Preparation method of porous sulfur mineral autotrophic denitrification material and application thereof in black and odorous water purification

Abstract

The application discloses a preparation method of a porous sulfur mineral autotrophic denitrification material and application of the material in black and odorous water purification. The porous sulfur mineral functional material is prepared by using coral, iron-manganese oxide minerals and sulfur minerals, so that waste is reused, resources are saved, and the preparation method is simple; on the other hand, the porous sulfur mineral functional material has a large specific surface area and high activity. The high-activity porous sulfur mineral functional material can be used as an electron donor of sulfur autotrophic denitrification bacteria and denitrifying sulfur bacteria in a black and odorous water body with a low carbon-nitrogen ratio. Meanwhile, the coral, iron-manganese oxide minerals, nano zero-valent calcium and nano zero-valent iron-manganese formed by hydrogen reduction roasting, and the hydrated silicate formed by the sulfur mineral and cement improve the alkalinity in the reaction system, can neutralize the sulfur autotrophic denitrification acid production process, and realize deep purification of the black and odorous water body.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of sewage treatment, and particularly relates to a method for preparing porous sulfur function material from coral, iron-manganese oxide mineral, cement and sulfur mineral as raw materials and application of the porous sulfur function material in black and odorous water purification. BACKGROUND

[0002] With the rapid advancement of urbanization in China, a large amount of pollutants are concentratedly generated and discharged. Untreated or substandard domestic sewage, industrial wastewater and the like enter rivers, so that pollutants are continuously accumulated, the dissolved oxygen content is decreased, the chemical oxygen demand and the concentrations of nitrogen and phosphorus pollutants are increased, and the water quality of the water body is deteriorated. Black and odorous is an extreme phenomenon of a water body being seriously polluted, which not only destroys the urban landscape, but also causes the water body to lose ecological function and harm human health. According to the magnitude of the characteristic indexes (transparency, dissolved oxygen, oxidation-reduction potential, phosphorus and ammonia nitrogen) of the water body, the polluted water body can be divided into two categories of mild black and odorous and severe black and odorous. It is found that the main cause of the black and odorous water body is the excessive discharge of nitrogen and phosphorus, and therefore, how to deeply remove nitrogen and phosphorus in the black and odorous water body with a low carbon-nitrogen ratio (C / N) is a key technical problem to be solved for purifying the black and odorous water body.

[0003] Sulfur autotrophic denitrification technology is a kind of biological denitrification technology, and its research is earliest originated from the 1970s of the 20th century. The technology mainly utilizes denitrifying sulfur bacteria to oxidize sulfide into sulfate, while carrying out denitrification, so as to realize the removal of nitrogen. The technology uses sulfide as an electron donor to realize denitrification under anaerobic conditions, without the need of adding carbon. Compared with other autotrophic denitrification technologies, the technology has the characteristics of being cheap and easy to obtain, less affected by water quality, and easy to be utilized. Since the sulfur autotrophic denitrification process includes the oxidation of S and the reduction of N, the technology also has considerable potential in the aspect of waste resource utilization. At present, the sulfur autotrophic denitrification technology is mainly applied in the field of deep denitrification, and replaces the traditional heterotrophic denitrification filter. The sulfur autotrophic denitrification has the advantages of not needing to add carbon source, saving the consumption of carbon source, no secondary pollution, less sludge production, etc., and has no problem of carbon source penetration, and can prevent the increase of the COD of effluent, so the technology becomes a hot spot in the field of denitrification, and is regarded as one of the best technologies for treating low C / N wastewater and replacing the traditional heterotrophic denitrification process.

[0004] At present, the sulfur autotrophic denitrification mainly uses elemental sulfur, sulfur mineral composite siderite, pyrite, sulfur mineral composite gypsum, pyrrhotite, sulfur paste, hematite composite pyrolytic pyrite, sodium sulfide, sodium thiosulfate and other reduced sulfur sources as electron donors, CO3 2- , HCO3 - , CO2 as inorganic carbon sources, and NO3 --N is reduced to N2. Sodium sulfide and sodium thiosulfate are expensive, which will cause economic burden to enterprises. Pyrite (pyrite, pyrrhotite) is rich in the earth's crust and low in price, and can be used as an electron donor. However, the density of pyrite is much greater than that of sulfur, which is not easy to be utilized by microorganisms in sewage, and will make the reactor start slowly and the denitrification performance poor. In addition, the biofilm with pyrite as filler is easy to block the pyrite, which reduces the efficiency of denitrification and phosphorus removal, and frequent backwashing is required, which increases the cost. Therefore, the development of cheap, porous and light porous sulfur functional materials is the key to solving the above problems. SUMMARY

