CN118062991B - Light and reusable sulfur autotrophic denitrification filler and preparation method thereof - Google Patents

Abstract

The invention discloses a lightweight, reusable sulfur autotrophic denitrification filler and a preparation method thereof. A sulfur autotrophic denitrification filler, the preparation raw materials of which include: sulfur powder, white iron ore powder, aluminum hydroxide powder, wood cellulose, anionic polyacrylamide, sepiolite and porous resin. The autotrophic denitrification filler of the invention is characterized by being lightweight, easy to replace and having high mass transfer efficiency by combining multiple raw materials.

Description

A lightweight, reusable sulfur autotrophic denitrification filler and preparation method thereof

Technical Field

The invention relates to the field of preparation of environmental functional materials, and in particular to a lightweight, reusable sulfur autotrophic denitrification filler and a preparation method thereof.

Background Art

In the traditional process of denitrification of wastewater with low C/N ratio, since heterotrophic denitrifying bacteria are used for denitrification reduction, microorganisms need sufficient organic carbon sources. For wastewater with low C/N ratio, a large amount of external organic carbon sources, such as methanol, sodium acetate and glucose, are often used. The large amount of external organic carbon sources will lead to an increase in sewage treatment costs, a large amount of residual sludge, and the sludge is easy to swell and difficult to settle, and the overall management cost increases.

For wastewater with low C/N ratio, the main way to reduce costs is to reduce or completely avoid the use of external carbon sources. For this, research is mainly focused on autotrophic biological denitrification processes. For example, anaerobic ammonia oxidation, hydrogen autotrophic denitrification and sulfur autotrophic denitrification, although anaerobic ammonia oxidation and hydrogen autotrophic denitrification do not require external carbon sources, the growth environment conditions required by their microorganisms are relatively harsh, and general engineering conditions are difficult to meet the needs of their stable use. The removal rate of low-concentration total nitrogen is poor, and it is difficult to achieve deep denitrification. Therefore, sulfur autotrophic denitrification is more suitable for industrial water treatment.

Sulfur autotrophic denitrification mainly relies on sulfur or other reduced sulfur compounds as electron donors, and uses nitrite nitrogen and nitrate nitrogen as electron acceptors, ultimately achieving the conversion of nitrogen into nitrogen gas and removing it from the sewage system. Sulfur autotrophic denitrification requires a certain amount of reduced sulfur as an electron donor. In addition, sulfur autotrophic denitrification consumes alkalinity, and the reaction also requires the addition of alkalinity. The residual sludge output is small. When suitable reduced sulfur is selected as the sulfur source, the operation and management costs can be greatly reduced.

At present, sulfur autotrophic denitrification uses more solid fillers. Microorganisms are inoculated on substances loaded with reducing sulfur to form a biofilm on the surface of the filler to achieve a rapid denitrification reaction. However, there are many problems with the use of this type of solid filler. For example, most of the fillers are currently submerged fillers, which have a large density and are more troublesome to load and unload. When the reactor is running, an additional support frame needs to be installed, and the metal frame is prone to corrosion, which poses a potential risk. In addition, the reusability of sludge when supplementing fillers is not considered, such as coated fillers and some solid phase fillers. Most of the successfully domesticated sludge adheres to the original filler and is not easy to transfer. The addition of new fillers will cause the sludge to be re-domesticated or the sludge to be washed and biofilmed, which increases the cost of use and technical complexity. For embedded fillers, their preparation and processing procedures are complicated. The sulfur source embedded in the final filler is often difficult to transfer with microorganisms due to its own solubility in water. The widely used polyvinyl alcohol and sodium alginate have certain biodegradability, which also allows heterotrophic microorganisms to attach to them, thereby occupying the ecological niche of sulfur autotrophic microorganisms, making it difficult to start and domesticate sulfur autotrophic denitrification.

Therefore, in view of the shortcomings of the above-mentioned sulfur autotrophic denitrification filler, it is necessary to prepare and develop a sulfur autotrophic denitrification filler that is lightweight, easy to replace and has high mass transfer efficiency.

Summary of the invention

In view of the shortcomings of current sulfur autotrophic denitrification fillers, the present invention provides a lightweight and reusable sulfur autotrophic denitrification filler and a preparation method thereof.

