrolyzing furnace and comprises a heat insulation structure, a movable sealing structure, a high-temperature sealing filler structure, a flexible sealing structure and a telescopic layer structure from inside to outside, and zero-leakage sealing of high-temperature gas in the outer sleeve can be achieved in the heating and cooling state and the high-temperature state between the outer sleeve and the rotary pyrolyzing furnace. Through the design of the gas sealing gas, the pressure and flow of the gas sealing gas can be automatically adjusted along with the fluctuation change of the pressure in the rotary pyrolyzing furnace or the outer jacket sleeve, an environment higher than the pressure in the furnace or the outer jacket sleeve is formed, and positive pressure adjustment is achieved.

Description

Technical Field

[0001] The invention relates to the technical field of rotary kiln sealing devices, in particular to a composite sealing device for positive pressure of an externally heated jacketed rotary pyrolysis furnace. Background Art

[0002] With the development of rotary kiln technology, rotary kilns have been applied to multiple technical fields, including the resource utilization of domestic waste and waste agricultural and forestry biomass. In order to further improve the resource utilization efficiency of domestic waste and waste agricultural and forestry biomass and the thermal efficiency of the entire treatment process, external heating rotary pyrolysis furnaces are currently used to pyrolyze domestic waste and waste agricultural and forestry biomass. After part of the gas produced by pyrolysis is burned, the high-temperature flue gas is passed into the outer sleeve of the rotary pyrolysis furnace, and the material in the furnace is heated and pyrolyzed through heat transfer from the furnace body. In order to further improve the processing capacity of the rotary pyrolysis furnace and reduce the power consumption of the induced draft fan at the back end of the flue gas treatment process, the pressure inside the rotary pyrolysis furnace needs to be further increased.

[0003] At present, most rotary kilns are operated under negative pressure, and flexible rubber seals are installed at the head and tail. However, this sealing device can only solve the problem of a small amount of air leakage under negative pressure in the furnace, and cannot solve the problem of gas leakage to the outside in the furnace under positive pressure. The operating temperature of the external heating jacketed rotary pyrolysis furnace is between 400-600℃, and the operating temperature in the outer jacket is between 800-1000℃. Due to the long furnace body, the furnace body expands due to heat at high temperature, which will cause the furnace body to deform, causing the sealing surface to move toward the axial side, causing the pyrolysis gas and high-temperature flue gas in the furnace to leak. Since pyrolysis gas is a combustible gas, leakage at high temperature will cause fire or explosion risks, affecting the safe operation of the pyrolysis furnace. In addition, due to the high temperature of the furnace body, if the original flexible sealing material is used, it cannot be used at this temperature.

[0004] Purpose of the Invention In order to solve the leakage problem of pyrolysis gas of domestic garbage and waste agricultural and forestry biomass and high-temperature gas in the outer jacket sleeve when the externally heated jacketed rotary pyrolysis furnace is operating at positive pressure, the present invention provides a composite sealing device for the positive pressure of the externally heated jacketed rotary pyrolysis furnace. Through the multi-layer composite sealing structure formed respectively between the furnace cover, the outer jacket sleeve and the rotary pyrolysis furnace, the positive pressure zero leakage operation of the pyrolysis furnace or the outer jacket sleeve is achieved.

[0005] The technical solution of the present invention is as follows: A composite sealing device for positive pressure of an externally heated jacketed rotary pyrolysis furnace comprises a double multi-layer composite sealing structure arranged on the rotary pyrolysis furnace: the first multi-layer composite sealing structure is arranged between the feed / discharge furnace cover and the rotary pyrolysis furnace, and is used for realizing positive pressure operation in the rotary pyrolysis furnace; the second multi-layer composite sealing structure is arranged between the outer jacketed sleeve and the rotary pyrolysis furnace, and is used for realizing high temperature positive pressure operation of the outer jacketed sleeve.

[0006] The first-layer multi-layer composite sealing structure includes a heat insulation bin, an elastic corrugated structure, a dynamic sealing structure, a graphite filler bin, and a rubber flexible sealing structure, which are sequentially arranged along the axial direction of the rotary pyrolysis furnace.

[0007] The heat-insulating bin one is located between the inner wall of the hood head, the inner wall of the furnace cover plate and the outer wall of the rotary pyrolysis furnace body, and is an overall hollow-bin annular structure. A reserved gap one is provided between the heat-insulating bin one and the outer wall of the rotary pyrolysis furnace body.

[0008] The elastic corrugation structure 1 includes a pull rod 1 and an elastic corrugation 1. The pull rod 1 is connected between the furnace cover plate and the dynamic sealing structure 1 by bolts. The two ends of the elastic corrugation 1 are respectively welded to the furnace cover plate and the dynamic sealing structure 1. The expansion and contraction amount of the elastic corrugation 1 can be adjusted by adjusting the tightness of the nut.

[0009] The dynamic sealing structure includes a static ring seal, a dynamic ring seal, a gas seal gas inlet, and a gas seal gas outlet pressure port. The dynamic ring seal is welded and fixed to the wall of the rotary pyrolysis furnace body. The dynamic ring seal rotates along with the rotary pyrolysis furnace body. The dynamic ring seal and the static ring seal are toothed bite structures. A radial gap and an axial gap are left between the dynamic ring seal and the static ring seal. The size of the axial gap is adjusted by the expansion and contraction of the elastic corrugation. The axial gap is adjusted so that the dynamic ring seal and the static ring seal work together to achieve positive pressure and zero leakage operation in the pyrolysis furnace.

[0010] An annular empty bin structure is formed by the outer wall of the dynamic sealing structure, the upper pressure cover plate, the outer cover plate and the outer wall of the rotary pyrolysis furnace. Graphite filler is placed in the annular empty bin structure and filled to form a graphite filler bin, which is used to block the axial gap at the outermost end of the dynamic sealing structure. The outer wall of the dynamic sealing structure, the outer cover plate and the upper pressure cover plate are respectively connected by bolts. When the axial gap between the dynamic ring seal and the static ring seal is adjusted, the dynamic sealing structure drives the upper pressure cover plate and the outer cover plate to move to adjust the pressure strength of the graphite filler, thereby achieving zero leakage of the air-sealed gas in the dynamic sealing structure.

