Recycling and reusing system for associated biogas of sewage station

Abstract

The utility model discloses a sewage station associated biogas recycling system, which relates to the technical field of biogas treatment and comprises a sewage tank, an anaerobic reaction device, a torch, a water-gas separation device, a desulfurization device and a steam generator. The bottom of the torch is provided with a third pipeline, one end of the third pipeline is provided with a first biogas storage container, the first biogas storage container is connected with the anaerobic reaction device, and the other end of the third pipeline is connected with the water-gas separation device. According to the utility model, the first biogas storage container and the second biogas storage container are arranged and are matched with the Roots blower in the air inducing mechanism to pressurize, so that biogas generated in the system can be stored in the first biogas storage container or the second biogas storage container and can be released when the biogas demand is increased; the system is used for maintaining the balance of gas in the system so as to cope with the risk caused by non-uniform anaerobic gas production, a stable gas source is supplied to rear-end equipment, and the biogas recovery efficiency is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of biogas treatment, in particular to a system for recovering and reusing biogas associated with a sewage station. Background Art

[0002] After industrial wastewater or domestic sewage is treated at the sewage treatment plant, it enters the anaerobic biological treatment stage, where the metabolic characteristics of anaerobic microorganisms are utilized to degrade organic matter in sewage without providing exogenous energy, using reduced organic matter as hydrogen acceptors to produce gases such as methane and carbon dioxide. Among them, methane is the main component of biogas and has a high calorific value. It can be used as a clean energy in power generation, heating and other fields.

[0003] At present, in the process of sewage treatment, the biogas produced is mostly discharged by direct combustion, which not only leads to a large amount of clean energy being wasted, but also pollutants such as H2S (hydrogen sulfide) produced during anaerobic reaction and SO2 (sulfur dioxide) produced during combustion will cause pollution to the atmosphere.

[0004] In order to overcome the environmental impact of biogas combustion and emission generated by existing sewage treatment, some factories are equipped with biogas recovery equipment. However, since the biogas associated with sewage treatment plants has an off-season production period, the biogas production and consumption are prone to imbalance. In addition, the biogas pressure at the water seal is low, which leads to unstable biogas supply during actual operation of the equipment, resulting in low efficiency in biogas recovery and utilization. Utility Model Content

[0005] The technical problem to be solved by the utility model is to provide a sewage station associated biogas recovery and reuse system in view of the current status of the prior art.

[0006] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0007] A system for recovering and reusing associated biogas in a sewage station comprises a sewage pool, an anaerobic reaction device, a flare, a water-gas separation device, a desulfurization device, and a steam generator; a third pipeline is arranged at the bottom of the flare, a first biogas storage container is installed at one end of the third pipeline, the first biogas storage container is connected to the anaerobic reaction device, the other end of the third pipeline is connected to the water-gas separation device, a seventh pipeline is installed outside the water-gas separation device, a second biogas storage container is arranged at the other end of the seventh pipeline, a fifth pipeline is connected outside the second biogas storage container, the other end of the fifth pipeline is connected to the desulfurization device, an eighth pipeline is installed on the desulfurization device, and an air induced draft mechanism is arranged at the other end of the eighth pipeline.

[0008] Preferably, the anaerobic reaction device comprises an anaerobic tank, a first pipe and a second pipe, the anaerobic tank is connected to the sewage pool through the first pipe, and the anaerobic tank is connected to the first biogas storage container through the second pipe.

[0009] Preferably, a valve is provided at the connection between the third pipeline and the flare.

[0010] Preferably, the water-gas separation device comprises a dry-wet separator, and the dry-wet separator is distributed in two groups.

[0011] Preferably, a safety valve and a pressure gauge are installed on the outside of the dry-wet separator, and a precision filter element is arranged inside the dry-wet separator.

[0012] Preferably, the desulfurization device comprises desulfurization towers, and the desulfurization towers are distributed in two groups.

[0013] Preferably, a fourth pipeline is installed outside the desulfurization tower, a dosing pump is provided at the other end of the fourth pipeline, and a dosing tank is installed at one end of the dosing pump.

