Sulfur autotrophic filler, preparation method and application thereof, and nitrogen and phosphorus removal device for high-salinity wastewater

Abstract

The invention provides a sulfur autotrophic filler, a preparation method and application thereof, and a nitrogen and phosphorus removal device for high-salinity wastewater. The sulfur autotrophic filler comprises cross-linked gel and sulfur autotrophic denitrifying bacteria, powdered sulfur, siderite powder, trehalose and / or betaine and an auxiliary material which are dispersed in the cross-linked gel; the auxiliary material comprises at least one of volcanic rock powder, medical stone powder and limestone powder. The sulfur autotrophic filler provided by the invention can accelerate rapid enrichment and functional expression of sulfur autotrophic denitrifying bacteria in the application of high-salinity wastewater treatment, deep nitrogen removal and synchronous phosphorus removal of nitrate nitrogen wastewater are realized in a salt stress environment, and the process does not need an organic carbon source, does not need aeration, does not need additional supplementation of a microbial nutritional agent and regulation of pH, and is suitable for industrial production. The advanced treatment and up-to-standard discharge of the high-salinity wastewater can be realized on the premise of saving the occupied area and the operation cost.

Description

Technical Field

[0001] This invention belongs to the field of wastewater treatment technology, specifically relating to a sulfur autotrophic packing material, its preparation method and application, and a device for denitrification and phosphorus removal from high-salt wastewater. Background Technology

[0002] Chemical wastewater is characterized by high salinity, high ammonia nitrogen, and low BOD. After conventional biological treatment for carbon and nitrogen removal, a certain concentration of nitrate nitrogen usually remains in the effluent. With the introduction of stricter national policies on total nitrogen discharge standards for treated water, denitrification units are required after conventional biological treatment for further removal. To ensure deep removal of nitrate nitrogen, excessive amounts of organic carbon sources need to be added to the denitrification unit, which poses a risk of COD exceeding the standard in the effluent. Therefore, an aeration tank is also required, leading to increased treatment process length and larger wastewater treatment unit footprint. Furthermore, traditional denitrification processes also suffer from high levels of residual sludge and greenhouse gas emissions, necessitating further optimization.

[0003] Due to the production characteristics of the chemical industry, the total salt content in chemical wastewater often exceeds 1%. Currently, some chemical wastewater treatment plants use membrane technologies such as ultrafiltration and reverse osmosis for advanced wastewater treatment, achieving high-quality effluent. However, the resulting concentrated water contains even higher concentrations of nitrate nitrogen and salinity. Under salt stress, the denitrification effect of microorganisms is significantly reduced. This is mainly because the higher osmotic pressure in the aquatic environment triggers protoplasmic separation of cells, and salting out reduces the activity of dehydrogenases, thereby inhibiting the metabolic activity of functional microorganisms.

[0004] Sulfotrophic denitrification refers to the process by which sulfurotrophic denitrifying bacteria use reducing sulfur, such as elemental sulfur, as electron donors to reduce nitrate nitrogen to nitrogen gas for removal from water bodies. This process requires no external organic carbon source, produces low-grade sludge, requires no subsequent aeration treatment, and occupies a small area, making it a research and application hotspot in wastewater treatment. However, sulfurotrophic denitrification processes generate some sulfate ions, further increasing wastewater salinity and threatening microbial treatment performance. Therefore, developing a sulfurotrophic process capable of achieving efficient and low-consumption removal of nitrate nitrogen under salt stress is urgently needed.

[0005] CN114291900A discloses a sulfur autotrophic denitrification particle, its preparation method, and its application. The method utilizes biosulfurization, sodium thiosulfate, activated carbon, an encapsulating agent, and sulfur autotrophic denitrifying bacterial solution to prepare a sulfur autotrophic packing material, which is then inoculated into a sulfur autotrophic fluidized bed reactor to achieve NO3- denitrification. - Denitrification of wastewater with a nitrogen concentration of 30 mg / L. However, since the sulfur autotrophic process consumes inorganic carbon sources, an additional amount of inorganic carbon source needs to be added during the wastewater treatment process using the above-mentioned packing material, and the denitrification performance of the packing material is easily inhibited in a salt stress environment.

[0006] CN114524511B discloses an alkaline slow-release porous spherical shell suspension packing material for sulfur autotrophic denitrification based on low C / N wastewater. This material develops a sulfur autotrophic denitrification packing material with a self-supplying inorganic carbon source, capable of maintaining a neutral pH during low C / N wastewater treatment, thus facilitating the smooth progress of the sulfur autotrophic process. However, this packing material is limited to treating low-salinity wastewater, and its effectiveness is not easily realized in the treatment of high-salinity wastewater. Summary of the Invention

[0007] Based on the above analysis, the present invention aims to provide a sulfur self-growth packing material, its preparation method and application, and a device for denitrification and phosphorus removal of high-salt wastewater, in order to solve the technical problems of high nitrate nitrogen content in effluent and poor treatment effect under salt stress in the existing wastewater treatment process.

