A composition for inhibiting hydrogen sulfide production in a drainage system and methods of use thereof
By combining NO donor and tetrahydroxymethyl phosphate, NO-induced biofilm dispersion and inhibition of sulfate-reducing bacteria metabolism are utilized, solving the problems of reduced inhibitor efficacy and environmental impact caused by biofilm barriers, and achieving efficient and economical hydrogen sulfide reduction.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- GUIZHOU MINZU UNIV
- Filing Date
- 2025-10-30
- Publication Date
- 2026-05-29
Smart Images
Figure CN121269966B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of wastewater treatment technology, and more specifically to a composition for inhibiting the generation of hydrogen sulfide in drainage systems and its application method. Background Technology
[0002] Sulfate reduction is a crucial part of the biogeochemical sulfur cycle. Under anaerobic conditions, sulfate-reducing bacteria (SRB) in the biofilm on the inner walls of drainage pipes utilize organic matter in wastewater as electron donors to reduce sulfate to sulfides, with hydrogen sulfide being the primary product. Hydrogen sulfide is a flammable, toxic, and foul-smelling gas. In humid environments, hydrogen sulfide is oxidized to sulfuric acid by sulfur-oxidizing bacteria, which then corrodes drainage pipes and water treatment structures.
[0003] Currently, technologies for controlling hydrogen sulfide generation in drainage systems mainly fall into two categories: one is to inhibit sulfide formation at the source, and the other is to remove existing sulfides. Among these, inhibiting sulfide formation at the source has a broader application prospect.
[0004] In drainage systems, SRBs primarily adhere to the inner walls of drainage structures and pipes in the form of biofilms. The SRB biofilm mainly consists of SRBs and extracellular polymeric substances (EPS) surrounding them. EPS has abundant negatively charged groups, which can resist different types of inhibitors through physical adsorption and electrostatic interactions, reducing the diffusion rate of inhibitors within the biofilm and protecting SRB cells from direct contact with inhibitors. This EPS-mediated protective mechanism significantly reduces the sensitivity of SRBs within the biofilm to inhibitors, leading to decreased inhibitor efficacy and high agent consumption. Furthermore, most current agents for inhibiting hydrogen sulfide production (such as glutaraldehyde and molybdate) have significant environmental impacts. Summary of the Invention
[0005] To address the shortcomings of existing technologies, this invention provides a composition and its application method for inhibiting hydrogen sulfide generation in drainage systems. This invention overcomes the barrier effect of EPS (excessive saline-phosphorus hydroxide) on inhibitor diffusion through a synergistic mechanism of "NO-induced biofilm dispersion-precise inhibition of SRB metabolism," thus overcoming the drawbacks of traditional technologies such as low SRB sensitivity and high reagent dosage due to biofilm protection. This achieves efficient, economical, and green hydrogen sulfide source reduction. Furthermore, the tetramethylolsulfate of this invention exhibits good biodegradability and environmental safety, solving the problem of significant environmental impact associated with most current hydrogen sulfide generation inhibitors (such as glutaraldehyde and molybdate).
[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows:
[0007] The first objective of this invention is to provide a composition for inhibiting hydrogen sulfide production in a drainage system, comprising an NO donor and tetramethylolpropionic acid phosphate; wherein the NO donor releases trace amounts of NO, which induces the dispersion of sulfate-reducing bacteria biofilm by interfering with the metabolism of the quorum sensing signal molecule c-di-GMP, thereby weakening the protective effect of extracellular polymers in the sulfate-reducing bacteria biofilm on the sulfate-reducing bacteria; then, the production of hydrogen sulfide is inhibited by the inhibition of the metabolic activity of sulfate-reducing bacteria by tetramethylolpropionic acid phosphate.
[0008] The mass ratio of NO donor to tetrahydroxymethylphosphoric acid is 1:2~2.5.
[0009] Preferably, the mass ratio of NO donor to tetrahydroxymethylphosphoric acid is 1:2.5.