[0014] Preferably, the air induction mechanism comprises a Roots blower, a negative pressure sensor is provided at the inlet of the Roots blower, and a pressure transmitter is installed at the outlet of the Roots blower.

[0015] Preferably, the outlet of the Roots blower is connected to a sixth pipeline, and the steam generator is connected to the Roots blower through the sixth pipeline.

[0016] In summary, due to the adoption of the above technical solution, the beneficial effects of the utility model are:

[0017] 1. In the utility model, by setting a first biogas storage container and a second biogas storage container and cooperating with the Roots blower in the induced draft mechanism for pressurization, the biogas generated in the system can be stored in the first biogas storage container or the second biogas storage container, and can be released when the demand for biogas increases, so as to maintain the balance of gas in the system, to cope with the risks caused by uneven anaerobic gas production, to supply a stable gas source for the back-end equipment, and to help improve the biogas recovery efficiency.

[0018] 2. In the utility model, by providing the first biogas storage container and the second biogas storage container, when any device of the desulfurization tower, the dry-wet separator, and the steam generator in the system fails or needs maintenance, the first biogas storage container or the second biogas storage container can be used to buffer the biogas retained in the system, thereby reducing the use of traditional combustion and emission methods to treat the remaining biogas, which is beneficial to reducing the impact of traditional combustion and emission methods on the environment, saving energy for society, and providing economic value for enterprises. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a process flow chart of a sewage station associated biogas recovery and reuse system of the utility model;

[0020] Figure 2 The utility model is a partial process flow chart of a sewage station associated biogas recovery and reuse system.

[0021] Legend:

[0022] 1. Sewage pool; 2. Anaerobic reaction device; 21. First pipeline; 22. Anaerobic tank; 23. Second pipeline; 3. First biogas storage container; 4. Flare; 41. Third pipeline; 5. Water-gas separation device; 51. Dry-wet separator; 52. Safety valve; 53. Pressure gauge; 54. Precision filter element; 6. Desulfurization device; 61. Desulfurization tower; 62. Dosing tank; 63. Dosing pump; 64. Fourth pipeline; 7. Second biogas storage container; 71. Fifth pipeline; 8. Induced draft mechanism; 81. Roots blower; 82. Sixth pipeline; 83. Pressure transmitter; 84. Negative pressure sensor; 9. Steam generator; 10. Seventh pipeline; 11. Eighth pipeline. DETAILED DESCRIPTION

[0023] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0024] Please refer to Figure 1-Figure 2The utility model provides a system for recovering and reusing associated biogas from a sewage station, comprising a sewage pool 1, an anaerobic reaction device 2, a flare 4, a water-gas separation device 5, a desulfurization device 6, and a steam generator 9; a third pipeline 41 is arranged at the bottom of the flare 4, and the flare 4 adopts a biogas internal combustion flare 4 (the composition and working process of the flare 4 are existing mature technologies, so they are not described in detail). By providing the flare 4, when the steam generator 9 stops operating or the biogas production capacity is in excess, and the gas storage capacity of the first biogas storage container 3 and the second biogas storage container 7 reaches a set threshold, the flare 4 can be used to burn off the excess biogas, and emergency treatment of the biogas generated in the system is carried out. A first biogas storage container 3 is installed at one end of the third pipeline 41, and the first biogas storage container 3 adopts a biogas buffer tank for caching biogas. By providing the first biogas storage container 3, it is convenient to cache the biogas generated in the system, which is conducive to maximizing the recovery and utilization of biogas and reducing the use of traditional combustion and emission methods to treat the remaining biogas in the system. The container 3 is connected to the anaerobic reaction device 2, so that the sewage in the sewage pool 1 is fermented through the anaerobic tank 22 in the anaerobic reaction device 2 to produce biogas (the composition and working principle of the anaerobic tank 22 are existing mature technologies, so they will not be described in detail). The other end of the third pipe 41 is connected to the water-gas separation device 5, and a seventh pipe 10 is installed outside the water-gas separation device 5. The other end of the seventh pipe 10 is provided with a second biogas storage container 7. The second biogas storage container 7 adopts a dual-mode gas storage cabinet (the composition and working principle of the dual-mode gas storage cabinet are existing mature technologies, so they will not be described in detail). It is used to store biogas. When there is excess biogas in the system, the excess biogas is stored through the dual-mode gas storage cabinet and released when the demand for biogas increases to maintain the gas balance in the system to cope with the risks caused by uneven anaerobic gas production. The outside of the second biogas storage container 7 is connected to a fifth pipe 71, and the other end of the fifth pipe 71 is connected to the desulfurization device 6. The desulfurization device 6 is installed with an eighth pipe 11, and the other end of the eighth pipe 11 is provided with an induced draft mechanism 8.