[0008] The objective of this invention is mainly achieved through the following technical solutions.

[0009] In a first aspect, the present invention provides a sulfur autotrophic filler comprising a cross-linked gel and sulfur autotrophic denitrifying bacteria, sulfur powder, siderite powder, trehalose and / or betaine, and auxiliary materials dispersed in the cross-linked gel; wherein the auxiliary materials comprise at least one of volcanic rock powder, maifanite powder, and limestone powder.

[0010] In the sulfur autotrophic filler provided by the present invention, the components such as sulfur autotrophic denitrifying bacteria, sulfur powder, siderite powder, trehalose and / or betaine, and auxiliary materials are uniformly dispersed on the surface and inside of the crosslinked gel.

[0011] In the sulfur autotrophic packing provided by this invention, the sulfur autotrophic denitrifying bacteria agent can solve the problem of long doubling cycle of autotrophic denitrifying bacteria, and can remove nitrate nitrogen from high-salt wastewater without the need for additional addition of activated sludge or with only a small amount of activated sludge.

[0012] Sulfur powder can be used as an electron donor to remove nitrate nitrogen from wastewater through an autotrophic denitrification process; and the sulfur powder in the packing can be slowly released into the wastewater over a long period of time, so that the system can maintain its long-term treatment effect with a single feeding.

[0013] Pyrite powder carries carbonate ions with a slow-release effect, which can neutralize the H+ produced during the sulfur autotrophic process. + It maintains the normal metabolism of functional microorganisms under neutral pH in the system and provides the necessary inorganic carbon source for the sulfur autotrophic process. In addition, the ferrous ions released by siderite powder and their precipitates can achieve phosphorus removal from wastewater, and the ferrous ions can also serve as electron donors to enhance the denitrification effect.

[0014] Trehalose and / or betaine can be absorbed by functional microorganisms as a low-cost, typical compatible substance, thereby regulating cell osmotic pressure under high-salt wastewater conditions and helping functional microorganisms maintain efficient denitrification under salt stress.

[0015] Volcanic rock powder, maifanite powder and other additives can provide trace elements such as magnesium, calcium and iron necessary for the growth and metabolism of microorganisms, which helps the denitrification and phosphorus removal process to proceed normally. In addition, trace elements can also reduce the redox potential in the system and help siderite maintain a stable pH environment in the system, thus ensuring the effect of wastewater biochemical treatment.

[0016] The sulfur autotrophic packing material provided by this invention features rapid accumulation of sulfur autotrophic denitrifying bacteria and good salt tolerance. It can be used in the autotrophic denitrification process of high-salt wastewater, exhibiting excellent nitrogen and phosphorus removal effects. It can achieve deep denitrification of saline and nitrate-containing tailwater after biological treatment or concentrated water after membrane technology treatment. Compared with the traditional heterotrophic denitrification process, sulfur autotrophic denitrification does not require an external carbon source or subsequent aeration carbon removal process, and produces less residual sludge, which can significantly reduce operating costs.

[0017] According to some embodiments of the present invention, the additive material includes volcanic rock powder.

[0018] In this invention, volcanic rock powder, compared with maifanite powder and limestone powder, has higher porosity and strength, better acid and alkali resistance and corrosion resistance, and is pollution-free and non-radioactive. It can efficiently and safely provide the trace elements necessary for the growth and metabolism of functional bacteria.

[0019] According to some embodiments of the present invention, the mass ratio of the sum of the mass of the sulfur autotrophic denitrifying bacteria agent, sulfur powder, siderite powder, trehalose and / or betaine, and auxiliary materials to the mass ratio of the crosslinked gel based on the gel component is (1-50):1, preferably (5-25):1; the mass ratio of the sulfur autotrophic denitrifying bacteria agent, sulfur powder, siderite powder, trehalose and / or betaine, and auxiliary materials is (10-30):(10-30):(10-30):(5-10):1; the sulfur autotrophic denitrifying bacteria content in the sulfur autotrophic denitrifying bacteria agent is 1×10⁻⁶. 6 ~1×10 9 CFU / mL.

[0020] It should be noted that the cross-linked gel in the sulfur autotrophic packing provided by this invention includes a cross-linked network formed after the gel components are cross-linked and a large amount of water "bound" in the cross-linked network. In this invention, the proportion of the cross-linked gel in the sulfur autotrophic packing is measured by the amount of the gel components. In addition, the sulfur autotrophic denitrifying bacteria in the sulfur autotrophic packing provided by this invention are measured by the bacterial content and dosage in the sulfur autotrophic denitrifying bacteria agent.

