WO2020211506A1

WO2020211506A1 - Nested sludge low-temperature drying and granulation device and method thereof

Info

Publication number: WO2020211506A1
Application number: PCT/CN2020/073608
Authority: WO
Inventors: 翁焕新; 张微; 苏闽华; 许跃锋; 陈海燕
Original assignee: 浙江大学
Priority date: 2019-04-15
Filing date: 2020-01-21
Publication date: 2020-10-22
Also published as: CN110066089A

Abstract

A nested sludge low-temperature drying and granulation device, which is a dual-roller structure consisting of an inner roller (9) and an outer roller (10). The outer roller (10) is coaxially nested outside the inner roller (9), the two rollers are fixed by means of a plurality of circumferential support rods (24), and an annular cavity is formed between the two rollers. The planar space occupied by the device is one half smaller than a segmented sludge low-temperature drying device, so that the sludge drying efficiency can be decreased to 90-98%, and in the case that the time of the heat exchange reaction between sludge and flue gas is the same, the yield is 40-60% greater than that of segmented sludge low-temperature drying.

Description

Embedded sludge low-temperature drying and granulation device and method

Technical field

The invention belongs to the field of sludge treatment devices, and specifically relates to a mosaic type sludge low-temperature drying and granulation device and a method thereof.

Background technique

Urban sewage and industrial wastewater will produce a large amount of sludge during the purification process. This sludge not only contains pathogenic microorganisms, a variety of organic and inorganic pollutants and heavy metals, but also has a high water content and a large volume. Therefore, it is a kind of hazardous A huge amount of solid waste. How to deal with sewage treatment plant sludge economically and safely is a worldwide environmental problem. It is urgent for developing countries with large populations to solve this environmental problem. For example, the amount of sludge in China is particularly large, exceeding 100 million tons per year. (Water content of 80%), and increase at an annual growth rate of 10-15%, so there is no space for sludge landfill; in addition, due to the combined treatment of domestic sewage and industrial wastewater in China, the composition of sludge is very complicated. In particular, the content of heavy metals is so high that it cannot be used in land.

The harmlessness, reduction and resource treatment of sludge are the goals of the joint efforts of all countries in the world. To reduce the water content of sludge and reduce the volume of sludge, the first reduction of sludge is the ultimate realization of sludge The key to harmless and resource-based treatment. Practice has shown that "thermal drying" is the most effective method for deep dewatering and volume reduction of sludge. However, thermal drying of sludge is a process of net energy consumption, and energy consumption usually accounts for percent of the total cost of sludge treatment. More than 80, so there is a "energy bottleneck". At the same time, experimental studies have shown that when the drying temperature is greater than 300°C, some organic matter in the sludge will be pyrolyzed. This result not only causes the exhaust gas to contain a large amount of harmful gases and greatly increases the processing cost of the exhaust gas, but also because of the sludge. The reduction of organic matter content reduces the utilization value of sludge calorific value resources. Therefore, sludge drying must be carried out at low temperatures.

China's energy structure is dominated by coal. China's annual coal consumption exceeds 3.6 billion tons, accounting for about 66% of total domestic energy consumption. In the coming decades, China's overall coal consumption will remain at a relatively high level. The temperature of flue gas emitted by large and small thermal power plants throughout the country, as well as cement plants, waste incineration plants and coal-fired boilers, etc. is generally between 110 and 200 ℃. A large amount of energy is lost through the emission of flue gas in the form of waste energy. The huge potential contained in these exhausted flue gas is the most ideal heat source for low-temperature drying of sludge, especially when the waste heat of flue gas is used to dry the sludge, due to the use of hot flue gas and wet sludge. In direct contact, wet sludge can absorb more than 60% of PM _2.5 and more than 43% of PM ₁₀ in flue gas, and absorb 22-25% of sulfur dioxide and about 30% of nitrogen oxides in flue gas, so it has source control The effect of smog. Experimental studies have shown that under low temperature conditions (ie flue gas temperature of 110-200°C), to complete the sludge drying and granulation process, sufficient space and time are required to ensure that the hot flue gas and the wet sludge are separated In order to meet this condition, the existing low-temperature drying and granulation of sludge usually adopts a staged process. The volume of the equipment is often larger, and the infrastructure needs to occupy a larger land area. Therefore, in the concrete implementation of the low-temperature sludge drying project using flue gas waste heat or using independent self-provided heat source flue gas, the project implementing unit often lacks sufficient space and places the sludge drying and granulation system at low temperature. The auxiliary facilities are difficult to arrange in the plane space position, which will eventually affect the landing of the project.

In order to change the phenomenon that the low-temperature sludge drying project is difficult to implement due to the narrow space, the present invention provides a mosaic-type sludge low-temperature drying and granulation device and method thereof, which not only improves the efficiency of low-temperature sludge drying , And the process of sludge drying and granulation can be completed in a relatively minimal plane space, so that the area required for the low-temperature sludge drying project using flue gas waste heat or independent self-provided heat source flue gas is more than the original The area occupied by the low-temperature sludge drying project of the same scale has been reduced by more than one-half. This is to smoothly promote the low-temperature sludge drying technology, especially to make full use of the flue gas waste heat resources and completely overcome the sludge thermal drying. The “energy consumption bottleneck” of globalization has created favorable conditions.

Summary of the invention

The purpose of the present invention is to solve the problems existing in the prior art and provide a mosaic sludge low-temperature drying and granulation device and method thereof.

The specific technical scheme adopted by the present invention is as follows:

A mosaic type sludge low-temperature drying and granulation device, which comprises an inner drum and an outer drum. The outer drum is coaxially nested outside the inner drum, and the two drums are fixed and formed by several supporting rods. Annular cavity; the inner roller and outer roller are driven to rotate by the driving device;

The inner wall of the inner drum is provided with several rows of lifting plates arranged in the circumferential direction of the inner drum, and all the lifting plates in each row of lifting plates are evenly arranged from the front end to the rear end of the inner drum; The material plates all protrude from the inner wall of the inner drum, and are used to drive the sludge to rotate together during the rotation of the inner drum, and to make the sludge fall when it reaches the top area; the front end of the inner drum is provided with a first air inlet and The sludge inlet, the rear end is provided with a first sludge outlet, the first air inlet is connected to an external hot air source through a ventilation pipe, and the sludge inlet is connected to the sludge through a screw conveyor. The double screw quantitative sludge feeder at the bottom of the sludge storage bin, the first sludge discharge port is connected to the inner drum and the annular cavity; a sludge disperser is arranged in the inner drum near the sludge feed port;

One or more sludge moving guide plates are provided on the inner wall of the outer drum, and the sludge moving guide plate is a guide plate extending from the rear end to the front end of the outer drum in a spiral form; the front end of the outer drum is provided There is a second air inlet and a second sludge discharge outlet, the inner drum and the outer drum are provided with a common air outlet at the rear end; the second air inlet is connected to an external hot air source through a ventilation duct, and the second The sludge discharge port is connected to the sludge product warehouse through the sludge conveyor belt, and the air outlet is connected to the exhaust gas treatment equipment through the ventilation pipe and then connected to the chimney.

As a first preference, the external hot air source is a flue gas waste heat source, and the flue gas waste heat source is sequentially connected to the inlets of the multi-tube cyclone dust collector, the first induced draft fan and the ventilation pipe through a pipe with an electric gate valve.

Further, the exhaust gas treatment equipment is a dust removal and desulfurization device, and the gas after treatment in the dust removal and desulfurization device is discharged through the chimney under the traction of the second induced draft fan.

