WO2024217261A1

WO2024217261A1 - Unpowered buried vertical flow wetland rural domestic sewage treatment apparatus and method

Info

Publication number: WO2024217261A1
Application number: PCT/CN2024/085134
Authority: WO
Inventors: 邱建贺; 周国彪; 易旭超; 刘鸿藜; 翁雯; 宁媚艳
Original assignee: 玉凰生态科技股份有限公司
Priority date: 2023-04-18
Filing date: 2024-04-01
Publication date: 2024-10-24
Also published as: CN116425346A; CN116425346B; CN116903186A

Abstract

Disclosed in the present invention are an unpowered buried vertical flow wetland rural domestic sewage treatment apparatus and method. The apparatus comprises a main box body and a composite vertical flow wetland system, wherein the main box body is composed of a sedimentation tank, an anaerobic tank and an anoxic tank which are sequentially in communication with each other; the composite vertical flow wetland system is composed of a subsystem A and a subsystem B each comprising a subsystem tank body, a water intake tank, an intermediate tank and a water level adjusting tank are arranged in sequence in each subsystem tank body, and a filler module is provided in each of the water intake tanks and the intermediate tanks; and an alternate drainage system is arranged between the water level adjusting tank of the subsystem A and the water level adjusting tank of the subsystem B. In the present invention, sedimentation treatment, anaerobic treatment and anoxic treatment of sewage are achieved in an integrated enclosed structure, the sewage can be buried underground for treatment, thus environmental pollution is reduced, and the occupied area is reduced; and the apparatus and the method of the present invention have the advantages of being easy to manage and operate, free of energy consumption, free of power and stable in effluent quality.

Description

Unpowered underground vertical flow wetland rural domestic sewage treatment device and method

Technical Field

The invention relates to the technical field of sewage treatment, and in particular to an unpowered underground vertical flow wetland rural domestic sewage treatment device.

Background Art

At present, rural domestic sewage is large in volume and widespread, and is dispersed and difficult to be collected. Its quantity, composition, and pollutant concentration are related to the living habits, living standards, and water resource enjoyment of residents. In the past decade, with the increase in nitrogen and phosphorus content in rural domestic sewage, the eutrophication of water bodies has been caused and aggravated, and the water quality of receiving water bodies has seriously deteriorated. Due to the continuous aggravation of water pollution, the rural water environment has deteriorated day by day, which not only causes a reduction in crop yields, but also directly threatens the health of the vast number of farmers.

At the same time, since most rural areas have weak economic foundations and a shortage of technical personnel, traditional sewage treatment technologies and equipment require professional technicians to operate and consume certain energy costs. Traditional sewage treatment equipment and devices are easily abandoned in rural areas and become decorations, and cannot play a good role.

The existing underground integrated rural sewage treatment equipment requires many devices, usually requiring the installation of multi-stage pumps for lifting and reflux, which not only occupies a large area, is inconvenient to manage, and is prone to failure. In addition, due to the structural influence, the buried ground is shallow, which generally cannot meet the requirements of gravity water inlet. It is necessary to set up a water collection well for lifting, and there is little soil covering the top of the pool, which makes it difficult to make secondary comprehensive utilization. The area above the pool is affected by pipelines, equipment, inspection wells, etc., and it is impossible to make an artificial wetland directly above the pool.

At present, vertical flow wetland systems are generally used for sewage treatment. However, traditional vertical flow wetland systems are prone to clogging, mainly because the particle size of the filler matrix in the system is generally fine at the top and large at the bottom. The microbial secretions in the system and the sediment on the surface of the filler are easy to block the smaller particle gaps on the top of the filler, and the air on the top layer is difficult to enter the system, and the gas produced by the biochemical reaction of microorganisms in the system is also difficult to get out, thus affecting the sewage treatment efficiency of the entire wetland system. Over time, the entire system becomes hardened and needs to be cleaned as a whole, which costs a lot of manpower, material resources and time, affecting the continuous operation of the system.

Compared with sewage treatment devices on the ground, traditional underground sewage treatment devices have the advantages of less footprint, better environmental benefits, reduced NIMBY conflicts, and realization of land resource sharing. However, problems such as high construction and operation costs and difficulty in management of underground sewage treatment systems have restricted the development of traditional underground sewage treatment devices.

In view of the above technical problems in rural domestic sewage treatment, it is necessary to develop a non-powered underground vertical flow wetland rural domestic sewage treatment device suitable for the current situation in rural areas.

Technical issues

In order to solve the problems existing in the prior art, the purpose of the present invention is to provide a non-powered underground vertical flow wetland rural domestic sewage treatment device and method, which can effectively solve the problem of domestic sewage treatment in rural areas. The sewage can be buried underground to reduce environmental pollution and reduce the floor area. At the same time, the device and method of the present invention have the advantages of easy management and operation, not easy to be blocked, no energy consumption, no power, and stable effluent water quality.

Technical Solutions

The present invention proposes the following technical solution: a non-powered underground vertical flow wetland rural domestic sewage treatment device, comprising a main box and a composite vertical flow wetland system, wherein the main box is composed of a sedimentation tank, an anaerobic tank, and an anoxic tank connected in sequence;

The main box body is provided with a partition plate 1 and a partition plate 2 to separate the main box body into a sedimentation tank, an anaerobic tank, and an anoxic tank; the sedimentation tank and the anaerobic tank are connected through an opening 1 provided at the upper end of the partition plate 1, and the anaerobic tank and the anoxic tank are connected through an opening 2 provided at the bottom of the partition plate 2, and pipelines are provided at the opening 1 and the opening 2;

The anaerobic tank and the anoxic tank are connected by the opening two provided at the bottom of the partition two. The anaerobic tank and the anoxic tank are connected by water from the bottom of the tank. The oil-containing suspended matter in the sewage entering the anaerobic tank floats on the water surface of the anaerobic tank and is decomposed through a longer residence time. The fully decomposed muddy and water matter enters the anoxic tank through the through holes at the lower ends of the anaerobic tank and the anoxic tank through sedimentation. The sewage in the anoxic tank is separated into mud and water. After decomposition, the solid pollutants sink to the bottom of the tank, and the liquid part flows out of the anoxic tank.

