Biodesulfurization treatment method and biodesulfurization treatment system

Abstract

The present disclosure provides a biological desulfurization treatment method and a biological desulfurization treatment system. The biological desulfurization treatment method includes providing a biological desulfurization treatment system, which includes a desulfurization reaction tank and a desulfurization bacteria culture tank. The desulfurization reaction tank is used to receive a hydrogen sulfide-containing gas, and the desulfurization bacteria culture tank is used to culture desulfurization bacteria and is connected to the desulfurization reaction tank. The desulfurization reaction tank includes a desulfurization reaction zone, which includes at least one desulfurization layer and at least one support layer, and the desulfurization layer and the support layer are stacked in an interleaved manner. The method further includes loading the hydrogen sulfide-containing gas into the biological desulfurization treatment system, allowing the hydrogen sulfide-containing gas to pass through the desulfurization reaction zone to undergo a desulfurization reaction to remove hydrogen sulfide, and discharging the desulfurized gas from the desulfurization reaction tank.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to a biological desulfurization treatment system and a biological desulfurization treatment method, and in particular, to a biological desulfurization treatment system including a desulfurization material configured in a specific manner, and a biological desulfurization treatment method using the aforementioned biological desulfurization treatment system. BACKGROUND

[0002] Generally, the components of biogas include methane gas, carbon dioxide gas, and hydrogen sulfide gas (usually with a concentration of 200 ppmv to 8000 ppmv), and since biogas is a greenhouse gas, it can be used for energy use such as heating and power generation. However, hydrogen sulfide in biogas can cause odor, environmental pollution, and corrosion of power generation equipment, so reducing the hydrogen sulfide content in biogas is an important issue.

[0003] The current commonly used desulfurization methods can be divided into chemical desulfurization and biological desulfurization. Chemical desulfurization mostly uses adsorption desulfurization technology (such as activated carbon and iron oxide) and absorption desulfurization technology (such as water washing technology and alkaline water washing technology), but there are problems such as the need to replace the adsorbent and consume electricity, and the need to consider the treatment of replacing the adsorbent. Biological desulfurization uses microorganisms to perform hydrogen sulfide oxidation reaction, does not produce secondary pollutants, and can recover elemental sulfur or perform sulfate wastewater treatment, which is environmentally friendly, but the initial setup cost of the biological desulfurization equipment is relatively high.

[0004] As mentioned above, although the existing desulfurization technology can generally meet their original intended purposes, it still does not fully meet the needs in all aspects. Developing a desulfurization system with high efficiency, high stability, and low cost is still an issue of concern in the relevant field. SUMMARY

[0005] According to an embodiment of the present disclosure, a biological desulfurization treatment method is provided, including providing a biological desulfurization treatment system, the biological desulfurization treatment system including a desulfurization reaction tank and a desulfurization bacteria culture tank, the desulfurization reaction tank being used to receive a gas containing hydrogen sulfide, the desulfurization bacteria culture tank being used to culture desulfurization bacteria and being connected to the desulfurization reaction tank, the desulfurization reaction tank including a desulfurization reaction zone, the desulfurization reaction zone including at least one desulfurization layer and at least one support layer, and the desulfurization layer and the support layer being stacked in an interleaved manner. The biological desulfurization treatment method further includes loading the gas containing hydrogen sulfide into the biological desulfurization treatment system, allowing the gas containing hydrogen sulfide to pass through the desulfurization reaction zone to perform a desulfurization reaction to remove hydrogen sulfide; and discharging the gas after desulfurization treatment from the desulfurization reaction tank.

[0006] According to another embodiment of the present disclosure, a biological desulfurization treatment system is provided. The biological desulfurization treatment system includes a desulfurization reactor for receiving a gas containing hydrogen sulfide and a desulfurization bacteria culture tank for culturing desulfurization bacteria and connected to the desulfurization reactor. The desulfurization reactor includes a desulfurization reaction zone including at least one desulfurization layer and at least one support layer, and the desulfurization layer and the support layer are stacked in an interleaved manner.

[0007] In order to make the features and advantages of the present disclosure more apparent, preferred embodiments will be described in detail hereinafter with reference to the accompanying drawings, in which: BRIEF DESCRIPTION OF DRAWINGS

[0008] Figure 1 FIG. 1 shows a schematic diagram of a biological desulfurization treatment system according to an embodiment of the present disclosure;

[0009] Figure 2 FIG. 4 shows a graph of the relationship between the loading rate of hydrogen sulfide and the elimination capacity and removal efficiency according to a desulfurization test using the biological desulfurization treatment system according to an embodiment of the present disclosure.

[0010] SYMBOL DESCRIPTION

[0011] 10: biological desulfurization treatment system

[0012] 100: desulfurization reactor

[0013] 100A: desulfurization reaction zone

[0014] 100B: temporary storage zone

[0015] 100C: partition

[0016] 102: gas inlet

[0017] 104: gas outlet

[0018] 110: desulfurization layer

[0019] 110p: porous biological carrier

[0020] 120: support layer

[0021] 120p: support assembly

[0022] 130: sprinkling device

[0023] 200: desulfurization bacteria culture tank

[0024] 300-1, 300-2, 300-3: connecting portion

[0025] F1:circulating liquid

[0026] G:gas containing hydrogen sulfide

[0027] G’:gas after desulfurization treatment

[0028] M1:gas inlet motor

[0029] M2:circulating motor

[0030] M3:aeration device

[0031] O1, O2:operation DETAILED DESCRIPTION

[0032] The biological desulfurization treatment system and the biological desulfurization treatment method of the embodiments of the present disclosure are described in detail below. It should be understood that the following description provides many different embodiments or examples of how to implement various aspects of the present disclosure. Specific components and arrangements are described below to simply and clearly describe some embodiments of the present disclosure. Of course, these are merely examples and not limitations of the present disclosure. In addition, similar and / or corresponding reference numerals can be used to indicate similar and / or corresponding components in different embodiments, in order to clearly describe some embodiments of the present disclosure. However, the use of similar and / or corresponding reference numerals in different embodiments and / or structures does not mean that there is any relationship between the different embodiments and / or structures.

