A sludge dehydration and drying device and method

Abstract

A sludge dehydration and drying device and method, belonging to the technical field of sludge treatment, wherein the device comprises a heating pre-dehydration chamber and upper and lower filter cloths and a high-pressure dehydration assembly, the upper and lower filter cloths pass through the sludge conveying channel formed by the heating pre-dehydration chamber, the upper and lower filter cloths are fed and collected along the channel, the heating pre-dehydration chamber is provided with a feed port for inputting sludge, the outer sides of the upper and lower filter cloths are provided with sliding rollers, the heating pre-dehydration chamber is provided with a flue gas inlet to heat and condition the sludge in the filter cloth interlayer online to achieve heating pre-dehydration, one end of the heating pre-dehydration chamber is provided with a high-pressure dehydration assembly, the high-pressure dehydration assembly comprises a high-pressure dehydration tank and a matching hydraulic cylinder, the high-pressure dehydration tank is provided with a circulating cloth mechanism to reciprocately fold the interlayer filter cloth in the high-pressure dehydration tank, and the hydraulic cylinder presses the multi-layer filter cloth for high-pressure dehydration. The present invention realizes deep drying and dehydration, and finally obtains a sludge moisture content of <10%, and has the advantages of high dehydration efficiency, low operating cost, strong practicality, etc.

Description

Technical Field

[0001] The invention discloses a sludge dehydration and drying device and method, which belong to the technical field of sludge treatment according to the International Patent Classification (IPC). Background Art

[0002] For the traditional ordinary belt filter press dehydrator, due to the low squeezing force between the upper and lower power tension filter belts, deep dehydration cannot be achieved. The moisture content of the sludge after dehydration is generally around 80%. The high moisture content of the sludge not only leads to automobile transportation costs, but also increases the subsequent disposal costs of the sludge. Although the traditional belt dryer also has a heating device, in order to achieve the drying and dehydration goals, the drying time is getting longer and longer, the drying efficiency is low, and when the flue gas waste heat and waste energy are used, the drying device is bulky and the investment and operation costs are high; moreover, due to the process between the conveyor belt mesh aperture size and the ventilation performance and the material carrying performance is difficult to control, the conveyor belt aperture that is too small is difficult to ensure good ventilation performance, and the drying effect is uneven. On the other hand, the existing high-pressure dehydrator directly presses the sludge after conditioning it with inorganic additives such as lime, which has high filter pressing costs and unstable operation.

[0003] Chinese document CN107814472A discloses a sludge drying treatment method and device, which belongs to the field of solid waste treatment, including a heat source and a sludge drying treatment machine, wherein the sludge drying treatment machine includes a roller press, a toothed knife forming machine and a stirring dryer from top to bottom; the sludge that has undergone simple air drying and sedimentation treatment is transported to the roller press by a feeder to be rolled into a thin mud cake, the toothed knife forming machine cuts the thin mud cake into strips, and the sludge particles enter the stirring dryer and are heated and turned over multiple times to reduce the moisture content of the sludge particles to a specified range, and are transported to a specified location through a discharging machine to complete the sludge drying treatment. Chinese document CN109516668A discloses a novel low-temperature hot air sludge drying machine, comprising a feed uniform distribution system, a sludge drying chamber, a sludge transmission self-cleaning system, a hot air circulation uniform distribution system and a discharge collection system; the feed uniform distribution system comprises a fixed frame, a feed conveyor belt arranged on the fixed frame, a loader and a roller, the loader and the roller covered by the feed conveyor belt are installed on the fixed frame, and the top of the feed conveyor belt extends into the sludge drying chamber; the sludge transmission self-cleaning system comprises a drying conveyor mesh belt, an anti-adhesion scraper and a material rake, and a material rake and an anti-adhesion scraper are respectively installed above and below the drying conveyor mesh belt; the hot air circulation uniform distribution system comprises a dust removal device, a dehumidification device, and an air heating device in sequence. Chinese document CN105115271A discloses a belt dryer, which includes a dryer shell, a dryer cavity, a transmission device and a heating and drying system. The dryer shell is provided with a feeding hopper, and the dryer cavity is provided with an air intake fan port, a circulation fan port, an exhaust fan port and a moisture removal fan port. The belt dryer is suitable for drying Chinese medicinal materials and solves the defects of traditional belt dryers such as easy clogging when feeding and uneven material distribution.

[0004] Comprehensive analysis of the above patent documents shows that all of them use belt dryers to achieve sludge drying in one step, which leads to high equipment investment and operating costs, and it is difficult to solve the problems of sludge dehydration, fine particles, high viscosity and high energy consumption, etc., and the dehydration efficiency is low and the environmental impact is large. Since sludge dehydration and reduction is the primary problem that should be solved for sludge resource utilization and harmlessness, the development of new sludge dehydration and drying devices and methods has important application value. Summary of the invention

[0005] In view of the deficiencies in the prior art, the present invention provides a sludge dehydration and drying device, which combines belt heating pre-dehydration with sludge thin layer deep drying and has good application value.

