Sewage treatment method based on sulfate reduction and endogenous sulfur autotrophic denitrification

Abstract

The invention discloses a sewage treatment method based on sulfate reduction and endogenous sulfur autotrophic denitrification, which comprises the following steps: sewage enters an anoxic tank, sodium sulfate is added, sulfate reducing bacteria take sulfate ions as final electron acceptors for organic matter degradation, phosphorus absorption is realized, ammonium ions are oxidized into nitrate ions, and the nitrate ions are subjected to secondary denitrification. The sulfate ions are reduced into sulfur anions; effluent of the anoxic tank enters a primary sedimentation tank to realize mud-water separation, effluent containing sulfur anions and nitrate ions is discharged into a sulfur autotrophic denitrification filter tank, and phosphorus-containing sludge is discharged into the sulfur autotrophic denitrification filter tank after being subjected to phosphorus removal through an anaerobic phosphorus discharge tank and a secondary sedimentation tank; the sulfur anions reduce the nitrate ions into nitrogen and form elemental sulfur precipitates, and the residual sulfur anions are removed by the biological aerated filter and then discharged. The sewage treatment method disclosed by the invention is low in oxygen consumption and less in residual sludge, and the sewage treatment cost is greatly reduced; meanwhile, heavy metal in the sewage is effectively removed, phosphorus in the sewage is converted into fertilizer, and effective treatment of phosphorus is achieved.

Description

Technical Field

[0001] The invention relates to the technical field of sewage treatment, and in particular to a sewage treatment method based on sulfate reduction and endogenous sulfur autotrophic denitrification. Background Art

[0002] Traditional municipal sewage is generally treated by activated sludge method or biofilm method. Among them, activated sludge method is widely used, mainly used in large biological sewage treatment plants and some industrial water sewage treatment plants with relatively large sewage volumes. Its advantages are stability, reliability and mature technology. Biofilm method is mainly used to treat small-volume urban domestic sewage, landscape water and small-volume industrial wastewater.

[0003] However, the above process has the following four basic problems:

[0004] (1) Oxygen is difficult to dissolve. In large-scale process production, the dissolved oxygen in sewage is generally maintained at 2 mg / L. The oxygen utilization rate is generally around 10%, and the larger the scale of sewage treatment, the more air needs to be blown in, resulting in higher power consumption. At present, the power consumption of water plants using the activated sludge process is mostly 0.2-0.3kW·h / m 3 The power consumption per ton of water by the biofilm method is higher, about 0.5kW·h / m 3 , the energy consumption is relatively large, and the cost is difficult to reduce. In addition, the violent stirring brings about nonlinear changes in water flow lines, excessive mechanical shear force and other problems, which in turn increases the complexity of sewage operation.

[0005] (2) Conventional aerobic treatment produces a large amount of sludge, which is difficult to dispose of and has high costs. The sludge production accounts for about 0.3%-0.5% of the treated water volume (based on a water content of 97%). The main organic matter in the sludge is difficult-to-treat microbial cells. It also contains a large amount of toxic and harmful substances, such as parasite eggs, pathogenic microorganisms, bacteria, synthetic organic matter and heavy metal ions. Of the total construction costs of a sewage treatment plant, the cost of sludge treatment accounts for about 20% to 50%, or even 70%. The residual sludge is essentially the energy in the COD in the sewage transferred to the cells, and covered with a stable cell wall with a structure mainly composed of peptidoglycan. In contrast, the anaerobic treatment method transfers the energy in the COD of the sewage to methane, so the amount of sludge in the anaerobic process is very small. Therefore, it is necessary to find a way to transfer part of the energy in the COD in the sewage to other parts, thereby reducing the production of residual sludge.

[0006] (3) The COD energy in sewage is certain, even relatively excessive, but because the energy is basically transferred to the residual sludge for anabolism, the carbon source for denitrification is insufficient. In terms of the process, it is first heterotrophic metabolism to reduce the BOD to about 20 mg / L, and then chemoautotrophy is carried out to oxidize ammonium ions to nitrate ions. The subsequent denitrification lacks the necessary carbon source. Although it can be compensated by pre-denitrification, an external carbon source is still required. Although some sewage treatment plants have post-sulfur autotrophic denitrification filters to enhance the denitrification function, due to the added characteristics of sulfur-containing fillers, the nitrate ions are always treated in excess in the local area of ​​the reaction interface, making the sulfur element easily over-oxidized into sulfate ions, making the effluent acidic.