[0010] Preferably, the NO donor is selected from sodium nitroprusside, S-nitroso-N-acetylpenicillamine, or S-nitrosoglutathione.
[0011] Preferably, the NO donor is sodium nitroprusside, which is currently the most commonly used NO donor and can release about one part per thousand of NO in aqueous solution.
[0012] A second objective of this invention is to provide a method for applying a composition for inhibiting hydrogen sulfide production in a drainage system. Using the aforementioned composition as an inhibitor, the inhibitor is added to a drainage system containing a sulfate-reducing bacteria biofilm, followed by cultivation. Since it is difficult to accurately quantify the bacterial concentration in a biofilm system, this invention only requires ensuring that the SRB biofilm is completely attached to the drainage pipe wall and has a thickness of several millimeters.
[0013] Preferably, the cultivation conditions are: incubation in a dark anaerobic environment at 10℃~30℃ for 24h.
[0014] Preferably, the mass ratio of NO donor to sulfide in the drainage system is 10:50, and the mass ratio of tetrahydroxymethylphosphonic acid to sulfide in the drainage system is 20~25:50.
[0015] Compared with the prior art, the present invention has the following beneficial effects:
[0016] 1. This invention provides a composition for inhibiting hydrogen sulfide (SRB) production in drainage systems, comprising an NO donor and tetramethylolpropionic acid (TMA); the mass ratio of NO donor to TMA is 1:2~2.5. The NO donor releases NO, which interferes with the metabolism of the quorum sensing signal molecule c-di-GMP, inducing the dispersion of sulfate-reducing bacteria (SRB) biofilms, thereby weakening the protective effect of extracellular polymers on SRBs. Then, TMA inhibits the metabolic activity of SRBs, thereby inhibiting hydrogen sulfide production. This invention overcomes the barrier effect of EPS on inhibitor diffusion through a synergistic mechanism of "NO-induced biofilm dispersion - TMA precisely inhibiting SRB metabolism," overcoming the shortcomings of traditional technologies such as low SRB sensitivity and high agent dosage due to biofilm protection. Furthermore, because TMA has good biodegradability and environmental safety, it solves the problem of significant environmental impact associated with most current hydrogen sulfide inhibitors (such as glutaraldehyde and molybdate), achieving efficient, economical, and green source reduction of hydrogen sulfide.
[0017] Tetrahydroxymethyl phosphate (THPS) contains positively charged phosphorus atoms, which can adsorb onto the negatively charged bacterial surface, react with the cell membrane, alter its permeability, and disrupt enzyme activity. Furthermore, THPS releases tris(hydroxymethyl)phosphine (THP) under alkaline conditions. THP has reducing properties and can break disulfide bonds (SS) in sulfur-containing amino acids in biofilms, thus disrupting cell structure. Based on this, THPS inhibits the metabolic processes of sulfate-reducing bacteria (SRB) by disrupting the cell membrane structure.
[0018] 2. This invention also provides a method for applying a composition for inhibiting hydrogen sulfide production in drainage systems. The method involves adding an NO donor and tetramethylolpropionate sulfate to a drainage system containing a sulfate-reducing bacterial biofilm, followed by cultivation. The inhibitory concentration index of the combined addition of the NO donor and tetramethylolpropionate sulfate is less than 0.5, indicating a strong synergistic effect between the NO donor and tetramethylolpropionate sulfate in inhibiting hydrogen sulfide production. Attached Figure Description
[0019] Figure 1 This is a diagram illustrating the mechanism by which a composition used to suppress hydrogen sulfide generation in a drainage system inhibits hydrogen sulfide production.
[0020] Figure 2 The figures show the effect of Examples 1-2 and Comparative Examples 1-8 in suppressing the generation of hydrogen sulfide in the drainage system. Among them, (a) represents Examples 1-2, (b) represents Comparative Examples 1-4, and (c) represents Comparative Examples 5-8.