[0006] To achieve the above object, the present invention is achieved through the following technical solutions:

[0007] A sludge dehydration and drying device comprises a heating pre-dehydration chamber, upper and lower filter cloths and a high-pressure dehydration component. The upper and lower filter cloths pass through a sludge conveying channel formed by the heating pre-dehydration chamber, and the upper and lower filter cloths are fed and collected along the channel. The heating pre-dehydration chamber is provided with a feed port for inputting sludge, and the outer sides of the upper and lower filter cloths are provided with sliding rollers. The heating pre-dehydration chamber is provided with a flue gas inlet to heat and condition the sludge in the filter cloth interlayer online to achieve heating pre-dehydration. One end of the heating pre-dehydration chamber is provided with a high-pressure dehydration component, and the high-pressure dehydration component comprises a high-pressure dehydration trough and a matching hydraulic cylinder. The high-pressure dehydration trough is provided with a circulating cloth mechanism to reciprocally fold the interlayer filter cloth in the high-pressure dehydration trough, and the hydraulic cylinder presses multiple layers of filter cloth for high-pressure dehydration.

[0008] Furthermore, an upper filter cloth drum and a lower filter cloth drum are provided at one end of the heated pre-dehydration chamber, and are used in conjunction with the upper and lower filter cloths respectively. The upper filter cloth drum and the lower filter cloth drum can work forward for feeding and filter pressing dehydration, and can also work reversely for discharging. A dehydrated sludge storage bin is provided at the outlet where the upper filter cloth drum and the lower filter cloth drum cooperate. An upper filter cloth discharging roller and a lower filter cloth discharging roller are provided at one end of the heated pre-dehydration chamber. The upper filter cloth discharging roller and the lower filter cloth discharging roller drag out the double-layer filter cloth by friction.

[0009] Furthermore, a 40-60 mm insulation layer is provided in the heating pre-dehydration chamber, the bottom of the heating pre-dehydration chamber is an oblique flow plate, the lowest point of the oblique flow plate is a water collecting trough, and the water collecting trough is drained outward through a drain pipe. The circulating cloth mechanism includes a repeated sliding roller to realize the stacking distribution of double-layer filter cloth in the high-pressure dehydration trough, preparing for subsequent high-pressure dehydration.

[0010] Furthermore, the hydraulic cylinder is connected to the hydraulic hammer through a hydraulic telescopic rod. The hydraulic hammer is facing the high-pressure dehydration tank. A drainage interlayer is formed between the filter cloth accommodating cavity and the inner wall of the high-pressure dehydration tank. The four walls and the bottom of the filter cloth accommodating cavity have mesh-shaped drainage holes that are evenly distributed. Water squeezed out of the multiple layers of filter cloth flows into the drainage interlayer, and the drainage interlayer is drained outward through a drainage pipe.

[0011] Furthermore, an upper filter cloth scraper and a lower filter cloth scraper are correspondingly provided on one side of the upper filter cloth reel and the lower filter cloth reel. One end of each scraper is fixed by a hinge, and the other end is preloaded by a spring to make the scraper close to the outer surface of the filter cloth. The upper filter cloth scraper and the lower filter cloth scraper are rectangular iron plates or angle irons.

[0012] Furthermore, upper and lower sliding rollers are provided on the outer sides of the upper and lower filter cloths respectively. The upper sliding rollers are tilted and evenly distributed, and the lower sliding rollers are arranged horizontally, corresponding to each other. The included angle between the center lines of the two sliding rollers is less than 5 degrees. The added material is evenly spread on the filter cloth or filter belt, and the material thickness is less than 3mm before entering the high-pressure dewatering tank.

[0013] Furthermore, the feed port of the heating pre-dehydration chamber is connected to the stirring tank through a mud pump and a conveying pipe. The feed port of the heating pre-dehydration chamber is located at the vertical axial center of the lower filter cloth. The flue gas inlet is located at the lower part of the heating pre-dehydration chamber. A flue gas outlet is provided at the upper part of the heating pre-dehydration chamber to realize the flue gas entering from the bottom and exiting from the top, and to make full use of the waste heat. The flue gas preferably uses waste flue gas generated by sludge pyrolysis or incineration, and other low-quality waste heat steam may also be used.