[0021] According to some embodiments of the present invention, the crosslinked gel comprises at least one of crosslinked polyethylene glycol, polyvinyl alcohol, sodium alginate, and polyacrylic acid.

[0022] According to some embodiments of the present invention, the sulfur autotrophic denitrifying bacteria belong to the non-salt-tolerant bacteria genus and are a denitrifying functional bacterial group directionally cultured under artificial simulated wastewater conditions with an electrical conductivity of 1000-3000 μm / cm.

[0023] In a second aspect, the present invention provides a method for preparing the sulfur autotrophic filler described in the first aspect, comprising: obtaining a gel suspension comprising a gel component and water; adding sulfur autotrophic denitrifying bacteria, sulfur powder, siderite powder, trehalose and / or betaine, and auxiliary materials to the gel suspension; stirring to obtain a gel mixture; adding the gel mixture dropwise to a crosslinking agent; and then washing and drying the obtained solid to obtain the sulfur autotrophic filler.

[0024] The additive material includes at least one of volcanic rock powder, maifanite powder, and limestone powder.

[0025] According to some embodiments of the present invention, the additive material includes volcanic rock powder.

[0026] According to some embodiments of the present invention, the mass ratio of the sum of the mass of the sulfur autotrophic denitrifying bacteria agent, sulfur powder, siderite powder, trehalose and / or betaine, and auxiliary materials to the mass ratio of the gel component is (1-50):1, preferably (5-25):1; the mass ratio of the sulfur autotrophic denitrifying bacteria agent, sulfur powder, siderite powder, trehalose and / or betaine, and auxiliary materials is (10-30):(10-30):(10-30):(5-10):1; the sulfur autotrophic denitrifying bacteria content in the sulfur autotrophic denitrifying bacteria agent is 1×10⁻⁶. 6 ~1×10 9 CFU / mL.

[0027] According to some embodiments of the present invention, the gel component includes at least one of polyethylene glycol, polyvinyl alcohol, sodium alginate, and polyacrylic acid.

[0028] According to some embodiments of the present invention, the crosslinking agent includes a first crosslinking agent and a second crosslinking agent, wherein the first crosslinking agent includes at least one of calcium chloride, magnesium chloride, and zinc chloride, and the second crosslinking agent includes boric acid and / or sodium tetraborate.

[0029] According to some embodiments of the present invention, the mass ratio of the first crosslinking agent to the second crosslinking agent is (0.5-5):(0.5-5).

[0030] According to some embodiments of the present invention, the mass concentration of the gel component in the gel suspension is 0.5% to 10%, for example, it can be 0.5%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, etc.

[0031] According to some embodiments of the present invention, the gel suspension is prepared under conditions of heating and stirring.

[0032] According to some embodiments of the present invention, the heating temperature is 50-100℃, for example, 50℃, 55℃, 60℃, 70℃, 80℃, 90℃, 95℃, 100℃; the stirring speed is 200-500 rpm, for example, 200 rpm, 300 rpm, 400 rpm, 500 rpm, etc.; the stirring time is 10-60 min, for example, 10 min, 20 min, 30 min, 40 min, 50 min, 60 min, etc.

[0033] According to some embodiments of the present invention, the particle size of the sulfur powder is 50 to 200 mesh.

[0034] According to some embodiments of the present invention, the particle size of the siderite powder is 50 to 200 mesh.

[0035] According to some embodiments of the present invention, the particle size of the additive material is 50 to 200 mesh.

[0036] In this invention, if the particle size of sulfur powder, siderite powder, and auxiliary materials is too large, they will not easily come into contact with the biochemical reaction matrix (such as nitrate nitrogen) to react, and will not be easily utilized by functional bacteria; if the particle size is too small, it will increase the operational difficulty of the preparation process and will not be easy to disperse evenly. Therefore, the particle size of sulfur powder, siderite powder, and auxiliary materials is generally more suitable in the range of 50 to 200 mesh.

[0037] According to some embodiments of the present invention, the gel mixture is added to the crosslinking agent at a constant rate via a peristaltic pump through a pump tube with an inner diameter of 3 to 6 mm, and the peristaltic pump speed is 10 to 50 rpm.

[0038] Thirdly, the present invention provides the application of the sulfur self-growth packing material described in the first aspect or the sulfur self-growth packing material prepared by the preparation method described in the second aspect in wastewater treatment, especially for denitrification and phosphorus removal of high-salt wastewater.

[0039] Fourthly, the present invention provides a device for denitrification and phosphorus removal of high-salinity wastewater, comprising a water distribution layer, a support layer, a packing layer, a transition layer and a clear water separation layer distributed from bottom to top.

