CN112266273B

CN112266273B - Method and system for in-situ synthesis and application of plant nitrogen fertilizer

Info

Publication number: CN112266273B
Application number: CN202011181597.6A
Authority: CN
Inventors: 鲜于斌; 周德江
Original assignee: Huazhong University of Science and Technology
Current assignee: Huazhong University of Science and Technology
Priority date: 2020-10-29
Filing date: 2020-10-29
Publication date: 2021-12-31
Anticipated expiration: 2040-10-29
Also published as: CN112266273A

Abstract

The invention belongs to the field of plant fertilization, and particularly discloses a method and a system for in-situ synthesis and application of a plant nitrogen fertilizer, wherein the method comprises the following steps: on one side of the plant, storing and boosting the output electric energy of the solar cell, applying the obtained high voltage to the electrode, and puncturing air under the action of a strong electric field to form discharge plasma; the plasma reacts with nitrogen and oxygen in the air and water released to the reaction tank from the water storage tank to generate nitrogen fertilizer and release the nitrogen fertilizer to the roots of the plants. The invention utilizes solar energy, air and water as raw materials, adopts a plasma nitrogen fixation technology to generate a nitrogen-containing aqueous solution, and directly applies the nitrogen-containing aqueous solution to plant roots, and is a technology which generates the nitrogen-containing aqueous solution by using the plasma nitrogen fixation function near plant plants and applies the nitrogen-containing aqueous solution to the plant roots on site. Convenient and fast, saves energy and has low cost, thus being an environment-friendly fertilizing method.

Description

Method and system for in-situ synthesis and application of plant nitrogen fertilizer

Technical Field

The invention belongs to the field of plant fertilization, and particularly relates to a method and a system for in-situ synthesis and application of a plant nitrogen fertilizer.

Background

Nitrogen fixation refers to the conversion of free nitrogen in the air into nitrogen-containing substances, such as ammonia, nitrogen oxides, nitrates, and the like. For plants, nitrogen fertilizers such as nitrate are essential nutrients for healthy growth of the plants, but the plants cannot directly utilize nitrogen in the air to synthesize nitrogen-containing compounds required by the plants. Therefore, people have to apply nitrogen fertilizer to plants (crops) periodically to ensure their normal growth. For modern agriculture, nitrogen fertilizer is an indispensable basic fertilizer, and the annual use amount is extremely large. The price of nitrogen fertilizer even directly affects the price of food.

However, the use of nitrogen fertilizers on a large scale presents a series of problems. On the one hand, each link of nitrogen fertilizer production consumes a large amount of energy, and only one item of synthetic ammonia consumes 2% of the total energy consumed worldwide each year. Meanwhile, the fertilizer production industry also discharges a large amount of greenhouse gases and harmful gases such as carbon dioxide. Wherein the greenhouse gas emission of the synthetic ammonia industry accounts for about 1.0 percent of the global greenhouse gas emission (accounts for about 1.4 percent of the global carbon dioxide emission). Meanwhile, the regular application of nitrogen fertilizer also increases the workload of agricultural workers and the agricultural production cost, and increases the food price.

Disclosure of Invention

The invention provides a method and a system for in-situ synthesis and application of a plant nitrogen fertilizer, which are used for solving the technical problem of high application cost of the existing plant nitrogen fertilizer.

The technical scheme for solving the technical problems is as follows: a method for in-situ synthesis and application of plant nitrogen fertilizer, comprising:

on one side of the plant, boosting the output electric energy of the solar cell, applying the obtained high voltage to the electrode, and puncturing air under the action of a strong electric field to form discharge plasma; the plasma reacts with nitrogen and oxygen in the air and water released to the reaction tank from the water storage tank to generate nitrogen fertilizer and release the nitrogen fertilizer to the roots of the plants.

The invention has the beneficial effects that: the method is characterized in that solar energy, air and water are used as raw materials, a nitrogen-containing aqueous solution is generated by adopting a plasma nitrogen fixation technology and is directly applied to plant roots, and the method is a technology for generating the nitrogen-containing aqueous solution by utilizing the plasma nitrogen fixation function near plant plants and applying the nitrogen-containing aqueous solution to the plant roots on site. Convenient transboundary, energy saving and low cost, and is an environment-friendly fertilizing method.