[0014] The present invention also provides a sludge dehydration and drying method, comprising the following steps:

[0015] a) The sludge and the conditioning agent are mixed in a stirring tank, and the mixed material after stirring is transported to the feed inlet of the sludge dehydration and drying device;

[0016] b) The sludge flowing out of the feed port flows to the center line of the lower filter cloth, and is squeezed by two rows of multi-layer sliding rollers to be laid flat between the upper and lower filter cloths;

[0017] c) In the heating pre-dehydration chamber, a flue gas inlet is provided at the bottom; hot flue gas enters from the flue gas inlet and is discharged from the flue gas outlet, heating and pre-dehydrating the filter cloth and the sludge sandwiched in the filter cloth, and at the same time, heating conditioning is achieved, and the dripping water flows from the inclined flow plate to the water collecting tank and is discharged through the drain pipe; the evaporated water is discharged together with the flue gas;

[0018] d) The sludge is pre-dehydrated and heated online at the same time; then, the upper and lower filter cloths are gradually pulled out by the upper filter cloth discharge roller and the lower filter cloth discharge roller by friction; the circulating cloth mechanism folds the sandwich filter cloth in the high-pressure dewatering tank;

[0019] e) After the high-pressure dewatering tank is filled with filter cloth, the feeding is stopped, and the hydraulic cylinder drives the hydraulic telescopic rod to push the hydraulic hammer to perform high-pressure dewatering on the multiple layers of filter cloth in the high-pressure dewatering tank; the four walls and the bottom of the high-pressure dewatering tank are all mesh outlets, so that the water is squeezed into the drainage interlayer; the filtered water in the drainage interlayer is discharged through the drainage pipe;

[0020] f) After the sludge is dehydrated under high pressure in the two layers of filter cloth, the hydraulic cylinder drives the hydraulic telescopic rod to push the hydraulic hammer out of the high pressure dehydration tank; the upper filter cloth reel and the lower filter cloth reel roll in opposite directions, gradually dragging the double-layer filter cloth in the high pressure dehydration tank back to the heating pre-dehydration chamber; the two layers of filter cloth after high pressure and the sludge flakes in the middle are flattened between the upper and lower rows of multi-layer sliding rollers, and are further heated and dried by the flue gas waste heat before discharging;

[0021] g) At the same time, due to the reverse rolling of the upper filter cloth drum and the lower filter cloth drum, the sludge flakes are released, and the sludge is scraped into the dewatered sludge storage bin by the joint action of the upper filter cloth scraper and the lower filter cloth scraper, completing a sludge dewatering cycle;

[0022] h) After the discharge of the sludge high-pressure dehydration sheet is completed, the sludge dehydration begins to enter the next cycle, the upper filter cloth drum and the lower filter cloth drum are rolled forward; at the same time, the upper filter cloth discharge roller and the lower filter cloth discharge roller are dragged forward; the mud pump again transports the sludge from the conveying pipe to the feed port in the sludge dehydration and drying device, and the next dehydration working cycle begins at the center line position of the lower filter cloth drum.

[0023] Furthermore, the conditioning agent is at least one of sludge pyrolysis or incineration residues, and the conditioning agent addition ratio is 5%-10% of the weight of the wet sludge; the feed sludge stays in the heated pre-dehydration chamber for 10 to 15 minutes; the high-pressure dehydration pressure is >3MPa, and the filtration time is >5min.

[0024] Furthermore, the temperature of the flue gas at the inlet of the pre-dehydration chamber is heated to 100-180°C, preferably the waste flue gas generated by the sludge pyrolysis or incineration process; the dehydrated sludge flakes stay in the heating chamber for 5-10 minutes before being discharged.

[0025] The sludge in the present invention refers to municipal sludge or industrial sludge; the sludge has fine particles, high viscosity, and a water content of more than 80% by weight. The present invention has the following beneficial effects:

[0026] 1. Basic Principle of the Invention After the sludge is mixed with the conditioning agent, the sludge is transported by a double-layer filter cloth. On the one hand, the upper and lower rows of sliding rollers are used to spread the sludge, and on the other hand, the filter cloth and the sludge in the filter cloth interlayer are heated by the waste heat of the flue gas to achieve heating pre-dehydration. The heating pre-dehydration process heats and conditions the sludge at the same time, and the sludge is further entrained by the double-layer filter cloth to the high-pressure dehydration tank to achieve high-pressure dehydration. The sludge flakes sandwiched in the double-layer filter cloth obtained after high-pressure dehydration are further sent back to the heating chamber by the double-layer filter cloth to achieve deep drying and dehydration, and finally the sludge moisture content is <10%.

[0027] 2. The method of the present invention has multiple functions such as belt heating pre-dehydration, heating conditioning coupled with multi-layer filter cloth high-pressure dehydration, and sludge thin layer deep drying. It has the advantages of relatively simple process, high dehydration efficiency, small footprint, low operating cost, strong practicality, etc., and has good application value.

[0028] 3. In the conditioning process, the present invention uses sludge incineration residue or sludge pyrolysis residue as a conditioning agent to achieve waste treatment with waste; the conditioning agent has porous properties and good water absorption. While spreading the sludge, it changes the sludge gel structure, so that the water trapped in the sludge flocs is fully released, and the migration and precipitation of water in the sludge is achieved through the skeleton effect and water absorption effect of the conditioning agent, laying the foundation for heating pre-dehydration and subsequent high-pressure dehydration. Since the process of heating and pre-dehydrating the sludge thin layer by fully utilizing the waste heat of flue gas is also a heating conditioning process, the conditioned sludge has been heated and broken before entering the high-pressure dehydration device, and the dehydration efficiency is greatly improved when entering the high-pressure dehydration device for filter press dehydration.