In order to achieve the above object, the technical solution adopted by the present invention is:

The first aspect of the present invention provides a sulfur autotrophic denitrification filler, and the raw materials for preparing the filler include: sulfur powder, white iron ore powder, aluminum hydroxide powder, wood cellulose, anionic polyacrylamide, sepiolite and porous resin.

Preferably, the mass ratio of the sulfur powder, white iron ore powder, aluminum hydroxide powder and cellulose is (2.5-3.5):(0.5-1.5):(0.1-0.2):(0.01-0.05); further preferably, the mass ratio of the sulfur powder, white iron ore powder, aluminum hydroxide powder and cellulose is 3:(0.5-1.5):(0.1-0.2):(0.01-0.05).

Preferably, the mass ratio of the anionic polyacrylamide to the sepiolite is (1-3):(2-4).

Preferably, the mass ratio of the sulfur powder to anionic polyacrylamide is 3:(0.02-0.06); further preferably, the mass ratio of the sulfur powder to anionic polyacrylamide is 3:(0.04-0.06).

Preferably, the particle size of the sulfur powder is ≥300 mesh, the particle size of the white iron ore powder is ≥200 mesh, the particle size of the aluminum hydroxide powder is ≥200 mesh, and the length of the wood cellulose is 1 to 3 mm.

Preferably, the particle size of the sepiolite is 2 to 4 mm.

Preferably, the porous resin comprises PVC porous resin, and the PVC porous resin material has a porous foam appearance, and the size and pore size of the monomer material vary according to the reactor volume.

Preferably, the anionic polyacrylamide has a molecular weight of 8 to 14 million and is soluble in water and exhibits weak alkalinity.

The second aspect of the present invention provides a method for preparing the sulfur autotrophic denitrification filler, comprising the following steps:

(1) mixing sulfur powder, white iron ore powder, aluminum hydroxide powder, and lignocellulose to obtain a mixed dry material;

(2) mixing anionic polyacrylamide, sepiolite particles and water to obtain an adhesive protective agent;

(3) adding the adhesive protective agent to the mixed dry material, mixing and kneading, and stirring to obtain a mixed wet material;

(4) adding the mixed wet material into a porous resin, extruding and kneading, taking it out and draining it, and drying it to obtain the sulfur autotrophic denitrification filler.

In the present invention, when the sulfur source in the sulfur autotrophic denitrification filler is consumed to a certain extent, the filler with sludge can be taken out, and the mixed wet material in step (3) is directly taken to re-extrude and knead it, and then dried at low temperature until there is no obvious water droplets, and then put back into the sulfur autotrophic denitrification reactor.

In the preparation method of the present invention, the water in step (2) can be water at room temperature or below 38° C. In order to ensure that the mixing and dissolution are complete, the stirring time needs to be adjusted accordingly.

Preferably, in step (2), the mass ratio of the anionic polyacrylamide, sepiolite particles and water is (1-3):(2-4):(95-100).

Preferably, in step (3), the usage ratio of the adhesive protective agent to the mixed dry material is (50-100) mL: (100-150) g.

Preferably, in step (4), the amount of the mixed wet material is 1 ^dm3 of porous resin plus (800-1200) mL of the mixed wet material.

Preferably, in step (4), the drying temperature is ≤42° C., and the degree of drying is such that there are no obvious water droplets on the surface of the filler.

Compared with the prior art, the present invention has the following beneficial effects:

(1) The present invention provides a lightweight, reusable sulfur autotrophic denitrification filler, which uses aluminum hydroxide as the main alkalinity supplementer. Compared with strong alkalis such as slaked lime, the alkalinity supplement used in the present invention has a slow-release function, which can achieve long-term stable alkalinity supplementation and control pH stability; compared with minerals such as calcium carbonate as alkalinity supplements, it is more efficient and will not cause problems such as excessive calcium ion concentration in the reactor leading to sludge calcification and pipe scaling.

(2) The present invention provides a lightweight, reusable sulfur autotrophic denitrification filler, using lignocellulose as a filler material. Compared with other mineral fillers, the filler material used in the present invention has the advantages of being lightweight, having good filling performance, improving filler roughness, and increasing a large number of microbial attachment points. In addition, lignocellulose can be used as a powder dispersant to avoid the agglomeration of each powder, resulting in uneven filler composition.

