Biogas dehydration device for anaerobic fermentation

Abstract

The utility model discloses a biogas dehydration device for anaerobic fermentation, and belongs to the field of biogas dehydration. Comprising a cooling tower bracket, a water collecting tank, a fan, a circulating pump, an upper-layer filler, a lower-layer filler, a spraying pipe, a shutter, a water inlet, a water outlet, an air inlet, an air outlet, an air distribution chamber, an air collecting chamber, a heat exchange pipe, a water outlet, a butterfly valve, a filter screen and the like. Biogas generated by anaerobic fermentation enters the gas distribution chamber through the gas inlet, the gas distribution chamber is provided with a filter screen, the biogas enters the heat exchange pipe after being filtered, cooling water is sprayed to the heat exchange pipe through the spraying pipe to cool and dehydrate the biogas, condensate water flows into the gas distribution chamber and is discharged from the water outlet, and the dehydrated biogas is converged into the gas collection chamber and enters a biogas utilization system. The methane dehydration device is simple in process, less in equipment configuration, simple and convenient to operate, small in occupied area, low in investment cost, capable of being newly built or transformed by using an original cooling tower, free of extra energy consumption, efficient and economical.

Description

Technical Field

[0001] The utility model relates to the field of organic waste treatment, in particular to a biogas dehydration system for anaerobic digestion. Background Art

[0002] Biogas is a combustible gas produced during anaerobic fermentation and is a renewable energy source. Anaerobic fermentation is categorized by fermentation temperature as mesophilic (35±3°C) or thermophilic (55±3°C). Higher fermentation temperatures saturate the biogas with water vapor, reducing its calorific value. Furthermore, biogas also contains hydrogen sulfide, which reacts with water to form an acidic solution that can corrode pipelines. Therefore, it is often necessary to remove moisture from the biogas before use.

[0003] Currently, the main methods for dehydrating biogas include gravity dehydration, condensation dehydration, and cold drying. Gravity dehydration is relatively simple and does not require additional energy, but the dehydration effect is poor. Condensation dehydration uses cooling and heat exchange to condense most of the water vapor in the biogas, which requires additional energy and can remove most of the water. Cold drying dehydration involves freeze-drying the biogas, which has good dehydration effects but high energy consumption.

[0004] This application can be improved on the basis of the cooling tower structure, and different dehydration methods can be adopted according to needs. At the same time, the process is simple, the number of equipment is small, and the operation is easy. Utility Model Content

[0005] In order to solve the defects of existing biogas dehydration equipment, the utility model provides an anaerobic fermentation biogas dehydration device, which is improved on the basis of the cooling tower structure. It has a simple process, a small number of equipment, easy operation, a small footprint, low investment and operating costs, and a good dehydration effect.

[0006] The utility model is mainly realized through the following technical solutions:

[0007] The utility model is a biogas dehydration device for anaerobic fermentation, comprising: a cooling tower support (1), a water collecting tank (3), a fan (4), a circulating pump (5), an upper filler (6), a lower filler (7), a spray pipe (8), a water inlet (12), a water outlet (13), an air inlet (14), an air outlet (15), an air distribution chamber (16), an air collecting chamber (17), a heat exchange pipe (18), a drain outlet (19), and a butterfly valve (20);

[0008] The main structure of the dehydration device comprises a spray pipe (8), an upper filler (6), a heat exchange pipe (18), and a lower filler (7) arranged in sequence. The heat exchange pipe (18) is a modular structure formed by a plurality of parallel pipes. A funnel-shaped air separation chamber (16) is provided at the side end of the heat exchange pipe (18), and an air inlet (14) is provided at a small end of the air separation chamber (16). A funnel-shaped air collection chamber (17) is provided at the other side end of the heat exchange pipe (18), and an air outlet (15) is provided at a small end of the air collection chamber (17). After the biogas to be dehydrated enters from the air inlet (14), it is evenly distributed through the air separation chamber (16) and enters the plurality of pipes in the heat exchange pipe (18) for cooling and dehydration, and then is collected in the air collection chamber (17) and then discharged from the air outlet (15).

[0009] The water collecting tank (3) is located below the lower layer of filler (7); the water collecting tank (3) is installed on the base of the cooling tower bracket (1); the water collecting tank (3) is connected to the spray pipe (8) via a side pipe (22) via a circulation pump (5) and a butterfly valve (20); and a water inlet (12) and a water outlet (13) are respectively provided on the side pipes (22) corresponding to the front and rear of the butterfly valve (20).