[0040] The water distribution layer is used to introduce wastewater pumped in from the lower end of the device into the support layer;

[0041] The support layer is filled with solid particles (e.g., pebbles) with a particle size of 10-50 mm to prevent the device from clogging and to facilitate uniform water distribution.

[0042] The packing layer is filled with the sulfur autotrophic packing material described in the first aspect or the sulfur autotrophic packing material prepared by the preparation method described in the second aspect, for the purpose of denitrification and phosphorus removal treatment of wastewater.

[0043] The transition layer is used to settle suspended solids in wastewater, such as bacterial flocs and / or packing materials that may be suspended, to prevent the loss of large amounts of functional bacteria and / or packing materials.

[0044] The clear water separation layer is used to separate the solid, liquid and gas phases of the treated wastewater, and the separated clear water is discharged through the overflow weir.

[0045] According to some embodiments of the present invention, the packing layer is further filled with activated sludge. The activated sludge may be waste sludge from a wastewater treatment plant.

[0046] According to some embodiments of the present invention, the height-to-diameter ratio of the device is 2-5, wherein the water distribution layer occupies 1 / 15 to 1 / 10 of the effective height of the device, the support layer occupies 1 / 10 to 1 / 8 of the effective height of the device, and the packing layer occupies 1 / 2 to 2 / 3 of the effective height of the device.

[0047] Compared with the prior art, the present invention can achieve at least the following beneficial effects:

[0048] The sulfur autotrophic packing provided by this invention can accelerate the rapid enrichment and functional expression of sulfur autotrophic denitrifying bacteria in the treatment of high-salt wastewater, and achieve deep denitrification and simultaneous phosphorus removal of nitrate nitrogen wastewater in a salt-stressed environment. This process does not require organic carbon sources, aeration, additional microbial nutrients, or pH adjustment, and can achieve deep treatment and compliant discharge of high-salt wastewater while saving land area and operating costs. Attached Figure Description

[0049] Figure 1 The upflow reactor used in the embodiments and comparative examples of this invention.

[0050] Among them, (1) is an upflow reactor, (1.1) is the inlet, (1.2) is the outlet, (1.3) is a peristaltic pump, (1.4) is a water distribution layer, (1.5) is a support layer, (1.6) is a packing layer, (1.7) is a transition layer, and (1.8) is a clear water separation layer. Detailed Implementation

[0051] To make the technical problem to be solved, the technical solution, and the beneficial effects of this invention clearer, the invention will be further described in detail below with reference to specific embodiments. It should be understood that the specific embodiments described herein are merely for illustrating this patent and do not limit the scope of protection of this invention in any way.

[0052] Unless otherwise defined, the technical terms used in the following embodiments have the same meaning as commonly understood by those skilled in the art. Unless otherwise specified, the reagents used in the following embodiments are conventional biochemical reagents; the raw materials, instruments, and equipment used in the following embodiments can all be obtained commercially or by existing methods; unless otherwise specified, the reagent dosages are those used in routine experimental operations; unless otherwise specified, the experimental methods are conventional methods.

[0053] The materials used in the various embodiments and comparative examples of the present invention are as follows:

[0054] Sulfur-autotrophic denitrifying bacterial solution: derived from a long-running sulfur-autotrophic denitrification wastewater treatment device in the laboratory, with a bacterial content of 6 × 10⁻⁶. 6 CFU / mL.

[0055] The particle size of sulfur powder, siderite powder, and maifanite powder is 120 mesh.

[0056] Example 1

[0057] (1) Preparation of sulfur autotrophic filler

[0058] Sodium alginate and deionized water were mixed at a mass ratio of 1:19 and stirred at 300 rpm for 30 minutes at 95°C to prepare a hydrogel suspension. 80 parts by mass of the hydrogel suspension, 20 parts by mass of sulfur-autotrophic denitrifying bacteria solution, 20 parts by mass of sulfur powder, 20 parts by mass of siderite powder, 9 parts by mass of trehalose, and 1 part by mass of maifanite powder were weighed and stirred until homogeneous to obtain a gel mixture. A 3% boric acid solution was prepared. Then, calcium chloride and the boric acid solution were mixed at a mass ratio of 1:49 to prepare a crosslinking agent. The gel mixture was uniformly dripped into the crosslinking agent through a 3mm pump tube at a pump speed of 20 rpm to obtain immobilized particles. The particles were washed three times with deionized water and then dried under natural conditions to obtain the sulfur-autotrophic filler.