The anaerobic tank is provided with a plurality of filler racks and a plurality of baffle plates 1 and 2. The baffle plate 1 is bent along the sewage flow direction near the bottom of the anaerobic tank, and there is a gap between the baffle plate 1 and the bottom of the anaerobic tank. The baffle plate 2 is vertically arranged on the bottom of the anaerobic tank and in contact with the bottom of the anaerobic tank. The height of the baffle plate 1 is higher than the opening 1, and the height of the baffle plate 2 is lower than the opening 1. The filler rack is arranged between the baffle plate 1 and the baffle plate 2, and a soft filler group is arranged on the filler rack;

By installing a soft filler group on the filler rack, the attachment area of microorganisms is increased. Through the design of baffle 1 and baffle 2, sewage is fully in contact with the soft filler on the soft filler group to prevent short-flow. The biofilm attached to the soft filler can treat sewage more effectively.

The composite vertical flow wetland system consists of two parallel subsystems A and B, each of which includes a subsystem pool body, each of which is provided with five layers of filler matrix filter material layers, the top four layers of the filler matrix filter material layers are modularly designed, and a number of square stainless steel mesh boxes are used to load four layers of fillers, each stainless steel mesh box is a filler module, and the bottom of the filler module is a gravel layer.

Furthermore, the two subsystem tank bodies are sequentially provided with a water inlet tank, an intermediate tank and a water level regulating tank, and the filler module is provided in the middle part of the water inlet tank and the intermediate tank;

A partition three is provided between the water inlet pool and the intermediate pool, the bottom of the partition three is flush with the bottom of the filler module, a partition four is provided between the water level regulating pool and the intermediate pool, the bottom end of the partition four is in contact with the bottom of the subsystem pool body, and a plurality of through holes are opened at the bottom of the partition four;

Aquatic plants are planted on the filler module between the partition three and the partition four, and the aquatic plants are at least one of aquatic canna, cattail, pennywort, and foxtail algae.

Two alternating drainage systems are provided between the two water level regulating pools;

An overflow outlet pipe is provided between the water level regulating tank and the intermediate tank, the overflow outlet pipe is composed of a straight pipe and a curved pipe, the straight pipe of the overflow outlet pipe passes through the partition plate 4 and is connected to the intermediate tank, and is provided above the filler module, and an extended drain pipe is provided at the lower end of the water level regulating tank in the water outlet direction, and the extended drain pipe passes through the water level regulating tank;

The anoxic pool is connected to the water inlet pool via a water distribution pipe, and the water distribution pipe is arranged above the filler module.

Furthermore, the main box body is an integrated structure, and inspection well 1 and inspection well 2 are arranged on the top of the main box body. Inspection well 1 is arranged between the sedimentation tank and the anaerobic tank, and inspection well 2 is arranged between the anaerobic tank and the anoxic tank; inspection well 1 and inspection well 2 are arranged near partition 1 and partition 2, and top hole brickwork and manhole covers are provided on inspection well 1 and inspection well 2; the main box body, top hole brickwork and manhole covers form a closed structure.

Through the structural design of inspection well 1 and inspection well 2, it is convenient to check the sewage treatment conditions in the sedimentation tank and the anoxic tank.

Furthermore, the alternating drainage system is composed of a water level detection structure and a drainage structure, the water level detection structure is arranged at the upper end of the water level regulating pool, and the drainage structure is arranged at the lower end of the water level regulating pool; the water level detection structure of subsystem A is connected to the drainage structure of subsystem B, and the detection structure of subsystem B is connected to the drainage structure of subsystem A, a pool pipe is arranged between the water level regulating pool of subsystem A and the water level regulating pool of subsystem B, the water level detection structure of subsystem A is connected to the drainage structure of subsystem B through a connecting cable 2, and the connecting cable 2 passes through the pool pipe, and pulleys 1 are arranged on both sides of the pool pipe below the connecting cable 2; the water level detection structure includes a float, a float Connecting rod, the float is connected to one end of the float connecting rod, a float connecting rod rotating shaft is arranged in the middle of the float connecting rod, and the end of the float connecting rod away from the float is connected to the second connecting rope; the drainage structure includes a balance rod, a balance rod rotating shaft, a slip ring, a second pulley, and a water outlet pipe cover, the balance rod is connected to the float connecting rod through the second connecting rope, a balance rod rotating shaft is arranged in the middle of the balance rod, the end of the balance rod away from the second connecting rope is connected to the first connecting rope, the end of the first connecting rope away from the balance rod is connected to the water outlet pipe cover, the water outlet pipe cover is arranged just above the extended drainage pipe, and a slip ring is arranged on one side of the balance rod connected to the first connecting rope; a second pulley is arranged between the upper end of the first connecting rope and the balance rod, and a third pulley is arranged between the lower end of the first connecting rope and the top of the water outlet pipe cover.

Through the design of the above alternating drainage system, alternating drainage of subsystem A and subsystem B can be achieved; when the water level regulating pool is full, the water can also be discharged through the overflow outlet pipe.

Alternating drainage mechanism of subsystem A and subsystem B: when the float of subsystem B floats up due to full water in the water level regulating tank, one side of the balance rod connected to the connecting cable 2 is driven by the float connecting rod and the float connecting rod rotating shaft to move upward through the balance rod rotating shaft, and the other side of the balance rod moves downward through the balance rod rotating shaft, and the slip ring slides leftward toward the connecting cable 1, and the outlet pipe cover is lifted by the gravity of the connecting cable 1 and the slip ring, and the water in the water level regulating tank of subsystem A is discharged through the extended drain pipe. When the water in the water level regulating tank of subsystem A is drained, the outlet pipe cover of subsystem A loses the buoyancy of the water, and is moved downward by the gravity of the outlet pipe cover itself to cover the extended drain again. Subsystem A begins to accumulate water under the inflow of water from the water distribution pipe. When subsystem A is full of water, the water level detection structure in the water level regulating tank of subsystem A and the drainage structure in the water level regulating tank of subsystem B trigger and lift the outlet pipe cover in the water level regulating tank of subsystem B, and subsystem B is drained. In the manner described above, subsystem A and subsystem B drain alternately.

