Preparation method of a complex microbial growth-promoting agent for targeted killing of water sponges in rivers and lakes

Abstract

The present application relates to water treatment agent preparation technical field, disclose a kind of river and lake water spongy target killing composite microbial growth-promoting agent preparation method, the method includes: preparation includes sodium percarbonate, L-glutamic acid-N,N-diacetic acid tetrasodium and polyaspartic acid granule A;Preparation includes humic acid sodium, adipic acid, sodium erythorbic acid and ferric citrate granule B;Granule A and granule B are jointly put into mixing machine and mixed uniformly, after discharging, vacuum sealing packaging is carried out.The present application realizes the physical isolation of oxidizing agent and reducing agent by extruding granulation respectively, to avoid the early failure of agent during storage period.After input into water body, the difference in physical strength of two types of granules is used to realize time sequence disintegration, granule A disintegrates first to build alkaline de-crosslinking environment to strip water spongy defense layer, and granule B disintegrates subsequently to make microenvironment drift to weak acidity, trigger fenton-like reaction to release hydroxyl radical to complete targeted killing, and oxygen release and carbon and nitrogen source dissolution can promote water bottom micro-ecosystem reconstruction.

Description

Technical Field

[0001] This invention relates to the field of water treatment agent preparation technology, specifically to a method for preparing a compound microbial growth-promoting agent for targeted killing of Spirogyra in rivers and lakes. Background Technology

[0002] Currently, the problem of Spirogyra proliferation caused by eutrophication in rivers and lakes is becoming increasingly prominent. Spirogyra is a multicellular filamentous green algae. In eutrophic waters, it easily proliferates excessively and covers the water surface. Large areas of Spirogyra obstruct sunlight penetration, inhibiting the photosynthesis of submerged plants at the bottom. When Spirogyra colonies decay and decompose, they consume large amounts of dissolved oxygen, easily leading to severe oxygen deficiency in the bottom waters. The living space of native aquatic organisms is squeezed, and the original benthic ecological balance of the water body is disrupted.

[0003] To address the aforementioned needs for treating Spirogyra, conventional chemical treatment methods often employ powder-mixed agents. During preparation, powdered raw materials containing strong oxidants, metal catalysts, and other chemical auxiliaries are directly added to the same equipment for physical mixing. The uniformly mixed composite powder is then packaged in moisture-proof bags and used as the finished product. During on-site application, workers directly sprinkle the dry powder into the target water body. Upon entering the water, all chemical components of the agent dissolve simultaneously. The dissolved substances of different properties mix instantaneously in the localized water area, triggering an oxidation process. The chemical substances released by the agent directly adhere to the surface of the algae and take effect.

[0004] The aforementioned direct mixing method of powders fails to resolve the coexistence conflict between raw materials. Strong oxidizing substances and reducing components are in direct physical contact. The finished product is prone to slight hygroscopic absorption during storage and transportation, potentially triggering premature redox depletion reactions. A large amount of active ingredient becomes ineffective before application. Spirogyra cell walls are encased in a highly water-repellent pectin protective layer. Existing drug components dissolve simultaneously upon entering water, resulting in a fixed pH in the underwater microenvironment. Without a prior local alkalinity stripping process, subsequently generated oxidizing active substances cannot penetrate the pectin network. Internal organelles are difficult to completely destroy. A single chemical reaction process cannot improve bottom water quality. The bottom water body cannot receive a continuous supply of dissolved oxygen. In-situ indigenous aerobic microorganisms lack necessary carbon and nitrogen nutrients. The water body loses its ability to autonomously repair its micro-ecosystem.

[0005] Therefore, this invention provides a method for preparing a compound microbial growth-promoting agent for targeted killing of Spirogyra in rivers and lakes, in order to overcome the shortcomings of the prior art. Summary of the Invention

[0006] To address the shortcomings of existing technologies, this invention provides a method for preparing a compound microbial growth-promoting agent for targeted killing of Spirogyra in rivers and lakes. This method solves the problems of existing agents failing to penetrate the water-repellent defense layer composed of pectin on the outer layer of Spirogyra cell walls, resulting in low killing efficiency. Furthermore, the conventional method of mixing oxidants and reducing catalysts in the preparation process easily leads to redox reactions during storage, causing the agent to become ineffective prematurely. Additionally, it is difficult to achieve temporal regulation of the microenvironment pH after being introduced into the water, thus failing to establish an ecological foundation conducive to the proliferation of beneficial microorganisms at the bottom layer.

[0007] To achieve the above objectives, the present invention provides the following technical solution: a method for preparing a compound microbial growth-promoting agent for targeted killing of Spirogyra in rivers and lakes, comprising the following steps: Prepare raw materials containing sodium percarbonate, tetrasodium L-glutamic acid-N,N-diacetate and polyaspartic acid according to the formula, and obtain granules A after mixing, extrusion granulation; Prepare raw materials containing sodium humate, adipic acid, sodium isoascorbate and ferric citrate according to the formula, and obtain granules B by mixing, extrusion and granulation. The particles A and B are fed into a mixer and continuously mixed until uniform. After discharge, the mixture is vacuum-sealed and packaged to obtain the composite microbial growth promoter.

[0008] By adopting the above technical solution, this invention achieves targeted cell wall disruption and deep elimination of Spirogyra through a combination of spatial physical isolation and time-sequential chemical release mechanisms. The specific reaction and mechanism of action are carried out according to the following steps: The first step is physical isolation to prevent failure. Particles A and B are prepared separately using an extrusion granulation process, which macroscopically blocks the direct physical contact between the oxidant sodium percarbonate, the reducing agent sodium isoascorbate, and the catalyst ferric citrate, thus avoiding ineffective consumption of the reagents during preparation and storage.