[0029] 4. In addition, when the sludge flakes after high-pressure dehydration of the present invention return to the heating chamber, the waste heat flue gas reheats them to further remove moisture, so that the sludge is finally deeply dehydrated. The solution provided by the present invention fully solves the technical problems of high energy consumption and complex treatment process of sludge dehydration and drying, and has significant energy-saving and environmental protection benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic diagram of an embodiment of the present invention.

[0031] Figure 2 It is a diagram of a feeding device when a sludge dehydration and drying device is implemented in the present invention. DETAILED DESCRIPTION

[0032] The present invention will be further described below in conjunction with the accompanying drawings:

[0033] Example: See Figure 1 and Figure 2 A sludge dehydration and drying device comprises a heating pre-dehydration chamber 8 and upper and lower filter cloths 4, 5 and a high-pressure dehydration component. The upper and lower filter cloths pass through a sludge conveying channel formed by the heating pre-dehydration chamber 8. The upper and lower filter cloths 4, 5 are fed and collected along the channel. The heating pre-dehydration chamber 8 is provided with a feed port 3 for inputting sludge. The outer sides of the upper and lower filter cloths 4, 5 are provided with a sliding roller 6. The heating pre-dehydration chamber is provided with a flue gas inlet 11 to heat and condition the sludge in the filter cloth interlayer online to achieve heating pre-dehydration. A high-pressure dehydration component is provided at one end of the heating pre-dehydration chamber 8. The high-pressure dehydration component comprises a high-pressure dehydration tank 18 and a matching hydraulic cylinder 15. A circulating cloth mechanism 14 is provided on the high-pressure dehydration tank 18 to fold the interlayer filter cloth back and forth in the high-pressure dehydration tank 18. The hydraulic cylinder presses multiple layers of filter cloth for high-pressure dehydration.

[0034] The sludge dehydration and drying device of the present invention is also called a sludge online conditioning high-pressure dehydration and drying device. Figure 1 and Figure 2 As shown, it specifically includes: an upper filter cloth drum 1, a lower filter cloth drum 2, a feed inlet 3, an upper filter cloth 4, a lower filter cloth 5, a slide roller 6, an oblique flow plate 7, a heating pre-dehydration chamber 8, a water collecting trough 9, a flue gas inlet 10, a flue gas outlet 11, an upper filter cloth discharging roller 12, a lower filter cloth discharging roller 13, a circulating cloth mechanism 14, a hydraulic cylinder 15, a hydraulic telescopic rod 16, a hydraulic hammer 17, a high-pressure dehydration trough 18, a drainage interlayer 19, a drainage pipe 20, an upper filter cloth scraper 21, a lower filter cloth scraper 22, a dehydrated sludge storage bin 23, a stirring tank 24, a stirring motor 25, a mud pump 26, and a conveying pipe 27.

[0035] See also Figure 1In the present invention, an upper filter cloth reel 1 and a lower filter cloth reel 2 are provided at one end of the heating pre-dehydration chamber 8 to cooperate with the upper and lower filter cloths 4 and 5 respectively. The upper filter cloth reel 1 and the lower filter cloth reel 2 can work forward for feeding and filter pressing dehydration, and can also work reversely for discharging. A dehydrated sludge storage bin 23 is provided at the outlet where the upper filter cloth reel 1 and the lower filter cloth reel 2 cooperate. An upper filter cloth discharging drag roller 12 and a lower filter cloth discharging drag roller 13 are provided at one end of the heating pre-dehydration chamber 8. The upper filter cloth discharging drag roller 12 and the lower filter cloth discharging drag roller 13 drag the double-layer filter cloth out by friction. A 40-60 mm insulation layer is provided in the heating pre-dehydration chamber 8. The bottom of the heating pre-dehydration chamber 8 is an inclined flow plate 7. The lowest point of the inclined flow plate 7 is a water collecting tank 9. The water collecting tank 9 drains water outward through a drainage pipe 20. The hydraulic cylinder 15 is connected to the hydraulic hammer 17 through the hydraulic telescopic rod 16. The hydraulic hammer 17 is facing the high-pressure dewatering tank 18. A drainage interlayer 19 is formed between the filter cloth cavity and the inner wall of the high-pressure dewatering tank 18. The four walls and the bottom of the filter cloth cavity have mesh-like evenly distributed drainage holes, and the water squeezed out of the multi-layer filter cloth flows into the drainage interlayer, and the drainage interlayer is drained outward through the drainage pipe 20. An upper filter cloth scraper 21 and a lower filter cloth scraper 22 are correspondingly arranged on one side of the upper filter cloth reel 1 and the lower filter cloth reel 2. One end of each scraper is fixed by a hinge, and the other end is preloaded by a spring to make the scraper close to the outer surface of the filter cloth. The upper filter cloth scraper 21 and the lower filter cloth scraper 22 are rectangular iron plates or angle irons. The outer sides of the upper and lower filter cloths 4 and 5 are provided with upper and lower sliding rollers respectively. The upper sliding rollers are tilted and evenly distributed, and the lower sliding rollers are arranged horizontally, one by one. The angle between the center lines of the two sliding rollers is less than 5 degrees. The added materials are evenly spread on the filter cloth or filter belt, and the material thickness before entering the high-pressure dehydration tank is less than 3mm. The feed port of the heating pre-dehydration chamber 8 is connected to the stirring tank 24 through a mud pump 26 and a conveying pipe 27. The feed port of the heating pre-dehydration chamber 8 is located at the vertical axial center of the lower filter cloth 5. The flue gas inlet 10 is located at the bottom of the heating pre-dehydration chamber 8. The upper part of the heating pre-dehydration chamber 8 is provided with a flue gas outlet 11, so that the flue gas enters from the bottom and exits from the top, and the waste heat is fully utilized. The flue gas is preferably waste flue gas generated by sludge pyrolysis or incineration, and other low-quality waste heat steam can also be used.

