CN113149186A

CN113149186A - Aerobic ecological moving bed for biological drying

Info

Publication number: CN113149186A
Application number: CN202110007122.3A
Authority: CN
Inventors: 杨英英; 陈传好
Original assignee: Zhuzhou Times New Material Technology Co Ltd
Current assignee: Zhuzhou Times New Material Technology Co Ltd
Priority date: 2021-01-05
Filing date: 2021-01-05
Publication date: 2021-07-23

Abstract

The invention provides an aerobic ecological moving bed for biological drying, which comprises a tank body and a feeding device arranged at the upper part of the tank body, wherein the feeding device conveys sludge into the tank body; the aeration device is arranged in the tank body, is arranged below the feeding device and has a height lower than the stacking height of the sludge; wherein, the aeration device conveys the outside air into the tank body, the sludge carries out the biological drying reaction under the action of oxygen, and the aeration device also conveys the generated water vapor to the outside of the tank body.

Description

Aerobic ecological moving bed for biological drying

Technical Field

The invention relates to an aerobic ecological moving bed for biological drying, belonging to the field of sludge treatment.

Background

Along with the continuous improvement of the sewage treatment rate and the sewage treatment degree in China, the urban sludge yield also increases year by year. The municipal sludge is mainly aerobic microorganisms, and simultaneously comprises solid matters such as silt, fibers, animal and plant residues and the like mixed in sewage, and adsorbed organic matters, heavy metals, germs, insect eggs and the like. If a large amount of municipal sludge is not properly disposed, serious secondary pollution will be caused.

At present, the sludge treatment method mainly comprises landfill, land utilization, incineration and the like. Because the water content of the municipal sludge is usually higher, the water content of the municipal sludge is still about 80 percent after concentration and dehydration treatment, and the municipal sludge has the characteristics of large volume, unfavorable transportation, unstable property and the like. Direct landfill occupies a large amount of land, and leachate pollutes underground water; land utilization is greatly limited due to large transportation volume, difficult dispersion and easy pollution to underground water; direct incineration also has a low calorific value due to low solid content, and cannot maintain effective spontaneous combustion, so that a large amount of auxiliary fuel is consumed, and the disposal cost is obviously increased. Therefore, the key to solve many problems encountered in the sludge treatment process at present is to carry out drying treatment on the municipal sludge and reduce the water content of the sludge.

The traditional sludge drying method adopts a sludge drying bed form, sludge is accumulated in an outdoor drying bed, and the sludge is dried under the action of natural ventilation and gravity. The modern drying process is mainly heat drying, namely a process for evaporating water in sludge by an external heating source, and has the advantages of small floor area, obvious reduction, flexible product application and the like. However, the heat drying process has many problems, mainly including high investment and operation cost, high equipment operation energy consumption, and dust explosion potential safety hazard, and is difficult to be popularized and applied in large scale in China. Therefore, the development of a more economical and energy-saving drying technology becomes an urgent need for municipal sludge treatment in China.

Biodesiccation was first proposed by jewell et al, Connell university, USA, in 1984 when studying the operational parameters of cow dung bio-desiccation, sometimes called bio-desiccation, biostabilization. The biological drying is a treatment process which adopts a process control means, utilizes the bioenergy generated by the degradation of organic matters in the high-temperature aerobic fermentation process of microorganisms and is matched with forced ventilation to promote the evaporation and removal of water, thereby realizing the rapid drying.

At present, biological drying processes at home and abroad are various in form, and common biological drying technologies comprise strip-stack type fermentation drying and fermentation tank (bin) type fermentation drying. The strip pile type fermentation is generally open-air fermentation, and the raw material mixture is generally piled into a strip pile, the section of the strip pile can be trapezoid or triangular, and the strip pile type fermentation method is a common aerobic fermentation method. The strip stacks are too large, an anaerobic zone is easily generated in the center, and odor is generated when the stacks are turned; the stack is too small, dissipating heat quickly, and it is difficult to ensure killing of pathogens and weed seeds. Fermentation tank type fermentation is carried out in a factory building or a tunnel bin and can be divided into a sunlight shed fermentation tank and a tunnel type fermentation bin, and the existing common fermentation process generally has uneven mass transfer and long fermentation time; the system occupies large area; the odor is big, and the collection and the disposal are difficult.