[0007] (4) The phosphorus element in the sewage is not properly handled. On the one hand, the phosphorus metabolic pathway, from phosphate ions in the sewage to intracellular polyphosphates, is driven by ATP formed by the internal electron respiratory chain of bacteria. Obviously, the phosphorus accumulation capacity of a single bacterium is limited, and the sludge concentration in the traditional process is only about 4g / L, which makes the volume load of the system low and the phosphorus accumulation efficiency reduced; on the other hand, only a small part of the phosphorus-containing sludge formed in the traditional aerobic tank is discharged in the form of residual sludge, and most of the adsorbed phosphorus is released back into the sewage, further reducing the phosphorus removal capacity of the system. In the prior art, a flocculation sedimentation tank is set up, PAC and PAM are added for chemical phosphorus removal, and the residual sludge or chemical sludge is landfilled, which further causes the phosphorus content of the leachate to exceed the standard, and the phosphorus is not finally stabilized. Summary of the invention

[0008] In view of the deficiencies in the prior art, the present invention provides a sewage treatment method based on sulfate reduction and endogenous sulfur autotrophic denitrification, starting from the electron respiratory chain inside bacteria, domesticating sulfate-reducing bacteria, using sulfate ions instead of oxygen as the final electron acceptor, without changing the basic substrate level phosphorylation and citric acid cycle in bacteria, without affecting the metabolic standards of organic matter, without affecting the total ATP production, part of the energy is transferred to sulfur anions, thereby laying a foundation for sludge reduction and subsequent endogenous sulfur autotrophic denitrification.

[0009] In order to solve the above technical problems, the present invention provides a sewage treatment method based on sulfate reduction and endogenous sulfur autotrophic denitrification, comprising the following steps:

[0010] S1. Municipal sewage enters the anoxic tank, and sodium sulfate and sulfate-reducing bacteria (SRB) are added. Sulfate-reducing bacteria use sulfate ions as the final electron acceptor to degrade COD, absorb phosphorus, and oxidize ammonium ions to nitrate ions. Sulfate ions are reduced to sulfur anions at this stage.

[0011] S2, the effluent from the anoxic tank enters a sedimentation tank to separate mud and water, the effluent containing sulfur anions and nitrate ions is discharged into the sulfur autotrophic denitrification filter, and the phosphorus-containing sludge is discharged into the anaerobic phosphorus release tank;

[0012] The anaerobic phosphorus release tank introduces municipal raw water to wash and remove the remaining sulfate ions in the phosphorus-containing sludge to form an anaerobic environment, supplement COD to achieve the release of phosphorus in the sludge, and the supernatant containing phosphate ions is discharged into the secondary sedimentation tank, and the sludge after phosphorus release is returned to the anoxic tank;

[0013] The secondary sedimentation tank is added with lime (Ca(OH) 2 ), converting phosphorus phosphate ions in sewage into hydroxy calcium phosphate precipitation to form fertilizer, and the supernatant is discharged into the sulfur autotrophic denitrification filter;

[0014] S3, the sulfur anions in the sulfur autotrophic denitrification filter reduce nitrate ions to nitrogen gas and form sulfur element precipitation;

[0015] S4. The effluent from the sulfur autotrophic denitrification filter enters the aerated biological filter to oxidize the remaining sulfur anions into sulfur elemental precipitation, and the effluent meets the discharge standards.

[0016] Furthermore, in S1, the sulfate-reducing bacteria uses sulfate ions as the final electron acceptor to degrade COD, specifically: the sulfate-reducing bacteria uses sulfate ions as the final electron acceptor to complete the complete citric acid cycle to produce ATP.

[0017] Furthermore, in S1, the absorption of phosphorus is specifically achieved as follows: the ATP generated by the citric acid cycle absorbs phosphorus in the sewage into the body and synthesizes polyphosphate to achieve ATP storage and polymerization of phosphate in the sewage.

[0018] Furthermore, in S2, the supplementation of COD to achieve the release of phosphorus in the sludge is specifically as follows: in an anaerobic environment containing COD, the polyphosphate decomposes to produce ATP and releases phosphate ions.