[0011] The rubber flexible sealing structure is formed by overlapping a rubber sheet connecting plate, a support plate, and a staggered rubber sheet. The rubber sheet connecting plate is fixed to the outer wall of the outer cover plate, and the support plate is welded and fixed to the furnace body of the rotary pyrolysis furnace. The two ends of the staggered rubber sheet are respectively connected to the rubber sheet connecting plate and the support plate by steel wire bundling, and a corresponding annular flexible sealing state is formed between the three components.

[0012] The further design of the first multi-layer composite sealing structure is as follows: Furthermore, the cross-section of the insulation bin 1 is rectangular, the side of the insulation bin 1 facing the inside of the rotary pyrolysis furnace is in direct contact with the high-temperature gas in the furnace, the outer annular surface and the outer side surface are respectively tightly attached to the inner wall of the hood head and the inner wall of the furnace cover plate, the inner annular surface is flush with the inner end surface of the furnace cover plate, and a reserved gap 1 is formed between the inner annular wall surface, the inner end surface of the furnace cover plate and the outer wall of the rotary pyrolysis furnace.

[0013] Furthermore, the length and width of a cross section of the heat insulation bin are respectively: L1=(φ1-Φ) / 2-C1, W1=1 / 2L1 Among them, L1 is the length of the cross section, φ1 is the inner diameter of the feed furnace cover or the inner diameter of the discharge furnace cover, Φ is the outer diameter of the rotary pyrolysis furnace, C1 is the reserved gap, and the reserved gap is 2-10mm; W1 is the width of the cross section.

[0014] Furthermore, the thickness of the wall of the heat-insulating chamber 1 is 2-20 mm, the interior of the heat-insulating chamber 1 is a vacuum environment, and the vacuum degree is 80-100 kPa. The heat-insulating chamber can effectively reduce the heat dissipation of the pyrolysis furnace to the outside.

[0015] Furthermore, in the dynamic sealing structure 1, one side of the static ring seal 1 is welded and fixed to the elastic corrugation 1, and the other side is bolted to the upper pressure cover plate.

[0016] Furthermore, the radial clearance between the dynamic ring seal 1 and the static ring seal 1 is 1-20 mm, and the axial initial installation clearance between the dynamic ring seal 1 and the static ring seal 1 is 1-40 mm.

[0017] Furthermore, the upper pressure cover plate is a concave structure, and the two raised outer walls in the concave structure are respectively connected to the dynamic ring seal and the outer cover plate bolts. The adjusting bolts drive the outer cover plate to compact the graphite filler, thereby achieving zero leakage of the air seal gas in the dynamic sealing structure.

[0018] Furthermore, the rubber sheet connecting plate is made by bending a steel ring; with the bending portion as the boundary, the outer edge of the steel ring is tightly attached to the outer wall of the outer cover plate and connected by bolts, and the angle formed by the inner edge of the steel ring and the outer cover plate is α, and α is 1-90°.

[0019] Furthermore, the staggered-layer rubber sheet 1 is composed of three layers of rubber sheets arranged in staggered layers.

[0020] For the first-layer multi-layer composite sealing structure, a gas regulating valve is set at the gas sealing gas inlet to control the gas sealing gas flow rate; a pressure transmitter is set at the gas sealing gas outlet pressure port to measure the gas sealing gas outlet pressure, and this pressure is interlocked with the pressure inside the rotary pyrolysis furnace and the gas sealing gas inlet regulating valve. In the initial state, when the pressure inside the rotary pyrolysis furnace is normal pressure, the gas sealing gas is not introduced at this time; after the dynamic sealing structure is introduced and the gas sealing gas moves and works: when the pressure inside the rotary furnace increases, the gas sealing gas pressure automatically adjusts to match the pressure inside the furnace, and is greater than or equal to the pressure inside the furnace; when the pressure inside the furnace increases, the gas sealing gas adjustment automatically increases to match the pressure inside the furnace. Specifically: when the pressure inside the rotary pyrolysis furnace is greater than the gas sealing gas outlet pressure, the gas sealing gas inlet regulating valve automatically opens the gas sealing gas flow rate of the atmospheric gas sealing inlet; when the pressure inside the rotary pyrolysis furnace is less than or equal to the gas sealing gas outlet pressure, the gas sealing gas inlet regulating valve remains unchanged. The flow rate in the gas sealing flow channel should be between 1-10m / s.

[0021] The second multi-layer composite sealing structure is provided with a second insulation chamber, a second dynamic sealing structure, a graphite packing ring, a second elastic corrugated structure, and a second rubber flexible sealing structure in sequence from the inside to the outside along the axial direction of the rotary pyrolysis furnace.

[0022] The second heat insulation bin is arranged between the furnace body of the rotary pyrolysis furnace and the outer jacket sleeve. The second heat insulation bin and the outer jacket sleeve are welded as a whole. There is a reserved gap second between the second heat insulation bin and the outer wall of the furnace body of the rotary pyrolysis furnace.

[0023] The dynamic sealing structure 2 includes a static ring seal 2, a dynamic ring seal 2, a gas seal gas inlet 2, and a gas seal gas outlet pressure port 2. The dynamic ring seal 2 is welded and fixed on the furnace body of the rotary pyrolysis furnace. The ring seal 2 rotates along with the furnace body of the rotary pyrolysis furnace. The static ring seal 2 is fixed to the outer jacket sleeve cover plate with bolts. There is a toothed bite structure between the dynamic ring seal 2 and the static ring seal 2. A radial gap and an axial gap are left between the dynamic ring seal 2 and the static ring seal 2. The axial gap is adjusted so that the dynamic ring seal 2 and the static ring seal 2 work together, and the positive pressure zero leakage operation of the outer jacket sleeve of the pyrolysis furnace is achieved through the dynamic sealing structure 2.