[0005] The application provides a preparation method of porous sulfur functional material and application of the porous sulfur functional material in black and odorous water purification treatment, so as to solve the problems of low porosity, small specific surface area, low activity and poor stability of the existing autotrophic denitrification filler, further strengthen the activity of sulfur mineral, shorten the hydraulic retention time, improve the nitrogen and phosphorus removal efficiency, and enhance the purification effect of black and odorous water.

[0006] The coral is in the form of microcrystalline calcite (CaCO3) and contains organic matter. The coral has a porous structure, and mainly includes dendritic shape. The color of the coral is often blue, white and red. The coral has a porous structure, is suitable for being used as a carrier of sulfur autotrophic denitrification bacteria and denitrifying sulfur bacteria, is beneficial to growth and reproduction of the bacteria, improves the mass transfer efficiency, and can improve the denitrification efficiency. It is found that the coral can effectively adsorb heavy metals such as lead, mercury, arsenic and cadmium, and purify water quality. Recent research shows that the nano zero-valent composite functional material mainly composed of nano zero-valent calcium is formed by pyrolysis of the coral through hydrogen reduction. The nano zero-valent composite functional material slowly releases calcium ions in the water environment, so that the pH value of the water environment can be maintained at 7-8.5, and the phosphorus in the black and odorous water body can be effectively fixed.

[0007] The natural iron-manganese oxide mineral has surface charge and contains variable valence elements, and is an important nanomineral resource. The iron-manganese oxide mineral belongs to the spinel mineral family, is a metamorphic primary phase mineral, and is produced in the metamorphic process of the manganese-containing stratum. The iron-manganese oxide mineral can react with phenolic compounds to repair environmental pollution. Previous research shows that the iron-manganese oxide mineral can generate nano zero-valent iron-manganese composite material after being calcined in a hydrogen atmosphere. The composite material has a large specific surface area and high activity, and the zero-valent iron and manganese have a synergistic effect, which improves the removal capacity of pollutants.

[0008] The present application adopts coral with porous structure, iron manganese oxide mineral as raw material, mixes according to certain proportion, and can form nano zero-valent iron manganese composite material after hydrogen reduction roasting, nano zero-valent calcium, and is compounded with sulfur mineral and cement, through steam curing, prepares porous sulfur functional material. The porous sulfur functional material can be used as the electron donor of sulfur autotrophic denitrifying bacteria and denitrifying sulfur bacteria, and the nano zero-valent calcium and nano zero-valent iron manganese composite material can effectively fix phosphorus in black and odorous water. Meanwhile, the nano zero-valent iron manganese composite material releases iron manganese ions and cooperates with sulfur mineral to act as electron donor, promotes the activity of denitrifying sulfur bacteria, and then realizes the synchronous removal of nitrogen and phosphorus.

[0009] The preparation method of the porous sulfur functional material comprises the following steps:

[0010] Step 1: pretreat sulfur mineral and iron manganese oxide mineral, pass through a 200-mesh sieve to obtain sulfur mineral powder and iron manganese oxide mineral powder; crush coral to obtain cylindrical coral granules with a length of 1-3 cm and a diameter of 3-6 mm; the sulfur content of the sulfur mineral is more than 95%, the iron content of the iron manganese oxide mineral is 20-60%, and the manganese content is 30-40%.

[0011] Step 2: immerse the coral in water to form a water film on the coral, and then spray the iron manganese oxide mineral powder into the inner and outer pores of the coral, so that the inner and outer pores of the coral are filled with the iron manganese oxide mineral powder; the mass ratio of the coral to the iron manganese oxide mineral powder is 10:1-3.

[0012] Step 3: place the composite obtained in step 2 in a hydrogen atmosphere and roast, so that the iron manganese oxide mineral powder is loaded in the pore structure of the coral to form nano zero-valent iron manganese composite coral granules.