[0033] The embodiments of the present disclosure can be combined with the accompanying Figure 1 It should be understood that the accompanying drawings of the present disclosure are not drawn to scale, and in fact, the size of the components can be arbitrarily enlarged or reduced in order to clearly show the features of the present disclosure.

[0034] In addition, relative terms such as "lower" or "bottom" or "higher" or "top" can be used in the embodiments to describe one component's or feature's relationship to another component or feature as illustrated in the drawings. It should be understood that if the device of the drawings is turned over, the components described as on the "lower" side will become the components on the "higher" side.

[0035] It should be understood that although the terms "first", "second", "third", etc. can be used herein to describe various components, layers, regions or parts, these components, layers, regions or parts should not be limited by these terms. These terms are only used to distinguish different components, layers, regions or parts. Therefore, the first component, layer, region or part discussed below can be referred to as the second component, layer, region or part without departing from the teachings of the present disclosure.

[0036] In addition, in an embodiment of the present disclosure, the terms such as "connected", "interconnected" and the like, unless specifically defined, can refer to two structures being directly in contact, or can refer to two structures not being directly in contact, but can have other structures disposed therebetween.

[0037] Further, the terms such as "about", "substantially" and the like generally mean within 10% or within 5% or within 3% or within 2% or within 1% or within 0.5% of a given value or range. The given value or range is an approximate value or range, i.e., the meaning of "about", "substantially" is implied even if not specifically stated. The term "between a first value and a second value" means that the range includes the first value, the second value and other values therebetween.

[0038] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and the present disclosure, and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

[0039] Embodiments of the present disclosure provide a biological desulfurization treatment system, which includes a desulfurization reaction tank and a desulfurization bacteria culture tank. The desulfurization reaction tank has desulfurization layers and support layers stacked in a staggered form, which can effectively increase the time for the gas to be treated to stay in the desulfurization reaction tank and contact the desulfurization bacteria, thereby improving the desulfurization efficiency. Further, the desulfurization layers and the support layers having specific physical properties can further improve the filling rate of the desulfurization reaction tank and improve the hydrogen sulfide loading capacity, thereby reducing the initial setup cost of the treatment system.

[0040] Figure 1 According to an embodiment of the present disclosure, a schematic diagram of a biological desulfurization treatment system 10 is shown. It should be understood that, for the sake of clarity, part of the components of the biological desulfurization treatment system 10 is omitted in the figure, and only part of the components is schematically shown. According to an embodiment, additional features can be added to the biological desulfurization treatment system 10 described below.

[0041] Please refer to Figure 1The biological desulfurization treatment system 10 includes a desulfurization reaction tank 100 and a desulfurization bacteria culture tank 200 connected to the desulfurization reaction tank 100. In detail, according to an embodiment, the desulfurization bacteria culture tank 200 can be connected to the top of the desulfurization reaction tank 100 through a connecting portion 300-2, and the desulfurization reaction tank 100 and the desulfurization bacteria culture tank 200 are connected in series. The desulfurization reaction tank 100 is used to receive a hydrogen sulfide-containing gas and perform a desulfurization reaction on the hydrogen sulfide-containing gas therein, and the desulfurization bacteria culture tank 200 is used to culture desulfurization bacteria. Furthermore, the desulfurization bacteria cultured in the desulfurization bacteria culture tank 200 can be transported to the desulfurization reaction tank 100, and the desulfurization bacteria can react with the hydrogen sulfide-containing gas to remove hydrogen sulfide in the gas.

[0042] According to another embodiment, the biological desulfurization treatment system 10 can include a plurality of desulfurization reaction tanks 100 and a plurality of desulfurization bacteria culture tanks 200 to treat a larger amount of gas, and the plurality of desulfurization reaction tanks 100 and the plurality of desulfurization bacteria culture tanks 200 can be connected in the aforementioned manner. For example, according to some embodiments, the biological desulfurization treatment system 10 can include 2 to 5 desulfurization reaction tanks 100 and 2 to 5 desulfurization bacteria culture tanks 200.

[0043] According to some embodiments, the desulfurization reaction tank 100 can include a desulfurization reaction zone 100A and a temporary storage zone 100B located below the desulfurization reaction zone 100A and communicating with the desulfurization reaction zone 100A. According to a specific embodiment, a partition 100C is provided between the desulfurization reaction zone 100A and the temporary storage zone 100B, and the partition 100C separates the desulfurization reaction tank 100 into the desulfurization reaction zone 100A and the temporary storage zone 100B. The partition 100C can have a plurality of holes so that liquid can flow between the desulfurization reaction zone 100A and the temporary storage zone 100B.

[0044] According to an embodiment, the height of the desulfurization reaction zone 100A can range from 2 meters (m) to 4 m. According to an embodiment, the height of the temporary storage zone 100B can range from 1 m to 2 m.

[0045] According to an embodiment, the tank material of the desulfurization reaction tank 100 and the desulfurization bacteria culture tank 200 can include, for example, polypropylene, polyethylene, or other suitable corrosion-resistant materials.