[0009] The second step is alkaline decrosslinking and stripping. After the agent is added to the water, particle A disintegrates first, and sodium percarbonate dissociates upon contact with water, releasing sodium carbonate and hydrogen peroxide. Sodium carbonate establishes initial alkaline conditions in the local microenvironment of the water. Under this alkaline environment, tetrasodium L-glutamate-N,N-diacetate dissociates and targets the crosslinked calcium ions that provide structural support in the pectin of Spirogyra cell walls, forming a soluble chelate. This process dismantles the water-repellent defense layer surrounding Spirogyra, exposing its internal cellular structure.

[0010] The third step is the dynamic shift of the microenvironment over time. Particle B subsequently disintegrates in the water, releasing adipic acid and hydrogen ions, which neutralize the alkalinity generated by sodium carbonate in the early stage, causing the local microenvironment's liquid phase pH to dynamically shift from the initial alkaline state to a slightly acidic state.

[0011] The fourth step is Fenton-like catalytic oxidation. In a weakly acidic microenvironment, ferric citrate dissociates into ferric ions, which are then reduced to ferrous ions by sodium isoascorbate as a reducing agent. The generated ferrous ions then undergo a Fenton-like reaction with hydrogen peroxide in the environment. This reaction continuously releases highly oxidizing hydroxyl radicals, which directly oxidize and cleave the cell membranes and organelles of Spirogyra cells that have lost their pectin defense layer, thus achieving targeted killing.

[0012] The fifth step is microecological reconstruction. The remaining hydrogen peroxide from the decomposition of sodium percarbonate gradually releases oxygen in the water, increasing the dissolved oxygen concentration in the bottom waters. Polyaspartic acid and sodium humate, after dissolving, serve as carbon and nitrogen sources, providing metabolic substrates for beneficial aerobic microorganisms native to the water, promoting microbial community reproduction and the restoration of the bottom ecosystem.

[0013] Preferably, in the step of preparing particle A, particle A is made from raw materials comprising the following mass percentages: sodium percarbonate 65.0%–75.0%, tetrasodium L-glutamic acid-N,N-diacetate 18.0%–22.0%, and polyaspartic acid 5.0%–15.0%; in the step of preparing particle B, particle B is made from raw materials comprising the following mass percentages: sodium humate 35.0%–45.0%, adipic acid 25.0%–35.0%, sodium isoascorbate 15.0%–25.0%, and ferric citrate 5.0%–15.0%.

[0014] By adopting the above technical solution, the reasonable mass ratio of each component is limited, ensuring that the hydrogen ion equivalent released by adipic acid can accurately neutralize the hydroxide ion equivalent generated by sodium percarbonate, so that the pH drift endpoint of the microenvironment can accurately stay in the weakly acidic range suitable for the occurrence of Fenton-like reactions, thus ensuring the generation yield of hydroxyl radicals.

[0015] Preferably, in the step of continuously mixing the particles A and B together in a mixer, 40.0% to 60.0% of particle A and 40.0% to 60.0% of particle B are weighed and mixed by mass percentage.

[0016] By adopting the above technical solution, the macroscopic material balance is maintained, with particle A providing alkalinity and substrate, and particle B providing acidity and catalytic system, ensuring the uniformity and stability of the mixed reagent during application.

[0017] Preferably, in the step of preparing particle A, the relative humidity of the production workshop is controlled at 25% or below, and the ambient temperature is controlled at 15-25℃; in the step of preparing particle B, the relative humidity of the environment is controlled at 30% or below, and the ambient temperature is controlled at 15-25℃.

[0018] By adopting the above technical solution, the moisture adsorption and thermodynamic state of polar raw materials during processing are controlled, preventing sodium percarbonate and sodium isoascorbate from spontaneously decomposing due to moisture, and maintaining the chemical activity of the pharmaceutical raw materials.

[0019] Preferably, the specific implementation method for preparing granules A is as follows: the raw materials are fed into a pulverizer to be pulverized and sieved to collect fine powder with a particle size of 150-200 mesh; the obtained fine powder is fed into a mixer and continuously mixed at a speed of 15-25 r / min for 15-30 min; the mixed dry powder is fed into a double-roll extrusion granulator through a forced feeder, the temperature of the circulating chilled water inside the rolls is set to 10-20℃, and the pressure of the double-roll hydraulic system is set to 10-15 MPa; after extrusion into flakes, the particles are coarsely crushed and cut into granules A with a particle size of 2.0-3.0 mm.

[0020] Preferably, the specific method for preparing particle B is as follows: sodium humate is directly sieved to obtain 60-80 mesh powder without pulverization; adipic acid, sodium isoascorbate, and ferric citrate are lightly pulverized and sieved to obtain 80-100 mesh powder; the obtained powder is put into a mixer and continuously mixed at a speed of 15-25 r / min for 20-40 min; the mixed powder is fed into a roller extrusion granulator, and the pressure of the roller hydraulic system is set to 20-25 MPa; after extruding into hard tablets, the tablets are coarsely crushed and granulated to obtain particles B with a particle size of 3.0-5.0 mm.

[0021] Preferably, the pressure of the roller hydraulic system set in the step of preparing particle B is greater than the pressure of the roller hydraulic system set in the step of preparing particle A, and the cut-off particle size of particle B is greater than the cut-off particle size of particle A.

[0022] By adopting the above technical solution, differentiated parameters in terms of physical compressive strength and geometric dimensions were established between particles A and B. Lower granulation pressure and smaller particle size endow particles A with higher porosity and specific surface area, enabling them to have a faster hydration rate after entering water, thus disintegrating first to complete alkalinity release and de-crosslinking. Higher granulation pressure and larger particle size endow particles B with a denser internal structure, resulting in delayed dissolution after entering water, thereby forming a temporal dynamic drift phenomenon of pH in the system's microenvironment. This difference in physical configuration is the engineering basis for the sequential triggering of chemical mechanisms.

[0023] Preferably, the specific implementation method of continuously mixing the particles A and B together in the mixer is as follows: the particles A and B are jointly fed into a gravity-type non-destructive mixer and continuously mixed for 5 to 10 minutes at a rotation speed of 5 to 20 r / min.

