CN103288215A - Anti-seepage constructed wetland system - Google Patents

Abstract

The invention provides an anti-seepage artificial wetland system which comprises an artificial wetland pool, wherein the bottom and the periphery of the artificial wetland pool are provided with anti-seepage layers, the artificial wetland pool is sequentially provided with a planting layer, a gravel layer, a composite filler layer and a drain pipe, wherein wetland plants are planted in the planting layer, the planting layer is used for primarily purifying sewage, the gravel layer is used for secondarily purifying the sewage, the composite filler layer is used for secondarily purifying the sewage, and the drain pipe is arranged from top to bottom, and the anti-seepage layers are made of 0.06-0.07 part of water-soluble silicon dioxide, 0.08-0.1 part of potassium methyl silicate, 0.4-0.5 part of potassium silicate, 260-1800 parts of river sand and 70-220 parts of water. The sewage is purified in a triple mode through the planting layer, the gravel layer and the composite packing layer, and the purification efficiency is improved; the anti-seepage layer made of different formulas is selected, so that the anti-aging and high and low temperature resistance of the anti-seepage layer of the artificial wetland is greatly improved, and the anti-seepage capability of the artificial wetland system is improved.

Description

An anti-seepage constructed wetland system

technical field

The invention relates to the fields of artificial wetland construction and water and soil conservation, in particular to an anti-seepage artificial wetland system, especially suitable for vertical flow artificial wetland systems. the

Background technique

The study of constructed wetlands originated in the 1970s and was derived from the study of wetlands. Constructed wetland is a ground similar to swampland that is artificially constructed and operated under control. Sewage and sludge are distributed to the artificially constructed wetland in a controlled manner. When sewage and sludge flow in a certain direction, they are mainly used It is a technology for treating sewage and sludge through the triple synergy of physics, chemistry and biology of soil, artificial medium, plants and microorganisms. Its mechanism of action includes adsorption, retention, filtration, redox, precipitation, microbial decomposition, transformation, plant shading, residue accumulation, transpiration of water and nutrient absorption, and the action of various animals. Due to the characteristics of low investment, low energy consumption, large buffer capacity, and simple process, constructed wetlands have been widely used for domestic sewage, storm runoff, rural non-point source pollution and lake pollution prevention and control. the

Constructed wetlands mainly include horizontal flow constructed wetlands and vertical flow constructed wetlands. The horizontal flow constructed wetland is to make the sewage flow through the sand, medium, and plant roots in the process of flowing horizontally from the water inlet to the water outlet to achieve the purpose of purification. The water level of the horizontal flow artificial wetland is relatively shallow, and its operation is greatly affected by natural climate conditions, which are prone to mosquitoes and flies, and have peculiar smell. In the vertical flow constructed wetland system, the sewage flows vertically from the surface to the bottom of the bed, and in the process of vertical flow, the sewage passes through different medium layers successively to achieve the purpose of purification. Compared with horizontal flow constructed wetlands, vertical flow constructed wetlands have the advantages of small footprint, high treatment efficiency, and no odor due to their unique construction structure and water flow pattern, and have gradually become the mainstream of constructed wetland systems. the

Due to the deep water level and strong pressure generated by the vertical flow artificial system, higher requirements are put forward for the anti-seepage technology of the constructed wetland pool. At present, the anti-seepage materials installed on the bottom and side walls of the constructed wetland pool have the disadvantages of easy aging, great influence of high and low temperature, and high price, which greatly reduces the efficiency of sewage treatment in the constructed wetland. In addition, due to its vertical structure, the vertical flow artificial wetland makes the oxygen supply in the wetland insufficient, and the whole system is placed in a relatively single anaerobic environment, which inhibits the nitrification reaction in the top aerobic zone and reduces the nitrogen removal rate; in order to improve the wetland For the internal oxygen supply effect, the current artificial wetland generally adopts the method of increasing oxygen by bottom aeration, but the bottom of the vertical flow constructed wetland is an anaerobic area, and the bottom aeration method will make the anaerobic area at the bottom of the constructed wetland too small, which will affect the oxygen in the system. denitrification reaction. the

Contents of the invention

The purpose of the present invention is to overcome the deficiencies in the prior art and provide an anti-seepage artificial wetland system with high sewage treatment efficiency. the

The purpose of the present invention is achieved by the following technical solutions:

An anti-seepage constructed wetland system, including a constructed wetland pool with anti-seepage layers on the bottom and surroundings, the constructed wetland pool is sequentially provided with planting layers planted with wetland plants and used for primary purification of sewage. For the gravel layer for secondary purification of sewage, the composite packing layer for secondary purification of sewage, and the drainage pipe, the anti-seepage layer is made of the following mass parts:

Water-soluble silica, 0.06-0.07 parts;

Potassium methyl silicate, 0.08-0.1 part;

Potassium silicate, 0.4-0.5 parts;

River sand, 260-1800 parts;

And water, 70～220 parts. the

The constituent materials of the anti-seepage layer have the following characteristics:

Water-soluble silica, chemically inert, used as anti-caking agent;

Potassium methyl silicate, which is permeable, absorbable, and able to maintain the natural appearance of the substrate, can react with CO2 or other acidic compounds in the air to form an insoluble mesh waterproof and breathable film on the surface of the substrate , has excellent waterproof effect and anti-seepage, moisture-proof, anti-rust, anti-aging, anti-pollution and other advantages, avoiding moisture absorption into the substrate, thereby reducing peeling caused by freeze-thawing and weathering, and increasing the life of the substrate; 

Potassium silicate, used to improve the temperature resistance of the surface of the anti-seepage layer and prevent crystallization of the surface of the anti-seepage layer;

River sand, which plays a skeleton or filling role in the anti-seepage layer;

In the above scheme, the anti-seepage layer made of water-soluble silica, potassium methyl silicate, potassium silicate, river sand and water has greatly improved the aging resistance and high and low temperature resistance of the anti-seepage layer, thereby improving the anti-seepage performance. In addition, the materials used to prepare the anti-seepage layer are all common materials, which are easy to obtain and cheap. the

The shape of the constructed wetland pool can be any regular figure, preferably rectangular; specifically, the aspect ratio of the rectangular constructed wetland pool is 5:1-10:1, and the depth is 100cm-140cm. the

The planting layer is covered with sludge to facilitate the growth and attachment of wetland plants. As a preferred technical solution, the thickness of the sludge is 20cm to 30cm; the wetland plants planted on the planting layer can be aquatic plants that are convenient for growing in a wetland environment. Such as reed, canna, calamus, etc., can also be emergent plants with high survival rate, well-developed root system, and long growth cycle, such as water hyacinth and water onion. the

The gravel layer blocks large particles of impurities through filtration, and uses the combined action of physical, chemical and biochemical reactions of microorganisms on the surface to remove the filtered large particles of impurities to perform secondary purification of sewage. the

The composite packing layer is used to purify the sewage after the gravel layer is purified; the inventor has found through long-term research that the composite packing layer has a porosity ≥ 30%, a bulk density of 1200-1500Kg/m ³ , and a water permeability of 15 Under the condition of ~20m/h, the purification effect on sewage is the best. in:

Porosity refers to the ratio of the void volume between particles to the total volume in the bulk volume of granular materials;

Bulk density means the apparent density including all pores in the volume of the material;

The water permeability rate refers to the flow rate of water in the internal structure of the filter material. the

In order to improve the purification effect of the composite material layer, as a further technical solution for improvement, the composite filler layer is made of substances with the following mass ratios:

Limestone with a particle size of 2-8mm, 10-20%;

Cinder with a particle size of 3-10mm, 20-30%;

Fly ash with particle size less than 2mm, 5-10%;

Clay with particle size less than 2mm, 15-20%;

Volcanic rock with a particle size of 3-8mm, 5-20%;

Modified diatomite with a particle size of 2-8mm, 5-10%;

and water, 5-10%. the

As a further improved technical solution, the anti-seepage constructed wetland system also includes an air supply device, the air supply pipe of the air supply device is inserted in the middle and upper part of the constructed wetland pool and is located in the gravel layer, and the upper surface of the air supply pipe A plurality of air supply holes are evenly arranged, and the air supply holes are covered with a matching protective sheet, and the protective sheet is movably connected with the air supply pipe, so that the protective sheet is lifted when the air is supplied, and resets when the air is not supplied. the

As a further improved technical solution, the air supply device also includes an air compressor connected to the air supply pipe, and the air supply pipe is covered with a protective hard air-permeable mesh pipe, in order to prevent the filler in the gravel layer from penetrating the air-permeable mesh pipe The air supply pipe is damaged, and the mesh diameter of the breathable mesh pipe is smaller than the particle diameter of the gravel layer filler where it is located. the

Compared with the prior art, the present invention has the following advantages and beneficial effects:

(1) The present invention performs triple purification of sewage through the planting layer, gravel layer and composite packing layer, which improves the purification efficiency, and the structure and preparation components of the composite packing layer further improve the purification efficiency of the constructed wetland of the present invention;