[0024] An inner ring and an outer ring of graphite packing rings are arranged between the outer end face of the dynamic sealing structure 2 and the pressure cover plate; the inner ring of graphite packing ring is formed by the outer end face of the dynamic sealing structure 2 and the pressure cover plate pressing the graphite packing; the outer end face of the dynamic sealing structure 2 and the surface of the pressure cover plate are respectively provided with corresponding annular grooves, and the graphite packing is filled and pressed between the two annular grooves to form an outer ring of graphite packing ring; the compaction degree of the graphite packing is adjusted by the expansion and contraction degree of the elastic corrugated structure.

[0025] The elastic corrugation structure 2 includes an elastic corrugation 2, a pull rod 2 and a fixed plate. The two ends of the elastic corrugation 2 are respectively welded to the pressure cover plate and the fixed plate. The pull rod 2 is installed between the pressure cover plate and the fixed plate by bolt connection. The expansion and contraction amount of the elastic corrugation 2 can be adjusted by adjusting the tightness of the nut of the pull rod 2.

[0026] The second rubber flexible sealing structure includes a second rubber sheet connecting plate, a second support plate, and a second staggered rubber sheet. The rubber sheet connecting plate is fixed on the pressure cover plate, and the support plate is fixedly welded to the upper surface of the static ring. The two ends of the staggered rubber sheet are respectively connected to the rubber sheet connecting plate and the support plate by steel wire bundling. The three components are overlapped to form a rubber flexible sealing effect.

[0027] The further design for the second multi-layer composite sealing structure is as follows: Furthermore, the heat-insulating chamber 2 is also an empty chamber type annular structure, and the cross section of the heat-insulating chamber 2 is a rectangle, and the length and width of the cross section are respectively: L2=(φ2-Φ) / 2-C2, W2=1 / 2L2 Among them, L2 is the length of the section, φ2 is the inner diameter of the outer jacket sleeve, Φ is the outer diameter of the rotary pyrolysis furnace, C2 is the reserved gap, and the second reserved gap is 2-10mm; W2 is the width of the section.

[0028] Furthermore, the thickness of the wall of the heat-insulating chamber 2 is 2-20 mm, the interior of the heat-insulating chamber 2 is a vacuum environment, and the vacuum degree is 80-100 kPa. The heat-insulating chamber 2 can effectively reduce the heat dissipation of the pyrolysis furnace to the outside.

[0029] Furthermore, in the dynamic sealing structure 2, the radial clearance between the dynamic ring seal 2 and the static ring seal 2 is 1-20mm, and the axial initial installation clearance between the dynamic ring seal 2 and the static ring seal 2 is 1-40mm; the axial clearance between the dynamic ring seal 2 and the static ring seal 2 is adjusted by the expansion and contraction of the elastic corrugated structure.

[0030] Furthermore, the rubber sheet connecting plate 2 is made of an L-shaped steel ring bent with two bending points as boundaries. The outer ring part of the steel ring is tightly attached to the outer wall of the pressure cover plate and connected by bolts. The middle part of the steel ring is perpendicular to the pressure cover plate, and the inner ring part of the steel ring is bent toward the rotary pyrolysis furnace. The angle between the middle part and the inner ring part of the steel ring is β, and the value of β is 91-179°.

[0031] Furthermore, the staggered-layer rubber sheet 2 is composed of three layers of rubber sheets arranged in staggered layers.

[0032] Furthermore, the sealing gases in the double-layer multi-layer composite sealing structure are air or nitrogen.

[0033] For the second-layer multi-layer composite sealing structure, gas-sealing gas is introduced, and a gas regulating valve is set at the second gas-sealing gas inlet to control the gas-sealing gas flow rate; a pressure transmitter is set at the second gas-sealing gas outlet pressure port to measure the gas-sealing gas outlet pressure, and this pressure is interlocked with the pressure inside the outer jacket sleeve of the rotary pyrolysis furnace and the gas regulating valve at the second gas-sealing gas inlet; when the pressure inside the rotary pyrolysis furnace is greater than the gas-sealing gas outlet pressure, the gas-sealing gas inlet regulating valve automatically opens the atmospheric gas-sealing gas inlet flow rate, and when the pressure inside the rotary pyrolysis furnace is less than or equal to the gas-sealing gas outlet pressure, the gas regulating valve at the second gas-sealing gas inlet remains unchanged.

[0034] The beneficial effects embodied by the present invention are specifically as follows: (1) The present invention is provided with a double multi-layer composite sealing structure, which can realize positive pressure zero leakage operation of the pyrolysis furnace and the outer jacket sleeve.

[0035] (2) The gas seal design of the dynamic seal structure in the multi-layer composite seal structure can automatically adjust the gas seal pressure and flow rate following the fluctuation of pressure inside the rotary pyrolysis furnace or the outer jacket sleeve, forming a pressure environment higher than that inside the furnace or the outer jacket sleeve, thereby realizing positive pressure regulation of the pyrolysis furnace or the outer jacket sleeve. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 It is a schematic diagram of the cross-sectional structure of the present invention.

[0037] Figure 2 for Figure 1 An enlarged structural diagram of the first-layer multi-layer composite sealing structure at A in the middle.

[0038] Figure 3 for Figure 1 An enlarged schematic diagram of the second multi-layer composite sealing structure at B in the middle.

[0039] Figure 4 It is a structural schematic diagram of the rubber flexible sealing structure 1 of the present invention.

[0040] Figure 5 It is a structural schematic diagram of the rubber flexible sealing structure 2 of the present invention.

[0041] The markings in the figure are: 1 hood head, 101 furnace cover plate, 102 heat insulation bin one, 103 tie rod one, 104 elastic corrugation one, 105 static ring seal one, 106 dynamic ring seal one, 107 gas seal gas inlet one, 108 gas seal gas outlet pressure tap one, 109 upper pressure cover plate, 110 outer cover plate, 111 graphite packing bin, 112 rubber sheet connecting plate one, 113 support plate one, 114 staggered rubber sheet one; 2 external sleeve, 201 external sleeve cover plate, 202 heat insulation chamber 2, 203 pull rod 2, 204 elastic corrugation 2, 205 static ring seal 2, 206 dynamic ring seal 2, 207 gas seal gas inlet 2, 208 gas seal gas outlet pressure tap 2, 209 pressure cover plate, 210 fixed plate, 211 inner circle graphite packing ring, 212 outer circle graphite packing ring, 213 rubber sheet connecting plate 2, 214 support plate 2, 215 staggered rubber sheet 2; 3 Rotary pyrolysis furnace body. DETAILED DESCRIPTION

[0042] like Figure 1 As shown, the rotary pyrolysis furnace is arranged horizontally, the external heating jacket sleeve is sleeved on the rotary pyrolysis furnace, and the rotary pyrolysis furnace is provided with the double multi-layer composite sealing structure of the present invention.

