Waste gas treatment equipment with fundamental wave and narrow pulse superposition power supply

Abstract

The invention discloses waste gas treatment equipment with a fundamental wave and narrow pulse superposition power supply, and relates to the technical field of waste gas treatment. The problems that in the prior art, when waste gas is treated through plasmas, the organic waste gas treatment efficiency of aromatic compounds is low, many harmful intermediate by-products can be generated, and a large amount of ozone escapes are solved. The equipment comprises a shell with a channel, a plasma generation module, a spraying assembly and a power supply module used for providing a fundamental wave unit and a narrow pulse unit for a discharge electrode wire, and the narrow pulse unit is superposed on the basis of the fundamental wave unit to serve as a power supply of the plasma generation module. The concentration of treatable pollutants is improved, the energy consumption of equipment is reduced, the treatment efficiency of waste gas is improved, the reaction of the waste gas is more thorough, and the problem of ozone overflow is solved.

Description

Technical Field

[0001] The present application relates to the technical field of waste gas treatment, and in particular to a waste gas treatment device having a fundamental wave and narrow pulse superimposed power supply. Background Art

[0002] Low-temperature plasma is the fourth state of matter after solid, liquid and gas. When the applied voltage reaches the ignition voltage of the gas, the gas is broken down to produce a mixture of electrons, various ions, atoms and free radicals. Although the electron temperature is very high during the discharge process, the temperature of heavy particles is very low, and the entire system is in a low-temperature state, so it is called low-temperature plasma. Low-temperature plasma degradation of pollutants is to use these electrons, free radicals and other active particles to interact with pollutants in the exhaust gas, so that the pollutant molecules are decomposed within a certain period of time, and various subsequent reactions occur to achieve the purpose of decomposing pollutants.

[0003] As a new type of gaseous pollutant treatment technology, low-temperature plasma industrial waste gas treatment equipment and technology is an interdisciplinary comprehensive electronic chemical technology that integrates physics, chemistry, biology and environment. It is one of the most promising technical methods in air pollution control because it can easily decompose pollutant molecules and has low treatment energy consumption. It has broad prospects for use and promotion, and has opened up a new idea for the treatment of industrial formaldehyde waste gas and odorous gases.

[0004] However, the current process and equipment, plasma technology has a very low efficiency in treating organic waste gas including aromatic compounds in a short period of time, mainly generating intermediate products. If high-power plasma is used in stable organic waste gas, it will take a certain period of time to achieve the treatment effect. For the VOCs waste gas discharged continuously and at a high speed by industrial production, its treatment efficiency is very low and many intermediate by-products will be generated, resulting in a more complex VOCs composition (these by-products may be more harmful), and a large amount of useless ozone will be generated when the equipment is running.

[0005] The combination of low-temperature plasma and catalyst has become one of the hot spots in the treatment of VOCs-containing and odorous waste gas. However, the water vapor in the waste gas (or the water vapor generated during the degradation of VOCs) will affect the performance of the catalyst. At the same time, the intermediate polymers produced during the degradation process will be adsorbed and deposited on the surface of the catalyst, reducing the probability of its surface reacting with VOCs molecules, thereby reducing the activity and stability of the catalyst, and even causing the catalyst to deactivate. The need to constantly replace the catalyst will bring inconvenience to industrial production and increase costs.

[0006] In narrow plasma technology, an important method of generating plasma is through narrow pulse discharge. Narrow pulse discharge is a discharge process that uses capacitor charging and discharging to form a pulse current and generate high energy in a short time. The principle is to charge the capacitor so that the capacitor stores the charge and release the charge at the right time to form a current pulse with high voltage, high current and high temperature.

[0007] Narrow pulse discharge has a very short rising edge of nanosecond pulse voltage, a very narrow pulse width, and very small single pulse energy during discharge. This can avoid arc discharge and excessive Joule heat, and has high energy utilization efficiency. This technology can react efficiently with organic molecular bonds at room temperature, and no external reagents need to be added during the process.