On the basis of the technical scheme, the invention can be further improved as follows.

Further, the water in the water storage tank is rainwater.

The invention has the further beneficial effects that: the cost is reduced and the energy is saved.

Further, a control circuit is adopted to control the solar battery to output electric energy and boost the voltage.

Further, the method further comprises: monitoring the liquid level in the water storage tank in real time, and controlling the water in the water storage tank to flow to the reaction tank when the liquid level is detected to be higher than a threshold value;

wherein the threshold is set according to weather and land fertility.

The invention has the further beneficial effects that: through the liquid level height of control water storage tank, give and make the water among the water storage tank to the triggering adjustment of reaction tank, also be convenient for remote control operation.

The invention also provides a system for in-situ synthesis and application of a plant nitrogen fertilizer, which is arranged on one side of a plant and comprises: the device comprises a solar cell, a storage battery, a high-voltage module, a high-voltage discharge electrode, a high-voltage-resistant insulated wire, a reaction tank, a water storage tank and a fertilizing conduit;

the solar cell outputs electric energy to the storage battery to charge the storage battery, the storage battery outputs electric energy to the high-voltage module, the high-voltage module boosts the electric energy and applies the obtained high voltage to the high-voltage discharge electrode, wherein one end of the high-voltage-resistant insulating wire is connected with the negative electrode of the high-voltage module, the other end of the high-voltage-resistant insulating wire is grounded, and the high-voltage discharge electrode breaks through air under the action of a strong electric field to form discharge plasma; the plasma reacts with nitrogen and oxygen in the air and water released to the reaction tank from the water storage tank to generate nitrogen fertilizer and the nitrogen fertilizer is released to the roots of the plants through the fertilizing conduit.

The invention has the beneficial effects that: a miniature portable unsupervised plasma nitrogen fixation device is constructed by utilizing a solar cell, a plasma generation module and air and water in the natural environment, is placed near plants, can collect and store rainwater, converts sunlight into electric energy to drive the plasma, synthesizes a nitrogen-containing aqueous solution through the action of the plasma, the water and the nitrogen and the oxygen in the air, slowly releases the nitrogen-containing aqueous solution to the roots of the plants immediately after synthesizing the aqueous solution, applies nitrogen fertilizer and water to a single plant or a plurality of plants in a small range, and is a portable unsupervised system which is placed near the plants of the plants.

Furthermore, a control circuit is arranged between the storage battery and the high-voltage module, and the control circuit is used for detecting and setting the starting threshold of the high-voltage module according to the water amount in the water storage tank, the electric quantity of the storage battery, the air temperature, the soil humidity and the soil fertility; the control circuit also sets the discharge time and the discharge voltage of the high-voltage module after being started and the water outlet speed of the water storage tank to the reaction tank according to a remote instruction.

Further, the rainwater collecting device is also included; the rainwater collector collects rainwater and provides water to the water storage tank through the one-way valve.

Further, the system also comprises a liquid level control unit which is used for monitoring the liquid level in the water storage tank in real time and controlling the water in the water storage tank to flow to the reaction tank when the liquid level is detected to be higher than a threshold value;

wherein the threshold is set according to weather and land fertility.

Drawings

FIG. 1 is a flow chart of a method for in-situ synthesis and application of a plant nitrogen fertilizer provided by an embodiment of the invention;

FIG. 2 is a schematic diagram of a system for in-situ synthesis and application of a plant nitrogen fertilizer provided by an embodiment of the present invention;

fig. 3 is a flow chart of a fertilizing method corresponding to fig. 2.

The same reference numbers will be used throughout the drawings to refer to the same or like elements or structures, wherein:

1 is the low pressure part, 2 is the high voltage module, 3 is the high voltage discharge electrode, 4 is air discharge plasma, 5 is the reaction tank, 6 is resistant high voltage insulation line, 7 is insulating casing, 8 is the boost switch, 9 is the rainwater collector, 10 is the check valve, 11 is the water storage tank, 12 is the pipe of fertilizeing, 13 is the fertilization valve.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention. In addition, the technical features involved in the embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

Example one

A method 100 for in situ synthesis and application of plant nitrogen fertilizer, as shown in figure 1, comprising:

s110, boosting the output electric energy of the solar cell on one side of the plant, applying the obtained high voltage to an electrode, and puncturing air under the action of a strong electric field to form discharge plasma;

and S120, reacting the plasma with nitrogen and oxygen in the air and water released to the reaction tank from the water storage tank to generate a nitrogen fertilizer and releasing the nitrogen fertilizer to the roots of the plants.