[0059] (2) High-salinity wastewater denitrification and phosphorus removal treatment

[0060] Adopting such Figure 1 The upflow reactor 1, with an effective volume of 4.1 L and a height-to-diameter ratio of 3, is shown. The prepared sulfur autotrophic packing material is filled into a packing layer 1.6 with an effective height of 24 cm. Wastewater enters through the lower inlet 1.1 of the device. The HRT (Heat Retention Time) of the packing layer 1.6 is 4 hours. The treated wastewater is discharged through the top outlet 1.2 of the device. Water quality is tested and analyzed daily by taking samples of both influent and effluent.

[0061] NO3 in wastewater to be treated - -N concentration was 60 mg / L, PO4 3--P concentration was 3 mg / L, and TDS concentration was 30,000 mg / L. To ensure successful start-up and superior performance of the wastewater treatment system, a salinity gradient adaptation start-up strategy was adopted. Artificially prepared NO3 was used during days 1-7. - -N concentration was 60 mg / L, PO4 3- Simulated wastewater with a phosphorus concentration of 3 mg / L and a total dissolved solids (TDS) concentration of 10,000 mg / L was used as the influent to the device. The denitrification effect was observed on the second day after startup, with a total nitrogen removal rate of 18.9%. This rate increased to 69.8% on the seventh day. From days 8 to 20, artificially prepared NO3- was used. - -N concentration was 60 mg / L, PO4 3- Simulated wastewater with a phosphorus concentration of 3 mg / L and a total dissolved solids (TDS) concentration of 20,000 mg / L was used as the influent to the device. It was observed that on day 20, the total nitrogen removal rate reached 74.8%, and the total phosphorus removal rate reached 69.9%. Subsequently, the influent was replaced with NO3... - -N concentration was 60 mg / L, PO4 3- For the target wastewater with a phosphorus-to-nitrogen (P) concentration of 3 mg / L and a total dissolved oxygen (TDS) concentration of 30,000 mg / L, the total nitrogen removal rate was maintained at 72.1% and the total phosphorus removal rate was 73.9% on day 32. When the system was running for 50 days, the total nitrogen removal rate increased and stabilized at 95.8% and the total phosphorus removal rate increased and stabilized at 92.9%. A small amount of light brown flocculent sludge detached from the packing material was observed in the packing layer. In summary, the device for nitrogen and phosphorus removal from high-salt wastewater can be considered to have been successfully started up.

[0062] Example 2

[0063] (1) Preparation of sulfur autotrophic filler

[0064] Sodium alginate and deionized water were mixed at a mass ratio of 1:20 and stirred at 300 rpm for 30 minutes at 70°C to prepare a hydrogel suspension. 200 parts by mass of the hydrogel suspension, 30 parts by mass of sulfur-autotrophic denitrifying bacteria solution, 30 parts by mass of sulfur powder, 30 parts by mass of siderite powder, 9 parts by mass of trehalose, and 1 part by mass of maifanite powder were weighed and stirred until homogeneous to obtain a gel mixture. A 3% boric acid solution was prepared. Then, calcium chloride and boric acid solution were mixed at a mass ratio of 1:49 to prepare a crosslinking agent. The gel mixture was uniformly dripped into the crosslinking agent through a 3mm pump tube at a pump speed of 20 rpm to obtain immobilized particles. The particles were washed three times with deionized water and then dried under natural conditions to obtain the sulfur-autotrophic filler.

[0065] (2) The apparatus and method for denitrification and phosphorus removal of high-salt wastewater are described in Example 1.

[0066] The system's nitrogen removal effect was observed on the second day after the device was started, with a total nitrogen removal rate of 17.5%. On the seventh day, the total nitrogen removal rate increased to 68.4%.

[0067] On day 20, the total nitrogen removal rate reached 76.2%, and the total phosphorus removal rate reached 65.9%.

[0068] On day 32, the total nitrogen removal rate remained at 75.1%, and the total phosphorus removal rate was 71.0%.

[0069] When the system ran for 50 days, the total nitrogen removal rate increased and stabilized at 93.2%, and the total phosphorus removal rate increased and stabilized at 94.7%. A small amount of light brown flocculent sludge that had detached from the packing material was observed in the packing layer.

[0070] In summary, the device for nitrogen and phosphorus removal from high-salinity wastewater can be considered to have been successfully started up.

[0071] Example 3

[0072] (1) The preparation method of the sulfur self-growth filler is the same as in Example 1, except that 9 parts of trehalose are replaced with 9 parts of betaine.

[0073] (2) The apparatus and method for denitrification and phosphorus removal of high-salt wastewater are described in Example 1.

[0074] The system's nitrogen removal effect was observed on the second day after the device was started, with a total nitrogen removal rate of 19.3%. On the seventh day, the total nitrogen removal rate increased to 66.3%.

[0075] On day 20, the total nitrogen removal rate reached 72.0%, and the total phosphorus removal rate reached 65.9%.