[0043] The second multi-layer composite sealing structure is arranged between the outer jacket sleeve and the rotary pyrolysis furnace to realize high temperature positive pressure operation of the outer jacket sleeve 2.

[0044] The first multi-layer composite sealing structure is arranged between the feeding / discharging furnace cover and the rotary pyrolysis furnace, and includes a heat insulation chamber 102, an elastic corrugated structure 1, a dynamic sealing structure 1, a graphite filling chamber 111, and a rubber flexible sealing structure 1 which are arranged in sequence along the axial direction of the rotary pyrolysis furnace. When the rotary pyrolysis furnace is operated under positive pressure, the high-temperature gas in the furnace first passes through the heat insulation chamber, which can effectively reduce the heat dissipation of the high-temperature gas in the furnace to the outside, and then the positive pressure operation of the rotary pyrolysis furnace is realized through the elastic corrugated structure 1, the dynamic sealing structure 1, the graphite filling chamber 111, and the rubber flexible sealing structure 1.

[0045] The heat-insulating chamber 102 is located between the inner wall of the hood head 1, the inner wall of the furnace cover plate 101 and the outer wall of the rotary pyrolysis furnace. The overall structure is an empty chamber type annular structure with a rectangular cross section, including an outer ring surface, an inner ring surface, an inner side surface and an outer side surface. The inner side surface is in direct contact with the gas in the rotary pyrolysis furnace. The outer ring surface and the outer side surface are respectively close to the inner wall of the hood head 1 and the inner wall of the furnace cover plate 101. The inner ring surface is flush with the inner end surface of the furnace cover plate 101. A reserved gap 1 is formed between the inner ring wall surface, the inner end surface of the furnace cover plate 101 and the outer wall of the rotary pyrolysis furnace. The chamber wall thickness of the heat-insulating chamber 102 is 2-20mm. The interior of the heat-insulating chamber 102 is a vacuum environment with a vacuum degree of 80-100kpa. The heat-insulating chamber can effectively reduce the heat dissipation of the pyrolysis furnace outward.

[0046] The length and width of the cross section of the heat insulation chamber 102 are respectively: L1=(φ1-Φ) / 2-C1, W1=1 / 2L1 Among them, L1 is the length of the cross section, φ1 is the inner diameter of the feed furnace cover or the inner diameter of the discharge furnace cover, Φ is the outer diameter of the rotary pyrolysis furnace, C1 is the reserved gap, and the reserved gap is 2-10mm; W1 is the width of the cross section.

[0047] The elastic corrugation structure 1 includes a pull rod 103 and an elastic corrugation 104. The pull rod 103 is connected between the furnace cover plate 101 and the dynamic sealing structure 1 by bolts. The two ends of the elastic corrugation 104 are respectively welded to the furnace cover plate 101 and the dynamic sealing structure 1. The width of the pull rod 103 between the furnace cover plate 101 and the dynamic sealing structure 1 is adjusted by adjusting the tightness of the nut to adjust the expansion and contraction of the elastic corrugation 104, thereby adjusting the axial gap between the dynamic and static ring seals 105 in the dynamic sealing structure 1 caused by the thermal expansion of the furnace body to become smaller, thereby ensuring that the axial gap between the dynamic and static ring seals 105 is within a reasonable range.

[0048] The dynamic seal structure 1 includes a static ring seal 105, a dynamic ring seal 106, a gas seal gas inlet 107, and a gas seal gas outlet pressure port 108. The dynamic ring seal 106 is welded and fixed on the outer wall of the rotary pyrolysis furnace body 3. There is a tooth-shaped bite structure between the dynamic ring seal 106 and the static ring seal 105. There is a radial gap and an axial gap between the dynamic ring seal 106 and the static ring seal 105. The radial gap is 1-20mm, and the axial initial installation gap between the dynamic ring seal 106 and the static ring seal 105 is 1-40mm. Among them, the size of the axial gap is adjusted by the expansion and contraction of the elastic corrugation 104, and the axial gap is adjusted so that the dynamic ring seal 106 and the static ring seal 105 work in coordination. The dynamic sealing structure can increase the flow resistance of the high-temperature gas in the furnace to the outside of the furnace. Through the automatic adjustment of the dynamic sealing gas pressure and flow, a small amount of cold air is introduced into the furnace, which effectively isolates the high-temperature gas from flowing outward, thereby realizing positive pressure and zero leakage operation in the pyrolysis furnace.

[0049] In order to make the sealing gas flow into the furnace in one direction and reduce the consumption of sealing gas, an annular empty warehouse structure is formed by the outer wall of the dynamic sealing structure, the upper pressure cover plate 109, the outer cover plate 110 and the outer wall of the rotary pyrolysis furnace, and the graphite filler is placed in the annular empty warehouse structure to fill it up to form a graphite filler warehouse 111. The graphite filler warehouse 111 is used to block the axial gap at the outermost end of the dynamic sealing structure; the outer wall of the dynamic sealing structure, the outer cover plate 110 and the upper pressure cover plate 109 are respectively connected by bolts. When the axial gap between the dynamic ring seal 106 and the static ring seal 105 is adjusted, the dynamic sealing structure drives the upper pressure cover plate 109 and the outer cover plate 110 to move to adjust the pressure strength of the graphite filler, ensure the sealing effect, and thus achieve zero leakage of the sealing gas in the dynamic sealing structure.