[0019] The core of biological treatment, sludge itself is an independent and open system. Its independence is manifested in that various microorganisms inside it form a unified and organic combination; its openness is manifested in that the sludge system is deeply affected by changes in the external environment. The sludge system itself has the system characteristics of general biological systems: a high degree of integration of material flow, energy flow and information flow.

[0020] The material flow of biological systems is the material basis of biological treatment. The degradation of original molecules in raw water into various small molecules is the material flow of biological systems.

[0021] The energy flow of biological treatment system is the driving force of biological treatment. The reason why conventional anaerobic treatment is slow is that it only stays in substrate level phosphorylation. In essence, one functional group oxidizes another functional group, and the energy utilization rate is very low. One glucose molecule undergoes glycolysis reaction and can only generate 2 ATPs. Therefore, most of the energy in the raw water flows into methane, and very little energy flows into the sludge. Therefore, the entire sludge system is very weak and inefficient. The addition of sulfate can solve this problem. In the electron transport chain, sulfate ions and oxygen are in the same position. In the absence of molecular oxygen, sulfate-reducing bacteria use sulfate ions instead of oxygen as the final electron acceptor. In this way, the sludge can obtain the same energy ratio as aerobic treatment without aeration. At the same time, the two have exactly the same substrate level phosphorylation, citric acid cycle and basically the same cellular electron respiratory chain. One glucose molecule can be completely decomposed to form 30 ATPs.

[0022] For aerobic treatment, by increasing the aeration volume, the treatment rate can be increased and the effluent quality can be improved. The essential reason is to increase the flow rate of energy flow. In other words, it increases the power of the sludge system. However, due to the cost and the physical and chemical properties of oxygen, it is difficult to increase the dissolved oxygen level. However, sodium sulfate is easily soluble and can increase the equivalent dissolved oxygen level in water to 1000 mg / L, which completely frees the biological treatment system from the limitation of dissolved oxygen. In S1, the sludge concentration in the anoxic tank is as high as 35-45 g / L, close to the anaerobic sludge concentration, which is nearly 10 times higher than that of the traditional aerobic system, greatly improving the volume load of the system, thereby reducing the volume of the reaction tank, and ultimately reducing the corresponding infrastructure costs; at the same time, more bacteria will adsorb the phosphate ions in the unit volume of sewage, and all the phosphorus-containing sludge can enter the anaerobic phosphorus release unit (rather than the traditional AAO process, where only part of the sludge discharges phosphorus in the form of residual sludge), fundamentally improving the biological phosphorus removal capacity of the system; and due to the high sludge concentration, the phosphorus content of the supernatant of the anaerobic phosphorus release tank can be close to that of the supernatant of the traditional gravity thickening tank, which can not only reduce the amount of lime used, but also the fertilizer formed after reaction with lime has a higher phosphorus content.

[0023] The information flow of biological treatment system is the soul of biological treatment system. The main reason why conventional anaerobic treatment is difficult to control and run smoothly is that it is difficult to coordinate the growth and metabolic balance between hydrolytic acidifying bacteria, gas-producing bacteria and methanogenic bacteria (archaea). Sulfate-reducing bacteria are more evolved bacteria with mitochondria in their cells, which can directly complete the conversion process from macromolecules to carbon dioxide. The information flow is relatively simple. In addition, due to the inhibition of miscellaneous bacteria by hydrogen sulfide, the information flow of sulfate-reducing bacteria treatment system is highly stable and self-controlled. The metabolic process of sulfate-reducing bacteria is divided into three steps, namely catabolism, electron transfer and oxidation. In the first step of catabolism, the decomposition of organic carbon source is carried out in the absence of molecular oxygen, and a small amount of ATP is produced through substrate level phosphorylation; in the second step of electron transfer, the high-energy electrons released in the previous process are transferred step by step through the inherent electron transfer chain in sulfate-reducing bacteria, producing a large amount of ATP; in the final oxidation process, electrons are transferred to the oxidized sulfur element and reduced to S 2- At this time, a certain amount of ATP is needed to provide energy. Sulfate, as the final electron acceptor of sulfate-reducing bacteria, undergoes a series of reactions in the bacteria and is eventually reduced to S 2- Excreted from the body.

[0024] The water ion solubility product of sulfur anions and heavy metal ions is very small. Therefore, when sulfate-reducing bacteria treat sewage, their metabolism produces sulfur anions, which can effectively precipitate heavy metal ions in sewage, making the concentration of heavy metal ions in sewage reach 1*10 -10 Below mg / L.