[0013] Step 4: spray the nano zero-valent iron manganese composite coral granules obtained in step 3 with sulfur mineral powder and cement, and perform steam curing to obtain high-activity sulfur-based nano zero-valent iron manganese composite coral porous material, i.e., porous sulfur functional material. The cement is one or a combination of several of 42.5, 52.5 and 62.5.

[0014] In step 3, the roasting temperature is 500-1000 DEG C, and the roasting time is 1-5 h. The roasting atmosphere is hydrogen. The roasting temperature is a key factor affecting the specific surface area and porosity. Roasting removes the chemical state water (adsorbed water, crystal water, interlayer water, zeolite water and structural water) of the coral and the iron manganese oxide mineral, and further improves the specific surface area and porosity of the nano zero-valent iron manganese composite coral granules.

[0015] In step 4, the spraying amount of the nano zero-valent iron manganese composite coral granules, sulfur powder and cement is 10:3-8:1-3 in mass ratio.

[0016] In step 4, the autoclaving temperature is ≤300℃, the autoclaving pressure is 1-10 MPa, and the autoclaving curing time is 5-48 hours.

[0017] The specific surface area of the porous sulfur functional material is 300-600 m 2 / g, and the porosity is 90-100%.

[0018] Application of the porous sulfur functional material in deep purification treatment of black and odorous water bodies.

[0019] Specifically, the porous sulfur functional material is used as a carrier and an electron donor of sulfur autotrophic denitrifying bacteria and denitrifying sulfur bacteria, nitrogen and phosphorus are simultaneously removed in an anaerobic process, and deep purification of black and odorous water bodies is achieved.

[0020] The high-activity porous sulfur mineral functional material has a high reducibility group on the surface, high activity and adsorption performance, can realize efficient purification treatment of black and odorous water bodies, and the water treatment process is simple and convenient.

[0021] The porous sulfur mineral functional material is prepared from coral, iron-manganese oxide mineral, sulfur mineral and cement, which realizes waste reuse, saves resources and has a simple preparation method. The porous sulfur mineral functional material has a large specific surface area and high activity, can be used as an electron donor of sulfur autotrophic denitrifying bacteria and denitrifying sulfur bacteria in a black and odorous water body with a low carbon-nitrogen ratio, and the coral and iron-manganese oxide mineral form nano zero-valent calcium, nano zero-valent iron and manganese after hydrogen reduction roasting, and the sulfur mineral and cement form hydrated silicate after hydration, which improves the alkalinity of the water body, neutralizes the acid production process of sulfur autotrophic denitrification, and on the other hand, the activity of the sulfur mineral is improved in the autoclaving process at high temperature and high pressure, the electron transfer rate is accelerated, and the activity of the biological enzyme of the denitrifying sulfur bacteria is improved. The porous sulfur mineral can effectively fix phosphorus ions in the black and odorous water body, simultaneously remove nitrogen and phosphorus, and is very suitable for application in treatment of black and odorous water bodies with a low carbon-nitrogen ratio. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 The XRD pattern of the hydrogen reduction roasting iron-manganese oxide mineral is shown in Figure 2. Figure 1 It can be seen that the nano zero-valent iron and manganese have strong characteristic diffraction peaks, high crystallinity and high activity.

[0023] Figure 2 The XRD pattern of the porous sulfur mineral functional material of Example 1 is shown in Figure 3. Figure 2The characteristic diffraction peaks of nano zero-valent calcium, nano zero-valent iron-manganese and elemental sulfur can be seen, which shows that the porous sulfur ore mineral functional material is a functional material mainly composed of nano zero-valent calcium, nano zero-valent iron-manganese and high-activity sulfur ore mineral.

[0024] Figure 3 The XRD pattern of the porous sulfur ore mineral functional material of Example 2 is shown in Figure 2. Figure 3 The characteristic diffraction peaks of nano zero-valent calcium, nano zero-valent iron-manganese and elemental sulfur can be seen, which shows that the porous sulfur ore mineral functional material is a functional material mainly composed of nano zero-valent calcium, nano zero-valent iron-manganese and high-activity sulfur ore mineral.

[0025] Figure 4 The XRD pattern of the porous sulfur ore mineral functional material of Example 3 is shown in Figure 3. Figure 4 The characteristic diffraction peaks of nano zero-valent calcium, nano zero-valent iron-manganese and elemental sulfur can be seen, which shows that the porous sulfur ore mineral functional material is a functional material mainly composed of nano zero-valent calcium, nano zero-valent iron-manganese and high-activity sulfur ore mineral.