[0046] In addition, the desulfurization reaction zone 100A can include at least one desulfurization layer 110 and at least one support layer 120, and the desulfurization layer 110 and the support layer 120 are stacked in an interleaved manner. Specifically, according to a specific embodiment, the support layer 120 can be first disposed on the partition 100C, and then the desulfurization layer 110 is disposed on the support layer 120, and is sequentially stacked in this arrangement (for example, arranged from bottom to top in the order of desulfurization layer 110, support layer 120, desulfurization layer 110, support layer 120...), but the present disclosure is not limited thereto. Alternatively, according to other embodiments, the desulfurization layer 110 can be first disposed on the partition 100C, and then the support layer 120 is disposed on the desulfurization layer 110, and is sequentially stacked in this arrangement (for example, arranged from bottom to top in the order of support layer 120, desulfurization layer 110, support layer 120, desulfurization layer 110...).

[0047] According to some embodiments, each of the desulfurization layers 110 includes a plurality of porous biological carriers 110p, each of the support layers 120 includes a plurality of support components 120p, and the number of the porous biological carriers 110p is greater than the number of the support components 120p. The porous biological carriers 110p can provide an environment for the desulfurization bacteria to attach and grow, and the support components 120p can provide physical support to prevent the porous biological carriers 110p disposed thereon from being excessively compressed to cause air tightness and affect system operation. It should be understood that, since the desulfurization layers 110 and the support layers 120 respectively include a plurality of porous biological carriers 110p and a plurality of support components 120p, in some cases, for example, at the junction of the desulfurization layer 110 and the support layer 120, some of the porous biological carriers 110p and the support components 120p can be mixed.

[0048] According to an embodiment, one desulfurization layer 110 and one support layer 120 can constitute a desulfurization unit, and the biological desulfurization treatment system 10 can include 2 to 10 groups or 2 to 8 groups of desulfurization units, for example, 3 groups, 4 groups, 5 groups, 6 groups, or 7 groups, but not limited thereto. In different embodiments, the number of desulfurization units can also be adjusted according to the actual application situation of the biological desulfurization treatment system 10. According to some embodiments, the ratio of the height of a desulfurization unit to the height of the desulfurization reaction zone 100A can be between 1:1.5 and 1:6.5, or can be between 1:2.5 and 1:5.5, for example, 1:3.5 or 1:4.5, but not limited thereto.

[0049] According to some embodiments, the ratio of the total volume of the multi-layer desulfurization layer 110 to the total volume of the multi-layer support layer 120 (which can also be considered as the ratio of the total volume of the porous biological carrier 110p to the total volume of the support assembly 120p) can be between 2:1 to 5:1, for example, 3:1 or 4:1. Further, according to some embodiments, the ratio of the volume of the desulfurization layer 110 to the volume of the support layer 120 in a desulfurization unit can also be between 2:1 to 5:1, for example, 3:1 or 4:1.

[0050] It should be noted that if the volume ratio of the desulfurization layer 110 to the support layer 120 is too small (e.g., less than 2:1), the desulfurization efficiency of the biological desulfurization treatment system 10 can be reduced due to insufficient amount of the porous biological carrier 110p; on the contrary, if the volume ratio of the desulfurization layer 110 to the support layer 120 is too large (e.g., greater than 5:1), the support layer 120 can not be able to provide sufficient physical support, such that the porous biological carrier 110p is excessively densely compressed to cause air-tight phenomenon.

[0051] According to an embodiment, the compressibility of the porous biological carrier 110p can be greater than the compressibility of the support assembly 120p. According to some embodiments, the hardness of the porous biological carrier 110p can be less than the hardness of the support assembly 120p. According to some embodiments, the pore size of the porous biological carrier 110p can be between 200 micrometers (pm) to 2000 pm or between 1500 pm to 2000 pm. According to some embodiments, the porosity of the porous biological carrier 110p can be less than the porosity of the support assembly 120p, specifically, the porosity of the porous biological carrier 110p can range from greater than 80%, for example, between 80% to 85%, and the porosity of the support assembly 120p can range from greater than 90%, for example, between 90% to 95%. According to a specific embodiment, the support assembly 120p can be a hollow shell, and a portion of the porous biological carrier 110p can be disposed in the support assembly 120p.

[0052] Further, according to another embodiment, the specific surface area of the porous biological carrier 110p is greater than the specific surface area of the support assembly 120p. Specifically, according to some embodiments, the specific surface area of the porous biological carrier 110p can be between 800 meters 2 / meter 3 (m 2 / meter 3 ) to 8000 meters 2 / meter 3 , and the specific surface area of the support assembly 120p can be between 150 meters 2 / meter 3 to 4000 meters 2 / meter 3 .2 / m 3 to 500 m 2 / m 3 .

[0053] Further, as mentioned above, the desulfurization reaction tank 100 has a partition 100C with a plurality of holes, and according to some embodiments, the size (e.g., diameter) of the porous biological carrier 110p and the support assembly 120p is greater than the size (e.g., diameter) of the holes of the partition 100C, so that the porous biological carrier 110p or the support assembly 120p can avoid blocking the holes, and interfere with the flow of liquid between the desulfurization reaction zone 100A and the temporary storage zone 100B.

[0054] According to some embodiments, the material of the porous biological carrier 110p can include polyurethane (PU), porous foam, polyvinyl alcohol (PVA), polyethylene (PE), or a combination thereof, but is not limited thereto. According to some embodiments, the material of the support assembly 120p can include polyurethane (PU), polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC), poly(methyl methacrylate) (PMMA), Teflon, polyvinylidene fluoride (PVDF), ceramic, carbon steel, or a combination thereof, but is not limited thereto.