[0021] Figure 3This is a schematic diagram of the experimental setup for the embodiments and comparative examples. Detailed Implementation
[0022] The technical solution of the present invention will be clearly and completely described below with reference to the data in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.
[0023] It should be noted that the technical terms used in this invention are for the purpose of describing specific embodiments only and are not intended to limit the scope of protection of this invention. Unless otherwise specified, all raw materials, reagents, instruments and equipment used in the following embodiments of this invention can be purchased commercially or prepared by existing methods. Sodium nitroprusside, SNP.
[0024] Currently, source inhibition of sulfide formation has become the mainstream technology for controlling hydrogen sulfide pollution in drainage systems. However, the biofilm barrier prevents SRBs from direct contact with the chemicals. This barrier significantly reduces the apparent sensitivity of SRBs within the biofilm, forcing a substantial increase in dosage and drastically increasing operating costs. Furthermore, most current agents for inhibiting hydrogen sulfide production (such as glutaraldehyde and molybdate) have significant environmental impacts.
[0025] To address the problems existing in the prior art, the present invention provides a composition for suppressing the generation of hydrogen sulfide in a drainage system, comprising an NO donor and tetramethylolphosphine sulfate; wherein the mass ratio of the NO donor to tetramethylolphosphine sulfate is 1:2~2.5.
[0026] Based on quorum sensing (QS) theory, this invention proposes for the first time to enhance the effect of THPS in inhibiting SRB hydrogen sulfide production by inducing the dispersion of sulfate-reducing bacteria biofilm with NO, thus achieving high efficiency, economy, and environmental friendliness. Specifically, trace amounts of NO (pmol to nmol) can inhibit biofilm growth and disperse mature biofilm; NO, as a QS signaling molecule interfering agent, reduces EPS synthesis by lowering the level of the signaling molecule c-di-GMP (inhibiting DGC enzyme or activating PDE enzyme), thus dispersing the biofilm and weakening the protective barrier of SRB; THPS, due to its environmental safety and good biodegradability, can serve as an environmentally friendly inhibitor for effectively suppressing hydrogen sulfide production in drainage systems. The mechanism of this invention's composition for inhibiting hydrogen sulfide production in drainage systems is illustrated in the diagram below. Figure 1 As shown.
[0027] To enable those skilled in the art to more clearly understand the technical solution of the present invention, the following will provide a detailed description in conjunction with specific embodiments:
[0028] From the sulfate reduction system reactor, a 12cm section of fiber packing material with a stable sulfate-reducing bacterial biofilm was taken out and placed in a 250mL Erlenmeyer flask. 200mL of artificially prepared water simulating domestic sewage was added, and nitrogen gas was introduced to remove dissolved oxygen from the sewage. The flask was then immediately sealed with a sealed bag, wrapped in aluminum foil to protect it from light, and placed in a constant temperature shaker at 30℃ and 100rpm for 24 hours of dark incubation. After the incubation period, all the sewage in the Erlenmeyer flask was drained, and the concentration of sulfides in the effluent was monitored. Then, 200mL of fresh artificially prepared water was added again, and the next 24-hour batch incubation was initiated. This process was repeated until the sulfide concentration in the effluent stabilized at 50mg / L, at which point a hydrogen sulfide inhibition experiment was conducted.
[0029] Example 1
[0030] A method for suppressing hydrogen sulfide generation in a drainage system, the experimental setup of which is as follows: Figure 3 As shown, it includes the following steps:
[0031] Add 10 mg / L of SNP and 20 mg / L of THPS sequentially to a conical flask containing 50 mg / L of sulfide in the effluent. Add artificially prepared water to a final volume of 200 mL. Purge the flask with nitrogen to remove dissolved oxygen from the wastewater. Immediately seal the flask with a sealed bag, wrap it in aluminum foil to protect it from light, and incubate it in the dark for 24 hours in a constant temperature shaker at 30°C and 100 rpm. Measure the sulfide concentration in the water immediately after the incubation period.