Further, the flue gas waste heat source is the flue gas discharge port of thermal power plants, cement plants, garbage incineration plants, and boilers.

As a second preference, the external hot blast source is a hot blast stove, and the hot blast outlet of the hot blast stove is connected to the inlet of the temperature regulating device and the ventilation pipe in turn through a pipe.

Further, the exhaust gas treatment equipment is a multi-stage dust removal device, and the treated gas in the multi-stage dust removal device is discharged through the chimney to meet the standard under the traction of the third induced draft fan.

Preferably, the sludge storage bin is an underground sludge storage bin.

Preferably, the sludge conveyor belt is a closed sludge conveyor belt.

As a third preference, the inner drum is sequentially divided into a feeding zone, a first lifting zone, a dispersion zone, a second lifting zone and a third lifting zone along the axial direction;

In the feeding zone, a feeding thread is provided along the inner wall of the inner drum for conveying the sludge input from the sludge feeding port to the first lifting zone;

One or more rows of the lifting plates are provided in the first lifting zone, the second lifting zone, and the third lifting zone; the lifting plates are formed by splicing the first steel plate and the second steel plate Angle plate form, in which the side of the first steel plate is fixed on the inner wall of the inner drum, the second steel plate is fixed and overlapped with the side of the first steel plate, and the second steel plate is located in the inner cavity of the inner drum and faces the side of the inner drum rotation direction Tilt, so that the sludge inside the inner drum is lifted by the lifting plate during the rotation process, and falls down at a high place; and the material in the first lifting zone, the second lifting zone, and the third lifting zone The angles of the plates decrease successively; each lifting plate in the inner drum has an inclined slope toward the first sludge discharge port, so that the sludge can gradually move toward the first sludge discharge port during the rotation of the lifting plate Move on one side

The sludge disperser is arranged in the dispersing area, and the sludge disperser is at least one row of chains, each row of chains is arranged circumferentially along the inner wall of the inner drum, and both ends of each chain are fixed on the inner wall of the inner drum , And the distance between the fixed ends is less than the length of the chain, so that the chain can crush the internal sludge during the rotation of the inner drum;

The first sludge discharge port is arranged at the end of the third lifting zone.

Further, the folding angle of the lifting plate in the first lifting zone is 130-140°, the folding angle of the lifting plate in the second lifting zone is 115-125°, and the folding angle of the lifting board in the third lifting zone It is 100～110°.

Further, the cylinder diameter of the inner drum is 1.5-3.0m, and the axial length is 10-25m; the first steel plate fixed to the inner wall of the inner drum in each lifting plate is 100-120 cm in length and width It is 19-24 cm, and the first steel plate is installed perpendicularly to the inner wall of the inner drum, and the second steel plate has a length of 100-120 cm and a width of 10-12 cm.

Further, the cylinder diameter of the outer drum is 3.0-5.0m, and the axial length is 10-25m;

Further, in the first, second, and third lifting areas, each row of lifting plates has 16-20 lifting plates, and each row of lifting plates runs along the circumference of the inner drum. Arrange to equal angles.

Further, in the dispersing zone, the sludge disperser has 1 to 2 rows of chains, and each row of chains is arranged at an equal angle of 20-25° along the circumferential direction of the inner wall of the inner drum.

Further, the length of the chain is 115-125 cm, the two ends of the chain are welded and fixed to the inner wall of the inner drum, and the distance between the two welding points is not more than 90-100 cm.

Further, when the chain is installed, the fixed ends on both sides also have an inclined slope toward the first sludge discharge port, so that the sludge at the bottom of the inner drum can gradually move toward the first sludge discharge port during the rotation process of the inner drum. Move on one side.

Another object of the present invention is to provide a method for low-temperature drying and granulation of sludge using the drying and granulation device in the first preferred mode, the second preferred mode, and the third preferred mode. The method will be described in detail through subsequent examples.

Compared with the prior art, the present invention has the following beneficial effects:

1) Using the waste heat of flue gas to dry the sludge can reduce the water content of the sludge of the sewage treatment plant to less than 30% by weight without consuming new energy, reducing the volume of the sludge to one-third Below one, completely overcome the "energy bottleneck" of thermal drying of sludge.

2) The inlaid sludge low-temperature drying device occupies a one-half of the plane space occupied by the original segmented low-temperature sludge drying device, which has changed the thermal power plant, cement plant, waste incineration plant, etc. due to the narrow ground space However, it is difficult to implement the project of using flue gas waste heat to dry sludge.

3) The drying method in which wet sludge is in direct contact with hot flue gas not only maximizes the efficiency of sludge drying, but more importantly, the sludge can absorb and absorb a large amount of PM _2.5 , PM ₁₀ and the flue gas. Sulfur dioxide and nitrogen oxides play a role in controlling the source of air pollution.

4) Since the present invention changes the low-temperature sludge drying from the original segmented type to the mosaic type, the sludge dispersion and drying process (equivalent to the original first-stage drying) is carried out in a fully enclosed state, not only The cylinder of the sludge dispersion and drying equipment does not lose energy due to exposure and cooling, and the sludge dispersion and drying equipment are heated at the same time inside and outside the cylinder. Therefore, the efficiency of sludge drying can be changed from the original segmented type. The 60-85% of the sludge is increased to 90-98%. When the heat exchange reaction between the sludge and the flue gas takes the same time, the low-temperature drying of the embedded sludge increases the output by 40% compared with the low-temperature drying of the staged sludge. -60%.

5) The present invention divides the inner drum into multiple zones. By setting the dispersion area in the middle and setting up the lifting plates with successively decreasing angles in the first lifting area, the second lifting area and the third lifting area, it greatly improves The drying efficiency of sludge.

Description of the drawings

Figure 1 is a schematic diagram of a mosaic type sludge low-temperature drying and granulation device;

Figure 2 is a schematic cross-sectional view of the inner drum after installing the lifting plate;

Figure 3 is a schematic diagram of the sludge moving guide plate in the outer drum;

Figure 4 is a schematic structural diagram of another embedded sludge low-temperature drying and granulation device;

5 is a schematic diagram of the structure of the inner drum in Embodiment 3;

Figure 6 is a schematic diagram of the structure of the lifting plate in embodiment 3;

Figure 7 is a schematic diagram of the installation of a row of lifting plates in the inner drum in Embodiment 3.

Reference signs in the figure: flue gas waste heat source 1, electric gate valve 2, multi-tube cyclone dust collector 3, first induced draft fan 4, first air inlet 5, ventilation duct 6, sludge inlet 7, second inlet Air port 8, inner drum 9, outer drum 10, lifting plate 11, sludge disperser 12, first sludge discharge port 13, sludge moving guide plate 14, air outlet 15, dust removal and desulfurization device 16, second Induced draft fan 17, screw conveyor 18, double screw quantitative sludge feeder 19, buried sludge storage bin 20, closed sludge conveyor belt 21, sludge product warehouse 22, chimney 23, support rod 24, hot blast stove 25, The temperature regulating device 26, the multi-stage dust removal device 27, the third induced draft fan 28, and the second sludge discharge port 29.

detailed description

The present invention will be further elaborated and illustrated below in conjunction with the drawings and specific embodiments.