Disclosure of Invention

Aiming at the technical problems in the prior art, the invention provides an aerobic ecological moving bed for biological drying, which adopts a closed design, has no odor overflow, does not need to increase the cost for the second time and is provided with an expensive deodorization system, can be directly arranged in a plant area for centralized treatment of sludge, and the generated heat carries out self-drying in the process of treating the sludge.

The invention provides an aerobic ecological moving bed for biological drying, which comprises:

a tank body which is provided with a plurality of tanks,

the feeding device is arranged at the upper part of the tank body and is used for conveying sludge into the tank body;

the aeration device is arranged in the tank body, is arranged below the feeding device and has a height lower than the stacking height of the sludge;

wherein, the aeration device conveys the outside air into the tank body, the sludge carries out the biological drying reaction under the action of oxygen, and the aeration device also conveys the generated water vapor to the outside of the tank body.

The invention is further improved in that the aeration device comprises a plurality of vertically arranged exhaust pipes and air suction pipes; the exhaust pipe is provided with a plurality of exhaust holes for exhausting outside air into the tank body; the air suction pipe is provided with a plurality of air suction holes for discharging the gas in the tank body.

The invention is further improved in that the aeration device also comprises circular exhaust manifolds and circular suction manifolds with different diameters, the exhaust pipes are uniformly arranged at the lower ends of the exhaust manifolds, and the suction pipes are uniformly arranged at the lower ends of the suction manifolds;

wherein the exhaust manifold and the intake manifold are coaxially arranged and are spaced apart from each other.

The invention is further improved in that the exhaust manifold is connected with an aeration fan outside the tank body through a first air pipe, and the aeration fan transmits air to the exhaust manifold through the first air pipe and discharges the air into the tank body through the exhaust pipe.

The invention is further improved in that the air suction manifold is connected with an induced draft fan outside the tank body through a second air pipe, and the induced draft fan pumps out air in the tank body through the second air pipe.

The invention is further improved in that an air purification device is arranged at the output end of the induced draft fan.

A further development of the invention is that the first gas pipe and the second gas pipe are heat exchanged by means of a heat exchanger.

The invention is further improved in that a discharging device is arranged at the bottom of the tank body, and the sludge is discharged out of the tank body through the discharging device after being dried.

A further improvement of the present invention is that the distance between the height of the sludge heap and the height of the aeration device is proportional to the distance between the exhaust pipe and the suction pipe.

The invention is further improved in that a feed inlet is arranged at one end of the feeding device positioned outside the tank body, a distributing device is arranged at one end of the feeding device positioned inside the tank body, and the distributing device is used for uniformly accumulating the materials conveyed in the feeding device in the tank body.

Compared with the prior art, the invention has the advantages that:

the invention relates to an aerobic ecological moving bed for biological drying, which is an aerobic fermentation technology with high efficiency, low consumption, environmental protection and small occupied area. And the drying and weight reducing capacity is strong, the water content of the dry sludge is less than or equal to 20-50%, the drying and weight reducing capacity can be adjusted, the reduction amount is more than 80%, and the technical bottleneck that the water content of the dry sludge is high and the weight reducing capacity is weak in the traditional drying mode is overcome.