The plasma is a fourth substance form except solid, liquid and gas, is an active particle aggregate which is electrically neutral as a whole and has unique physical and chemical properties. With the deep research on the plasma theory and the development of the plasma technology, the plasma has great application value in many aspects, including the application of plasma nitrogen fixation. The nitrogen structure has stable nitrogen-nitrogen triple bonds, so that the nitrogen has low reaction activity, high energy barrier for participating in the reaction and difficult reaction. And high-energy electrons in the plasma can interact with gas molecules to convert particles into an excited state, and even chemical bonds can be broken to convert the particles into highly activated free radicals, so that the reaction which is difficult to spontaneously proceed or even cannot occur is performed. Therefore, the plasma can fix nitrogen at normal temperature and normal pressure by using electric energy, air and water to convert nitrogen into ammonia, nitric oxide and nitrogen dioxide. These small nitrogen-containing molecules are very soluble in water to form nitrite ions, nitrate ions, and ammonium ions. The water solution containing these ions is a good nitrogen fertilizer and can be directly absorbed by plant root system. Meanwhile, the plasma nitrogen fixation only needs air, water and electric energy. Wherein both air and water are widely present in nature. And the electric energy can be generated by a solar cell. Therefore, the plasma technology can automatically utilize sunlight, air and water to synthesize nitrogen fertilizer under the condition of no manual intervention.

The method utilizes the solar cell to convert sunlight into electric energy; storing electrical energy using a rechargeable battery; converting low-voltage electric energy provided by the battery into high voltage by using the boosting module; high voltage is applied to the electrode, and air near the electrode is broken down under the action of a strong electric field to form discharge plasma; the plasma reacts with nitrogen and oxygen in the air and water slowly released from a water storage tank to generate an aqueous solution containing nitrate ions, nitrite ions and ammonium ions; the aqueous solution containing nitrogen is released to the roots of the plant through a catheter.

The method is a method which uses solar energy, air and water as raw materials, adopts a plasma nitrogen fixation technology to generate a nitrogen-containing water solution and directly applies the nitrogen-containing water solution to plant roots. Specifically, according to the method, a miniature portable unsupervised plasma nitrogen fixation device can be constructed by utilizing a solar cell, a plasma generation module and air and water in the natural environment, the miniature portable unsupervised plasma nitrogen fixation device is placed near the plants, rainwater can be collected and stored, sunlight is converted into electric energy to drive the plasma, nitrogen-containing aqueous solution is synthesized through the action of the plasma, the water and nitrogen and oxygen in the air, and the nitrogen-containing aqueous solution is immediately and slowly released to the roots of the plants after being synthesized to apply nitrogen fertilizer and water to a single plant or a plurality of plants in a small range. A portable, unsupervised means of being placed in proximity to plant plants.

It is noted that there are two ways for synthesizing nitrogen fertilizer, one is that air plasma utilizes nitrogen element in air to produce NO and NO₂The plasma is dissolved in water, and the other is formed by nitrate formed by the plasma and nitrogen elements in water and air.

Preferably, the water in the water storage tank is rainwater. The cost is reduced and the energy is saved.

Preferably, a control circuit is used to control the battery to output electric energy and boost the voltage. Can be controlled remotely or in the field.

Specifically, the control circuit can be used for detecting and setting the starting threshold of the high-voltage module according to the water amount in the water storage tank, the electric quantity of the storage battery, the air temperature, the soil humidity and the soil fertility; the control circuit also sets the discharge time and the discharge voltage of the high-voltage module after being started and the water outlet speed of the water storage tank to the reaction tank according to the remote instruction, and the whole process does not need manual intervention so as to realize automation.