[0036] The present invention provides a sludge dehydration and drying method, wherein the dehydration process comprises the following steps:

[0037] a) The sludge and the conditioning agent are mixed in a stirring tank 24, and the stirring tank 24 is equipped with a stirring device 25; the stirred mixture is transported by a slurry pump 26 and transported by a conveying pipe 27 to a feed port 3 in a sludge dehydration and drying device;

[0038] b) The sludge flowing out of the feed port 3 flows to the center line of the lower filter cloth drum 2, and is squeezed by two rows of multi-layer sliding rollers 6 to be laid flat between the upper filter cloth 4 and the lower filter cloth 5;

[0039] c) A hot flue gas inlet 10 is provided at the bottom of the heating pre-dehydration chamber 8; the hot flue gas enters from the flue gas inlet 10 and is discharged from the flue gas outlet 11, heating and pre-dehydrating the filter cloth in the heating pre-dehydration chamber 8 and the sludge sandwiched in the filter cloth, and at the same time, heating conditioning is achieved. The dripping water flows from the inclined flow plate 7 to the water collecting tank 9 and is discharged through the drain pipe 20; the evaporated water is discharged together with the flue gas;

[0040] d) The sludge is pre-dehydrated and heated online at the same time; then, the upper and lower filter cloths are gradually pulled out by the upper filter cloth discharge drag roller 12 and the lower filter cloth discharge drag roller 13 by friction; the sandwich filter cloth circulation cloth is folded in the high-pressure dewatering tank 18 by the circulation cloth mechanism 14;

[0041] e) After the high-pressure dewatering tank 18 is filled with filter cloth, the feeding is stopped. The upper filter cloth drum 1 and the lower filter cloth drum 2 stop; the upper filter cloth discharge roller 12 and the lower filter cloth discharge roller 13 stop; the circulating cloth mechanism 14 stops; the sludge pump 26 stops conveying and conveys the sludge through the conveying pipe 27 to the feed port 3 in the sludge dewatering and drying device;

[0042] f) The hydraulic cylinder 15 drives the hydraulic telescopic rod 16 to push the hydraulic hammer 17 to perform high-pressure dehydration on the multi-layer filter cloth in the high-pressure dehydration tank 18; the four walls and the bottom of the filter cloth cavity in the high-pressure dehydration tank 18 are provided with mesh-shaped drainage holes evenly distributed, so that water is squeezed into the drainage interlayer 19; the filtered water in the drainage interlayer 19 is discharged through the drainage pipe 20;

[0043] g) After the sludge is dehydrated under high pressure in the two layers of filter cloth, the hydraulic cylinder 15 drives the hydraulic telescopic rod 16 to push the hydraulic hammer 17 to leave the high pressure dehydration tank 18; the upper filter cloth reel 1 and the lower filter cloth reel 2 roll in opposite directions to gradually drag the double-layer filter cloth in the high pressure dehydration tank 18 back to the heating pre-dehydration chamber 8; the two layers of filter cloth after high pressure and the sludge flakes in the middle are spread flat between the upper and lower rows of multi-layer sliding rollers 6, and are further heated and dried by the flue gas waste heat before discharging;

[0044] h) At the same time, as the upper filter cloth drum 1 and the lower filter cloth drum 2 roll in opposite directions, the sludge flakes are released, and the sludge is scraped into the dewatered sludge storage bin 23 by the joint action of the upper filter cloth scraper 21 and the lower filter cloth scraper 22, completing one sludge dewatering cycle;

[0045] i) After the sludge high-pressure dewatering sheet is discharged, the sludge dewatering starts to enter the next cycle, and the upper filter cloth drum 1 and the lower filter cloth drum 2 are rolled forward; at the same time, the upper filter cloth discharge drag roller 12 and the lower filter cloth discharge drag roller 13 are dragged forward; the mud pump 26 again transports the sludge through the conveying pipe 27 to the feed port 3 in the sludge dewatering and drying device, and the next dewatering working cycle starts at the center line position of the lower filter cloth drum 2.

