An equipment for drying biogas residue

Abstract

The present invention discloses a biogas residue drying and processing device, belonging to the technical field of drying equipment. The biogas residue drying and processing device includes a main body, and the main body includes a feeding section, a working section and a discharging section. A skin is provided on the outer sides of the feeding section, the working section and the discharging section; the drying belt is wound through and arranged in the main body, the drying belt has mesh holes, and the drying belt divides the internal space of the main body into an upper contact area and a lower air return area up and down. Through the settings of the main body, the drying belt, the feeder, the negative pressure fan and the air heat exchanger, biogas residues with different humidities are leveled by the feeder on the drying belt with different thicknesses, and on the premise of ensuring the consistency of the discharging humidity, the drying adaptability of the equipment is improved. Then, the air inlet path is optimized through the air heat exchanger, so that the hot air is first blown to the side of the drying belt far away from the negative pressure fan, and then attracted forward by the negative pressure of the negative pressure fan, and the hot air coverage of the entire drying belt is completed with a shorter path.

Description

Technical Field

[0001] The present invention belongs to the technical field of drying equipment, and particularly relates to a marsh residue drying and processing device. Background Art

[0002] The marsh residue drying and processing device is applicable to the drying of wet marsh residue after solid-liquid separation in biogas projects, wet sludge in sewage treatment systems, and wastes such as chicken manure and cow manure. In the specific processing scenario using a belt-type marsh residue drying device, a heat source needs to be connected to evaporate water vapor.

[0003] The existing Chinese utility model patent with the publication number CN204313616U discloses a marsh residue dryer that uses a mesh belt to drive the marsh residue above the heat source. However, in actual use, the design of multiple mesh belts results in a lower hot air temperature and higher humidity at the position of the upper mesh belt, so that the hot air temperature that the marsh residue in the upper mesh belt can contact is lower, and even the phenomenon of secondary condensation of water vapor in the upward airflow in the low-temperature marsh residue in the upper layer occurs. This multi-layer distribution of the mesh belt leads to poor drying consistency of the marsh residue and also significantly increases the drying time. In view of this, a marsh residue drying and processing device is provided to solve the above problems. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to overcome the above-mentioned disadvantages of the prior art and provide a marsh residue drying and processing device.

[0005] The technical solution adopted to solve the above technical problem is as follows:

[0006] A marsh residue drying and processing device includes:

[0007] A main body, the main body includes a feeding section, a working section, and a discharging section, the feeding section, the working section, and the discharging section are arranged in sequence end to end, and a skin is provided on the outer sides of the feeding section, the working section, and the discharging section;

[0008] A drying belt, the drying belt is spirally wound through the main body, the drying belt has mesh holes, and the drying belt divides the internal space of the main body into an upper contact area and a lower return air area;

[0009] A feeder, the feeder is installed on the feeding section in a liftable manner, and the feeder spreads marsh residue with different thicknesses on the upper surface of the drying belt;

[0010] A negative pressure fan, the negative pressure fan is fixed on the vertical side wall of the working section, and the negative pressure fan continuously extracts the air in the contact area and the return air area;

[0011] Air heat exchanger, the air heat exchanger has a thin-walled plate filled with hot water, an outer shell is sleeved outside the thin-walled plate, the outer shell is communicated with the contact area, fins are arranged on the outer wall of the thin-walled plate, and the lower ends of the fins are inclined away from the negative pressure fan so that the incoming air is attracted by the negative pressure fan and crosses the drying belt.

[0012] Furthermore, the working section includes a carrier frame, the carrier frame is fixed at the bottom surface of the working section, the carrier frame is arranged below a part of the drying belt located inside the working section, and the carrier frame is in sliding contact with the drying belt.

[0013] Through the above technical solution, to ensure that the drying belt passes horizontally, the carrier frame supports a part of the drying belt located inside the working section, ensuring the flatness of the drying belt, and thus the thickness of the feed can be controlled.

[0014] Furthermore, a lifting structure is arranged below the feeder, the lifting structure is fixedly connected to the top surface of the feeding section, a distributor is arranged at the outlet of the feeder, the distributor has a plurality of outlets, a flattening member is arranged at the outlet of the distributor, and a material passing space is left between the bottom surface of the flattening member and the top surface of the drying belt.

[0015] Through the above technical solution, to adapt to biogas residues with different humidities, when the biogas residues are wet, the lifting structure lowers the height of the feeder, reduces the material passing space between the bottom surface of the flattening member and the top surface of the drying belt, reduces the thickness of the biogas residues, and disperses the feed through the distributor and flattens it through the flattening member to prevent incomplete drying caused by uneven stacking during drying. When the biogas residues are dry, the height of the feeder can be increased to increase the amount of biogas residues entering per unit time and improve the drying efficiency.

[0016] Furthermore, support rollers are arranged on the upper part of the carrier frame, the support rollers are in rolling contact with the lower surface of a part of the drying belt located inside the working section, and support hairs are installed on the circumferential side wall of the support rollers along the tangent direction, and the support hairs can be inserted and pulled out of the mesh holes from bottom to top when the support rollers rotate.

[0017] Through the above technical solution, to improve the dehydration speed of the biogas residues on the drying belt, the support rollers lift the drying belt and support it by rolling, reducing wear. The support hairs can also be inserted into the mesh holes to lift the biogas residues above the drying belt upward, making the biogas residues fluffy to prevent caking and keeping the mesh holes unblocked, so that the hot air can pass through the stacked biogas residues more smoothly and evenly.

