Rotary fire grate device of biomass gasifier

Abstract

The utility model discloses a rotary fire grate device of a biomass gasification furnace, which relates to the technical field of gasification furnace accessories and comprises three layers of fire grate rings arranged in a tower shape, the bottoms of the three layers of fire grate rings are fixedly connected with the top of a supporting ring through bolts, and the bottom of the supporting ring is embedded between a large gear and an outer bearing sleeve and connected with the large gear and the outer bearing sleeve through key grooves and bolts. A lower supporting plate and an upper supporting plate are sequentially arranged at the top of the supporting body, a hollow supporting base is arranged at the bottom of the supporting body, the lower supporting plate, the supporting plate and the supporting base are fixedly connected through bolts, the top of the supporting plate is sleeved with an inner bearing sleeve and fixed through bolts, and a plurality of ash discharging cutters are arranged on the circumferential sides of the three layers of fire grates. An inclined dustproof protection plate is arranged at the bottom of the top plate of the supporting ring, a dust bearing table is further arranged between the dustproof protection plate and the ash discharging cutter, a dustproof cover with a zigzag-shaped section is further arranged at the bottom of the dustproof protection plate, the dust bearing table and the dustproof cover are fixedly connected with the supporting bottom plate, and a downward ash discharging channel is formed among the dust bearing table, the ash discharging cutter, the dustproof protection plate and the dustproof cover. The device is reasonable in structural design, good in gas distribution and slag breaking effect, convenient to install and regulate speed, and stable in operation of the gasification furnace.

Description

Technical Field

[0001] The utility model belongs to the technical field of biomass energy, and in particular relates to a rotating grate device of a biomass gasification furnace. Background Art

[0002] Biomass energy is a clean and renewable energy source with combustion characteristics similar to fossil fuels. It is renewable and has zero carbon emissions. It is one of the most promising new energy sources to replace oil in the future. In the biomass gasification process, biomass particles are put in from the top furnace mouth. Due to the uneven biomass particles or uneven gas distribution of the gasifier, it is very easy to form large slag blocks during the gasification process. On the one hand, the formed slag blocks have a high coke content, and the biomass is not fully burned, resulting in a large energy loss. On the other hand, the slag blocks accumulate on the grate ring, and the slag layer gradually rises, blocking the ash channel, making it difficult to discharge the slag and the gasifier difficult to operate stably.

[0003] At present, the main problems of the relevant biomass gasifier rotary grate devices on the market are unreasonable structural design, complex process, easy accumulation of slag layer, low thermal efficiency of gasifier, unstable operation, etc. Therefore, it is very necessary to develop a biomass gasifier rotary grate device with uniform gas distribution, strong slag breaking and slag discharge capacity, stable operation, energy saving and emission reduction. Summary of the invention

[0004] The utility model aims to provide a biomass gasifier rotary grate device, which has a reasonable structural design, good gas distribution and slag breaking and slag discharge effects, and improves the thermal efficiency and operation stability of the biomass gasifier.

[0005] In order to achieve the above purpose, the technical solution adopted by the utility model is:

[0006] A biomass gasification furnace rotary grate device, the grate is a three-layer grate ring arranged in a tower shape, the three-layer grate ring is fastened to the upper part of the support ring by bolts, the support ring is respectively connected to the large gear and the outer bearing sleeve by keyways and bolts, the upper support plate is connected to the lower part of the large gear by keyways, so that the three-layer grate ring, the support ring, the upper support plate, the large gear and the outer bearing sleeve are relatively fixed; it also includes an internally hollow support body, the support body is fastened to the support bottom plate and the lower support plate by bolts, and the support body is fastened to the inner bearing sleeve by bolts, so that the support bottom plate, the support body, the lower support plate and the inner shaft The bearing sleeve is relatively fixed; a plurality of ash discharge knives are arranged on the circumferential side of the three-layer grate ring to gather the slag inward on the ash supporting platform; an anti-ash guard plate is welded on the lower part of the supporting ring, the anti-ash guard plate is inclined, an ash supporting platform is also provided between the anti-ash guard plate and the ash discharge knife, an ash supporting platform is also provided, and an ash protection cover with a folded cross-section is also provided at the bottom of the anti-ash guard plate, so that a downward ash discharge channel is formed between the ash supporting platform, the ash discharge knife, the anti-ash guard plate and the ash protection cover. The equipment operates normally through gear meshing, driving the three-layer grate ring to rotate, and the horizontal friction surface and the vertical friction surface are respectively the two contact surfaces of the upper supporting plate, the lower supporting plate and the inner bearing sleeve and the outer bearing sleeve.