The composite vertical flow wetland system adopts the setting of alternating full drainage of subsystems A and B. After full drainage, air enters the system to aerate and oxygenate the moist microbial film on the surface of the system filler matrix. The oxygenation inside subsystems A and B is carried out alternately without the need for power.

Furthermore, the extended drainage pipe is composed of a curved pipe 1, a straight pipe 1, a curved pipe 2 and a straight pipe 2, the straight pipe 1 runs through one end of the water level regulating tank, and the length of the straight pipe 2 is 3.5-4 times the length of the straight pipe 1.

When the device of the present invention is draining water, the water inflow of the water distribution pipe does not stop. The system lengthens the drainage pipe to increase the drainage pressure in a natural way, thereby increasing the drainage. The water in the system is emptied by large drainage and small water inflow. Air enters the system while keeping it moist, thereby increasing the oxygen dissolved in the water in the system.

Since subsystems A and B are connected to extended drain pipes respectively, the outlet pipe covers are not activated until subsystems A and B are full of water. The extended drain pipes increase the water level difference in the system and the drainage pressure, thereby driving the aging and peeling biofilm in the wetland system and the sediments settled at the bottom of the system out of the system during drainage to prevent clogging.

Furthermore, there are several packing modules, each of which is composed of four layers of packing from top to bottom, and the four packing layers are, from top to bottom, a guami stone layer, a small round ceramsite layer, a zeolite layer, and a large round ceramsite layer.

Furthermore, the specifications of the packing layer are as follows: the melon stone layer is 150 mm thick and the particle size is 5-10 mm; the small round ceramsite layer is 200 mm thick and the particle size is 3-10 mm; the zeolite layer is 300 mm thick and the particle size is 10-20 mm; the large round ceramsite layer is 200 mm thick and the particle size is 20-40 mm; the gravel layer is 350 mm thick and the particle size is 30-50 mm.

Since rural domestic sewage is large in volume and widespread and dispersed, its quantity, composition, and pollutant concentration are related to the seasonal period, living habits, living standards, and water resource conditions of local residents. The pH value of the sewage produced varies depending on the conditions in different rural areas and seasonal periods. There are two types of filler modules designed in the composite vertical flow wetland system, namely filler module No. 1 and filler module No. 2.

Furthermore, the filler module is a No. 1 filler module, and the No. 1 filler module is a guami stone layer, an acidic small round ceramsite layer, a zeolite layer, and an acidic large round ceramsite layer.

Furthermore, the filler module is a No. 2 filler module, and the No. 2 filler module is a guami stone layer, an alkaline small round ceramsite layer, a zeolite layer, and an alkaline large round ceramsite layer.

Furthermore, when the pH value of the sewage is less than or equal to 8, a No. 1 filler module is installed, and when the pH value of the sewage is greater than 8, a No. 2 filler module is installed.

Different metal ions will react with phosphorus to generate precipitation in different ways under different pH conditions. Different filler modules are designed. According to different rural areas and different seasonal periods, the filler modules of the system device are installed or replaced by detecting the pH properties of the sewage to improve the effect of the filler module reacting with phosphorus to generate precipitation under different pH sewage conditions. Therefore, the desired effect can be achieved with a smaller device size, smaller land area and construction cost.

Furthermore, it also includes a mesh pond, which is connected to the sedimentation tank by a pipeline, a mesh plate is arranged in the mesh pond, grilles are evenly arranged on the mesh plate, a top plate is arranged on the top of the mesh pond to completely cover the mesh pond, a sewage interception pipe is arranged at the water inlet of the mesh pond, and an outlet water collection tank is arranged below the overflow outlet pipe and the extended drain pipe.

Furthermore, the main box and the subsystem tank are integrally formed of glass fiber reinforced plastics, which can effectively prevent sewage from leaking and contaminating groundwater.

A first concrete cushion layer is arranged at the bottom of the mesh pool, a second concrete cushion layer is arranged at the bottom of the main box and the composite vertical flow wetland system, a third concrete cushion layer is arranged on the side of the water level regulating tank connected to the extended drainage pipe, and the height of the bottom of the mesh pool is arranged higher than the bottom of the main box and the subsystem pool body.

The concrete cushion layer 1, concrete cushion layer 2, the bottom of the main box body and the bottom of the subsystem pool body are filled with medium-coarse sand, and the gap between the side of the main box body opposite to the subsystem pool body and the side gap between the concrete cushion layer 3 and the subsystem pool body are filled with plain soil.

Through the design of the concrete cushion layer 1, the concrete cushion layer 2 and the concrete cushion layer 3, the device can be buried in the ground more stably and firmly.

Furthermore, lawn is planted on the soil surface above the main box.

Furthermore, the unpowered buried vertical flow wetland rural domestic sewage treatment device also includes a sewage collection device, which includes a sewage collection pipe and a sewage collection well connected to farmers. The sewage collection device is connected to the sewage interception pipe set at the water inlet of the grid pool. The collected farmers' sewage includes black water and gray water of the farmers. Black water refers to the effluent from the farmers' septic tanks, and gray water refers to the sewage discharged from the farmers' daily life.

The present invention is based on the local conditions in rural areas and is divided into multiple small areas. The sewage collection pipes and sewage collection wells are arranged from high to low along the sewage flow direction using the terrain. There is no need to set up a water pump, no need to consume electricity, and energy is saved, which is suitable for rural areas.