[0024] By adopting the above technical solution, gravity flipping is used instead of high-intensity mechanical shearing and stirring. This achieves a uniform distribution of the two types of particles in macroscopic space, while avoiding wear and breakage of the particle surface and maintaining the original particle size and dissolution kinetics.

[0025] Preferably, in the step of preparing particle A, the pulverizer is a pulverizer with a water-cooled jacket; in both the steps of preparing particle A and preparing particle B, the mixing is carried out in a V-type asymmetric mixer.

[0026] By adopting the above technical solutions, the water-cooled jacket eliminates the accumulation of mechanical heat generated during the pulverization process, ensuring the stability of heat-sensitive components; the asymmetric configuration eliminates mixing dead zones and improves the microscopic dispersion uniformity of multi-component raw materials in the dry powder phase.

[0027] Preferably, in the extrusion granulation steps for preparing particles A and particles B, after the particles are extruded, they are coarsely crushed using a crusher and then passed through a vibrating screen for particle size selection.

[0028] By adopting the above technical solutions, the granulation process after tableting is standardized, ensuring that the particle size distribution of the finally collected particles is concentrated, and making the underwater disintegration rate highly controllable.

[0029] This invention provides a method for preparing a compound microbial growth-promoting agent for targeted killing of Spirogyra in rivers and lakes. It has the following beneficial effects: 1. This invention employs a separate extrusion granulation technique to physically separate particles A containing the oxidant sodium percarbonate from particles B containing the reducing agent sodium isoascorbate and the catalyst ferric citrate. This method blocks the direct contact interface between the oxidant and the reducing agent, preventing premature redox reactions during preparation, transportation, and storage, maintaining the chemical stability of each active component, and thus extending the effective shelf life of the drug.

[0030] 2. This invention, by setting differentiated roller granulation pressures and cut-off particle sizes, enables particles A and B to possess different physical strengths and specific surface areas. Upon introduction into water, the loosely structured and smaller particle A first disintegrates, releasing alkalinity and de-crosslinking agents, thus stripping away the outer cell wall structure of Spirogyra. The denser and larger particle B then disintegrates with a delayed effect, releasing acidic substances to adjust the local water environment to a slightly acidic state, thereby triggering a Fenton-like reaction that releases hydroxyl radicals. This physical structure design achieves temporal dynamic drift of the pH in the underwater microenvironment, completing the process of first breaking down the cell walls of Spirogyra and then precisely oxidizing it to kill it.

[0031] 3. After the compound agent of this invention completes its killing effect, the hydrogen peroxide remaining from the decomposition of sodium percarbonate can continuously release oxygen into the water, increasing the dissolved oxygen concentration in the bottom water area. Simultaneously, the polyaspartic acid and sodium humate in the components dissolve and serve as carbon and nitrogen sources. These substances together provide essential metabolic substrates and a suitable living environment for indigenous aerobic microorganisms in the water, promoting the proliferation of beneficial microbial communities and the restoration of the bottom water micro-ecosystem while eliminating Spirogyra. Attached Figure Description

[0032] Figure 1 This is a diagram showing the evolution of microenvironment parameters in the system after the agent of this invention is introduced into water; Figure 2 This is a comparison chart showing the dynamic changes in the concentration of free calcium ions in the supernatant of the present invention. Detailed Implementation

[0033] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0034] The main raw materials and reagents used in the following examples and comparative examples have the following sources and specifications. Reagents not specifically mentioned are all commercially available analytical grade or higher grade products.

[0035] Sodium percarbonate, CAS No. 15630-89-4, molecular formula 2Na2CO3·3H2O2, industrial-grade coated sodium percarbonate with a sodium silicate protective layer and an effective oxygen content ≥13.0% is selected. L-Glutamic acid-N,N-diacetic acid tetrasodium, CAS No. 51981-21-6, molecular formula C9H9NNa4O8, industrial-grade solid dry powder is selected. Polyaspartic acid, CAS No. 181828-06-8, is a homopolymer, solid dry powder with a weight average molecular weight of 2000 to 8000 Da is selected. Sodium humate, CAS No. 68131-04-4, industrial-grade dry powder with a humic acid content ≥60.0% is selected. Adipic acid, CAS No. 124-04-9, molecular formula C6H... 10O4, industrial grade product selected. Sodium isoascorbate, CAS No. 6381-77-7, molecular formula C6H7NaO6·H2O, industrial grade product selected. Ferric citrate, CAS No. 118-52-5, molecular formula C6H5FeO7, industrial grade solid powder selected. The general industrial equipment used in the embodiments and comparative examples of this invention includes a pulverizer with a water-cooled jacket and equipped with a filter screen, a V-type asymmetric mixer, a double-roll extrusion granulator with a hydraulic system and an internal circulating water cooling system for the rolls, a gravity-type non-destructive mixer, and a vibrating screen. The hydraulic system of the double-roll extrusion granulator has an adjustable working pressure range of 10MPa to 30MPa, and the surface temperature of the rolls can be forcibly cooled and maintained at 25°C or below.

[0036] Preparation Examples 1-3: Preparation Example 1: This preparation example provides a method for preparing intermediate particles, including the preparation of particles A1 and B1, specifically including the following steps: Preparation of Granules A1: Weigh out 65.0% sodium percarbonate, 20.0% tetrasodium L-glutamic acid-N,N-diacetate, and 15.0% polyaspartic acid by mass percentage. Maintain the relative humidity of the production workshop at 25% or below and the ambient temperature at 15℃. Feed the above raw materials into a water-cooled jacketed pulverizer for separate pulverization and sieving, collecting fine powder with a particle size of 150 mesh. Add the obtained fine powder to a V-type asymmetric mixer and mix continuously for 15 minutes at a speed of 15 r / min. Feed the mixed dry powder into a double-roll extrusion granulator via a forced feeder, setting the internal circulating chilled water temperature of the rolls to 10℃ and the hydraulic system pressure of the rolls to 10 MPa. After extrusion into flakes, the granules are coarsely crushed by a toothed roll crusher and then pass through a vibrating screen to cut particles with a particle size of 2.0 mm, thus obtaining granules A1.