(2) The present invention greatly improves the anti-seepage performance of the artificial wetland anti-seepage layer by selecting the anti-seepage layer made of different formulas, thereby improving the anti-seepage ability; at the same time, the materials used to prepare the anti-seepage layer are common Substances are easily available and cheap;

(3) The present invention promotes the nitrification reaction in the aerobic zone at the top of the constructed wetland pool and the reaction in the anaerobic zone at the bottom of the constructed wetland pool by setting an air supply pipe in the middle and upper part of the constructed wetland pool, and the air supply holes are arranged on the upper surface of the air supply pipe. Nitrification reaction, thereby improving the purification capacity of constructed wetlands;

(4) In the present invention, by covering the air supply hole with a matching protective sheet, the protective sheet is movably connected with the air supply pipe, so that the protective sheet is lifted when the air is supplied and reset when the air is not supplied. This structure prevents the air supply hole from being polluted by sewage. Impurities block the air supply pipe to prevent normal air supply;

(5) The present invention improves the protection of the air supply pipe by installing a hard breathable mesh pipe outside the air supply pipe, and the mesh diameter of the breathable mesh pipe is smaller than the particle size of the gravel layer filler;

(6) The anti-seepage constructed wetland system provided by the present invention has a simple structure and is easy to realize. the

Description of drawings

Fig. 1 is a schematic diagram of the structure of the anti-seepage constructed wetland system of the present invention. the

Detailed ways

The present invention will be further described in detail below with reference to the embodiments and the accompanying drawings, but the embodiments of the present invention are not limited thereto. the

As shown in Figure 1, an anti-seepage constructed wetland system provided by the present invention includes a rectangular constructed wetland pool provided with an anti-seepage layer 5 at the bottom and surroundings, and the constructed wetland pool is sequentially arranged with wetland plants from top to bottom for Planting layer 1 for primary purification of sewage, gravel layer 2 for secondary purification of sewage, composite packing layer 3 for secondary purification of sewage, and drainage pipe 4; the anti-seepage constructed wetland system also includes a gas supply The air supply device includes an air supply pipe 6, an air compressor 8 connected to the air supply pipe 6, and a hard breathable mesh pipe 7 covered on the air supply pipe 6. The air supply pipe 6 is inserted horizontally in the middle and upper part of the constructed wetland pool and is located in the gravel layer. In 2, the upper surface of the air supply pipe 2 is uniformly provided with a plurality of air supply holes, and the air supply holes are covered with a matching protective sheet. The protective sheet is movably connected with the air supply pipe, so that the protective sheet is lifted when the air is supplied, and when it is not supplied. Reset, the mesh diameter of the air-permeable mesh pipe 7 is smaller than the particle diameter of the filler in the gravel layer 2 . the

in:

The anti-seepage layer material is made by the following methods:

(1) Mix 0.06-0.07 parts of water-soluble silicon dioxide, 0.08-0.1 parts of potassium methyl silicate, 0.4-0.5 parts of potassium silicate and 0.6 parts of water to make a hydrophobic agent;

(2) Prepare the hydrophobic agent prepared in (1) and water according to the mass ratio of 1:70 to 1:220 to make a hydrophobic solution;

(3) Mix the hydrophobic solution and the river sand according to the mass ratio of 1:5 to 1:8 to obtain a mixture;

(4) Drying the mixture to obtain the anti-seepage layer material. the

The filler of the composite filler layer is made by the following methods:

First, limestone with a particle size of 2-8mm and a mass ratio of 10-20%, cinder with a particle size of 3-10mm and a mass ratio of 20-30%, and cinders with a particle size of less than 2mm and a mass ratio of 5-10% Fly ash, clay with a particle size of less than 2mm and a mass ratio of 15-20%, volcanic rock with a particle size of 3-8mm and a mass ratio of 5-20%, a particle size of 2-8mm and a mass ratio of 5-10% The modified diatomite, and water with a mass ratio of 5-10% are mixed and stirred evenly;

Secondly, the uniformly stirred slurry is introduced into the mold, and pressed under the pressure of 80-120Pa/mm2, and then air-dried naturally after demoulding, and finally the filler required for the composite filler layer is obtained. the

Concrete operation principle of the present invention is:

(1) After the sewage is injected into the constructed wetland pool, it first passes through the planting layer, and the planting layer removes some pollutants through the plant root system;

(2) The sewage that has been preliminarily purified by the planting layer flows to the gravel layer. The gravel layer blocks and detours the large-particle impurities through filtration, and uses the combined action of the physical, chemical and biochemical reactions of microorganisms on its surface to remove the filtered large-particle impurities. Secondary purification of sewage;

