CN201908002U - Natural aeration vertical subsurface type flow sewage treatment device for artificial wetland - Google Patents

Abstract

The utility model discloses a natural aeration vertical submerged artificial wetland sewage treatment device, which comprises a pretreatment pool, an artificial wetland treatment pool, an advanced treatment pool and a natural circulation pool. The pretreatment pool includes an inner pool and an outer pool. The upper part of the pool is connected to the water distribution pipe in the constructed wetland treatment pool through the water outlet. The constructed wetland treatment pool is composed of composite matrix layers, and is connected to the advanced treatment pool through the clear water outlet. The top of the funnel is connected to the inclined diversion pipe of the natural circulation pool. The inclined diversion pipe is provided with a discharge pipe and a Venturi tube respectively. The inclined diversion pipe is connected to the internal circulation pipe, and the internal circulation pipe is connected to the artificial wetland by the circulation water inlet through the one-way valve. pool. The utility model has the characteristics of high pollution load, strong impact resistance, small footprint, high sewage treatment efficiency, stable operation and low energy consumption, and can effectively improve the treatment efficiency of domestic sewage, especially for nitrogen, phosphorus and organic matter. The treatment efficiency can be widely used in the treatment of domestic sewage in small and medium-sized towns, suburbs, towns and rural areas.

Description

Natural aeration vertical underflow artificial wetland sewage treatment device

1. Technical field

The utility model belongs to the technical field of sewage treatment equipment, and in particular relates to a domestic sewage artificial wetland treatment technology, in particular to a natural aeration vertical underflow artificial wetland sewage which makes better use of natural aeration and strengthens the treatment efficiency of domestic sewage by the artificial wetland system Processing device.

2. Background technology

Domestic sewage has become a major source of pollution in cities and towns. Domestic sewage entering rivers, lakes, reservoirs and other surface water systems will bring pollution to natural water bodies that cannot be ignored. At present, more than 80% of the lakes, rivers, and reservoirs around the cities and towns in China are polluted to varying degrees from urban sewage, which has caused eutrophication of a large number of water systems. Therefore, the comprehensive interception of urban domestic sewage and the Centralized treatment has become the main sewage treatment measures in large and medium-sized cities and towns.

Traditional physicochemical + biochemical process sewage treatment technology has been widely used in the treatment of urban sewage, such as: physical precipitation + chemical coagulation sediment pretreatment + SBR, A ² O, oxidation ditch and other activated sludge microbial processes have been It is widely used in various urban sewage treatment, and the treated sewage can meet the first-class standard of GB 8978 1996. However, due to the high investment and operating costs of traditional domestic treatment processes and the high degree of management specialization, many cities and towns cannot guarantee their long-term stable operation after the construction of sewage treatment plants, so that some sewage treatment plants cannot realize the treatment of urban sewage processing requirements. In addition, some small and medium-sized cities, suburbs, and towns cannot meet the requirements of investing in the construction of traditional sewage treatment plants, so that the daily domestic sewage cannot be treated in time, and it is directly discharged into downstream natural water bodies to cause pollution.

Since the artificial wetland technology was applied in Germany in the 1950s, due to its low investment and operating costs, stable operation, and convenient management, the artificial wetland technology has been widely accepted in different wastewater treatment processes. At present, constructed wetlands have been successfully applied to waste water treatment processes such as domestic sewage, chemical, pharmaceutical, printing and dyeing industries, and garbage seepage, and achieved good application results.

Constructed wetlands can be divided into surface flow wetlands and subsurface flow wetlands, and subsurface flow wetlands include vertical underflow wetlands and horizontal underflow wetlands. Many domestic and foreign research results show that different types of constructed wetlands have great differences in the treatment efficiency of nitrogen, phosphorus and organic matter in domestic sewage. The treatment efficiency of surface flow wetlands for nitrogen, phosphorus and organic matter in domestic sewage is 15-24%, respectively. 12-22% and 18-30%, and the treatment efficiencies of subsurface wetlands for nitrogen, phosphorus and organic matter in domestic sewage are 25-45%, 23-50% and 24-35%, respectively. The overall treatment efficiency of constructed wetlands for domestic sewage is that the treatment efficiency of subsurface wetlands is higher than that of surface flow wetlands, while the treatment efficiency of vertical subsurface wetlands is better than that of horizontal subsurface wetlands.

