CN-121974496-A - Construction and application of novel light-driven ecological wetland system device

CN121974496ACN 121974496 ACN121974496 ACN 121974496ACN-121974496-A

Abstract

The invention relates to the technical field of environmental engineering and constructed wetland, and discloses construction and application of a novel light-driven ecological wetland system device, which comprises a light-driven ecological wetland system and a light-driven ecological wetland device, wherein the system is operated cooperatively based on an electrochemical workstation and a vertical subsurface flow constructed wetland system, and comprises a vertical subsurface flow constructed wetland system, which consists of a water inlet unit, a vegetation root system treatment unit, a water outlet unit and a matrix filled in the water inlet unit, a vegetation root system treatment unit and a water outlet unit; the optical driving ecological wetland device comprises a soil layer body, wherein an adsorption layer is paved at the bottom of the soil layer body, and a gravel layer is paved at the bottom of the adsorption layer. According to the invention, by replacing the matrix of the wetland system, the iron tailings can participate in the construction of the wetland system, the adsorption and degradation effects are exerted, the vertical subsurface flow adsorption effect is enhanced, and the photocatalytic hematite-lactic acid bacteria can introduce a solar light driven microbial fuel cell system into the wetland system on the surface layer, so that the effective removal of heavy metal pollution is realized.

Inventors

WANG LEI
REN GUIPING
QIN RUNJIE
ZHANG YONGAN
WANG JINGBO
TONG YUNLONG
QIN HAIJUAN

Assignees

甘肃省有色工程勘察设计研究院
兰州大学

Dates

Publication Date: 20260505
Application Date: 20260206

Claims (10)

1. The novel light-driven ecological wetland system device comprises a light-driven ecological wetland system and a device, and is characterized in that the system is operated cooperatively based on an electrochemical workstation and a vertical subsurface flow constructed wetland system, and comprises the vertical subsurface flow constructed wetland system, a water inlet unit, a vegetation root system treatment unit, a water outlet unit and a matrix filled in the vertical subsurface flow constructed wetland system; The light-driven ecological wetland device comprises a soil layer body (2), wherein an adsorption layer (3) is paved at the bottom of the soil layer body (2), a gravel layer (4) is paved at the bottom of the adsorption layer (3), and a vertical diameter outflow water area (5) is arranged at the bottom of the gravel layer (4); the soil layer body (2) is paved with a soil layer surface (8), the plant body (1) is planted in the soil layer surface (8) in a penetrating manner, and an LED light source (9) for light driving is arranged at the top of the soil layer surface (8); the inside of the soil layer body (2) is fixedly provided with a small hole (6) for testing electrochemical activity.
2. The novel light-driven ecological wetland system device according to claim 1, wherein the bottom of the soil layer body (2) is fixedly provided with a partition plate (7), and the partition plate (7) is made of stainless steel.
3. The novel light-driven ecological wetland system device according to claim 2, wherein the thickness of the partition plate (7) is 15cm, and a plurality of 1.5cm small holes are formed through the inside of the partition plate (7).
4. The novel light-driven ecological wetland system device according to claim 1, wherein the number of the test electrochemical activity small holes (6) is two, and the diameter of the test electrochemical activity small holes (6) is 1.5cm.
5. The novel light-driven ecological wetland system device according to claim 1, wherein loess from Gansu province is placed on the upper part of the adsorption layer (3), and the height of the soil layer (3) is 20 cm.
6. A novel light-driven ecological wetland system device according to claim 1, wherein the upper part of said gravel layer (4) is provided with a bottom plate, and the thickness of said gravel layer (4) is 5 cm.
7. The novel light-driven ecological wetland system device according to claim 6, wherein biochar, vermiculite and iron tailing adsorption materials are paved on the upper part of the bottom plate, and the thickness of the adsorption layer is 5 cm.
8. A novel light-driven ecological wetland system device according to claim 1, characterized in that said plant body (1) selects calamus as a plant treatment unit.
9. A method for constructing a novel light-driven ecological wetland system device, which is based on the novel light-driven ecological wetland system device according to any one of claims 1 to 8, and is characterized by comprising the following steps: step one, placing a designed external device frame on a stable plane, wherein the device is cylindrical, the height is 50 cm, and the inner diameter is 15 cm; step two, arranging a bottom plate with the diameter of 15 cm at the position 5cm away from the bottom of the device, paving gravels at the bottom, wherein the thickness of a gravel layer (4) is 5 cm; Placing the same bottom plate on the upper part of the gravel layer (4), and paving adsorption materials of biochar, vermiculite and iron tailings on the upper part of the bottom plate, wherein the thickness of the adsorption layer (3) is 5 cm; fourthly, modifying the adsorption material in an H 2 SO 4 solution with the pH value of=2; fifthly, placing loess from Gansu province at the upper part of the adsorption layer (3), wherein the soil layer height is 20 cm, punching two small holes with the diameter of 0.2 cm from the outside of the device, and connecting the electrodes respectively; Step six, selecting calamus as a plant treatment unit on the surface of the soil layer, and uniformly adding 2 g of hematite and 10 mL of lactobacillus bacteria liquid on the surface; And seventhly, a peristaltic pump is connected to the upper part of the soil layer, the total concentration of Cr (VI) solution with the concentration of 30 mg/L is continuously input to the peristaltic pump for 2L, and the treated solution is collected at the bottom of the device.
10. An application mode of a novel light-driven ecological wetland system device based on the system device and the construction method of the system device as claimed in claims 1-9, which is characterized in that the application mode comprises the following steps: Firstly, domesticating wetland plants, namely selecting well-grown calamus which is common wetland plants purchased from Jiangsu dormitory, transporting the calamus back to a laboratory, washing the calamus with tap water, placing the calamus into a 20L glass jar filled with tap water and a glass jar capable of submerging root water for cultivation, adding organic culture solution into water according to the volume ratio of 1:50, aerating and cultivating for 21 days, and then selecting plants which are similar in posture and weight and well-grown to be transplanted into a wetland system; Step two, the microorganism lactobacillus used for experiments is from a laboratory of geology science and mineral resources college of Lanzhou university in Gansu province, the lactobacillus is obtained from the lactobacillus fermentation strain of Nanjing Chaner biotechnology limited company as the original form, and the lactobacillus growing to the logarithmic phase is selected to be added into a wetland system; And thirdly, after the constructed wetland is successfully built, closing an upper valve and a lower valve of the wetland, preparing 2L tap water, adding 6 mL of 10 g/L Cr (VI) solution into the constructed wetland system, enabling the Cr (VI) concentration of the system to reach 30 mg/L, performing static operation, enabling plants in the system to survive stably, and testing the Cr (VI) concentration in the system every 1h from the beginning of adding.