Example 1

As shown in Figure 1, it is the inlaid sludge low-temperature drying and granulation device in the first embodiment. Its core is a double drum structure composed of an inner drum 9 and an outer drum 10. The outer drum 10 is coaxially nested in Outside the inner drum 9, the two drums are fixed by a plurality of circumferential support rods 24, and an annular cavity is formed between the two drums. The outer shape of the inner drum 9 and the outer drum 10 are both elongated cylinders. The diameter of the inner drum 9 is 1.5～3.0m and the length is 8～25m; the diameter of the outer drum 10 is 3.0～5.0m. The length is 8-25m, and it is set according to actual needs. The outer diameter of the inner drum 9 must be smaller than the inner diameter of the outer drum 10. The sludge is dispersed and dried in the inner drum 9 and dried and granulated in the outer drum 10 a second time.

The inner drum 9 and the outer drum 10 are driven to rotate synchronously by a driving device. The driving device can be realized by using a frequency-modulated motor with a reducer. Of course, other equipment that can drive the drum to rotate can also be used. The inner wall of the inner drum 9 is provided with 4 to 8 rows of lifting material plates 11, and the 4 to 8 rows of lifting material plates 11 are arranged at equal intervals along the circumferential direction of the inner drum 9. All the lifting plates 11 in each row of lifting plates 11 are evenly arranged from the front end to the rear end of the inner drum 9. As shown in FIG. 2, it is a case where 4 rows of lifting material plates 11 are provided. Each lifting plate 11 protrudes from the inner wall of the inner drum 9. During the rotation of the inner drum 9, the sludge is driven to rotate, and when it reaches a certain height area on the top, the sludge is separated from the lifting plate 11 under the action of gravity and falls, and falls on the sludge on the lifting plate 11 below. The mud continues to be driven by other lifting plates 11 to rotate. In order for the sludge to move axially along the inner drum 9, it is best to install the lifting plate 11 obliquely, that is, the plate surface of the lifting plate 11 is inclined at the end of the inner drum 9, so the sludge in the inner drum 9 During the rotation driven by 11, the sludge will gradually slide along the inclined surface, and then fall, so that the whole gradually moves toward the end of the inner drum 9. The front end of the inner drum 9 is provided with a first air inlet 5, a sludge inlet 7 is provided above the front end, and a first sludge outlet 13 is provided on the bottom surface of the rear end of the inner drum (ie, the cylindrical side surface of the inner drum). Among them, the first air inlet 5 is connected to an external hot air source through a ventilation pipe 6. In this embodiment, the external hot air source is flue gas waste heat source 1, which can be thermal power plants, cement plants, waste incineration plants, boilers and other facilities with waste heat flue gas. The flue gas exhaust port. The flue gas waste heat source 1 is connected to the inlets of the multi-tube cyclone dust collector 3, the first induced draft fan 4, and the ventilation pipe 6 through a pipe with an electric gate valve 2 in sequence. Under the traction of the first induced draft fan 4, the flue gas with waste heat discharged from the flue gas waste heat source 1 can enter the ventilation duct 6, and then enter the two drums for drying sludge. The sludge is input from the sludge inlet 7, and the sludge inlet 7 is connected to a double screw quantitative sludge feeder 19 installed at the bottom of the buried sludge storage bin 20 through a screw conveyor 18. A sludge disperser 12 is provided in the inner drum (9) near the sludge inlet for preliminary dispersion of the sludge input from the sludge inlet 7. The sludge disperser 12 can be realized by using a dispersing device in the prior art, or a steel chain or chain hammer. The first sludge discharge port 13 communicates with the inner drum 9 and the annular cavity between the two drums. The sludge that has been initially dried by the inner drum 9 falls from the first sludge discharge port 13 and enters the two drums The annular cavity in between continues to dry.

One or more sludge moving guide plates 14 are provided on the inner wall of the outer drum 10. As shown in FIG. 3, the sludge moving guide plate 14 is a guide plate extending from the rear end to the front end of the outer drum 10 in a spiral form, forming a spiral conveying structure. The front end of the outer drum 10 is provided with a second air inlet 8 and a second sludge discharge port 29. The rear end of the inner drum 9 and the outer drum 10 are provided with a common air outlet 15, and the second air inlet 8 passes through the ventilation duct 6 Connect the flue gas waste heat source 1. The second sludge discharge port 29 is arranged on the bottom surface of the front end of the outer drum 10 (ie, the cylindrical side of the outer drum), and is connected to the sludge product warehouse 22 through a closed sludge conveyor belt 21, and the air outlet 15 is equipped with an electric gate valve The ventilation pipe 6 of 2 is connected to the exhaust gas treatment equipment and then connected to the chimney 23. In this embodiment, the exhaust gas processing equipment is the dust removal and desulfurization device 16, and the gas after treatment in the dust removal and desulfurization device 16 is discharged through the chimney 23 under the traction of the second induced draft fan 17 to reach the standard.

The low-temperature drying and granulation method of sludge based on the drying and granulation device has the following steps:

1) Sewage treatment plant sludge with a moisture content of 80% or more of the total weight by mass is transported and stored in the sludge storage bin 20 by a closed sludge transport vehicle;

2) Through the double screw quantitative sludge feeder 19 installed at the bottom of the sludge storage bin 20, the divided sludge is uniformly and continuously fed into the inner drum 9 through the sludge inlet 7 by the screw conveyor 18;

3) The flue gas discharged from thermal power plants, cement plants, waste incineration plants or boilers at a temperature of 120°C to 200°C passes through the multi-tube cyclone dust collector 3 to remove particles ≥PM ₁₀ in the flue gas, and then passes through the first induced draft fan 4 The first air inlet 5 is fed into the inner drum 9, and the opening degree of the damper is adjusted through the electric gate valve 2 to control the flue gas flow, so that the sludge input in the inner drum 9 and the flue gas input are matched synchronously;

4) Driven by the driving device, rotate the inner drum 9 clockwise at the set speed without interruption, so that the wet sludge in the inner drum 9 is in direct contact with the hot flue gas, and the sludge absorbs heat from the flue gas While evaporating the water, it absorbs the fine particles of PM _2.5 and PM _10, sulfur dioxide and nitrogen oxides in the flue gas, and wraps them in the particles. Under the combined action of the sludge disperser 12 and the lifting plate 11, The sludge is dispersed into smaller blocks, so that the wet sludge and hot flue gas can fully contact each other in the sludge dispersion and drying equipment for heat exchange reaction;

5) In the inner drum 9, the sludge is pushed to gradually move from the front end to the rear end. When the moisture content of the sludge drops below 60%, it enters the outer drum 10 from the first sludge outlet 13 at the rear end;

6) Driven by the driving device, rotate the outer drum 10 clockwise without interruption at the set speed, and use the sludge moving guide plate 14 to push the sludge falling from the inner drum 9 to move from the rear end to the front end; The hot flue gas is sent from the second air inlet 8 into the outer drum 10, and in the annular cavity between the inner drum 9 and the outer drum 10, the hot flue gas and the sludge continue to directly contact for heat exchange reaction. The moisture content of the sludge drops below 40% and naturally forms sludge particles with a particle size of 2-8 mm, which are output from the second sludge discharge port 29 below the front end and sent into the sludge by the sludge conveyor 21 The finished product warehouse 22 is cooled. When the sludge particles are cooled to room temperature, the moisture content drops to <30%, the volume is reduced to less than one third of the original volume, and 95% of the original heating value is preserved. It can be used as an auxiliary fuel to be mixed with coal. Burning, it can also be used as a raw material for cement, or burned light energy-saving bricks, ceramsite and other resources;

7) The flue gas exhaust after sludge drying is drawn from the air outlet 15 of the inner drum 9 and the outer drum 10 through the second induced draft fan 17, and sent to the dust removal and desulfurization device 16 for dust removal and desulfurization. After treatment, the chimney 23 reaches the standard emission. The odorous gas released by the sludge storage warehouse and the sludge product warehouse is sent to the biological filter bed for unified treatment through the gas collection system, or sent to the hot air furnace for high temperature treatment. The whole process of sludge treatment is carried out under fully enclosed and fully automatic control to achieve clean production.