At the end of the 1980s, constructed wetlands have gradually entered China's sewage treatment and have been well developed. For example, in the 1990s, the Honghu Constructed Wetland System Water Purification Project in Shenzhen, my country, built a high-efficiency vertical flow constructed wetland system to treat the water of the Buji River and surrounding rural domestic sewage, and the effluent could meet the requirements of urban greening water; established at the beginning of this century Yuxi Jiuxi Constructed Wetland is located in Jiuxi Town, Yuxi City, Yunnan Province. By constructing anaerobic sugar, surface flow and subsurface flow artificial emergent plant ponds, etc., the effluent of Xingyun Lake (inferior to the fifth category of water) is effectively treated, and good treatment results have been achieved. However, the traditional constructed wetlands currently built in China generally have low sewage treatment efficiency, low treatment efficiency for nitrogen and phosphorus pollutants, and large land occupation (the daily load of sewage treatment per unit area of constructed wetland is 0.1-0.3t/d), etc. question. Generally speaking, traditional constructed wetlands are not efficient in domestic sewage treatment, especially in the treatment of nitrogen, phosphorus, and organic matter, and occupy a large area. Under normal circumstances, domestic sewage can only meet the secondary standard of GB89781996 after being treated by traditional constructed wetlands.

Utility model content

The purpose of this utility model is to provide a natural aeration vertical with low infrastructure and operating costs, simple process flow, convenient operation and management, load impact resistance, long service life, high sewage treatment efficiency, and water output that can meet the first-class standard of GB 8978 1996. Subsurface flow artificial wetland sewage treatment device.

The purpose of this utility model is achieved in this way: it includes a pretreatment pool, an artificial wetland treatment pool, an advanced treatment pool and a natural circulation pool. The pretreatment pool includes an inner pool and an outer pool. The outer pool, the upper part of the outer pool is connected to the water distribution pipe in the constructed wetland treatment pool through the water outlet, and the constructed wetland treatment pool is composed of composite matrix layers, the bottom of the constructed wetland treatment pool is connected to the advanced treatment pool through the clear water outlet, and the bottom of the advanced treatment pool is Filter packing is set, and a diversion funnel is set on the top of the advanced treatment tank. The top of the diversion funnel is connected to the diversion inclined pipe of the natural circulation pool. The diversion inclined pipe is respectively provided with a discharge pipe and a Venturi tube, and the diversion inclined pipe is connected to the internal circulation pipe. The inner circulation pipe is connected to the artificial wetland treatment pool by the circulation water inlet through the one-way valve.

The pretreatment tank completes the primary treatment through the natural sedimentation of the sewage during the rise of the water level in the outer pool to remove part of the SS in the sewage; the roots of emergent plants in the pretreatment tank fix the nitrogen and phosphorus in the sewage by absorbing the required nutrients Pollutants: The covering effect of phytoplankton makes the outer pool in a relatively anaerobic environment, which can anaerobically degrade organic pollutants in domestic sewage. Stay in the pretreatment pool for 3-5 days to remove some COD (chemical oxygen demand), BOD (biochemical oxygen demand), ammonia nitrogen, TSS (total suspended solids) and other pollutants, and reduce the sewage pollution load entering the constructed wetland treatment pool , Improve the biodegradability of sewage.

