A subsurface water ecological purification bed system suitable for high altitude and cold areas of plateaus

Abstract

The present invention discloses an ecological purification bed system for subsurface water in cold areas at high altitudes on the plateau, and belongs to the technical field of sewage treatment and environmental protection. In view of the problems that the existing rigid lining system is inconvenient to construct, difficult to green, destroys the hydrological cycle and ecological structure of natural rivers, and river regulation causes natural rivers to become channels, the present invention provides an ecological purification bed system for subsurface water in cold areas at high altitudes on the plateau that can operate stably in a low-temperature environment on the plateau. The purification bed of the present invention utilizes the hydraulic flow state of the downward subsurface wetland to fully contact the incoming water with the composite filler, and utilizes the adsorption function of each layer of filler in the purification bed and the synergistic effect of plants and microorganisms to purify N, P and heavy metals in the water. The high specific surface area of ​​the composite filler used in the purification bed can provide a high-load microbial carrier, enhance the self-purification ability of the water body, and enable the purification bed to have the advantages of microbial degradation, carrier adsorption, plant absorption, and environmental beautification.

Description

Technical Field

[0001] The invention relates to a subsurface water ecological purification bed system suitable for plateau high-altitude cold areas, and belongs to the technical field of sewage treatment and environmental protection. Background Art

[0002] The rigid lining system of the traditional purification bed has a high overall cost, is not easy to plant grass and green, and cannot meet ecological requirements; it has poor durability and poor adaptability to small-scale deformation of the channel, is prone to local damage and structural instability. Once local damage occurs, it is easy to cause large-scale damage, which is difficult to repair and inconvenient to construct.

[0003] While existing technologies for river ecological management have been extensively researched and explored, they are primarily focused on water pollution in the southwest. River ecological management in the high-altitude, cold regions of the northwest is still rare. Existing river ecological management solutions are unstable in the low-temperature plateau environment. Therefore, it is crucial to develop a subsurface water ecological purification bed system for high-altitude, cold plateau regions that can operate stably in these environments while effectively reducing pollutant levels in river water. Summary of the Invention

[0004] One of the purposes of the present invention is to provide a subsurface water ecological purification bed system that can stably operate in a low-temperature environment of a plateau and a cold area at a high altitude.

[0005] Another purpose of the present invention is to solve the problems of inconvenient construction and greening of the rigid lining system, destruction of the hydrological cycle and ecological structure of the natural river, and channelization of the natural river caused by river regulation.

[0006] The technical solution of the present invention:

[0007] A subsurface water culvert ecological purification bed system suitable for high-altitude and cold plateau areas, comprising a plurality of subsurface water culvert ecological purification beds, each of which is surrounded by a reinforced concrete pool wall 3, and an overflow weir 2 is provided between adjacent subsurface water culvert ecological purification beds;

[0008] The subsurface water ecological purification bed is composed of backfilled scattered rocks 13, pebble layer 12, crushed stone layer 11, first composite filler layer 10, second composite filler layer 9, surface planting soil 8 and matrix prefabricated blocks 4 from bottom to top;

[0009] The matrix prefabricated block 4 is a concrete structure with a quadrilateral nest hole in the middle. Adjacent matrix prefabricated blocks 4 are connected to each other by galvanized steel cables 6 to form a chain matrix. The quadrilateral nest holes of the matrix prefabricated blocks 4 are filled with gravel, and plants 7 are planted in the gaps of the chain matrix.

[0010] It is further defined that the particle size D of the backfill loose rock 13 is not less than 300 mm; the particle size of the pebble layer 12 is 15-18 mm and the thickness is 150 mm; the particle size of the crushed stone layer 11 is 6-15 mm and the thickness is 150 mm; the particle size of the first composite filler layer 10 is 3-15 mm and the thickness is 200 mm; the particle size of the second composite filler layer 9 is 0.5-2 mm and the thickness is 230 mm; the thickness of the surface planting soil 8 is 200 mm; and the thickness of the matrix prefabricated block 4 is 120 mm.

[0011] It is further defined that the roots of the plants 7 planted in the surface planting soil 8 are introduced with domesticated active microorganisms and activated carbon as an active microorganism carrier.

