Self-sinking type aquatic plant ecological restoration module with multi-stage carbon source slow-release function and preparation method

Abstract

The present application belongs to the field of water environment ecological restoration and engineering technology, and discloses a self-sinking water plant ecological restoration module with multi-stage carbon source slow-release function and a preparation method. The ecological restoration module comprises a plant layer, a flexible slow-release base layer and a composite functional filler layer. The flexible slow-release base layer is a double-layer or multi-layer net structure, each layer of which is formed by mixing and weaving at least two kinds of natural fiber materials with different degradation periods after pre-fermentation treatment. The composite functional filler layer is filled between the adjacent two layers of net structures of the flexible slow-release base layer. The material of the composite functional filler layer comprises volcanic rock, modified zeolite, hydroxyl iron adsorption filler, sawdust after pre-fermentation treatment and liquid composite microbial agent. The plants of the plant layer are water plants with root systems penetrating the flexible slow-release base layer and growing in the composite functional filler layer. The ecological restoration module is an innovative ecological restoration module integrating multi-stage carbon source slow-release, microbial loading, self-sinking paving and wide adaptability.

Description

Technical Field

[0001] This invention belongs to the field of water environment ecological restoration and engineering technology, and more specifically, relates to a self-sinking aquatic plant ecological restoration module with multi-level carbon source slow release function and its preparation method. Background Technology

[0002] Utilizing aquatic plants for water purification and ecological restoration is a green and sustainable technological approach. However, traditional direct planting methods are susceptible to water erosion and have low survival rates, while existing modular technologies still have many limitations. For example, the module disclosed in CN209563253U relies on a fixed column structure, which has poor applicability on hard substrates and does not consider the issue of carbon source replenishment. CN115428710A uses sphagnum moss wrapping and plant root matrix, but its structural strength and long-term purification stability are insufficient. CN118421062A focuses on using synthetic biodegradable materials such as PLA for seagrass, but its degradation products and slow-release characteristics are not well-suited to the microbial systems of freshwater bodies. CN112919638A requires the construction of a semi-enclosed purification zone using an impermeable structure, which is complex to construct and lacks flexibility. Especially in eutrophic water bodies with reclaimed water as the water source or low C / N ratio, insufficient carbon source required for denitrification becomes a key limiting factor for nitrogen removal efficiency. Therefore, it can be seen that existing technologies lack a convenient solution that can systematically and progressively provide carbon sources while integrating adsorption, microbial degradation, and phytoremediation functions.

[0003] Therefore, the present invention aims to provide a self-sinking aquatic plant ecological restoration module with multi-level carbon source slow release function and its preparation method. Summary of the Invention

[0004] The purpose of this invention is to address the shortcomings of existing technologies by proposing a self-sinking aquatic plant ecological restoration module with multi-level carbon source slow-release function and its preparation method. The ecological restoration module of this invention is an innovative module integrating multi-level carbon source slow release, microbial loading (microbial enhanced purification), self-sinking paving, and wide applicability.

[0005] To achieve the above objectives, the first aspect of the present invention provides a self-sinking aquatic plant ecological restoration module with multi-level carbon source slow-release function, the ecological restoration module comprising a plant layer, a flexible slow-release base layer and a composite functional filler layer; The flexible slow-release base layer is a double-layer or multi-layer mesh structure, and each layer of mesh structure is woven from at least two kinds of natural fiber materials with different degradation cycles after pre-fermentation treatment. The composite functional filler layer is filled between two adjacent mesh structures of the flexible slow-release base layer; the material of the composite functional filler layer includes solid materials and liquid composite microbial agents, the solid materials include volcanic rock, modified zeolite, hydroxyl iron adsorbent filler and sawdust after pre-fermentation treatment; The plants in the plant layer are aquatic plants whose roots penetrate the flexible slow-release base layer and are implanted in the composite functional filler layer.

[0006] According to the present invention, preferably, the microorganisms in the liquid composite microbial agent include nitrifying bacteria and denitrifying bacteria; the concentration of microorganisms in the composite functional filler layer is 10. 6 -10 7 CFU / mL.

[0007] According to the present invention, preferably, based on the total weight of the solid materials of the composite functional filler layer, the content of volcanic rock is 50-60%, the content of modified zeolite is 30-40%, the content of hydroxyl iron adsorbent is 5-10%, and the content of sawdust after pre-fermentation is 1-5%.