[0050] The rubber flexible sealing structure 1 is formed by overlapping a rubber sheet connecting plate 112, a support plate 113, and a staggered rubber sheet 114. The rubber sheet connecting plate 112 is fixed to the outer wall of the outer cover plate 110, and the support plate 113 is welded and fixed to the furnace body 3 of the rotary pyrolysis furnace. The two ends of the staggered rubber sheet 114 are respectively connected to the rubber sheet connecting plate 112 and the support plate 113 by steel wire binding, and a corresponding annular flexible sealing state is formed between the three components. The rubber sheet connecting plate 112 is made by bending a steel ring; with the bending part as the boundary, the outer side edge of the steel ring is tightly attached to the outer wall of the outer cover plate 110 and connected by bolts, and the inner side edge of the steel ring forms an angle α with the outer cover plate 110, and α is 1-90°. In the first multi-layer composite sealing structure, the compacted fillers of the pressure cover plate 209 and the outer cover plate 110 are thinned due to the wear of graphite during the rotation of the rotary pyrolysis furnace, and a rubber flexible sealing structure is set to further increase the effective service life of the sealing structure.

[0051] By implementing the above first-layer multi-layer composite sealing structure, the sealing between the rotary pyrolysis furnace and the feed furnace cover or the discharge furnace cover can be achieved, thereby realizing positive pressure operation in the rotary pyrolysis furnace.

[0052] The second multi-layer composite sealing structure acts between the outer jacket sleeve and the rotary pyrolysis furnace, and is provided with a second insulation chamber 202, a second dynamic sealing structure, a graphite packing ring, a second elastic corrugated structure, and a rubber flexible sealing structure in sequence from inside to outside along the axial direction of the rotary pyrolysis furnace.

[0053] The second heat insulation chamber 202 is arranged between the furnace body of the rotary pyrolysis furnace and the outer jacket sleeve. The second heat insulation chamber 202 is connected to the outer jacket sleeve as a whole. There is a reserved gap between the second heat insulation chamber 202 and the outer wall of the furnace body of the rotary pyrolysis furnace. The thickness of the chamber wall of the second heat insulation chamber 202 is 2-20mm. The interior of the second heat insulation chamber 202 is a vacuum environment with a vacuum degree of 80-100kpa. The second heat insulation chamber 202 can effectively reduce the heat dissipation of the pyrolysis furnace outward. When the outer jacket sleeve is operated under positive pressure, the high-temperature gas in the sleeve first passes through the second heat insulation chamber 202. The second heat insulation chamber 202 can effectively reduce the heat dissipation of the high-temperature gas in the sleeve outward.

[0054] The second heat insulation chamber 202 is also an empty chamber type annular structure, and the cross section of the second heat insulation chamber 202 is a rectangle, and the length and width of the cross section are respectively: L2=(φ2-Φ) / 2-C2, W2=1 / 2L2 Among them, L2 is the length of the section, φ2 is the inner diameter of the outer jacket sleeve, Φ is the outer diameter of the rotary pyrolysis furnace, C2 is the reserved gap, and the second reserved gap is 2-10mm; W2 is the width of the section.

[0055] The dynamic seal structure 2 includes a static ring seal 205, a dynamic ring seal 206, a gas seal gas inlet 207, and a gas seal gas outlet pressure port 208. The dynamic ring seal 206 is welded and fixed on the rotary pyrolysis furnace body 3. The static ring seal 205 and the outer jacket sleeve cover plate 201 are connected and fixed by bolts. There is a toothed bite structure between the dynamic ring seal 206 and the static ring seal 205. There is a radial gap and an axial gap between the dynamic ring seal 206 and the static ring seal 205. The radial gap is 1-20mm. The axial initial installation gap between the dynamic ring seal 206 and the static ring seal 205 is 1-40mm. The axial gap between the dynamic ring seal 206 and the static ring seal 205 is adjusted by the expansion and contraction of the elastic corrugated structure. The axial gap is adjusted so that the dynamic ring seal 206 and the static ring seal 205 work together, and the positive pressure zero leakage operation of the outer jacket sleeve of the pyrolysis furnace is realized through the dynamic seal structure 2.

[0056] Inner and outer graphite packing rings 212 are arranged between the outer end face of the dynamic sealing structure 2 and the pressure cover plate 209; the inner graphite packing ring 211 is formed by the outer end face of the dynamic sealing structure 2 and the pressure cover plate 209 pressing the graphite packing; the outer end face of the dynamic sealing structure 2 and the surface of the pressure cover plate 209 are respectively provided with corresponding annular grooves, and the graphite packing is filled and pressed between the two annular grooves to form an outer graphite packing ring 212; the compaction degree of the graphite packing is adjusted by the expansion and contraction degree of the elastic corrugated structure.

[0057] The elastic corrugation structure 2 includes an elastic corrugation 204, a pull rod 203 and a fixed plate 210. The two ends of the elastic corrugation 204 are respectively welded to the pressure cover plate 209 and the fixed plate 210. The pull rod 203 is installed between the pressure cover plate 209 and the fixed plate 210 by bolt connection. The expansion and contraction amount of the elastic corrugation 204 can be adjusted by adjusting the tightness of the nut of the pull rod 203.

[0058] The rubber flexible sealing structure includes a rubber sheet connecting plate 213, a support plate 214, and a staggered rubber sheet 215. The rubber sheet connecting plate is fixed on the pressure cover plate 209, and the support plate is fixedly welded on the upper surface of the static ring. The two ends of the staggered rubber sheet are respectively connected to the rubber sheet connecting plate and the support plate by steel wire binding, and the three components are overlapped to form a rubber flexible sealing effect. The rubber sheet connecting plate is made by bending an L-shaped steel ring, which is bounded by two bending points. The outer ring part of the steel ring is tightly attached to the outer wall of the pressure cover plate 209 and connected by bolts. The middle part of the steel ring is perpendicular to the pressure cover plate 209, and the inner ring part of the steel ring is bent toward the rotary pyrolysis furnace. The angle between the middle part and the inner ring part of the steel ring is β, and the value of β is 91-179°.