The present invention also discloses a method for treating rural domestic sewage in an underground vertical flow wetland, which uses the above-mentioned unpowered underground vertical flow wetland rural domestic sewage treatment device for treatment, and the steps include:

S1. Rural domestic sewage is discharged into the tertiary septic tank, and the principles of sedimentation and anaerobic fermentation are used to remove suspended organic matter in domestic sewage;

S2. Sewage collection device collects sewage: collects domestic sewage and/or gray water overflowing from septic tanks of each household and puts them into the grid tank for treatment;

S3. Sedimentation tank sedimentation: The sewage collected in step S2 is precipitated in a sedimentation tank, the sedimentation tank adopts a vertical sedimentation tank, the hydraulic retention time is 2h, and the remaining suspended organic matter in the domestic sewage is removed;

S4. Anaerobic tank treatment: The sewage treated in step S3 flows into the anaerobic tank, and anaerobic biofilm is used to remove the organic pollutants in the sewage in colloidal and dissolved states. The filler is suspended by a hanger set in the anaerobic tank, and soft filler or semi-soft filler is used to provide a solid surface for the attachment and growth of anaerobic microorganisms, so that a biofilm is formed on the surface of the filler;

S5. Anoxic tank treatment: The sewage after anaerobic treatment in step S4 is passed into anoxic tank for anoxic treatment;

S6. Composite vertical flow wetland system treatment: The sewage treated in the anoxic tank is discharged through the water distribution pipe to the inlet pool of the composite vertical flow wetland system. The sewage is treated by the filler module and gravel layer in the composite vertical flow wetland system and infiltrates into the bottom layer of the wetland. The water discharged from the composite vertical flow wetland system meets the first-level standard of Guangdong Province's Rural Domestic Wastewater Treatment Discharge Standard (DB44/2208-2019);

S7. Tail water resource utilization: The tail water treated and purified in step S6 is discharged to the effluent collection pool through the extended drainage pipe, and the excess purified tail water flows out to the effluent collection pool through the overflow outlet pipe. The water collected in the effluent collection pool can be used for agricultural irrigation.

The mechanism of the composite vertical flow wetland system: the baffle three set in the subsystem pool body does not touch the bottom of the pool. The bottom of baffle three is connected to reserve a gravel layer. The bottom of baffle four has a through hole to guide the water in the filler area into the water level regulating pool. The water from the water distribution pipe passes through the filler module in front of baffle three, flows vertically downward, enters the gravel layer at the bottom, and then flows vertically upward, flows through the filler module between baffles three and four, and then flows out through the overflow outlet pipe. The process of water flowing vertically downward and vertically upward through the filler module is called composite vertical flow.

Beneficial Effects

The present invention has the following beneficial effects:

1. The present invention realizes the sedimentation treatment, anaerobic treatment and anoxic treatment of sewage in an integrated closed structure. The sewage treatment can be buried underground to reduce environmental pollution and floor space. In a closed state, the waste gas generated can be degraded by microorganisms in the water to reduce the generation of odor. At the same time, the present invention adopts an integrated non-powered and low-management design, which has the advantages of low investment and operating costs, simple operation and maintenance while ensuring the treatment effect.

2. The composite vertical flow wetland system designed by the present invention integrates the physical, chemical and biological effects on sewage treatment through the design of the filler modules of the water inlet pool and the intermediate pool and the design of the aquatic plant area on the filler modules of the intermediate pool. It uses the different functions of plants and fillers to carry out biological nitrogen and phosphorus removal, and remove pollutants such as CODCr, BOD, and SS at the same time. After the composite vertical flow wetland system matures, a biofilm will form on the surface of the filler and the root system of the plant due to the growth of a large number of microorganisms. When sewage flows through the biofilm, a large amount of SS is blocked and intercepted by the filler and the root system of the plant, and organic pollutants are removed through the absorption, assimilation and alienation of the biofilm. Finally, the composite vertical flow wetland system replaces the filler module or harvests the planted plants to achieve the final removal of pollutants.

3. The present invention designs the composite vertical flow wetland system into a five-layer filter material layer, and comprehensively utilizes the ability of microbial degradation, plant absorption, and filter material matrix adsorption to remove pollutants in sewage; and because the upper four layers adopt a modular filler design, it is convenient to clean and replace regularly. The filler module design using multiple stainless steel mesh boxes of the same size to load multi-layer fillers can achieve uniform size production, convenient mass production, convenient transportation, and quick installation. When one of the filler modules is damaged or blocked, only the damaged or blocked filler module needs to be replaced to reduce maintenance costs. At the same time, the use of module replacement can simplify the scale of operations, streamline personnel, and shorten cleaning time, thereby shortening the shutdown time of the device system and improving the efficiency of the device system; the bottom layer is a large-grain gravel layer, which is thicker and heavier, and the pores between the gravels are large and not easy to clog.

4. The present invention solves the two main problems of low treatment efficiency and easy blockage in the wetland system through the design of the alternating drainage system and the lengthened drainage pipe. Through the design of the alternating drainage system, the oxygenation in the two subsystems A and B is carried out alternately without power; through the design of the lengthened drainage pipe, the water level difference in the system is increased, and the drainage pressure is increased, so that the aged and peeled biofilm in the wetland system and the sediments deposited at the bottom of the system are driven out of the system during drainage to prevent clogging.

5. The device of the present invention is designed with through holes in the filler module and the partition plate 4 of the water level regulating tank. When draining water from the lower part of the filler, the obstructions and gases that may cause blockage are taken away from the lower part, and air is introduced more effectively to increase the oxygen in the system and prevent the system from being blocked and hardened.