[0008] According to the present invention, preferably, the method for preparing the composite functional filler layer is as follows: (1) The volcanic rock, modified zeolite, hydroxyl iron adsorbent and sawdust after pre-fermentation are mixed evenly to obtain a mixed filler; (2) The diluted liquid composite microbial agent is sprayed onto the mixed packing material and pre-activated and cultured to obtain the composite functional packing layer.

[0009] According to the present invention, preferably, the pre-activation culture conditions include: a closed or semi-closed environment with 60%-80% humidity, an activation temperature of 15-30°C, and an activation time of 2-5 days.

[0010] In this invention, the composite functional filler layer is composed of volcanic rock, modified zeolite, hydroxyl iron adsorption filler and pre-fermented sawdust in a specific ratio, and is loaded with composite microbial agents. Therefore, the composite functional filler layer integrates pollutant adsorption, microbial loading and ballast functions.

[0011] In this invention: Volcanic rock: forms a porous framework, providing a huge specific surface area for microbial attachment; Modified zeolite: obtained by soaking zeolite in alkaline solution, modified zeolite can selectively adsorb ammonium nitrogen (NH4). + ); Hydroxyferric adsorption packing: specifically designed for adsorbing phosphate (PO4). 3- It has an adsorption capacity as high as 22.5 mg / g; Sawdust: After pre-fermentation, it can be used as a short-term carbon source that is easily degradable, and can quickly activate microbial activity; Liquid composite microbial agent: Sprayed into the composite functional packing layer during preparation, containing nitrifying bacteria and denitrifying bacteria, allowing the microorganisms to adapt to the environment in advance and initially colonize in the pores of the packing.

[0012] According to the present invention, preferably, each layer of the mesh structure is woven from a mixture of pre-fermented palm fiber and pre-fermented hemp fiber.

[0013] In this invention, since each layer of the flexible slow-release base layer is woven from a mixture of at least two natural fiber materials with different degradation cycles after pre-fermentation treatment, each layer of the flexible slow-release base layer is a biodegradable mesh structure. The flexible slow-release base layer of this invention is used to fix plants, bind fillers, and provide multi-stage carbon source slow release.

[0014] According to the present invention, preferably, the palm fiber, hemp fiber, and sawdust undergo the same pre-fermentation treatment, which includes: S1: Spray palm fiber, hemp fiber and sawdust with urea solution to obtain palm fiber pile, hemp fiber pile and sawdust pile respectively; S2: The palm fiber pile, hemp fiber pile and sawdust pile are subjected to pile fermentation respectively.

[0015] According to the present invention, preferably, before the pre-fermentation treatment, the mass ratio of palm fiber, hemp fiber and sawdust is (3-5):(2-4):(1-3).

[0016] According to the present invention, preferably, the ratio of the mass of urea in the urea aqueous solution, the mass of water in the urea aqueous solution, to the total mass of palm fiber, hemp fiber and sawdust before the pre-fermentation treatment is (0.5-1.2):(45-65):100.

[0017] According to the present invention, preferably, the operating conditions for the pile fermentation include: the temperature of the palm fiber pile, the hemp fiber pile and the sawdust pile are each independently controlled at 25-55℃; the pile fermentation time is 20-45 days, and the pile is turned over once every 7-15 days, for a total of 2-3 times.

[0018] In this invention, the pre-fermentation treatment is crucial. It breaks down the wax and pectin on the surface of the materials, making them more readily utilized by microorganisms and preventing rapid decomposition in water that could lead to secondary pollution. The fiber material of the flexible slow-release base layer and the sawdust of the composite functional filler layer in this invention are both pre-fermented to remove interfering substances and activate carbon source release capabilities. Palm fiber has a long degradation cycle (>1 year), providing a long-lasting carbon source; hemp fiber has a medium degradation cycle (5-12 months), providing a medium-efficiency carbon source; and the sawdust of the composite functional filler layer serves as a readily degradable short-term (2-6 months) carbon source supplement, and can also quickly initiate microbial activity. The combination of palm fiber, hemp fiber, and sawdust forms a multi-level carbon source slow-release system, continuously providing electron donors for aquatic microorganisms, especially denitrifying bacteria.

[0019] The present invention also specifically sets the component ratio of "palm fiber, hemp fiber and sawdust". The targeted component ratio, combined with the pre-fermentation treatment, enables precise and controllable release of carbon source, that is, it achieves precise control of carbon source release rate and cycle.

