CN201372233Y - Unpowered Integrated Constructed Wetland Sewage Treatment System - Google Patents

Abstract

The utility model discloses an unpowered integrated artificial wetland sewage treatment system. It is characterized in that the vertical flow sewage ecological purification tank is divided into upper and lower partitions. The pre-treated domestic sewage is lifted by the pump or enters the water distribution system relying on the natural liquid level difference. The pretreated sewage is evenly distributed in the water distribution system through the cross water distribution network On the nitrification area of the vertical submerged ecological purification tank, it infiltrates vertically into the artificial matrix layer of the nitrification area and the denitrification area in turn. The water distribution system implements intermittent water distribution for the ecological purification tank, and a non-powered air distribution system is installed at the bottom and inside of the upper nitrification area. The system realizes continuous reoxygenation of the nitrification area, the water from the upper nitrification area directly enters the lower denitrification area, and the lower denitrification area is equipped with a water collection and discharge system. The water collection port is located below the denitrification area, and the water outlet is located above the denitrification area. , so that the effluent maintains a certain water level in the denitrification area. The utility model can realize unpowered natural reoxygenation of the wetland, occupies a small area, and integrates nitrification and denitrification with high-efficiency denitrification.

Description

Unpowered Integrated Constructed Wetland Sewage Treatment System

technical field

The utility model relates to the technical field of environmental protection, in particular to ecological engineering technology for sewage treatment.

Background technique

Constructed wetland sewage treatment technology is a new ecological engineering technology for sewage treatment that emerged in the 1970s. It has the advantages of low investment, low energy consumption, convenient management, and no secondary pollution. It is gradually being used in rural areas and small and medium-sized cities and towns. Sewage treatment field.

Constructed wetlands are artificially constructed, controllable and engineered wetland systems, generally composed of pools, artificial filler substrates, water distribution systems, water collection systems and plants growing on artificial substrates. It is a unique substrate-plant - Microbial ecosystems. The basic principle of water quality purification in the constructed wetland ecosystem is: plant specific plants on certain fillers, add sewage to the artificially constructed wetland similar to a swamp, and when the sewage flows through the constructed wetland, it is filtered through sand, gravel and soil , A variety of microbial activities in the plant rhizosphere make the water quality purified. According to experiments and a large number of engineering practices, artificial ecological filter beds can remove BOD, TSS, N, and P well, and are also very effective in removing pathogenic bacteria, refractory organic compounds, and metal ions. The comprehensive effects of constructed wetlands on the environment and economy are mainly reflected in the following aspects: making up for or reducing the impact of agricultural and urban development on natural wetlands; building aquatic systems to produce food and fiber; regulating stormwater runoff and flood control; treatment to improve water quality.

The submerged vertical flow constructed wetland is a type of constructed wetland. The main features are: the water distribution system is laid flat in the upper matrix, and the sewage is evenly distributed on the horizontal section of the matrix. The sewage flows downward evenly, and the sewage is obtained during the flow process. Purification: A water collection system is laid in the bottom matrix of the wetland, and the effluent that is evenly distributed in the horizontal section after collection and treatment is collected and discharged. Submerged vertical flow constructed wetlands make full use of the wetland space and give full play to the synergy between systems. After sewage treatment, most of the organic matter can be removed and nitrification can be carried out more fully. It has gradually become the mainstream direction of the development of constructed wetland technology. However, the traditional submerged vertical flow constructed wetland has a poor denitrification effect on sewage, and cannot achieve the purpose of efficient nitrogen and phosphorus removal. Due to insufficient reoxygenation during the treatment process, the effect of aerobic deorganization on sewage is not very good. ideal. In view of the above defects, researchers have invented a large number of technologies to improve subsurface vertical flow constructed wetlands to increase the efficiency of pollutant treatment. For example, the Chinese patent CN 1263688C "Method for Removing Nitrogen and Phosphorus by Vertical Flow-Horizontal Flow Composite Constructed Wetland of Domestic Sewage" discloses a tandem composite constructed wetland treatment process in which the vertical flow constructed wetland is in front and the horizontal flow constructed wetland is followed. Artificially supplementing untreated sewage as a carbon source in front of the horizontal flow wetland increases the denitrification effect of the horizontal flow constructed wetland. However, the vertical flow wetland cannot fully reoxygenate, which affects the treatment effect of nitrification and aerobic oxidation. The connection of two wetlands occupies a large area, high cost, and poor practicability. Chinese patent CN 1325397C "Sequence Batch Submerged Flow Constructed Wetland Sewage Treatment Process" discloses a method of using mechanical automation to control solenoid valves to intermittently drain water from wetlands to achieve staged reoxygenation. It increases the reoxygenation effect of the vertical underflow constructed wetland to a certain extent, but it requires an additional power control system, which increases investment, and has no significant promotion effect on denitrification and denitrification of sewage.