[0012] It is further defined that the active microorganisms are aerobic microorganisms, anaerobic microorganisms and / or facultative microorganisms.

[0013] It is further specified that the microorganisms are cultured on a substrate and domesticated using river water so that the microorganisms adapt to the water quality characteristics of the river.

[0014] It is further specified that active microorganisms are introduced into the soil where plants grow using activated carbon as a carrier, and the amount of microorganisms (including the carrier) required for each subsurface water ecological purification bed is approximately 0.5g.

[0015] It is further defined that the first composite filler layer 10 and the second composite filler layer 9 are composed of composite fillers of different particle sizes, and the composite fillers include serpentine, steel slag and biological fillers.

[0016] It is further defined that the main components and contents (mass fraction) of serpentine are as follows: SiO2>30%, MgO>30%, Fe2O3>4% and Al2O3>2%.

[0017] It is further defined that the main components and contents (mass fraction) of steel slag are as follows: SiO2>10%, TFe>10%, CaO>35%, MgO>7%, P2O5>1%, Al2O3>5%.

[0018] It is further defined that the main components and contents (mass fraction) of the biological filler are as follows: SiO2 50% to 70%, Al2O3 14% to 20%, Fe2O3 5% to 10%, CaO and MgO 3% to 7%, K2O and Na2O 1.5% to 4%, and organic matter 1% to 2%.

[0019] It is further defined that each matrix prefabricated block 4 is provided with two steel cable connection holes, and the galvanized steel cables 6 pass through the steel cable connection holes to connect adjacent matrix prefabricated blocks 4 to each other to form a chain matrix, and the chain matrix is ​​fixed in the river channel by pre-buried steel cable rings 5.

[0020] The present invention has the following beneficial effects: It evenly distributes incoming water flowing through the purification bed on the surface of the purification bed. Simultaneously, the hydraulic flow pattern of the downstream subsurface wetland ensures that the incoming water fully contacts the composite filler. This utilizes the adsorption function of each layer of filler in the purification bed, as well as the synergistic effect of plants and microorganisms, to purify nitrogen, phosphorus, and heavy metals in the water. The high specific surface area of ​​the composite filler used in the purification bed of the present invention provides a high-load microbial carrier. This integrates principles from materials science, microbiology, and aquatic ecology to enhance the self-purification capacity of the water body, resulting in the purification bed combining the advantages of microbial degradation, carrier adsorption, plant absorption, and environmental beautification.

[0021] The present invention also has the following beneficial effects:

[0022] (1) The subsurface water ecological purification bed provided by the present invention is open-hole, providing a habitat for the construction, growth and development of microorganisms, and a more stable living environment for vegetation and small shrubs, giving full play to the self-purification functions of rivers, soil, and vegetation. The large-scale plant growth also serves as an ecological barrier to the riverbank, effectively alleviating pollution caused by non-point sources and surface runoff in the riverbank, while improving the diversity of the riverbank ecosystem. In addition, vegetation and small shrubs grow in the gaps of the chain matrix formed by the connection of the matrix prefabricated blocks, adsorbed on the bottom surface, and also increase the adsorption capacity of the matrix prefabricated blocks.

[0023] Furthermore, the interlocking matrix of prefabricated matrix blocks, with its open pores, allows river water to flow subsurface into the functional filler beneath the subsurface culvert's ecological purification bed. This functional filler, along with plants, plant roots, and microorganisms near these roots, forms a composite subsurface wetland. This composite subsurface wetland significantly enhances the subsurface culvert's ability to remove pollutants, significantly increasing the river's environmental capacity and enabling self-recovery of the river's ecological environment, thereby avoiding or further minimizing human impact on the existing river's operating model. Furthermore, even after ecological restoration, the river remains subject to the original basin's water resource planning. Even after the destruction of plants during both the wet and dry seasons, the river's ecological environment can still recover.

[0024] (2) The interlocking matrix formed by connecting the matrix prefabricated blocks of the present invention is a flexible connection structure of rigid blocks, which are interlocked as a whole. This structure not only fixes the internal filler of the bed, but also preserves or restores the original meandering or branched and scattered natural form of rivers and lakes. Moreover, this high-porosity, water-permeable flexible structure pavement also reduces the scouring force of river water when it enters the bed, can reduce the flow rate, reduce fluid pressure and improve drainage capacity, and provide a relatively stable environment for the growth of surface plants. In addition, the interlocking matrix is ​​interconnected by steel cables, which allows great flexibility between adjacent blocks, and the cross-section of the matrix prefabricated blocks is a two-sided bevel structure, so that the blocks can fit well together.