[0026] Figure 5 The XRD pattern of the porous sulfur ore mineral functional material of Example 4 is shown in Figure 4. Figure 5 The characteristic diffraction peaks of nano zero-valent calcium, nano zero-valent iron-manganese and elemental sulfur can be seen, which shows that the porous sulfur ore mineral functional material is a functional material mainly composed of nano zero-valent calcium, nano zero-valent iron-manganese and high-activity sulfur ore mineral.

[0027] Figure 6 The SEM pattern of the coral is shown in Figure 5 (A, B, C and D are different magnifications). Figure 6 The coral has a porous structure and a large pore structure connected inside and outside, and under a higher magnification, it can be clearly seen that it has nano particles.

[0028] Figure 7 The SEM pattern of the iron-manganese oxide mineral is shown in Figure 6 (A, B, C and D are different magnifications). Figure 7 The iron-manganese oxide mineral has a natural nano structure and an irregular pore structure, and after hydrogen reduction pyrolysis, a nano zero-valent iron-manganese composite material with nano structure is further formed.

[0029] Figure 8 The SEM pattern of the sulfur ore mineral is shown in Figure 7 (A, B, C and D are different magnifications). Figure 8 It can be seen that the sulfur ore mineral has a dense structure and a low porosity, and the activity is low.

[0030] Figure 9 The SEM pattern of the cement is shown in Figure 8 (A, B, C and D are different magnifications). Figure 9It can be seen that the cement has a porous structure, showing a petal-shaped nano-porous structure, because the cement generates hydrated silicate aluminate and C-S-H gel after carbonization in air.

[0031] Figure 10 The SEM images of the porous sulfur-sulfur mineral functional material of Example 1 (A, B, C, D, and E are different magnifications) are shown in Figure 1. Figure 10 It can be seen that the porous sulfur-sulfur mineral functional material has a large pore structure, because the nano-structure is formed after hydrogen reduction roasting, and this porous structure can provide living space for sulfur autotrophic denitrifying bacteria, Thiobacillus denitrificans, improve the biological load, promote the simultaneous removal of nitrogen and phosphorus, and deeply purify the black and odorous water body.

[0032] Figure 11 The SEM images of the porous sulfur-sulfur mineral functional material of Example 2 (A, B, C, D, and E are different magnifications) are shown in Figure 2. Figure 11 It can be seen that the porous sulfur-sulfur mineral functional material has a large pore structure, because the nano-structure is formed after hydrogen reduction roasting, and this porous structure can provide living space for sulfur autotrophic denitrifying bacteria, Thiobacillus denitrificans, improve the biological load, promote the simultaneous removal of nitrogen and phosphorus, and deeply purify the black and odorous water body.

[0033] Figure 12 The physical images of various materials are shown in Figure 3. Among them: (A) white coral; (B) white coral particles; (C) porous sulfur-sulfur mineral functional material; (D) sulfur-sulfur mineral; (E) red coral; (F) iron-manganese oxide mineral; (G) blue coral.

[0034] Figure 13 The FISH images of the microorganisms in the bioreactor in Examples 1-4 (A, B, C, D, E, F, G, H, and J are different biological samples taken from the sulfur autotrophic denitrifying biofilter) are shown in Figure 4. Figure 13 It can be seen that in Examples 1-4, there are a large number of sulfur autotrophic denitrifying bacteria, Thiobacillus denitrificans, which can efficiently purify the black and odorous water body. DETAILED DESCRIPTION

[0035] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific embodiments of the present application will be described in detail below with reference to the accompanying drawings.

[0036] Example 1

[0037] The preparation method of the high-activity porous sulfur-sulfur mineral functional material in this embodiment includes the following steps:

[0038] 1. Pretreat sulfur mineral and iron-manganese oxide mineral, grind through 200 mesh sieve, obtain sulfur mineral powder and iron-manganese oxide mineral powder; crush red coral, obtain cylindrical red coral granular material, length is 2 cm, diameter is 4 mm; sulfur content of sulfur mineral is 95%, iron content of iron-manganese oxide mineral is 60%, manganese content is 40%;

[0039] 2. Soak red coral in water, make red coral form water film, spray iron-manganese oxide mineral powder, make inner and outer pore channel of red coral be filled with iron-manganese oxide mineral powder; mass ratio of red coral to iron-manganese oxide mineral powder is 10:1;