[0025] like Figure 1 As shown, in this embodiment, the anaerobic reaction device 2 includes an anaerobic tank 22, a first pipe 21 and a second pipe 23. The anaerobic tank 22 is connected to the sewage pool 1 through the first pipe 21, and the anaerobic tank 22 is connected to the first biogas storage container 3 through the second pipe 23, so that the sewage in the sewage pool 1 enters the anaerobic tank 22 from the first pipe 21, and generates biogas after anaerobic reaction, and the biogas then enters the first biogas storage container 3 through the second pipe 23.

[0026] like Figure 2As shown, in this embodiment, a valve is provided at the connection between the third pipeline 41 and the flare 4 (the valve is not marked in the attached figure), and the flare 4 is used for emergency disposal. When the biogas recovery and reuse system operates normally, the valve on the third pipeline 41 is in a closed state, and the flare 4 is not enabled; when the steam generator 9 stops operating or the biogas production capacity is in excess, and the gas storage capacity of the first biogas storage container 3 and the second biogas storage container 7 reaches the set threshold, the valve is in an open state, the flare 4 is started, and the excess biogas is burned by the flare 4, so as to perform emergency disposal on the biogas in the system.

[0027] like Figure 2 As shown, in this embodiment, the water-gas separation device 5 includes a dry-wet separator 51, and the dry-wet separator 51 is distributed in two groups.

[0028] In this embodiment, a safety valve 52 and a pressure gauge 53 are installed on the outside of the dry-wet separator 51, and a precision filter element 54 is arranged inside the dry-wet separator 51. Since the water content of the biogas passed through the water seal of the anaerobic tank 22 is relatively large, the biogas passes through the precision filter element 54 in the dry-wet separator 51 to complete the water-gas separation operation, which is used to reduce the water gas in the biogas. At the same time, the content of hydrogen sulfide in the biogas is reduced, which is beneficial to reduce the corrosion intensity of the biogas to subsequent equipment and pipelines.

[0029] like Figure 2 As shown, in this embodiment, the desulfurization device 6 includes a desulfurization tower 61, and the desulfurization tower 61 is distributed in two groups.

[0030] In this embodiment, a fourth pipeline 64 is installed on the outside of the desulfurization tower 61, and a dosing pump 63 is provided at the other end of the fourth pipeline 64. A dosing tank 62 is installed at one end of the dosing pump 63. The desulfurization agent injected into the dosing tank 62 can come from an external device, and the dosing pump 63 is used to pump the desulfurization agent in the dosing tank 62 into the desulfurization tower 61 to desulfurize the biogas in the system, thereby preventing the hydrogen sulfide in the biogas from corroding the steam generator 9, which is beneficial to improve the service life of the steam generator 9.

[0031] like Figure 1 As shown, in this embodiment, the air induced mechanism 8 includes a Roots blower 81, and a negative pressure sensor 84 is provided at the inlet of the Roots blower 81. The negative pressure sensor 84 is used to prevent the equipment from being vacuumed. A pressure transmitter 83 is installed at the outlet of the Roots blower 81. The Roots blower 81 is of explosion-proof type, and the pressure transmitter 83 provided at the outlet is used to adjust the frequency conversion frequency of the Roots blower 81.