[0055] Notably, the aforementioned porous biological carrier 110p with high specific surface area, high porosity, and high permeability can provide a good environment for the attachment and growth of desulfurization bacteria (e.g., autotrophic aerobic desulfurization bacteria), thereby performing high-concentration hydrogen sulfide removal treatment. In detail, the porous biological carrier 110p can effectively intercept hydrogen sulfide gas, increase the gas residence time, avoid gas short-circuiting, and at the same time, can also increase the contact area and contact time of hydrogen sulfide gas and circulating liquid, and increase the time of desulfurization reaction.

[0056] Further, since the support layer 120 is composed of the support assembly 120p, rather than a plate-type support layer, the following problems that can occur when using a plate-type support layer can be overcome: the number and density of flow holes are limited by the area of the plate material, and if the porous biological carrier is used for a long time, the porous biological carrier can be compacted and blocked in the flow holes due to the attachment of elemental sulfur or microorganisms, affecting system operation; and when backwashing is performed, the desulfurization layer and the support layer are not easily disturbed, and the backwashing effect cannot be effectively achieved.

[0057] Furthermore, by using the combination of the porous bio-carriers 110p having the specific physical characteristics and the support assembly 120p in conjunction with the specific arrangement of the desulfurization layer 110 and the support layer 120, the packing ratio of the porous bio-carriers 110p and the support assembly 120p in the desulfurization reaction zone 100A (i.e., the carrier packing ratio) can be effectively improved, and the hydrogen sulfide load that the biological desulfurization treatment system 10 can bear can be improved. Specifically, according to some embodiments, the packing ratio of the porous bio-carriers 110p and the support assembly 120p in the desulfurization reaction zone 100A can be between 80% and 95%, or between 90% and 95%. According to some embodiments, the volumetric loading rate of hydrogen sulfide of the biological desulfurization treatment system 10 can be between 30 g H2S / m 3 hr and 250 g H2S / m 3 hr, or between 30 g H2S / m 3 hr and 210 g H2S / m 3 hr, or between 30 g H2S / m 3 hr and 160 g H2S / m 3 hr. 3

[0058] Furthermore, by using the combination of the porous bio-carriers 110p having the specific physical characteristics and the support assembly 120p in conjunction with the specific arrangement of the desulfurization layer 110 and the support layer 120, the biological desulfurization treatment system 10 is able to operate at a high trickling flow rate, and a large amount of dissolved oxygen can be stably provided for the desulfurization bacteria. Specifically, according to some embodiments, the trickling flow rate of the circulating liquid in the biological desulfurization treatment system 10 can be between 20 meters per hour (m / hr) and 50 m / hr, for example, 30 m / hr or 40 m / hr. It should be noted that if the trickling flow rate of the circulating liquid is too low (e.g., lower than 20 m / hr), the oxygen transfer efficiency and the hydrogen sulfide dissolution rate will be affected, resulting in poor desulfurization effect. The operation mode of the biological desulfurization treatment system 10 will be described in detail below.

[0059] It is worth noting that in the biological trickling bed technology, the carrier packing ratio and the trickling flow rate are two important system parameters. Specifically, a high packing ratio means that more hydrogen sulfide can be borne in a unit volume of the desulfurization reaction tank, so under the same hydrogen sulfide treatment load, the biological desulfurization treatment system can maintain a high-efficiency hydrogen sulfide removal effect in a relatively small tank volume, thereby reducing the initial setup cost of the treatment system.

[0060] Please refer to Figure 1 ​According to some embodiments, the top portion of the desulfurization reaction tank 100 can have a water spraying device 130, which can control the flow rate of the liquid into the desulfurization reaction tank 100, and can atomize the liquid, reduce the droplet size, thereby increasing the contact surface area of the liquid with the gas. In addition, according to some embodiments, the desulfurization reaction tank 100 further comprises a gas inlet 102 and a gas outlet 104, the gas inlet 102 is disposed on the side surface of the desulfurization reaction tank 100 and corresponds to the desulfurization reaction zone 100A, and the gas outlet 104 is disposed on the top portion of the desulfurization reaction tank 100. Specifically, according to some embodiments, the gas G containing hydrogen sulfide can enter the desulfurization reaction zone 100A of the desulfurization reaction tank 100 from the gas inlet 102, and after the desulfurization reaction is carried out, the gas G' treated by desulfurization can exit the desulfurization reaction tank 100 from the gas outlet 104. In addition, according to some embodiments, the gas inlet 102 can have an air inlet motor M1, which can guide the gas containing hydrogen sulfide into the desulfurization reaction tank 100, and can control the air inlet flow rate, etc.

[0061] According to some embodiments, the temporary storage zone 100B can be connected to the desulfurization bacteria culture tank 200 through a connecting portion 300-1, in detail, the connecting portion 300-1 can be disposed between the side surface corresponding to the temporary storage zone 100B of the desulfurization reaction tank 100 and the side surface of the desulfurization bacteria culture tank 200. In addition, according to some embodiments, the desulfurization bacteria culture tank 200 can be connected to the top portion of the desulfurization reaction tank 100 through a connecting portion 300-2, in detail, the connecting portion 300-2 can be disposed between the top surface corresponding to the desulfurization reaction zone 100A of the desulfurization reaction tank 100 and the side surface of the desulfurization bacteria culture tank 200. According to some embodiments, the connecting portion 300-2 can be connected to a circulating motor M2, which can be disposed in the connecting portion 300-2, and the circulating motor M2 can provide power to circulate the liquid between the desulfurization bacteria culture tank 200 and the desulfurization reaction tank 100, for example, to transport the liquid and the desulfurization bacteria in the desulfurization bacteria culture tank 200 to the desulfurization reaction tank 100, and to transport the liquid in the temporary storage zone 100B of the desulfurization reaction tank 100 back to the desulfurization bacteria culture tank 200.

