High-dissolved-oxygen-content constructed wetland system for removing sulfonamide antibiotics

Abstract

The utility model discloses a high-dissolved-oxygen-content constructed wetland system for removing sulfonamide antibiotics. The high-dissolved-oxygen-content constructed wetland system comprises a shell, a filler module and a water supply module, the filler module is mounted in the shell, and a water outlet is formed in the shell; the filler module sequentially comprises a vermiculite filler layer, a sludge biochar composite filler layer and a ceramsite filler layer from top to bottom, the thickness of the vermiculite filler layer, the thickness of the sludge biochar composite filler layer and the thickness of the ceramsite filler layer are 20-40 cm respectively, and wetland plants are planted in the vermiculite filler layer; according to the vertical flow constructed wetland system, vermiculite, composite sludge biochar and ceramsite are used as fillers of the constructed wetland, and the internal structure and porosity of the vertical flow constructed wetland system are changed by adjusting the combination mode of the fillers and setting the height of the fillers, so that the content of dissolved oxygen in the system is increased, the activity of microorganisms in the system is ensured, and the service life of the system is prolonged. The additional aeration process due to insufficient oxygen is reduced, and the removal efficiency of the vertical flow constructed wetland on various pollutants is improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of sewage treatment especially relates to a high dissolved oxygen content constructed wetland system for removing sulfonamide antibiotics. BACKGROUND

[0002] Constructed wetland is mainly composed of soil, plants, microorganisms, substrate and water body. The removal of pollutants in the water environment is mainly by substrate adsorption, plant absorption and microbial degradation, and the three work together. Compared with traditional secondary biochemical treatment technology, constructed wetland technology not only has the advantages of low energy consumption and low construction and maintenance cost, but also has better removal effect on trace pollutants such as antibiotics in sewage. The removal effect of constructed wetland system is mainly affected by factors such as system structure, substrate type, plant species, hydraulic load, residence time, as well as environmental factors such as pH, DO content, temperature and illumination.

[0003] The wetland substrate is not only the carrier for the growth of wetland plants, but also the environment for the growth and reproduction of microorganisms in the system. In constructed wetland, most of the physical and chemical reactions occur on the contact surface of the substrate. The accumulation of antibiotics in soil is significantly higher than that in zeolite and other substrates and plants, and the removal of antibiotic resistance genes is also affected by the properties of the substrate. Therefore, the adsorption capacity of the substrate is one of the important indicators affecting the efficiency of wetland remediation. In addition, the particle size selection, combination method and filling method of the constructed wetland filler are important factors affecting the removal efficiency of the constructed wetland in actual operation. At present, the main research of traditional substrate at home and abroad includes zeolite, quartz stone, activated carbon, sandy soil and the like. The traditional substrate filler has stable removal effect on traditional pollutants such as COD, TN, TP and ammonia nitrogen, but when the sewage contains special pollutants such as antibiotics, the removal effect of the traditional substrate filler is not good. With the wide application of antibiotics, which has the characteristics of hydrophilicity, difficulty in hydrolysis and persistence, it is gradually detected in large quantities. At the same time, sulfonamide antibiotics exist in the environment at low concentration for a long time, which poses a threat to the safety of the environment, ecology and human health. Therefore, it is necessary to improve the substrate of constructed wetland, adopt suitable combination method and operation method, so as to improve the removal efficiency of vertical flow constructed wetland for various pollutants.

[0004] In the existing technology, the dissolved oxygen content in the constructed wetland is insufficient to maintain the activity of microorganisms in the system, which leads to the removal effect of pollutants not reaching the expected value. In order to improve the removal effect of constructed wetland on special pollutants, aeration is used to increase the dissolved oxygen concentration in the system, so as to accelerate the degradation and conversion of microorganisms to pollutants. However, the aeration process consumes energy and increases the operation cost, and the aeration device may need subsequent maintenance and repair, which increases the maintenance difficulty and cost. Therefore, it is necessary to construct a constructed wetland system which is simple in operation, low in maintenance cost and has high removal effect on pollutants. UTILITY MODEL CONTENT

[0005] The utility model provides a kind of high dissolved oxygen content artificial wetland system for removing sulfonamide antibiotic, with low operating cost, the problem of insufficient dissolved oxygen content in artificial wetland is solved.

[0006] The utility model discloses a kind of high dissolved oxygen content artificial wetland system for removing sulfonamide antibiotic, with low operating cost, the problem of insufficient dissolved oxygen content in artificial wetland is solved.