Preferably, the method further comprises: monitoring the liquid level in the water storage tank in real time, and controlling the water in the water storage tank to flow to the reaction tank when the liquid level is detected to be higher than a threshold value; wherein the threshold value is set according to weather and land fertility.

The method reasonably utilizes solar energy, and reduces the emission of greenhouse gases and harmful gases in the traditional nitrogen fertilizer synthesis process. Reduces energy consumption, and avoids the fixed asset investment and the operation cost in the traditional nitrogen fertilizer production and transportation process. The degree of automation of agricultural production is improved, the working procedures of agricultural production are greatly reduced, and the improvement of the agricultural production efficiency is facilitated. By applying nitrogen fertilizer and water directly to the roots of the plants, the utilization efficiency of the fertilizer and water is improved. The expandability is strong, a soil property detection sensor can be further introduced subsequently, different operation parameters are automatically set for different soil environments, more refined conditions are realized, and the refined degree of agricultural management is improved.

Example two

A plant nitrogen fertilizer in-situ synthesis and application system is arranged on one side of a plant and comprises: the device comprises a solar cell, a high-voltage module, a high-voltage discharge electrode, a high-voltage-resistant insulated wire, a reaction tank, a water storage tank and a fertilizing conduit;

the solar cell outputs electric energy to the high-voltage module, the high-voltage module boosts the electric energy and applies the obtained high voltage to the high-voltage discharge electrode, wherein one end of the high-voltage resistant insulating wire is connected with the negative electrode of the high-voltage module, the other end of the high-voltage resistant insulating wire is grounded, and the high-voltage discharge electrode punctures air under the action of a strong electric field to form discharge plasma; the plasma reacts with nitrogen and oxygen in the air and water released to the reaction tank by the water storage tank to generate nitrogen fertilizer which is released to the roots of the plants through the fertilizing conduit.

Preferably, a control circuit is arranged between the storage battery and the high-voltage module, and the control circuit is used for detecting and setting the starting threshold of the high-voltage module according to the water quantity in the water storage tank, the electric quantity of the storage battery, the air temperature, the soil humidity and the soil fertility without manual intervention; the control circuit can also carry out remote communication, and the discharge time and the discharge voltage after the high-voltage module is started and the water outlet speed of the water storage tank to the reaction tank are set according to a remote instruction.

Preferably, the device further comprises a rain water collector; the rainwater collector collects rainwater and provides water source for the water storage tank through the one-way valve.

Fig. 2 shows a schematic structure of the device of the embodiment, which comprises: 1. a low voltage part including a solar cell and a rechargeable battery; 2. the high-voltage module is used for boosting low voltage so as to achieve the purpose of discharging, and can be a direct-current boosting module, an inversion alternating-current boosting module, a pulse high-voltage generating module and an arbitrary waveform high-voltage generating module; 3. the high-voltage discharge electrode can be made of conductive metal such as steel, copper, aluminum and the like, the surface of the high-voltage discharge electrode can be coated with a catalyst, and the high-voltage discharge electrode can be in a needle-shaped, rod-shaped, plate-shaped or other discharge structure; 4. an air discharge plasma; 5. the reaction tank is of a tank type or a dish type, adopts glass or a corrosion-resistant high polymer material, does not use a metal material, and the nitrate solution can corrode metal; 6. one section of the high-voltage resistant insulated wire is connected with the negative electrode of the high-voltage module, and the other end of the high-voltage resistant insulated wire is placed in the solution of the container; 7. an insulating housing, which may be a plastic or the like; 8. the boosting switch is arranged between the low-voltage module and the high-voltage module, controls the working state of the device and can adopt a mechanical switch or a remote wireless control switch; 9. a rainwater collector for collecting rainwater; 10. the one-way valve is used for sealing the water storage tank below to prevent water from evaporating; 11. the water storage tank is used for storing the collected rainwater and slowly releasing the rainwater into the reaction tank 5; 12. a fertilizing conduit for guiding the nitrogen-containing aqueous solution generated by the plasma treatment to the root of the plant, and a fertilizing valve 13 for controlling the nitrogen fertilizer produced in the reaction tank to flow to the plant.