[0018] Furthermore, the working section includes a keel, a top frame connected to the air heat exchanger is arranged at the top of the keel, a side frame connected to the negative pressure fan is arranged on the vertical side wall of the keel, guide rails symmetrically arranged on both sides of the drying belt are fixed inside the keel, the position of the guide rails is higher than that of the side frame, and the guide rails are in sliding contact with the vertical side walls of the drying belt.

[0019] Through the above technical solution, the structure of the working section is optimized, the structural strength is enhanced by the keel, the top air intake is carried out through the top frame, the horizontal exhaust is set through the side frame, the guide rail limits the drying belt, and it can also prevent the biogas residue from falling. The guide rail is narrow at the top and wide at the bottom to play a role in air diversion, so that the hot air blown on the rear side wall of the skin can flow forward, and finally pass through the biogas residue and the drying belt from top to bottom to complete drying.

[0020] Furthermore, a ridger is connected to the keel. The ridger is arranged above a part of the drying belt located inside the working section. The ridger includes a first actuator and a second actuator, and the first actuator and the second actuator can successively form ridged furrows at different positions of the biogas residue.

[0021] Through the above technical solution, to ensure that the deep biogas residue liquid can fully contact the hot air flow, the ridger rotates, and the flat biogas residue is formed into parallel ridged furrows along the traveling direction through the support arm. Moreover, the first actuator and the second actuator are arranged in sequence, and the support arms of the first actuator and the second actuator are arranged in a front-back staggered manner. The first actuator forms ridged furrows in the flat biogas residue, and the second actuator forms ridged furrows again at the raised positions of the biogas residue with ridged furrows and piles the biogas residue to the position of the old ridged furrows, performing alternating turning of the biogas residue to ensure that the biogas residue is fully turned.

[0022] Furthermore, the thin-walled plate adopts a serpentine coiled structure. The thin-walled plate and the fins are arranged in a grid-like staggered manner. Both ends of the thin-walled plate are externally connected to a heat source through a circulating water pipe, and a protective net is arranged above the thin-walled plate.

[0023] Through the above technical solution, to enable the hot air to fully contact the biogas residue on the drying belt, the intake air is separated into multiple independent airflows by the thin-walled plate and the fins. In this way, after intake, the air can be blown more dispersedly onto the vertical inner wall at the rear side of the working section and turn back forward, evenly sweeping over the biogas residue on the drying belt from back to front. The circulating water pipe keeps the thin-walled plate in a stable high-temperature state, avoiding incomplete drying of the biogas residue caused by insufficient heat.

[0024] Furthermore, a drying belt cleaning mechanism is provided on the main body. The drying belt cleaning mechanism includes a spray pipe and a duct. The spray pipe is erected directly above the drying belt. The spray pipe is connected to a flushing pipe through a three-way reversing valve. The flushing pipe is located downstream of the separation of the drying belt and the biogas residue in the discharge section. The duct is connected to the outlet of the negative pressure fan and extends to downstream of the separation of the drying belt and the biogas residue in the discharge section.

[0025] Through the above technical solutions, to improve the continuous operation stability of the equipment and prevent the mesh holes of the drying belt from being blocked by the biogas residue, when not in use, the spray pipe can flush the drying belt. When in use, the spray pipe can also be manually controlled to open to play a fire prevention role. During the drying process, the air duct collects the high-temperature and high-humidity tail gas and guides it to the downstream of the drying belt. After the biogas residue is separated from the drying belt, the drying belt is purged and cleaned, and the tail gas is reasonably utilized. At the same time, before purging, the high-pressure water flow of the flushing pipe can be used to clean the drying belt, and then the high-temperature air flow is used for purging, so that the drying belt can be thoroughly cleaned and quickly dried.

[0026] Further, a waste heat recovery mechanism is provided on the main body. The waste heat recovery mechanism includes an air collecting pipe, which is connected to the outlet of the negative pressure fan. A dehumidifier is provided downstream of the air collecting pipe, and a distribution pipe is installed at the outlet end of the dehumidifier. The distribution pipe is communicated with the air inlet of the air heat exchanger.

[0027] Through the above technical solutions, to optimize the energy consumption of the equipment, during the drying process, after the negative pressure fan draws out the high-temperature and high-humidity tail gas from the working section, it will be concentrated by the air collecting pipe to the position of the dehumidifier. On the premise of ensuring that the waste heat is fully retained, the water vapor in the tail gas is separated, and then the dried tail gas is supplemented to the position of the air heat exchanger through the distribution pipe for secondary heating and circulating drying of the biogas residue.

[0028] Further, a gas selection and circulation mechanism is provided on the main body. The gas selection and circulation mechanism includes a return pipe, which is connected between the outlet of the negative pressure fan downstream and the air inlet of the air heat exchanger upstream. An exhaust pipe is installed at the outlet of the negative pressure fan upstream, and a fresh air pipe is installed at the air inlet of the air heat exchanger downstream.

[0029] Through the above technical solutions, to avoid the influence of the water vapor in the tail gas on the waste heat recovery efficiency, the high-humidity upstream tail gas is directly discharged from the exhaust pipe, and only part of the high-temperature tail gas downstream is re-introduced into the main body through the return pipe for secondary utilization. Moreover, a new drying air source is supplemented by the fresh air pipe, while directly using the waste heat of the untreated tail gas, minimizing the influence of the water vapor in the tail gas on the drying progress as much as possible.