8) The dried sludge particles (average calorific value of about 2000kcal/kg) can be used as auxiliary fuels, and can also be used as raw materials for cement production and as building materials such as ceramsite and lightweight bricks, so as to truly achieve sludge-free Harmful and resourceful treatment.

In this embodiment, the plane space occupied by the embedded low-temperature sludge drying device is reduced by one-half compared with the original segmented low-temperature sludge drying device. Moreover, because the present invention changes the low-temperature sludge drying from the original segmented type to the mosaic type, the sludge dispersion and drying process (equivalent to the original first-stage drying) is carried out in a fully enclosed state, which not only makes the sludge The cylinder of the sludge dispersion and drying equipment will not lose energy due to exposure and cooling, and the sludge dispersion and drying equipment can be heated simultaneously inside and outside the cylinder. For the inner drum, there is no heat dissipation, but heat will be input to it from the outer drum, so the drying efficiency of the wet sludge is greatly improved. Tests have shown that, compared with segmented sludge drying and granulation, the device of the present invention can increase the efficiency of sludge drying from 60-85% of the original segmented sludge to 90-98%. When the heat exchange reaction between sludge and flue gas takes the same time, the output of the embedded sludge low-temperature drying is 40-60% higher than that of the staged sludge low-temperature drying.

Example 2

As shown in FIG. 4, in this embodiment, another embedded sludge low-temperature drying and granulation device is provided, which also includes the same inner drum 9 and outer drum 10. The outer roller 10 is coaxially nested outside the inner roller 9, and the two rollers are fixed by a plurality of circumferential support rods 24, and an annular cavity is formed between the two rollers. The outer drum 9 and the outer drum 10 are both elongated cylinders. The diameter of the inner drum 9 is 1.5～3.0m and the length is 8-25m. The diameter of the outer drum 10 is 3.0～5.0m. The length is 8-25m, which can be set according to actual needs. The sludge is dispersed and dried in the inner drum 9, and the second drying and granulation is carried out in the outer drum 10.

The inner drum 9 and the outer drum 10 are driven to rotate synchronously by a driving device. The driving device can be realized by using a frequency-modulated motor with a reducer. Of course, other equipment that can drive the drum to rotate can also be used. The inner wall of the inner drum 9 is provided with 4 to 8 rows of lifting material plates 11, and the 4 to 8 rows of lifting material plates 11 are arranged at equal intervals along the circumferential direction of the inner drum 9. All the lifting plates 11 in each row of lifting plates 11 are evenly arranged from the front end to the rear end of the inner drum 9. As shown in FIG. 2, it is a case where 4 rows of lifting material plates 11 are provided. Each lifting plate 11 protrudes from the inner wall of the inner drum 9. During the rotation of the inner drum 9, the sludge is driven to rotate together, and when it reaches a certain height area on the top, the sludge is separated from the lifting plate under the action of gravity. 11 falls, and then continues to be driven by other lifting plates 11 to rotate. In order for the sludge to move along the axial direction of the inner drum 9, it is better to install the lifting plate 11 obliquely, that is, the surface of the lifting plate 11 is inclined at the end of the inner drum 9, and the sludge will gradually move toward the inner drum 9 due to this inclined slope. The end moves. The front end of the inner drum 9 is provided with a first air inlet 5, a sludge inlet 7 is provided above the front end, and a first sludge outlet 13 is provided on the bottom surface of the rear end of the inner drum (ie, the cylindrical side surface of the inner drum). Wherein, the first air inlet 5 is connected to an external hot air source via a ventilation pipe 6. In this embodiment, the external hot air source is a hot blast stove 25, and the energy source is coal or natural gas or oil. The hot air outlet of the hot blast stove 25 is connected to the inlet of the temperature regulating device 26 and the ventilation duct 6 through a pipe, and the temperature of the hot air can be changed by the temperature regulating device 26. The hot air discharged from the hot blast stove 25 can enter the ventilation duct 6 and then enter the two drums for drying the sludge. The sludge is input from the sludge inlet 7, and the sludge inlet 7 is connected to a double screw quantitative sludge feeder 19 installed at the bottom of the buried sludge storage bin 20 through a screw conveyor 18. The first sludge discharge port 13 communicates with the inner drum 9 and the annular cavity between the two drums. The sludge that has been preliminarily dried by the inner drum 9 falls from the first sludge discharge port 13 into the outer drum 10. Drying and granulation continue in the annular cavity between the inner drum 9 and the outer drum 10.

One or more sludge moving guide plates 14 are provided on the inner wall of the outer drum 10. As shown in FIG. 3, the sludge moving guide plate 14 is a guide plate extending from the rear end to the front end of the outer drum 10 in a spiral form, forming a spiral conveying structure. The front end of the outer drum 10 is provided with a second air inlet 8 and a second sludge discharge port 29. The rear end of the inner drum 9 and the outer drum 10 are provided with a common air outlet 15, and the second air inlet 8 passes through the ventilation duct 6 Connect the hot air stove 25. The second sludge discharge port 29 is arranged on the bottom surface of the front end of the outer drum 10 (ie, the cylindrical side of the outer drum), and is connected to the sludge product warehouse 22 through a closed sludge conveyor belt 21, and the air outlet 15 passes through an electric gate valve 2 The ventilation duct 6 is connected to the exhaust gas treatment equipment and then connected to the chimney 23. In this embodiment, the exhaust gas processing equipment is a multi-stage dust removal device 27, and the gas processed in the multi-stage dust removal device 27 is discharged through the chimney 23 under the traction of the third induced draft fan 28 to meet the standards.

The low-temperature drying and granulation method of sludge based on the above drying and granulation device has the following steps:

3) Use the hot air stove 25 to generate hot air, and then adjust the hot air to a suitable temperature by the temperature adjusting device 26, and send it into the inner drum 9 through the first air inlet 5 from the ventilation duct 6 and adjust the opening degree of the air door through the electric gate valve 2 Control the flow of flue gas, so that the sludge input in the inner drum 9 and the flue gas input are matched synchronously;

4) Driven by the driving device, rotate the inner drum 9 in a clockwise direction without interruption at the set speed to make the wet sludge directly contact the hot air. The sludge absorbs heat from the hot air to evaporate the moisture and absorb the smoke. The fine particles of PM _2.5 and PM ₁₀ in the atmosphere, sulfur dioxide and nitrogen oxides, and package them in the particles, under the combined action of the sludge disperser 12 and the lifting plate 11, the sludge becomes smaller and dispersed Block, so that the wet sludge and hot air can fully contact each other in the inner drum 9 for heat exchange reaction;

6) Driven by the driving device, rotate the outer drum 10 clockwise without interruption at the set speed, and use the sludge moving guide plate 14 to push the sludge falling from the inner drum 9 to move from the rear end to the front end; The hot air is fed into the outer drum 10 from the second air inlet 8. In the annular cavity between the inner drum 9 and the outer drum 10, the hot air continues to directly contact the sludge for heat exchange reaction. When the sludge contains water The rate drops below 40% and naturally forms sludge particles with a particle size of 2-8 mm, which are output from the second sludge discharge port 29 on the bottom of the front end, and sent to the sludge product warehouse 22 by the sludge conveyor belt 21. Cooling, when the sludge particles are cooled to room temperature, the moisture content will drop to <30%, the volume will be reduced to less than one-third of the original volume, and 95% of the original calorific value will be preserved. It can be used as an auxiliary fuel to be mixed with coal, or Used as a raw material for cement, or fired light energy-saving bricks, ceramsite and other resources;

7) After the sludge is dried, the hot air exhaust is drawn out from the air outlet 15 of the inner drum 9 and the outer drum 10 through the third induced draft fan 28, and sent to the multi-stage dust removal device 27 for multi-stage dust removal. After treatment, it is discharged from the chimney 23 Compliance emission. The odorous gas released by the sludge storage warehouse and the sludge product warehouse is sent to the biological filter bed for unified treatment through the gas collection system, or sent to the hot air furnace for high temperature treatment. The whole process of sludge treatment is carried out under fully enclosed and fully automatic control to achieve clean production.