The aerobic ecological moving bed for biological drying does not need an external heating source, does not need additional auxiliary materials and does not need to add extra strains, a large amount of biological energy released by the growth and the propagation of microorganisms in sludge is used for drying, only sludge conveying and an aeration fan need to consume electricity, and the operation cost is low. Realizes medium temperature composting at 55-80 ℃ for more than 5 days, meets the composting requirement, and can be used as a fertilizer for landscaping. The vertical gravity flow design is adopted, pile turning is not needed, the vertical design occupies a very small area which is only 10% of the area occupied by the conventional compost;

the invention carries out self-drying by utilizing the heat generated in the metabolism process of the microorganisms, hot gas generated in the drying process enters a heat exchanger through a draught fan to preheat inlet air, thereby realizing heat energy circulation and ensuring that the microorganisms are at the optimal reaction temperature; the aeration adopts a transverse aeration mode, the wind resistance is small, and the energy consumption is low.

Meanwhile, no odor is discharged, and no deodorization is needed. The whole equipment system adopts a closed design, is free of odor overflow, does not need secondary cost increase to install an expensive deodorization system, can be directly installed in a plant area, carries out sludge centralized treatment, and can directly discharge condensed water without secondary treatment. The design of a closed system is adopted, so that the heat pump can be operated efficiently in winter without heat loss, and the heat pump can be utilized in hundred percent without limitation of seasons.

The tank body is totally closed, the tank body works at the medium temperature of 55-80 ℃, the dust concentration is less than 60g/m3, the particle temperature is less than 70 ℃, the potential hazards of dust raising and explosion are avoided, the discharge temperature is less than 50 ℃, secondary cooling is not needed, the tank body can be directly stored, and the safety is high.

Drawings

Preferred embodiments of the present invention will be described in detail below with reference to the attached drawing figures, wherein:

FIG. 1 is a schematic structural diagram of an aerobic ecological moving bed for bio-drying according to an embodiment of the present invention;

fig. 2 is a schematic structural view of an aeration apparatus according to an embodiment of the present invention.

In the drawings, like parts are provided with like reference numerals. The figures are not drawn to scale.

The meaning of the reference symbols in the drawings is as follows: 1. the device comprises a tank body, 2, an aeration device, 11, a feeding device, 12, a distributing device, 13, a discharging device, 20, an exhaust pipe, 21, an air suction pipe, 22, an exhaust manifold, 23, an air suction manifold, 24, a first air pipe, 25, a second air pipe, 26, an aeration fan, 27, an induced draft fan, 28, an air purification device, 29 and a heat exchanger.

Detailed Description

In order to make the technical solutions and advantages of the present invention more apparent, exemplary embodiments of the present invention are described in further detail below with reference to the accompanying drawings. It is clear that the described embodiments are only a part of the embodiments of the invention, and not an exhaustive list of all embodiments. And the embodiments and features of the embodiments may be combined with each other without conflict.

Fig. 1 schematically shows an aerobic ecological moving bed for bio-drying according to one embodiment of the present invention, comprising a tank body 1. The tank body 1 is a closed space, the upper part of the tank body 1 is provided with a feeding device 11, and the feeding device 11 conveys sludge into the tank body 1. An aeration device 2 is arranged in the tank body 1, and the aeration device 2 can convey air into the tank body 1. The aeration device 2 is arranged below the feeding device 11, and the height of the aeration device 2 is lower than the height of sludge stacking. Wherein, the aeration device 2 conveys external air into the tank body 1, sludge is subjected to biological drying reaction under the action of oxygen, and the aeration device 2 also conveys generated water vapor to the outside of the tank body 1.

When the aerobic ecological moving bed for bio-drying according to the embodiment is used, sludge is conveyed into the tank body 1 through the feeding device 11 and is accumulated in the tank body 1. Air is input into the accumulated sludge through the aeration device 2, and self-drying is carried out by utilizing heat generated in the microbial metabolism process.

In one embodiment, the aeration device 2 comprises a plurality of exhaust pipes 20 and air suction pipes 21, wherein the exhaust pipes 20 can exhaust air into the tank 1, and the air suction pipes 21 can suck the air in the tank 1. The exhaust pipe 20 and the suction pipe 21 are both disposed in a vertical direction. The exhaust pipe 20 is provided with a plurality of exhaust holes which are uniformly arranged in the vertical direction of the exhaust pipe 20, the air suction pipe 21 is provided with a plurality of air suction holes, and the air suction holes are uniformly arranged in the vertical direction of the air suction pipe 21.