[0032] Test results are as follows Figure 2 As shown in Figure (c), the concentration of sulfide in the effluent is 4 mg / L.
[0033] Example 2
[0034] A method for suppressing hydrogen sulfide generation in a drainage system includes the following steps:
[0035] Add 10 mg / L of SNP and 25 mg / L of THPS sequentially to a conical flask containing 50 mg / L of sulfide in the effluent. Add artificially prepared water to a final volume of 200 mL. Purge the flask with nitrogen to remove dissolved oxygen from the wastewater. Immediately seal the flask with a sealed bag, wrap it in aluminum foil to protect it from light, and incubate it in the dark for 24 hours in a constant temperature shaker at 30°C and 100 rpm. Measure the sulfide concentration in the water immediately after the incubation period.
[0036] Test results are as follows Figure 2 As shown in Figure (c), the concentration of sulfide in the effluent was 0 mg / L. The addition of 10 mg / L SNP and 25 mg / L THPS could completely inhibit the formation of sulfide.
[0037] Example 3
[0038] A method for suppressing hydrogen sulfide generation in a drainage system, which is the same as the steps in Example 2, except that the incubation temperature is changed from 30°C to 10°C, includes the following steps:
[0039] Add 10 mg / L of SNP and 25 mg / L of THPS sequentially to a conical flask containing 50 mg / L of sulfide in the effluent. Add artificially prepared water to a final volume of 200 mL. Purge the flask with nitrogen to remove dissolved oxygen from the wastewater. Immediately seal the flask with a sealed bag, wrap it in aluminum foil to protect it from light, and incubate it in the dark for 24 hours in a constant temperature shaker at 10°C and 100 rpm. Measure the sulfide concentration in the water immediately after the incubation period.
[0040] Comparative Example 1
[0041] A method for suppressing hydrogen sulfide generation in a drainage system, which is the same as the steps in Example 1, except that sodium nitroprusside is added separately, includes the following steps:
[0042] Add 10 mg / L of SNP to a conical flask containing 50 mg / L of sulfide in the effluent, add artificially prepared water to a final volume of 200 mL, purge with nitrogen to remove dissolved oxygen from the wastewater, then immediately seal the flask with a sealed bag, wrap it in aluminum foil to protect it from light, and incubate it in the dark for 24 hours in a constant temperature shaker at 30°C and 100 rpm. Immediately after the incubation period, measure the sulfide concentration in the water.
[0043] Test results are as follows Figure 2 As shown in Figure (a), the concentration of sulfide in the effluent is 42 mg / L.
[0044] Comparative Example 2
[0045] A method for inhibiting hydrogen sulfide generation in a drainage system, which is the same as the steps in Comparative Example 1, except that the dosage of sodium nitroprusside is replaced by 40 mg / L instead of 10 mg / L, includes the following steps:
[0046] Add 40 mg / L of SNP to a conical flask containing 50 mg / L of sulfide in the effluent, add artificially prepared water to a final volume of 200 mL, purge with nitrogen to remove dissolved oxygen from the wastewater, then immediately seal the flask with a sealed bag, wrap it in aluminum foil to protect it from light, and incubate it in the dark for 24 hours in a constant temperature shaker at 30°C and 100 rpm. Immediately after the incubation period, measure the sulfide concentration in the water.
[0047] Test results are as follows Figure 2 As shown in Figure (a), the concentration of sulfide in the effluent is 19 mg / L.
[0048] Comparative Example 3
[0049] A method for inhibiting hydrogen sulfide generation in a drainage system, which is the same as the steps in Comparative Example 1, except that the dosage of sodium nitroprusside is replaced by 80 mg / L instead of 10 mg / L, includes the following steps:
[0050] Add 80 mg / L of SNP to an Erlenmeyer flask containing 50 mg / L of sulfide in the effluent, add artificially prepared water to a final volume of 200 mL, purge with nitrogen to remove dissolved oxygen from the wastewater, then immediately seal the flask with a sealed bag, wrap it in aluminum foil to protect it from light, and incubate it in the dark for 24 hours in a constant temperature shaker at 30°C and 100 rpm. Immediately after the incubation period, measure the sulfide concentration in the water.