[0008] In narrow pulse discharge, the effective discharge time refers to the pulse width, that is, the time period during which the discharge actually occurs. In contrast, the ineffective part is usually called the "interval" or "non-discharge time". No actual discharge occurs during this period, so no plasma or arc is generated. Since the duty cycle of narrow pulse discharge is low, the corresponding non-discharge time (i.e., pulse interval) is longer. In the narrow pulse discharge process, oxygen molecules are the main reactants. When oxygen molecules obtain energy from free electrons, excited oxygen is formed. These excited oxygens further react with oxygen molecules to generate ozone. Ozone itself has strong oxidizing properties and can decompose harmful gas molecules such as VOCs (volatile organic compounds), CO, SO2, etc. Therefore, the generation of ozone also enhances the gas purification effect to a certain extent. However, too much ozone may also have an adverse effect on the environment. Therefore, when treating exhaust gas with narrow pulse discharge equipment, it is necessary to remove excess ozone to prevent ozone from escaping into the environment. Summary of the invention

[0009] The purpose of this application is to overcome the problems in the prior art of using plasma to treat organic waste gas containing aromatic compounds, which has low efficiency, produces many harmful intermediate by-products, and has a large amount of ozone escape, and to provide a waste gas treatment device with a fundamental wave and narrow pulse superimposed power supply.

[0010] In a first aspect, an exhaust gas treatment device having a fundamental wave and a narrow pulse superposition power supply is provided, comprising:

[0011] A housing, wherein the housing has a channel, one end of the channel is provided with an air inlet, and the other end of the channel is provided with an air outlet;

[0012] A plasma generating module, the plasma generating module comprising an upper bracket, a lower bracket and a discharge electrode wire, the upper bracket and the lower bracket are installed in the channel at a distance, and a plurality of discharge electrode wires are installed between the upper bracket and the lower bracket;

[0013] A spray assembly, wherein the spray assembly is used to remove attachments on the plasma generating module;

[0014] A power supply module is used to provide a superimposed power supply of a fundamental wave unit and a narrow pulse unit to the discharge electrode line, wherein the fundamental wave unit is a DC high-voltage power supply and the narrow pulse unit is a nanosecond pulse high-voltage power supply.

[0015] In some possible implementations, the discharge electrode includes a connecting rod, the outer wall of the connecting rod is sleeved with multiple cylinders, one end of the cylinder is integrally formed with multiple discharge plates, the discharge plates are arranged as a polygonal structure, and a specified angle is reserved between the discharge plates and the end face of the cylinder, and the specified angle is 68°-85°. A plurality of limiting grooves are reserved at one end of the cylinder, and a limiting protrusion adapted to the limiting groove is reserved at the other end of the cylinder. The length of the cylinder is 35mm-40mm, and the rotation angle between adjacent cylinders is 11.25°-45°.

[0016] In some possible implementations, the ratio of the discharge frequency of the narrow pulse unit and the fundamental wave unit in the superimposed power supply is 1:18-24.

[0017] In some possible implementations, the electric field strength provided by the narrow pulse unit is greater than 5000 V / cm, and the electric field strength provided by the fundamental wave unit is 2000-3800 V / cm.

[0018] In some possible implementations, a water receiving tray is provided below the plasma generating module, the water receiving tray is connected to a water tank via a water inlet pipe, the water inlet pipe is equipped with a first valve, the water tank is also connected to a drain pipe, the drain pipe is equipped with a second valve, and wastewater collected in the water tank can be discharged by opening the second valve.

[0019] In some possible implementations, a PLC controller is further included, the power module is electrically connected to the PLC controller, and the PLC controller is used to control whether the power module supplies power to the discharge pole line, as well as the output power of the pulse power supply and the fundamental wave unit.

[0020] In some possible implementations, a third valve is installed in the water supply pipe of the spray assembly, the first valve and the third valve are both solenoid valves, and the control ends of the first valve and the third valve are both electrically connected to the PLC controller.

