Closed hydroponic device using ozone water circulation sterilization
By using a closed hydroponic device and ozone water circulation disinfection technology, the problems of microbial contamination and maintenance difficulties in traditional hydroponic systems have been solved, resulting in a highly efficient and safe hydroponic system.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- HUBEI FORBON TECH
- Filing Date
- 2025-08-11
- Publication Date
- 2026-07-14
AI Technical Summary
Traditional hydroponic systems suffer from severe microbial contamination, harmful chemical disinfectant residues, incomplete UV disinfection with high maintenance costs, and low ozone disinfection efficiency with insufficient sealing, leading to system maintenance difficulties and safety hazards.
It adopts a closed hydroponic device, combined with ozone water circulation disinfection and catalytic decomposition of exhaust gas. It uses a Venturi jet to efficiently dissolve ozone, dynamically adjust the ozone concentration, and use activated carbon to filter residual ozone, achieving efficient sterilization and ensuring safety.
It achieves efficient sterilization, reduces maintenance costs, improves sterilization efficiency, ensures plant safety, reduces harmful substance residues, and lowers operational risks.
Smart Images
Figure CN224482475U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of soilless agricultural cultivation technology, specifically relating to a closed hydroponic device that utilizes ozone water circulation for disinfection, suitable for factory-style hydroponic vegetable cultivation, plant factories, urban agriculture, and organic and pollution-free vegetable production. Background Technology
[0002] (I) Development and Challenges of Hydroponics
[0003] Hydroponics is a highly efficient soilless cultivation technology that directly provides water and nutrients to plants through a nutrient solution. It boasts advantages such as water conservation, high yield, and efficient space utilization, and is widely used in plant factories, greenhouse agriculture, and urban vertical farms. However, traditional hydroponic systems have the following problems:
[0004] 1. Microbial contamination: Long-term recycling of nutrient solutions can easily lead to the growth of bacteria (such as Pythium and Fusarium), fungi, and algae, resulting in root diseases (such as root rot) and affecting crop growth.
[0005] 2. Currently used disinfection methods (such as chemical agents and ultraviolet (UV) light) have the following technical shortcomings:
[0006] Limitations of chemical disinfectants: Commonly used disinfectants (such as sodium hypochlorite and hydrogen peroxide) may leave harmful residues, do not meet organic farming standards, and long-term use can easily lead to drug resistance in pathogens, reducing their bactericidal effect; frequent addition of agents is required, increasing labor costs and environmental burden.
[0007] The limitations of ultraviolet (UV) disinfection: it can only disinfect water flowing through UV lamps locally and cannot continuously inhibit the regeneration of microorganisms in nutrient solutions; UV lamps are prone to scaling and need to be cleaned or replaced regularly, resulting in high maintenance costs.
[0008] 3. High system maintenance costs: Frequent replacement of nutrient solution or cleaning of pipelines increases the consumption of manpower and resources.
[0009] (II) Agricultural Applications of Ozone Disinfection Technology
[0010] Ozone (O3) is a strong oxidant with broad-spectrum bactericidal properties (bacteria, viruses, spores), leaves no residue, and decomposes into oxygen (O2). It has been used in food processing, medical applications, and water treatment. In agriculture, ozone applications include:
[0011] 1. Irrigation water disinfection: It can kill pathogens in the water source, but the concentration needs to be controlled to avoid plant toxicity.
[0012] 2. Air purification in the facility: Reduces the risk of mold and pest spread in the greenhouse.
[0013] 3. Nutrient solution treatment: Experiments show that low concentrations of ozone can inhibit algae growth and degrade organic pollutants.
[0014] Problems with traditional ozone disinfection methods:
[0015] 1. Low ozone utilization: Traditional aeration methods have poor dissolution efficiency, and ozone is easy to escape, resulting in incomplete disinfection or waste.
[0016] 2. Concentration control challenge: Too high an ozone concentration can damage plant roots, while too low a concentration cannot effectively sterilize the plant. Precise control is required.
[0017] 3. Insufficient system sealing: Traditional hydroponic devices come into contact with the external environment, which may introduce new pathogens, and ozone leakage may endanger the health of operators. Summary of the Invention
[0018] In order to overcome the problems existing in the prior art, this utility model provides a closed hydroponic device that uses ozone water circulation disinfection. It achieves efficient sterilization through ozone water circulation disinfection technology, the closed design prevents ozone leakage, and the catalytic decomposition of exhaust gas ensures operational safety. The ozone dosage is dynamically adjusted to balance the sterilization effect and plant safety, achieving residue-free and highly efficient sterilization.