(3) The present invention provides a lightweight, reusable sulfur autotrophic denitrification filler, which uses a large amount of lightweight materials, reserves internal bubbles through kneading and extrusion, and produces a large number of hollow micropores (through holes) after drying. Compared with other submerged fillers, the sulfur autotrophic denitrification filler prepared by the present invention has a smaller volume density than water. After sulfur autotrophic denitrification produces nitrogen, it can be suspended in water, which is convenient for transportation and storage, and easy for loading and unloading.

(4) The present invention provides a lightweight, reusable sulfur autotrophic denitrification filler, which uses a PVC resin porous material as the main skeleton material of the filler. Compared with other solid phase fillers, the sulfur autotrophic denitrification filler prepared by the PVC resin porous material of the present invention has strong plasticity and good elasticity. At the same time, it has higher structural strength than the traditional polyurethane sponge. It can be used in various reactors and achieve low water resistance, avoiding the "short flow" phenomenon, and it is not easy to produce local extrusion between the fillers, resulting in serious deformation and uneven mass transfer.

(5) The present invention provides a lightweight, reusable sulfur autotrophic denitrification filler, which uses anionic PAM and sepiolite particles to add water to prepare an adhesive protective agent. Compared with other adhesives, anionic PAM can not only fully provide viscosity and water retention capacity, but also does not need to be dissolved at high temperature, which provides a feasible prerequisite for reusing fillers. Its adhesive protective agent can be dissolved or utilized over time by controlling the molecular weight, thereby achieving a slow release effect on the sulfur source and alkalinity supplement. The high water absorption of sepiolite particles can further fill the gaps in the filler, and has a high water permeability, preventing the loss of microorganisms and sulfur sources, and providing more microbial biofilm sites. In addition, anionic PAM and sepiolite particles are selected because these two types of materials can slowly release a certain amount of alkaline substances in pure water, which can serve as auxiliary alkalinity supplements to improve the stability of the reactor.

(6) The present invention provides a lightweight, reusable sulfur autotrophic denitrification filler, in which the sulfur source used contains marcasite. After optimization, among the types of pyrites traditionally used, the redox rate of pyrite is lower than that of marcasite, and marcasite is more easily utilized by sulfur autotrophic microorganisms. Therefore, the use of marcasite can solve the problem of low utilization rate of pyrite and further enhance the ability of iron-mediated enhanced sulfur autotrophic denitrification.

(7) The present invention provides a lightweight, reusable sulfur autotrophic denitrification filler, which has a special structure to achieve reuse. The sulfur autotrophic denitrification filler only needs to be taken out, drained, and the filler with sludge is directly kneaded with the mixed wet material, dried until there is no obvious water droplets on the surface, and then put back into the reactor.

(8) The present invention provides a lightweight, reusable sulfur autotrophic denitrification filler, which has more abundant microbial attachment sites than other fillers, and while achieving uniform mass transfer, the sludge is not easy to lose, and can complete biofilm in a short period of time, accelerating the sludge domestication. Compared with other technologies, it does not require complex processing processes such as high-temperature heating, granulation, and uniform control of coating, saving production costs and improving the filler yield, which is beneficial to enterprise production and processing.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a physical diagram of the sulfur autotrophic denitrification filler of the present invention;

FIG2 is a diagram showing the denitrification effect of the reactor of Example 4;

FIG3 is a diagram showing the denitrification effect of the reactor of Example 5;

FIG4 is a diagram showing the denitrification effect of the reactor of Example 6;

FIG5 is a diagram showing the relative abundance of microbial communities at the sludge level of the embodiment;

FIG. 6 shows the relative abundance of microbial communities at the genus level in the sludge of the embodiment.

DETAILED DESCRIPTION

The specific embodiments of the present invention are further described below. It should be noted that the description of these embodiments is used to help understand the present invention, but does not constitute a limitation of the present invention. In addition, the technical features involved in each embodiment of the present invention described below can be combined with each other as long as they do not conflict with each other.