Contents of the invention

The utility model aims to provide a non-powered integrated constructed wetland sewage treatment system capable of realizing unpowered natural reoxygenation of wetlands, occupying a small area, and integrating nitrification and denitrification with high-efficiency nitrogen removal.

The technical scheme adopted by the utility model to solve the above-mentioned technical problems is: a non-powered integrated artificial wetland sewage treatment system, including a vertical flow sewage ecological purification tank composed of two parts, a nitrification area and a denitrification area, and a substrate in the filling tank , sewage pretreatment system, water distribution system, water collection system, air distribution system, sewage system and plants growing on the substrate, characterized in that:

The vertically flowing sewage ecological purification tank is divided into upper and lower areas: a nitrification area and a denitrification area, the nitrification area is on the top, and the denitrification area is on the bottom, and the artificial matrix is filled in the nitrification area and the denitrification area respectively;

The sewage pretreatment system uses one or several pretreatment processes in the grid, three-format sedimentation tank, and anaerobic tank to pretreat sewage with different pollution loads, and the pretreated domestic sewage is lifted by a water pump or Rely on the natural liquid level height difference to enter the water distribution system; the pretreated sewage is evenly distributed on the nitrification area of the vertical submerged ecological purification tank through the cross water distribution pipe network, and then vertically penetrates into the artificial matrix layer of the nitrification area and denitrification area; water distribution The system implements intermittent water distribution for the ecological purification tank, and a non-powered air distribution system is installed at the bottom and inside of the upper nitrification area to realize continuous reoxygenation of the nitrification area, so that the sewage can perform efficient aerobic and nitrification in the upper nitrification area The effluent from the upper nitrification area directly enters the lower denitrification area, where facultative oxygenation and denitrification are carried out; the lower denitrification area is equipped with a water collection and discharge system, the water collection port is located below the denitrification area, and the water outlet is located at Above the denitrification area, keep the effluent at a certain level in the denitrification area.

In the vertical flow sewage ecological purification tank, the sewage realizes physical purification and biological purification through the interaction with the substrate, microorganisms and plant roots, and achieves the purpose of reducing SS, BOD, COD, bacteria and efficient nitrogen and phosphorus removal of sewage.

Preferably, the water distribution system is a water distribution pipe network arranged 5-10 cm below the substrate surface in the upper sewage nitrification area, and the water distribution pipe network includes a water inlet valve, a water inlet, a water distribution main pipe and a plurality of water distribution main pipes The connected water distribution branch, the water distribution main pipe and the water distribution branch are distributed vertically or cross the word "Wang", and there are small water distribution holes on the water distribution branch.