[0076] On day 32, the total nitrogen removal rate remained at 70.8%, and the total phosphorus removal rate was 72.1%.

[0077] When the system ran for 50 days, the total nitrogen removal rate increased and stabilized at 96.2%, and the total phosphorus removal rate increased and stabilized at 91.8%. A small amount of light brown flocculent sludge that had detached from the packing material was observed in the packing layer.

[0078] In summary, the device for nitrogen and phosphorus removal from high-salinity wastewater can be considered to have been successfully started up.

[0079] Example 4

[0080] (1) The preparation method of sulfur self-growth filler is as described in Example 1.

[0081] (2) The apparatus and method for denitrification and phosphorus removal of high-salt wastewater are the same as in Example 1, except that the prepared sulfur autotrophic packing and a small amount of residual sludge from the sewage treatment plant are filled into a packing layer with an effective height of 24cm, and the MLSS of suspended sludge in the system is 1000mg / L.

[0082] The system's nitrogen removal effect was observed on the second day after the device was started, with a total nitrogen removal rate of 19.8%, which increased to 72.7% on the seventh day.

[0083] On day 20, the total nitrogen removal rate reached 77.6%, and the total phosphorus removal rate reached 70.9%.

[0084] On day 32, the total nitrogen removal rate remained at 76.4%, and the total phosphorus removal rate was 79.2%.

[0085] When the system ran for 50 days, the total nitrogen removal rate increased and stabilized at 95.8%, and the total phosphorus removal rate increased and stabilized at 93.1%. A large amount of light brown flocculent sludge that had detached from the packing material was observed in the packing layer.

[0086] In summary, the device for nitrogen and phosphorus removal from high-salinity wastewater can be considered to have been successfully started up.

[0087] Example 5

[0088] (1) The preparation method of sulfur self-growth filler is the same as in Example 1, except that 1 part of maifanite powder is replaced with 1 part of volcanic rock powder.

[0089] (2) The apparatus and method for denitrification and phosphorus removal of high-salt wastewater are described in Example 1.

[0090] The system's nitrogen removal effect was observed on the second day after the device was started, with a total nitrogen removal rate of 20.1%. On the seventh day, the total nitrogen removal rate increased to 75.6%.

[0091] On day 20, the total nitrogen removal rate reached 82.6%, and the total phosphorus removal rate reached 81.8%.

[0092] On day 32, the total nitrogen removal rate remained at 87.0%, and the total phosphorus removal rate was 86.9%.

[0093] When the system ran for 50 days, the total nitrogen removal rate increased and stabilized at 97.8%, and the total phosphorus removal rate increased and stabilized at 98.3%. A small amount of light brown flocculent sludge that had detached from the packing material was observed in the packing layer.

[0094] In summary, the device for nitrogen and phosphorus removal from high-salinity wastewater can be considered to have been successfully started up.

[0095] Example 6

[0096] (1) The preparation method of the sulfur self-growth filler is the same as in Example 1, except that 1 part of maifan stone powder is replaced with 1 part of limestone powder.

[0097] (2) The apparatus and method for denitrification and phosphorus removal of high-salt wastewater are described in Example 1.

[0098] The system's nitrogen removal effect was observed on the second day after the device was started, with a total nitrogen removal rate of 17.0%. On the seventh day, the total nitrogen removal rate increased to 66.2%.

[0099] On day 20, the total nitrogen removal rate reached 72.5%, and the total phosphorus removal rate reached 69.1%.

[0100] On day 32, the total nitrogen removal rate remained at 71.4%, and the total phosphorus removal rate was 70.2%.

[0101] When the system ran for 50 days, the total nitrogen removal rate increased and stabilized at 91.7%, and the total phosphorus removal rate increased and stabilized at 93.3%. A small amount of light brown flocculent sludge that had detached from the packing material was observed in the packing layer.

[0102] In summary, the device for nitrogen and phosphorus removal from high-salinity wastewater can be considered to have been successfully started up.

[0103] Comparative Example 1

[0104] (1) The preparation method of the packing is the same as in Example 4, except that 20 parts of sulfur autotrophic denitrifying bacteria solution are not added.

[0105] (2) The apparatus and method for denitrification and phosphorus removal of high-salt wastewater are described in Example 3.

[0106] No significant removal of total nitrogen and total phosphorus was observed on the 7th day after the device was started.

[0107] On day 20, the total nitrogen removal rate was 12.6%, and the total phosphorus removal rate was 8.9%.

[0108] On day 50, the total nitrogen removal rate was 46.5%, and the total phosphorus removal rate remained stable at 53.7%. Light brown flocculent sludge detached from the packing material was observed in the packing layer.