[0010] The heat exchange tube is installed at an angle, and the physical position of the heat exchange tube outlet end is higher than the air inlet end, wherein the heat exchange tube is installed at an angle of 3°, so that the condensed water can flow to the air inlet end, and a drain outlet (19) is provided at the bottom of the air chamber so that the condensed water can be discharged (necessary valves, etc. are provided as needed), and at the same time, a filter is installed in the air chamber to filter impurities in the gas.

[0011] A fan (4) for air intake is provided above the heat exchange tube (18); shutters (9) are provided on the sides of the base of the cooling tower support (1) facing upwards, and the shutters (9) are connected to the wall panels (2) with dense walls on all sides. The fan (4), the spray pipe (8), the upper filler (6), and the lower filler (7) are enclosed by the wall panels (2).

[0012] Two parallel heat exchange tubes (18) are arranged between the upper filler (6) and the lower filler (7), one of which serves as a spare and can operate alternately.

[0013] A ladder is hung outside the cooling tower support, and a handrail (11) is provided on the top. The handrail surrounds the fan (4) to ensure the safety of maintenance operations.

[0014] The present application adopts an upper filler (the upper filler makes the circulating water sprayed by the spray pipe more evenly distributed, and is more easily heat-exchanged with the gas from below in the heat exchange tube so that the water evaporates and takes away the heat of the heat exchange tube) and a lower filler (the circulating water heated by the heat exchange tube flows into the lower filler (7) and is evenly spread, flows into the water collection tank after cooling, and continues to serve as a cooling source for the cooling tower for other equipment to cool down). It can also circulate independently to dehydrate the biogas.

[0015] The utility model provides an anaerobic fermentation biogas dehydration device, which has the following beneficial effects:

[0016] A biogas dehydration device for anaerobic fermentation features a simple process, minimal equipment, easy operation, a small footprint, low investment costs, and ease of retrofitting and construction. For example, heat exchange tubes can be integrated into cooling towers, allowing for new construction or retrofitting existing cooling towers without requiring additional energy. This dehydration device efficiently dehydrates biogas, improving its resource utilization. This device effectively dehydrates biogas, resolving issues with existing biogas dehydration technologies. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 The external three-dimensional diagram of the biogas dehydration device provided in the embodiment of the utility model;

[0018] Figure 2 A front view of the specific structure of the biogas dehydration device provided by the embodiment of the utility model;

[0019] Figure 3 A side view of the specific structure of the biogas dehydration device provided in an embodiment of the utility model;

[0020] Figure 4 A top view of the specific structure of the biogas dehydration device provided in an embodiment of the utility model;

[0021] In the figure: 1—cooling tower support; 2—wall panel; 3—water collecting tank; 4—fan; 5—circulating pump; 6—upper filler; 7—lower filler; 8—spray pipe; 9—louver; 10—ladder; 11—railing; 12—water outlet; 13—water inlet; 14—air inlet; 15—air outlet; 16—air distribution chamber; 17—air collecting chamber; 18—heat exchange tube; 19—drain outlet; 20—butterfly valve; 21—filter; 22—side pipe. DETAILED DESCRIPTION

[0022] The technical solutions in the embodiments of the present invention are clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. The contents not described in detail in the present invention belong to the prior art known to professional and technical personnel in this field.

[0023] As shown in the figure, the embodiment of the utility model is a biogas dehydration device for anaerobic fermentation, which can solve the problems of high energy consumption and poor dehydration effect of the existing biogas dehydration process.

[0024] This device utilizes a cooling tower to circulate and cool biogas for dehydration. Two sets of heat exchange piping are provided, one for use and one for backup. The biogas pipeline is divided into two paths by a tee before the air inlet, each connected to the two air inlets 14 with flanges and fitted with valves. During normal operation, one path is open and the other closed, alternating between them. When one heat exchange piping path requires maintenance, the valve is switched to use the other path, ensuring continuous operation.

[0025] Biogas Path: Biogas enters the gas distribution chamber 16 through the air inlet 14. A filter 21 is installed inside the gas distribution chamber 16 to remove impurities in the biogas. The biogas in the gas distribution chamber 16 then flows evenly into the heat exchange tubes 18. Cooling water sprays the heat exchange tubes 18, while hot biogas flows inside. Heat exchange occurs between the two phases, and the water vapor in the biogas condenses into liquid water. This water vapor flows through the heat exchange tubes 18 into the gas distribution chamber 16 and is discharged through the drain 19. The dehydrated biogas then flows into the gas collection chamber 17 and enters the biogas utilization system.