The experimental methods in the following examples are conventional methods unless otherwise specified, and the experimental materials used in the following examples are commercially available unless otherwise specified.

Example 1

(1) Take 1 g of aluminum hydroxide powder, 4 g of APAM and 6 g of sepiolite particles and add them into three beakers filled with 200 mL of pure water respectively. Seal the beakers with sealing film to prevent air from affecting the experiment. Stir the three beakers with magnetic stirring at 120 r/min for 1 hour.

(2) After the stirring was completed, the mixture was allowed to stand for 1 hour and the pH value of the supernatant was measured. The results are shown in Table 1:

Table 1

Experimental drugs pH Aluminum hydroxide solution 8.17 APAM Solution 8.19 Sepiolite solution 8.34

According to the above experimental results, it can be found that the constituent materials used in the biological filler prepared by the present invention are mainly weakly alkaline, and due to their microsolubility and weak hydrolysis, the alkalinity provided is slowly released. The hydroxide ion concentration will affect the release of alkalinity. When the pH is higher, the alkalinity is released more slowly, acting as a buffer substance. Different from the prior art, the filler using three alkalinity supplements has a stronger alkalinity regulation ability and no calcium ion release, which continuously provides sulfur autotrophic microorganisms with a stable environment to adapt.

Example 2

(1) 300 g of sulfur powder, 100 g of white iron ore powder, 10 g of aluminum hydroxide powder and 5 g of lignocellulose were fully mixed to obtain a mixed dry material 1;

(2) Take 2g APAM and 6g sepiolite particles and slowly add them into a beaker containing 180mL pure water. Under the same other conditions, replace 2g APAM with 4g APAM and 6g APAM and add them to the other two beakers. At this time, three different formulations of adhesive protective agents are obtained.

(3) Add three different adhesive protective agents to the mixed dry materials at a ratio of 75 mL of adhesive protective agent to 100 g of mixed dry materials, and stir thoroughly until the wood cellulose can be found to expand significantly, thereby obtaining three different mixed wet materials.

(4) Take three portions of 150 cubic centimeters of PVC resin porous material, the average size of each single material is 2cm*2cm*2cm. Take 150mL of the mixed wet materials of three different formulas and add them to 150 cubic centimeters of PVC resin porous material respectively, mix them thoroughly, squeeze and knead them to promote foaming for 15 minutes. After kneading is completed, dry them at low temperature until there are no obvious water droplets on the surface, and a lightweight, reusable sulfur autotrophic denitrification filler is obtained.

(5) Three different formulations of sulfur autotrophic denitrification fillers were loaded into three 1L upflow reactors. The inlet water was a distribution water with a pH value of 7.5-8.0, a nitrate nitrogen concentration of 200mg/L, an ammonia nitrogen concentration of 5mg/L, a total phosphorus of 1mg/L, a hydraulic retention time of 12h, a distribution water alkalinity of 600mg/L (calculated as _CaCO3 ), and no organic matter was added. The sludge was taken from an anaerobic reactor that had been in stable operation for one year in the enterprise, and the concentration of the prepared sludge mixed liquor was about 3000mg/L MLVSS. The nitrate nitrogen and total phosphorus of the three reactors were measured regularly. The results are shown in Table 2-3 below:

Table 2

Table 3

According to the above data, it can be found that the prepared sulfur autotrophic denitrification filler has a certain denitrification and phosphorus removal capacity when used in the sulfur autotrophic reactor, and it can be determined that the optimal addition amount of APAM is 4g. During the 30-day reactor startup operation, no additional organic carbon source was added, and the nitrate nitrogen removal rate reached a maximum of 71.76%, and the total nitrogen removal rate reached a maximum of 90%, proving that the prepared sulfur autotrophic denitrification filler can achieve in-situ acclimation startup and achieve relatively good denitrification and phosphorus removal effects.

Example 3

(1) 300 g of sulfur powder, 100 g of white iron ore powder, 10 g of aluminum hydroxide powder and 5 g of lignocellulose are mixed thoroughly to obtain a mixed dry material 1; another 300 g of sulfur powder, 100 g of white iron ore powder and 5 g of lignocellulose are mixed thoroughly to obtain a mixed dry material 2, which differs from the mixed dry material 1 in the presence or absence of aluminum hydroxide powder.