[0025] (3) The present invention selects cold-resistant aquatic plants such as yellow iris, water lily and cattail that are suitable for growing in high-altitude plateau areas, and carries out compound planting according to water quality characteristics and landscape adaptation requirements. At the same time, the chain matrix structure and composite filler filling method provide a relatively stable hotbed environment, ensuring the metabolic temperature requirements of microorganisms and plants in the functional areas of the filler bed. It has all-weather river water purification capabilities and is particularly suitable for high-altitude cold areas on the plateau.

[0026] (4) The composite filler used in the present invention is mainly made of serpentine, steel slag and biological filler, and is proportioned according to the requirements of water purification. The excellent permeability of the biological filler is fully utilized to improve the permeability of the bed, reduce the probability of blockage, and give full play to its adsorption performance for ammonia nitrogen, significantly reducing the content of organic pollutants, phosphorus, ammonia nitrogen and heavy metal ions in the water body. Under the joint action of plant roots, biofilm and composite filler, the continuity and efficiency of the pollutant adsorption, enrichment and conversion and utilization process are guaranteed. In addition, the composite filler can also effectively inhibit the formation of silt in rivers and lakes, cooperate with vegetation to absorb excess nutrients in the water body, and have a mutual restraining effect on phytoplankton (cyanobacteria, etc.) in the water, inhibiting the growth of phytoplankton. At the same time, the chemical activity of the active group of the composite filler is mainly manifested in the adsorption of heavy metal ions and anions (groups) and the adsorption and catalytic decomposition of organic matter. In neutral and slightly alkaline conditions, the active group is most active and can effectively adsorb metal elements such as copper, iron, lead, cadmium and nickel. Since this filler contains a large number of hydroxyl groups, hydrogen bonds, unsaturated silicon-oxygen bonds and magnesium bonds, it can absorb a large number of anions (groups). The hydroxyl groups on the surface of the filler can be replaced by halogens (F, C1, etc.) or oxygen-containing anions, forming coordinated octahedrons with magnesium, fixing fluoride ions and the like on the mineral in the form of ionic bonds; the hydrogen bond layer distributed on the surface of the filler is highly active, and this exposed hydrogen nucleus can absorb atoms and atomic groups with high electronegativity such as O, F, N, and C1; the unsaturated silicon-oxygen bonds can absorb anionic groups containing arsenic (H2AsO; VO 3- , H2Cr2O7 and MnO 4- The trace dissolution of OH- in the hydroxyl layer on the outer surface of the filler renders the water alkaline. Organic pollutants in water, such as trichlorfon, dibromophos, coumaphos, aminooxalyl, dalapon, fenthion, and nitrosamines, can be accelerated to decompose and hydrolyze under alkaline conditions, reducing their toxicity and even breaking down into non-toxic substances. Because this filler contains Mg+, it can form a precipitate with phosphates in wastewater. Furthermore, the composite filler, based on the concept of resource recycling, uses waste steel slag and serpentine ore scraps, which not only revolutionizes the development of ecological purification beds but also significantly promotes the development of a circular economy.

[0027] (5) The purification bed structure of the present invention is to directly backfill the bottom of the riverbed with scattered rocks, so that a water flow channel is left at the bottom of the riverbed, realizing the hydraulic automatic distribution of water from the bottom and surface; in the flood season, the matrix prefabricated blocks of the present invention have a nest hole and chamfer design. When the water flows through the surface of the purification bed, vortexes and high-speed water flows are formed, promoting the flushing and mud discharge of functional area sedimentation; in the dry season, river water enters the bed from the bottom through the water flow channel, disturbing the silt and preventing it from hardening, ensuring the connectivity of the system, and in special drought seasons, it can also utilize its own water retention function to operate.