[0030] The beneficial effects of the present invention are as follows:

[0031] Through the setting of the main body, drying belt, feeder, negative pressure fan and air heat exchanger of the present invention, biogas residues with different humidities are spread flat on the drying belt by the feeder with different thicknesses. On the premise of ensuring the consistency of the discharge humidity, the drying adaptability of the equipment is improved. Then, by optimizing the air inlet path of the air heat exchanger, the hot air is first blown to the side of the drying belt away from the negative pressure fan, and then attracted forward by the negative pressure of the negative pressure fan to complete the hot air coverage of the entire drying belt with a shorter path;

[0032] Through the structural optimization of the working section, a carrier is arranged below the drying belt to ensure the drying belt is horizontal, avoid the collapse of the drying belt caused by air pressure difference and the gravity of biogas residue, ensure the stable thickness of the biogas residue, and use the bristles to penetrate the mesh holes of the drying belt from bottom to top to keep the biogas residue fluffy and prevent caking, and prevent the mesh holes from being blocked to ensure the smooth passage of hot air.

[0033] Through the setting of the ridger, when the drying belt drives the biogas residue to move, the first actuator and the second actuator create ridged grooves on the biogas residue, making the biogas residue form multiple corrugated inclined planes that are nearly perpendicular to the direction of hot air flow, greatly increasing the contact area between the hot air and the biogas residue, turning the deep biogas residue to the shallow layer, ensuring uniform drying of the biogas residue layer, and improving the discharge quality. Brief Description of the Drawings

[0034] Figure 1 is the structural schematic diagram of the present invention;

[0035] Figure 2 is the positional schematic diagram between the feeder, the feeding section and the drying belt of the present invention;

[0036] Figure 3 is the structural diagram of the present invention in the state of removing the skin between the feeding section and the working section;

[0037] Figure 4 is the structural schematic diagram of the air heat exchanger of the present invention;

[0038] Figure 5 is the state schematic diagram of the biogas residue in different working sections of the present invention;

[0039] Figure 6 is the structural schematic diagram of the present invention with a drying belt cleaning mechanism added;

[0040] Figure 7 is the sectional schematic diagram of the present invention after adding a drying belt cleaning mechanism;

[0041] Figure 8 is the positional diagram between the discharge section, the drying belt cleaning mechanism and the drying belt of the present invention;

[0042] Figure 9 is the structural schematic diagram of the present invention with a waste heat recovery mechanism added;

[0043] Figure 10 is the structural schematic diagram of one of the carriers in the working section of the present invention;

[0044] Figure 11 is the structural schematic diagram of the present invention with a gas selection and circulation mechanism added.

[0045] Reference numerals: 1, feeder; 11, lifting structure; 12, material distributor; 13, flattening member; 2, feeding section; 21, driving roller; 211, tensioning frame; 22, first rotary reversing roller; 3, working section; 31, skin; 32, contact area; 33, guide rail; 34, return air area; 35, bearing frame; 351, supporting roller; 352, supporting hair; 36, keel; 37, side frame; 38, top frame; 39, ridging tool; 391, first actuator; 392, second actuator; 4, discharging section; 41, discharging port; 42, rotary roller; 43, receiving hopper; 44, second rotary reversing roller; 5, air heat exchanger; 51, housing; 52, thin wall plate; 53, fin; 54, air guide channel; 55, protection net; 56, circulating water pipe; 6, negative pressure fan; 61, air duct; 62, collecting air duct; 63, dehumidifier; 64, air distribution pipe; 65, return pipe; 66, fresh air pipe; 67, waste gas pipe; 7, drying belt; 71, mesh hole; 8, spray pipe; 81, flushing pipe; 9, biogas residue; 91, furrow. Detailed implementation manners

[0046] In order to make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0047] As Figure 1 - Figure 10 shown, this embodiment provides a biogas residue drying and processing device. After the biogas residue 9 undergoes solid-liquid separation, the wet material with a moisture content of about 70% - 80% needs to be dried before it can be further utilized. Specifically, the wet material needs to be evenly spread on the drying belt 7. After the cloth is laid, the wet material is sent into the drying area by moving on the drying belt 7. When the hot air flows through the material layer, the water vapor is carried away by convection. Subsequently, the dry material is collected uniformly, and the tail gas is cooled and then discharged. To overcome the problems existing in the prior art, the actual problem to be solved by this solution is how to ensure that the biogas residue 9 on the drying belt 7 will not be affected by the hot air flow path and show inconsistent drying degrees.

[0048] Specifically, regarding the main body, referring to Figure 1 , the main body includes a feeding section 2, a working section 3 and a discharging section 4. The feeding section 2, the working section 3 and the discharging section 4 are connected end to end and arranged in sequence from left to right. The feeding section 2 is used to input the wet material. A discharging port 41 is provided at the right end of the discharging section 4 to discharge the dry material. Among them, skins 31 are provided on the outer sides of the feeding section 2, the working section 3 and the discharging section 4 to form a box-shaped space and reduce the escape of heat and air flow;