The pretreated sewage enters the water distribution pipe of the constructed wetland and submerges from top to bottom to the bottom of the substrate layer of the constructed wetland. The constructed wetland realizes the pollution of nitrogen, phosphorus, organic matter and SS in domestic sewage through physical interception, filtration, chemical reaction and precipitation, etc. The wetland matrix layer with different grain sizes will provide the framework and support for the growth of wetland microorganisms; the constructed wetland matrix layer from top to bottom from fine to coarse can effectively solve the clogging problem of traditional constructed wetlands. The wetland microorganisms formed on the surface of the substrate and the plant root area can degrade organic matter, transform nitrogen-containing pollutants, degrade and aggregate phosphorus-containing pollutants under aerobic and anaerobic conditions, and domestic sewage is treated in the artificial wetland treatment pool. Staying for 1-3 days can effectively remove COD, BOD, nitrogen-containing pollutants, phosphorus-containing pollutants, TSS and other pollutants in sewage. Then the sewage enters the advanced treatment tank, rises to the diversion funnel after being filtered and precipitated by the filter filler, enters the diversion inclined pipe and is discharged through the water outlet, and part of the water passes through the Venturi tube and the internal circulation pipe installed on the diversion inclined pipe , one-way valve and the circulating water inlet in the artificial wetland treatment pool to realize the natural aeration of the sewage in the pretreatment pool to improve the treatment efficiency.

The utility model has the characteristics of high pollution load, strong impact resistance, small footprint, high sewage treatment efficiency, stable operation, low energy consumption, etc., and can effectively improve the treatment efficiency of domestic sewage, especially for nitrogen, phosphorus and organic matter. The treatment efficiency can be widely used in the treatment of domestic sewage in small and medium-sized towns, suburbs, towns and rural areas.

Description of drawings

The accompanying drawing is a schematic diagram of the overall structure of the processing device of the present invention.

In the figure: I-pretreatment pool, II-constructed wetland treatment pool, III-advanced treatment pool, IV-natural circulation pool, 1-inlet pipe, 2-phytoplankton, 3-outer pool, 4-inner pool, 5-outlet Shuikou, 6-emergent plants, 7-water distribution pipe, 8-planting substrate layer, 9-fine-grained substrate layer, 10-medium-grained substrate layer, 11-coarse-grained substrate layer, 12-clear water outlet, 13-filter filler , 14- diversion funnel, 15- diversion inclined pipe, 16- discharge pipe, 17- Venturi tube, 18- internal circulation pipe, 19- one-way valve, 20- circulation water inlet.

Detailed ways

The utility model will be further described below in conjunction with the accompanying drawings, but the utility model is not limited in any way, and any transformation done based on the teaching of the utility model all falls within the protection scope of the utility model.

As shown in the drawings, the utility model includes a pretreatment pool I, a constructed wetland treatment pool II, an advanced treatment pool III and a natural circulation pool IV. The pretreatment pool I includes an inner pool and an outer pool, and the water inlet pipe 1 communicates with the inner pool. , the bottom of the inner pool is connected to the outer pool, and the upper part of the outer pool is connected to the water distribution pipe 7 in the constructed wetland treatment pool II through the water outlet 5. The water outlet 12 is connected to the advanced treatment pool III, the bottom of the advanced treatment pool III is provided with a filter filler 13, the top of the advanced treatment pool III is provided with a diversion funnel 14, and the top of the diversion funnel 14 is connected to the diversion inclined pipe 15 of the natural circulation pool IV, and the diversion inclined pipe 15 is provided with a discharge pipe 16 and a Venturi pipe 17. The diversion inclined pipe 15 is connected to the internal circulation pipe 18, and the internal circulation pipe 18 is connected to the artificial wetland treatment pool II through the circulation water inlet 20 through the check valve 19.

The volume of the inner pool of the pretreatment pool is 1/2-1/4 of the outer pool. The phytoplankton 2 is planted in the pretreatment pond, and the phytoplankton 2 includes one or a combination of water hyacinth, big float and duckweed.

The constructed wetland treatment pool is constructed of square or cylindrical structures, and constructed wetland matrix is laid in the structure pool. The laying of constructed wetland matrix generally includes 2-5 layers, forming a composite layer of constructed wetland matrix that is first thick and then thin from bottom to top.

In the constructed wetland treatment pool III, a coarse-grained substrate layer 11 , a medium-grained substrate layer 10 , a fine-grained substrate layer 9 and a planting substrate layer 8 are arranged sequentially from bottom to top.