[0021] In some possible implementations, the air inlet is installed with a gas detector for detecting pollutant concentration, and the air outlet is installed with an ozone detector, and both the gas detector and the ozone detector are electrically connected to the PLC controller.

[0022] In some possible implementations, a buffer material for slowing down the flow rate of the gas is filled in a region in the channel between the gas outlet and the plasma generating module.

[0023] In some possible implementations, the air inlet is provided with a filter component.

[0024] This application has the following beneficial effects:

[0025] 1. This application superimposes a narrow pulse unit on the fundamental wave unit as the power source of the plasma generating module. Compared with the pulse power source, it not only increases the concentration of the pollutants that can be treated, but also reduces the energy consumption of the equipment, improves the waste gas treatment efficiency, makes the waste gas reaction more thorough, solves the problem of ozone overflow, and can effectively remove dust and droplets in the gas during the action of the fundamental wave unit, thereby preventing the odor from escaping in the droplets;

[0026] 2. The discharge sheet of the present application has a certain angle with the end surface of the column, and the overall shape is a flower. The gas rotates continuously in the reaction zone, which increases the path and reaction time of the gas in the reaction zone, which is beneficial to increase the treatment efficiency of the exhaust gas. In addition, the discharge sheet is a polygon, and the edge of the discharge sheet is a smooth straight line, which is conducive to uniform discharge. Secondly, the discharge electrode has high mechanical strength, is easy to transport, more durable, and easy to replace. The length of the electrode can be adjusted at will according to needs, and the column can be recycled. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The drawings constituting a part of the present application are used to provide a further understanding of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application.

[0028] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0029] Figure 1 It is a structural schematic diagram of an exhaust gas treatment device with a fundamental wave and narrow pulse superposition power supply according to an embodiment of the present application;

[0030] Figure 2 is a cross-sectional view of a shell in an exhaust gas treatment device having a fundamental wave and narrow pulse superposition power supply according to an embodiment of the present application;

[0031] Figure 3 is a cross-sectional view of an exhaust gas treatment device having a fundamental wave and narrow pulse superposition power supply according to an embodiment of the present application;

[0032] Figure 4 It is a schematic diagram of the structure of a spray assembly in an exhaust gas treatment device having a fundamental wave and a narrow pulse superposition power supply according to an embodiment of the present application;

[0033] Figure 5 It is a schematic diagram of the structure of the discharge electrode wire in the exhaust gas treatment equipment with a fundamental wave and narrow pulse superposition power supply in an embodiment of the present application;

[0034] Figure 6 It is a structural schematic diagram of a column and a discharge plate in an exhaust gas treatment device having a fundamental wave and a narrow pulse superposition power supply according to an embodiment of the present application;

[0035] Figure 7 It is an exploded view of the discharge electrode wire in the exhaust gas treatment device with a fundamental wave and narrow pulse superposition power supply according to an embodiment of the present application;

[0036] Figure 8 It is a schematic diagram of the discharge cross section when the discharge electrode wire is used in the exhaust gas treatment equipment with a fundamental wave and narrow pulse superposition power supply in the embodiment of the present application;

[0037] Fig. 9 It is a schematic diagram of the structure of the discharge electrode wire in which each column has four discharge plates in the exhaust gas treatment equipment with a fundamental wave and narrow pulse superposition power supply according to an embodiment of the present application;

[0038] Fig.10 It is a schematic diagram of the structure of the discharge electrode wire in which each column has sixteen discharge plates in the exhaust gas treatment equipment with a fundamental wave and narrow pulse superposition power supply according to an embodiment of the present application;

[0039] Fig.11 It is a schematic block diagram of the connection of a PLC controller in an exhaust gas treatment device having a fundamental wave and narrow pulse superposition power supply according to an embodiment of the present application;

[0040] Fig.12 It is a schematic diagram of adjusting the narrow pulse discharge frequency by a PLC controller in an exhaust gas treatment device having a fundamental wave and narrow pulse superposition power supply according to an embodiment of the present application;