[0007] Furthermore, the three-layer grate ring is cast as one piece, and six of the above-mentioned slag-breaking ribs are arranged circumferentially above the second-layer grate ring and the third-layer grate ring; the slag-breaking ribs and the corresponding grate ring are cast at one time, and the slag-breaking ribs are evenly arranged and protrude upward in the radial direction, with a thickness of 10 mm and a height corresponding to the height of the grate ring; there are three annular air distribution ports evenly distributed in the gaps between adjacent grate layers.

[0008] Furthermore, the ash discharge knives are connected to the circumferential side of the three-layer grate by welding, extending and protruding outward, and there are four of them, forming an angle of 15° with the radial direction and evenly arranged in the circumferential direction, which can meet the requirement of reverse rotation of the grate.

[0009] Furthermore, an anti-ash guard plate is welded to the lower part of the support ring to block the slag falling from the ash support platform.

[0010] Furthermore, the ash protection cover is placed on the supporting base to form a maze passage with the ash protection plate to prevent slag from entering the transmission part.

[0011] Furthermore, the full load power of the rotary grate drive motor is not less than 0.22 kW, and the operating speed range of the three-layer grate ring is 0-60 r / h.

[0012] Furthermore, the support ring material is made of heat-resistant steel, and the three-layer grate ring and ash discharge knife material are made of heat-resistant steel.

[0013] The utility model has the advantages that the rotating grate device of the biomass gasifier can make the slag turn over back and forth through the three-layer grate ring and the ash discharge knife, which is beneficial to the crushing and discharge of the slag and maintains the stable operation of the gasifier. At the same time, the contact area between the slag and the three-layer grate ring and the gasifier is increased, so that the raw materials can be fully cracked and fully burned, the carbon content of the slag is reduced, the thermal efficiency of the biomass gasifier is improved, and the obtained gasification gas has high calorific value and low tar content. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic diagram of the structure of the utility model. DETAILED DESCRIPTION Example

[0015] like Figure 1 As shown, a rotating grate device for a biomass gasification furnace, the grate is a three-layer grate ring 9 arranged in a tower shape. The three-layer grate ring 9 is fastened to the upper part of the support ring 6 by bolts. The support ring 6 is connected to the large gear 5 and the outer bearing sleeve 7 by keyways and bolts respectively, and the upper support plate 4 is connected to the lower part of the large gear 5 by keyways, so that the three-layer grate ring 9, the support ring 6, the upper support plate 4, the large gear 5 and the outer bearing sleeve 7 are relatively fixed. The support body 2 is fastened to the support bottom plate 1 and the lower support plate 3 by bolts, and the support body 2 is fastened to the inner bearing sleeve 8 by bolts, so that the support bottom plate 1, the support body 2, the lower support plate 3 and the inner bearing sleeve 8 are relatively fixed. A plurality of ash discharge knives 12 are arranged on the circumference of the three-layer grate ring 9 to gather the slag inward on the ash support platform 13. The ash protection plate 14 is welded to the lower part of the support ring 6, so that a downward ash discharge channel is formed between the ash support platform 13, the ash discharge knife 12, the ash protection plate 14 and the ash protection cover 15, and the ash support platform and the ash protection cover are fixedly connected to the support bottom plate. The equipment operates normally through gear meshing, driving the three-layer grate ring 9 to rotate, and the horizontal friction surface and the vertical friction surface are the two contact surfaces of the upper support plate 4, the lower support plate 3 and the inner bearing sleeve 8, and the outer bearing sleeve 7.

[0016] In this embodiment, the three-layer grate ring 9 is cast as one piece, and six slag-breaking ribs 10 are arranged circumferentially above the second-layer grate ring and the third-layer grate ring. The slag-breaking ribs 10 are cast and formed with the corresponding grate ring at one time, and the slag-breaking ribs 10 are uniformly arranged and protrude upward in the radial direction, and the thickness is 10 mm, and the height is adapted to the height of the grate ring. There are three annular air distribution ports 11 uniformly arranged in the gaps between adjacent grate layers. The ash discharge knives 12 are connected to the peripheral side of the three-layer grate ring 9 by welding, extending outward and protruding, and there are four of them, which are at an angle of 15° with the radial direction and are uniformly arranged circumferentially to meet the requirements of reverse rotation of the grate. The ash-proof guard plate 14 is welded to the lower part of the support ring 6 to block the slag falling from the ash-bearing platform 13. The ash-proof cover 15 is placed on the support bottom plate 1, and forms a maze passage with the ash-proof guard plate 14 to prevent the slag from entering the transmission part. The full load power of the rotating grate drive motor is controlled to be not less than 0.22kw, and the working speed range of the three-layer grate ring 9 is 0-60 r / h. The material of the support ring 6 is heat-resistant steel, and the material of the three-layer grate ring 9 and the ash discharge knife 12 is heat-resistant steel.