[0028] (6) The present invention can also optimize the filler ratio for different pollution sources to purify sewage. For example, for sewage treatment plant tail water, such as this type of high-load point source pollutant discharge outlet, the technical process can increase the ratio of steel slag to serpentine to reduce the discharge of total phosphorus, heavy metals, etc. For non-point source pollution sources such as farmland drainage, the technical process can increase the ratio of ceramsite, increase the moisture content of the purification bed, and then use the plant roots to absorb organic pollutants in the sewage as their own nutrients, and the filler and plant roots can be used as carriers of biofilms, and then use the microorganisms on the biofilms to degrade pollutants in one step, ultimately reducing the content of pollutants entering the river. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is a cross-sectional view of the subsurface water ecological purification bed;

[0030] Figure 2 A schematic diagram of the structure of an interlocking matrix formed by connecting matrix prefabricated blocks;

[0031] Figure 3 This is a top view of the subsurface water ecological purification bed system;

[0032] Figure 4 Schematic diagram of the position of plants planted in the gaps of the interlocking matrix;

[0033] Figure 5 It is a structural diagram of the matrix prefabricated block;

[0034] Figure 6 This is a schematic diagram of the principle of automatic hydraulic distribution. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0036] The experimental methods used in the following examples are conventional methods unless otherwise specified. The materials, reagents, methods, and instruments used are conventional in the art and can be obtained commercially by those skilled in the art unless otherwise specified.

[0037] The present invention is achieved through the following technical solutions:

[0038] A subsurface water culvert ecological purification bed system suitable for high-altitude and cold plateau areas, the system comprises a plurality of subsurface water culvert ecological purification beds, each subsurface water culvert ecological purification bed is provided with a reinforced concrete pool wall 3 on its periphery, and an overflow weir 2 is provided between adjacent subsurface water culvert ecological purification beds;

[0039] The subsurface water ecological purification bed comprises, from bottom to top, scattered rocks 13, pebble layer 12, crushed stone layer 11, first composite filler layer 10, second composite filler layer 9, surface planting soil 8 and matrix prefabricated blocks 4;

[0040] The matrix prefabricated blocks 4 are concrete structures with a centrally located quadrilateral hole. Adjacent matrix prefabricated blocks 4 are interconnected by galvanized steel cables 6 to form an interlocking matrix. The quadrilateral holes in the matrix prefabricated blocks 4 are filled with gravel, and plants 7 are planted within the interlaced matrix. This arrangement creates a central hole in the subsurface water culvert's ecological purification bed, allowing river water to flow into the functional filler at its lower portion. Within the functional filler, river water then flows downstream, creating a composite subsurface flow wetland that integrates the functional filler, plants, plant roots, and microorganisms near the roots.

[0041] The particle size D of the loose rock 13 is no less than 300mm; the particle size of the pebble layer 12 is 15-18mm and the thickness is 150mm; the particle size of the crushed stone layer 11 is 6-15mm and the thickness is 150mm; the particle size of the first composite filler layer 10 is 3-15mm and the thickness is 200mm; the particle size of the second composite filler layer 9 is 0.5-2mm and the thickness is 230mm; the thickness of the surface planting soil 8 is 200mm; and the thickness of the matrix prefabricated blocks 4 is 120mm. This arrangement creates a layered structure within the subsurface water purification bed, forming a framework for the ecological purification bed and supporting the plants in the bed, providing an excellent anchoring and growth environment for plants and microorganisms. It also has a strong interception and adsorption effect on pollutants, including nitrogen, phosphorus, and heavy metals in the water. Furthermore, the loose rock backfill directly at the riverbed bottom creates a water flow channel, achieving automatic hydraulic distribution of water flow from the bottom to the surface.

[0042] Domesticated active microorganisms and activated carbon, a carrier of active microorganisms, are introduced into the root systems of the plants 7 planted in the surface planting soil 8. The active microorganisms are aerobic microorganisms, anaerobic microorganisms and / or facultative microorganisms. With this arrangement, each subsurface water ecological purification bed becomes a small sewage treatment plant, which increases the purification effect of the subsurface water ecological purification bed on river water. The microorganisms are cultured on the substrate and cultured and domesticated using water from the river, so that the microorganisms adapt to the water quality characteristics of the river. Active microorganisms are introduced into the soil where the plants grow using activated carbon as a carrier. The amount of microorganisms (including carriers) required for each subsurface water ecological purification bed is about 0.5g.