[0059] In the second multi-layer composite sealing structure, the flow resistance of the high-temperature gas in the furnace to the outside of the furnace can be increased by setting a dynamic sealing structure. Through the automatic adjustment of the dynamic sealing gas seal pressure and flow, a small amount of cold air is introduced into the furnace to effectively isolate the high-temperature gas from flowing outward. The gap between the dynamic and static ring seals caused by the thermal expansion of the furnace body can be adjusted by the pull rod of the elastic corrugated structure 2 to adjust the elastic corrugation expansion. The deformation of the elastic corrugation squeezes the high-temperature graphite filler and compacts the high-temperature graphite filler, so that the gas seal gas in the dynamic sealing structure 2 forms a unidirectional flow, reducing the leakage and consumption of the gas seal gas to the outside. The high-temperature graphite filler is worn and thinned during the rotation of the rotary pyrolysis furnace. The rubber flexible sealing structure is set to further increase the effective service life of the sealing structure. At the same time, the staggered rubber sheets 114 and 114 are both composed of three layers of rubber sheets arranged in staggered layers, and the gas seal gas is air or nitrogen.

[0060] By implementing the second multi-layer composite sealing structure, the sealing between the rotary pyrolysis furnace and the outer jacket sleeve can be achieved, thereby achieving positive pressure operation in the outer jacket of the rotary pyrolysis furnace.

[0061] After adopting the composite sealing device, the process of the rotary pyrolysis furnace entering operation is as follows: (1) When the pyrolysis furnace is slowly heated up and started, the temperature inside the furnace rises, and the gas expands, causing the pressure inside the furnace to rise. At this time, the gas seal gas regulating valve configured in the first multi-layer composite sealing structure automatically opens, and controls the pressure of the gas seal gas outlet pressure port 108 to be greater than the pressure inside the furnace. The pressure difference between the gas seal gas outlet pressure port 108 and the pressure inside the furnace is controlled between 0-10kPa, so that the high-temperature gas in the furnace will not leak to the gas seal side.

[0062] (2) When a fixed amount of high-temperature gas is introduced into the outer jacket sleeve to heat the furnace body, the pressure inside the sleeve gradually rises as the temperature inside the sleeve rises. At this time, the gas seal gas regulating valve configured in the second multi-layer composite sealing structure automatically opens, and controls the pressure of the gas seal gas outlet pressure port 208 to be greater than the pressure inside the sleeve. The difference between the pressure of the gas seal gas outlet pressure port 208 and the pressure inside the sleeve is controlled between 0-10kPa, so that the high-temperature gas in the sleeve will not leak to the gas seal side.

[0063] (3) When the rotary pyrolysis furnace is heated to the operating temperature, materials containing organic matter are put in. The organic matter in the materials is decomposed into small molecular organic gas under high temperature. When the amount of materials put in gradually increases, the gas volume in the furnace gradually increases, and the pressure in the furnace increases. When the pressure in the furnace increases, the gas seal gas regulating valve automatically opens and controls the pressure of the gas seal gas outlet pressure port 108 to be greater than the pressure in the furnace. The difference between the gas seal gas outlet pressure port 108 and the pressure in the furnace is controlled between 0-10kpa, so that the high-temperature organic gas in the furnace will not leak to the gas seal side.

[0064] (4) When the pyrolysis furnace is shut down, the material input is gradually reduced, the gas volume in the furnace is gradually reduced, and the gas pressure in the furnace is reduced. When the pressure in the furnace is reduced, the gas seal gas regulating valve is gradually closed, and the pressure of the gas seal gas outlet pressure port 108 is controlled to be greater than the pressure in the furnace, and the pressure difference between the gas seal gas outlet pressure port and the furnace is controlled between 0-10kpa.

[0065] (5) When the pyrolysis furnace is shut down, the amount of material in the furnace is reduced. At this time, it is necessary to reduce the amount of high-temperature gas in the heating sleeve to reduce the heating power of the heating sleeve on the furnace body to avoid overheating in the furnace. At this time, the pressure in the heating sleeve gradually decreases, the gas seal gas regulating valve is gradually closed, and the pressure at the gas seal gas outlet pressure port 208 is controlled to be greater than the pressure in the furnace. The difference between the pressure at the gas seal gas outlet pressure port 208 and the pressure in the sleeve is controlled between 0-10kpa.

[0066] By automatically controlling the pressure in the above steps, the positive pressure regulation of the pyrolysis furnace or the outer jacket sleeve can be fully achieved.