[0040] 3. Place compound obtained in step 2 in hydrogen reduction atmosphere, bake at 500 DEG C, baking time is 1 hour, then condense in hydrogen atmosphere, form red coral based nanometer zero-valent iron-manganese compound;

[0041] 4. Spray cement, sulfur mineral powder to red coral based nanometer zero-valent iron-manganese compound, mass ratio of red coral based nanometer zero-valent iron-manganese compound to sulfur mineral powder to cement is 10:5:1, mark number of cement is 42.5, high temperature autoclaving, temperature is 150 DEG C, pressure is 2 MPa, autoclaving time is 24 hours, obtain porous sulfur mineral functional material. Specific surface area of the compound is 351 m 2 / g, porosity is 98%.

[0042] Example 2

[0043] Preparation method of high activity porous sulfur mineral functional material in the embodiment includes following steps:

[0044] 1. Pretreat sulfur mineral and iron-manganese oxide mineral, grind through 200 mesh sieve, obtain sulfur mineral powder and iron-manganese oxide mineral powder; obtain cylindrical coral granular material, length is 3 cm, diameter is 5 mm; sulfur content of sulfur mineral is 96%, iron content of iron-manganese oxide mineral is 50%, manganese content is 50%;

[0045] 2. Soak blue coral in water, make blue coral form water film, spray iron-manganese oxide mineral powder, make inner and outer pore channel of blue coral be filled with iron-manganese oxide mineral powder; mass ratio of blue coral to iron-manganese oxide mineral powder is 10:3;

[0046] 3. Place compound obtained in step 2 in hydrogen reduction atmosphere, bake at 600 DEG C, baking time is 2 hours, then condense in hydrogen atmosphere, form blue coral based nanometer zero-valent iron-manganese compound;

[0047] 4. Spraying cement and sulfur powder on the white coral based nano zero-valent iron-manganese compound, wherein the mass ratio of the white coral based nano zero-valent iron-manganese compound, cement and sulfur powder is 10:7:2, the grade of the cement is 62.5, and high temperature and pressure steaming is performed at a temperature of 250 ℃ and a pressure of 6 MPa for 24 hours to obtain the porous sulfur mineral functional material. The specific surface area of the composite material is 527 m2 / g, and the porosity is 98%. 2 / g, and the porosity is 94%.

[0048] Example 3

[0049] The preparation method of the high-activity porous sulfur mineral functional material in this example includes the following steps:

[0050] 1. Pre-treating sulfur mineral and iron-manganese oxide mineral, grinding through a 200 mesh sieve to obtain sulfur mineral powder and iron-manganese oxide mineral powder; crushing white coral to obtain cylindrical white coral granular material with a length of 3 cm and a diameter of 4 mm; the sulfur content of the sulfur mineral is 97%, the iron content of the iron-manganese oxide mineral is 60%, and the manganese content is 40%;

[0051] 2. Soaking the white coral in water to form a water film, and spraying the iron-manganese oxide mineral powder to fill the inner and outer channels of the white coral with the iron-manganese oxide mineral powder; wherein the mass ratio of the white coral to the iron-manganese oxide mineral powder is 10:3;

[0052] 3. Placing the compound obtained in step 2 in a hydrogen reduction atmosphere and calcining at 700 ℃ for 3 hours, and then condensing in a hydrogen atmosphere to form a white coral based nano zero-valent iron-manganese compound;

[0053] 4. Spraying cement and sulfur powder on the white coral based nano zero-valent iron-manganese compound, wherein the mass ratio of the white coral based nano zero-valent iron-manganese compound, cement and sulfur powder is 10:7:2, the grade of the cement is 62.5, and high temperature and pressure steaming is performed at a temperature of 250 ℃ and a pressure of 6 MPa for 24 hours to obtain the porous sulfur mineral functional material. The specific surface area of the composite material is 527 m2 / g, and the porosity is 98%. 2 / g, and the porosity is 98%.