Similarly, in this embodiment, the plane space occupied by the embedded sludge low-temperature drying device can also be greatly reduced. Moreover, the device can increase the efficiency of sludge drying from 60-85% of the original segmented type to 90-98%. Under the condition that the heat exchange reaction between sludge and flue gas has the same time, the embedded sludge is low temperature Compared with staged sludge drying, the output of low-temperature drying can be increased by 40-60%. Moreover, compared to the equipment of Example 1, the device can change the temperature of the hot air through the temperature adjustment device 26, can treat sludge with a higher water content, and can also adapt to sludge of different properties through temperature adjustment.

Example 3

In this embodiment, on the basis of the foregoing embodiment 1 or 2, the specific structure in the inner drum 9 is further optimized to improve the effect of sludge drying.

In this embodiment, as shown in Figure 5, the inner drum 9 adopts a multi-zone design, that is, it is sequentially divided into a feeding zone I, a first lifting zone II, a dispersion zone III, and a second lifting zone IV along the axial direction. And the third lifting zone V. It should be noted that the feeding zone I, the first lifting zone II, the dispersing zone III, the second lifting zone IV, and the third lifting zone V of the inner drum 9 can be integrally formed, and design components are not necessary. Asanas, which are merely functional divisions.

There are feeding threads along the inner wall of the inner drum 9 in the feeding zone I. The feeding threads are similar to the structure of the movable guide plate 14 in the outer drum 10. A spiral conveying structure is formed by multiple threads with a certain height. Driven by the structure, the sludge input from the sludge inlet 7 can be transferred to the first lifting zone II. The first sludge discharge port 13 is arranged at the end of the third lifting zone (V).

One or more rows of lifting plates 11 are provided in the first lifting zone II, the second lifting zone IV, and the third lifting zone V. As shown in Fig. 6, each lifting plate 11 in this embodiment is formed by splicing a first steel plate and a second steel plate into a corner-folded plate, and the corner of the first steel plate and the second steel plate is denoted as α. One side of the first steel plate is fixed on the inner wall of the inner drum 9, the second steel plate and the side of the first steel plate are overlapped and fixed, and the overlapped side and the side fixed on the inner wall of the inner drum 9 are a set of opposite sides. The second steel plate and the first steel plate can be integrally formed and bent, or two steel plates can be welded and fixed. As shown in Figure 7, the inner drum 9 rotates clockwise, and the second steel plate is located in the inner cavity of the inner drum 9 and is inclined toward the side of the rotation direction of the inner drum 9, so that the sludge inside the inner drum 9 is lifted during the rotation. The material plate 11 drives the lifting. When it is raised to a certain height, the friction between the sludge and the lifting plate 11 is not enough to support it to overcome the gravity, so the sludge will overcome the friction and fall from a high place, and then be lifted by the lifting plate 11 below. Drive up again. Similar to the foregoing embodiment, each lifting plate 11 in the inner drum 9 has an inclined slope toward the first sludge discharge port 13, so that the sludge can gradually move toward the first sludge during the rotation of the lifting plate 11. The sludge discharge port 13 moves on one side.

In addition, the sludge disperser 12 is arranged in the dispersing zone III, and the sludge disperser 12 has 1 to 2 rows of chains, and each row of chains is arranged circumferentially along the inner wall of the inner drum 9, and both ends of each chain are fixed in the inner On the inner wall of the drum 9, and the distance between the fixed ends is smaller than the length of the chain, so that the chain can crush the sludge inside the drum 9 during the rotation. The chain is made up of multiple iron rings in series, so the sludge will be tangled and broken between the iron rings during the rotation. At the same time, because the length of the chain is greater than the distance between the fixed ends of its two ends, it has a certain The swing space, when the inner drum 9 rotates to a certain height, will quickly slide down or swing under the action of gravity, and hammer and crush the sludge mass below.

In this embodiment, the folding angles of the lifting plate 11 in the first lifting zone II, the second lifting zone IV, and the third lifting zone V decrease successively, and the folding angle α of the lifting plate 11 in the first lifting zone II It is 130-140°, the folding angle α of the lifting plate 11 in the second lifting zone IV is 115-125°, and the folding angle α of the lifting plate 11 in the third lifting zone V is 100-110°. The purpose of this is to cooperate with the chain in the dispersion zone III to dry and disperse the sludge as efficiently as possible. The hoisting plate 11 in the first hoisting zone II has the largest folding angle, because the wet sludge that has just entered the inner drum 9 has greater viscosity. If the angle is too small, it will be difficult to move from height to the height of the hoisting plate 11 when the angle is too small. Falling down will affect the drying effect. Therefore, a larger angle can make it smoothly lift and fall. The sludge after drying in the first lifting zone II is still in the form of large blocks. If these larger sludge blocks directly enter the rear lifting zone, the drying efficiency will be caused by the excessive size of the block. Is too low. Therefore, the present invention sets a dispersion zone III behind the first lifting zone II to crush and disperse the large pieces of sludge so that it enters the rear lifting zone with a smaller block, so that the sludge The wet sludge inside the block can directly contact the high temperature flue gas. The angles of the lifting plate 11 in the second lifting zone IV and the third lifting zone V decrease successively, because as the volume of the sludge block decreases and the degree of drying increases, its viscosity will become smaller and smaller, so if the angle is folded If it is too large, it cannot be raised to a higher height, and will fall at a lower height. The lifting plate 11 with successively decreasing angles can better adapt to changes in the degree of sludge drying and block size.

In this embodiment, the parameters of each component in the inner drum 9 can be preferably set as follows: the length L of the first steel plate fixed to the inner wall of the inner drum 9 in each lifting plate 11 is 100-120 cm, and the width W is 19-24 The length L of the second steel plate is 100-120 cm, and the width H is 10-12 cm. In addition, in the first lifting zone II, the second lifting zone IV, and the third lifting zone V, each row of lifting plates 11 has 16 to 20 lifting plates 11, and each row of lifting plates 11 The inner drum 9 is arranged at equal angles in the circumferential direction, and the angle β between the adjacent lifting plates 11 is between 15 and 25°. In the dispersion zone III, the sludge disperser 12 is composed of 1 to 2 rows of chains, and each row of chains is arranged along the inner wall of the inner drum 9 at an equal angle of 20-25°. The length of the chain is 115-125 cm, and the two ends of the chain are welded to the inner wall of the inner drum 9 and the distance between the two welding points is not more than 90-100 cm.

In addition, when the chain in this embodiment is installed, the fixed ends on both sides are also preferably the same as the lifting plate 11, with an inclined slope toward the first sludge discharge port 13, so that the sludge at the bottom of the inner drum 9 is It can gradually move toward the side of the first sludge discharge port 13 during the driving rotation. Of course, since the feed zone I will continuously transport sludge, the sludge can barely be pushed forward without the inclined slope of the chain, but the inclined slope can ensure smoother advancement. The inclination gradient of the chain can be the same as the inclination angle of the lifting plate 11 or greater.