The coarse-grained matrix layer 11 is a gravel layer, the medium-grained matrix layer 10 is a ceramsite layer, the fine-grained matrix layer 9 is a cinder layer; the planting matrix layer 8 is a clay layer.

The matrix particle diameter of described coarse-grained matrix layer 11 is 5-10cm, and laying thickness is 20-40cm;

The matrix particle size of the medium-grain matrix layer 10 is 3-5cm, and the laying thickness is 30-50cm;

The matrix particle diameter of described fine-grained matrix layer 9 is 1-3cm, and laying thickness is 20-40cm;

The laying thickness of the planting matrix layer 8 is 10-20cm.

The planting matrix layer 11 is used for planting emergent plants with good pollution resistance, and the planting density is 10-30×10-30 cm. The emergent plants include one or a combination of reeds, wild rice plants, water onions, calamus and cattails.

The water distribution pipe 7 is located between the fine-grained matrix layer 9 and the planting matrix layer 8 .

The diameter of the water distribution pipe 7 is 10-40mm, and the laying distance of the water distribution pipe 7 is 30-80cm.

The filter filler includes fiber balls and/or pebbles.

The working requirements of the utility model:

1. System water intake index: COD<400mg/L, preferably 80-350mg/L; BOD<250mg/L, preferably 50-200mg/L; ammonia nitrogen<60mg/L, preferably 25-45mg/L; total phosphorus<5mg /L, preferably 1.2-3.8mg/L;

2. Clean up the sludge in the pretreatment tank and advanced treatment tank in time, and regularly harvest and salvage emergent plants;

3. Ensure reasonable operating parameters, dredge water distribution pipes, diversion inclined pipes, Venturi pipes, one-way valves, etc. at any time, and regularly inspect or maintain pipeline transmission and distribution systems.

Example one

An example of domestic sewage treatment on a university campus in Kunming, Yunnan Province, with a treatment capacity of 4-12t/d. The pretreatment pool I is circular, with a pool height of 2.5m, an inner pool radius of 0.2m, and an outer pool radius of 0.8m. Plant water hyacinth phytoplankton with a coverage of 50-80%; the size of the artificial wetland treatment pool II is 3×2×2m. From bottom to top, the wetland matrix is gravel (grain size 5-8cm, thickness 30cm), ceramsite (grain size 3-4cm, thickness 40cm), cinder (2-3cm, thickness 40cm) and clay (3-5mm, Thickness 30cm), and plant emergent plants 6 with 20 * 20cm spacing, be Zizania japonica; The size of deep treatment pool III is 1 * 0.5 * 0.5m, the bottom size of middle part square diversion funnel 14 is 1 * 0.5m and the upper guide The inner diameter of the inclined flow pipe 15 is 0.1m, and the inclined flow pipe 15 is connected to the circulating water inlet in the artificial wetland treatment pool II, with a height of 1.3m, so as to realize the internal circulation treatment of sewage.

The sewage is taken from the domestic sewage reservoir, enters the inner layer of the pretreatment pool I from 1 through the submersible pump, and gradually flows to the outer layer by itself, and is discharged from the water outlet 5 after staying for 48 hours. The sewage enters the constructed wetland treatment pool II through the water distribution pipe 7 and is discharged by The clean water flows into the advanced treatment tank III through the clean water outlet 12, and the sewage filtered by the filter filler 13 enters the natural circulation tank through the siphon effect of the diversion inclined pipe 15, and then passes through the Venturi tube 17, the internal circulation tube 18, and the one-way valve 19 in sequence and the circulating water inlet 20 to complete the 48hrs internal circulation treatment, and the treated sewage is discharged from the discharge pipe 16. The removal efficiency of main pollutants is shown in Table 1.