[0041] Fig.13 It is a schematic diagram of the PLC controller in the exhaust gas treatment equipment with fundamental wave and narrow pulse superposition power supply in the embodiment of the present application turning on the spraying;

[0042] Fig.14 It is a circuit schematic diagram of a power module in an exhaust gas treatment device having a fundamental wave and narrow pulse superposition power supply according to an embodiment of the present application;

[0043] Fig.15 This is an output waveform diagram of a power module in an exhaust gas treatment device having a fundamental wave and narrow pulse superposition power supply according to an embodiment of the present application;

[0044] Fig.16This is a waveform diagram of the output of a nanosecond pulse high-voltage circuit in a power module of an exhaust gas treatment device having a fundamental wave and narrow pulse superposition power supply in an embodiment of the present application;

[0045] Fig.17 It is a comparison diagram of the DC high voltage superimposed nanosecond pulse high voltage output waveform and the DC high voltage output waveform of the power module in the exhaust gas treatment device with a fundamental wave and narrow pulse superimposed power supply in an embodiment of the present application;

[0046] Fig.18 This is a comparison chart of the exhaust gas treatment effects of the same equipment using different power supplies under the same working conditions.

[0047] Reference numerals:

[0048] 100, shell; 101, channel; 102, air inlet; 103, air outlet; 200, plasma generating module; 201, upper bracket; 202, lower bracket; 203, discharge electrode; 2031, connecting rod; 2032, column; 2033, discharge plate; 2034, limiting groove; 2035, limiting protrusion; 300, spray assembly; 301, water supply pipe; 302, nozzle; 303, water tray; 304, water inlet pipe; 305, water tank; 306, first valve; 307, drain pipe; 308, second valve; 309, third valve; 400, power module; 401, fundamental wave unit; 402, narrow pulse unit; 500, PLC controller; 600, gas detector; 700, ozone detector; 800, buffer material; 900, filter assembly. DETAILED DESCRIPTION

[0049] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0050] Example

[0051] like Figure 1-Figure 3As shown, an exhaust gas treatment device with a fundamental wave and a narrow pulse superimposed power supply involved in an embodiment of the present application includes a shell 100, a hollow cut in the shell 100 forms a channel 101, the channel 101 is in a "U" shape, one end of the channel 101 is an air inlet 102, in order to filter the gas entering the channel 101 and perform pre-treatment such as filtering, a filter component 900 is arranged at the air inlet 102, wherein the filter component 900 can be a filter screen, activated carbon, etc., for filtering out large particles in the gas, the other end of the channel 101 is an air outlet 103, and the end of the channel 101 close to the air inlet 102 is a reaction zone, and a plasma generating module 200 is installed in the reaction zone, and the plasma generating module 200 includes an upper bracket 201, a lower bracket 202 and a discharge electrode Line 203, wherein the upper bracket 201 and the lower bracket are fixedly connected to the side wall of the shell 100, and the connection method can be a detachable fixing method such as screws or bolts. A spacing for installing the discharge electrode line 203 is reserved between the upper bracket 201 and the lower bracket 202, and the discharge electrode line 203 is detachably installed between the upper bracket 201 and the lower bracket 202. One end of the channel 101 close to the air outlet 103 is filled with a buffer zone for slowing down the gas flow rate. The buffer zone is filled with buffer materials 800 such as glass fiber, activated carbon particles, ceramic fillers, plastic fillers, metal fillers and composite fillers. When the exhaust gas enters the reaction zone, under the action of the high-voltage electric field, high-energy electrons collide with gas molecules to generate a large number of active particles, such as free radicals, ions, excited state molecules, etc. These active particles have high chemical reactivity and can undergo redox reactions with waste gas molecules, open the chemical bonds of odor molecules, and convert them into small molecules such as carbon dioxide and water. At the same time, they reduce the power of the equipment to control the ozone produced by the previous decomposition reaction. Finally, the gas mass enters the buffer zone, increasing the residence time and making the reaction more sufficient and complete.