Claims

1. A composite sealing device for positive pressure of an externally heated jacketed rotary pyrolysis furnace, characterized in that: A double multi-layer composite sealing structure is provided on the rotary pyrolysis furnace: the first multi-layer composite sealing structure is provided between the feeding / discharging furnace cover and the rotary pyrolysis furnace, and is used to realize positive pressure operation in the rotary pyrolysis furnace; the second multi-layer composite sealing structure is provided between the outer jacket sleeve and the rotary pyrolysis furnace, and is used to realize high temperature positive pressure operation of the outer jacket sleeve (2); The first-layer multi-layer composite sealing structure comprises a heat-insulating bin (102), an elastic corrugated structure, a dynamic sealing structure, a graphite filler bin (111), and a rubber flexible sealing structure, which are sequentially arranged along the axial direction of the rotary pyrolysis furnace; the heat-insulating bin (102) is located between the inner wall of the hood head (1), the inner wall of the furnace cover plate (101), and the outer wall of the rotary pyrolysis furnace, and is an overall hollow bin type annular structure; a reserved gap is provided between the heat-insulating bin (102) and the outer wall of the rotary pyrolysis furnace; the elastic corrugated structure comprises a pull rod (103) and an elastic corrugated structure (104); the pull rod (103) is connected between the furnace cover plate (101) and the dynamic sealing structure by bolts, and the elastic corrugated structure (104) is connected between the furnace cover plate (101) and the dynamic sealing structure by bolts. The two ends of the corrugation (104) are respectively welded to the furnace cover plate (101) and the dynamic sealing structure (1), and the expansion and contraction amount of the elastic corrugation (104) can be adjusted by adjusting the tightness of the nut; the dynamic sealing structure (1) comprises a static ring seal (105), a dynamic ring seal (106), a gas seal gas inlet (107), and a gas seal gas outlet pressure tapping port (108); the dynamic ring seal (106) is welded and fixed to the outer wall of the rotary pyrolysis furnace body (3); the dynamic ring seal (106) rotates along with the rotary pyrolysis furnace body (3); a tooth-shaped bite structure is formed between the dynamic ring seal (106) and the static ring seal (105); the dynamic ring seal (106) and the static ring seal (105) are connected to each other. A radial gap and an axial gap are left between the dynamic sealing structure and the static sealing structure; the size of the axial gap is adjusted by the expansion and contraction of the elastic corrugation; an annular hollow chamber structure is formed by the outer wall of the dynamic sealing structure, the upper pressure cover plate (209), the outer cover plate (110) and the outer wall of the rotary pyrolysis furnace; a graphite filler is placed in the annular hollow chamber structure to fill it up to form a graphite filler chamber (111); the graphite filler chamber (111) is used to block the axial gap at the outermost end of the dynamic sealing structure; the outer wall of the dynamic sealing structure, the outer cover plate (110) and the upper pressure cover plate (209) are respectively connected by bolts, when the axial gap between the dynamic ring seal (106) and the static ring seal (105) is When adjusted, the dynamic sealing structure 1 drives the upper pressure cover plate (209) and the outer cover plate (110) to move so as to adjust the pressure strength of the graphite filler; the flexible sealing structure 1 is formed by overlapping a rubber sheet connecting plate 1 (112), a support plate 1 (113), and a staggered rubber sheet 1 (114); the rubber sheet connecting plate 1 (112) is fixed to the outer wall of the outer cover plate (110); the support plate 1 (113) is welded and fixed to the rotary pyrolysis furnace body (3); the two ends of the staggered rubber sheet 1 (114) are respectively connected to the rubber sheet connecting plate 1 (112) and the support plate 1 (113) by steel wire bundling, and a corresponding annular flexible sealing state is formed between the three components; The second-layer multi-layer composite sealing structure is provided with a second heat insulation chamber (202), a second dynamic sealing structure, a graphite packing ring, a second elastic corrugated structure, and a rubber flexible sealing structure in sequence from the inside to the outside along the axial direction of the rotary pyrolysis furnace; the second heat insulation chamber (202) is arranged between the outer wall of the outer jacket sleeve of the rotary pyrolysis furnace and the inner wall of the outer jacket sleeve, the second heat insulation chamber (202) and the outer jacket sleeve are welded as a whole, and there is a reserved gap between the second heat insulation chamber (202) and the outer wall of the outer jacket sleeve of the rotary pyrolysis furnace; the second dynamic sealing structure includes a second static ring seal (205), a second dynamic ring seal (206), a gas seal gas inlet (207), and a gas seal gas outlet pressure taking device. The rotary pyrolysis furnace body (3) is provided with a second dynamic ring seal (206) welded and fixed thereto, and the static ring seal (205) and the outer jacket sleeve cover plate (201) are connected and fixed thereto by bolts. A tooth-shaped interlocking structure is provided between the dynamic ring seal (206) and the static ring seal (205). A radial gap and an axial gap are left between the dynamic ring seal (206) and the static ring seal (205). The axial gap is adjusted so that the dynamic ring seal (206) and the static ring seal (205) cooperate with each other. An inner ring and an outer ring of graphite packing rings (212) are provided between the outer end surface of the dynamic seal structure (206) and the pressure cover plate (209). The inner graphite packing ring (211) is formed by the outer end face of the dynamic sealing structure 2 and the pressure cover plate (209) pressing the graphite packing; the outer end face of the dynamic sealing structure 2 and the surface of the pressure cover plate (209) are respectively provided with annular grooves corresponding to the positions, and the graphite packing is filled and pressed between the two annular grooves to form an outer graphite packing ring (212); the compaction degree of the graphite packing is adjusted by the expansion and contraction degree of the elastic corrugated structure; the elastic corrugated structure 2 includes an elastic corrugation 2 (204), a pull rod 2 (209) and a fixed plate (210), and the two ends of the elastic corrugation 2 (204) are respectively connected to the pressure cover plate (209), The fixing plate (210) is welded, and the second pull rod (209) is installed between the pressure cover plate (209) and the fixing plate (210) by bolt connection. The expansion and contraction amount of the second elastic corrugation (204) can be adjusted by adjusting the tightness of the nut of the second pull rod (209). The rubber flexible sealing structure includes a second rubber sheet connecting plate (213), a second support plate (214), and a second staggered rubber sheet (215). The rubber sheet connecting plate is fixed on the pressure cover plate (209), and the support plate is fixedly welded on the upper surface of the static ring. The two ends of the staggered rubber sheet are respectively connected to the rubber sheet connecting plate and the support plate by steel wire binding. The three components are overlapped to form a rubber flexible sealing effect.

2. The composite sealing device for positive pressure of external heating jacketed rotary pyrolysis furnace according to claim 1, characterized in that: The cross-section of the heat insulating chamber 1 (102) is rectangular. The side of the heat insulating chamber 1 (102) facing the inside of the rotary pyrolysis furnace is in direct contact with the high-temperature gas in the furnace. The outer annular surface and the outer side surface are respectively closely attached to the inner wall of the hood head (1) and the inner wall of the furnace cover plate (101). The inner annular surface is flush with the inner end surface of the furnace cover plate (101). A reserved gap 1 is formed between the inner annular wall surface, the inner end surface of the furnace cover plate (101) and the outer wall of the rotary pyrolysis furnace.

3. The positive pressure sealing device for an externally heated jacketed rotary pyrolysis furnace according to claim 1 or 2, characterized in that: The length and width of the cross section of the heat insulation chamber 1 (102) are respectively: L1=(φ1-Φ) / 2-C1, W1=1 / 2L1 Among them, L1 is the length of the cross section, φ1 is the inner diameter of the feed furnace cover or the inner diameter of the discharge furnace cover, Φ is the outer diameter of the rotary pyrolysis furnace, C1 is the reserved gap, and the reserved gap is 2-10mm; W1 is the width of the cross section.

4. The composite sealing device for positive pressure of an externally heated jacketed rotary pyrolysis furnace according to claim 1 or 2, characterized in that: The thickness of the wall of the heat-insulating chamber 1 (102) is 2-20 mm, and the interior of the heat-insulating chamber 1 (102) is a vacuum environment with a vacuum degree of 80-100 kPa.