[0043] The first composite filler layer 10 and the second composite filler layer 9 are composed of composite fillers of different particle sizes, and the composite fillers include serpentine, steel slag, and biological fillers. In this arrangement, the composite fillers are mainly composed of mineral fertilizers, metal smelting byproducts, and ceramsite, and are proportioned according to the water purification requirements. This fully utilizes the excellent permeability of ceramsite, improves the water permeability of the bed, reduces the probability of blockage, and exerts its adsorption performance for ammonia nitrogen. The composite fillers are porous materials with a large specific surface area. After being put into use, microorganisms in the river channel easily grow on their surfaces, thereby forming a biofilm. The microorganisms in the biofilm absorb and decompose organic matter in the water, giving the composite fillers the ability to purify water. The high porosity and large connectivity ensure the system's mass transfer efficiency, which is conducive to promoting the activity of microorganisms within the fillers. Due to the connectivity of the spatial structure, the fillers can be controlled to have three environments: aerobic, anoxic, and facultative.

[0044] Each matrix prefabricated block 4 is equipped with two cable-linking holes. Galvanized steel cables 6 pass through these holes to interconnect adjacent matrix prefabricated blocks 4, forming an interlocking matrix. This interlocking matrix is ​​secured within the river channel via pre-embedded cable loops 5. This arrangement allows for significant flexibility between adjacent matrix prefabricated blocks. While securing the internal filling material of the bed, it also preserves or restores the natural form of rivers and lakes, maintaining or restoring their meandering or branching, thus avoiding or further minimizing human influence on the existing river channel operation.

[0045] The matrix prefabricated blocks are made of low-alkali cement and wood acetate fiber, specifically concrete prefabricated blocks produced by the Ping'an Branch of Qinghai Yike Ecological Technology Co., Ltd., which can effectively improve the vegetation environment of concrete.

[0046] The plants 7 are reeds, yellow iris, duckweed, and / or cattails. In this arrangement, cold-resistant aquatic plants such as yellow iris, duckweed, and cattails suitable for growth in high-altitude plateaus are selected and planted in combination according to water quality characteristics and landscape adaptation requirements. Aquatic plants absorb nutrients in the water, increasing the oxygen content in the water. While fixing carbon and releasing oxygen, they also absorb sediments in the water, such as nitrogen, phosphorus, heavy metals, and organic pollutants, inhibiting the growth of phytoplankton, thereby eliminating pollution, improving the self-purification capacity of the water, and restoring the ecological function of the water. At the same time, they provide habitats and food sources for animals and microorganisms, maintaining species diversity in the waterside zone.

[0047] Example 1:

[0048] The subsurface water ecological purification bed system is used to comprehensively manage the water environment of the section from Runze Bridge upstream of Beichuan River in the Huangshui River Basin to the Datong County sewage treatment plant.