[0052] like Figure 5-Figure 7As shown, the discharge electrode line 203 adopts modularization, and the discharge electrode line 203 includes a connecting rod 2031, a column 2032 and a discharge sheet 2033, wherein both ends of the connecting rod 2031 are processed with external threads for connecting the upper bracket 201 and the lower bracket 202, and the middle part of the column 2032 is reserved with a through hole through which the connecting rod 2031 can pass, and the outer wall of the connecting rod 2031 is sleeved with multiple columns 2032, and one end of the column 2032 is integrally formed with multiple discharge sheets 2033, and the discharge sheet 2033 is set to a polygonal structure, such as: quadrilateral, pentagon, octagon, hexadecagon, etc., and a specified angle ɑ is reserved between the discharge sheet and the end face of the column 2032, wherein 68°≤ɑ≤85°, and a plurality of limit grooves 2034 are reserved at one end of the column 2032, and a limit groove 2034 is reserved at the other end of the column 2032. 34 is adapted to the limiting protrusion 2035. After the columns 2032 are successively sleeved on the connecting rod 2031, the limiting protrusions 2035 of the two connected columns 2032 can be inserted into the limiting groove 2034 of the other column 2032. By fixing one of the columns 2032, the effect of fixing all the columns 2032 on the connecting rod 2031 can be achieved, so that the column 2032 will not rotate relative to the connecting rod 2031. The length of the column 2032 is 35mm-40mm, and the rotation angle between adjacent columns 2032 is 11.25°-45°, that is, taking one of the columns 2032 as a reference, the column 2032 adjacent to it rotates 11.25°-45° relative to the reference column 2032 along the axis of the connecting rod 2031 (specifically depending on the number of square electric sheets). The edge of the discharge plate 2033 is a smooth straight line, which is conducive to uniform discharge. The number of discharge plates 2033 on each column 2032 can be customized according to needs, such as Figure 5-Figure 7 As shown, each column 2032 has eight discharge plates 2033 on the discharge electrode line 2033. The discharge cross section of the discharge electrode line 203 when in use is as follows: Figure 8 As shown, Fig. 9 As shown, each column 2032 has four discharge plates 2033 on the discharge electrode line 203, as shown in FIG. Fig.10 As shown, each column 2032 has a discharge electrode line 203 with sixteen discharge plates 2033 .

[0053] In this embodiment, the entire discharge sheet 2033 is in the shape of a flower. It can be fixed in position and can also serve as the main discharge component of the reaction zone. The small segment is directly processed by the machine without welding, which ensures accuracy and flatness. The two small segments are installed as a concave and convex surface inlay combination, and one of the segments is rotated 11.25°-45°, which makes the discharge area more uniform and also makes the continuous strength of the discharge electrode line 203 higher. The entire discharge electrode line 203 is extremely rigid and is made of a solid cylinder 2032, which is easy to transport, more durable, and easy to replace. The length of the electrode line can be adjusted at will according to needs, and the cylinder 2032 can be recycled.

[0054] In this embodiment, the power module 400 for supplying power to the discharge electrode 203 uses a superimposed power supply of a fundamental wave unit 401 superimposed with a narrow pulse unit 402, the fundamental wave unit 401 is used to provide DC high voltage, the narrow pulse unit 402 is used to provide nanosecond pulse high voltage, the discharge frequency ratio of the narrow pulse unit 402 and the fundamental wave unit 401 in the superimposed power supply is: 1:18-24, the electric field strength provided by the narrow pulse unit 402 is greater than 5000V / cm, and the electric field strength provided by the fundamental wave unit 401 is 2000-3800V / cm, so that the discharge electrode 203 has an adsorption effect, because the discharge electrode 203 has an adsorption effect when the fundamental wave unit 401 supplies power, and odorous dust, aerosols, and droplets will be adsorbed to the grounding electrode, solidified and gradually oxidized on the surface of the grounding electrode. Therefore, a spray component 300 is provided on the plasma generating module 200 to regularly spray and remove the adhesion on the surface of the grounding electrode.