[0037] Preparation of Granules B1: Weigh out 45.0% sodium humate, 25.0% adipic acid, 15.0% sodium isoascorbate, and 15.0% ferric citrate by mass percentage. Maintain the relative humidity at 30% or below and the ambient temperature at 15℃. Sieve the sodium humate directly to obtain 60-mesh powder without further pulverization. Lightly pulverize the adipic acid, sodium isoascorbate, and ferric citrate in a pulverizer and sieve to obtain 80-mesh powder. Add the obtained powder to a V-type asymmetric mixer and mix continuously for 20 minutes at 15 r / min. Feed the mixed powder into a roller extrusion granulator, setting the hydraulic system pressure to 20 MPa. After extruding into hardened tablets, coarsely crush them in a crusher, and then pass them through a vibrating screen to obtain particles with a diameter of 3.0 mm, thus obtaining granules B1.

[0038] Preparation Example 2: This preparation example provides a method for preparing intermediate particles, including the preparation of particles A2 and B2, specifically including the following steps: Preparation of Granules A2: Weigh out 70.0% sodium percarbonate, 20.0% tetrasodium L-glutamic acid-N,N-diacetate, and 10.0% polyaspartic acid by mass percentage. Maintain the relative humidity of the production workshop at 25% or below and the ambient temperature at 20℃. Feed the above raw materials into a water-cooled jacketed pulverizer for separate pulverization and sieving, collecting fine powder with a particle size of 175 mesh. Add the obtained fine powder to a V-type asymmetric mixer and mix continuously for 22 minutes at a speed of 20 r / min. Feed the mixed dry powder into a double-roll extrusion granulator via a forced feeder, setting the internal circulating chilled water temperature of the rolls to 15℃ and the hydraulic system pressure of the rolls to 12.5 MPa. After extrusion into flakes, the granules are coarsely crushed by a toothed roll crusher and then pass through a vibrating screen to cut particles with a particle size of 2.5 mm, thus obtaining granules A2.

[0039] Preparation of Granules B2: Weigh out 40.0% sodium humate, 30.0% adipic acid, 20.0% sodium isoascorbate, and 10.0% ferric citrate by mass percentage. Maintain an ambient relative humidity of 30% or below and an ambient temperature of 20℃. Sift the sodium humate directly through a sieve to obtain 70-mesh powder without further pulverization. Lightly pulverize the adipic acid, sodium isoascorbate, and ferric citrate in a pulverizer and sieve to obtain 90-mesh powder. Add the obtained powder to a V-type asymmetric mixer and mix continuously at 20 r / min for 30 min. Feed the mixed powder into a roller extrusion granulator, setting the hydraulic system pressure to 22.5 MPa. After extruding into hard tablets, coarsely crush the tablets in a crusher, and then pass them through a vibrating screen to obtain 4.0 mm particles, thus obtaining granules B2.

[0040] Preparation Example 3: This preparation example provides a method for preparing intermediate particles, including the preparation of particles A3 and B3, specifically including the following steps: Preparation of Granules A3: Weigh out 75.0% sodium percarbonate, 20.0% tetrasodium L-glutamic acid-N,N-diacetate, and 5.0% polyaspartic acid by mass percentage. Maintain the relative humidity of the production workshop at 25% or below and the ambient temperature at 25℃. Feed the above raw materials into a water-cooled jacketed pulverizer for separate pulverization and sieving, collecting fine powder with a particle size of 200 mesh. Add the obtained fine powder to a V-type asymmetric mixer and mix continuously for 30 minutes at a speed of 25 r / min. Feed the mixed dry powder into a double-roll extrusion granulator via a forced feeder, setting the internal circulating chilled water temperature of the rolls to 20℃ and the hydraulic system pressure of the rolls to 15 MPa. After extrusion into flakes, the granules are coarsely crushed by a toothed roll crusher, and then pass through a vibrating screen to cut particles with a particle size of 3.0 mm, thus obtaining granules A3.

[0041] Preparation of Granules B3: Weigh out 35.0% sodium humate, 35.0% adipic acid, 25.0% sodium isoascorbate, and 5.0% ferric citrate by mass percentage. Maintain an ambient relative humidity of 30% or below and an ambient temperature of 25℃. Sieve the sodium humate directly to obtain 80-mesh powder without further pulverization. Lightly pulverize the adipic acid, sodium isoascorbate, and ferric citrate in a pulverizer and sieve to obtain 100-mesh powder. Add the obtained powder to a V-type asymmetric mixer and mix continuously at 25 r / min for 40 min. Feed the mixed powder into a roller extrusion granulator, setting the hydraulic system pressure to 25 MPa. After extruding into hardened tablets, coarsely crush them in a crusher, and then pass them through a vibrating screen to obtain 5.0 mm particles, thus obtaining granules B3.

[0042] Examples 1-3: Example 1: This embodiment provides a method for preparing a compound microbial growth-promoting agent for targeted killing of Spirogyra in rivers and lakes, including the following steps: Weigh 40.0% of granules A1 and 60.0% of granules B1 obtained in Preparation Example 1 by mass percentage. Add both granules to a gravity-type non-destructive mixer and mix continuously for 5 minutes at a speed of 5 r / min to achieve a macroscopically uniform distribution of granules A1 and B1. Discharge the homogeneous mixture and vacuum-seal it in a packaging bag to obtain the composite microbial growth promoter for targeted killing of Spirogyra in rivers and lakes.

[0043] Example 2: This embodiment provides a method for preparing a compound microbial growth-promoting agent for targeted killing of Spirogyra in rivers and lakes, including the following steps: Weigh 50.0% of particle A2 and 50.0% of particle B2 obtained in Preparation Example 2 by mass percentage. Add both particles to a gravity-type non-destructive mixer and mix continuously for 8 minutes at 12 r / min to achieve a macroscopically uniform distribution of particles A2 and B2. Discharge the homogeneous mixture and vacuum-seal it in a packaging bag to obtain the composite microbial growth promoter for targeted killing of Spirogyra in rivers and lakes.