Description

Construction and application of novel light-driven ecological wetland system device Technical Field The invention relates to the technical field of environmental engineering and artificial wetland, in particular to a novel semiconductor mineral-based artificial wetland system applied to treatment of Cr (VI) containing mine wastewater. Background Along with the continuous evolution and promotion of industrial revolution, the economic rapid development of China inevitably causes the problem of water pollution of related ecological environment, and along with the natural water circulation, the polluted wastewater can enter human bodies, animals and plants, and serious harm can be brought to human health, animal and plant growth and even the whole ecological system. The water pollution can be classified into organic pollution, inorganic pollution and heavy metal pollution. Wherein heavy metal pollution seriously affects human health along with water circulation. At present, the treatment of the environmental pollution wastewater mainly comprises a physical method, a chemical method and a biological method, wherein the biological method has the advantages of low cost, green and sustainable property and the like, and is widely applied, but the current biological method treatment device has single pertinence and the wastewater treatment efficiency is to be improved. How to skillfully combine a physical method and a biological method to construct a novel wastewater treatment device, thereby improving the degradation efficiency of complex wastewater and becoming a current research hot spot. The artificial wetland is a sewage natural treatment technology which simulates the function of a natural wetland ecosystem and is designed, constructed and managed manually. The core principle is that organic matters, nitrogen and phosphorus nutrients, heavy metals and pathogens in the sewage are removed through the synergistic effect of matrixes, plants, microorganisms and water bodies. In recent years, the constructed wetland is widely focused in the field of environmental treatment due to the advantages of low operation cost, wide treatment range, environmental protection, wide applicable pollution source types, sustainable treatment and the like, and various fields of scholars develop and widely study on various aspects of reaction configurations, filling materials, biological types and the like of the constructed wetland, so that three configurations of the surface flow constructed wetland, the horizontal subsurface flow constructed wetland and the vertical subsurface flow constructed wetland are gradually formed. Research shows that the removal rate of the constructed wetland system to the Cr (VI) mine wastewater with the concentration of 20 mg/L reaches 60 percent. Most of microorganisms utilized by the existing constructed wetlands are anaerobic microorganisms, and the removal of heavy metal ions, nitrate and other pollutants is closely related to the oxygen content of the water body. Because the constructed wetland has strong fluidity and higher oxygen content in surface wastewater, the constructed wetland has the defects of lower degradation rate of polluted wastewater, incomplete and unstable removal of pollutants such as heavy metal ions, longer degradation period and the like. In recent years, the development of geological microorganisms has provided many new ideas and elicitations for the field of environmental remediation. Recent researches show that under the surface environment, semiconductor minerals can generate mineral photoelectrons after photoholes are captured by reducing substances under the illumination condition, and non-photosynthetic microorganisms can obtain the energy of natural semiconductor minerals to obviously grow. In addition, natural semiconductor minerals such as hematite, molybdenite and the like can be used as microbial extracellular electron mediators to promote the reduction of heavy metal ions, nitrate and other inorganic ions by electroactive microorganisms. Meanwhile, research shows that the soil MFC externally connected with the solar cell can drive in-situ soil electrogenesis microorganisms to degrade pollutants, and the pollutant removal rate is greatly improved after hematite is added into the system, so that solar energy is successfully introduced into soil environment treatment. The sunlight-mineral-microorganism interaction which is not widely focused in the nature is widely involved in the material exchange and energy flow processes on the earth surface for a long time, and the microorganism self-purification process in the natural environment is enhanced in situ. Based on the above, we combine the solar-mineral-microorganism fuel cell system with the artificial wetland system, artificially add lactobacillus community and hematite into the surface layer of the system, and aim to develop a novel efficient, energy-saving, green and environment-friendly ecological wetland system