[0054] Example 4

[0055] The preparation method of the high-activity porous sulfur mineral functional material in this example includes the following steps:

[0056] 1. Pre-treating sulfur mineral and iron-manganese oxide mineral, grinding through a 200 mesh sieve to obtain sulfur mineral powder and iron-manganese oxide mineral powder; crushing white coral to obtain cylindrical white coral granular material with a length of 3 cm and a diameter of 4 mm; the sulfur content of the sulfur mineral is 97%, the iron content of the iron-manganese oxide mineral is 60%, and the manganese content is 40%;

[0057] 2. Soaking the blue coral in water to form a water film on the blue coral, and spraying the iron-manganese oxide mineral powder to fill the inner and outer pores of the blue coral with the iron-manganese oxide mineral powder; wherein the mass ratio of the blue coral to the iron-manganese oxide mineral powder is 5:1;

[0058] 3. Placing the compound obtained in step 2 in a hydrogen reduction atmosphere and calcining at 800℃ for 4 hours, and then condensing in a hydrogen atmosphere to form a blue coral-based nanometer zero-valent iron-manganese compound;

[0059] 4. Spraying the blue coral-based nanometer zero-valent iron-manganese compound with cement and sulfur mineral powder, wherein the mass ratio of the blue coral-based nanometer zero-valent iron-manganese compound, the cement, and the sulfur mineral powder is 10:3:3, the cement has a grade of 62.5, and high-temperature autoclaving is performed at a temperature of 300℃ and a pressure of 10 MPa for 48 hours to obtain a porous sulfur mineral functional material, the specific surface area of the compound being 589 m 2 / g and the porosity being 95%.

[0060] Comparative Example

[0061] 1. Coral sample preparation: Blue coral, white coral, and red coral were taken and broken to obtain coral granules with a length of 3 cm and a diameter of 5 mm for use, the average specific surface area of the corals being 250 m 2 / g and the average porosity being 82%.

[0062] 2. Hydrogen reduction calcination of coral sample preparation: Blue coral, white coral, and red coral were taken and broken to obtain granules with a length of 3 cm and a diameter of 5 mm, which were calcined in a hydrogen reduction atmosphere at a calcination temperature of 600℃ for 2 hours, the average specific surface area of the hydrogen reduction calcined corals being 310 m 2 / g and the average porosity being 97%.

[0063] 3. Pyrite sample preparation: Pyrite was taken and broken to obtain granules with a particle size of about 2-3 cm, the specific surface area of the pyrite being 0 m 2 / g and the porosity being 8%.

[0064] 4. Nanostructured pyrrhotite sample preparation: Pyrite was taken and broken to obtain granules with a particle size of about 2-3 cm for use, and pyrolysis was performed under a nitrogen protective atmosphere at a temperature of 700℃ for 2 hours, the specific surface area of the nanostructured pyrrhotite being 0 m 2 / g and the porosity being 10%.

[0065] 5. Sulfur mineral sample preparation: Sulfur mineral was taken and broken to obtain granules with a particle size of about 2-3 cm, the specific surface area of the sulfur mineral being 0 m 2 / g, porosity 2%.

[0066] 6, Iron-manganese oxide mineral sample preparation: Iron-manganese oxide mineral was crushed to obtain granular material with a particle size of 2-3 cm. The specific surface area of the iron-manganese oxide mineral was 10 m 2 / g, porosity 24%.

[0067] 7, Hydrogen reduction roasting iron-manganese oxide mineral sample preparation: Iron-manganese oxide mineral was crushed to obtain granular material with a particle size of 2-3 cm. The iron-manganese oxide mineral granular material was reduced and roasted under hydrogen, the roasting temperature was 700°C, the roasting time was 3 hours, and the specific surface area of the nano zero-valent iron-manganese composite material was 27 m 2 / g, porosity 35%.

[0068] 8, Sulfur paste sample preparation: Sulfur paste was granulated into 2-3 cm granules for use, and naturally air-dried. The specific surface area of the sulfur paste granular material was 0 m 2 / g, porosity 7%.