1) Store the sewage treatment plant sludge with a moisture content of 70% to 80% or more in the total weight mass percentage in the sludge storage bin 20;

3) The flue gas discharged from thermal power plants, cement plants, garbage incineration plants or boilers with a temperature of 110℃～200℃, passes through the multi-tube cyclone dust collector 3 to remove particles ≥ PM ₁₀ in the flue gas, and then passes through the first induced draft fan 4 The first air inlet 5 is sent into the inner drum 9, or hot air is generated by a hot blast stove 25, and then the hot air is adjusted to an appropriate temperature by the temperature adjusting device 26, and is sent into the inner drum through the ventilation duct 6 through the first air inlet 5 In 9, the opening degree of the air door is adjusted through the electric gate valve 2 to control the flow of flue gas, so that the sludge input volume in the inner drum 9 and the flue gas input volume are matched synchronously;

4) Driven by the driving device, rotate the inner drum 9 and the outer drum 10 clockwise without interruption at the set speed, so that the wet sludge in the inner drum 9 passes through the feeding zone I and the first lifting zone in turn Ⅱ. Dispersion zone Ⅲ, second lifting zone Ⅳ, third lifting zone Ⅴ and first sludge discharge port 13. After the wet sludge enters the first lifting zone Ⅱ through feeding zone I, it is lifted The plate 11 drives the top of the inner drum 9 to rotate. When the wet sludge rotates to a certain height, it will fall off the lifting plate 11 and fall back to the lifting plate 11 below. When the sludge moves to the dispersion zone III, The chain of the sludge disperser 12 is continuously entangled and hammered, and is broken and dispersed into smaller blocks; then the broken and dispersed small sludge blocks pass through the second lifting zone IV and the third lifting zone V successively. , Gradually become granular, so that the wet sludge and hot flue gas can be fully contacted with each other in the sludge dispersing and drying equipment for heat exchange reaction to complete rapid drying; in this process, the wet sludge is removed from While absorbing heat in the flue gas to evaporate the moisture to complete the preliminary drying, it absorbs and absorbs PM _2.5 , PM ₁₀ fine particles, sulfur dioxide and nitrogen oxides in the flue gas, and wraps them in the particles;

5) The moisture content of the sludge in the inner drum 9 drops below 60% and enters the outer drum 10 from the first sludge discharge port 13 at the rear end;

6) Driven by the driving device, rotate the outer drum 10 and the inner drum 9 clockwise without interruption at the set speed, and the sludge movement guide plate 14 in the outer drum (10) pushes the sludge falling from the inner drum 9 The mud moves from the rear end to the front end; at the same time, the hot flue gas is sent into the outer drum 10 from the second air inlet 8. In the annular cavity between the outer drum 10 and the inner drum 9, the hot flue gas and the sludge Continue to directly contact for heat exchange reaction. When the moisture content of the sludge drops below 40% and naturally form sludge particles with a particle size of 2-8 mm, they are output from the second sludge discharge port 29 on the bottom of the front end. The sludge conveyor belt 21 is sent to the sludge product warehouse 22 for cooling. When the sludge particles are cooled to room temperature, the moisture content drops to <30%, the volume is reduced to less than one third of the original volume, and 95% of the original calorific value is preserved ；

7) The flue gas exhaust after sludge drying is drawn from the air outlet 15 of the inner drum 9 and the outer drum 10 through the second induced draft fan 17, and sent to the dust removal and desulfurization device 16 for dust removal and desulfurization. After treatment, the chimney 23 reaches the standard emission. The odorous gas released from the sludge storage warehouse and the sludge product warehouse is sent to the biological filter bed for unified treatment through the gas collection system, or sent to the hot blast stove for high temperature treatment. In the case of using the hot air stove 25 to generate hot air for drying, the hot air exhaust after the sludge drying can be drawn from the air outlet 15 of the inner drum 9 and the outer drum 10 through the third induced draft fan 28, and sent The multi-stage dust removal device 27 is discharged from the chimney 23 after being multi-staged. The whole process of sludge treatment is carried out under fully enclosed and fully automatic control to achieve clean production.

8) The dried sludge particles (with an average calorific value of about 2000kcal/kg) can be used as auxiliary fuel to be mixed with coal, and can also be used as raw materials for cement production and for firing ceramsite, lightweight bricks and other building materials, thus realizing Harmless and resource treatment of sludge.

In order to prove the effect of the multi-zone design of the inner drum 9 on the sludge drying effect in this embodiment, multiple sets of test devices are designed for effect testing. The parameters used by the test device are as follows:

The cylinder of the inner drum 9 has a diameter of 2.5 m and a length of 18 m; the cylinder of the outer drum 10 has a diameter of 3.5 m and a length of 18 m. The length of the feeding zone I in the inner drum 9 is 1m, the length of the first lifting zone II is 3m, the length of the dispersion zone III is 2m, the length of the second lifting zone IV is 5m, and the length of the third lifting zone V is 7m. The first steel plate is 100 cm long and 20 cm wide, and the second steel plate is 100 cm long and 12 cm wide. In addition, in the first lifting zone II, the second lifting zone IV, and the third lifting zone V, each row of lifting plates 11 has 18 lifting plates 11, and each row of lifting plates 11 runs along the inner drum 9 are arranged at equal angles in the circumferential direction, and the center angle β between adjacent lifting plates 11 is between 20°. In the dispersing zone III, the sludge disperser 12 has two rows of chains, each of which has 18 chains, which are arranged at an equal angle of 20° along the circumferential direction of the inner wall of the inner drum 9 with each other. The length of the chain is 125 cm. The two ends of the chain are welded to the inner wall of the inner drum 9 and the distance between the two welding points is 90 cm.

The rest of the process parameters are kept the same, and three different sets of lifting plate angle setting methods are compared, and they are marked as A, B, and C respectively.

At the same time, in the above three groups of devices A to C, the dispersion zone III is located between the first lifting zone II and the second lifting zone IV. However, in order to show the influence of dispersing zone Ⅲ on the drying effect of sludge, another set of D devices is set up. The difference between D and C is only in the arrangement position of dispersing zone Ⅲ in inner drum 9, in D group Arrange the dispersion zone Ⅲ at the front end of the first lifting zone Ⅱ, that is, the sludge enters the dispersion zone Ⅲ from the feed zone I first, and then enters the first lifting zone Ⅱ, the second lifting zone Ⅳ, and the third lifting zone in turn District V.

Among the above four sets of devices, the moisture content of the sludge (before cooling) output from the second sludge discharge port 29 of the outer drum is shown in Table 1:

Table 1 Comparison of sludge drying efficiency at different angles of lifting plate

The comparison result of the above C combination and D group shows that the dispersing zone arrangement between the first lifting zone II and the second lifting zone IV can greatly improve the drying efficiency of sludge, but the dispersion zone is in front of the first lifting zone Before Ⅱ, the drying effect will decrease. This is mainly because the water content of the sludge before lifting is too high, and the sludge in the viscous state cannot be well broken by the iron chain, so the subsequent drying effect cannot be optimal.

In addition, the results of the above groups A to C show that the angles of the lifting plates 11 in the first lifting zone II, the second lifting zone IV, and the third lifting zone V are arranged in a manner that the size of the lifting plate 11 decreases in order to significantly increase the pollution. Mud drying efficiency.