[0046] In the above steps, the conditioning agent is at least one of the residues from sludge pyrolysis or incineration, and the proportion of the conditioning agent added is 5%-10% of the weight of the wet sludge; the feed sludge stays in the heating pre-dehydration chamber for 10-15 minutes; the high-pressure dehydration pressure is >3MPa, and the filter pressing time is >5min. The flue gas temperature at the inlet of the heating pre-dehydration chamber is 100-180°C, and the waste flue gas generated by the sludge pyrolysis or incineration process is preferred; the dehydrated sludge flakes stay in the heating chamber for 5-10 minutes before being discharged.

[0047] The present invention provides a sludge dehydration and drying device, wherein the feeding device is as follows: Figure 2 , among which, 24. agitating tank, 25. agitating motor, 26. mud pump, 27. conveying pipe.

[0048] The oblique flow plate 7, the heating pre-dehydration chamber 8 and the water collecting tank 9 in the present invention are all made of ordinary carbon steel; the upper filter cloth discharging drag roller 12 and the lower filter cloth discharging drag roller 13 drag the double-layer filter cloth out by friction; preferably, a circular outer roller or a toothed outer roller; the circulating cloth mechanism 14 is a cyclic and repeated sliding roller to realize the stacking distribution of the double-layer filter cloth in the high-pressure dehydration tank 18, in preparation for the subsequent high-pressure dehydration; the hydraulic cylinder 15, the hydraulic telescopic rod 16 and the hydraulic hammer 17 are conventional hydraulic devices; the upper filter cloth scraper 21 and the lower filter cloth scraper 22 are made of ordinary carbon steel, and the stirring tank 24 is made of ordinary carbon steel; the matching stirring device 25 is a common blade stirring device; the mud pump 26 is a conventional mud pump; and the conveying pipe 27 is a common steel pipe. The heating pre-dehydration chamber can also be called a heating chamber.

[0049] The device of the present invention simultaneously has multiple functions such as belt pre-dehydration, heating conditioning, high-pressure multi-layer filter cloth dehydration, and sludge thin layer deep dehydration. It can better solve the problems of fine sludge particles, large viscosity, and difficult dehydration, greatly saves processing costs, has high dehydration efficiency, strong practicality, and has good application value.

[0050] The above records are only embodiments of the present invention. Any modification or change made by a person familiar with the present technology using the present invention shall fall within the patent scope claimed by the present invention and shall not be limited to those disclosed in the embodiments.

Claims

1. A sludge dehydration and drying device, characterized in that: It includes a heating pre-dehydration chamber and upper and lower filter cloths and a high-pressure dehydration assembly. The upper and lower filter cloths pass through the heating pre-dehydration chamber to form a sludge conveying channel. The upper and lower filter cloths are fed and collected along the channel. The heating pre-dehydration chamber is provided with a feed port for inputting sludge. The outer sides of the upper and lower filter cloths are provided with sliding rollers. The heating pre-dehydration chamber is provided with a flue gas inlet to heat and condition the sludge in the filter cloth interlayer online to achieve heating pre-dehydration. Hot flue gas enters from the flue gas inlet. The hot flue gas is waste flue gas generated during sludge pyrolysis or incineration. A high-pressure dehydration assembly is provided at one end of the heating pre-dehydration chamber. The high-pressure dehydration assembly includes a high-pressure dehydration tank and a matching hydraulic cylinder. A circulating cloth mechanism is provided on the high-pressure dehydration tank to fold the sandwich filter cloth back and forth in the high-pressure dehydration tank. The hydraulic cylinder presses the multiple layers of filter cloth for high-pressure dehydration. The two layers of filter cloth and the middle sandwich sludge flakes after high-pressure dehydration are flattened between the upper and lower rows of sliding rollers, and are further heated and dried by the waste heat of hot flue gas before discharging. The sludge and the conditioning agent are mixed in a stirring tank, and the mixed material after stirring is transported to the feed port of the heating pre-dehydration chamber; the conditioning agent is at least one of the sludge pyrolysis or incineration residues, and the addition ratio of the conditioning agent is 5%-10% of the weight of the wet sludge; An upper filter cloth drum and a lower filter cloth drum are provided at one end of the heating pre-dehydration chamber, which are used in conjunction with the upper and lower filter cloths respectively. The upper filter cloth drum and the lower filter cloth drum can work forward for feeding and filter pressing and dehydration, and can also work reversely for discharging.

2. A sludge dehydration and drying device according to claim 1, characterized in that: A dewatered sludge storage bin is provided at the outlet where the upper filter cloth drum and the lower filter cloth drum cooperate, and an upper filter cloth discharging drag roller and a lower filter cloth discharging drag roller are provided at one end of the heating pre-dehydration chamber. The upper filter cloth discharging drag roller and the lower filter cloth discharging drag roller drag the double-layer filter cloth out by friction.