Preferably, the water collection system is a water collection pipe network arranged in the lower denitrification area, and the water collection pipe network includes a water collection port, a vertical water collection branch, a horizontal water collection branch, and a connection with the vertical water collection branch and the horizontal water collection branch The main water collecting main, water outlet and water outlet valve; the main water collecting main and the horizontal water collecting branches are distributed in the shape of vertical "king" or cross "king", and the vertical water collecting branch and the horizontal water collecting branch and the water collecting main are in the form of The space is vertically distributed, and the middle pipes are connected; the water collection port is set at the end of the vertical water collection branch, which is composed of several small water collection holes on the circular pipe section, and the distance between the water collection port and the bottom of the entire pool is not greater than the denitrification 1/3 of the total height of the area; the horizontal water collection branch, the water collection main pipe and the water collection outlet are located at the same level, and their horizontal position is between the top of the lower denitrification tank and the height between 2/3 of the top of the denitrification tank.

As a preference, the air distribution system is distributed on the upper layer with one or more sets of air distribution pipe networks filled with small holes; each group of air distribution pipe network consists of horizontal air distribution pipes and several vertical air distribution pipes vertically connected Composed of branches; one end of the vertical air distribution branch is connected to the horizontal air distribution branch between the bottom of the upper nitrification area and 2/3 of the height from the bottom of the upper nitrification area, and the other end vertically protrudes from the top of the pool body matrix to communicate with the outside air , the top of the vertical air distribution branch is 3-10cm higher than the surface of the matrix layer, and a dust cap is provided to prevent large particles from entering the pipe body and blocking the air distribution pipe.

As a preference, the bottom of the denitrification area of the vertically flowing sewage ecological purification tank can be concave in the middle, the lowest part of the depression is provided with a drainage pipe, the surface of the drainage pipe is covered with small drainage holes, one end of the drainage pipe is closed, and the other end protrudes out of the groove The outside is used as the sewage outlet, and the sewage outlet is equipped with a sewage valve. During normal operation, the sewage valve is closed, and the sewage valve is opened when the tank is flushed.

As a preference, the structure layering and material thickness of the artificial matrix from bottom to top in the upper nitrification area are as follows: the drainage layer adopts gravel with a particle size of 8-16mm and a thickness of 10-35cm; the transition layer adopts gravel with a particle size of 4-8mm and a thickness of 10-35cm. 8-15cm; biochemical treatment transition layer, using special graded 0.2-6mm mud-free coarse sand, thickness 50-60cm; surface layer adopts gravel with particle size 8-16mm, thickness 4-8cm; the upper part of the vertical flow sewage ecological purification tank is planted The plants are selected from one or more of reeds, reed bamboos, cattails, cannas, windmill grass, zaili grass, vetiver, roses, roses, marigolds, etc.;

The structural layering and material thickness of the inner matrix of the lower denitrification area from bottom to top are as follows: anti-seepage layer, using PE film double-sided geotextile with a thickness of 0.5mm or more or natural clay anti-seepage layer with a thickness of 1-5cm; transition layer , using gravel with a particle size of 5-10mm and a thickness of 10-20cm; the biochemical treatment transition layer uses a cinder matrix layer of 0.2-6mm and a thickness of 50-60cm.

As a preference, the sidewalls around the upper nitrification zone may present a certain slope, with a slope range of 0-10%; the sidewalls around the lower denitrification zone may present a certain slope, with a slope range of 0-5%.

The utility model has the following beneficial effects:

Nitrification and denitrification are integrated, phosphorus removal and filter residue are used, and nitrogen and phosphorus are removed efficiently; the structure is simple, the floor area is small, and land resources are saved. Restrictions; intermittent water inflow, aerobic upper layer and aerobic lower layer are ingeniously designed to realize natural unpowered reoxygenation to promote oxidation, nitrification and other reactions, and improve the efficiency of aerobic treatment of pollutants; plant wetland plants such as reeds and reeds, and resist Acid-base, can remove pollutants with heavy pollution load.

The artificial wetland sewage treatment system involved in the utility model has the advantages of simple structure, easy installation, uniform water distribution, free and convenient water level adjustment, no power consumption, and low cost, and can be used for various types of sewage treatment, such as domestic sewage, garbage leachate, Agricultural sewage, petrochemical wastewater, urban rainstorm surface runoff and pollution control of lakes and rivers, etc. Choosing the right plant species can also beautify the surrounding environment.