[0020] According to the present invention, preferably, the aquatic plant is selected according to the target water body conditions, and is preferably at least one of Vallisneria natans, Nymphoides peltata, Hydrilla verticillata and Ceratophyllum demersum.

[0021] In this invention, the composite functional filler layer is filled between two adjacent mesh structures of the flexible slow-release base layer and compacted to a predetermined thickness. Then, the flexible slow-release base layer is sewn and sealed with biodegradable hemp rope. At the same time, the side of the ecological restoration module of this invention can be provided with connectors for splicing multiple ecological restoration modules of this invention together, which facilitates large-scale splicing and laying.

[0022] The second aspect of this invention provides a method for preparing the self-sinking aquatic plant ecological restoration module with multi-level carbon source slow-release function, the preparation method comprising the following steps: S1: Each layer of the flexible slow-release base layer is woven from a mixture of at least two natural fiber materials with different degradation cycles after pre-fermentation treatment. S2: The composite functional filler layer is filled between two adjacent mesh structures of the flexible slow-release base layer; S3: After the roots of the aquatic plants penetrate the flexible slow-release base layer and are implanted into the composite functional filler layer, the ecological restoration module is maintained by wet method. The ecological restoration module is obtained after the aquatic plants take root.

[0023] According to the present invention, preferably, the conditions for wet cultivation include: water depth of 5-30cm, water temperature of 15-30℃, and wet cultivation cycle of 15-30 days, thereby promoting plant rooting and system maturation through wet cultivation.

[0024] In this invention, the ecological restoration module is a modular aquatic plant cultivation system suitable for various underwater conditions, possessing multi-level carbon source slow release and microbial enhanced purification functions, and has a three-layer integrated structure. The preparation method of the ecological restoration module is a standardized method, ensuring the consistency and effectiveness of product performance.

[0025] The beneficial effects of the technical solution of this invention are as follows: The ecological restoration module of this invention is an innovative ecological restoration module integrating multi-level carbon source slow release, microbial loading (microbial enhanced purification), self-sinking paving, and wide applicability. This ecological restoration module is a rationally structured, easy-to-install, and long-term stable water purification module, especially effective in solving the problem of insufficient carbon sources in water bodies. Specifically: 1. Innovative multi-stage carbon source slow release system: Through the combination of natural fiber materials with different degradation cycles and pre-fermentation treatment process, the carbon source is released on demand and continuously, effectively purifying water quality and fundamentally solving the bottleneck problem of insufficient denitrification carbon source in scenarios such as reclaimed water.

[0026] 2. Synergistic triple purification of "adsorption-biochemical-absorption": The composite functional filler layer of the present invention is responsible for physical adsorption and microbial transformation, the aquatic plants in the plant layer of the present invention are responsible for absorption and oxygen transport, and the carbon source in the ecological restoration module of the present invention can drive denitrification. The synergy of the three (i.e., the multi-path synergy of "physical adsorption-microbial degradation-plant absorption") makes the denitrification and phosphorus removal efficiency of the ecological restoration module of the present invention high and stable.

[0027] 3. Dual-functional integrated design of physical carrier and biological carbon source: The composite functional filler layer in this invention fills the interlayer between two adjacent mesh structures of the flexible slow-release base layer, enabling the flexible slow-release base layer to perform the function of a "physical carrier". This achieves the integrated function of the flexible slow-release base layer as both a "physical carrier" and a "biological carbon source".

[0028] 4. Combining immediate and long-term effectiveness: Material pretreatment (pre-fermentation treatment) and microbial preactivation (pre-activation culture) ensure that the ecological restoration module of this invention can quickly start the purification function after being put into use; the gradient carbon source design ensures the long-term operating effect of the ecological restoration module of this invention.

[0029] 5. High engineering applicability: The ecological restoration module of this invention achieves self-sinking by relying on the self-weight of the composite functional filler layer, without the need for additional ballast or fixing devices. This self-sinking design of the composite functional filler layer of this invention is suitable for various water conditions (soft / hard water bodies). The modular design of the ecological restoration module of this invention facilitates transportation, laying and subsequent maintenance. The main materials are environmentally friendly and do not cause secondary pollution.