(3) The sewage purified by the gravel layer will enter the composite packing layer for further purification, and the innovation of the structure and preparation components of the composite packing layer enables it to have high purification capacity and thoroughly purify the sewage;

(4) The sewage thoroughly purified by the composite packing layer is finally discharged by the drain pipe. the

During operation, the air supply pipe of the gravel layer only supplies oxygen to the upper end of the constructed wetland pool through the air supply holes on its upper surface, which promotes the nitrification reaction in the itchy area at the upper end of the constructed wetland pool and the reaction in the anaerobic area at the lower end of the constructed wetland pool. The nitrification reaction improves the purification ability of the constructed wetland. the

Material effect experiment of anti-seepage layer:

Example 1:

According to the preparation method of the above-mentioned anti-seepage layer materials, the composition materials of the anti-seepage layer are proportioned according to the following parts by mass:

Water-soluble silicon dioxide, 0.06 parts;

Potassium methyl silicate, 0.08 parts;

Potassium silicate, 0.4 parts;

River sand, 260 parts;

and water, 70 parts. the

The prepared anti-seepage layer material was subjected to the following experiments. the

Experiment 1:

First, prepare a glass container, using the shape of the glass container to simulate the artificial wetland pool. The shape of the glass container is rectangular, the depth is 150cm, and there is a leak at the bottom of the container; secondly, spread the anti-seepage layer material prepared according to the above method on the container At the bottom of the bottom, make the anti-seepage layer material completely cover the spout, and the thickness of the anti-seepage layer material is 2-4cm; then, inject 140cm of waste liquid that usually needs to be treated in the constructed wetland pool into the glass container; finally, leak water at the bottom of the container Place a piece of dry filter paper at the lower end of the mouth, and observe the water seepage of the glass container within 24 hours;

Result: By observation, within 24 hours of adding water to the container, the filter paper at the bottom of the container was dry and no waste water seeped out. This result shows that the anti-seepage layer of the present invention can meet the anti-seepage requirements for high-level waste liquid. the

Experiment 2:

The difference from Experiment 1 is that 140 cm of waste liquid at a temperature of 40 degrees Celsius was injected into the glass container, and the observations were made in the first week, the second week, the third week, the fourth week, the second month, and the third month. The seepage status of the water leakage at the bottom of the container and make statistics. the

Results: By observation, during the statistical period, the filter paper at the bottom of the container was dry and no waste water seeped out. This result shows that the anti-seepage layer of the present invention has good effects of high temperature resistance and aging resistance. the

Example 2:

According to the preparation method of the above-mentioned anti-seepage layer materials, the composition materials of the anti-seepage layer are proportioned according to the following parts by mass:

Water-soluble silicon dioxide, 0.065 parts;

Potassium methyl silicate, 0.09 parts;

Potassium silicate, 0.45 parts;

River sand, 1030 parts;

and water, 135 parts. the

The prepared anti-seepage layer material was subjected to the following experiments. the

Experiment 1:

First, prepare a glass container, using the shape of the glass container to simulate the artificial wetland pool. The shape of the glass container is rectangular, the depth is 150cm, and there is a leak at the bottom of the container; secondly, spread the anti-seepage layer material prepared according to the above method on the container At the bottom of the bottom, make the anti-seepage layer material completely cover the spout, and the thickness of the anti-seepage layer material is 2-4cm; then, inject 140cm of waste liquid that usually needs to be treated in the constructed wetland pool into the glass container; finally, leak water at the bottom of the container Place a piece of dry filter paper at the lower end of the mouth, and observe the water seepage of the glass container within 24 hours;

Result: By observation, within 24 hours of adding water to the container, the filter paper at the bottom of the container was dry and no waste water seeped out. This result shows that the anti-seepage layer of the present invention can meet the anti-seepage requirements for high-level waste liquid. the

Experiment 2:

The difference from Experiment 1 is that 140 cm of waste liquid at a temperature of 40 degrees Celsius was injected into the glass container, and the observations were made in the first week, the second week, the third week, the fourth week, the second month, and the third month. The seepage status of the water leakage at the bottom of the container and make statistics. the

Results: By observation, during the statistical period, the filter paper at the bottom of the container was dry and no waste water seeped out. This result shows that the anti-seepage layer of the present invention has good effects of high temperature resistance and aging resistance. the

Example 3:

According to the preparation method of the above-mentioned anti-seepage layer materials, the composition materials of the anti-seepage layer are proportioned according to the following parts by mass:

Water-soluble silicon dioxide, 0.07 parts;