6. The sewage treatment of the present invention is composed of a sedimentation tank, an anaerobic tank, an anoxic tank and a composite vertical flow wetland system in series, and has a strong ability to resist shock loads. Domestic sewage enters the sedimentation tank, anaerobic tank, and anoxic tank, intercepts most of the organic matter, and is decomposed into small molecular organic matter under the action of anaerobic hydrolysis. The small molecular organic pollutants are removed in the composite vertical flow wetland system through filtration, adsorption, plant absorption and biodegradation. The process is simple, has no power loss, is easy to maintain and manage, basically does not generate operating expenses, and the effluent water quality is stable.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 is a schematic diagram of the three-dimensional structure of the present invention;

FIG2 is a front cross-sectional view of the present invention;

FIG3 is a schematic diagram of the internal structure of an anaerobic tank according to the present invention;

FIG4 is a schematic diagram of the structure of one of the alternating drainage systems between subsystem A and subsystem B;

Fig. 5 is a top view of the present invention;

FIG6 is a process flow chart of the present invention;

Among them, 1-grid tank, 11-concrete cushion layer 1, 12-concrete cushion layer 2, 13-concrete cushion layer 3, 14-top plate, 2-sedimentation tank, 21-inspection well 1, 22-inspection well 2, 23-top hole brickwork, 24-well cover, 3-anaerobic tank, 31-partition 1, 32-partition 2, 33-filling rack, 34-baffle 1, 35-baffle 2, 36-soft filler group, 4-anoxic tank, 5-subsystem tank body, 51-inlet tank, 52-intermediate tank, 53-water level regulating tank, 54-partition 3, 55 ‑gravel layer, 56‑partition plate four, 57‑overflow outlet pipe, 58‑filling module, 6‑water distribution pipe, 7‑extended drainage pipe, 71‑straight pipe one, 72‑straight pipe two, 8‑water collection tank, 101‑float, 102‑float connecting rod, 103‑float connecting rod shaft, 104‑pulley one, 105‑pulley two, 106‑cable two, 107‑cable one, 108‑slip ring, 109‑balance rod, 110‑balance rod shaft, 111‑outlet pipe cover, 112‑pool pipe, 113‑pulley three.

Best Mode for Carrying Out the Invention

The present invention is further described below through the accompanying drawings and embodiments, but they are not intended to limit the present invention.

Embodiment 1: Referring to FIG. 1-FIG. 5, the present invention provides a non-powered underground vertical flow wetland rural domestic sewage treatment device, comprising a main box and a composite vertical flow wetland system, wherein the main box is composed of a sedimentation tank 2, an anaerobic tank 3, and an anoxic tank 4 connected in sequence;

A partition 1 31 and a partition 2 32 are provided in the main box body to separate the main box body into a sedimentation tank 2, an anaerobic tank 3, and an anoxic tank 4; the sedimentation tank 2 and the anaerobic tank 3 are connected through an opening 1 provided at the upper end of the partition 1 31, and the anaerobic tank 3 and the anoxic tank 4 are connected through an opening 2 provided at the bottom of the partition 2 32, and pipes are provided at both the opening 1 and the opening 2;

The anaerobic tank 3 and the anoxic tank 4 are connected by the opening 2 provided at the bottom of the partition 2 32. The anaerobic tank 3 and the anoxic tank 4 are connected by water from the bottom of the tank. The oil-containing suspended matter in the sewage entering the anaerobic tank 3 floats on the water surface of the anaerobic tank 3 and is decomposed through a longer residence time. The fully decomposed muddy and watery matter enters the anoxic tank 4 through the through holes at the lower ends of the anaerobic tank 3 and the anoxic tank 4 through sedimentation. The sewage in the anoxic tank 4 is separated into mud and water. After decomposition, the solid pollutants sink to the bottom of the tank, and the liquid part flows out of the anoxic tank.

A plurality of filler racks 33, a plurality of baffle plates 1 34, and a plurality of baffle plates 2 35 are arranged in the anaerobic tank 3. The baffle plates 1 34 are bent along the flow direction of sewage near the bottom of the anaerobic tank 3, and there is a gap between the baffle plates 1 34 and the bottom of the anaerobic tank 3. The baffle plates 2 35 are vertically arranged on the bottom of the anaerobic tank 3 and contact the bottom of the anaerobic tank 3. The height of the baffle plates 1 34 is higher than the opening 1, and the height of the baffle plates 2 35 is lower than the opening 1. The filler rack 33 is arranged between the baffle plates 1 34 and the baffle plates 2 35, and a soft filler group 36 is arranged on the filler rack 33.

By installing a soft filler group 36 on the filler rack 33, the attachment area of microorganisms is increased. Through the design of baffle 34 one and baffle 2 35, the sewage is fully in contact with the soft filler on the soft filler group to prevent short-circuiting. The biofilm attached to the soft filler can treat the sewage more effectively.

The composite vertical flow wetland system consists of two parallel subsystems A and B. Both subsystems A and B include a subsystem pool body 5. Each subsystem pool body 5 is provided with five layers of filler matrix filter material layers. The upper four layers of the filler matrix filter material layer are modularly designed. A plurality of square stainless steel mesh boxes are used to load four layers of filler. Each stainless steel mesh box is a filler module 58, and the bottom of the filler module 58 is a gravel layer 55.

Furthermore, the two subsystem tank bodies 5 are sequentially provided with a water inlet tank 51, an intermediate tank 52 and a water level regulating tank 53, and a filler module 58 is provided in the middle part of the water inlet tank 51 and the intermediate tank 52;

A partition plate 3 54 is provided between the water inlet pool 51 and the middle pool 52, the bottom of the partition plate 3 54 is flush with the bottom of the filler module 58, a partition plate 4 56 is provided between the water level regulating pool 53 and the middle pool 52, the bottom end of the partition plate 4 56 is in contact with the bottom of the subsystem pool body 5, and a plurality of through holes are opened at the bottom of the partition plate 4 56;

Aquatic plants are planted on the filler module 58 between the partition three 54 and the partition four 56. The aquatic plants are at least one of aquatic canna, cattail, pennywort, and foxtail algae.