[0062] According to some embodiments, the connecting portion 300-1 and the connecting portion 300-2 can comprise a pipeline, and the material of the pipeline can comprise metal, non-metal, or a combination thereof. For example, the metal can comprise stainless steel, copper, aluminum, or a combination thereof, but is not limited thereto. The non-metal can comprise silica gel, Teflon, rubber, or plastic (for example, polyurethane (PU), polypropylene (PP), polyvinyl fluoride (PVC), polyethylene (PE), polymethyl methacrylate (PMMA)), or a combination thereof, but is not limited thereto.

[0063] In addition, as Figure 1As shown, according to some embodiments, the biological desulfurization system 10 may further include an aeration device M3, which can be connected to the bottom of the desulfurization reaction tank 100 and the bottom of the desulfurization bacteria culture tank 200 via a connecting part 300-3. According to some embodiments, the aeration device M3 can be connected to the desulfurization reaction tank 100 and the desulfurization bacteria culture tank 200 respectively via different connecting parts 300-3, and can aerate the desulfurization reaction tank 100 and the desulfurization bacteria culture tank 200 respectively according to different needs (e.g., desulfurization mode or cleaning mode).

[0064] In detail, the desulfurization bacteria cultivation tank 200 provides sufficient oxygen for the desulfurization bacteria through aeration, converting reduced hydrogen sulfide into oxidized sulfate, thus achieving high-efficiency desulfurization. Furthermore, it is worth noting that because the desulfurization bacteria cultivation tank 200 uses external aeration to proliferate the desulfurization bacteria in large quantities, it avoids the introduction of hydrogen sulfide-containing gas G into the air, which would affect its composition. Moreover, the desulfurization reaction tank 100 can be backwashed by the aeration device M3 to wash away elemental sulfur and aged desulfurization bacteria accumulated in the desulfurization reaction zone 100A.

[0065] According to some embodiments, the desulfurization bacteria culture tank 200 may be further configured with pH, ​​redox potential, dissolved oxygen, and conductivity controllers (not shown). The pH, redox potential, dissolved oxygen, and conductivity controllers can be used to monitor the water quality parameters such as pH, redox potential, dissolved oxygen, and conductivity of the substances in the desulfurization bacteria culture tank 200. The timing of water replacement or addition of nutrient substrate can be determined based on the changes in the values ​​of water quality parameters such as pH, redox potential, dissolved oxygen, and conductivity.

[0066] Furthermore, this disclosure also provides a biological desulfurization treatment method, comprising using the aforementioned biological desulfurization treatment system 10 to desulfurize the gas. The biological desulfurization treatment method will be described below in terms of the operation mode of the biological desulfurization treatment system 10. It should be understood that, according to some embodiments, additional steps may be added before, during, and / or after the biological desulfurization treatment method described below, or some steps may be replaced or omitted.

[0067] like Figure 1 As shown, hydrogen sulfide-containing gas G can be loaded into the biological desulfurization system 10, allowing it to undergo a desulfurization reaction in the desulfurization reaction zone 100A to remove hydrogen sulfide. Specifically, the hydrogen sulfide-containing gas G can be introduced into the desulfurization reaction zone 100A of the desulfurization reaction tank 100 via the gas inlet 102 by turning on the intake motor M1. According to some embodiments, the hydrogen sulfide-containing gas G may contain biogas, but is not limited to this. According to some embodiments, the intake flow rate of the hydrogen sulfide-containing gas G may be between 0.01 m³ / s. 3 / minute (m 3 / min) to 10 meters 3 Between / minute, or between 1 minute 3 / min to 8m 3 Between / min.

[0068] After the hydrogen sulfide-containing gas G enters the desulfurization reaction tank 100, it moves upward from the bottom of the desulfurization reaction zone 100A. Through interaction with the desulfurization bacteria attached to the desulfurization layer 110 and the support layer 120, it reduces the sulfur ions (S2) in the hydrogen sulfide. 2- ) oxidized to elemental sulfur (S) 0 ) and sulfate ions (SO4) 2- This allows the hydrogen sulfide-containing gas G to undergo a desulfurization reaction. After the desulfurization reaction of the hydrogen sulfide-containing gas G is completed, the desulfurized gas G' is discharged from the desulfurization reaction tank 100 through the gas outlet 104.

[0069] According to some embodiments, the desulfurizing bacteria may be autotrophic desulfurizing bacteria, including *Acidthiobacillus* spp., *Mycobacterium* spp., *Thiomonas* spp., or other suitable desulfurizing bacteria. Specifically, in the desulfurization reaction tank 100, the hydrogen sulfide-containing gas G reacts with oxygen in the circulating liquid (Equation 1) and undergoes a redox reaction with the desulfurizing bacteria in an aerobic environment (Equations 2 and 3), the reaction formulas of which are shown below:

[0070] H₂S + 0.5O₂ → S 0 +2H₂O (-209kJ / reaction; O₂ / H₂S = 0.5) [Equation 1]

[0071] S 0 +1.5O2 + H2O → SO4 2- +2H+(-587kJ / reaction; O2 / H2S=1.5)[Equation 2]

[0072] H₂S + 2O₂ → SO₄ 2- +2H+(-798kJ / reaction; O2 / H2S=2.0)[Equation 3]

[0073] According to the embodiments of the present disclosure, the biological desulfurization system 10 can operate at a high trickling flow rate, and can stably provide a large amount of dissolved oxygen for the use of the desulfurization bacteria. As shown above, in the case of sufficient oxygen (e.g., the ratio of oxygen to hydrogen sulfide is greater than 1.5), the generation of elemental sulfur can be avoided (Formula 1), so that the final reaction product of the gas G containing hydrogen sulfide in the desulfurization reaction tank 100 is sulfate (as shown in Formulas 2 and 3). In addition, under the operation of a high trickling flow rate, the amount of dissolved carbon dioxide (which can be used as a carbon source for autotrophic microorganisms) and hydrogen sulfide (target reactant) in the biogas also relatively increases, thereby providing a more favorable environment for the reaction of autotrophic desulfurization bacteria.