[0051] Test results are as follows Figure 2 As shown in Figure (a), the concentration of sulfide in the effluent is 5 mg / L.
[0052] Comparative Example 4
[0053] A method for inhibiting hydrogen sulfide generation in a drainage system, which is the same as the steps in Comparative Example 1, except that the dosage of sodium nitroprusside is replaced by 90 mg / L instead of 10 mg / L, includes the following steps:
[0054] Add 90 mg / L of SNP to a conical flask containing 50 mg / L of sulfide in the effluent, add artificially prepared water to a final volume of 200 mL, purge with nitrogen to remove dissolved oxygen from the wastewater, then immediately seal the flask with a sealed bag, wrap it in aluminum foil to protect it from light, and incubate it in the dark for 24 hours in a constant temperature shaker at 30°C and 100 rpm. Immediately after the incubation period, measure the sulfide concentration in the water.
[0055] Test results are as follows Figure 2 As shown in Figure (a), the concentration of sulfide in the effluent is 0 mg / L, which can completely suppress the generation of sulfide.
[0056] Comparative Example 5
[0057] A method for suppressing hydrogen sulfide generation in a drainage system, which is the same as the steps in Example 1, except that tetramethylolphosphine sulfate is added separately, includes the following steps:
[0058] Add 20 mg / L of THPS to an Erlenmeyer flask containing 50 mg / L of sulfide in the effluent, add artificially prepared water to a final volume of 200 mL, purge with nitrogen to remove dissolved oxygen from the wastewater, then immediately seal the flask with a sealed bag, wrap it in aluminum foil to protect it from light, and incubate it in the dark for 24 hours in a constant temperature shaker at 30°C and 100 rpm. Immediately after the incubation period, measure the sulfide concentration in the water.
[0059] Test results are as follows Figure 2 As shown in Figure (b), the concentration of sulfide in the effluent is 39 mg / L.
[0060] Comparative Example 6
[0061] A method for inhibiting hydrogen sulfide generation in a drainage system, identical to that of Comparative Example 5, except that the dosage of tetramethylolphosphine sulfate is changed from 20 mg / L to 80 mg / L, comprising the following steps:
[0062] Add 80 mg / L of THPS to an Erlenmeyer flask containing 50 mg / L of sulfide in the effluent, add artificially prepared water to a final volume of 200 mL, purge with nitrogen to remove dissolved oxygen from the wastewater, then immediately seal the flask with a sealed bag, wrap it in aluminum foil to protect it from light, and incubate it in the dark for 24 hours in a constant temperature shaker at 30°C and 100 rpm. Immediately after the incubation period, measure the sulfide concentration in the water.
[0063] Test results are as follows Figure 2 As shown in Figure (b), the concentration of sulfide in the effluent is 14 mg / L.
[0064] Comparative Example 7
[0065] A method for inhibiting hydrogen sulfide generation in a drainage system, identical to that of Comparative Example 5, except that the dosage of tetramethylolphosphine sulfate is changed from 20 mg / L to 100 mg / L, comprising the following steps:
[0066] Add 100 mg / L of THPS to an Erlenmeyer flask containing 50 mg / L of sulfide in the effluent, add artificially prepared water to a final volume of 200 mL, purge with nitrogen to remove dissolved oxygen from the wastewater, then immediately seal the flask with a sealed bag, wrap it in aluminum foil to protect it from light, and incubate it in the dark for 24 hours in a constant temperature shaker at 30°C and 100 rpm. Immediately after the incubation period, measure the sulfide concentration in the water.
[0067] Test results are as follows Figure 2 As shown in Figure (b), the concentration of sulfide in the effluent is 8 mg / L.