Description of drawings

Fig. 1 is a kind of embodiment structural representation of the utility model;

Fig. 2 is a kind of structural representation of Fig. 1 water distribution pipeline network;

Fig. 3 is another schematic diagram of the structure of the water distribution pipe network in Fig. 1;

Fig. 4 is the top view of the structure of the drainage network in Fig. 1;

Fig. 5 is a sectional view of the water distribution branch.

In the figure: 1-pretreatment tank, 2-water pump, 3-water inlet valve, 4, wetland plants, 5-water distribution pipe network, 6-pool body nitrification area, 7-dust cap, 8-vertical gas distribution branch, 9-Horizontal air distribution pipe, 10-Air distribution small hole, 11-Water outlet valve, 12-Water outlet, 13-Vertical water collection branch, 14-Sewage outlet, 15-Drainage valve, 16-Drainage hole, 17-Drainage pipe , 18-Water collection port, 19-Pond denitrification area, 20-Water inlet, 21-Water distribution supervisor, 22-Water distribution branch, 23-Water distribution small hole, 24-Horizontal water collection branch, 25-Water collection supervisor

Detailed ways

The technical solution of the present utility model is further specifically described below through implementation examples and in conjunction with the accompanying drawings.

In this example, pretreatment is usually done in a three-format sedimentation tank, and the sludge will be cleaned periodically. For sewage with higher concentration, an anaerobic pool can be built at the front end of the filter bed. Good pre-sedimentation treatment is the guarantee for the long-term effective operation of the artificial ecological filter bed, and it can also play a role in regulating the amount and quality of sewage water. The pretreated sewage is lifted by the intermittent sewage pump and evenly distributed to the surface of the artificial substrate in the upper nitrification area of the vertical flow sewage ecological purification tank according to the set control parameters.

The main sewage treatment area of the utility model - the vertical flow sewage ecological purification tank is divided into two connected upper and lower areas. The side walls around the upper nitrification area have a slope of 5%, and the lower bottom is connected to the upper part of the lower denitrification area. , the lower denitrification area is a cuboid pool body; the upper nitrification area pool is filled with artificial substrate as a sewage filter bed and microbial aerobic oxidation and nitrification bed, and the artificial substrate filled in the lower denitrification area is used as a sewage filter bed and microbial facultative oxidation and denitrification bed. The matrix filled in the upper nitrification area from bottom to top is: gravel layer with a thickness of 10-35cm and a particle size of 8-16mm; a gravel layer with a thickness of 8-15cm and a particle size of 4-8mm; a thickness of 50-60cm and a particle size of 0.2 -6mm mud-free coarse sand layer; thickness 4-8cm, particle size 8-16mm gravel surface. The wetland plants planted on the surface of the ecological purification bed are reeds and reed bamboos.

The pretreated sewage is lifted by the water pump 2, enters the water distribution main pipe 21 and the water distribution branch 22 of the cross water distribution pipe network 5 through the water inlet valve 3, and finally enters the pool body matrix layer through the water distribution small hole 23 on the water distribution branch 22. The water distribution branch 22 is on the same level as the water distribution main pipe 21, and is vertically connected to it in the shape of a "king" (as shown in Figure 2) or crossed in the shape of a "king" (as shown in Figure 3), and the end of the water distribution branch 22 Closed, the pipe body is evenly opened with water distribution small holes 23 every 10-20cm, and the water distribution small holes are left and right symmetrical, and are all located below the horizontal center line of the pipe body.