[0025] Due to the generation of sulfur anions, part of the ATP used for sludge appreciation is consumed, which reduces the sludge yield coefficient and reduces the generation of excess sludge from the root.

[0026] In traditional AAO sewage treatment, BOD must be metabolized to below 20 mg / L before chemoautotrophy with ammonium ions can be started, so that ammonium ions are oxidized to nitrate ions, which makes the subsequent denitrification lack of carbon source. In this process, due to the generation of sulfur anions, sulfur autotrophic denitrification can be started in the subsequent denitrification unit, and because the sulfur anions are evenly distributed in the sewage at this time and are in excess, the sulfur anions will be oxidized into sulfur and separated during denitrification, and will not be further oxidized into sulfate ions to acidify the effluent. This solves the problem of high reagent costs and easy acidification of effluent in conventional sulfur autotrophic denitrification filters.

[0027] Since the endogenous sulfur autotrophic denitrification filter is a post-denitrification, it will not compete with the anaerobic phosphorus release unit for carbon sources. In addition, due to the low sludge yield coefficient, the sludge age is longer than that of the conventional system, which can increase the proportion of nitrifying bacteria and denitrifying bacteria with longer sludge age in the sludge, thereby further improving the denitrification effect of the system.

[0028] Sulfate oxidizes organic matter, changing its own valence from hexavalent to divalent, gaining 8 electrons. When separated from the system, it only needs to gain 2 electrons to become elemental sulfur, which can reduce the aeration volume by 75%. Since the oxygen utilization rate is generally only about 10%, the aeration volume can actually be reduced further, which can not only reduce power consumption but also reduce aerosol pollution.

[0029] Furthermore, in S2, the anaerobic phosphate release pond is introduced with municipal raw water for washing, and the washing water produced is returned to the anoxic pond.

[0030] Furthermore, in S1, the dosage of the sodium sulfate is 220-230 mg sodium sulfate for every 100 mg COD.

[0031] Furthermore, in S2, the amount of lime added is 35-45 mg lime / m 3 Sewage.

[0032] The second aspect of the present invention provides a sewage treatment device based on sulfate reduction and endogenous sulfur autotrophic denitrification, which is used to implement the method described in the first aspect, comprising an anoxic tank, a settling tank, a sulfur autotrophic denitrification filter and an aerated biological filter connected in sequence, the sludge outlet of the first settling tank is connected to an anaerobic phosphate release tank, the water outlet of the anaerobic phosphate release tank is connected to a second settling tank, and the water outlet of the second settling tank is connected to the sulfur autotrophic denitrification filter.

[0033] Furthermore, the anaerobic phosphorus release pond is connected to the anoxic pond through a reflux pipe.

[0034] Beneficial effects of the present invention:

[0035] The present invention starts from the electron respiratory chain inside bacteria, domesticates sulfate-reducing bacteria, uses sulfate ions instead of oxygen as the final electron acceptor, does not change the basic substrate level phosphorylation and citric acid cycle in bacteria, does not affect the metabolic standards of organic matter, and does not affect the total ATP production. It transfers part of the energy to sulfur anions, laying a foundation for sludge reduction and subsequent endogenous sulfur autotrophic denitrification.

[0036] The invention has low oxygen consumption and little residual sludge, thus greatly reducing the sewage treatment cost; at the same time, it effectively removes heavy metals in sewage and converts phosphorus in sewage into fertilizer, thus realizing effective phosphorus treatment. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the technical solution of the present invention, the drawings required for use in the embodiments are briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0038] Figure 1 The present invention is a flow chart of a sewage treatment method based on sulfate reduction and endogenous sulfur autotrophic denitrification. DETAILED DESCRIPTION

[0039] The technical solution of the present invention will be described clearly and completely below in conjunction with the specific embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0040] Reference Figure 1 As shown, an embodiment of the present invention provides a sewage treatment method based on sulfate reduction and endogenous sulfur autotrophic denitrification, comprising the following steps:

[0041] S1. Municipal sewage enters the anoxic tank, and sodium sulfate and sulfate-reducing bacteria are added. Sulfate-reducing bacteria use sulfate ions as the final electron acceptor to complete the complete citric acid cycle to produce ATP to achieve COD degradation. The generated ATP absorbs phosphorus in the sewage into the body and synthesizes polyphosphate to achieve ATP storage and polymerization of phosphate in sewage, and oxidizes ammonium ions to nitrate ions. Sulfate ions are reduced to sulfur anions at this stage;