[0109] In summary, it can be concluded that due to the lack of functional microorganisms in the new packing material, the start-up speed of the device for denitrification and phosphorus removal in high-salt wastewater is slow, and it needs to be acclimatized for a long time before it can be put into use.

[0110] Comparative Example 2

[0111] (1) The preparation method of the filler is the same as in Example 1, except that 20 parts of sulfur powder are not added.

[0112] (2) The apparatus and method for denitrification and phosphorus removal of high-salt wastewater are described in Example 1.

[0113] No significant removal of total nitrogen and total phosphorus was observed on the 7th day after the device was started.

[0114] No significant removal of total nitrogen and total phosphorus was observed on day 20.

[0115] No significant total nitrogen removal effect was observed on day 50, and the total phosphorus removal rate was only 5.5%.

[0116] In summary, it can be concluded that the failure to start up the device for denitrification and phosphorus removal from high-salt wastewater is due to the lack of sulfur powder, which is necessary for the denitrification process, in the packing material.

[0117] Comparative Example 3

[0118] (1) The preparation method of the filler is the same as in Example 1, except that 20 parts of siderite powder are not added.

[0119] (2) The apparatus and method for denitrification and phosphorus removal of high-salt wastewater are described in Example 1.

[0120] On the 7th day after the unit was started, a total nitrogen removal rate of 17.7% was observed.

[0121] On day 20, the total nitrogen removal rate was 24.3%, and no phosphorus removal effect was observed.

[0122] Due to insufficient inorganic carbon source in the system, the denitrification effect deteriorated, and the total nitrogen removal rate was only 12.1% on the 50th day, with no phosphorus removal effect observed.

[0123] In summary, it can be concluded that the lack of carbonate ions for pH adjustment and inorganic carbon source, as well as iron particles for phosphorus removal, in the new packing material led to the start-up failure of the device for denitrification and phosphorus removal from high-salt wastewater.

[0124] Comparative Example 4

[0125] (1) The preparation method of the filler is the same as in Example 1, except that 9 parts of trehalose are not added.

[0126] (2) The apparatus and method for denitrification and phosphorus removal of high-salt wastewater are described in Example 1.

[0127] On the 7th day after the unit was started, a total nitrogen removal rate of 62.1% could be observed.

[0128] On day 20, the total nitrogen removal rate decreased to 44.9%, and the total phosphorus removal rate was 32.7%.

[0129] On day 50, the total nitrogen removal rate was only 27.8%, and the total phosphorus removal rate was 33.2%.

[0130] In summary, it can be concluded that the lack of components for regulating cell osmotic pressure in the new packing material led to the failure of the device for nitrogen and phosphorus removal from high-salt wastewater to start up.

[0131] Comparative Example 5

[0132] (1) The preparation method of the filler is the same as in Example 1, except that: no 1 part of maifan stone powder is added.

[0133] (2) The apparatus and method for denitrification and phosphorus removal of high-salt wastewater are described in Example 1.

[0134] On the 7th day after the unit was started, a total nitrogen removal rate of 63.9% could be observed.

[0135] On day 20, the total nitrogen removal rate was 60.7%, and the total phosphorus removal rate was 52.3%.

[0136] On day 50, the total nitrogen removal rate was 62.8%, and the total phosphorus removal rate was 55.2%.

[0137] In summary, although the comparative packing material and wastewater treatment device can achieve partial removal of total nitrogen and total phosphorus, the effluent still fails to meet the standards. This is mainly because the packing material lacks the trace elements required for the growth and metabolism of functional microorganisms, which affects the normal denitrification and phosphorus removal processes of microorganisms. Therefore, the packing material has a poor effect on deep denitrification and phosphorus removal when treating high-salt wastewater, and the wastewater treatment device cannot achieve deep treatment and compliant discharge.

[0138] It should be noted that the embodiments described above are only for explaining the present invention and do not constitute any limitation on the present invention. The present invention has been described with reference to typical embodiments, but it should be understood that the words used therein are descriptive and explanatory terms, not limiting terms. Modifications can be made to the present invention within the scope of the claims, and revisions can be made to the present invention without departing from the scope and spirit of the present invention. Although the present invention described herein relates to specific methods, materials, and embodiments, it does not mean that the present invention is limited to the specific examples disclosed herein; on the contrary, the present invention can be extended to all other methods and applications with the same function.

Claims

1. A sulfur-based self-growth filler, characterized in that, It includes a cross-linked gel and sulfur autotrophic denitrifying bacteria, sulfur powder, siderite powder, trehalose and / or betaine, and auxiliary materials dispersed in the cross-linked gel; the auxiliary materials include at least one of volcanic rock powder, maifanite powder, and limestone powder.