3. The sludge dehydration and drying device according to claim 1, characterized in that: A 40~60mm insulation layer is provided in the heating pre-dehydration chamber. The bottom of the heating pre-dehydration chamber is an inclined flow plate. The lowest point of the inclined flow plate is a water collecting trough. The water collecting trough is drained outward through a drain pipe. The circulating cloth mechanism includes a repeated sliding roller to realize the stacking distribution of double-layer filter cloth in the high-pressure dehydration trough, preparing for subsequent high-pressure dehydration.

4. The sludge dehydration and drying device according to claim 1, characterized in that: The hydraulic cylinder is connected to the hydraulic hammer through a hydraulic telescopic rod. The hydraulic hammer is facing the high-pressure dehydration tank. A drainage interlayer is formed between the filter cloth accommodating cavity and the inner wall of the high-pressure dehydration tank. The four walls and the bottom of the filter cloth accommodating cavity have mesh-shaped drainage holes evenly distributed. The water squeezed out of the multi-layer filter cloth flows into the drainage interlayer, and the drainage interlayer is drained outward through the drainage pipe.

5. The sludge dehydration and drying device according to claim 2, characterized in that: An upper filter cloth scraper and a lower filter cloth scraper are provided on one side of the upper filter cloth reel and the lower filter cloth reel respectively. One end of each scraper is fixed by a hinge, and the other end is preloaded with a spring to make the scraper close to the outer surface of the filter cloth. The upper filter cloth scraper and the lower filter cloth scraper are rectangular iron plates or angle irons.

6. The sludge dehydration and drying device according to claim 2, characterized in that: The outer sides of the upper and lower filter cloths are provided with upper and lower sliding rollers respectively. The upper sliding rollers are tilted and evenly distributed, and the lower sliding rollers are arranged horizontally, one by one. The included angle between the center lines of the two sliding rollers is less than 5 degrees. The added materials are evenly spread on the filter cloth or filter belt, and the thickness of the materials before entering the high-pressure dewatering tank is less than 3mm.