Table 1: Comparison table of domestic sewage purification effect and seasonal differences in this case

It can be seen from Table 1 that the treatment effect of the utility model on campus domestic sewage varies with seasons, the best in summer and the worst in winter, which is due to the lower external temperature in winter and other reasons. Judging from the annual operation status, the removal rate of PO ₄ -P and TP pollutants is between 83-96%, the pollution removal rate of COD is between 72-88%, and the removal rate of NH ₃ -N and TN pollutants The rate is between 53-84%, and the effluent water quality can always meet the first-level discharge standard of GB8978-1996.

Example two

An example of rural domestic sewage treatment in a village in Wenshan Prefecture, Yunnan Province, with a treatment capacity of 6-8t/d. The pretreatment pool I is square, the pool height is 2m, the size of the inner pool is 0.2×0.22m, the size of the outer pool is 0.8×0.8m, and the water surface is planted with water hyacinth phytoplankton with 60% coverage; the artificial wetland treatment pool II is 2.5m in size. ×2×1.6m. Wetland substrates from bottom to top are gravel (grain size 5-8cm, thickness 30cm), ceramsite (grain size 3-4cm, thickness 30cm), cinder (2-3cm, thickness 30cm) and clay (3-5mm, Thickness 20cm), the emergent plant Acorus calamus is planted at 15×15cm intervals in the clay matrix; the size of the deep treatment pool III is 0.6×0.4×0.5m, the bottom size of the square diversion funnel in the middle is 0.6×0.4m and the inner diameter of the upper inclined pipe is 0.1 m, the diversion inclined pipe 15 is connected to the water inlet 20 of the constructed wetland treatment pool, with a height of 1.1 m, so as to realize the internal circulation treatment of sewage.

The sewage is taken from the domestic sewage storage tank, enters the inner layer of the pretreatment pool I from 1 through the submersible pump, and gradually flows to the outer layer by itself, and is discharged from the water outlet 5 after staying for 24 hours. The sewage enters the artificial wetland treatment pool II through the water distribution pipe 7 and is discharged by The clean water flows into the advanced treatment tank III through the clean water outlet 12, and the sewage filtered by the filter filler 13 enters the natural circulation tank through the siphon effect of the diversion inclined pipe 15, and then passes through the Venturi tube 17, the internal circulation tube 18, and the one-way valve 19 in sequence and the circulating water inlet 20 to complete the 72hrs internal circulation treatment, and the treated sewage is discharged from the discharge pipe 16. The removal effect of main pollutants is shown in Table 2.

Table 2: Comparison table of domestic sewage purification effect and seasonal differences in this case

It can be seen from Table 2 that the effect of the utility model on the treatment of rural domestic sewage varies with seasons, the best in summer and the worst in winter, which is due to the lower external temperature in winter and other reasons. Judging from the annual operation status of this constructed wetland, the removal rate of PO4-P and TP pollutants is between 85-93%, the pollution removal rate of COD is between 63-91%, and the removal rate of NH3-N and TN pollutants The removal rate is between 53-78%, and the effluent water quality can always meet the first-level discharge standard of GB 8978-1996.

Advantages of the utility model

1. The utility model integrates the natural circulation device and the artificial wetland treatment device, which is beneficial to the formation and reproduction of wetland microorganisms, and the degradation and removal of pollutants in domestic sewage; from top to bottom, the composite matrix layer and vertical The subsurface flow method effectively overcomes the clogging problem of traditional constructed wetlands.

2. The utility model applies the principle of siphon to the deep treatment tank to realize the repeated treatment of the internal circulation of domestic sewage; at the same time, the introduction of a Venturi tube realizes the natural aeration process of domestic sewage, so that the circulation enters the artificial wetland treatment tank The dissolved oxygen content of the sewage is 3-5 times higher than that of traditional constructed wetlands, thus strengthening the aerobic treatment of the constructed wetland system.

3. The integrated design of the utility model has the advantages of simple process, little influence by external conditions, strong impact resistance, stable effluent quality, which can meet the treatment requirements of urban and rural domestic sewage, and can meet the first-level discharge standard of GB 8978-1996.