[0055] In addition, the distance between the electrodes of narrow gap discharge is very small, the electric field strength is high, and the current density is large. Due to the high electric field strength, the electron energy is correspondingly high.

[0056] For example, the power module 400 may be used as follows: Fig.14 The circuit shown is used to realize the superposition of the fundamental wave unit 401 and the narrow pulse unit 402, and is composed of an AC-DC conversion circuit, a high-voltage DC circuit, and a nanosecond pulse high-voltage circuit. The high-voltage DC circuit outputs DC high voltage, and the nanosecond pulse high-voltage circuit outputs nanosecond pulse high voltage. One end of the high-voltage DC output is grounded, and the other end of the high-voltage DC output is connected to the plasma generation module 200 through a current limiting resistor. One end of the high-voltage pulse output is grounded, and the other end of the high-voltage pulse output is connected to the plasma generation module 200 through a high-voltage coupling capacitor. The two form a DC high voltage superimposed on the nanosecond pulse high voltage on the plasma generation module 200.

[0057] like Fig.14As shown, the AC-DC conversion circuit, the input power supply is three-phase industrial frequency AC power AC1, the A, B, C three-phase industrial frequency AC power is rectified by a three-phase rectifier composed of D1-D6 diodes, and filtered by C1 filter capacitor to convert it into DC power supply DC1. The DC power supply DC1 simultaneously supplies power for the high-voltage DC circuit and the nanosecond pulse high-voltage circuit.

[0058] The high-voltage DC circuit includes a high-frequency H-bridge inverter composed of V11-V14 semiconductor switches, a resonant capacitor C11, a high-frequency step-up transformer TR1, and a high-frequency high-voltage rectifier circuit composed of D11-D14 diodes. The high-voltage DC circuit controls the frequency of the high-frequency H-bridge inverter through two PWM1 and PWM2 drives to control the size of the high-voltage DC circuit. One end of the high-voltage DC1 output is grounded, and the other end of the high-voltage DC1 output is connected to the plasma generation module 200Z1 through the current limiting resistor R11. The circuit equivalent model of the plasma generation module 200Z1 is a capacitor Cz in parallel with a variable resistor Rz in series with a voltage regulator tube Dz.

[0059] The high-voltage DC circuit outputs a continuous DC high voltage on the plasma generating module 200, generates a stable electric field, forms a basic DC corona discharge, and drives the charged particles in the gas to move along the direction of the electric field until they are captured by the dust collecting grounding electrode.

[0060] The nanosecond pulse high voltage circuit is mainly composed of a pulse DC power supply, a pulse generator, a high-voltage pulse energy storage capacitor Cs, a magnetic compression circuit MZ21, and a pulse isolation transformer TR23. The pulse DC power supply includes a high-frequency H-bridge inverter composed of V21-V24 semiconductor switches, a resonant capacitor Cb, a resonant inductor Lb, a high-frequency boost transformer TR21, a high-frequency rectifier circuit composed of D21-D24 diodes, a filter capacitor C22, a current limiting inductor L21, and a diode D21. The pulse generator includes a semiconductor switch V25, an RCD protection circuit composed of D25, R11, and C24, a DC energy storage capacitor Ce, and a pulse boost transformer TR22. The peak voltage of the nanosecond pulse high voltage is adjusted by changing the DC voltage value of the pulse DC power supply by driving and controlling the frequency of the high-frequency H-bridge inverter in the pulse DC power supply through two PWM3 and PWM4. The repetition frequency of the nanosecond pulse high voltage is adjusted by driving and controlling the frequency of the semiconductor switch in the pulse generator through one PWM5. One end of the pulse 2 high voltage pulse output is grounded, and the other end of the pulse 2 high voltage pulse output is connected to the plasma generating module 200Z1 via the high voltage DC blocking capacitor C26. The circuit equivalent model of the plasma generating module 200Z1 is a capacitor Cz in parallel with a variable resistor Rz and a voltage regulator tube Dz in series.