2. The sulfur self-growth filler according to claim 1, characterized in that, The mass ratio of the sum of the mass of the sulfur autotrophic denitrifying bacteria agent, sulfur powder, siderite powder, trehalose and / or betaine, and auxiliary materials to the mass of the crosslinked gel based on the gel component is (1-50):1, preferably (5-25):1; The mass ratio of sulfur autotrophic denitrifying bacteria, sulfur powder, siderite powder, trehalose and / or betaine, and auxiliary materials is (10-30):(10-30):(10-30):(5-10):1; The sulfur-autotrophic denitrifying bacteria in the sulfur-autotrophic denitrifying bacteria agent contains 1×10⁻⁶ sulfur-autotrophic denitrifying bacteria. 6 ~1×10 9 CFU / mL.

3. The sulfur self-growth filler according to claim 1 or 2, characterized in that, The cross-linked gel includes at least one of cross-linked polyethylene glycol, polyvinyl alcohol, sodium alginate, and polyacrylic acid.

4. The method for preparing the sulfur self-growth filler according to any one of claims 1-3, characterized in that, include: A gel suspension comprising gel components and water is obtained. Sulfur autotrophic denitrifying bacteria, sulfur powder, siderite powder, trehalose and / or betaine, and auxiliary materials are added to the gel suspension and stirred to obtain a gel mixture. The gel mixture is then added dropwise to a crosslinking agent. The resulting solid is then washed and dried to obtain the sulfur autotrophic filler. The additive material includes at least one of volcanic rock powder, maifanite powder, and limestone powder.

5. The preparation method according to claim 4, characterized in that, The mass ratio of the sum of the mass of the sulfur autotrophic denitrifying bacteria agent, sulfur powder, siderite powder, trehalose and / or betaine, and auxiliary materials to the mass of the gel component is (1-50):1, preferably (5-25):1; The mass ratio of sulfur autotrophic denitrifying bacteria, sulfur powder, siderite powder, trehalose and / or betaine, and auxiliary materials is (10-30):(10-30):(10-30):(5-10):1; The sulfur-autotrophic denitrifying bacteria in the sulfur-autotrophic denitrifying bacteria agent contains 1×10⁻⁶ sulfur-autotrophic denitrifying bacteria. 6 ~1×10 9 CFU / mL.

6. The preparation method according to claim 4 or 5, characterized in that, The gel component includes at least one of polyethylene glycol, polyvinyl alcohol, sodium alginate, and polyacrylic acid; And / or, the crosslinking agent includes a first crosslinking agent and a second crosslinking agent, wherein the first crosslinking agent includes at least one of calcium chloride, magnesium chloride, and zinc chloride, and the second crosslinking agent includes boric acid and / or sodium tetraborate; preferably, the mass ratio of the first crosslinking agent to the second crosslinking agent is (0.5-5):(0.5-5).

7. The preparation method according to any one of claims 4-6, characterized in that, The mass concentration of the gel component in the gel suspension is 0.5% to 10%. And / or, the gel suspension is prepared under heating and stirring conditions; preferably, the heating temperature is 50-100°C; the stirring speed is 200-500 rpm; and the stirring time is 10-60 min.

8. The preparation method according to any one of claims 4-7, characterized in that, The sulfur powder has a particle size of 50-200 mesh; And / or, the particle size of the siderite powder is 50-200 mesh; And / or, the particle size of the auxiliary material is 50 to 200 mesh.

9. The application of the sulfur self-growth packing material according to any one of claims 1-3 or the sulfur self-growth packing material prepared by the preparation method according to any one of claims 4-8 in wastewater treatment, especially for denitrification and phosphorus removal of high-salinity wastewater.

10. A device for denitrification and phosphorus removal from high-salinity wastewater, characterized in that, It includes, from bottom to top, a water distribution layer, a support layer, a filler layer, a transition layer, and a clear water separation layer; The water distribution layer is used to introduce wastewater pumped in from the lower end of the device into the support layer; The support layer is filled with solid particles with a particle size of 10-50mm to prevent the device from clogging and to facilitate uniform water distribution. The packing layer is filled with the sulfur autotrophic packing material according to any one of claims 1-3 or the sulfur autotrophic packing material prepared by the preparation method according to any one of claims 4-8, for the purpose of denitrification and phosphorus removal treatment of wastewater; The transition layer is used to settle suspended solids in wastewater; The water separation layer is used for solid-liquid-gas three-phase separation of the treated wastewater; Preferred, The height-to-diameter ratio of the device is 2-5, wherein the water distribution layer occupies 1 / 15 to 1 / 10 of the effective height of the device, the support layer occupies 1 / 10 to 1 / 8 of the effective height of the device, and the filler layer occupies 1 / 2 to 2 / 3 of the effective height of the device.

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