[0030] Other features and advantages of the present invention will be described in detail in the following detailed description section. Detailed Implementation

[0031] Preferred embodiments of the invention will now be described in more detail. While preferred embodiments of the invention are described below, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that the invention will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

[0032] In the following embodiments: Modified zeolite is obtained by soaking zeolite in an alkaline solution; The hydroxyl iron adsorption packing material was purchased from Watch Water GmbH, Germany, using FERROLOX® (IRON HYDROXIDEBASED GRANULES) adsorbent. The liquid composite microbial agent is a microbial agent containing nitrifying bacteria and denitrifying bacteria, and the effective viable count needs to be ≥10. 8 CFU / mL, commercially available options are acceptable; During the preparation of the composite functional packing layer, the liquid composite microbial agent is diluted with water and sprayed onto the mixed packing material to ensure that the concentration of microorganisms in the composite functional packing layer is 10. 6 -10 7 CFU / mL; Palm fiber, jute fiber, pine sawdust, and dwarf valerian seedlings are all commercially available.

[0033] Example 1

[0034] This embodiment provides a self-sinking aquatic plant ecological restoration module (100cm×100cm×7cm) with multi-level carbon source slow release function. The ecological restoration module includes a plant layer, a flexible slow-release base layer and a composite functional filler layer.

[0035] The flexible slow-release base layer has a double-layer mesh structure. Each layer of the mesh structure is woven from a mixture of pre-fermented palm fiber and pre-fermented jute fiber. The total thickness of the flexible slow-release base layer is 2cm.

[0036] The composite functional filler layer is filled between the two mesh structures of the flexible slow-release base layer (the composite functional filler layer is compressed to a thickness of 5 cm, and the flexible slow-release base layer is sewn and sealed with biodegradable hemp rope); the materials of the composite functional filler layer include solid materials and liquid composite microbial agents, the solid materials include 55 kg of volcanic rock with a particle size of 5-10 mm, 36 kg of modified zeolite, 7 kg of hydroxyl iron adsorbent, and 2 kg of pre-fermented pine sawdust; the preparation method of the composite functional filler layer is as follows: (1) Mix the volcanic rock, modified zeolite, hydroxyl iron adsorbent filler and pre-fermented pine sawdust evenly to obtain a mixed filler; (2) Spray 4L of diluted liquid compound microbial agent onto the mixed packing material, stir, cover and keep moist, and pre-activate and culture at 25-30℃ for 3 days to obtain the composite functional packing layer (the concentration of microorganisms in the composite functional packing layer is 10). 6 -10 7 (CFU / mL).

[0037] The plant layer consists of robust, dwarf Vallisneria seedlings, spaced at 16 plants / m². 2 The density of the soil is such that its roots penetrate the flexible slow-release base layer and are implanted into the composite functional filler layer. Then, the module planted with dwarf Vallisneria seedlings is moved to a maintenance pond with a water depth of 10-15cm (water temperature 15-30℃) for wet maintenance for 25 days to obtain the ecological restoration module.

[0038] The palm fiber, jute fiber, and pine sawdust undergo the same pre-fermentation treatment, which includes: S1: Spray palm fiber, jute fiber and pine sawdust with urea solution to obtain palm fiber piles, jute fiber piles and pine sawdust piles; Prior to the pre-fermentation treatment, the mass ratio of palm fiber, jute fiber, and pine sawdust was 4.2:3.5:2; The ratio of the mass of urea in the urea aqueous solution, the mass of water in the urea aqueous solution, to the total mass of palm fiber, jute fiber, and pine sawdust before pre-fermentation is 1:60:100. S2: The palm fiber pile, jute fiber pile, and pine sawdust pile are subjected to pile fermentation respectively; The operating conditions for the pile fermentation include: maintaining humidity; independently controlling the temperature of the palm fiber pile, jute fiber pile, and pine sawdust pile at 25-55℃; and the pile fermentation time is 30 days, with the pile turned over every 15 days, for a total of 2 times.

[0039] Field Application: The wet-cured ecological restoration modules were directly placed into an urban landscape water body supplemented with reclaimed water. The ecological restoration modules of this invention quickly sank and adhered to the bottom sediment. The ecological restoration modules of this embodiment are equipped with rope connectors on their sides, allowing 100 modules to be joined together to form a 100m section. 2 The repair area.

[0040] Effect test: Apply the above 100m 2After three months of follow-up monitoring of the water quality in the remediation area, the results showed that the average removal rate of total nitrogen (TN) in the water reached 72%, the average removal rate of total phosphorus (TP) reached 68%, the water transparency increased from 0.3m to 0.8m, the plants in the module grew vigorously, and the ecosystem was well established.