[0017] The working process of the rotary grate device of the biomass gasifier in this embodiment is as follows:

[0018] The three-layer grate ring 9 is in a rotating state during the operation of the equipment. To realize the rotation of the three-layer grate ring 9, the engagement between the small gear of the motor and the large gear 5 can drive the support ring 6 and the three-layer grate ring 9 to rotate. During the normal operation of the equipment, the horizontal friction surface and the vertical friction surface are the two contact surfaces of the upper support plate 4, the lower support plate 3 and the inner bearing sleeve 8 and the outer bearing sleeve 7 respectively. A slag layer of about 30mm~50mm is retained on the top of the three-layer grate ring 9 to prevent the biomass from burning directly on the grate. The slag breaking ribs 10 on the second and third grate rings protrude upward to stir the slag, increase the contact area with the gasifier, and fully burn the biomass. An ash discharge knife 12 is provided on the circumferential side of the third-layer grate ring to squeeze and crush the large pieces of slag, and discharge the slag downward from the four sides of the furnace body through the ash discharge channel formed between the ash support platform 13, the ash protection plate 14 and the ash protection cover 15, so as to maintain a certain slag layer height and ensure the stable operation of the gasifier. The gasifying agent rises from the furnace bottom along the hollow axis of the support body 2, enters the cavity formed by the three-layer grate ring 9, reduces the gas velocity, increases the static pressure, and then flows into the furnace through the annular gas distribution port 13 in the gap between the two adjacent layers of the grate through the gaps between the layers of the grate, and uniformly contacts the slag along the end face of the gasifier. When the gasifying agent flows through the grate cavity, the grate is cooled to reduce the grate temperature and extend the service life of the grate. The rotating grate device of the biomass gasifier in this embodiment allows the biomass to be fully burned, has good gas distribution and slag breaking and slag removal effects, has a reasonable equipment structure, is easy to operate, and the gasifier runs stably.

Claims

1. A biomass gasification furnace rotary grate device, characterized in that: The top of the support body is provided with a lower support plate and an upper support plate in sequence, the upper support plate is fixedly arranged in the keyway at the bottom of the large gear, and the lower support plate is located in the keyway at the top of the support body, and a hollow supporting base is provided at the bottom of the supporting body, and the lower support plate, the support plate and the supporting base are fixedly connected by bolts, the top outer sleeve of the support plate is provided with an inner bearing sleeve and fixed by bolts, a plurality of ash discharge knives are provided on the circumferential side of the three-layer grate ring, an inclined ash protection plate is provided at the bottom of the support ring top plate, an ash supporting platform is also provided between the ash protection plate and the ash discharge knife, and an ash protection cover with a folded cross-section is also provided at the bottom of the ash protection plate, the ash protection cover is fixedly connected to the supporting bottom plate, and a downward ash discharge channel is formed between the ash protection platform, the ash discharge knife, the ash protection plate and the ash protection cover.

2. The biomass gasification furnace rotary grate device according to claim 1, characterized in that: The three-layer grate ring is formed by integral casting, and six slag-breaking ribs are arranged circumferentially above the second-layer grate ring and the third-layer grate ring. Three annular air distribution ports are evenly arranged in the gap between adjacent grate layers. The slag-breaking ribs and the corresponding grate rings are formed by casting at one time, and the slag-breaking ribs are evenly arranged radially to protrude upward, and the thickness is 10 mm.

3. The biomass gasification furnace rotary grate device according to claim 2, characterized in that: There are four ash discharge knives, which are welded to the circumferential side of the three-layer grate and extend outward, forming an angle of 15° with the radial direction and are evenly arranged in the circumferential direction.

4. The biomass gasification furnace rotary grate device according to claim 3, characterized in that: The support ring is made of heat-resistant steel, and the three-layer grate ring and the ash discharge knife are made of heat-resistant steel.

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