[0042] S2, the effluent from the anoxic tank enters a sedimentation tank to separate mud and water, the effluent containing sulfur anions and nitrate ions is discharged into the sulfur autotrophic denitrification filter, and the phosphorus-containing sludge is discharged into the anaerobic phosphorus release tank;

[0043] The anaerobic phosphorus release tank introduces municipal raw water to wash and remove the remaining sulfate ions in the phosphorus-containing sludge to form an anaerobic environment and replenish COD. In the anaerobic environment containing COD, the polyphosphate decomposes to produce ATP and releases phosphate ions. The supernatant containing phosphate ions is discharged into the secondary sedimentation tank, and the sludge after releasing phosphorus is returned to the anoxic tank;

[0044] Lime is added to the secondary sedimentation tank to convert phosphorus phosphate ions in the sewage into hydroxy calcium phosphate precipitation to form fertilizer, and the supernatant is discharged into the sulfur autotrophic denitrification filter tank;

[0045] S3, the sulfur anions in the sulfur autotrophic denitrification filter reduce nitrate ions to nitrogen gas and form sulfur element precipitation;

[0046] S4. The effluent from the sulfur autotrophic denitrification filter enters the aerated biological filter to oxidize the remaining sulfur anions into sulfur elemental precipitation, and the effluent meets the discharge standards.

[0047] As a specific example, in S1, the dosage of sodium sulfate is 222 mg for every 100 mg COD. Sodium sulfate is easily soluble and can increase the equivalent dissolved oxygen level in water to 1000 mg / L, so that the biological treatment system is completely free from the limitation of dissolved oxygen. In S1, the sludge concentration in the anoxic tank is as high as 40 g / L. The sludge can degrade COD from 400 mg / L to 10 mg / L in 4 hours. Under anoxic conditions, sulfate-reducing bacteria oxidize 96% of ammonia nitrogen into nitrate ions and sulfate is reduced to sulfur anions. Due to the generation of sulfur anions, part of the ATP used for sludge value-added is consumed, reducing the residual sludge output by 20%. At the same time, the water ion solubility product of sulfur anions and heavy metal ions is very small, which effectively precipitates heavy metal ions in sewage, reducing the concentration of heavy metal ions in sewage to 1*10 -10 mg / L.

[0048] As a specific example, in S2, the amount of lime added is 40 mg lime / m 3 The released phosphate ions are converted into phosphorus-containing fertilizers, while the phosphorus content in the sewage is reduced from 4 mg / L to 0.1 mg / L.

[0049] As a specific example, in S2, the anaerobic phosphate release pond is introduced with municipal raw water for washing, and the washing water produced is returned to the anoxic pond.

[0050] Another embodiment provides a sewage treatment device based on sulfate reduction and endogenous sulfur autotrophic denitrification, the device structure is referenced Figure 1 , including an anoxic tank, a settling tank, a sulfur autotrophic denitrification filter and an aerated biological filter connected in sequence, the sludge outlet of the first settling tank is connected to the anaerobic phosphate release tank, the water outlet of the anaerobic phosphate release tank is connected to the second settling tank, the water outlet of the second settling tank is connected to the sulfur autotrophic denitrification filter, and the anaerobic phosphate release tank is connected to the anoxic tank through a reflux pipe.

[0051] In summary, the present invention starts from the electron respiratory chain inside bacteria, domesticates sulfate-reducing bacteria, uses sulfate ions instead of oxygen as the final electron acceptor, does not change the basic substrate level phosphorylation and citric acid cycle in bacteria, does not affect the metabolic standards of organic matter, and does not affect the total ATP production. On the basis of transferring part of the energy to sulfur anions, it lays a foundation for sludge reduction and subsequent endogenous sulfur autotrophic denitrification; the oxygen consumption is low and the residual sludge is small, which greatly reduces the cost of sewage treatment; at the same time, it effectively removes heavy metals in sewage and converts phosphorus in sewage into fertilizer, thereby realizing effective phosphorus treatment.

[0052] The present invention has been described in detail above in conjunction with specific implementations and exemplary examples, but these descriptions cannot be understood as limiting the present invention. Those skilled in the art understand that, without departing from the spirit and scope of the present invention, a variety of equivalent substitutions, modifications or improvements may be made to the technical solution of the present invention and its implementation methods, all of which fall within the scope of the present invention. The scope of protection of the present invention shall be subject to the attached claims.