[0049] The starting point is Liming Bridge and the end point is Runze Bridge, with a total length of about 16.8km. According to on-site surveys, there are about 28 large and small outlets (sewage plant outlets, industrial outlets, farmland drainage outlets, and rainwater outlets) along both sides of the river. Therefore, corresponding water collection channels must be set up to collect the outlet water that poses a potential pollution risk to the river along the line into the subsurface culvert ecological purification bed. Within the range of K0+000--K16+828 on the centerline of the river, along the bottom of the river bank slope, 8.8km of new mortar-made stone water collection channels will be set up, with a total of 15 channels (right bank 1# water collection channel K0+223-K0+450, length 227m; left bank 1# water collection channel K0+719-K0+755, length 36m; Right bank 2# water collection channel K0+548-K1+146, length 598m; left bank 2# water collection channel K0+853-K2+238, length 1385m; right bank 2# water collection channel K0+548-K1+146, length 598m; left bank 3# water collection channel K2+336-K3+415, length 1079m; right bank 3# water collection channel K1+244-K1+825, length 581m; left bank 4# water collection channel K 3+513-K4+510, length 997m; right bank 4# water collection channel K1+923-K2+706, length 783m; left bank 5# water collection channel K13+203-K13+645, length 142m; right bank 5# water collection channel K4+653-K5+463, length 810m; left bank 6# water collection channel K13+743-K14+270, length 527m; right bank 6# water collection channel K8+615-K 8+733, length 118m; left bank 7# water collection channel K15+310-K16+100, length 790m; right bank 7# water collection channel K8+831-K9+401, length 570m; right bank 8# water collection channel K15+174-K15+281, length 570m), a total of 15 subsurface culvert ecological purification beds are set up (1# culvert ecological purification bed K0+450-K0+548, effective area 763.14m 2 (right bank); 2# culvert water ecological purification bed K0+775-K0+853, effective area 763.14m 2 (Left bank); 3# culvert water ecological purification bed K1+146-K1+244, effective area 763.14m 2 (Right bank); 4# culvert water ecological purification bed K1+825-K1+923, effective area 763.14m 2 (right bank); 5# culvert water ecological purification bed K2+238-K2+336, effective area 763.14m 2 (Left bank); 6# culvert water ecological purification bed K2+706-K2+804, effective area 763.14m 2(Right bank); 7# culvert water ecological purification bed K3+415-K3+513, effective area 763.14m 2 (Left bank); 8# culvert water ecological purification bed K4+510-K4+608, effective area 763.14m 2 (Left bank); 9# culvert water ecological purification bed K5+463-K5+561, effective area 763.14m 2 (right bank); 10# culvert water ecological purification bed K8+733-K8+831, effective area 763.14m 2 (right bank); 11# culvert water ecological purification bed K9+401-K9+499, effective area 763.14m 2 (Right bank); 12# culvert water ecological purification bed K13+645-K13+743, effective area 763.14m 2 (Left bank); 13# culvert water ecological purification bed K14+270-K14+368, effective area 763.14m 2 (right bank); 14# culvert water ecological purification bed K15+281-K15+379, effective area 763.14m 2 (Right bank); 15# culvert water ecological purification bed K16+100-K16+198, effective area 763.14m 2 The side walls of the water collection channel are constructed with mortar masonry, and the inner side of the channel is plastered with cement mortar. The channel bottom width is 1.5m, and the channel height is 600mm above the riverbed. The side wall foundation is buried at a depth of not less than 2.0m. At the same time, the side wall near the centerline of the river channel is backfilled with loose riprap (starting from a depth of 2.0m), with a D ≥ 30cm, a backfill angle of 45 degrees, and compacted.

[0050] The subsurface culvert ecological purification bed is built close to the river bank foundation and is parallel to the bank in the vertical direction. The side walls are made of reinforced concrete structure with a concrete foundation depth of 0.85m. Stone blocks are backfilled at the bottom of the concrete foundation. The thickness of the stone blocks is not less than 30cm and the total backfill depth of the stone blocks is not less than 1.15m. At the same time, the side walls of the purification bed are backfilled with scattered stones (starting from a burial depth of 2.0m) near the center line of the river channel, with D≥30cm, a backfill angle of 45 degrees, and compaction treatment. On the riprap, a 150mm-thick layer of pebbles (15-18mm in diameter), a 150mm-thick layer of crushed stone (6-15mm in diameter), a 200mm-thick composite filler layer (3-15mm in diameter), a 230mm-thick composite filler layer (0.5-2mm in diameter), a 200mm-thick topsoil layer, and matrix prefabricated blocks 4 were laid in sequence. Adjacent matrix prefabricated blocks 4 were interconnected by galvanized steel cables 6 to form an interlocking matrix. The interlocking matrix was secured within the river channel via pre-embedded steel cable loops 5, and the matrix prefabricated blocks 4 were filled with crushed stone. Plants 7 were planted in the gaps of the interlocking matrix. These plants included yellow iris (20 plants / m2), cattail (6 clumps / m2 or 6 buds / m2), and water hyacinth (2 heads / m2 or 2 piles / m2).

[0051] The composite filler in this embodiment includes serpentine, steel slag and biological filler. The filler has stable biochemical properties, is durable, is non-biodegradable, does not dissolve harmful substances, does not affect biological activity, and has strong corrosion resistance and is durable.