[0026] External cooling path. When used as a cooling tower, the butterfly valve 20 between the water outlet 12 and the water inlet 13 is in a closed state. The cooling circulating water in the water collection tank 3 is transported from the water outlet 12 to other heat exchange equipment through the circulating pump 5 (not shown in the drawings of this application, and used as cooling tower circulating water to cool other heat exchange equipment), and the circulating water is heated. After heating, the circulating water enters the spray pipe 8 through the water inlet 13 and is evenly sprayed on the upper layer of filler 6, so that the circulating water is evenly distributed and evenly sprayed on the surface of the heat exchange tube 18. The fan 4 sucks the cold air in from the louver 9 and enters the lower filler layer 7, and then performs heat exchange on the water film on the surface of the upper filler 6 (the principle of heat exchange is that the wind takes away heat). The generated water vapor is discharged from the top. At the same time, the circulating water that has been heated on the surface of the heat exchange tube 18 enters the lower filler 7 again for heat exchange, and flows into the water collection tank 3 after cooling.

[0027] Or an external cooling path, using its own separate circulation to dehydrate the biogas, disconnecting from the water outlet 12 and the water inlet 13, opening the butterfly valve 20, and using the circulating pump 5 to directly circulate water for cooling and dehydrating the biogas.

[0028] The biogas dehydration device basically does not require additional power equipment and does not require additional energy consumption.

[0029] In summary, the biogas dehydration device of the present invention has simple equipment configuration, small floor space, and low equipment investment and operating costs.

[0030] The above description is only a description of the present invention and is not intended to limit the scope of the present invention. Any modification, replacement, and improvement within the concept of the present invention shall be included in the scope of protection of the present invention.

Claims

1. A biogas dehydration device for anaerobic fermentation, characterized in that: include: Cooling tower support (1), water collecting tank (3), fan (4), circulation pump (5), upper layer filler (6), lower layer filler (7), spray pipe (8), water inlet (12), water outlet (13), air inlet (14), air outlet (15), air distribution chamber (16), air collecting chamber (17), heat exchange pipe (18), drain outlet (19), butterfly valve (20); The main structure of the dehydration device comprises a spray pipe (8), an upper filler (6), a heat exchange pipe (18), and a lower filler (7) arranged in sequence. The heat exchange pipe (18) is a modular structure formed by a plurality of parallel pipes. A funnel-shaped air separation chamber (16) is provided at the side end of the heat exchange pipe (18), and an air inlet (14) is provided at a small end of the air separation chamber (16). A funnel-shaped air collection chamber (17) is provided at the other side end of the heat exchange pipe (18), and an air outlet (15) is provided at a small end of the air collection chamber (17). After the biogas to be dehydrated enters from the air inlet (14), it is evenly distributed through the air separation chamber (16) and enters the plurality of pipes in the heat exchange pipe (18) for cooling and dehydration, and then is collected in the air collection chamber (17) and then discharged from the air outlet (15). The water collecting tank (3) is located below the lower layer of filler (7); the water collecting tank (3) is installed on the base of the cooling tower support (1); the water collecting tank (3) is connected to the spray pipe (8) via a side pipe (22) via a circulation pump (5) and a butterfly valve (20); a water inlet (12) and a water outlet (13) are respectively provided on the side pipes (22) corresponding to the front and rear of the butterfly valve (20); The heat exchange tube outlet end is physically higher than the air inlet end so that condensed water can flow through the air inlet end. A drain port (19) is provided at the bottom of the air chamber so that the condensed water can be discharged. At the same time, a filter is installed in the air chamber to filter impurities in the gas. A fan (4) for air intake is provided above the heat exchange tube (18); shutters (9) are provided on the sides of the base of the cooling tower support (1) facing upwards, and the shutters (9) are connected to the wall panels (2) with dense walls on all sides. The fan (4), the spray pipe (8), the upper filler (6), and the lower filler (7) are enclosed by the wall panels (2).

2. The biogas dehydration device for anaerobic fermentation according to claim 1, characterized in that: The heat exchange tube installation angle is 3°.

3. The biogas dehydration device for anaerobic fermentation according to claim 1, characterized in that: Two parallel heat exchange tubes (18) are arranged between the upper filler (6) and the lower filler (7), one of which serves as a spare and can operate alternately.

4. The biogas dehydration device for anaerobic fermentation according to claim 1, characterized in that: A ladder is hung outside the cooling tower support, and a handrail (11) is provided on the top, and the handrail surrounds the fan (4).

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