(2) 4 g of APAM and 6 g of sepiolite particles were slowly added to a beaker containing 180 mL of pure water, and the mixture was stirred thoroughly to obtain an adhesive protective agent 1. Meanwhile, another 4 g of APAM was slowly added to a beaker containing 180 mL of pure water, and the mixture was stirred thoroughly to obtain an adhesive protective agent 2, which differed from the adhesive protective agent 1 in the presence or absence of the addition of sepiolite particles.

(3) Mix the mixed dry materials in a ratio of 75 mL of adhesive protective agent: 100 g, and combine them into mixed wet materials with different formulas. The formulas are mixed wet material 1, which is mixed dry material 1 + adhesive protective agent 1, mixed wet material 2, which is mixed dry material 1 + adhesive protective agent 2, mixed wet material 3, which is mixed dry material 2 + adhesive protective agent 1, and mixed wet material 4, which is mixed dry material 2 + adhesive protective agent 2.

(4) Take 4 portions of 150 cubic centimeters of PVC resin porous material, the average size of each single material is 2cm*2cm*2cm. Take 150 mL of each of the four different formulas of mixed wet materials and add them to 150 cubic centimeters of PVC resin porous material, mix them thoroughly, squeeze and knead them to promote foaming for 15 minutes. After kneading is completed, dry them at low temperature until there are no obvious water droplets on the surface, and sulfur autotrophic denitrification filler 1, control group 2, control group 3, and control group 4 are obtained.

(5) Four different formulations of fillers were loaded into four 1L upflow reactors. The inlet water was a distribution water with a pH value of 7.5-8.0, a nitrate nitrogen concentration of 200mg/L, an ammonia nitrogen concentration of 5mg/L, a total phosphorus of 2mg/L, a hydraulic retention time of 12h, a distribution water alkalinity of 600mg/L (calculated as _CaCO3 ), and no organic matter was added. The sludge was taken from an anaerobic reactor that had been in stable operation for one year, and the concentration of the prepared sludge mixed liquor was about 3000mg/L MLVSS. At the same time, an internal recirculation was designed, and the daily recirculation water volume was 6L/d. The nitrate nitrogen and total phosphorus of the four reactors were measured regularly. The results are shown in Table 4-5:

Table 4

Table 5

According to the data in Table 4-5, it can be found that different material compositions have different denitrification and dephosphorization capabilities. In particular, the filler made by adding other materials such as aluminum hydroxide and sepiolite particles at the same time has significantly better denitrification and dephosphorization capabilities than the filler made without aluminum hydroxide or sepiolite particles.

Example 4

(1) 10L of filler was prepared with the formula of sulfur autotrophic denitrification filler 1 in Example 3, and loaded into a sulfur autotrophic reactor 1 (hereinafter referred to as "reactor 1") with a height of 55 cm and a radius of 10 cm, with a filling height of 30 cm and a designed safety water level of 5 cm. Another sulfur autotrophic reactor 2 (hereinafter referred to as "reactor 2") with the same specifications as sulfur autotrophic reactor 1 was prepared, which was loaded with pure sulfur blocks, with a filling height of 30 cm and a designed safety water level of 5 cm. Since the reactor loaded with submerged fillers such as pure sulfur blocks brings greater water resistance than the reactor loaded with sulfur autotrophic filler 1, the reactor operation only controls the reflux flow rate to be consistent with the rising flow rate.

(2) 4 L of precipitated sludge from the anaerobic reaction tank of a municipal sewage plant was added to the reactor 1 and the reactor 2 at the same time, and the sludge concentration was MLVSS = 12 g/L.

(3) The circuit board complex wastewater that has been subjected to physical and chemical treatment and biochemical treatment is taken as the inlet water of reactor 1 and reactor 2. The inlet water has a pH value of 7.5-8.0, a nitrate nitrogen concentration of 120-140 mg/L, an ammonia nitrogen concentration of about 2.5 mg/L, and a total phosphorus concentration of 1 mg/L by adding potassium dihydrogen phosphate. The hydraulic retention time is 12 hours, the alkalinity is 600 mg/L (calculated as CaCO ₃ ), and no additional organic matter is added. The sludge is taken from the anaerobic reactor that has been stably operated for one year in the enterprise, and the concentration of the prepared sludge mixed liquor is about 3000 mg/LMLVSS. At the same time, an internal recirculation is designed, and the daily recirculation water volume is 6L/d. The nitrate nitrogen of the three reactors is measured every two days. After 80 days of operation, the results are shown in Figure 2.