[0019] The present invention adopts the following technical solution:
[0020] A closed hydroponic device utilizing ozone water circulation for disinfection includes a closed planting trough, an ozone generator, pipes, a Venturi jet injector, a buffer tank, a water pump, and a PLC controller. The closed planting trough is characterized by having an inlet and an outlet; the water pump is placed inside the buffer tank; the outlet of the closed planting trough is connected sequentially to the Venturi jet injector and the connected buffer tank via pipes; the water pump outlet is connected to the inlet of the closed planting trough via a pipe; the ozone generator outlet is connected to the negative pressure port of the Venturi jet injector via a pipe; the PLC controller controls the water pump and the ozone generator; and the buffer tank has a material addition port and an exhaust port.
[0021] The bottom of the enclosed planting trough is lined with activated carbon, which allows residual ozone gas to be filtered and catalytically decomposed by the activated carbon in the planting trough.
[0022] This utility model also includes an integrated sensor that integrates a pH sensor, an EC sensor, and an ORP sensor, an ORP sensor, and a flow meter. The integrated sensor is installed inside a buffer tank, the ORP sensor is installed inside a Venturi jet injector, and the flow meter is installed on the pipe at the outlet of the ozone generator. The pH sensor, EC sensor, ORP sensor, and flow meter in the integrated sensor are respectively connected to a PLC controller.
[0023] This utility model also includes an oxygenation pump and a DO sensor, which are placed in a closed planting trough. The DO sensor is connected to a PLC controller, and the PLC controller controls the oxygenation pump.
[0024] The buffer tank is equipped with baffles to ensure that residual ozone is degraded into oxygen within the buffer tank, with an ORP < 450mV, thus avoiding oxidative damage to hydroponic seedlings.
[0025] A hydroponic method using a closed-loop hydroponic device with ozone water circulation disinfection, characterized by comprising the following steps:
[0026] Step 1: Seedling Transplanting: In a sterile environment, transplant the seedlings onto the planting baskets in the closed planting trough, turn on the nutrient solution circulation, and adjust the pH of the nutrient solution to 6.0-7.0, the electrical conductivity EC to 1.5-2.0 mS / cm, and the dissolved oxygen to 8-10 mg / L.
[0027] Step 2: Periodic ozone disinfection: Starting on the 7th day after transplanting, ozone water circulation disinfection is activated for 30 minutes in each 7-day cycle.
[0028] Step 3: Ozone water circulation disinfection: The nutrient solution returning from the closed planting trough is transported to the Venturi jet injector through pipelines. The ozone generator produces ozone gas with a concentration of 4-15 g / m³, which is drawn in by the negative pressure of the Venturi jet injector and mixed with the nutrient solution. The contact time between the nutrient solution and ozone is ≥2 minutes, so that the oxidation-reduction potential (ORP) is maintained at 650-750 mV. After disinfection, the nutrient solution enters the buffer tank and is allowed to stand to degrade the residual ozone until the ORP < 450 mV.
[0029] Step 4: Safe nutrient solution supply: After the nutrient solution has passed the test, it is pumped back to the closed planting trough by a water pump placed in a buffer tank;
[0030] Step 5: Exhaust gas treatment: Residual ozone gas is filtered and catalytically decomposed by activated carbon laid in the planting trough, so that the ozone concentration is <0.05ppm before being discharged through the exhaust port on the buffer tank.
[0031] Step 3: Ozone water circulation disinfection is specifically adjusted dynamically through the ORP sensor. When the ORP sensor detects ORP > 750mV, the output power of the ozone generator is reduced; when ORP < 650mV, the output power of the ozone generator is increased.
[0032] The volume of the buffer tank is configured to be 20%-25% of the total nutrient solution circulation volume, and the residual ozone degradation time is ≤30 minutes.
[0033] The beneficial effects of this utility model are:
[0034] 1. Periodic disinfection strategy: Ozone disinfection is started on the 7th day after transplanting to avoid damage to the sensitive root system during the seedling stage; disinfection is carried out for 30 minutes every 7 days to balance sterilization needs and energy consumption (comparative experiments show that the root hair burn rate decreased from 23% to 0.5%).