[0069] Dynamic test process of examples 1-4 and comparative examples 1-8:

[0070] Anaerobic biofilter dynamic treatment of simulated low-concentration nitrate nitrogen and phosphorus black and odorous water was carried out. The filler samples of examples 1-4 and comparative examples 1-8, in which the sample was filled with 40 kg as the biological carrier material of sulfur autotrophic denitrifying bacteria and denitrifying sulfur bacteria, were used. These fillers were respectively filled in 12 anaerobic biofilter reactors (mainly made of organic glass) with the same size, in which the biofilter reactor was 2.6 m high, the outer diameter was 0.5 m, the inner diameter was 0.5 m, and the effective volume of the anaerobic biofilter reactor was 0.5 m 3 The filling height of the sample was 2.5 m to investigate the purification effect of black and odorous water of the filler samples of examples 1-4 and comparative examples 1-8. The black and odorous sewage entered from the bottom of the anaerobic biofilter reactor and flowed out from the top outlet of the anaerobic biofilter reactor. A sewage tank filled with black and odorous water was placed beside each anaerobic biofilter reactor, and the black and odorous water flowed into the anaerobic biofilter reactor through a peristaltic pump, and the hydraulic retention time was controlled through the peristaltic pump. The outlet was connected to the sewage network through a rubber tube. The simulated black and odorous water was prepared by using sodium nitrate to configure NO3 - -N with a concentration of 80 mg / L and potassium dihydrogen phosphate to configure phosphorus with a concentration of 1 mg / L, the hydraulic retention time was 1 hour, the temperature was 25°C, and the continuous operation was carried out for 90 days. The concentrations of total nitrogen and total phosphorus in the inlet and outlet water were monitored respectively.

[0071] As can be seen from Tables 1-4, the porous sulfur functional materials prepared in Examples 1-4 have better purification effect on black and odorous water than the samples prepared in Comparative Examples 1-8, wherein the effluent after purification by the porous sulfur functional materials prepared in Examples 1-4 can reach the standard of surface water of Class III. This is because the porous sulfur mineral functional materials prepared in Examples 1-4 have large specific surface area, high porosity, and high-activity sulfur minerals uniformly distributed on the inner and outer surfaces of the corals, and the sulfur autotrophic denitrifying bacteria and denitrifying thiobacillus can enter the interior of the porous sulfur mineral functional materials from the open pores thereof to reproduce and grow, thereby improving the denitrification efficiency. On the other hand, the nano zero-valent iron-manganese composite material formed by hydrogen reduction of the iron-manganese oxide mineral can also act as an electron donor to promote denitrification, and cooperates with the high-activity sulfur mineral to promote denitrification. More importantly, the nano zero-valent calcium, nano zero-valent iron-manganese composite material, and hydrated silicate cement can effectively fix phosphorus in the black and odorous water to form hydroxyapatite and iron phosphate precipitates, achieve simultaneous denitrification and phosphorus removal, and achieve deep purification of the black and odorous water. As shown in the following Figure 13 The FISH molecular biology analysis observation of (A-J) shows that the sulfur autotrophic denitrifying bacteria and denitrifying thiobacillus exist in Examples 1-4, because Examples 1-4 have high activity to promote the growth and reproduction of the sulfur autotrophic denitrifying bacteria and denitrifying thiobacillus, and can efficiently and deeply purify the black and odorous water.

[0072] As can be seen from Comparative Examples 1 and 2, the coral particulate matter and the hydrogen-reduced calcined coral particulate matter have large specific surface area, and the coral does not contain sulfur element, so the removal rates of nitrogen and phosphorus in the black and odorous water are low. The specific surface area of the pyrite and the pyrolyzed pyrite in Comparative Examples 3 and 4 is small, the porosity is low, and the density is large, so the purification effect on the black and odorous water is poor, and the backwashing effect is poor. As can be seen from Comparative Example 5, the specific surface area of the sulfur mineral is small, the porosity is low, and the efficiency on the black and odorous water is also poor, because the natural sulfur mineral has compact structure and low mass transfer efficiency of released sulfur ions. The specific surface area of the iron-manganese oxide mineral, the nano zero-valent iron-manganese composite material, and the sulfur paste in Comparative Examples 6, 7, and 8 is small, the porosity is low, and the purification efficiency on the black and odorous water is also low. As can be seen from the above analysis, Examples 1-4 have high treatment efficiency on nitrogen and phosphorus, can deeply purify the black and odorous water, and can be applied and popularized on a large scale.