5. The composite sealing device for positive pressure of external heating jacketed rotary pyrolysis furnace according to claim 1, characterized in that: In the dynamic sealing structure 1, one side of the static ring seal 1 (105) is welded and fixed to the elastic corrugation 1 (104), and the other side is bolted to the upper pressure cover plate (209).

6. The composite sealing device for positive pressure of an externally heated jacketed rotary pyrolysis furnace according to claim 1 or 6, characterized in that: The radial clearance between the dynamic ring seal 1 (106) and the static ring seal 1 (105) is 1-20 mm, and the axial initial installation clearance between the dynamic ring seal 1 (106) and the static ring seal 1 (105) is 1-40 mm.

7. The composite sealing device for positive pressure of an externally heated jacketed rotary pyrolysis furnace according to claim 1, characterized in that: The upper pressure cover plate (209) is a concave structure, and the two raised outer side walls of the concave structure are respectively connected to the dynamic ring seal (106) and the outer side cover plate (110) by bolts. The adjusting bolts drive the outer side cover plate (110) to compact the graphite filler, thereby achieving zero leakage of the gas seal in the dynamic sealing structure.

8. The composite sealing device for positive pressure of external heating jacketed rotary pyrolysis furnace according to claim 1, characterized in that: The rubber sheet connecting plate 1 (112) is made by bending a steel ring; with the bending portion as the boundary, the outer edge of the steel ring is tightly attached to the outer wall of the outer cover plate (110) and connected by bolts, and the inner edge of the steel ring and the outer cover plate (110) form an angle α, and α is 1-90°.

9. The composite sealing device for positive pressure of external heating jacketed rotary pyrolysis furnace according to claim 1, characterized in that: For the first-layer multi-layer composite sealing structure, a gas regulating valve is set at the gas sealing gas inlet (107) to control the gas sealing gas flow rate; a pressure transmitter is set at the gas sealing gas outlet pressure port (108) to measure the gas sealing gas outlet pressure, and the measured gas sealing gas outlet pressure is interlocked with the pressure inside the rotary pyrolysis furnace and the gas sealing gas inlet regulating valve; after the dynamic sealing structure is allowed to move and work, when the pressure inside the rotary pyrolysis furnace is greater than the gas sealing gas outlet pressure, the gas sealing gas inlet regulating valve automatically opens the gas sealing gas flow rate at the atmospheric gas sealing inlet; when the pressure inside the rotary pyrolysis furnace is less than or equal to the gas sealing gas outlet pressure, the gas sealing gas inlet regulating valve remains unchanged.

10. The composite sealing device for positive pressure of external heating jacketed rotary pyrolysis furnace according to claim 1, characterized in that: The second heat insulation chamber (202) is an empty chamber type annular structure. The cross section of the second heat insulation chamber (202) is a rectangle. The length and width of the cross section are respectively: L2=(φ2-Φ) / 2-C2, W2=1 / 2L2 Among them, L2 is the length of the section, φ2 is the inner diameter of the outer jacket sleeve, Φ is the outer diameter of the rotary pyrolysis furnace, C2 is the reserved gap, and the second reserved gap is 2-10mm; W2 is the width of the section.

11. The composite sealing device for positive pressure of an externally heated jacketed rotary pyrolysis furnace according to claim 1 or 10, characterized in that: The thickness of the wall of the second heat-insulating chamber (202) is 2-20 mm, and the interior of the second heat-insulating chamber (202) is a vacuum environment with a vacuum degree of 80-100 kPa.

12. The composite sealing device for positive pressure of an externally heated jacketed rotary pyrolysis furnace according to claim 1 or 10, characterized in that: In the dynamic sealing structure 2, the radial clearance between the dynamic ring seal 2 (206) and the static ring seal 2 (205) is 1-20 mm, and the axial initial installation clearance between the dynamic ring seal 2 (206) and the static ring seal 2 (205) is 1-40 mm; the axial clearance between the dynamic ring seal 2 (206) and the static ring seal 2 (205) is adjusted by the expansion and contraction of the elastic corrugated structure.

13. The composite sealing device for positive pressure of external heating jacketed rotary pyrolysis furnace according to claim 1, characterized in that: The rubber sheet connecting plate is made by bending an L-shaped steel ring, which is bounded by two bending points. The outer ring part of the steel ring is tightly attached to the outer wall of the pressure cover plate (209) and connected by bolts. The middle part of the steel ring is perpendicular to the pressure cover plate (209), and the inner ring part of the steel ring is bent toward the rotary pyrolysis furnace. The angle between the middle part of the steel ring and the inner ring part is β, and the value of β is 91-179°.

14. The composite sealing device for positive pressure of external heating jacketed rotary pyrolysis furnace according to claim 1, characterized in that: For the second-layer multi-layer composite sealing structure, gas-sealing gas is introduced, and a gas regulating valve is set at the second gas-sealing gas inlet (207) to control the gas-sealing gas flow rate; a pressure transmitter is set at the second gas-sealing gas outlet pressure port (208) to measure the gas-sealing gas outlet pressure, and the measured gas-sealing gas outlet pressure is interlocked with the pressure inside the outer casing of the rotary pyrolysis furnace and the gas regulating valve at the second gas-sealing gas inlet (207); when the pressure inside the rotary pyrolysis furnace is greater than the gas-sealing gas outlet pressure, the gas-sealing gas inlet regulating valve automatically opens the atmospheric gas-sealing gas inlet flow rate, and when the pressure inside the rotary pyrolysis furnace is less than or equal to the gas-sealing gas outlet pressure, the gas regulating valve at the second gas-sealing gas inlet (207) remains unchanged.

15. The composite sealing device for positive pressure of external heating jacketed rotary pyrolysis furnace according to claim 1, characterized in that: The staggered-layer rubber sheet one (114) and the staggered-layer rubber sheet two (215) are both composed of three layers of rubber sheets arranged in staggered layers.

16. The composite sealing device for positive pressure of external heating jacketed rotary pyrolysis furnace according to claim 1, characterized in that: The sealing gas in the double multi-layer composite sealing structure is air or nitrogen.

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