The unpowered gas distribution system consists of 3-5 groups of gas distribution pipe networks, which are evenly buried inside the upper nitrification tank. Each group of air distribution pipe network is composed of connected horizontal air distribution branches and vertical air distribution branches 8. Among them, the vertical air distribution branches close to the outer wall of the pool can be properly inclined along the slope of the pool body, and there are countless air distribution holes on the pipe body. The hole 10, wherein the upper end of the vertical air distribution branch 8 extends out of the pool body is covered with a dustproof cap. This unpowered air distribution system can make the pool matrix naturally rich in oxygen and fully uniform in oxygen, which meets the needs of microbial nutrient reactions. In addition, the sewage flowing from the upper nitrification area into the lower denitrification area can also distribute air without power during the flow process. Under the action of the system, dissolved oxygen is increased to form a facultative oxygen environment in the lower sewage treatment area and improve the oxidation efficiency of sewage.

The sewage treated in the upper nitrification area directly infiltrates into the lower denitrification treatment area. The matrix filled in this area is gravel with a thickness of 10-20cm and a particle size of 5-10mm from bottom to top; a thickness of 50-60cm and a particle size of 0.2 -6mm cinder matrix layer. The pool body is laid with a submerged water collection pipe network, which has the following characteristics: the space between the vertical water collection branch 13 and the horizontal water collection branch 24 and the water collection main pipe 25 is vertically distributed, and the middle pipes are connected; the water collection port is located in the vertical water collection The end of the branch 13 is composed of several small water collection holes on the circular pipeline section. The distance between the water collection port and the bottom of the entire pool body is not greater than 1/3 of the total height of the denitrification area; the horizontal water collection branch 24, the collection The water main pipe 25 and the water collecting port are located at the same level, and their horizontal positions are between the top of the lower denitrification tank body and the height between 2/3 of the top of the denitrification tank body. The sewage from the upper nitrification area enters the lower denitrification area and continues to infiltrate vertically until it reaches the bottom of the denitrification area. Since the outlet of the water collection pipe network is located at the upper part of the denitrification tank, the water that is treated in the denitrification area to the bottom of the pool is in the pool body. The bottom enters the water collection port, but the water cannot be discharged immediately. The sewage accumulates upwards at the bottom, and the water can only be discharged from the water outlet after the water outlet level of the vertical water collection branch reaches the height of the water outlet. The role of the submerged water collection pipe network is to increase the residence time of sewage in the lower denitrification bed, create a facultative oxygen environment, and make the degradation of organic matter and total nitrogen more sufficient.

As shown in Figure 1, the bottom of the present embodiment is provided with a sewage pipe, and the pipe body of the sewage pipe has a large number of small sewage holes, which are connected to the outside world through the sewage outlet 14, and a sewage valve 15 is provided in front of the sewage outlet. When the constructed wetland sewage treatment system is in normal operation, the sewage valve is closed. When the matrix layer of the filter bed is clogged or needs to be cleaned, the sewage valve is opened to flush water from the filter pool to the upper water distribution pipe network, and the flushed sewage is discharged out of the filter pool through the sewage pipe to achieve the purpose of system maintenance.

Claims (10)