[0068] Comparative Example 8
[0069] A method for inhibiting hydrogen sulfide generation in a drainage system, identical to that of Comparative Example 5, except that the dosage of tetramethylolphosphine sulfate is changed from 20 mg / L to 110 mg / L, comprising the following steps:
[0070] Add 110 mg / L of THPS to an Erlenmeyer flask containing 50 mg / L of sulfide in the effluent, then add artificially prepared water to a final volume of 200 mL. Purge the flask with nitrogen to remove dissolved oxygen from the wastewater. Immediately seal the flask with a sealed bag, wrap it in aluminum foil to protect it from light, and incubate it in the dark for 24 hours at 30°C and 100 rpm in a constant temperature shaker. Measure the sulfide concentration in the water immediately after the incubation period.
[0071] Test results are as follows Figure 2 As shown in Figure (b), the concentration of sulfides in the effluent is 0 mg / L, which can completely suppress the formation of sulfides.
[0072] like Figure 2 As shown in Figure (a), adding 90 mg / L sodium nitroprusside alone can completely inhibit the formation of sulfides; Figure 2 As shown in Figure (b), adding 110 mg / L of THPS alone can completely inhibit the formation of sulfides, indicating that the addition of SNP and THPS has a good inhibitory effect on the formation of sulfides. However, a very high addition amount is required, which increases the cost and affects industrial application. This application uses a NO donor and tetramethylolphosphine sulfate to obtain a composition for inhibiting the formation of hydrogen sulfide in drainage systems. By utilizing the synergistic effect of the two, complete inhibition of sulfides is achieved under low addition conditions, overcoming the cost problem. Figure 2 As shown in Figure (c), the combined addition of 10 mg / L SNP and 25 mg / L THPS can completely inhibit the formation of sulfides.
[0073] The fractional inhibitory concentration index (FICI) is calculated as shown in equation (1). FICI < 1 indicates that the two drugs have a synergistic effect, and FICI > 2 indicates that they have an antagonistic effect.
[0074] (1).
[0075] In the formula MIC(A / B)—A Pharmaceuticals and B The optimal inhibitory effect is achieved by combining different medications. A Dosage of the drug (mg / L); MIC(B / A)—A Pharmaceuticals and B The optimal inhibitory effect is achieved by combining different medications. B Dosage of the drug (mg / L); MIC(A)—A The dosage (mg / L) required to achieve the best inhibitory effect when the drug is added alone. MIC(B)—B The dosage (mg / L) required to achieve the best inhibitory effect when the drug is added alone.
[0076] Compared with Comparative Examples 1 and 2, the addition of SNP (NO donor) significantly reduced the amount of THPS added. The fractional inhibition concentration index of the combined addition of SNP and THPS was 0.34, indicating that the combination of NO and THPS had a strong synergistic effect on inhibiting the formation of sulfides.
[0077] It should be noted that when numerical ranges are involved in this invention, it should be understood that both endpoints of each numerical range, as well as any value between the two endpoints, can be selected. Since the steps and methods used are the same as in the embodiments, preferred embodiments are described here to avoid redundancy. Although preferred embodiments of the invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this invention.
Claims
1. A method of applying a composition for suppressing hydrogen sulfide generation in a drainage system, characterized in that, A combination of sodium nitroprusside and tetramethyl phosphonic acid was used as an inhibitor. The inhibitor was added to a drainage system containing a sulfate-reducing bacterial biofilm, and then cultured. The mass ratio of sodium nitroprusside to tetrahydroxymethylphosphoric acid is 1:2.
5.
2. The application method according to claim 1, characterized in that, The cultivation conditions were as follows: cultured in a dark anaerobic environment at 10℃~30℃ for 24 hours.
3. The application method according to claim 1, characterized in that, The mass ratio of NO donor to sulfides in the drainage system is 10:50, and the mass ratio of tetrahydroxymethylphosphonic acid sulfate to sulfides in the drainage system is 20~25:50.