[0044] Example 3: This embodiment provides a method for preparing a compound microbial growth-promoting agent for targeted killing of Spirogyra in rivers and lakes, including the following steps: Weigh 60.0% of particle A3 and 40.0% of particle B3 obtained in Preparation Example 3 by mass percentage. Add both particles to a gravity-type non-destructive mixer and mix continuously for 10 minutes at 20 r / min to achieve a macroscopically uniform distribution of particles A3 and B3. Discharge the homogeneous mixture and vacuum-seal it in a packaging bag to obtain the composite microbial growth promoter for targeted killing of Spirogyra in rivers and lakes.

[0045] Comparative Examples 1-5: Comparative Example 1: Compared with Example 2, the difference is that the targeting and timing control system of the present invention was removed, only sodium percarbonate was retained in the formulation, all other components were removed and replaced with an equal mass of conventional commercial biological agents, and no physical isolation and granulation process was performed, but they were directly mixed, and everything else was the same.

[0046] Comparative Example 2: Compared with Example 2, the difference is that instead of physically isolating particles A2 and B2, all raw materials in the formula are pulverized to 200 mesh, placed in the same mixer for homogeneous mixing, and pressed into homogeneous composite single particles under a single pressure of 15 MPa. The rest are the same.

[0047] Comparative Example 3: Compared with Example 2, the difference is that: the tetrasodium L-glutamic acid-N,N-diacetate in the granule A2 formulation was removed and replaced with an equal mass of anhydrous sodium sulfate, while the rest are the same.

[0048] Comparative Example 4: Compared with Example 2, the difference is that adipic acid and ferric citrate in the granule B2 formulation were removed, and an equal mass of anhydrous sodium sulfate was used as a placeholder; otherwise, they are the same.

[0049] Comparative Example 5: Compared with Example 2, the difference is that although the separate granulation and isolation of particles A and B are retained, the crushing mesh size, extrusion pressure (both uniformly set to 15MPa) and the particle size of the final screened particles A and B are completely set to be the same, and no dissolution kinetic pressure difference or particle size difference is formed. All other aspects are the same.

[0050] Test Examples 1-4: Test Example 1: Dynamic pH Shift and Hydroxyl Radical Release Kinetics in a Microenvironment Liquid Phase Experimental description: A simulated lake bottom buffer water containing sodium bicarbonate and calcium chloride was prepared as the reaction substrate and transferred to a reactor with a water-cooled jacket. The circulating water was turned on to maintain the system temperature at a constant 20°C.

[0051] Insert the composite electrode of the multi-channel online pH meter into the specified depth below the surface of the reaction liquid, perform baseline calibration, and then start the continuous data recording mode.

[0052] The test compound granules of reagent of a set mass were added into the reactor, and the mechanical stirring was turned on. The speed was set to 30 revolutions per minute to simulate the slow water flow at the bottom.

[0053] Liquid phase samples were extracted from the central region of the reaction system using a pipette at 5, 15, 30, and 60 minutes after the reagent was added to the water.

[0054] Immediately after sampling, a fixed concentration of spin trapping agent DMPO was added to the sample. After vortex mixing and volume adjustment, the sample was transferred to a quartz capillary.

[0055] The sample inside the quartz capillary was scanned and analyzed using an electron paramagnetic resonance spectrometer, and the relative signal intensity values ​​characterizing the spin adduct of hydroxyl radicals were read and recorded.

[0056] Experimental data: Table 1. Dynamic data of pH over time and site-directed monitoring of hydroxyl radicals in the liquid microenvironment of Example 2.

[0057] in conclusion: according to Figure 1 Based on the data and the measurement results in Table 1, the pH continuous monitoring curve in the figure shows a rapid upward trend in the first 5 minutes of the reaction system during the initial dosing phase. At the 5th minute, the pH discrete measurement point corresponding to the left axis reaches a peak of 9.63, while the hydroxyl radical signal intensity indicated by the right axis is at a low level of 14.2. During this stage, particles A with lower compressive strength in the system undergo structural disintegration first, and the sodium percarbonate inside dissolves and hydrolyzes, producing sodium carbonate and hydrogen peroxide, resulting in a strongly alkaline system. The increased alkalinity provides a suitable initial exfoliation environment for the formulation components. Due to the lack of catalytic conditions, hydrogen peroxide mainly accumulates during this stage and does not undergo large-scale dissociation.

[0058] Subsequently, the pH curve showed a smooth downward inflection point. By the 15th minute, the pH value at the measurement point had dropped to 8.79, and the hydroxyl radical signal intensity had only slightly increased to 42.6, indicating that the system was still in the alkaline inhibition and substrate accumulation phase.

[0059] Between 15 and 30 minutes, the pH curve showed a significant decline. At the 30-minute mark, the pH measurement point on the left axis reached its lowest point of 6.18, indicating that the system had crossed the neutral zone and entered a weakly acidic environment. Simultaneously, the dashed line representing the hydroxyl radical signal intensity in the graph sharply increased, reaching a peak of 876.5 on the right axis. This indicates that particles B, with higher compressive strength, disintegrated significantly during this period, releasing acidic substances that neutralized the previously accumulated alkalinity. This weakly acidic environment activated the homologous metal ions and reducing agents released from particles B, prompting a vigorous Fenton-like catalytic reaction in the accumulated hydrogen peroxide within the system, resulting in the concentrated release of a large number of hydroxyl radicals.

[0060] By the 60-minute mark, the pH of the system slightly increased and stabilized at 6.52, while the hydroxyl radical signal intensity curve dropped back to 433.1. This indicates that the core catalytic phase of the system has ended, and it has entered a long-term sustained-release stable period. The test data above, which link physical isolation granulation with the chemical microenvironment, verify that the design mechanism of controlling the stepwise release of reagent components through pressure difference and then utilizing pH time-series drift to control the burst of oxidative activity is feasible.