The above-mentioned embodiment is only a preferred solution of the present invention, but it is not intended to limit the present invention. Those of ordinary skill in the relevant technical field can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, all technical solutions obtained by equivalent substitutions or equivalent transformations fall within the protection scope of the present invention.

Claims

A mosaic type sludge low-temperature drying and granulating device, which is characterized by comprising an inner drum (9) and an outer drum (10), and the outer drum (10) is coaxially nested outside the inner drum (9) , The two rollers are fixed by several support rods (24) and form an annular cavity; the inner roller (9) and the outer roller (10) are driven to rotate by the driving device;

The inner wall of the inner drum (9) is provided with several rows of lifting plates (11) arranged in the circumferential direction of the inner drum (9), and all the lifting plates (11) in each row of lifting plates (11) are The inner drum (9) is evenly arranged from the front end to the rear end; each lifting plate (11) protrudes from the inner wall of the inner drum (9) and is used to drive the sludge to rotate together during the rotation of the inner drum (9) , And make the sludge fall down when it goes to the top area; the front end of the inner drum (9) is provided with a first air inlet (5) and a sludge inlet (7), and the rear end is provided with a first sludge The discharge port (13), the first air inlet (5) is connected to an external hot air source through a ventilation pipe (6), and the sludge inlet (7) is connected and installed at the screw conveyor (18) The double screw quantitative sludge feeder (19) at the bottom of the sludge storage bin (20), the first sludge discharge port (13) is connected to the inner drum (9) and the annular cavity; the inner drum (9) ) Is provided with a sludge disperser (12) near the sludge inlet (7);

One or more sludge moving guide plates (14) are provided on the inner wall of the outer drum (10), and the sludge moving guide plates (14) are spirally moved from the rear end of the outer drum (10) to the front end An extended guide plate; the front end of the outer drum (10) is provided with a second air inlet (8) and a second sludge discharge port (29), and the inner drum (9) and the outer drum (10) are provided at the rear end There is a common air outlet (15); the second air inlet (8) is connected to an external hot air source through a ventilation pipe (6), and the second sludge outlet (29) passes through the sludge conveyor belt (21) ) Is connected to the sludge product warehouse (22), and the air outlet (15) is connected to the exhaust gas treatment equipment through the ventilation pipe (6) and then connected to the chimney (23).
The embedded sludge low-temperature drying and granulation device according to claim 1, characterized in that the external hot air source is a flue gas waste heat source (1), and the flue gas waste heat source (1) is provided with an electric gate valve The pipeline of (2) is sequentially connected to the inlets of the multi-tube cyclone dust collector (3), the first induced draft fan (4) and the ventilation pipe (6).
The embedded sludge low-temperature drying and granulation device according to claim 2, wherein the exhaust gas treatment equipment is a dust removal and desulfurization device (16), and the gas treated in the dust removal and desulfurization device (16) is Under the traction of the second induced draft fan (17), the discharge reaches the standard through the chimney (23).
The embedded sludge low-temperature drying and granulation device according to claim 2, wherein the flue gas waste heat source (1) is the flue gas discharge port of thermal power plants, cement plants, garbage incineration plants, and boilers.
The inlaid sludge low-temperature drying and granulation device according to claim 1, characterized in that the external hot air source is a hot blast stove (25), and the hot blast outlet of the hot blast stove (25) is connected in turn through a pipe to adjust the temperature The inlet of the device (26) and the ventilation duct (6).
The embedded sludge low-temperature drying and granulation device according to claim 5, wherein the exhaust gas treatment equipment is a multi-stage dust removal device (27), and the gas treated in the multi-stage dust removal device (27) Under the traction of the third induced draft fan (28), the discharge reaches the standard through the chimney (23).
The embedded sludge low-temperature drying and granulating device according to any one of claims 1 to 6, wherein the sludge storage bin (20) is an underground sludge storage bin.
The embedded sludge low-temperature drying and granulation device according to any one of claims 1 to 6, characterized in that the sludge conveyor belt (21) is a closed sludge conveyor belt.
The embedded sludge low-temperature drying and granulation device according to claim 1, characterized in that:

The inner drum (9) is divided into a feeding zone (I), a first lifting zone (II), a dispersion zone (Ⅲ), a second lifting zone (IV) and a third lifting zone in sequence along the axial direction. (Ⅴ);

A feeding thread is provided along the inner wall of the inner drum (9) in the feeding zone (I), which is used to transport the sludge input from the sludge feeding port (7) to the first lifting zone (II);

The first lifting zone (II), the second lifting zone (IV), and the third lifting zone (V) are each provided with one or more rows of the lifting plates (11); the lifting The blank plate (11) is formed by splicing the first steel plate and the second steel plate into the form of a corner plate, wherein the side of the first steel plate is fixed on the inner wall of the inner drum (9), and the second steel plate is fixed with the side of the first steel plate. The second steel plate is located in the inner cavity of the inner drum (9) and is inclined toward the side of the rotation direction of the inner drum (9), so that the sludge inside the inner drum (9) is lifted by the lifting plate (11) during the rotation process. And fall down at a high place; and the folding angles of the lifting plates (11) in the first lifting zone (Ⅱ), the second lifting zone (IV), and the third lifting zone (Ⅴ) decrease in order; the inner drum Each lifting plate (11) in (9) has an inclined slope toward the first sludge discharge port (13), so that the sludge can gradually move towards the first sludge during the rotation of the lifting plate (11). Move one side of the mud discharge port (13);

The sludge disperser (12) is arranged in the dispersion area (III), and the sludge disperser (12) is at least one row of chains, and each row of chains is arranged circumferentially along the inner wall of the inner drum (9). Both ends of the chain are fixed on the inner wall of the inner drum (9), and the distance between the fixed ends is smaller than the length of the chain, so that the chain can crush the internal sludge during the rotation of the inner drum (9);

The first sludge discharge port (13) is arranged at the end of the third lifting zone (V).
The embedded sludge low-temperature drying and granulation device according to claim 9, characterized in that the folding angle of the lifting plate (11) in the first lifting zone (II) is 130-140°, and the second The folding angle of the lifting plate (11) in the lifting zone (IV) is 115-125°, and the folding angle of the lifting plate (11) in the third lifting zone (V) is 100-110°.
The embedded sludge low-temperature drying and granulation device according to claim 9, characterized in that the diameter of the inner drum (9) is 1.5-3.0m, and the axial length is 10-25m; The first steel plate fixed to the inner wall of the inner drum (9) in the lifting plate (11) has a length of 100-120 cm and a width of 19-24 cm, and the first steel plate is installed perpendicular to the inner wall of the inner drum (9), The second steel plate has a length of 100 to 120 cm and a width of 10 to 12 cm.
The inlaid sludge low-temperature drying and granulating device according to claim 9, wherein the diameter of the outer drum is 3.0-5.0m, and the axial length is 10-25m;
The embedded sludge low-temperature drying and granulation device according to claim 9, characterized in that the first lifting zone (II), the second lifting zone (IV), and the third lifting zone (Ⅴ) In ), each row of lifting plates (11) has 16 to 20 lifting plates (11), and each row of lifting plates (11) is arranged at equal angles along the circumferential direction of the inner drum (9).
The inlaid sludge low-temperature drying and granulation device according to claim 9, characterized in that, in the dispersion zone (III), the sludge disperser (12) has 1 to 2 rows of chains, each chain They are arranged at equal angles of 20-25° along the circumferential direction of the inner wall of the inner roller (9).
The inlaid sludge low-temperature drying and granulating device according to claim 9, characterized in that the length of the chain is 115-125 cm, and the two ends of the chain are welded and fixed to the inner wall of the inner drum (9), and the two welded The distance between the points is no more than 90-100 cm.
The inlaid sludge low-temperature drying and granulating device according to claim 9, characterized in that the fixed ends on both sides of the chain also have an inclined slope toward the first sludge discharge port (13) when the chain is installed. The sludge at the bottom of the inner drum (9) can gradually move toward the side of the first sludge discharge port (13) during the rotation process driven by the chain.
A method for low-temperature drying and granulation of sludge using the drying and granulation device according to claim 3, characterized in that it comprises the following steps:

1) Store the sewage treatment plant sludge with a moisture content of 80% or more by weight in the sludge storage bin (20);

2) Through the double screw quantitative sludge feeder (19) installed at the bottom of the sludge storage bin (20), the sludge divided into blocks is uniformly and continuously passed through the sludge inlet (7) by the screw conveyor (18) ) Is fed into the inner drum (9);

3) The flue gas discharged from thermal power plants, cement plants, garbage incineration plants or boilers at a temperature of 120℃～200℃, passes through a multi-tube cyclone dust collector (3) After removing particles ≥PM 10 in the flue gas, use the first induced draft fan (4) It is fed into the inner drum (9) through the first air inlet (5), and the opening degree of the air door is adjusted through the electric gate valve (2) to control the flow of flue gas so that the sludge in the inner drum (9) Synchronous matching of input volume and flue gas input volume;

4) Driven by the driving device, rotate the inner drum (9) clockwise at the set speed without interruption, so that the wet sludge in the inner drum (9) is in direct contact with the hot flue gas, and the sludge is While absorbing heat in the air to evaporate moisture, it absorbs PM 2.5 and PM 10 fine particles, sulfur dioxide and nitrogen oxides in the flue gas, and wraps them in the particles, in the sludge disperser (12) and the lifting plate ( 11) The combined effect of dispersing the sludge into smaller blocks, so that the wet sludge and hot flue gas can be fully contacted with each other in the sludge dispersion and drying equipment for heat exchange reaction;

5) In the inner drum (9), the sludge is pushed to gradually move from the front end to the back end. When the moisture content of the sludge drops below 60%, it enters the outer sludge from the first sludge outlet (13) at the back end. Inside the drum (10);

6) Driven by the driving device, rotate the outer drum (10) and the inner drum (9) clockwise at the set speed without interruption, and use the sludge moving guide plate (14) to push the inner drum (9) down The sludge moves from the rear end to the front end; at the same time, the hot flue gas is sent from the second air inlet (8) into the outer drum (10), in the annular space between the outer drum (10) and the inner drum (9) In the cavity, make the hot flue gas and the sludge continue to directly contact for heat exchange reaction. When the moisture content of the sludge drops below 40% and naturally form sludge particles with a particle size of 2-8 mm, remove them from the bottom of the front end. The output from the second sludge discharge port (29) is sent from the sludge conveyor belt (21) to the sludge product warehouse (22) for cooling. When the sludge particles are cooled to room temperature, the water content drops to <30% and the volume decreases to Less than one-third of the original volume, and 95% of the original calorific value is preserved;

7) After the sludge is dried, the flue gas tail gas is drawn from the air outlet (15) of the inner drum (9) and the outer drum (10) through the second induced draft fan (17), and sent to the dust removal and desulfurization device (16) for processing Dust removal and desulfurization will be discharged from the chimney (23) after treatment.
A method for low-temperature sludge drying and granulation using the drying and granulating device according to claim 10, characterized in that it comprises the following steps:

1) Store the sewage treatment plant sludge with a moisture content of 70% to 80% or more in the total weight mass percentage in the sludge storage bin (20);

2) Through the double screw quantitative sludge feeder (19) installed at the bottom of the sludge storage bin (20), the sludge divided into blocks is uniformly and continuously passed through the sludge inlet (7) by the screw conveyor (18) ) Is fed into the inner drum (9);

3) The flue gas discharged from thermal power plants, cement plants, waste incineration plants or boilers with a temperature of 110℃～200℃, passes through a multi-tube cyclone dust collector (3) After removing particles ≥PM 10 in the flue gas, use the first induced draft fan (4) Send it into the inner drum (9) through the first air inlet (5); or use the hot blast stove (25) to generate hot air, and then adjust the hot air to a suitable temperature through the temperature control device (26), and use the ventilation duct (6) Feed into the inner drum (9) through the first air inlet (5), and adjust the opening degree of the air door through the electric gate valve (2), control the flow of smoke or hot air, so that the inner drum (9) The sludge input volume is synchronized with the flue gas or hot air input volume;

4) Driven by the driving device, rotate the inner drum (9) and the outer drum (10) in a clockwise direction without interruption at the set speed, so that the wet sludge in the inner drum (9) passes through the feeding area ( Ⅰ), the first lifting zone (Ⅱ), the dispersion zone (Ⅲ), the second lifting zone (Ⅳ), the third lifting zone (Ⅴ) and the first sludge discharge outlet (13), wet sludge After entering the first lifting area (II) through the feeding area (Ⅰ), it is driven by the lifting plate (11) to rotate toward the top of the inner drum (9). When the wet sludge rotates to a certain height, the lifting plate (11) The upper part falls off and falls again to the lower lifting plate (11); when the sludge moves to the dispersion area (Ⅲ), the chain of the sludge disperser (12) is continuously tangled and hammered, and is broken Disperse into smaller blocks; then the broken and dispersed small sludge blocks pass through the second lifting zone (IV) and the third lifting zone (V) successively, and gradually become granular, thereby making the wet sludge The hot flue gas can be fully contacted with each other in the sludge dispersion and drying equipment for heat exchange reaction to complete rapid drying; in this process, the wet sludge absorbs heat from the flue gas to evaporate the moisture to complete the preliminary drying At the same time, it absorbs and absorbs PM 2.5 , PM 10 fine particles, sulfur dioxide and nitrogen oxides in the flue gas, and wraps them in the particles;

5) The moisture content of the sludge in the inner drum (9) can be reduced to below 60%, and finally enters the outer drum (10) from the first sludge discharge port (13) at the rear end;

6) Driven by the driving device, rotate the outer drum (10) and the inner drum (9) clockwise without interruption at the set speed, and the sludge movement guide plate (14) in the outer drum (10) pushes the The sludge falling from the inner drum (9) moves from the rear end to the front end; at the same time, the hot flue gas is sent from the second air inlet (8) into the outer drum (10), in the outer drum (10) and the inner drum (9). In the annular cavity between ), the hot flue gas and the sludge continue to directly contact for heat exchange reaction. When the moisture content of the sludge drops below 40%, sludge particles with a particle size of 2-8 mm are naturally formed. It is output from the second sludge discharge port (29) on the bottom of the front end, and sent to the sludge product warehouse (22) by the sludge conveyor belt (21) for cooling. When the sludge particles are cooled to room temperature, the moisture content drops to < 30%, the volume is reduced to less than one-third of the original volume, and 95% of the original calorific value is preserved;

7) After the sludge is dried, the flue gas tail gas is drawn from the air outlet (15) of the inner drum (9) and the outer drum (10) through the second induced draft fan (17), and sent to the dust removal and desulfurization device (16) for processing Dust removal and desulfurization, after treatment, it will be discharged from the chimney (23) up to the standard; or the hot air exhaust after sludge drying will pass through the third induced draft fan (28) from the air outlet (15) of the inner drum (9) and the outer drum (10) ) Is drawn out and sent to a multi-stage dust removal device (27), and after multi-stage treatment, it is discharged from the chimney (23) up to the standard.