In the aerobic ecological moving bed for biological drying according to the embodiment, the exhaust holes and the air suction holes on the exhaust pipe 20 and the air suction pipe 21 are transversely arranged, and the aeration adopts a transverse aeration mode, so that the wind resistance is small, and the energy consumption is low.

In one embodiment, as shown in fig. 1 and 2, the aeration apparatus 2 further comprises an exhaust manifold 22 and an intake manifold 23, and the exhaust manifold 22 and the intake manifold 23 are both circular in structure and horizontally disposed. The upper end of the exhaust pipe 20 is connected to the lower end of the exhaust manifold 22, and the upper end of the intake pipe 21 is connected to the lower end of the intake manifold 23. In this embodiment, the exhaust manifolds 22 and the suction manifolds 23 have different diameters, and the exhaust manifolds 22 and the suction manifolds 23 are coaxially disposed (as shown in fig. 2), and the distances between the adjacent exhaust manifolds 22 and the adjacent suction manifolds 23 are close to each other, so that air can be uniformly introduced into the sludge.

In one embodiment, the exhaust manifold 22 is connected to an aerator fan 26 outside the tank 1 via a first air pipe 24, and the aerator fan 26 pumps outside air to the exhaust manifold 22 via the first air pipe 24 and discharges the air into the tank 1 via the exhaust pipe 20 at the exhaust manifold 22.

In one embodiment, the air suction header 23 is connected with an induced draft fan 27 outside the tank body 1 through a second air pipe 25, and the induced draft fan 27 extracts air in the tank body 1 through the second air pipe 25. During operation, the aeration fan 26 pumps external air to the exhaust manifold 22 through the first air pipe 24, the air in the exhaust manifold 22 flows uniformly into each exhaust pipe 20, and the exhaust pipes 20 discharge the air into the tank 1 through the exhaust holes. Air is mixed with sludge in the tank body 1 to dry the sludge, water vapor generated in the drying process enters the air suction pipe 21 through the air suction hole and enters the air suction manifold 23 along the air suction pipe 21, and the air in the air suction manifold 23 is discharged under the action of the induced draft fan 27.

In one embodiment, the output end of the induced draft fan 27 is provided with an air purification device. The gas discharged from the tank body 1 is purified by the air purification device 28 and then discharged to the atmosphere, so that impurities or harmful gas in the sludge are prevented from entering the atmosphere and polluting the environment.

In one embodiment, a heat exchanger 29 is disposed outside the tank 1, two pipelines of the heat exchanger 29 are respectively provided with a first air pipe 24 and a second air pipe 25, and the first air pipe 24 and the second air pipe 25 exchange heat through the heat exchanger 29. The steam generated in the drying process enters the heat exchanger 29 through the action of the draught fan 27 to preheat the inlet air of the system, so that the heat energy circulation is realized, the microorganisms are at the optimal reaction temperature, and the condensed water is discharged.

In one embodiment, the bottom of the tank body 1 is provided with a discharging device 13, and the sludge is dried and then discharged out of the tank body 1 through the discharging device 13.

When the aerobic ecological moving bed for biological drying according to the embodiment is used, the feeding device 11 conveys sludge to the upper end of the feeding device 11, the sludge is uniformly distributed in the biological drying device through the feeding device 11, the sludge stacking height is higher than the certain height of the aeration device 2, the height can be determined according to the distance between the air inlet pipe and the air outlet pipe of the aeration pipeline, and the sludge stacking height and the air inlet pipe and the air outlet pipe are in direct proportion according to a certain coefficient. The aeration fan 26 and the aeration pipe are used for forcibly oxygenating the ecological moving bed, water vapor generated in the drying process enters the heat exchanger 29 under the action of the draught fan 27 to preheat inlet air of the system, heat energy circulation is realized, and condensed water is directly discharged. The sludge slowly moves downwards under the action of the self gravity, and the dried sludge is discharged out of the reactor from the bottom.