[0032] In this embodiment, the outlet of the Roots blower 81 is connected to the sixth pipeline 82, and the steam generator 9 is connected to the Roots blower 81 through the sixth pipeline 82. The Roots blower 81 transports the desulfurized biogas to the steam generator 9 for combustion to generate energy, which can be used in conjunction with other equipment to complete the recovery and reuse of the associated biogas in the sewage station.

[0033] Working principle: First, after the sewage in the sewage pool 1 is treated in multiple stages, it enters the anaerobic tank 22 from the first pipe 21 to ferment and produce biogas. Then, the biogas flows out from the second pipe 23 connected to the anaerobic tank 22, passes through the first biogas storage container 3 and the third pipe 41, and enters the dry-wet separator 51 for biogas water separation treatment. This treatment process can reduce the content of hydrogen sulfide in the biogas. Then, the treated biogas enters the desulfurization tower 61 through the seventh pipe 10, the second biogas storage container 7, and the fifth pipe 71 for desulfurization treatment, which can also be combined with dosing. The pump 63 pumps the removal agent in the dosing tank 62 into the desulfurization tower 61 to complete the dosing operation of the desulfurization tower 61. Then, the desulfurized biogas enters the steam generator 9 from the eighth pipeline 11 through the Roots blower 81 and the sixth pipeline 82 to burn and produce energy. It can then be used in conjunction with other equipment to complete the recovery and reuse of the associated biogas in the sewage station (it should be noted that the specific models and specifications of the electrical components involved in this scheme need to be selected and determined based on the actual specifications of the device, and the specific selection and calculation method adopts the existing technology in the field, so it will not be described in detail).

[0034] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes within the technical scope disclosed by the present invention according to the technical scheme and the utility model concept of the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A system for recovering and reusing associated biogas from a sewage station, comprising a sewage pool, an anaerobic reaction device, a flare, a water-gas separation device, a desulfurization device, and a steam generator; characterized in that: A third pipeline is provided at the bottom of the torch, a first biogas storage container is installed at one end of the third pipeline, the first biogas storage container is connected to the anaerobic reaction device, the other end of the third pipeline is connected to the water-gas separation device, a seventh pipeline is installed outside the water-gas separation device, a second biogas storage container is provided at the other end of the seventh pipeline, a fifth pipeline is connected to the outside of the second biogas storage container, the other end of the fifth pipeline is connected to the desulfurization device, an eighth pipeline is installed on the desulfurization device, and a draft mechanism is provided at the other end of the eighth pipeline.

2. The sewage station associated biogas recovery and reuse system according to claim 1, characterized in that: The anaerobic reaction device comprises an anaerobic tank, a first pipeline and a second pipeline. The anaerobic tank is connected to the sewage pool through the first pipeline, and the anaerobic tank is connected to the first biogas storage container through the second pipeline.

3. The sewage station associated biogas recovery and reuse system according to claim 1, characterized in that: A valve is provided at the connection between the third pipeline and the torch.

4. The sewage station associated biogas recovery and reuse system according to claim 1, characterized in that: The water-gas separation device comprises a dry-wet separator, and the dry-wet separator is distributed in two groups.

5. The sewage station associated biogas recovery and reuse system according to claim 4, characterized in that: A safety valve and a pressure gauge are respectively installed on the outside of the dry-wet separator, and a precision filter element is arranged inside the dry-wet separator.

6. The sewage station associated biogas recovery and reuse system according to claim 1, characterized in that: The desulfurization device comprises a desulfurization tower, and the desulfurization tower is distributed in two groups.

7. A sewage station associated biogas recovery and reuse system according to claim 6, characterized in that: A fourth pipeline is installed outside the desulfurization tower, a dosing pump is arranged at the other end of the fourth pipeline, and a dosing tank is installed at one end of the dosing pump.

8. The sewage station associated biogas recovery and reuse system according to claim 1, characterized in that: The air induction mechanism comprises a Roots blower, a negative pressure sensor is arranged at the inlet of the Roots blower, and a pressure transmitter is installed at the outlet of the Roots blower.

9. A sewage station associated biogas recovery and reuse system according to claim 8, characterized in that: The outlet of the Roots blower is connected with a sixth pipeline, and the steam generator is connected with the Roots blower through the sixth pipeline.

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