[0049] Regarding the drying belt 7, referring to Figure 2, the drying belt 7 is made of synthetic polyester, has mesh holes 71, and the mesh holes 71 are micro - sieve grids, suitable for fine particles, reducing the spillage of biogas residue 9. The drying belt 7 is arranged in a continuous coiled manner in the main body for circulating feeding. The drying belt 7 divides the internal space of the main body vertically into a contact area 32 and a return air area 34. The biogas residue 9 is located in the contact area 32 and is dried by contacting the hot air entering from above. The tail gas with water vapor will pass downward through the biogas residue 9 and the drying belt 7 and then enter the return air area 34, waiting to be discharged centrally. Specifically, the drying belt 7 is of a two - layer type, one layer is a chain mesh, with sprockets and guide wheels on both sides of the chain mesh for supporting and guiding, and the other layer is a polyurethane mesh belt to prevent the adhesion of biogas residue 9;

[0050] Regarding the feeder 1, the feeder 1 uses a double - helix distributor to ensure the dispersed transportation of the biogas residue 9 onto the drying belt 7. The feeder 1 is installed on the feeding section 2 in a liftable manner, and can adjust the stacking thickness of the biogas residue 9, thereby ensuring the consistency of drying. Specifically, humidity sensors are set at the feeding section 2 and the discharging section 4. When the feeding humidity is high, the stacking thickness of the biogas residue 9 is reduced, so that the hot air can pass through the biogas residue 9 more quickly and take away the water vapor, and the discharging humidity can be ensured to be within a reasonable range. Similarly, when the feeding humidity is low, the stacking thickness of the biogas residue 9 is increased. On the premise of ensuring reasonable discharging humidity, the quantity of biogas residue 9 processed per unit time is more, improving the efficiency. The feeder 1 spreads the biogas residue 9 with different thicknesses on the upper surface of the drying belt 7. After spreading, the bottom - layer biogas residue 9 can evenly contact the hot air, and the hot air will not flow downward only from the low - thickness biogas residue 9, resulting in incomplete drying of the deep - layer biogas residue 9 at the large - thickness position;

[0051] Regarding the negative - pressure fan 6, refer to Figure 1 , the negative - pressure fan 6 is fixed on the vertical side wall of the working section 3. The main body and the negative - pressure fan 6 are installed side by side, reducing the overall height of the equipment for convenient assembly. The negative - pressure fan 6 is connected to the return air area 34, and can also ensure that the air flow can pass through the biogas residue 9 from top to bottom and then be uniformly discharged. The negative - pressure fan 6 pumps the air in the contact area 32 into the return air area 34, and then continuously discharges the air in the return air area 34 from the main body. The hot air in the entire drying area operates under negative pressure, making the flow direction of the hot - air flow clearer, reducing the residence time of the hot air in the main body, and increasing the heat - transfer efficiency;

[0052] Regarding the air heat exchanger 5, refer to Figure 1, the air heat exchanger 5 has a thin-walled plate 52 filled with hot water. The thin-walled plate 52 is filled with hot water inside and is arranged directly above the working section 3. An outer shell 51 is sleeved outside the thin-walled plate 52. The outer shell 51 is communicated with the contact area 32, so that the outside air can fully contact and heat up with the thin-walled plate 52 under the guidance of the outer shell 51, and then blow downward to the position of the biogas residue 9. Among them, fins 53 are arranged on the outer wall of the thin-walled plate 52. The fins 53 are made of heat-conducting materials, which can increase the actual contact area between the air and the thin-walled plate 52, and thus achieve more efficient heat exchange, enabling the incoming air to rise to a higher temperature in a short time and efficiently drying the biogas residue 9 below. At the same time, the lower ends of the fins 53 are inclined away from the negative pressure fan 6, that is, the incoming air will blow backward and then flow forward across the drying zone 7 under the attraction of the front negative pressure fan 6. Compared with the vertical downward air inlet direction and the long-distance flow along the advancing direction of the drying zone 7, the flow direction of the hot air that is inclined backward and then turns forward can enable the hot air to cover the entire span of the drying zone 7 with a shorter flow path. That is to say, targeted hot air compensation can be carried out for the low-flow rate area, ensuring that the biogas residue 9 on the side of the drying zone 7 far from the negative pressure fan 6 can also be fully penetrated and dried by the hot air from top to bottom. It can also ensure that the hot air that absorbs water vapor flows out of the main body as soon as possible, preventing the water vapor in the main body from being saturated and condensing again in the low-flow rate area or low-temperature area, thereby ensuring that the entire drying zone 7 is within the range of rapidly replaced hot air coverage during drying.

[0053] In a further embodiment, to ensure that the drying zone 7 passes horizontally, refer to Figure 2 , the working section 3 includes a carrier frame 35. The carrier frame 35 has rod-shaped legs and a horizontally extending horizontal rod. The carrier frame 35 is fixed at the bottom surface of the working section 3. The carrier frame 35 is arranged below a part of the drying zone 7 located inside the working section 3. The horizontal rod of the carrier frame 35 supports a part of the drying zone 7 located inside the working section 3, ensuring the flatness of the drying zone 7 and preventing the middle of the drying zone 7 from sagging. This can ensure that the thickness of the feed is controllable and prevent the biogas residue 9 from gathering at the sagging position and resulting in an excessive stacking thickness that cannot be thoroughly dried. The carrier frame 35 is in sliding contact with the drying zone 7 without affecting the horizontal movement of the drying zone 7.