In one embodiment, a feeding hole is arranged at one end of the feeding device 11 positioned outside the tank body 1, a distributing device 12 is arranged at one end of the feeding device 11 positioned inside the tank body 1, and the distributing device 12 is used for uniformly accumulating the materials conveyed in the feeding device 11 in the tank body 1.

While preferred embodiments of the present invention have been described, additional variations and modifications in those embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. Therefore, the appended claims are intended to be construed to include preferred embodiments and all such changes and/or modifications as fall within the scope of the invention, and all such changes and/or modifications as are made to the embodiments of the present invention are intended to be covered by the scope of the invention.

Claims

1. An aerobic ecological moving bed for biological drying, which is characterized by comprising:

a tank body (1),

the feeding device (11) is arranged at the upper part of the tank body (1), and the feeding device (11) conveys sludge into the tank body (1);

the aeration device (2) is arranged in the tank body (1), the aeration device (2) is arranged below the feeding device (11), and the height of the aeration device (2) is lower than the stacking height of sludge;

wherein, the aeration device (2) conveys external air into the tank body (1), sludge is subjected to biological drying reaction under the action of oxygen, and the aeration device (2) also conveys generated water vapor to the outside of the tank body (1).

2. An aerobic ecological moving bed for bio-drying according to claim 1, wherein the aeration means (2) comprises a number of vertically arranged gas exhaust pipes (20) and gas suction pipes (21); a plurality of exhaust holes are formed in the exhaust pipe (20) and exhaust external air into the tank body (1); the air suction pipe (21) is provided with a plurality of air suction holes for discharging the air in the tank body (1).

3. An aerobic ecological moving bed for bio-drying according to claim 2, wherein the aeration device (2) further comprises circular exhaust manifolds (22) and suction manifolds (23) of different diameters, the exhaust pipes (20) are evenly arranged at the lower end of the exhaust manifolds (22), and the suction pipes (21) are evenly arranged at the lower end of the suction manifolds (23);

wherein the exhaust manifold (22) and the intake manifold (23) are coaxially arranged, and the exhaust manifold (22) and the intake manifold (23) are arranged at intervals.

4. An aerobic ecological moving bed for bio-drying according to claim 3, wherein the exhaust manifold (22) is connected to an aeration fan (26) outside the tank (1) via a first air pipe (24), the aeration fan (26) transferring air to the exhaust manifold (22) via the first air pipe (24) and discharging into the tank (1) via the exhaust pipe (20).

5. The aerobic ecological moving bed for bio-drying according to claim 4, wherein the air suction manifold (23) is connected with an induced draft fan (27) outside the tank body (1) through a second air pipe (25), and the induced draft fan (27) pumps out the air in the tank body (1) through the second air pipe (25).

6. An aerobic ecological moving bed for bio-drying according to claim 5, wherein the output of the induced draft fan (27) is provided with an air cleaning device (28).

7. An aerobic ecological moving bed for bio-drying according to claim 6, wherein the first gas pipe (24) and the second gas pipe (25) are heat exchanged by a heat exchanger (29).

8. An aerobic ecological moving bed for bio-drying according to any of the claims 4 to 6, wherein the bottom of the tank (1) is provided with a discharging device (13), and the sludge is dried and discharged out of the tank (1) through the discharging device (13).

9. An aerobic ecological moving bed for bio-drying according to claim 8, wherein the distance between the height of the sludge heap and the height of the aeration device (2) is proportional to the distance between the exhaust pipe (20) and the suction pipe (21).

10. An aerobic ecological moving bed for bio-drying according to claim 9, wherein the end of the feeding device (11) located outside the tank (1) is provided with a feeding port, the end located inside the tank (1) is provided with a distributing device (12), and the distributing device (12) is used for uniformly accumulating the materials conveyed in the feeding device (11) in the tank (1).