1. A non-powered integrated artificial wetland sewage treatment system, including a vertical flow sewage ecological purification tank composed of two parts: a nitrification area and a denitrification area, an artificial substrate in the filling tank, a sewage pretreatment system, a water distribution system, a collecting Water system, gas distribution system, sewage system and plants growing on artificial substrates, characterized in that: the vertical flow sewage ecological purification tank is divided into upper and lower divisions: nitrification area and denitrification area; the nitrification area is on the top, The denitrification area is below, and the artificial matrix is filled in the nitrification area and the denitrification area respectively; the sewage pretreatment system uses grilles, three-format sedimentation tanks, and anaerobic tanks for pretreatment, and then is lifted by water pumps or relies on The natural liquid level height difference enters the water distribution system; the water distribution pipe network is evenly distributed in the upper nitrification area, and the bottom and inside of the nitrification area are equipped with an unpowered gas distribution system; Below the denitrification area, the water outlet is located above the denitrification area. 2. The non-powered integrated artificial wetland sewage treatment technology according to claim 1, characterized in that: the water distribution system is a water distribution pipe network arranged 5-10 cm below the surface layer of the substrate in the nitrification area of the upper sewage, and the water distribution pipe network In turn, it includes a water inlet valve, a water inlet, a water distribution main pipe and multiple water distribution branches connected to the water distribution main pipe; There are small holes for water distribution on the branches. 3. The unpowered integrated constructed wetland sewage treatment technology according to claim 1, characterized in that: the water collection system is a water collection pipe network arranged in the lower denitrification area; the water collection pipe network sequentially includes a water collection outlet, The vertical water collection branch, the horizontal water collection branch, the water collection main pipe connected with the vertical water collection branch and the horizontal water collection branch, the water outlet and the water outlet valve; "Wang" character distribution; the vertical water collection branch and the horizontal water collection branch and the water collection main pipe are vertically distributed in space, and the middle pipeline is connected; the horizontal water collection branch, the water collection main pipe and the water collection mouth are located at the same level, and their horizontal positions The top of the lower denitrification tank is between 2/3 of the height from the top of the denitrification tank. 4. The non-powered integrated constructed wetland sewage treatment technology according to claim 3, characterized in that: the water collection outlet is set at the end of the vertical water collection branch, and is a plurality of small water collection holes on the circular pipeline section. The distance between the water collection port and the bottom of the entire pool body is not greater than 1/3 of the total height of the denitrification area. 5. The non-powered integrated constructed wetland sewage treatment technology according to claim 1, 2 or 3, characterized in that: the air distribution system is distributed in the upper layer with one or more sets of air distribution pipes covered with small holes Each group of air distribution pipe network is composed of horizontal air distribution pipes and several vertical air distribution branches vertically connected to the horizontal air distribution pipes; one end of the vertical air distribution branches is connected from the bottom of the upper nitrification area to the height of 2/3 from the bottom of the upper nitrification area Between the horizontal air distribution branches, the other end vertically protrudes from the top of the substrate of the pool body and communicates with the outside air. The top of the vertical air distribution branch is 3-10cm higher than the surface of the substrate layer, and is equipped with a dustproof cap. 6. The non-powered integrated constructed wetland sewage treatment technology according to claim 1, 2 or 3, characterized in that: the bottom of the denitrification area of the vertical flow sewage ecological purification tank is concave in the middle, and the lowest part of the depression is set There is a drainage pipe, and the surface of the drainage pipe is provided with a plurality of drainage holes. One end of the drainage pipe is closed, and the other end protrudes out of the groove as a sewage outlet, and the sewage outlet is provided with a sewage discharge valve. 7. The non-powered integrated constructed wetland sewage treatment technology according to claim 1, 2 or 3, characterized in that: the structural layering and material thickness of the artificial substrate inside the upper nitrification area from bottom to top are as follows: drainage layer , use gravel with a particle size of 8-16mm and a thickness of 10-35cm; the transition layer uses gravel with a particle size of 4-8mm and a thickness of 8-15cm; the transition layer for biochemical treatment uses a special gradation of 0.2-6mm mud-free coarse sand with a thickness of 50- 60cm; for the surface layer, use gravel with a particle size of 8-16mm and a thickness of 4-8cm. 8. The non-powered integrated constructed wetland sewage treatment technology according to claim 1, 2 or 3, characterized in that: the structure layering and material thickness of the artificial matrix inside the lower denitrification area from bottom to top are as follows: transition For the layer, use gravel with a particle size of 5-10mm and a thickness of 10-20cm; for the biochemical treatment transition layer, use a cinder matrix layer of 0.2-6mm and a thickness of 50-60cm. 9. The non-powered integrated constructed wetland sewage treatment technology according to claim 8, characterized in that: under the transition layer, there is a PE film double-sided geotextile with a thickness of more than 0.5mm or a natural geotextile with a thickness of 1-5cm. Clay anti-seepage layer. 10. The non-powered integrated constructed wetland sewage treatment technology according to claim 1, 2 or 3, characterized in that: the side walls around the upper nitrification area have a slope of 0-10%; the surroundings of the lower denitrification area The side walls have a slope of 0-5%.

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