[0074] The biological desulfurization system 10 provided by the embodiments of the present disclosure can have a desulfurization mode and a cleaning mode. First, the desulfurization mode is described. When the desulfurization mode is performed, the liquid in the desulfurization reaction tank 100 and the desulfurization bacteria culture tank 200 is circulated. Figure 1 The desulfurization bacteria in the desulfurization bacteria culture tank 200 can be transported to the desulfurization reaction tank 100 through the circulating liquid F1 (the arrows in the figure can be understood as the flow direction of the liquid), and attached to the desulfurization layer 110 of the desulfurization reaction zone 100A. The desulfurization bacteria in the desulfurization reaction zone 100A can perform a desulfurization reaction on the gas G containing hydrogen sulfide. The detailed reaction steps of the desulfurization bacteria and hydrogen sulfide are described above, and will not be repeated here.

[0075] As described above, the desulfurization bacteria culture tank 200 can be connected to the desulfurization reaction tank 100 through the connecting portion 300-2. According to some embodiments, the desulfurization bacteria culture tank 200 can contain desulfurization bacteria, water, sulfate ions, nutrient bases, or other suitable components, and the components of the circulating liquid F1 are the same. As described above, the desulfurization bacteria cultured in the desulfurization bacteria culture tank 200 can be autotrophic desulfurization bacteria, including Acidthiobacillus spp., Mycobacterium spp., Thiomonas spp., or other suitable desulfurization bacteria. According to some embodiments, the species cultured in the desulfurization bacteria culture tank 200 can include 40-50% of Acidthiobacillus spp., 10-20% of Mycobacterium spp., and 5-15% of Thiomonas spp., but is not limited thereto. In addition, according to some embodiments, the desulfurization bacteria culture tank 200 can further contain other species that are beneficial to the growth of microorganisms.

[0076] Next, the circulating liquid F1 flows from the desulfurization reaction zone 100A to the temporary storage zone 100B, and transports part of the products of the desulfurization reaction to the temporary storage zone 100B, for example, transports the sulfate ions generated after the desulfurization reaction to the temporary storage zone 100B. In addition, as shown in Figure 1As shown, the temporary storage zone 100B is connected to the desulfurization bacteria culture tank 200 through the connecting part 300-1, so that the circulating liquid F1 can be circulated to the desulfurization bacteria culture tank 200 to provide nutrients for the desulfurization bacteria. In detail, part of the elements or ions in the circulating liquid F1 can be used as the nutrient source for the desulfurization bacteria. It is worth noting that the desulfurization reaction zone 100A adopts a reverse flow mode, that is, the running direction of the circulating liquid F1 is opposite to that of the gas G containing hydrogen sulfide.

[0077] In addition, in the desulfurization mode of the biological desulfurization treatment system 10, the aeration device M3 is operated O1 to deliver air into the desulfurization bacteria culture tank 200 (the arrows in the figure can be understood as the flow direction of the gas) to provide oxygen for the desulfurization bacteria. In detail, the aeration device M3 can deliver air into the desulfurization bacteria culture tank 200 through the connecting part 300-3 to increase the oxygen content of the liquid in the desulfurization bacteria culture tank 200. Moreover, since the desulfurization bacteria culture tank 200 adopts an external aeration method to proliferate the desulfurization bacteria in large quantities, air can be prevented from mixing into the gas G containing hydrogen sulfide to affect its composition.

[0078] On the other hand, when the biological desulfurization treatment system 10 is in the cleaning mode, the liquid circulation between the desulfurization reaction tank 100 and the desulfurization bacteria culture tank 200 is first suspended, and in the cleaning mode, the aeration device M3 is operated O2 to deliver air into the desulfurization reaction tank 100 (the arrows in the figure can be understood as the flow direction of the gas) to clean the desulfurization layer 110 and the support layer 120. In detail, the aeration device M3 can deliver air into the temporary storage zone 100B and the desulfurization reaction zone 100A in the desulfurization reaction tank 100 through the connecting part 300-3. In particular, since the porous biological carrier 110p has compressibility, combined with the foregoing backwashing operation, the elemental sulfur solids attached to the surface of the porous biological carrier 110p can be effectively removed, and the aged desulfurization bacteria can be replaced to release the occupied reaction space, maintain high desulfurization efficiency, and prevent the gas from being short-circuited due to long-time operation.

[0079] In order to make the above and other objects, features, and advantages of the present disclosure more apparent, the following describes several embodiments and comparative examples in detail, but the present disclosure is not limited thereto.

[0080] Embodiment 1

[0081] The desulfurization capacity test using the foregoing biological desulfurization treatment system 10 is described in detail as follows. First, the inlet gas concentration of the biogas is measured, and the inlet gas quality of the biogas is controlled (the concentration of methane needs to be greater than 55%, and the concentration of carbon dioxide needs to be less than 25%). Then, the inlet gas motor is started (0.05m 3 / min to 0.25m 3 / min). After the air intake motor was turned on, the circulation motor (9m 3 / hr), then, after the biodesulfurization treatment system 10 was allowed to process (desulfurization mode) for 1 hour, the concentration of the biogas at the outlet was measured, the results were recorded, and the desulfurization efficiency (hydrogen sulfide removal efficiency) was calculated. The desulfurization capacity was tested at five different hydrogen sulfide loading rates (46, 93, 127, 160, and 206 g H2S / m 3 / hr) were evaluated. The experimental contents and results are shown in Table 1 and Figure 2 Furthermore, the hydrogen sulfide loading rate, the hydrogen sulfide elimination capacity, and the removal efficiency were calculated as follows:

[0082] Hydrogen sulfide loading rate = air intake flow rate (m 3 / hr) x hydrogen sulfide concentration at the air intake (mg / L) / volume of the desulfurization reaction zone 100A (m 3 )

[0083] Elimination capacity = air intake flow rate (m 3 / hr) x hydrogen sulfide concentration at the outlet (mg / L) / volume of the desulfurization reaction zone 100A (m 3 )

[0084] Removal efficiency = (hydrogen sulfide concentration at the air intake - hydrogen sulfide concentration at the outlet) / hydrogen sulfide concentration at the air intake x 100%

[0085] Table 1

[0086]

[0087]

[0088] As shown in Table 1 and Figure 2 , at a low hydrogen sulfide loading rate of 46 g H2S / m 3 / hr, the hydrogen sulfide elimination capacity was 46 g H2S / m 3 / hr, and the hydrogen sulfide removal efficiency was 99%; when the hydrogen sulfide loading rate was increased to 160 g H2S / m 3 / hr, the hydrogen sulfide elimination capacity was slightly reduced, but the hydrogen sulfide removal efficiency was still 89%. As shown above, when the hydrogen sulfide loading rate was about 40-130 g H2S / m 3Under the conditions of 170-209 gH2S / m

[0089] Comparative Example 1

[0090] Comparing with the experimental data in the literature "Biogas biological desulphurisation under extremely acidic conditions for energetic valorisation in Solid Oxide Fuel Cells", Chemical Engineering Journal 255 (2014) 677-685. In the aforementioned literature, the biogas desulphurisation reaction was carried out using a bio-trickling filter, and the packing material in the desulphurisation reactor was all HD-QPAC. Under the conditions of 170-209 gH2S / m 3 hr (average 195 gH2S / m 3 hr), the removal capacity of hydrogen sulphide was 142-190 gH2S / m 3 hr (average 169 gH2S / m 3 hr), and the removal efficiency of hydrogen sulphide was 72-94% (average 84%).

[0091] Comparative Example 2

[0092] Comparing with the experimental data in the literature "Performance and Economic Results for two Full Scale Biotrickling Filters To Remove H2S from Dairy Manure-Derived Biogas", Applied Engineering in Agriculture, 35(3), 283-291. In the aforementioned literature, the biogas desulphurisation reaction was carried out using a bio-trickling filter, and the packing material in the desulphurisation reactor was all circular polypropylene structure, and was implemented in Farm 1 and Farm 2. The desulphurisation reactor in Farm 1 had two compartments (i.e. had two layers of spacing), and the desulphurisation reactor in Farm 2 only had one compartment (i.e. did not have multiple layers of spacing). In Farm 1, under the conditions of 33 gH2S / m 3 hr, the removal efficiency of hydrogen sulphide was 94.5%; in Farm 2, under the conditions of 37 gH2S / m 3 hr, the removal efficiency of hydrogen sulphide was 80.1%.

[0093] According to the results of the embodiment 1 and the comparative examples 1-2, it is known that the biological desulfurization treatment system provided in the present disclosure has better hydrogen sulfide removal capacity and hydrogen sulfide removal efficiency under the same hydrogen sulfide load rate.

[0094] In summary, in the biological desulfurization treatment system provided in the embodiments of the present disclosure, the desulfurization reaction tank contains desulfurization layers and support layers stacked in an interleaved manner. Compared with the desulfurization system generally using plate-shaped filler materials or a single type of filler material, the time for the gas to be treated to stay in the desulfurization reaction tank and contact with the desulfurization bacteria can be effectively increased, thereby improving the desulfurization efficiency. Furthermore, the desulfurization layers and the support layers having specific physical properties can further improve their filling rate and increase the hydrogen sulfide load capacity, thereby reducing the initial setup cost of the treatment system. In addition, the desulfurization bacteria culture tank uses an external aeration method, which can provide sufficient oxygen for a large amount of desulfurization bacteria and can avoid air mixing into the gas to be treated, thereby maintaining stable air quality.

[0095] Although the embodiments of the present disclosure and their advantages have been disclosed as above, it should be understood that any person with ordinary knowledge in the art can make modifications, replacements and refinements without departing from the spirit and scope of the present disclosure. In addition, the protection scope of the present disclosure is not limited to the processes, machines, manufactures, compositions of matter, means, methods and steps in the specific embodiments described in the specification. Any person with ordinary knowledge in the art can understand the current or future developed processes, machines, manufactures, compositions of matter, means, methods and steps from the disclosure content of the present disclosure, as long as they can substantially achieve the same function or obtain substantially the same results as in the embodiments described herein. Therefore, the protection scope of the present disclosure includes the aforementioned processes, machines, manufactures, compositions of matter, means, methods and steps. In addition, each claim constitutes an individual embodiment, and the protection scope of the present disclosure also includes the combination of each claim and embodiment. The protection scope of the present disclosure is subject to the scope defined by the appended claims.