Two alternating drainage systems are provided between the two water level regulating tanks 53;

An overflow outlet pipe 57 is provided between the water level regulating tank 53 and the intermediate tank 52. The overflow outlet pipe 57 is composed of a straight pipe and a curved pipe. The straight pipe of the overflow outlet pipe 57 passes through the partition plate 56 and is connected to the intermediate tank 52. The overflow outlet pipe 57 is provided above the filler module 58. An extended drain pipe 7 is provided at the lower end of the water outlet direction of the water level regulating tank 53. The extended drain pipe 7 passes through the water level regulating tank 53.

The anoxic tank 3 is connected to the water inlet tank 51 through a water distribution pipe 6, and the water distribution pipe 6 is arranged above the filling module 58.

Furthermore, the main box body is an integrated structure, and an inspection well 21 and an inspection well 22 are arranged on the top of the main box body. The inspection well 21 is arranged between the sedimentation tank 2 and the anaerobic tank 3, and the inspection well 22 is arranged between the anaerobic tank 3 and the anoxic tank 4; the inspection well 21 and the inspection well 22 are arranged near the partition 1 31 and the partition 2 32, and the inspection well 21 and the inspection well 22 are both provided with top hole brickwork 23 and a manhole cover 24; the main box body, the top hole brickwork 23 and the manhole cover 24 form a closed structure.

Furthermore, the alternating drainage system is composed of a water level detection structure and a drainage structure, the water level detection structure is arranged at the upper end of the water level regulating tank 53, and the drainage structure is arranged at the lower end of the water level regulating tank 53; the water level detection structure of subsystem A is connected to the drainage structure of subsystem B, and the detection structure of subsystem B is connected to the drainage structure of subsystem A, a pool pipe 112 is arranged between the water level regulating tank 53 of subsystem A and the water level regulating tank 53 of subsystem B, the water level detection structure of subsystem A and the drainage structure of subsystem B are connected by a connecting cable 106, and the connecting cable 106 passes through the pool pipe 112, and pulleys 104 are arranged on both sides of the pool pipe 112 below the connecting cable 106; the water level detection structure includes a float 101 and a float connecting rod 102, the float is connected to one end of the float connecting rod 102, and a float connecting rod rotating shaft is arranged in the middle of the float connecting rod 102 103, the end of the float connecting rod 102 away from the float 101 is connected to the connecting cable 2 106; the drainage structure includes a balance rod 109, a balance rod rotating shaft 110, a slip ring 108, a pulley 2 105, and a water outlet pipe cover 111. The balance rod 109 is connected to the float connecting rod 102 through the connecting cable 2 106, and a balance rod rotating shaft 110 is arranged in the middle of the balance rod 109. The end of the balance rod 109 away from the connecting cable 2 106 is connected to the connecting cable 1 107, and the end of the connecting cable 107 away from the balance rod 109 is connected to the water outlet pipe cover 111. The water outlet pipe cover 111 is arranged just above the extended drainage pipe 7, and a slip ring 108 is arranged on one side of the balance rod 109 connected to the connecting cable 107; a pulley 2 105 is arranged between the upper end of the connecting cable 107 and the balance rod 109, and a pulley 3 113 is arranged between the lower end of the connecting cable 107 and the outlet pipe cover 111.

Furthermore, the extended drainage pipe 7 is composed of a curved pipe 1, a straight pipe 1 71, a curved pipe 2 and a straight pipe 2 72. The straight pipe 1 runs through one end of the water level regulating tank, and the length of the straight pipe 2 72 is 3.5-4 times the length of the straight pipe 1 71.

Furthermore, there are several packing modules 58, each packing module 58 is composed of four layers of packing from top to bottom, and the four packing layers are respectively a guami stone layer, a small round ceramsite layer, a zeolite layer, and a large round ceramsite layer from top to bottom;

Furthermore, the specifications of the packing layer are as follows: the guami stone layer is 150 mm thick and has a particle size of 5 mm; the small round expanded clay layer is 200 mm thick and has a particle size of 3 mm; the zeolite layer is 300 mm thick and has a particle size of 10 mm; the large round expanded clay layer is 200 mm thick and has a particle size of 20 mm; and the gravel layer is 350 mm thick and has a particle size of 30 mm.

Furthermore, the pH value of the sewage is 6.8-7, and the filler module 58 is a No. 1 filler module, which includes a guami stone layer, an acidic small round ceramsite layer, a zeolite layer, and an acidic large round ceramsite layer.

Furthermore, the main box body and the subsystem tank body 5 are integrally formed of glass fiber reinforced plastic material, which can better prevent sewage from seeping out and polluting groundwater.

Embodiments of the present invention

Embodiment 2 has the same structure as Embodiment 1, except that

The specifications of the packing layer are as follows: the guami stone layer is 150mm thick and the particle size is 10mm; the small round expanded clay layer is 200mm thick and the particle size is 10mm; the zeolite layer is 300mm thick and the particle size is 20mm; the large round expanded clay layer is 200mm thick and the particle size is 40mm; the gravel layer is 350mm thick and the particle size is 50mm.

The unpowered underground vertical flow wetland rural domestic sewage treatment device also includes a screen pool 1, which is connected to the sedimentation tank 2 by a pipeline. A screen plate is arranged in the screen pool 1, and grilles are evenly arranged on the screen plate. A top plate 14 is arranged on the top of the screen pool 1 to completely cover the screen pool 1. A sewage interception pipe is arranged at the water inlet of the screen pool 1, and an outlet water collection tank 8 is arranged below the overflow outlet pipe 57 and the extended drain pipe 7.

A concrete cushion layer 11 is provided at the bottom of the mesh pool 1, a concrete cushion layer 2 12 is provided at the bottom of the main box body and the composite vertical flow wetland system, and a concrete cushion layer 3 13 is provided on the side of the water level regulating tank 53 connected to the extended drainage pipe 7. The height of the bottom of the mesh pool 1 is set higher than the bottom of the main box body and the subsystem pool body 5.