[0052] In this embodiment, plants 7 include yellow calamus, cattail, and water hyacinth. Aquatic plants absorb nutrients in the water, increasing the oxygen content in the water. While fixing carbon and releasing oxygen, they also absorb sediments in the water, such as nitrogen, phosphorus, heavy metals, and organic pollutants, inhibiting the growth of phytoplankton, thereby eliminating pollution, improving the self-purification capacity of the water, and restoring its ecological functions. They also provide habitats and food sources for animals and microorganisms, maintaining species diversity in the waterside zone.

[0053] After one week of operation, the inlet and outlet water quality of the subsurface culvert ecological purification bed wastewater treatment process was self-inspected. After four months of operation, a third-party testing of the inlet and outlet water quality was conducted. Detailed data is shown in the table below. During operation, water samples were collected on-site. Ammonia nitrogen was measured using the Nessler colorimetric method with a visible spectrophotometer (V-5100). COD was measured using the potassium dichromate method with a COD standard digester (HCA-100).

[0054] Table 1 Self-inspection data of water quality at the inlet and outlet of purification bed

[0055]

[0056] Table 2 Third-party testing data of water quality of purification bed inlet and outlet

[0057]

[0058]

[0059] An analysis of the operation and effectiveness of the comprehensive water environment management project in the Huangshui River Basin, from the upstream of Runze Bridge to the Datong County Sewage Treatment Plant, shows that the subsurface flow water ecological purification bed technology can operate stably in high-altitude plateaus. The main indicators of sewage treatment along the river have been improved from Class IV to Class III in the "Surface Water Environmental Quality Standard" (GB 3838-2002). This indicates that this invention is suitable for river ecological management in high-altitude plateaus and can achieve all-weather river water purification capabilities.

[0060] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A subsurface water ecological purification bed system suitable for high altitude and cold areas of plateaus, characterized by: The system consists of several subsurface water culvert ecological purification beds, each of which is surrounded by a reinforced concrete pool wall, and overflow weirs are set between adjacent subsurface water culvert ecological purification beds; The subsurface water ecological purification bed consists of scattered rocks, pebble layer, crushed stone layer, first composite filler layer, second composite filler layer, surface planting soil and matrix prefabricated blocks from bottom to top; The matrix prefabricated blocks are concrete structures with quadrilateral nest holes in the middle. Adjacent matrix prefabricated blocks are connected to each other by galvanized steel cables to form a chain matrix. The gaps in the chain matrix are filled with gravel, and plants are planted in the gaps in the chain matrix. Each matrix prefabricated block is provided with two steel cable connection holes, through which galvanized steel cables pass to connect adjacent matrix prefabricated blocks to form a chain matrix, which is fixed in the river channel by pre-buried steel cable rings; The plants are reed, yellow iris, water calamus and / or cattail.

2. The subsurface water ecological purification bed system suitable for high altitude and cold areas according to claim 1 is characterized in that: The particle size D of the scattered rock is not less than 300 mm.

3. The subsurface water ecological purification bed system suitable for high altitude and cold areas of plateau according to claim 1 is characterized in that: The pebble layer has a particle size of 15-18 mm and a thickness of 150 mm.

4. The subsurface water ecological purification bed system suitable for high altitude and cold areas of plateau according to claim 1 is characterized in that: The particle size of the gravel layer is 6-15 mm and the thickness is 150 mm.

5. The subsurface water ecological purification bed system suitable for high altitude and cold areas of plateau according to claim 1 is characterized in that: The particle size of the first composite filler layer is 3-15 mm and the thickness is 200 mm; the particle size of the second composite filler layer is 0.5-2 mm and the thickness is 230 mm; the thickness of the surface planting soil is 200 mm; and the thickness of the matrix prefabricated block is 120 mm.

6. The subsurface water ecological purification bed system suitable for high altitude and cold areas according to claim 1 is characterized in that: Domesticated active microorganisms and activated carbon, an active microorganism carrier, are introduced into the root systems of plants planted in the surface planting soil.

7. The subsurface water ecological purification bed system suitable for high altitude and cold areas according to claim 6 is characterized in that: The active microorganisms are aerobic microorganisms, anaerobic microorganisms and / or facultative microorganisms.

8. The subsurface water ecological purification bed system suitable for high altitude and cold areas according to claim 1 is characterized in that: The first composite filler layer and the second composite filler layer are composed of composite fillers with different particle sizes, and the composite fillers include serpentine, steel slag and biological fillers.

Images