[0054] In a further embodiment, to adapt to biogas residues 9 with different humidities, refer to Figure 2, a lifting structure 11 is provided at the lower part of the feeder 1. Specifically, the lifting structure 11 includes a fixed frame, a sliding frame and a vertical screw. The fixed frame is fixedly connected to the top surface of the feeding section 2. The vertical screw is connected to the fixed frame through a nut. The sliding frame is rotatably connected to the vertical screw. The sliding frame is fixedly connected to the vertical side wall of the feeder 1. During adjustment, by rotating the vertical screw to jack up the sliding frame, the feeder 1 can be lifted. And at the overlapping position of the fixed frame and the sliding frame in the height direction, a locking bolt is provided. The locking bolt passes through the vertical sliding opening on the fixed frame and is connected to the sliding frame. After adjustment, the fixed frame and the sliding frame can be fixed by the locking bolt to ensure the position stability during use. And, please also refer to Figure 2 , a distributor 12 is provided at the outlet of the feeder 1. The distributor 12 has multiple outlets, which can disperse and feed the biogas residue 9 back and forth, facilitating the subsequent flattening work. A flattening member 13 is provided at the outlet of the distributor 12. The flattening member 13 is located downstream of the distributor 12. And the flattening member 13 is of a corrugated structure, which can push the biogas residue 9 to a position perpendicular to the advancing direction of the drying belt 7, quickly flatten the biogas residue 9. And there is a material passing space between the bottom surface of the flattening member 13 and the top surface of the drying belt 7, which can control the thickness of the biogas residue 9 after flattening. Specifically, the feeder 1 can also use a combination of a screw feeder and a spiral distributor (as shown in Figure 11 ). The feeder 1 is horizontally placed upstream of the drying belt 7, and the semi-dry biogas residue 9 is conveyed to the upstream of the drying belt 7 and dispersed and spread out to complete the feeding. Other structures that can achieve feeding and replenishing are not described in detail here. When the biogas residue 9 is relatively wet, the lifting structure 11 lowers the height of the feeder 1, reduces the material passing space between the bottom surface of the flattening member 13 and the top surface of the drying belt 7, reduces the thickness of the biogas residue 9, and disperses the feeding through the distributor 12 and levels it through the flattening member 13 to prevent incomplete drying caused by uneven stacking during drying. When the biogas residue 9 is relatively dry, the height of the feeder 1 can be increased to increase the amount of biogas residue 9 entering per unit time and improve the drying efficiency.

[0055] In a further embodiment, refer to Figure 2 、 Figure 3 and Figure 8, a driving roller 21 is built in the feeding section 2. The driving roller 21 is externally connected to a motor to drive the rotation of the drying belt 7. At the same time, a tensioning frame 211 is provided at the end of the driving roller 21 to straighten the drying belt 7 and prevent the lower part of the drying belt 7 from directly contacting the ground. Specifically, the tensioning frame 211 includes a sliding guide frame, a sliding bearing seat, and an adjusting screw. By rotating the adjusting screw, the sliding bearing seat can be pulled to horizontally slide within the sliding guide frame, and then the driving roller 21 can be moved left and right, thus realizing the tensioning action. A rotary roller 42 at the same height as the driving roller 21 is built in the discharging section 4. The rotary roller 42 is an idler. A first return turning roller 22 and a second return turning roller 44 are respectively provided below the driving roller 21 and the rotary roller 42 in the feeding section 2 and the discharging section 4. The drying belt 7 is wound between the driving roller 21, the rotary roller 42, the first return turning roller 22, and the second return turning roller 44 to form a belt structure, which can rotate to realize the continuous conveying work of the biogas residue 9. Moreover, the first return turning roller 22 and the second return turning roller 44 make the lower part of the drying belt 7 located at the lower part of the outside of the main body and contact the external air, which is convenient for maintenance from the outside of the equipment.

[0056] In a further embodiment, to improve the dehydration speed of the biogas residue 9 on the drying belt 7, referring to Figure 10 , a support roller 351 is provided on the upper part of the carrier frame 35. The support rollers 351 are arranged in the front-rear direction and extend horizontally. The support rollers 351 lift the drying belt 7. Moreover, the support rollers 351 are in rolling contact with the lower surface of a part of the drying belt 7 located inside the working section 3. The rolling support reduces wear. Support hairs 352 are installed on the circumferential side wall of the support roller 351 along the tangent direction. The support hairs 352 can be inserted into and pulled out of the mesh holes 71 from bottom to top when the support roller 351 rotates. By using the support hairs 352 to insert into the mesh holes 71, the biogas residue 9 above the drying belt 7 is lifted upward, making the biogas residue 9 fluffy and porous, more convenient for air to pass through, and also preventing the biogas residue 9 from being compacted on the drying belt 7 due to the unidirectional flow of hot air, resulting in caking. At the same time, the insertion and extraction of the support hairs 352 push the biogas residue 9 in the mesh holes 71 upward, penetrating the mesh holes 71 to avoid blockage, so that the hot air can pass through the stacked biogas residue 9 more smoothly and evenly. It should be noted that the support hairs 352 extend along the tangent direction of the circumferential side wall of the support roller 351, and the free ends of the support hairs 352 are arranged against the advancing direction of the drying belt 7, so that it is easier to penetrate into the mesh holes 71. Therefore, an external power source can be used to make all the support rollers 351 rotate counterclockwise. In this way, during the movement of the drying belt 7 from left to right, the support hairs 352 can penetrate the mesh holes 71 more easily and frequently, making the biogas residue 9 more fluffy and the downward flow of hot air more smooth;

[0057] Specifically, at least one support roller 351 (not shown in the figure) can also be arranged downstream of the drying belt 7. After feeding, the support roller 351 drives the support hairs 352 to rotate to brush the surface of the drying belt 7 to prevent material adhesion and ensure complete discharging.