Concrete cushion layer 1 11, concrete cushion layer 2 12 and the bottom of the main box body and the bottom of the subsystem pool body 5 are filled with medium-coarse sand, and the gap between the side of the main box body opposite to the subsystem pool body 5 and the side gap between concrete cushion layer 3 13 and the subsystem pool body 5 are filled with plain soil.

Through the design of the concrete cushion layer 1 1 , the concrete cushion layer 2 12 and the concrete cushion layer 3 13 , the device can be buried in the ground more stably and firmly.

Furthermore, lawn is planted on the soil surface above the main box.

Furthermore, the unpowered buried vertical flow wetland rural domestic sewage treatment device also includes a sewage collection device, which includes a sewage collection pipe and a sewage collection well connected to farmers. The sewage collection device is connected to a sewage interception pipe provided at the water inlet of the grid pool. The collected farmers' sewage includes black water and gray water of the farmers. Black water refers to the effluent from the farmers' septic tanks, and gray water refers to the sewage discharged from the farmers' daily life.

Embodiment 3 is different from Embodiment 2 in that the pH value of the sewage is 8.7-9, and the filler module 58 is a No. 2 filler module, which is a guami stone layer, an alkaline small round ceramsite layer, a zeolite layer, and an alkaline large round ceramsite layer.

Embodiment 4, referring to FIG. 6 , the unpowered underground vertical flow wetland rural domestic sewage treatment device of the above-mentioned embodiment 2 is used to treat sewage, and the specific steps include:

The present invention also discloses a method for treating rural domestic sewage in an unpowered underground vertical flow wetland, which uses the above-mentioned unpowered underground vertical flow wetland rural domestic sewage treatment device for treatment, and the steps include:

S2. The sewage collection device collects sewage: collects domestic sewage and/or gray water overflowing from septic tanks of each household and enters the grid pool 1 for treatment;

S3. Sedimentation tank sedimentation: The sewage collected in step S2 is precipitated in sedimentation tank 2, which adopts a vertical sedimentation tank with a hydraulic retention time of 2h to remove the remaining suspended organic matter in the domestic sewage;

S4. Anaerobic tank treatment: The treated sewage in step S3 flows into the anaerobic tank 3, and the anaerobic biofilm is used to remove the organic pollutants in the colloid and dissolved state in the sewage. The filler is suspended by the hanger provided in the anaerobic tank 3, and a soft filler or a semi-soft filler is used to provide a solid surface for the attachment and growth of anaerobic microorganisms, so that a biofilm is formed on the surface of the filler;

S5. Anoxic tank treatment: The sewage after anaerobic treatment in step S4 is passed into the anoxic tank 4 for anoxic treatment;

S6. Composite vertical flow wetland system treatment: The sewage treated in the anoxic pool 4 is discharged to the inlet pool 51 of the composite vertical flow wetland system through the water distribution pipe 6. The sewage is treated by the filler module 58 and the gravel layer 55 in the composite vertical flow wetland system and infiltrates to the bottom of the wetland. The water discharged from the composite vertical flow wetland system meets the first-level standard in Guangdong Province's Rural Domestic Sewage Treatment Discharge Standard DB44/2208‑2019;

S7. Resource utilization of tail water: The tail water treated and purified in step S6 is discharged to the effluent collection pool 8 through the extended drainage pipe 7, and the excess purified tail water flows out to the effluent collection pool 8 through the overflow outlet pipe 57. The water collected in the effluent collection pool 8 can be used for agricultural irrigation.

Industrial Applicability

After the above treatment, the water index reaches the following levels:

(1) Transparency>25cm;

(2) Dissolved oxygen>2 mg/L;

(3) Redox potential>50mV;

(4) Ammonia nitrogen <2 mg/L;

(5) BOD: <10 mg/L;

(6) COD: <40 mg/L;

(7) Total phosphorus: <0.4 mg/L;

(8) Permanganate index: <15mg/L.

The above description is only a preferred example of the present invention and is not any formal or substantial limitation to the present invention. All technical solutions under the concept of the present invention belong to the protection scope of the present invention. Any equivalent changes and modifications made to the above examples based on the essential technology of the present invention should also be regarded as the protection scope of the present invention.

Claims

A non-powered underground vertical flow wetland rural domestic sewage treatment device, characterized in that it comprises a main box and a composite vertical flow wetland system, wherein the main box is composed of a sedimentation tank (2), an anaerobic tank (3), and an anoxic tank (4) which are connected in sequence;

The main box body is provided with a partition plate 1 (31) and a partition plate 2 (32) to separate the main box body into a sedimentation tank (2), an anaerobic tank (3), and an anoxic tank (4); the sedimentation tank (2) and the anaerobic tank (3) are connected via an opening 1 provided at the upper end of the partition plate 1 (31); the anaerobic tank (3) and the anoxic tank (4) are connected via an opening 2 provided at the bottom of the partition plate 2 (32); and pipes are provided at both the opening 1 and the opening 2;

The anaerobic tank (3) is provided with a plurality of filler racks (33) and a plurality of baffle plates 1 (34) and a plurality of baffle plates 2 (35). The baffle plates 1 (34) are bent along the sewage flow direction near the bottom of the anaerobic tank (3) and have a gap between them and the bottom of the anaerobic tank (3). The baffle plates 2 (35) are vertically arranged on the bottom of the anaerobic tank (3) and in contact with the bottom of the anaerobic tank (3). The height of the baffle plates 1 (34) is higher than the opening 1, and the height of the baffle plates 2 (35) is lower than the opening 1. The filler rack (33) is arranged between the baffle plates 1 (34) and the baffle plates 2 (35).

A soft filler group (36) is provided;

The composite vertical flow wetland system is composed of two parallel subsystems A and B. The subsystems A and B both include a subsystem pool body (5). Each of the subsystem pool bodies (5) is provided with five layers of filler matrix filter material layers. The upper four layers of the filler matrix filter material layers are modularly designed. A plurality of square stainless steel mesh boxes are used to load the four layers of filler. Each stainless steel mesh box is a filler module (58). The bottom of the filler module (58) is a gravel layer (55).