As shown in fig. 3, a certain amount of water (tap water or rain water) is first filled in a container (i.e. a reaction tank) at the bottom end of the device, one end of an insulated wire connected with a high-voltage negative electrode is extended into the solution, then a switch is pressed (boosted), plasma is generated by air discharge, a plasma nitrogen fixation process is carried out, and the obtained solution contains substances such as nitrate and the like and can be directly used for fertilization. If the switch adopts a remote control mode, the operation of the device can be controlled according to a remote instruction.

It should be noted that there are a total of three valves in the system: a boost switch of the control circuit; a valve for controlling the water outlet of the water storage tank; a valve for controlling the synthetic liquid in the reaction vessel to flow to the plants. The specific matching mode can be as follows: the valve of the water storage tank is opened, water flows into the reaction vessel, then the circuit switch is closed to generate plasma, the plasma reacts with the water to synthesize nitrogen fertilizer, finally, the valve arranged on the reaction vessel is opened, and the liquid containing the nitrogen fertilizer flows to plants or land.

In addition, the installation mode of the system in the real scene is set according to the actual use scene. For example, when the plant is large, the device can be miniaturized, and each plant is provided with a system; for another example, when the plant is small, a large device can be customized and a system can be arranged in a region.

Preferably, the system further comprises a liquid level control unit for monitoring the liquid level in the water storage tank in real time, and controlling the water in the water storage tank to flow to the reaction tank when the liquid level is detected to be higher than a threshold value; wherein the threshold value is set according to weather and land fertility.

It will be understood by those skilled in the art that the foregoing is only a preferred embodiment of the present invention, and is not intended to limit the invention, and that any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the scope of the present invention.

Claims

1. A plant nitrogen fertilizer in-situ synthesis and application system is characterized by being arranged on one side of a plant and comprising: the device comprises a solar cell, a storage battery, a high-voltage module, a high-voltage discharge electrode, a high-voltage-resistant insulated wire, a reaction tank, a water storage tank and a fertilizing conduit; the rainwater collecting device is also included; the rainwater collector collects rainwater and provides water source for the water storage tank through the one-way valve;

the solar cell outputs electric energy to the storage battery to charge the storage battery, the storage battery outputs electric energy to the high-voltage module, the high-voltage module boosts the electric energy and applies the obtained high voltage to the high-voltage discharge electrode, wherein one end of the high-voltage-resistant insulating wire is connected with the negative electrode of the high-voltage module, the other end of the high-voltage-resistant insulating wire is grounded, and the high-voltage discharge electrode punctures air under the action of a strong electric field to form discharge plasma; the plasma reacts with nitrogen and oxygen in the air and water released to the reaction tank by the water storage tank to generate nitrogen fertilizer and the nitrogen fertilizer is released to the roots of the plants through the fertilizing conduit; the mode of synthesizing the nitrogen fertilizer is as follows: the plasma utilizes electric energy, air and water to fix nitrogen, converts nitrogen into ammonia gas, nitric oxide and nitrogen dioxide, and dissolves the ammonia gas, the nitric oxide and the nitrogen dioxide in water to form nitrite ions, nitrate ions and ammonium ions;

the system automatically utilizes sunlight, air and water to synthesize nitrogen fertilizer under the condition of no manual intervention and directly applies the nitrogen fertilizer to plant roots, and is a miniature portable unsupervised plant nitrogen fertilizer in-situ synthesis and application system which is arranged near plant plants.

2. The system for in-situ synthesis and application of plant nitrogen fertilizer as claimed in claim 1, wherein a control circuit is arranged between the storage battery and the high voltage module, the control circuit is used for detecting and setting the starting threshold of the high voltage module according to the water amount in the water storage tank, the electric quantity of the storage battery, the air temperature, the soil humidity and the soil fertility; the control circuit also sets the discharge time and the discharge voltage of the high-voltage module after being started and the water outlet speed of the water storage tank to the reaction tank according to a remote instruction.

3. The system for in-situ synthesis and application of plant nitrogen fertilizer as claimed in claim 1, further comprising a liquid level control unit for monitoring the liquid level in the water storage tank in real time, and controlling the water in the water storage tank to flow to the reaction tank when the detected liquid level is higher than a threshold value;

wherein the threshold is set according to weather and land fertility.