7. A sludge dehydration and drying method, the sludge dehydration and drying device used includes a heating pre-dehydration chamber and upper and lower filter cloths and a high-pressure dehydration component; the upper and lower filter cloths pass through the heating pre-dehydration chamber to form a sludge conveying channel; the upper and lower filter cloths are fed and collected along the channel, the heating pre-dehydration chamber is provided with a feed inlet for inputting sludge, the outer sides of the upper and lower filter cloths are provided with sliding rollers, the heating pre-dehydration chamber is provided with a flue gas inlet to heat and online condition the sludge in the filter cloth sandwich to achieve heating pre-dehydration, the hot flue gas enters from the flue gas inlet, and the hot flue gas selects the waste flue gas generated by the pyrolysis or incineration process of the sludge; a high-pressure dehydration component is provided at one end of the heating pre-dehydration chamber, the high-pressure dehydration component includes a high-pressure dehydration tank and a matching hydraulic cylinder, and a circulating cloth mechanism is provided on the high-pressure dehydration tank to heat the sandwich The filter cloth is folded back and forth in the high-pressure dehydration tank, and the hydraulic cylinder presses multiple layers of filter cloth for high-pressure dehydration. The two layers of filter cloth after high-pressure dehydration and the middle layer of sludge flakes are laid flat between the upper and lower rows of sliding rollers, and are further heated and dried by the waste heat of hot flue gas before discharging; the sludge and the conditioner are mixed with the conditioner in the stirring tank, and the mixed material after stirring is transported to the feed port of the heated pre-dehydration chamber; the conditioner is at least one of the sludge pyrolysis or incineration residues, and the proportion of the conditioner added is 5%-10% of the weight of the wet sludge; an upper filter cloth reel and a lower filter cloth reel are provided at one end of the heated pre-dehydration chamber, which are used in conjunction with the upper and lower filter cloths respectively, and the upper filter cloth reel and the lower filter cloth reel can work forward for feeding and filter pressing dehydration, and can also work reversely for discharging; the upper filter cloth reel and the lower filter cloth reel are used ... A dewatered sludge storage bin is provided at the outlet of the filter cloth drum. An upper filter cloth discharging roller and a lower filter cloth discharging roller are provided at one end of the heating pre-dehydration chamber. The upper filter cloth discharging roller and the lower filter cloth discharging roller drag out the double-layer filter cloth by friction. A 40-60 mm insulation layer is provided in the heating pre-dehydration chamber. The bottom of the heating pre-dehydration chamber is an oblique flow plate. The lowest point of the oblique flow plate is a water collecting trough. The water collecting trough is drained outward through a drainage pipe. The circulating cloth mechanism includes a cyclic and repeated sliding roller to realize the stacking distribution of the double-layer filter cloth in the high-pressure dehydration trough, in preparation for subsequent high-pressure dehydration. The hydraulic cylinder is connected to the hydraulic hammer through a hydraulic telescopic rod. The hydraulic hammer is facing the high-pressure dehydration trough. A drainage interlayer is formed between the filter cloth accommodating cavity and the inner wall of the high-pressure dehydration trough. The four walls of the filter cloth accommodating cavity and the bottom There are mesh-shaped drainage holes evenly distributed, and the water squeezed out of the multiple layers of filter cloth flows into the drainage interlayer, and the drainage interlayer is drained outward through the drainage pipe; one side of the upper filter cloth reel and the lower filter cloth reel is correspondingly provided with an upper filter cloth scraper and a lower filter cloth scraper, one end of each scraper is fixed by a hinge, and the other end is preloaded by a spring to make the scraper close to the outer surface of the filter cloth, and the upper filter cloth scraper and the lower filter cloth scraper are rectangular iron plates or angle irons; the outer sides of the upper and lower filter cloths are correspondingly provided with upper sliding rollers and lower sliding rollers, the upper sliding rollers are inclined and evenly distributed, and the lower sliding rollers are arranged horizontally, one by one; the included angle between the center lines of the two sliding rollers is less than 5 degrees; the added material is evenly spread on the filter cloth or filter belt, and the material thickness before entering the high-pressure dewatering tank is less than 3mm, characterized in that, The steps include: a) The sludge and the conditioning agent are mixed in a stirring tank, and the mixed material after stirring is transported to the feed port of the sludge dehydration and drying device; the conditioning agent is at least one of the sludge pyrolysis or incineration residues, and the addition ratio of the conditioning agent is 5%-10% of the weight of the wet sludge; b) The sludge flowing out of the feed port flows to the center line of the lower filter cloth, and is squeezed by two rows of multi-layer sliding rollers to be spread flat between the upper and lower filter cloths; c) In the heating pre-dehydration chamber, a flue gas inlet is provided at the bottom; hot flue gas enters from the flue gas inlet and is discharged from the flue gas outlet, heating and pre-dehydrating the filter cloth and the sludge sandwiched in the filter cloth, and at the same time, heating conditioning is achieved, and the dripping water flows from the inclined flow plate to the water collecting tank and is discharged through the drain pipe; the evaporated water is discharged together with the flue gas; the hot flue gas selects the waste flue gas generated by the pyrolysis or incineration process of the sludge; d) The sludge is pre-dehydrated and heated online at the same time; Then, the upper and lower filter cloths are gradually pulled out by the upper filter cloth discharging drag roller and the lower filter cloth discharging drag roller by friction; the circulating cloth mechanism folds the sandwich filter cloth circulating cloth in the high-pressure dewatering tank; e) After the high-pressure dewatering tank is filled with filter cloth, the feeding is stopped, and the hydraulic cylinder drives the hydraulic telescopic rod to push the hydraulic hammer to perform high-pressure dewatering on the multiple layers of filter cloth in the high-pressure dewatering tank; the four walls and the bottom of the receiving chamber in the high-pressure dewatering tank are all mesh outlets, so that the water is squeezed into the drainage interlayer; the filtered water in the drainage interlayer is discharged through the drainage pipe; f) After the sludge is dehydrated under high pressure in the two layers of filter cloth, the hydraulic cylinder drives the hydraulic telescopic rod to push the hydraulic hammer out of the high pressure dehydration tank; the upper filter cloth reel and the lower filter cloth reel roll in opposite directions, gradually dragging the double-layer filter cloth in the high pressure dehydration tank back to the heating pre-dehydration chamber; the two layers of filter cloth after high pressure and the sludge flakes in the middle are spread flat between the upper and lower rows of multi-layer sliding rollers, and are further heated and dried by the flue gas waste heat before discharge; g) At the same time, due to the reverse rolling of the upper filter cloth drum and the lower filter cloth drum, the sludge flakes are released, and the sludge is scraped into the dewatered sludge storage bin by the joint action of the upper filter cloth scraper and the lower filter cloth scraper, completing a sludge dewatering cycle; h) After the sludge high-pressure dewatering flakes are discharged, the sludge dewatering begins to enter the next cycle, the upper filter cloth drum and the lower filter cloth drum are rolled forward; at the same time, the upper filter cloth discharge roller and the lower filter cloth discharge roller are dragged forward; the mud pump again transports the sludge from the conveying pipe to the feed port in the sludge dewatering and drying device, and the next dewatering working cycle begins at the center line position of the lower filter cloth drum.

8. A sludge dehydration and drying method according to claim 7, characterized in that: The feed sludge stays in the heated pre-dehydration chamber for 10~15min; the high-pressure dehydration pressure is >3MPa, and the filtration time is >5min.

9. A sludge dehydration and drying method according to claim 7 or 8, characterized in that: The flue gas temperature at the inlet of the heating pre-dehydration chamber is 100~180℃, and the dehydrated sludge flakes stay in the heating chamber for 5~10 minutes before being discharged.

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