[0007] A kind of high dissolved oxygen content artificial wetland system for removing sulfonamide antibiotic, including shell, filler module and water supply module;The filler module is installed in the inside of the shell, the shell is opened outlet;The filler module includes vermiculite filler layer, sludge biochar composite filler layer and ceramsite filler layer from top to bottom in turn, the thickness of the vermiculite filler layer, sludge biochar composite filler layer and the ceramsite filler layer is 20-40cm respectively, wetland plant is planted in the vermiculite filler layer, the sludge biochar composite filler layer is the filler layer that equal volume sludge biochar, river sand, ceramsite are uniformly mixed;

[0008] The water supply module includes peristaltic pump, inlet pipe, distribution pipe and water collecting pipe, the inlet pipe is connected with the

[0009] Peristaltic pump, one end of the distribution pipe is connected with the inlet pipe, the other end of the distribution pipe is connected with the vermiculite filler layer;The water collecting pipe includes first water collecting pipe, second water collecting pipe and third water collecting pipe, the first water collecting pipe is installed between the vermiculite filler layer and the sludge biochar composite filler layer, the second water collecting pipe is installed between the sludge biochar composite filler layer and the ceramsite filler layer, the third water collecting pipe is installed between the ceramsite filler layer and the shell.

[0010] Preferably, the first water collecting pipe, second water collecting pipe and third water collecting pipe include horn, 90° elbow and PVC pipeline respectively, the water inlet end of the PVC pipeline is connected with the horn through the 90° elbow, and the horn opens upward;The water outlet end of the PVC pipeline passes through the outlet of the shell and extends to the outside of the shell.

[0011] Preferably, the PVC pipeline is provided with a valve, and the valve is located outside the shell.

[0012] Preferably, the particle size of the sludge biochar is 4-6mm;The particle size of the river sand is 1-2mm;The particle size of the ceramsite is 4-6mm.

[0013] Preferably, the mass ratio of iron powder, sludge and kaolin in the sludge biochar is 1-6:2:5.

[0014] Preferably, the particle size of the ceramsite in the ceramsite filler layer is 10-20mm.

[0015] Preferably, the wetland plants include one or more of Acorus calamus, Phragmites australis, Typha latifolia and Juncus effusus.

[0016] Preferably, the first vermiculite filler layer has a vermiculite particle size of 5-10mm.

[0017] Preferably, the water distribution pipe is made of silica gel hose, and has a ring shape and a plurality of holes.

[0018] The present application has the following advantages and beneficial effects compared with the prior art.

[0019] (1) The present application uses vermiculite, composite sludge biochar and ceramsite as the filler of the constructed wetland, adjusts the combination mode of the filler and the height of the filler, changes the internal structure and porosity of the vertical flow constructed wetland system, thereby increasing the content of dissolved oxygen in the system, ensuring the activity of microorganisms in the system, reducing the process of additional aeration due to insufficient oxygen, and achieving the improvement of the removal efficiency of the vertical flow constructed wetland for various pollutants without additional energy consumption, and having the advantages of simple structure, low construction cost and low maintenance cost.

[0020] (2) The present application can not only remove conventional pollutants, but also effectively remove sulfonamide antibiotics. The composite sludge biochar filler layer contains iron, and the valence state of iron is variable, so that a micro-current environment is formed in the constructed wetland, the electron transfer process in the system is promoted, and the degradation of organic pollutants is accelerated. At the same time, a large number of adsorption sites exist on the surface of the sludge biochar, and the strong adsorption of iron oxide can effectively remove antibiotics and various pollutants in water. The pollutant concentration can be greatly reduced, and the water quality purification effect can be improved. The sulfonamide antibiotics and conventional pollutants in water can be effectively removed.

[0021] (3) The present application is provided with a water collecting pipe at the bottom of each filler layer for controlling the drainage of the system, the first water collecting pipe is used for controlling the water level in the system, the second water collecting pipe is used for collecting water for analysis, and the third water collecting pipe is used for emptying the reoxygenation. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 The present application is a sludge bio-constructed wetland flow chart.

[0023] Figure 2 The present application is a sludge bio-constructed wetland structure schematic diagram.

[0024] Figure 3 The present application is a sludge bio-constructed wetland structure schematic diagram.

[0025] Markings of components in the drawings:

[0026] 1-peristaltic pump, 2-inlet pipe, 3-distribution pipe, 4-horn, 5-first water collecting pipe, 6-valve, 7-wetland plant, 8-vermiculite filler layer, 9-sludge biochar composite filler layer, 10-ceramic filler layer, 11-second water collecting pipe, 12-third water collecting pipe, 13-housing, 14-filler module, 15-water supply module. DETAILED DESCRIPTION

[0027] The application purposes of the present application will be described in further detail in combination with the drawings and specific embodiments. The embodiments cannot be described one by one here, but the implementation manners of the present application are not limited to the following embodiments.