According to Figure 2, it can be found that the sulfur autotrophic denitrification filler 1 has obvious advantages over the traditional sulfur block in terms of sulfur autotrophic denitrification capacity. It not only has a higher denitrification efficiency, but also has a shorter start-up time, and can achieve deep denitrification, reducing the nitrate nitrogen in the effluent to below 1 mg/L. The wastewater treated in this comparative experiment is the circuit board complex wastewater that has been treated with physical and chemical treatment and biological nitrification. This comparative experiment shows that the sulfur autotrophic denitrification filler 1 has excellent denitrification capacity for this type of wastewater.

Example 5

The reactor in Example 4 was used to continue the test, only the test water was changed, and the rest remained unchanged. The influent was changed to circuit board comprehensive wastewater, with a pH of 8.0-9.5, a nitrate nitrogen concentration of 30-60 mg/L, an ammonia nitrogen concentration of 1.5 mg/L, and a total phosphorus concentration of 1 mg/L by adding potassium dihydrogen phosphate.

The nitric nitrogen in the three reactors was measured every day for 40 days, and the results are shown in Figure 3.

According to Figure 3, it can be found that when the influent is replaced with circuit board comprehensive wastewater, reactor 1 and reactor 2 continue to operate, and reactor 1 shows better denitrification and denitrification capacity than reactor 2. This shows that under the condition of treating circuit board comprehensive wastewater, the reactor using sulfur autotrophic denitrification filler 1 can have better denitrification capacity.

Example 6

The reactor in Example 5 was taken to continue the test. The test water remained unchanged, and potassium nitrate was added to the water to further increase the nitric nitrogen concentration. The final influent water quality had a pH of 8.0-9.5, a nitric nitrogen concentration of 250 mg/L, an ammonia nitrogen concentration of 1.5 mg/L, and a total phosphorus concentration of 1 mg/L by adding potassium dihydrogen phosphate. The influent alkalinity was adjusted to 1000 mg/L by adding sodium bicarbonate, and the hydraulic retention time was 12 h.

The nitric nitrogen in the three reactors was measured regularly. The results are shown in Figure 4 after 40 days of operation.

According to the data in Figure 4, it can be found that under the condition of increasing the nitrate-nitrogen concentration in the influent, the denitrification effect of reactor 1 is significantly higher than that of reactor 2. This is because the specific surface area, surface roughness and solid-liquid contact area of the traditional sulfur block filler are relatively low. In addition, the hydraulic balance of the traditional sulfur block filler is difficult, and short-flow is prone to occur in long-term operation. The sulfur autotrophic denitrification filler 1 of the present invention has made improvements to these limitations. Therefore, the upper limit of the denitrification volumetric load of the sulfur autotrophic denitrification filler 1 of the present invention is higher, and a higher denitrification capacity can still be retained when facing high nitrate-nitrogen load influent.

Example 7

Sludge samples from the two reactors in Example 4, Example 5 and Example 6 were taken for high-throughput sequencing to determine the characteristics of the microbial community, and the biological sampling time was 0 day, 80 days, 120 days and 160 days, respectively.

As shown in Figure 5, the main bacterial phyla occupied by the sludge initially inoculated in reactor 1 and reactor 2 are Proteobacteria, Bacteroidota, Firmicutes and Deinococcota. The sludge initially falls into the filler in the reactor as much as possible. After a period of reaction, Campylobacterota begins to appear, and the relative abundance of Campylobacterota in reactor 1 is 22.03% and 46.36% on the 120th and 160th days. Campylobacter is related to sulfur autotrophic denitrifying bacteria, indicating that after being domesticated by sulfur autotrophic denitrification filler 1, sulfur autotrophic denitrifying bacteria show strong biological competitiveness and obtain ecological niche advantages, indicating that sulfur autotrophic denitrification filler 1 has excellent sulfur autotrophic microbial affinity. At the same time, after acclimation, the relative abundance of Firmicutes began to decrease significantly, indicating that Firmicutes was inhibited. This may be due to the low C/N ratio and the strong microbial selectivity on the surface of sulfur autotrophic denitrification filler 1. This selectivity is due to the sulfur cycle involved in the sulfur autotrophic denitrification reaction, which will form a higher concentration of sulfur ions on the microscopic surface of the filler, which is inhibitory to some microorganisms.