[0058] In a further embodiment, the structure of the working section 3 is optimized. Referring to Figure 3 , the working section 3 includes a keel 36, which is made of galvanized steel self-supporting steel frame. The keel 36 is used to enhance the structural strength of the main body and facilitate the fixing of the skin 31. The skin 31 is divided into two layers, the inner and outer layers, which are respectively fixed on the inner and outer sides of the keel 36. The thickness of the keel 36 itself can form a sandwich layer in the skin 31 to fill with heat insulation material to delay heat dissipation and reduce heat loss. At the same time, a top frame 38 connected to the air heat exchanger 5 is provided at the top of the keel 36 for top air intake and heating by the air heat exchanger 5. A side frame 37 connected to the negative pressure fan 6 is provided on the vertical side wall of the keel 36. By using side exhaust instead of bottom exhaust, the negative pressure fan 6 can be arranged side by side with the main body without lifting the main body above the negative pressure fan 6, reducing the equipment height and facilitating the maintenance and installation of the main body. At the same time, guide rails 33 symmetrically arranged on both sides of the drying zone 7 are fixed inside the keel 36. The position of the guide rails 33 is higher than that of the side frame 37, which does not affect the separation of the internal contact area 32 and the return air area 34 of the main body by the drying zone 7. It should be emphasized that the guide rails 33 are in sliding contact with the vertical side walls of the drying zone 7. The guide rails 33 limit the drying zone 7 to prevent it from deviating forward and backward, and can also prevent the marsh slag 9 from falling from the front and rear sides of the drying zone 7. The upper part of the guide rails 33 is narrow and the lower part is wide, which plays a role in air diversion, so that the hot air blown on the inner wall of the rear side of the skin 31 can flow downward and be attracted forward by the negative pressure fan 6 in front, forming a flowing hot air from top to bottom and from back to front. Finally, the hot air passes through the marsh slag 9 and the drying zone 7 from top to bottom to complete the drying action.

[0059] In a further embodiment, to ensure that the deep marsh slag 9 can also fully contact the hot air flow, referring to Figure 5 and Figure 7, a ridger 39 is connected to the keel 36. The ridger 39 includes a horizontally arranged rotating shaft in the front-back direction and arms fixed on the circumferential side wall of the rotating shaft. The ridger 39 is arranged above a part of the inner side of the drying zone 7 located in the working section 3. By rotating the ridger 39, parallel ridges 91 are formed in the smooth biogas residue 9 along the advancing direction through the arms. The ridger 39 includes a first actuator 391 and a second actuator 392. Both the first actuator 391 and the second actuator 392 are rotating shafts with arms, but the arms of the two are arranged staggeredly in the front-back direction. And at least one first actuator 391 and one second actuator 392 are arranged on the working section 3. The first actuator 391 forms multiple parallel ridges 91 in the smooth biogas residue 9 along the advancing direction of the drying zone 7, making the upper surface of the biogas residue 9 uneven. And the hot air blows from top to bottom and from back to front, and can act on the windward surface of the ridges 91 almost vertically, greatly increasing the windward area of the biogas residue 9 and exposing the deep biogas residue 9 to the shallow layer, reducing the influence of the moisture in the upper biogas residue 9 on the drying progress of the lower biogas residue 9. At the same time, the arm of the second actuator 392 corresponds to the convex position of the biogas residue 9 where the ridges 91 have been formed, that is, the arm of the second actuator 392 is located at the gap between the adjacent arms of the first actuator 391. Ridges 91 are formed again at the convex position of the biogas residue 9 and the biogas residue 9 is piled up at the position of the old ridges 91, turning the deep biogas residue 9 that has not been turned out by the first actuator 391 to the shallow layer, performing alternating turning of the biogas residue 9, greatly improving the drying efficiency of the deep biogas residue 9. And multiple groups of the first actuator 391 and the second actuator 392 can be set to perform multiple reciprocating turnings, and the rapid drying of the biogas residue 9 is completed by using a shorter drying path.

[0060] In a further embodiment, to enable the hot air to fully contact the biogas residue 9 on the drying zone 7, referring to Figure 4 , the thin wall plate 52 adopts a serpentine coiled structure and has a certain length in the height direction. The thin wall plate 52 and the fins 53 are arranged in a grid-like staggered manner, dividing the intake air into multiple independent air guiding channels 54 through the thin wall plate 52 and the fins 53. The thin wall plate 52 is arranged in a structure where the bottom disperses and moves away from each other to the left and right sides, and is matched with the fins 53 with the bottom inclined backward. For such air guiding channels 54, after the intake air enters, it can be blown more dispersedly to the vertical inner wall at the rear side of the working section 3, fully covering the main internal space between the two air heat exchangers 5. After the hot air turns back forward, it evenly sweeps across the biogas residue 9 on a longer length of the drying zone 7 from back to front. At the same time, referring to Figure 4 , both ends of the thin wall plate 52 are externally connected to a heat source through a circulating water pipe 56. The circulating water pipe 56 keeps the thin wall plate 52 in a stable high-temperature state, preventing incomplete drying of the biogas residue 9 caused by insufficient heat. A protective net 55 is arranged above the thin wall plate 52 to filter the intake air and prevent solid debris from entering;

[0061] Preferably, the thin-walled plate 52 in the air heat exchanger 5 can also use a plate heat exchange structure, a shell-and-tube heat exchange structure or a finned-tube heat exchange structure. Based on the ability to provide a large heat exchange contact area, it can be replaced according to actual construction and will not be elaborated here.