[0061] Test Example 2: Specific Chemical Quantitative Test for Depolymerization of Pectin Calcium Bridges in Spirogyra Dense Clusters Experimental description: Fresh Spirogyra during its peak bloom was collected from natural water bodies and rinsed repeatedly with deionized water under slow flow to remove surface impurities and free calcium salts. After draining the surface moisture, two Spirogyra clumps, each weighing 50.0 grams wet, were collected.

[0062] The weighed Spirogyra samples were placed in two reaction tanks containing 500 ml of deionized water, left to stand for 5 minutes, and the initial background concentration of free calcium ions in the water was measured and recorded.

[0063] The calibrated calcium ion selective composite electrode was inserted into the supernatant of the two reaction tanks, connected to a multi-channel data acquisition instrument, and the sampling frequency was set to once per second to start continuous monitoring.

[0064] Turn on the mechanical agitator of the reaction tank and set the rotation speed to 20 revolutions per minute. Simultaneously add equal masses of the reagent prepared in Example 2 and the reagent prepared in Comparative Example 3 to the two reaction tanks respectively.

[0065] The dynamic changes in free calcium ion concentration were continuously monitored and recorded over 30 minutes. At the 10th and 30th minutes of the reaction, 5 ml samples of the supernatant were extracted from the middle layer of the reaction tank using a syringe.

[0066] The extracted supernatant sample was filtered through a 0.22-micron microporous membrane and then injected into an ion chromatograph for re-quantitative analysis of calcium ion concentration.

[0067] Experimental data: Table 2. Data on the release of free calcium ions from interwoven Spirogyra clumps

[0068] in conclusion: according to Figure 2 The data in the graph shows the reaction time (min) on the horizontal axis and the free calcium ion concentration (mg / L) on the vertical axis. The solid black line representing Example 2, monitored continuously, shows a steep upward trend in the initial reaction stage (0-10 min), with a large slope, indicating that a large amount of calcium ions within the Spirogyra interlocking clusters are stripped and released into the aqueous phase in a short time. From 10 to 30 min, the upward trend of the solid black line gradually slows down and stabilizes at a high level, indicating that the bindable calcium ions on the Spirogyra surface have been sufficiently extracted. The dashed gray line representing Comparative Example 3, monitored continuously, remains at a low level, with a gentle overall trend and a weak release. The significant difference in the curve shapes between the two examples indicates that the addition of tetrasodium L-glutamic acid-N,N-diacetate in the formulation is the direct factor promoting the large-scale release of free calcium ions.

[0069] According to Table 2 and Figure 2 The data in the figure are marked with black boxes for sampling points in Example 2, and precisely marked on the horizontal and vertical axes by dashed lines. In Example 2, the concentration of free calcium ions in the supernatant reached 47.38 mg / L at 10 min, rising to 56.12 mg / L at 30 min. The surge in free calcium in the test system originated from the calcium pectate layer on the outer layer of the Spirogyra cell wall. The L-glutamic acid-N,N-diacetic acid tetrasodium released after particle A disintegrated first exhibited a strong metal ion chelating ability in the locally alkaline environment, specifically capturing cross-linked calcium ions from the pectin network structure, leading to the disintegration of the calcium bridge structure. Without the support of the calcium bridges, the dense pectin defense layer of Spirogyra underwent physical swelling and structural disintegration, eliminating the water repulsion effect of the dense clusters. The sampling points in Comparative Example 3 are represented by gray triangles in the figure, also marked on the axes by dashed lines. In Comparative Example 3, under conditions lacking tetrasodium L-glutamate-N,N-diacetate, the free calcium ion concentrations at 10 min and 30 min were only 3.85 mg / L and 7.04 mg / L, respectively. This trace amount of free calcium is attributed to non-specific dissolution caused by the natural metabolism of Spirogyra or mechanical agitation. The data confirms that, in the absence of a specific chelating agent, conventional agents cannot break down the pectin cross-linking network on the Spirogyra surface. The retention of the pectin layer hinders the subsequent penetration of reactive oxygen species and agent components. This quantitative chemical test confirms the effectiveness of the target chelating agent in this scheme in dismantling the Spirogyra's water-repellent defense layer mechanism.

[0070] Test Example 3: Finished Product Explosion-Proof Storage and Accelerated Aging Stability Test Experimental description: The vacuum-sealed packaged products prepared in Examples 1, 2, 3 and Comparative Example 2 were taken. Each test sample was accurately weighed to a mass of 1.00 kg and placed in a high and low temperature alternating damp heat test chamber with a pre-set temperature of 50℃ and a relative humidity of 75%.

[0071] The test chamber was set to run continuously for 14 days, during which time the macroscopic morphological changes of each group of sample packaging bags were recorded daily through the test chamber's observation window.

[0072] After the 14-day accelerated aging cycle, all samples were removed from the test chamber and cooled at room temperature for 2 hours. The volume expansion of each group of packaging bags was measured using the water displacement gas collection method, and the expansion volume per kilogram of sample was calculated.

[0073] After unpacking each group of samples, quickly use an infrared thermometer to record the center temperature of the internal materials and assess the internal heating status.

[0074] The effective oxygen content of the material was determined by potassium permanganate titration. Multiple random samples were taken from each group of unpacked materials, mixed and ground, and 0.2000 g of powder was accurately weighed and dissolved in deionized water containing an appropriate amount of dilute sulfuric acid.

[0075] The above solution was titrated with a 0.1 mol / L potassium permanganate standard solution of the specified concentration until the solution turned slightly red and did not fade within half a minute, which was the titration endpoint. The volume of potassium permanganate solution consumed was recorded, the effective oxygen mass fraction of each group of samples after aging was calculated, and the effective oxygen retention rate was obtained by combining the initial effective oxygen content before aging.