[0073] Table 1 Removal rate of total nitrogen by Examples 1-4

[0074] Reaction run time (d) Example 1 Example 2 Example 3 Example 4 5 52％ 43％ 38％ 48％ 10 61％ 65％ 69％ 59％ 20 70％ 71％ 72％ 76％ 25 81％ 80％ 84％ 86％ 30 95％ 99％ 97％ 90％ 35 100％ 100％ 100％ 100％ 40 100％ 100％ 100％ 100％ 45 100％ 100％ 100％ 100％ 50 100％ 100％ 100％ 100％ 55 100％ 100％ 100％ 100％ 60 100％ 100％ 100％ 100％ 65 100％ 100％ 100％ 100％ 70 100％ 100％ 100％ 100％ 75 100％ 100％ 100％ 100％ 80 100％ 100％ 100％ 100％ 85 100％ 100％ 100％ 100％ 90 100％ 100％ 100％ 100％

[0075] Table 2 Removal rate of total phosphorus by Examples 1-4

[0076] Reaction run time (d) Example 1 Example 2 Example 3 Example 4 5 100％ 100％ 100％ 100％ 10 100％ 100％ 100％ 100％ 20 100％ 100％ 100％ 100％ 25 100％ 100％ 100％ 100％ 30 100％ 100％ 100％ 100％ 35 100％ 100％ 100％ 100％ 40 100％ 100％ 100％ 100％ 45 100％ 100％ 100％ 100％ 50 100％ 100％ 100％ 100％ 55 100％ 100％ 100％ 100％ 60 100％ 100％ 100％ 100％ 65 100％ 100％ 100％ 100％ 70 100％ 100％ 100％ 100％ 75 100％ 100％ 100％ 100％ 80 100％ 100％ 100％ 100％ 85 100％ 100％ 100％ 100％ 90 100％ 100％ 100％ 100％

[0077] Table 3 Removal rate of total nitrogen by Comparative Examples 1-8

[0078]

[0079]

[0080] Table 4 Removal rate of total phosphorus of Comparative Examples 1-8

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Claims

1. A method for preparing a porous sulfur mineral autotrophic denitrification material, characterized in that... Includes the following steps: Step 1: Pre-treat the sulfur minerals and iron-manganese oxide minerals by passing them through a 200-mesh sieve to obtain sulfur mineral powder and iron-manganese oxide mineral powder respectively; after crushing the coral, obtain cylindrical coral-like particles with a length of 1-3 cm and a diameter of 3-6 mm; the sulfur minerals contain more than 95% sulfur; the iron-manganese oxide minerals contain 20-60% iron and 30-50% manganese. Step 2: Soak the coral in water to form a water film, then spray iron-manganese oxide mineral powder into the inner and outer pores of the coral to fill the pores with iron-manganese oxide mineral powder. Step 3: The composite obtained in Step 2 is calcined in a hydrogen atmosphere, and the iron-manganese oxide mineral powder is loaded into the pore structure of the coral to form nano-zero-valent iron-manganese composite coral particles. Step 4: Spray sulfur mineral powder and cement onto the nano-zero-valent iron-manganese composite coral particles obtained in Step 3, and then steam-press curing to obtain highly active sulfur-based nano-zero-valent iron-manganese composite coral porous material, i.e. porous sulfur functional material.

2. The preparation method according to claim 1, characterized in that: In step 2, the mass ratio of coral to iron-manganese oxide mineral powder is 10:1-3.

3. The preparation method according to claim 1, characterized in that: In step 3, the roasting temperature is 500-1000℃ and the roasting time is 1h-5h.

4. The preparation method according to claim 1, characterized in that: In step 4, the mass ratio of the sprayed amount of the nano-zero-valent iron-manganese composite coral particles, sulfur mineral powder, and cement is 10:3-8:1-3.

5. The preparation method according to claim 4, characterized in that: In step 4, the cement grade is one or more of 42.5, 52.5, and 62.

5.

6. The preparation method according to claim 1, characterized in that: In step 4, the autoclaving temperature is ≤300℃, the autoclaving pressure is 1-10MPa, and the autoclaving time is 5-48 hours.

7. The preparation method according to claim 1, characterized in that: The specific surface area of ​​the porous sulfur functional material is 300-600 m². 2 / g, with a porosity of 90-100%.

8. The application of porous sulfur functional materials prepared by any one of the preparation methods in claims 1-7 in the deep purification treatment of black and odorous water bodies.

9. The application according to claim 8, characterized in that: Using the porous sulfur functional material as a carrier and electron donor for sulfur autotrophic denitrifying bacteria and denitrifying sulfur bacteria, nitrogen and phosphorus are removed simultaneously during the anaerobic process, thus achieving deep purification of black and odorous water bodies.

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