[0035] 2. High-efficiency gas-liquid mixing design: The Venturi jet injector uses the pressure difference of the return pressure to draw in ozone, with a dissolution efficiency of over 85%; the gas-liquid contact time in the Venturi jet injector is ≥2 minutes, killing 99.2% of pathogens;
[0036] 3. Safe closed-loop control: The ORP sensor dynamically adjusts the ozone dosage to maintain the optimal sterilization range of 650-750mV; the buffer tank baffle structure ensures that residual ozone is degraded into oxygen (ORP<450mV), avoiding oxidative damage to hydroponic seedlings. Attached Figure Description
[0037] Figure 1 This is a schematic diagram of the connection of the closed hydroponic device for ozone water circulation disinfection according to this utility model. Detailed Implementation
[0038] The present invention will be further described below with reference to the accompanying drawings. All components of this invention, including the enclosed planting trough, ozone generator, pipes, venturi jet injector, buffer tank, water pump, PLC controller, integrated pH sensor, EC sensor and ORP sensor, ORP sensor, flow meter, oxygenation pump, DO sensor and activated carbon, are existing structures and can be purchased directly.
[0039] like Figure 1As shown, this utility model discloses a closed hydroponic device utilizing ozone water circulation for disinfection, comprising a closed planting trough 1, an ozone generator 2, pipes 3, a Venturi jet injector 4, a buffer tank 5, a water pump, a PLC controller, an integrated sensor, an ORP sensor, a flow meter 6, an oxygen pump, and a DO sensor. The integrated sensor integrates a pH sensor, an EC sensor, and an ORP sensor. The closed planting trough 1 has an inlet and an outlet, and activated carbon 7 is laid at the bottom of the closed planting trough 1. The oxygen pump and DO sensor are respectively placed inside the closed planting trough. The water pump is placed inside the buffer tank 5, and the outlet of the closed planting trough 1 is connected to the Venturi jet injector via pipe 3. The venturi jet 4 and the connected buffer tank 5 are connected. The water pump outlet is connected to the liquid inlet of the closed planting trough 1 through pipe 3. The ozone generator 2 outlet is connected to the negative pressure port of the venturi jet 4 through pipe 2. The buffer tank is equipped with a material addition port 51 and an exhaust port 52. The buffer tank 5 is equipped with a baffle plate (not shown in the figure). The integrated sensor is installed in the buffer tank 5, the ORP sensor is installed in the venturi jet 4, and the flow meter 6 is installed on the pipe 3 at the outlet of the ozone generator 2. The PLC controller controls the water pump, the ozone generator 2 and the oxygenation pump respectively. The ORP sensor, the integrated sensor, the flow meter and the DO sensor are connected to the PLC controller respectively.
[0040] A hydroponic method using a closed-loop hydroponic device with ozone water circulation disinfection, characterized by comprising the following steps:
[0041] Step 1: Seedling Transplanting: In a sterile environment, transplant the seedlings onto the planting baskets 11 of the closed planting trough 1. Start the nutrient solution circulation, adjust the pH of the nutrient solution to 6.0-7.0, the conductivity EC to 1.5-2.0 mS / cm, and the dissolved oxygen to 8-10 mg / L; dynamically adjust the dissolved oxygen in the circulating nutrient solution through the DO sensor. When the dissolved oxygen is below 8 mg / L, the PLC controller turns on the oxygenation pump to work; when the dissolved oxygen is above 10 mg / L, the PLC controller turns off the oxygenation pump.
[0042] Step 2: Periodic ozone disinfection: Starting on the 7th day after transplanting, ozone water circulation disinfection is activated for 30 minutes in each 7-day cycle.
[0043] Step 3: Ozone water circulation disinfection: The nutrient solution returning from the closed planting trough 1 is transported to the Venturi jet injector 4 via pipe 3. The ozone generator 2 generates ozone gas with a concentration of 4-15 g / m³, which is drawn in by the negative pressure of the Venturi jet injector 4 and mixed with the nutrient solution. The contact time between the nutrient solution and ozone is ≥2 minutes, so that the oxidation-reduction potential (ORP) is maintained at 650-750 mV. After disinfection, the nutrient solution enters the buffer tank 5 and is allowed to stand to degrade the residual ozone until the ORP < 450 mV. The ORP sensor dynamically adjusts the output power of the ozone generator 2. When the ORP sensor detects ORP > 750 mV, the output power of the ozone generator 2 is reduced, and when ORP < 650 mV, the output power of the ozone generator 2 is increased.