Potassium methyl silicate, 0.1 part;

Potassium silicate, 0.5 parts;

River sand, 1800 parts;

and water, 200 parts. the

The prepared anti-seepage layer material was subjected to the following experiments. the

Experiment 1:

First, prepare a glass container, using the shape of the glass container to simulate the artificial wetland pool. The shape of the glass container is rectangular, the depth is 150cm, and there is a leak at the bottom of the container; secondly, spread the anti-seepage layer material prepared according to the above method on the container At the bottom of the bottom, make the anti-seepage layer material completely cover the spout, and the thickness of the anti-seepage layer material is 2-4cm; then, inject 140cm of waste liquid that usually needs to be treated in the constructed wetland pool into the glass container; finally, leak water at the bottom of the container Place a piece of dry filter paper at the lower end of the mouth, and observe the water seepage of the glass container within 24 hours;

Result: By observation, within 24 hours of adding water to the container, the filter paper at the bottom of the container was dry and no waste water seeped out. This result shows that the anti-seepage layer of the present invention can meet the anti-seepage requirements for high-level waste liquid. the

Experiment 2:

The difference from Experiment 1 is that 140 cm of waste liquid at a temperature of 40 degrees Celsius was injected into the glass container, and the observations were made in the first week, the second week, the third week, the fourth week, the second month, and the third month. The seepage status of the water leakage at the bottom of the container and make statistics. the

Results: By observation, during the statistical period, the filter paper at the bottom of the container was dry and no waste water seeped out. This result shows that the anti-seepage layer of the present invention has good effects of high temperature resistance and aging resistance. the

The above-mentioned embodiments only express the implementation manner of the present invention, and the description thereof is relatively specific and detailed, but should not be construed as limiting the patent scope of the present invention. It should be noted that, for those skilled in the art, several modifications and improvements can be made without departing from the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent for the present invention should be based on the appended claims. the

Claims (7)

1. antiseepage artificial wet land system, comprise bottom and the artificial swamp pond that is provided with impervious barrier all around, it is characterized in that: described artificial swamp pond from top to bottom set gradually plant wetland plant and be used for to sewage carry out primary purification the plantation layer, be used for to sewage carry out secondary-cleaned gravel bed, be used for compounded mix layer and water shoot that sewage is purified again, described impervious barrier is made by following materials in parts by mass:

Water-soluble silicon-dioxide, 0.06～0.07 part;

Methyl siliconic acid potassium, 0.08～0.1 part;

Potassium silicate, 0.4～0.5 part;

River sand, 260 parts～1800 parts;

And water, 70～220 parts.

2. antiseepage artificial wet land system according to claim 1, it is characterized in that: described artificial swamp pond is rectangle, and the long-width ratio in described rectangle artificial swamp pond is 5:1～10:1, and the degree of depth is 100cm～140cm.

3. antiseepage artificial wet land system according to claim 1 is characterized in that: be coated with mud on the described plantation layer, the thickness of described mud is 20cm～30cm.

4. antiseepage artificial wet land system according to claim 1, it is characterized in that: described compounded mix layer is made by the material of following mass ratio:

Particle diameter is the Wingdale of 2～8mm, 10%-20%;

Particle diameter is the cinder of 3～10mm, 20%-30%;

Particle diameter is less than the flyash of 2mm, 5%-10%;

Particle diameter is less than the clay of 2mm, 15%-20%;

Particle diameter is 3～8mm volcanics, 5%-20%;

Particle diameter is 2～8mm modification infusorial earth, 5%-10%;

And water, 5%-10%.

5. antiseepage artificial wet land system according to claim 4, it is characterized in that: the porosity of described compounded mix layer 〉=30%, volume density are 1200～1500Kg/m ³, permeation rate is 15～20m/h.

6. antiseepage artificial wet land system according to claim 1; it is characterized in that: described antiseepage artificial wet land system also comprises an air feeder; the air-supply duct of air feeder is horizontal to be inserted in the middle and upper part in described artificial swamp pond and is positioned at gravel bed; the upper surface of described air-supply duct evenly is provided with a plurality of air vents; air vent is coated with the screening glass of coupling; described screening glass and air-supply duct are started screening glass for flexibly connecting when air feed, reset when air feed not.

7. antiseepage artificial wet land system according to claim 6; it is characterized in that: described air feeder also comprises the air compressor that is connected with air-supply duct; described air-supply duct is with the ventilative webmaster of hard of protectiveness outward, and the grid diameter of described ventilative webmaster is less than the particle diameter of gravel bed filler of living in.

Images