Claims

1. A sewage treatment method based on sulfate reduction and endogenous sulfur autotrophic denitrification, characterized in that: The steps include: S1. Municipal sewage enters the anoxic tank, sodium sulfate is added, and sulfate-reducing bacteria use sulfate ions as the final electron acceptor to degrade COD, absorb phosphorus, and oxidize ammonium ions to nitrate ions. Sulfate ions are reduced to sulfur anions at this stage; S2, the effluent from the anoxic tank enters a sedimentation tank to separate mud and water, the effluent containing sulfur anions and nitrate ions is discharged into the sulfur autotrophic denitrification filter, and the phosphorus-containing sludge is discharged into the anaerobic phosphorus release tank; The anaerobic phosphate release tank introduces municipal raw water to wash and remove the remaining sulfate ions in the phosphorus-containing sludge to form an anaerobic environment, supplement COD to release phosphorus in the sludge, and the supernatant containing phosphate ions is discharged into the secondary sedimentation tank; Lime is added to the secondary sedimentation tank to convert phosphorus phosphate ions in the sewage into hydroxy calcium phosphate precipitation, and the supernatant is discharged into the sulfur autotrophic denitrification filter; S3, the sulfur anions in the sulfur autotrophic denitrification filter reduce nitrate ions to nitrogen gas and form sulfur precipitation; S4. The effluent from the sulfur autotrophic denitrification filter enters the aerated biological filter to oxidize the remaining sulfur anions into sulfur elemental precipitation, and the effluent meets the discharge standards.

2. The sewage treatment method based on sulfate reduction and endogenous sulfur autotrophic denitrification according to claim 1, characterized in that: In S1, the sulfate-reducing bacteria uses sulfate ions as the final electron acceptor to degrade COD. Specifically, the sulfate-reducing bacteria uses sulfate ions as the final electron acceptor to complete the complete citric acid cycle and produce ATP.

3. The sewage treatment method based on sulfate reduction and endogenous sulfur autotrophic denitrification according to claim 2, characterized in that: In S1, the absorption of phosphorus is specifically achieved as follows: the ATP generated by the citric acid cycle absorbs phosphorus in the sewage into the body and synthesizes polyphosphate to achieve ATP storage and polymerization of phosphate in the sewage.

4. The sewage treatment method based on sulfate reduction and endogenous sulfur autotrophic denitrification according to claim 3, characterized in that: In S2, the supplementation of COD to achieve the release of phosphorus in the sludge is specifically as follows: in an anaerobic environment containing COD, the polyphosphate decomposes to produce ATP and releases phosphate ions.

5. The sewage treatment method based on sulfate reduction and endogenous sulfur autotrophic denitrification according to claim 1, characterized in that: In S2, the anaerobic phosphate release pond is introduced with municipal raw water for washing, and the washing water produced is returned to the anoxic pond.

6. The sewage treatment method based on sulfate reduction and endogenous sulfur autotrophic denitrification according to claim 1, characterized in that: In S1, the dosage of sodium sulfate is 220-230 mg for every 100 mg COD.

7. The sewage treatment method based on sulfate reduction and endogenous sulfur autotrophic denitrification according to claim 1, characterized in that: In S1, the sludge concentration in the anoxic tank is 35-45g / L.

8. The sewage treatment method based on sulfate reduction and endogenous sulfur autotrophic denitrification according to claim 1, characterized in that: In S2, the amount of lime added is 35-45 mg lime / m 3 Sewage.

9. A sewage treatment device based on sulfate reduction and endogenous sulfur autotrophic denitrification, characterized in that: The method for implementing the method according to any one of claims 1 to 8 comprises an anoxic tank, a settling tank, a sulfur autotrophic denitrification filter and an aerated biological filter connected in sequence, wherein the sludge outlet of the first settling tank is connected to an anaerobic phosphate release tank, the water outlet of the anaerobic phosphate release tank is connected to a second settling tank, and the water outlet of the second settling tank is connected to the sulfur autotrophic denitrification filter.

10. The sewage treatment device based on sulfate reduction and endogenous sulfur autotrophic denitrification according to claim 9, characterized in that: The anaerobic phosphorus release pond is connected to the anoxic pond through a reflux pipe.

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