[0076] Experimental data: Table 3. Storage stability test data of each sample after 14 days of accelerated aging.

[0077] in conclusion: According to the data in Table 3, after 14 days of accelerated aging under high temperature and humidity, Examples 1 to 3 maintained effective oxygen retention rates of 95.84%, 96.69%, and 94.89%, respectively. The gas volume in the packaging bags was less than 5 mL / kg, the packaging remained tight, and no abnormal temperature rise was detected in the center of the material after unpacking. These data demonstrate the practical effectiveness of the two-component physical isolation granulation process in explosion-proof storage. During the preparation process, the relative humidity was controlled at a low level, and sodium percarbonate, which exhibits strong oxidizing properties, was granulated separately from sodium isoascorbate and ferric citrate, which possess reducing and catalytic properties, thus blocking the direct physical contact interface between the oxidant and the reducing agent. This spatial isolation cuts off the electron transfer and ion migration pathways in the solid-phase system, inhibiting the spontaneous decomposition of sodium percarbonate induced by high temperature and humidity. In Comparative Example 2, due to the lack of material isolation, all raw materials were mixed, pulverized, and compressed into homogeneous particles. The effective oxygen retention rate decreased to 36.11%, and the gas volume in the packaging bag reached 2145.6 mL / kg, accompanied by significant system self-heating. This data indicates that when oxidants and reductants are in full contact within the same particle system, environmental thermal stress and trace moisture infiltration can rapidly trigger catalytic side reactions at the gas-solid interface. Localized moisture-induced chain-like exothermic decomposition generates a large amount of oxygen, causing the vacuum packaging to bulge and posing a risk of thermal runaway and spontaneous combustion during storage. The comparative data from this test case confirms the necessity of physical isolation structures for maintaining the thermodynamic stability of source-containing composite agents and ensuring the safety of industrial storage.

[0078] Test Example 4: Practical Water Body Simulation Benthic Ecosystem Promotion and Spirogyra Elimination Efficacy Test Experimental description: Multiple 50-liter glass microcosm water tanks were constructed, with a 5-centimeter-thick layer of natural lake sediment evenly laid at the bottom. 40 liters of filtered natural lake water were slowly poured in, and the tanks were left to stand for 48 hours to allow the bottom sediment-water interface to reach physical and chemical equilibrium.

[0079] Equal amounts of fresh Spirogyra filaments in the logarithmic growth phase were inoculated into each water tank and placed in an artificial climate chamber. The tanks were then cultured continuously for 20 days under conditions of a 12-hour light cycle and a constant temperature of 25°C, until the Spirogyra proliferated in the water and formed large-scale, explosive, interwoven, and dense clusters.

[0080] The initial wet weight of Spirogyra before dosing was measured and recorded for each water tank, and the initial dry weight was calculated based on the pre-determined moisture content of Spirogyra. The agents prepared in Examples 1 to 3, as well as Comparative Examples 1, 3, 4, and 5, were evenly sprinkled into different water tanks at a uniform dosage of 50 grams per cubic meter of water.

[0081] After the chemical was added, the water tanks were kept running under the original light and temperature conditions for 14 days. At the end of the experimental cycle, all the remaining spirulina in each water tank was removed using a nylon screen with a pore size of 0.15 mm, and the surface deposits were rinsed with deionized water.

[0082] The remaining Spirogyra was placed in a constant temperature drying oven at 80℃ and dried until constant weight. The final dry weight was weighed using an analytical balance, and the Spirogyra dry weight removal rate was calculated.

[0083] Using a portable dissolved oxygen meter, insert the probe 2 cm above the mud-water interface at the bottom of the water tank to measure and record the dissolved oxygen concentration in the bottom water.

[0084] Water samples were collected 5 cm above the mud-water interface using a sterile water sampler. After serial dilution with sterile physiological saline, the samples were spread onto beef extract peptone agar plates and incubated upside down in a 30°C incubator for 48 hours. The abundance of benthic aerobic bacteria was then determined using the plate count method.

[0085] Experimental data: Table 4. 14-Day Microcosm Water Tank Comprehensive Water Purification Efficiency Evaluation Test Data

[0086] in conclusion: According to the data in Table 4, after 14 days of treatment in Examples 1 to 3, the dry weight removal rate of Spirogyra reached 92.34% to 96.71%, the dissolved oxygen concentration in the bottom water increased to the range of 6.75 mg / L to 7.28 mg / L, and the abundance of benthic aerobic bacterial communities increased to 2.14 × 10⁻⁶. 6 CFU / mL up to 3.48 × 10⁻⁶ 6 The results, at the CFU / mL level, validated the combined water purification efficiency of the two-component sequential dissolution mechanism in macroscopic water bodies. The system disintegrated the calcium pectate cross-linking network on the surface of Spirogyra through the release of alkalinity and chelating agents. The subsequent decrease in microenvironment pH triggered a Fenton-like catalytic reaction, resulting in the concentrated release of hydroxyl radicals that caused complete oxidative deconstruction of the Spirogyra cells, which had lost their protective layer. The large amount of oxygen released from the decomposition of sodium percarbonate altered the anaerobic state of the substrate, providing ample electron acceptors for the proliferation and expansion of native benthic aerobic microorganisms.