[0028] Embodiment one

[0029] A vertical flow constructed wetland system, comprising a housing 13, a filler module 14 and a water supply module 15; the filler module 14 comprises a vermiculite filler layer 8, a sludge biochar composite filler layer 9 and a ceramic filler layer 10; the water supply module 15 comprises a peristaltic pump 1, an inlet pipe 2, a distribution pipe 3 and a water collecting pipe, the water collecting pipe comprises a first water collecting pipe 5, a second water collecting pipe 11 and a third water collecting pipe 12; each water collecting pipe comprises a horn 4, a first water collecting pipe 5 and a valve 6.

[0030] The peristaltic pump 1 is arranged outside the housing 13, the inlet end of the inlet pipe 2 draws sewage from an external sewage pool through the peristaltic pump 1, the outlet end of the inlet pipe 2 is connected with the inlet end of the annular distribution pipe 3 through the top of the housing 13, the distribution pipe 3 is made of silica gel hose, a plurality of openings are arranged at fixed intervals on the pipe body towards the vermiculite filler layer 8, and the distribution pipe 3 is arranged above the vermiculite filler layer 8. The silica gel material ensures the flexibility and corrosion resistance of the distribution pipe 3, and the sewage is uniformly infiltrated to the lower filler through the annular distribution pipe 3;

[0031] The housing 13 is internally provided with, from top to bottom, a 30cm-thick vermiculite filler layer 8, a 30cm-thick sludge biochar composite filler layer 9 and a 30cm-thick ceramic filler layer 10, the vermiculite filler layer 8 is planted with acorus calamus, the planting density is 90 plants per square meter, and the particle size of the vermiculite is 5-10mm. The vermiculite filler layer 8 is arranged to filter suspended solids SS in the sewage, facilitate uniform water distribution, prevent uneven distribution of the sewage in the system, and support the growth of aquatic plants. The aquatic plants have strong pollution resistance, high survival rate, and the characteristics of absorbing pollutants by planting aquatic plants.

[0032] The first water collecting pipe 5 is arranged between the vermiculite filler layer 8 and the sludge biochar composite filler layer 9, the bell mouth 4 of the first water collecting pipe 5 is opened towards the vermiculite filler layer 8, and is used for controlling the water level in the system; the bell mouth 4 is connected with a PVC pipe through a 90° elbow pipe, the PVC pipe extends to the outside of the shell 13 through a water outlet hole formed on the right side of the shell 13, and the manual butterfly valve 6 is installed on the PVC pipe outside the shell 13 and is used for controlling the water flow switch.

[0033] The sludge biochar composite filler layer 9 is located between the vermiculite filler layer 8 and the ceramsite filler layer 10, and is a uniform mixture of sludge biochar, ceramsite and river sand at a volume ratio of 1:1:1, wherein the particle size of the sludge biochar is 4-6 mm, the particle size of the ceramsite is 4-6 mm, and the particle size of the river sand is 1-2 mm; the mass ratio of iron powder, sludge and kaolin in the sludge biochar is 6:2:5, and the sludge biochar is prepared by drying the sludge, iron powder and kaolin into a ceramic blank and then sintering twice; the first carbonization temperature is 400 DEG C, the holding time is 50 min, and the second sintering condition is 900 DEG C, and the sintering time is 5 min. By combining the traditional substrate filler with the self-made sludge biochar substrate, the performance of the iron-carbon material in the sludge biochar is utilized to form a micro-current environment in the constructed wetland, promote the electron transfer process in the system, and accelerate the degradation of organic pollutants. At the same time, the large number of adsorption sites on the surface of the sludge biochar and the strong adsorption of iron oxides can effectively remove sulfonamide antibiotics and various pollutants in water. Therefore, the system can not only remove conventional pollutants, but also effectively deal with the challenge of special pollutants.

[0034] The sludge biochar composite filler layer 9 and the ceramsite filler layer 10 are provided with a second water collecting pipe 11, the bell mouth 4 of the second water collecting pipe 11 is opened towards the sludge biochar composite filler layer 9, and is used for water collection analysis, and the rest is the same as the first water collecting pipe 5.

[0035] The particle size of the ceramsite in the ceramsite filler layer 10 is 10-20 mm; the ceramsite filler layer 10 is arranged to increase the water permeability and air permeability of the system, which helps to prevent the occurrence of water accumulation and anaerobic environment in the wetland system, reduces the risk of blockage, prolongs the service life of the constructed wetland, and improves the stability of the system.

[0036] The third water collecting pipe 12 is installed between the ceramsite filler layer 10 and the inner bottom of the shell 13, the bell mouth 4 is opened towards the ceramsite filler layer 10, and is used for emptying oxygen, and the rest is the same as the first water collecting pipe 5.