4. The utility model has low infrastructure cost (800-2000 yuan/t), less equipment purchase (only several high-pressure pumps, sewage distribution pipes and delivery pipes are needed), flexible operation, convenient maintenance and management, no need to add chemical reagents, and treatment The cost is only 10-40% of the conventional treatment method (0.03-0.1 yuan/t), and the service life is as long as more than 10 years.

5. The utility model is very suitable for my country's national conditions, and can be widely used in the treatment of point source domestic sewage with small and scattered sewage production in suburbs, towns and rural areas.

Claims (8)

1. A naturally aerated vertical underflow constructed wetland sewage treatment device, comprising a pretreatment pond (I), a constructed wetland treatment pond (II), an advanced treatment pond (III) and a natural circulation pond (IV), characterized in that: Described pretreatment pond (1) comprises inner pond (4) and outer pond (3), water inlet pipe (1) communicates with inner pond (4), inner pond (4) bottom communicates with outer pond, and outer pond (3) top passes water outlet (5) connected to the water distribution pipe (7) in the constructed wetland treatment pool (II), the described constructed wetland treatment pool (II) is composed of a combination of composite matrix layers, and the bottom of the constructed wetland treatment pool (II) passes through the clear water outlet (12 ) is connected to the advanced treatment pool (III), the bottom of the advanced treatment pool (III) is provided with filter packing (13), the top of the advanced treatment pool (III) is provided with a diversion funnel (14), and the top of the diversion funnel (14) is connected to the natural circulation pool ( IV) diversion inclined pipe (15), discharge pipe (16) and Venturi tube (17) are respectively arranged on the diversion inclined pipe (15), and diversion inclined pipe (15) communicates with internal circulation pipe (18), and the inner The circulation pipe (18) is connected to the artificial wetland treatment pool (II) through the one-way valve (19) and the circulation water inlet (20). 2. the natural aeration vertical underflow type constructed wetland sewage treatment device according to claim 1 is characterized in that: the inner pool (3) volume of the described pretreatment pool (1) is 1/2-2 of the outer pool (4). 1/4; Phytoplankton (2) is planted in the pretreatment pond (I), and the phytoplankton includes one or more combinations of water hyacinth, big float and duckweed. 3. The natural aeration vertical underflow constructed wetland sewage treatment device according to claim 1, characterized in that: in the described constructed wetland treatment pool (II), a coarse-grained matrix layer (11), Medium grain matrix layer (10), fine grain matrix layer (9) and planting matrix layer (8). 4. The natural aeration vertical underflow type constructed wetland sewage treatment device according to claim 3, characterized in that: the coarse-grained matrix layer (11) is a gravel layer, and the medium-grained matrix layer (10) is For the ceramsite layer, the fine-grained substrate layer (9) is a cinder layer; the planting substrate layer (8) is a clay layer. 5. The naturally aerated vertical underflow constructed wetland sewage treatment device according to claim 3 or 4, characterized in that: the substrate particle diameter of the coarse-grained substrate layer (11) is 5-10 cm, and the laying thickness is 20 cm. -40cm; the matrix particle diameter of the described medium-grain matrix layer (10) is 3-5cm, and the laying thickness is 30-50cm; the matrix particle diameter of the described fine-grain matrix layer (9) is 1-3cm, and the laying thickness 20-40cm; the laying thickness of the planting matrix layer (8) is 10-20cm. 6. The natural aeration vertical underflow constructed wetland sewage treatment device according to claim 3 or 4, characterized in that: the planting matrix layer (8) is planted with emergent plants (6) with good pollution resistance, planted The density is 10-30×10-30 cm, and the emergent plants include one or a combination of reeds, wild rice plants, water onions, calamus and cattails. 7. The naturally aerated vertical underflow constructed wetland sewage treatment device according to claim 1, characterized in that: the water distribution pipe (7) is located between the fine-grained substrate layer (9) and the planting substrate layer (8) . 8. The natural aeration vertical underflow artificial wetland sewage treatment device according to claim 1 or 7, characterized in that: the diameter of the water distribution pipe (7) is 10-40mm, and the laying distance of the water distribution pipe (7) It is 30-80cm. the

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