[0044] Step 4: Safe nutrient solution supply: After the nutrient solution passes the test, it is pumped back to the closed planting trough 1 by a water pump placed in the buffer tank 5; the volume of the buffer tank 5 is configured to be 20%-25% of the total circulating volume of the nutrient solution, and the residual ozone degradation time is ≤30 minutes;
[0045] Step 5: Exhaust gas treatment: The residual ozone gas is filtered and catalytically decomposed by the activated carbon 7 laid in the closed planting trough 1, so that the ozone concentration is <0.05ppm and then discharged through the exhaust port on the buffer tank.
[0046] The beneficial effects of this utility model are:
[0047] 1. Sterilization performance: Killing rate of waterborne pathogens (such as Pythium ultimum): 99.2%; Algae growth inhibition rate: 100% (90% reduction compared to traditional systems).
[0048] 2. Crop safety indicators are shown in Table 1.
[0049] Table 1
[0050]
[0051] 3. Economic efficiency: Nutrient solution replacement cycle: 7 days → 21 days; maintenance costs reduced by 40% (no need to replace UV lamps / chemical agents).
[0052] 4. Table 2 compares the implementation effects of this utility model device with those of the traditional UV disinfection system. Except for the different disinfection methods, everything else is the same.
[0053] Table 2
[0054]
[0055] 5. The device using this utility model was designated as experimental group #1, and the other device using a traditional hydroponic system (disinfected with sodium hypochlorite) was designated as control group #2.
[0056] Taking bok choy cultivation as an example:
[0057] Transplanting preparation: After 35 days of seedling cultivation, transplant the seedlings into the planting baskets of the planting trough and inject nutrient solution (pH 6.5, EC 1.8 mS / cm).
[0058] Disinfection phase: Ozone circulation is initiated on the 7th day after transplanting.
[0059] The Venturi jet injects ozone (concentration 10 g / m³), and the ORP of the mixed solution is controlled at 700 ± 10 mV.
[0060] Let the buffer tank stand for 25 minutes until ORP = 420mV;
[0061] Harvesting verification: The growth cycle has ended, and the comparative test data are shown in Table 3 below.
[0062] Table 3:
[0063]
[0064] The data in the table above clearly shows that the experimental group sterilized by ozone using this invention exhibits better growth indicators than the control group in terms of leaf quantity, plant height, root length, sugar content, fresh weight, and dry weight.
[0065] Those skilled in the art will readily understand that the above are merely preferred embodiments of the present utility model and are not intended to limit the present utility model. Any modifications, combinations, substitutions, improvements, etc., made under the spirit and principles of the present utility model are included within the protection scope of the present utility model.
Claims
1. A closed hydroponic device utilizing ozone water circulation for disinfection, comprising a closed planting trough, an ozone generator, pipes, a Venturi jet injector, a buffer tank, a water pump, and a PLC controller, characterized in that, The closed planting trough is equipped with an inlet and an outlet. The water pump is placed in a buffer tank. The outlet of the closed planting trough is connected to the Venturi jet injector and the connected buffer tank in sequence through pipes. The outlet of the water pump is connected to the inlet of the closed planting trough through pipes. The outlet of the ozone generator is connected to the negative pressure port of the Venturi jet injector through pipes. The PLC controller controls the water pump and the ozone generator respectively. The buffer tank is equipped with a material addition port and an exhaust port.
2. The closed hydroponic device for ozone water circulation disinfection according to claim 1, characterized in that, The bottom of the enclosed planting trough is lined with activated carbon.
3. The closed hydroponic device for ozone water circulation disinfection according to claim 1, characterized in that, It also includes an integrated sensor that combines a pH sensor, an EC sensor, and an ORP sensor, an ORP sensor, and a flow meter. The integrated sensor is installed inside the buffer tank, the ORP sensor is installed inside the Venturi jet injector, and the flow meter is installed on the pipe at the outlet of the ozone generator. The pH sensor, EC sensor, ORP sensor, and flow meter in the integrated sensor are all connected to the PLC controller.
4. The closed hydroponic device for ozone water circulation disinfection according to claim 3, characterized in that, It also includes an oxygenation pump and a DO sensor, which are placed in a closed planting trough. The DO sensor is connected to a PLC controller, which in turn controls the oxygenation pump.
5. The closed hydroponic device for ozone water circulation disinfection according to claim 3, characterized in that, The buffer tank is equipped with baffles.