[0087] Comparative Example 1 used a conventional commercial biological agent, achieving a Spirogyra dry weight removal rate of only 24.18%. The dissolved oxygen and aerobic bacteria abundance at the bottom layer were low, demonstrating that conventional agents struggle to penetrate the dense pectin hydrophobic layer of Spirogyra and thus fail to achieve substantial killing effects. Comparative Example 3 removed tetrasodium L-glutamate-N,N-diacetate from the formulation, reducing the Spirogyra dry weight removal rate to 41.53%. The lack of a specific chelation decrosslinking mechanism prevented the agent from breaking through the Spirogyra's network protective structure, and the oxidant dissipated in the external aqueous phase, failing to induce oxidative stress within the target. Comparative Example 4 removed adipic acid and ferric citrate, achieving a Spirogyra removal rate of 53.42%. This indicates that when the system loses acid-base time-shifting and coordination catalysis, hydrogen peroxide generated solely from the hydrolysis of sodium percarbonate cannot trigger a free radical chain reaction with a high oxidation potential, making it difficult to disintegrate large-area intertwined Spirogyra clumps. Comparative Example 5, where components were homogeneously mixed and granulated under a single pressure, showed a decrease in Spirogyra removal rate to 32.75%, and a significantly lower dissolved oxygen level at the bottom (3.98 mg / L). These data indicate that without physical isolation and pressure differential control of dissolution kinetics, acidic and alkaline components are simultaneously released and neutralized in the aqueous phase, while oxidizing and reducing components undergo instantaneous ineffective self-consumption within the particles. Most of the effective active substances decay and are lost before penetrating to the Spirogyra's target site, rendering the system ineffective in targeted killing and unable to provide a continuous oxygen source for the benthic aerobic ecosystem.

Claims

1. A preparation method of a complex microbial growth-promoting agent for targeted killing of lake and river water mites, characterized in that, Includes the following steps: Prepare raw materials containing sodium percarbonate, tetrasodium L-glutamic acid-N,N-diacetate and polyaspartic acid according to the formula, and obtain granules A after mixing, extrusion granulation; Prepare raw materials containing sodium humate, adipic acid, sodium isoascorbate and ferric citrate according to the formula, and obtain granules B by mixing, extrusion and granulation. The particles A and B are fed into a mixer and continuously mixed until uniform. After discharge, the mixture is vacuum-sealed and packaged to obtain the composite microbial growth promoter.

2. The preparation method of the complex microbial growth-promoting agent for targeting and killing lake and river mosses according to claim 1, characterized in that, In the step of preparing particle A, particle A is made from the following raw materials in the following mass percentages: Sodium percarbonate 65.0%–75.0%, tetrasodium L-glutamic acid-N,N-diacetate 18.0%–22.0%, polyaspartic acid 5.0%–15.0%; In the step of preparing particle B, particle B is made from the following raw materials in the following mass percentages: Sodium humate 35.0%–45.0%, adipic acid 25.0%–35.0%, sodium isoascorbate 15.0%–25.0%, ferric citrate 5.0%–15.0%.

3. The preparation method of the complex microbial growth-promoting agent for targeting and killing lake and river mosses according to claim 1, characterized in that, In the step of continuously mixing particles A and B together in a mixer, 40.0% to 60.0% of particles A and 40.0% to 60.0% of particles B are weighed and mixed by mass percentage.

4. The method for preparing the compound microbial growth-promoting agent for targeted killing of Spirogyra in rivers and lakes according to claim 1, characterized in that, In the step of preparing particle A, the relative humidity of the production workshop is controlled at 25% or below, and the ambient temperature is controlled at 15-25℃. In the step of preparing particle B, the relative humidity of the production workshop is controlled at 30% or below, and the ambient temperature is controlled at 15-25℃.

5. The method for preparing the compound microbial growth-promoting agent for targeted killing of Spirogyra in rivers and lakes according to claim 1, characterized in that, The specific method for preparing particle A is as follows: The raw materials are fed into a pulverizer to be pulverized and sieved separately, and fine powder with a particle size of 150-200 mesh is collected. The resulting fine powder is put into a mixer and continuously mixed at a speed of 15-25 r / min for 15-30 min. The mixed dry powder is fed into the double-roll extrusion granulator through a forced feeder. The temperature of the internal circulating chilled water of the rolls is set to 10-20℃, and the pressure of the hydraulic system of the double rolls is 10-15MPa. After extrusion, the material is coarsely crushed and cut into particles A with a particle size of 2.0 to 3.0 mm.

6. The method for preparing the compound microbial growth-promoting agent for targeted killing of Spirogyra in rivers and lakes according to claim 1, characterized in that, The specific method for preparing particle B is as follows: Sodium humate is directly sieved to obtain 60-80 mesh powder without being crushed. Adipic acid, sodium isoascorbate, and ferric citrate are lightly crushed and sieved to obtain 80-100 mesh powder. The obtained powder is put into a mixer and continuously mixed at a speed of 15-25 r / min for 20-40 min. The mixed powder is fed into a double-roller extrusion granulator, and the pressure of the double-roller hydraulic system is set to 20-25 MPa. After being extruded into hard tablets, the tablets are coarsely crushed and granules B with a particle size of 3.0–5.0 mm are extracted.

7. The method for preparing the compound microbial growth-promoting agent for targeted killing of Spirogyra in rivers and lakes according to claim 1, characterized in that, The pressure of the roller hydraulic system set in the step of preparing particle B is greater than the pressure of the roller hydraulic system set in the step of preparing particle A, and the cut-off particle size of particle B is greater than the cut-off particle size of particle A.

8. The method for preparing the compound microbial growth-promoting agent for targeted killing of Spirogyra in rivers and lakes according to claim 1, characterized in that, The specific method for continuously mixing particles A and B together in a mixer is as follows: Particle A and particle B are fed together into a gravity-type non-destructive mixer and continuously mixed for 5 to 10 minutes at a speed of 5 to 20 r / min.

9. The method for preparing the compound microbial growth-promoting agent for targeted killing of Spirogyra in rivers and lakes according to claim 1, characterized in that, In the step of preparing particle A, the pulverizer is a pulverizer with a water-cooled jacket; In both the preparation of particle A and the preparation of particle B, the mixing is carried out in a V-type asymmetric mixer.

10. The method for preparing the compound microbial growth-promoting agent for targeted killing of Spirogyra in rivers and lakes according to claim 1, characterized in that, In the extrusion granulation steps for preparing particles A and particles B, the materials are extruded into flakes and then coarsely crushed using a crusher before being fed into a vibrating screen for particle size selection.

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