Claims

1. A biological desulfurization treatment method characterized by comprising: include: Provide a biological desulfurization system, including: A desulfurization reaction tank for receiving gas containing hydrogen sulfide; and A desulfurization bacteria culture tank, used to cultivate desulfurization bacteria, is connected to the desulfurization reaction tank; The desulfurization reaction tank includes a desulfurization reaction zone, which includes at least one desulfurization layer and at least one support layer. The at least one desulfurization layer includes multiple porous biological carriers, and the at least one support layer includes multiple support components. The at least one desulfurization layer and the at least one support layer are stacked in an alternating manner. The support component is a hollow shell, and the compressibility of the porous biological carrier is greater than that of the support component. A gas containing hydrogen sulfide is loaded into the biological desulfurization system, and the gas containing hydrogen sulfide is passed through the desulfurization reaction zone to carry out a desulfurization reaction to remove hydrogen sulfide. The desulfurized gas is discharged from the desulfurization reaction tank; and An aeration device is provided, which is connected to the bottom of the desulfurization reaction tank and the bottom of the desulfurization bacteria culture tank. In the cleaning mode of the biological desulfurization treatment system, the aeration device delivers air to the desulfurization reaction tank to clean the at least one desulfurization layer and the at least one support layer.

2. The biological desulfurization treatment method according to claim 1, characterized by, The desulfurizing bacteria in the desulfurizing bacteria culture tank are transported to the desulfurizing reaction tank through a circulating liquid and attach to at least one desulfurization layer in the desulfurization reaction zone, wherein the desulfurizing bacteria in the desulfurization reaction zone perform a desulfurization reaction on the gas containing hydrogen sulfide.

3. The biological desulfurization treatment method according to claim 2, characterized by, The desulfurization reaction tank also includes a temporary storage area located below and connected to the desulfurization reaction area, wherein the circulating liquid flows from the desulfurization reaction area to the temporary storage area, and the products of the desulfurization reaction are transported to the temporary storage area.

4. The biological desulfurization treatment method according to claim 3, characterized by The temporary storage area is connected to the desulfurization bacteria culture tank, so that the circulating liquid is circulated to the desulfurization bacteria culture tank to provide nutrients for the desulfurization bacteria.

5. The biological sweetening process according to claim 2, wherein In the desulfurization reaction zone, the direction of travel of the circulating liquid is opposite to the direction of travel of the gas containing hydrogen sulfide.

6. The biological sweetening process of claim 1 wherein, In the desulfurization mode of the biological desulfurization treatment system, the aeration device delivers air to the desulfurization bacteria culture tank to provide oxygen for the deoxygenated bacteria.

7. The biological desulfurization treatment method according to claim 1, characterized by The inlet flow rate of the hydrogen sulfide-containing gas is between 0.01 m³ / min and 10 m³ / min.

8. The biological sweetening process according to claim 2, wherein The drip rate of the circulating liquid in this biological desulfurization system is between 20 m / h and 50 m / h.

9. The biological desulfurization treatment method according to claim 1, characterized by, The filling rate of the multiple porous biological carriers and the multiple support components in the desulfurization reaction zone is between 80% and 95%.

10. A biological desulfurization treatment system characterized by comprising: include: A desulfurization reaction tank is used to receive gas containing hydrogen sulfide; A desulfurization bacteria culture tank, used to cultivate desulfurization bacteria, is connected to the desulfurization reaction tank; as well as An aeration device is connected to the bottom of the desulfurization reaction tank and the bottom of the desulfurization bacteria culture tank via a connecting part. The desulfurization reaction tank includes a desulfurization reaction zone, which includes at least one desulfurization layer and at least one support layer. The at least one desulfurization layer includes multiple porous biological carriers, and the at least one support layer includes multiple support components. The at least one desulfurization layer and the at least one support layer are stacked in an alternating manner. The support component is a hollow shell, and the compressibility of the porous biological carrier is greater than that of the support component.

11. The biological desulfurization treatment system according to claim 10, wherein The number of porous biological carriers is greater than the number of supporting components.

12. The biological desulfurization treatment system according to claim 11, characterized by The filling rate of the multiple porous biological carriers and the multiple support components in the desulfurization reaction zone is between 80% and 95%.

13. The biological desulfurization system according to claim 11, characterized in that, The pore size of this porous biological carrier ranges from 200 micrometers to 2000 micrometers.

14. The biological desulfurization system according to claim 11, characterized in that, The porosity of the porous biological carrier is less than that of the support component.

15. The biological desulfurization system according to claim 11, characterized in that, The specific surface area of ​​the porous biological carrier is greater than that of the support component.

16. The biological desulfurization system according to claim 10, characterized in that, The ratio of the total volume of the at least one desulfurization layer to the total volume of the at least one support layer is between 2:1 and 5:

1.

17. The biological desulfurization system according to claim 10, characterized in that, The at least one desulfurization layer and the at least one support layer constitute a set of desulfurization units, and the biological desulfurization treatment system includes 2 to 10 sets of desulfurization units.

18. The biological desulfurization system according to claim 17, characterized in that, In this desulfurization unit, the volume ratio of the desulfurization layer to the support layer is between 2:1 and 5:

1.

19. The biological desulfurization system according to claim 17, characterized in that, The ratio of the height of the desulfurization unit to the height of the desulfurization reaction zone is between 1:1.5 and 1:6.

5.

20. The biological desulfurization system according to claim 10, characterized in that, The desulfurization reaction tank also includes a temporary storage area located below and connected to the desulfurization reaction area.

21. The biological desulfurization system according to claim 20, characterized in that, The temporary storage area is connected to the desulfurization bacteria culture tank.

22. The biological desulfurization system according to claim 10, characterized in that, The desulfurization bacteria culture tank is connected to the top of the desulfurization reaction tank via a connector.

23. The biological desulfurization system according to claim 10, characterized in that, It also includes a gas inlet and a gas outlet, wherein the gas inlet is disposed on the side surface of the desulfurization reaction tank and corresponds to the desulfurization reaction zone, and the gas outlet is disposed on the top of the desulfurization reaction tank.

24. The biological desulfurization system according to claim 10, characterized in that, Its hydrogen sulfide volume loading rate ranges from 30 g H2S / m3h to 250 g H2S / m3h.

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