[0037] The use method is as follows:

[0038] The user starts the peristaltic pump, and sewage is pumped into the water distribution pipe. The sewage flows into the filler through the hole below the water distribution pipe 3, first passes through the vermiculite filler layer 8 to filter suspended solids SS in the sewage, which is beneficial to uniform water distribution and prevents uneven distribution of sewage in the system. The aquatic plants 7 planted in the vermiculite filler layer 8 absorb part of the pollutants. When the water level in the system exceeds the preset height, the valve 6 of the first water collector pipe 5 can be opened to control the water level in the system. The treated sewage flows to the sludge biochar composite filler layer 9. The iron-carbon material in the sludge biochar forms a micro-current environment in the constructed wetland, promotes the internal electron transfer process of the system, and accelerates the degradation of organic pollutants. At the same time, by using a large number of adsorption sites on the surface of the sludge biochar and the strong adsorption of iron oxides, sulfonamide antibiotics and various pollutants in the water can be effectively removed. When the user needs to analyze the sewage, the valve 6 of the second water collector pipe 11 can be opened. The sewage treated by the sludge biochar composite filler layer 9 flows to the lower ceramsite filler layer 10. When it is necessary to empty the reoxygenation, the valve 6 of the third water collector pipe 12 is opened.

[0039] The above specific embodiments are preferred embodiments of the present application, and cannot limit the present application. Any changes or other equivalent replacement methods without departing from the technical scheme of the present application are included in the protection scope of the present application.

Claims

1. A high dissolved oxygen content constructed wetland system for the removal of sulfonamide antibiotics, characterized in that, The application relates to a sewage treatment device, which comprises a shell (13), a filler module (14) and a water supply module (15); the filler module (14) is installed in the shell (13), the shell (13) is provided with a water outlet, the filler module (14) comprises, from top to bottom, a vermiculite filler layer (8), a sludge-biochar composite filler layer (9) and a ceramsite filler layer (10), the thicknesses of the vermiculite filler layer (8), the sludge-biochar composite filler layer (9) and the ceramsite filler layer (10) are respectively 20-40 cm, wetland plants (7) are planted in the vermiculite filler layer (8), and the sludge-biochar composite filler layer (9) is a filler layer formed by uniformly mixing sludge biochar, river sand and ceramsite in equal volumes. The water supply module (15) comprises a peristaltic pump (1), an inlet pipe (2), a distribution pipe (3) and a water collecting pipe, the inlet pipe (2) is connected with the peristaltic pump (1), one end of the distribution pipe (3) is connected with the inlet pipe (2), and the other end of the distribution pipe (3) is connected with the vermiculite filler layer (8); the water collecting pipe comprises a first water collecting pipe (5), a second water collecting pipe (11) and a third water collecting pipe (12), the first water collecting pipe (5) is installed between the vermiculite filler layer (8) and the sludge-biochar composite filler layer (9), the second water collecting pipe (11) is installed between the sludge-biochar composite filler layer (9) and the ceramsite filler layer (10), and the third water collecting pipe (12) is installed between the ceramsite filler layer (10) and the shell (13). The mass ratio of iron powder, sludge and kaolin in the sludge biochar is 1-6:2:

5.

2. The high dissolved oxygen content constructed wetland system for removing sulfonamide antibiotics according to claim 1, characterized in that, The first water collecting pipe (5), the second water collecting pipe (11) and the third water collecting pipe (12) respectively comprise a horn mouth (4), a 90-degree elbow pipe and a PVC pipe, the water inlet end of the PVC pipe is connected with the horn mouth (4) through the 90-degree elbow pipe, and the horn mouth (4) is upwardly open; the water outlet end of the PVC pipe penetrates through the water outlet of the shell (13) and extends to the outside of the shell (13).

3. The high dissolved oxygen content constructed wetland system for removing sulfonamide antibiotics according to claim 2, characterized in that, The PVC pipe is provided with a valve (6), and the valve (6) is located outside the shell (13).

4. The high dissolved oxygen content constructed wetland system for removing sulfonamide antibiotics according to claim 1, characterized in that, The particle size of the sludge biochar is 4-6 mm, the particle size of the river sand is 1-2 mm, and the particle size of the ceramsite is 4-6 mm.

5. The high dissolved oxygen content constructed wetland system for removing sulfonamide antibiotics according to claim 1, characterized in that, The particle size of the ceramsite in the ceramsite filler layer (10) is 10-20 mm.

6. The high dissolved oxygen content constructed wetland system for removing sulfonamide antibiotics according to claim 1, characterized in that, The wetland plants (7) comprise one or more of aloe, reed, cattail and rush.

7. The high dissolved oxygen content constructed wetland system for removing sulfonamide antibiotics according to claim 1, characterized in that, The particle size of the vermiculite in the vermiculite filler layer (8) is 5-10 mm.

8. The high dissolved oxygen content constructed wetland system for removing sulfonamide antibiotics according to claim 1, characterized in that, The distribution pipe (3) is made of a silica gel hose and has the shape of a ring, and the pipe body is provided with a plurality of holes.

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