The two subsystem tank bodies (5) are each provided with a water inlet tank (51), an intermediate tank (52) and a water level regulating tank (53) in sequence, and the filler module (58) is provided in the middle part of the water inlet tank (51) and the intermediate tank (52);

A partition plate three (54) is provided between the water inlet pool (51) and the intermediate pool (52), the bottom of the partition plate three (54) being flush with the bottom of the filler module (58), a partition plate four (56) is provided between the water level regulating pool (53) and the intermediate pool (52), the bottom end of the partition plate four (56) being in contact with the bottom of the subsystem pool body (5), and a plurality of through holes being provided at the bottom of the partition plate four (56);

Aquatic plants are planted on the filler module (58) between the partition three (54) and the partition four (56);

Two alternating drainage systems are arranged between the two water level regulating pools (53);

An overflow outlet pipe (57) is provided between the water level regulating pool (53) and the intermediate pool (52); the overflow outlet pipe (57) is composed of a straight pipe and a curved pipe; the straight pipe of the overflow outlet pipe (57) passes through the partition plate 4 (56) to communicate with the intermediate pool (52), and is provided above the filler module (58); an extended drainage pipe (7) is provided at the lower end of the water level regulating pool (53) in the water outlet direction; the extended drainage pipe (7) passes through the water level regulating pool (53);

The anoxic pool (3) is connected to the water inlet pool (51) via a water distribution pipe (6), and the water distribution pipe (6) is arranged above the filler module (58);

The alternating drainage system is composed of a water level detection structure and a drainage structure, wherein the water level detection structure is arranged at the upper end of the water level regulating pool (53), and the drainage structure is arranged at the lower end of the water level regulating pool (53); a pool connecting pipe (112) is arranged between the water level regulating pool (53) of the A subsystem and the water level regulating pool (53) of the B subsystem, and the water level detection structure of the A subsystem is connected to the drainage structure of the B subsystem via a second connecting cable (106). The second connecting cable (106) passes through the pool pipe (112), and pulleys (104) are arranged on both sides of the pool pipe (112) below the second connecting cable (106); the water level detection structure comprises a float (101) and a float connecting rod (102), the float is connected to one end of the float connecting rod (102), a float connecting rod rotating shaft (103) is arranged in the middle of the float connecting rod (102), and the end of the float connecting rod (102) away from the float (101) is connected to the second connecting cable (101). 6); the drainage structure comprises a balance rod (109), a balance rod rotating shaft (110), a slip ring (108), a second pulley (105), and a water outlet pipe cover (111); the balance rod (109) is connected to the float connecting rod (102) via a second connecting cable (106); a balance rod rotating shaft (110) is arranged in the middle of the balance rod (109); an end of the balance rod (109) away from the second connecting cable (106) is connected to a first connecting cable (107); the first connecting cable (107) One end away from the balance bar (109) is connected to a water outlet pipe cover (111), and the water outlet pipe cover (111) is arranged just above the extended drainage pipe (7). A slip ring (108) is arranged on one side of the balance bar (109) connected to the connecting cable 1 (107); a pulley 2 (105) is arranged between the upper end of the connecting cable 1 (107) and the balance bar (109), and a pulley 3 (113) is arranged between the lower end of the connecting cable 1 (107) and the top of the water outlet pipe cover (111).
The non-powered underground vertical flow wetland rural domestic sewage treatment device according to claim 1 is characterized in that: the main box body is an integrated structure, and an inspection well 1 (21) and an inspection well 2 (22) are arranged on the top of the main box body, the inspection well 1 (21) is arranged between the sedimentation tank (2) and the anaerobic tank (3), and the inspection well 2 (22) is arranged between the anaerobic tank (3) and the anoxic tank (4); the inspection well 1 (21) and the inspection well 2 (22) are both provided with top hole brickwork (23) and a well cover (24); the main box body, the top hole brickwork (23) and the well cover (24) form a closed structure.
The non-powered underground vertical flow wetland rural domestic sewage treatment device according to claim 1 is characterized in that: there are a plurality of filler modules (58), each of which is composed of four layers of fillers from top to bottom, and the four layers of fillers are, from top to bottom, a guami stone layer, a small round ceramsite layer, a zeolite layer, and a large round ceramsite layer.
The non-powered underground vertical flow wetland rural domestic sewage treatment device according to claim 3 is characterized in that the filler module (58) is a No. 1 filler module, and the No. 1 filler module is a guami stone layer, an acidic small round ceramsite layer, a zeolite layer, and an acidic large round ceramsite layer.
The non-powered underground vertical flow wetland rural domestic sewage treatment device according to claim 3 is characterized in that the filler module (58) is a No. 2 filler module, and the No. 2 filler module is a guami stone layer, an alkaline small round ceramsite layer, a zeolite layer, and an alkaline large round ceramsite layer.
The unpowered underground vertical flow wetland rural domestic sewage treatment device according to claim 3 is characterized in that it also includes a screen pool (1), the screen pool (1) is connected to the sedimentation tank (2) by a pipeline, a screen plate is arranged in the screen pool (1), grilles are evenly arranged on the screen plate, a top plate (14) is arranged on the top of the screen pool (1), a sewage interception pipe is arranged at the water inlet of the screen pool (1), and an outlet water collection pool is arranged below the overflow outlet pipe (57) and the extended drainage pipe (7).
The non-powered underground vertical flow wetland rural domestic sewage treatment device according to claim 6 is characterized in that: the main box body and the subsystem pool body (5) are integrally formed of glass fiber reinforced plastic material; a concrete cushion layer 1 (11) is provided at the bottom of the mesh pool (1), a concrete cushion layer 2 (12) is provided at the bottom of the main box body and the composite vertical flow wetland system, a concrete cushion layer 3 (13) is provided on the side of the water level regulating pool (53) connected to the extended drainage pipe (7), and the height of the bottom of the mesh pool (1) is higher than the bottom of the main box body and the subsystem pool body (5).