On the other hand, it can be seen from Figure 6 that the microbial genus level of reactor 1 is mainly Sulfurimonas, Limnobacter, Lentimicrobium, Sporosarcina, Truepera and Tissierella. Sulfurimonas is a common sulfur autotrophic denitrifying bacteria genus. After short-term domestication, the relative abundance of Sulfurimonas increased from undetected at the beginning to 20% on the 80th day, and its relative abundance continued to increase subsequently, indicating that the reactor 1 has continuously occupied a large number of ecological niches through the action of sulfur autotrophic denitrification filler 1 and has become a significantly dominant genus.

Finally, through the analysis of the microbial community, it can be known that the sulfur autotrophic denitrifying filler prepared by the present invention has the ability to quickly domesticate sulfur autotrophic denitrifying bacteria in situ, and the sulfur autotrophic denitrifying filler can be used continuously for at least 160 days after being put into use once, and its related sulfur autotrophic denitrifying bacteria show a continuously increasing ecological niche advantage, which is consistent with the denitrification ability performance of Examples 4 to 6.

The embodiments of the present invention are described in detail above, but the present invention is not limited to the described embodiments. For those skilled in the art, various changes, modifications, substitutions and variations of these embodiments are made without departing from the principles and spirit of the present invention, and still fall within the protection scope of the present invention.

Claims (7)

1. The sulfur autotrophic denitrification filler is characterized in that the preparation raw materials comprise: sulfur powder, iron white powder, aluminum hydroxide powder, lignocellulose, anionic polyacrylamide, sepiolite and porous resin;

The porous resin is PVC porous resin;

The mass ratio of the sulfur powder to the iron white powder to the aluminum hydroxide powder to the lignocellulose is (2.5-3.5): (0.5-1.5): (0.1-0.2): (0.01-0.05); the mass ratio of the anionic polyacrylamide to the sepiolite is (1-3): 2-4; the mass ratio of the sulfur powder to the anionic polyacrylamide is 3: (0.02-0.06).

2. The sulfur autotrophic denitrification filler according to claim 1, wherein the particle size of the sulfur powder is not less than 300 meshes, the particle size of the iron white powder is not less than 200 meshes, the particle size of the aluminum hydroxide powder is not less than 200 meshes, and the length of the lignocellulose is 1-3 mm.

3. The sulfur autotrophic denitrification filler of claim 1, wherein the sepiolite has a particle size of 2-4 mm.

4. A process for the preparation of a sulfur autotrophic denitrification filler as defined in any one of claims 1-3, comprising the steps of:

(1) Mixing sulfur powder, iron white powder, aluminum hydroxide powder and lignocellulose to obtain a mixed dry material;

(2) Mixing and stirring anionic polyacrylamide, sepiolite particles and water to obtain an adhesion protective agent;

(3) Adding the adhesion protective agent into the mixed dry material, uniformly mixing, kneading and stirring to obtain a mixed wet material;

(4) And adding the mixed wet material into porous resin, extruding and kneading, taking out, draining, and drying to obtain the sulfur autotrophic denitrification filler.

5. The method for preparing sulfur autotrophic denitrification filler according to claim 4, wherein in the step (3), the usage ratio of the adhesion protecting agent to the mixed dry material is (50-100) mL: (100-150 g).

6. The method for preparing a sulfur autotrophic denitrification filler according to claim 4, wherein in the step (4), the amount of the mixed wet material is 1dm ³ of porous resin added (800-1200 mL of mixed wet material).

7. The method for producing a sulfur autotrophic denitrification filler as claimed in claim 4, wherein in the step (4), the temperature of the drying is not more than 42 ℃.