[0062] In a further embodiment, to improve the continuous operation stability of the equipment, a drying belt cleaning mechanism is provided on the main body to prevent the mesh holes 71 of the drying belt 7 from being blocked by the biogas residue 9. Refer to Figure 6 - Figure 8 , the drying belt cleaning mechanism includes a spray pipe 8 and an air duct 61. The spray pipe 8 is installed directly above the drying belt 7. When drying is not in progress or during the drying interval, the spray pipe 8 can flush the drying belt 7. When in use for drying, the spray pipe 8 can also be controlled to open to play a fire prevention role, that is, if necessary, water mist spraying will be carried out above the biogas residue 9. Specifically, when the temperature inside the main body exceeds the limit value, the temperature sensor installed in the working section 3 will activate the valve of the spray pipe 8, and the drying belt 7 will be sprayed through the on-site water supply system. An additional manual valve can also be set to activate the spraying system at any time, and the fire prevention effect is good;

[0063] Please also refer to Figure 8 , the spray pipe 8 is connected to a flushing pipe 81 through a three-way reversing valve. The flushing pipe 81 is located downstream of the separation of the drying belt 7 and the biogas residue 9 in the discharge section 4. The air duct 61 is connected to the outlet of the negative pressure fan 6 and extends to the downstream of the separation of the drying belt 7 and the biogas residue 9 in the discharge section 4. During the drying process, the air duct 61 collects the high-temperature and high-humidity tail gas and guides it to the downstream of the drying belt 7. After the biogas residue 9 is separated from the drying belt 7, the drying belt 7 is purged and cleaned, and the tail gas is reasonably utilized. At the same time, before purging, the drying belt 7 can be cleaned by the high-pressure water flow of the flushing pipe 81, and then purged by the high-temperature air flow, so that the drying belt 7 can be thoroughly cleaned and quickly dried. A receiving hopper 43 is provided at the lower part of the discharge section 4 to collect the flushed biogas residue 9 for secondary recovery and reduce material waste.

[0064] In a further embodiment, to optimize the energy consumption of the equipment, refer to Figure 9 , a waste heat recovery mechanism is provided on the main body. The waste heat recovery mechanism includes an air collecting pipe 62. The air collecting pipe 62 is connected to the outlet of the negative pressure fan 6. A dehumidifier 63 is provided downstream of the air collecting pipe 62. During the drying process, after the negative pressure fan 6 draws out the high-temperature and high-humidity tail gas from the working section 3, it will be concentrated by the air collecting pipe 62 to the position of the dehumidifier 63. On the premise of ensuring that the waste heat is fully retained, the water vapor in the tail gas is separated. A distribution pipe 64 is installed at the outlet end of the dehumidifier 63. The distribution pipe 64 is communicated with the air inlet of the air heat exchanger 5, and then the dried tail gas is supplemented to the position of the air heat exchanger 5 through the distribution pipe 64 for secondary heating and circulating drying of the biogas residue 9;

[0065] Specifically, the dehumidifier 63 uses an electrostatic adsorption dehumidifier or a rotary adsorption dehumidifier. While removing water vapor in the tail gas, it will not reduce the temperature of the tail gas like a condensation dehumidifier, and retains the heat of the tail gas to the greatest extent to recover most of the heat to ensure efficient drying. The recycled tail gas is reheated to reduce tail gas emissions and heat loss.

[0066] In a further embodiment, referring to Figure 11 , an air selection and circulation mechanism is provided on the main body. The air selection and circulation mechanism includes a reflux pipe 65, and the reflux pipe 65 is connected between the outlet of the negative pressure fan 6 downstream and the air inlet of the air heat exchanger 5 upstream. Specifically, the negative pressure fan 6 downstream can be the most downstream negative pressure fan 6, and the air heat exchanger 5 upstream can be the most upstream air heat exchanger 5 and the subsequent two consecutive air heat exchangers 5. With this design, the tail gas with low humidity and high temperature can be directly led out for direct use. Moreover, these tail gases are led to the position of the upstream biogas residue 9 with high humidity. The trace water vapor in the recycled tail gas can be ignored compared to the water content of the just-dried biogas residue 9. Therefore, these tail gases can be directly used without treatment and will not affect the drying progress. Similarly, an exhaust pipe 67 is installed at the outlet of the negative pressure fan 6 located upstream. These high-humidity tail gases cannot be directly utilized and are directly led to the deodorizing tail gas machine for treatment and emission. A fresh air pipe 66 is installed at the air inlet of the air heat exchanger 5 located downstream to introduce external air into the main body to ensure sufficient total air volume for drying in the main body and ensure the drying efficiency. Through the setting of the air selection and circulation mechanism, while directly utilizing the waste heat of the untreated tail gas, the influence of water vapor in the tail gas on the drying progress is minimized as much as possible.

[0067] The above is only a preferred embodiment of the present invention and is not intended to limit the protection scope of the present invention.