[0041] The various embodiments of the present invention have been described above. These descriptions are exemplary and not exhaustive, nor are they limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments.

Claims

1. A self-sinking aquatic plant ecological restoration module with multi-level carbon source slow release function, characterized in that, The ecological restoration module includes a plant layer, a flexible slow-release base layer, and a composite functional filler layer; The flexible slow-release base layer is a double-layer or multi-layer mesh structure, and each layer of mesh structure is woven from a mixture of pre-fermented palm fiber and pre-fermented hemp fiber. The composite functional filler layer is filled between two adjacent mesh structures of the flexible slow-release base layer; the material of the composite functional filler layer includes solid materials and liquid composite microbial agents, the solid materials include volcanic rock, modified zeolite, hydroxyl iron adsorbent filler and sawdust after pre-fermentation treatment; The method for preparing the composite functional filler layer is as follows: (1) The volcanic rock, modified zeolite, hydroxyl iron adsorbent and sawdust after pre-fermentation are mixed evenly to obtain a mixed filler; (2) The diluted liquid composite microbial agent is sprayed onto the mixed packing material, and after pre-activation culture, the composite functional packing layer is obtained; The plants in the plant layer are aquatic plants whose roots penetrate the flexible slow-release base layer and are implanted into the composite functional filler layer; The aquatic plant in question is *Vallisneria natans*.

2. The self-sinking aquatic plant ecological restoration module with multi-level carbon source slow release function according to claim 1, wherein, The microorganisms in the liquid composite microbial agent include nitrifying bacteria and denitrifying bacteria; the concentration of microorganisms in the composite functional filler layer is 10. 6 -10 7 CFU / mL; Based on the total weight of the solid materials in the composite functional filler layer, the content of volcanic rock is 50-60%, the content of modified zeolite is 30-40%, the content of hydroxyl iron adsorbent filler is 5-10%, and the content of sawdust after pre-fermentation treatment is 1-5%.

3. The self-sinking aquatic plant ecological restoration module with multi-level carbon source slow release function according to claim 1, wherein, The pre-activation culture conditions include: a closed or semi-closed environment with 60%-80% humidity, an activation temperature of 15-30℃, and an activation time of 2-5 days.

4. The self-sinking aquatic plant ecological restoration module with multi-level carbon source slow release function according to claim 1, wherein, The palm fiber, hemp fiber, and sawdust undergo the same pre-fermentation treatment, which includes: S1: Spray palm fiber, hemp fiber and sawdust with urea aqueous solution to obtain palm fiber pile, hemp fiber pile and sawdust pile respectively; S2: The palm fiber pile, hemp fiber pile and sawdust pile are subjected to pile fermentation respectively.

5. The self-sinking aquatic plant ecological restoration module with multi-level carbon source slow release function according to claim 4, wherein, Before the pre-fermentation treatment, the mass ratio of palm fiber, hemp fiber and sawdust was (3-5):(2-4):(1-3); The ratio of the mass of urea in the urea aqueous solution, the mass of water in the urea aqueous solution, to the total mass of palm fiber, hemp fiber, and sawdust before the pre-fermentation treatment is (0.5-1.2):(45-65):100; The operating conditions for the composting fermentation include: the temperature of the palm fiber pile, the hemp fiber pile, and the sawdust pile are each independently controlled between 25-55℃; The fermentation process takes 20-45 days, with the pile turned over every 7-15 days, for a total of 2-3 times.

6. The preparation method of the self-sinking aquatic plant ecological restoration module with multi-level carbon source slow release function as described in any one of claims 1-5, characterized in that, The preparation method includes the following steps: S1: Each layer of the flexible slow-release base layer is woven from a mixture of pre-fermented palm fiber and pre-fermented hemp fiber. S2: The composite functional filler layer is filled between two adjacent mesh structures of the flexible slow-release base layer; S3: After the roots of the aquatic plants penetrate the flexible slow-release base layer and are implanted into the composite functional filler layer, the ecological restoration module is wet-maintained to obtain the ecological restoration module.

7. The preparation method of the self-sinking aquatic plant ecological restoration module with multi-level carbon source slow release function according to claim 6, wherein, The conditions for wet curing include: water depth of 5-30cm, water temperature of 15-30℃, and a wet curing cycle of 15-30 days.