Claims

1. A biogas residue drying and processing equipment, characterized in that: include: A main body, the main body comprising a feeding section (2), a working section (3) and a discharging section (4), the feeding section (2), the working section (3) and the discharging section (4) being arranged end to end, and the outer sides of the feeding section (2), the working section (3) and the discharging section (4) are provided with a skin (31); A drying belt (7), the drying belt (7) is arranged in a coiled manner through the main body, the drying belt (7) has mesh holes (71), and the drying belt (7) divides the internal space of the main body into a contact area (32) and a return air area (34) in upper and lower parts; A feeder (1), the feeder (1) being mounted on the feed section (2) in a liftable manner, the feeder (1) spreading the biogas residue (9) of different thicknesses on the upper surface of the drying belt (7); A negative pressure fan (6), the negative pressure fan (6) being fixed to a vertical side wall of the working section (3), the negative pressure fan (6) continuously extracting air from the contact area (32) and the return air area (34); An air heat exchanger (5), the air heat exchanger (5) comprising a thin-walled plate (52) filled with hot water, an outer shell (51) being sheathed on the outer side of the thin-walled plate (52), the outer shell (51) being in communication with the contact area (32), a fin (53) being provided on the outer wall of the thin-walled plate (52), the lower end of the fin (53) being inclined in a direction away from the negative pressure fan (6) so that the incoming air is sucked by the negative pressure fan (6) to cross the drying zone (7); The working section (3) comprises a bearing frame (35), the bearing frame (35) being fixed to the bottom surface of the working section (3), the bearing frame (35) being arranged below a portion of the drying belt (7) located inside the working section (3), the bearing frame (35) being in sliding contact with the drying belt (7); The working section (3) comprises a keel (36), a top frame (38) connected to the air heat exchanger (5) is provided on the top of the keel (36), a side frame (37) connected to the negative pressure fan (6) is provided on the vertical side wall of the keel (36), guide rails (33) symmetrically arranged on both sides of the drying belt (7) are fixed in the keel (36), the guide rails (33) are located higher than the side frames (37), and the guide rails (33) are in sliding contact with the vertical side walls of the drying belt (7); The keel (36) is connected to a ridging device (39), and the ridging device (39) is arranged above a portion of the drying belt (7) located inside the working section (3). The ridging device (39) comprises an actuator 1 (391) and an actuator 2 (392), and both the actuator 1 (391) and the actuator 2 (392) are rotating shafts with supporting arms, and the supporting arms of the actuator 2 (392) are located in the gap between the adjacent supporting arms of the actuator 1 (391).

2. The biogas residue drying and processing equipment according to claim 1, characterized in that: A support roller (351) is provided on the upper part of the support frame (35). The support roller (351) is in rolling contact with the lower surface of a portion of the drying belt (7) located inside the working section (3). Support hairs (352) are installed on the circumferential side wall of the support roller (351) along the tangential direction. The support hairs (352) can be inserted and pulled out of the mesh (71) from bottom to top when the support roller (351) rotates.

3. The biogas residue drying and processing equipment according to claim 1, characterized in that: A lifting structure (11) is provided at the lower part of the feeder (1), and the lifting structure (11) is fixedly connected to the top surface of the feeding section (2). A distributor (12) is provided at the outlet of the feeder (1), and the distributor (12) has a plurality of outlets. A flattening piece (13) is provided at the outlet of the distributor (12), and a material passing space is left between the bottom surface of the flattening piece (13) and the top surface of the drying belt (7).

4. The biogas residue drying and processing equipment according to claim 1, characterized in that: The thin-walled plates (52) adopt a serpentine coiling structure, the lower parts of the thin-walled plates (52) are spaced apart from each other along the extension direction of the drying belt (7), the thin-walled plates (52) and the fins (53) are arranged in a grid-like manner to form an air guide channel (54), both ends of the thin-walled plates (52) are connected to an external heat source through a circulating water pipe (56), and a protective net (55) is provided above the thin-walled plates (52).

5. The biogas residue drying and processing equipment according to claim 1, characterized in that: The main body is provided with a drying belt cleaning mechanism, the drying belt cleaning mechanism comprising a spray pipe (8) and an air guide pipe (61), the spray pipe (8) being mounted directly above the drying belt (7), the spray pipe (8) being connected to a flushing pipe (81) via a three-way reversing valve, the flushing pipe (81) being located downstream of the drying belt (7) and the biogas residue (9) being separated in the discharge section (4), and the air guide pipe (61) being connected to the outlet of the negative pressure fan (6) and extending to the downstream of the drying belt (7) and the biogas residue (9) being separated in the discharge section (4).

6. The biogas residue drying and processing equipment according to claim 1, characterized in that: A waste heat recovery mechanism is provided on the main body, the waste heat recovery mechanism comprising an air collecting pipe (62), the air collecting pipe (62) being connected to the outlet of the negative pressure fan (6), a dehumidifier (63) being provided downstream of the air collecting pipe (62), an air distribution pipe (64) being installed at the outlet end of the dehumidifier (63), and the air distribution pipe (64) being communicated with the air inlet of the air heat exchanger (5).

7. The biogas residue drying and processing equipment according to claim 1, characterized in that: The main body is provided with an air selection circulation mechanism, the air selection circulation mechanism comprising a return pipe (65), the return pipe (65) being connected between the outlet of the downstream negative pressure fan (6) and the air inlet of the upstream air heat exchanger (5), an exhaust pipe (67) being installed at the outlet of the upstream negative pressure fan (6), and a fresh air pipe (66) being installed at the air inlet of the downstream air heat exchanger (5).

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