[0061] The nanosecond pulse high voltage circuit outputs nanosecond pulse high voltage at a repetition frequency on the plasma generating module 200. The rising edge of the nanosecond pulse high voltage is less than or equal to 300ns, the pulse width is less than 1us, and the peak voltage can be adjusted. The nanosecond pulse high voltage is superimposed on the DC voltage generated by the high-voltage DC circuit through the high-voltage coupling capacitor. Within 1us, a pulse high-voltage electric field is quickly formed to ionize the gas passing through the plasma generating module 200 with high intensity, forming high-concentration charged ions and free radicals in the gas, which produce electrochemical reactions with odor and odor molecules to eliminate odor and odor in the gas.

[0062] The waveform of DC high voltage superimposed nanosecond pulse power supply is as follows: Fig.15 As shown. The high-voltage DC circuit controls the output of DC1 (i.e., fundamental wave unit 401), and the nanosecond pulse high-voltage circuit controls the output of nanosecond pulse voltage Pulse 2 (i.e., narrow pulse unit 402). After coupling and superposition, a DC plus nanosecond pulse voltage DP1 (i.e., the superposition power supply of fundamental wave unit 401 and narrow pulse unit 402) is output on the load. Fig.15 In the output, the DC voltage DC1 is about 30KV, the output nanosecond pulse voltage Pulse 2 nanosecond pulse peak voltage is about 60kV, and the DC plus nanosecond pulse voltage DP1 peak voltage is about 90KV.

[0063] Nanosecond pulse high voltage circuit waveform diagram, such as Fig.16 As shown. Nanosecond pulse high voltage circuit waveform diagram, PWM5 (its waveform is as follows Fig.16 The driving waveform 5) in the driving control pulse generator is used to drive the semiconductor switch V25, control the working pulse width and frequency of the semiconductor switch V25, the pulse current is the pulse current flowing through the semiconductor switch V25 in the pulse generator, pulse 1 is the microsecond pulse voltage output after being boosted by the pulse boost transformer TR22 in the pulse generator, and pulse 2 is the nanosecond pulse voltage output after being compressed by the magnetic compression circuit MZ21 and isolated by the pulse isolation transformer TR23.

[0064] Comparison between DC high voltage superimposed with nanosecond pulse high voltage and DC high voltage, such as Fig.17As shown. The peak voltage output of 90KV of the plasma generating module 200 connected to the DC high voltage superimposed on the nanosecond pulse high voltage is compared with the plasma generating module 200 connected to the DC high voltage 90KV. When the plasma generating module 200 is connected to the DC high voltage 90KV, it can provide a large average electric field strength and ionize a very high density of electrons and ions, but due to the high average electric field strength, it brings two major problems. The first problem is the insulation problem. The average electric field strength is high, resulting in the plasma generating module 200 After the working gas is passed, the gas is very easy to be broken down and short-circuited, and it cannot operate normally under normal conditions. Reducing the DC voltage operating value voltage to work will cause the density of generated electrons and ions to decrease, affecting the pollution control efficiency of the plasma generating module 200. The second problem is that the operating energy consumption is high, the average electric field strength is high, and the average current is large. The product of the two is power, resulting in a large operating energy consumption. Even if the DC voltage is reduced from 90KV to 50KV, the operating energy consumption is still greater than the DC 30KV plus 60KV nanosecond pulse voltage, and the peak value reaches 90KV output. When the peak voltage output of the DC high voltage superimposed nanosecond pulse high voltage is 90KV, the 90KV nanosecond peak voltage output can instantly generate high-density electrons and ions in the plasma generating module 200. The short output time will not cause the working gas to break down and short-circuit, and the electron and ion density is high, which can greatly improve the efficiency of the pollution control of the plasma generating module 200 and can stably maintain high efficiency at the same time. At the same time, according to the residence time of the polluted gas in the plasma generating module 200, the number of nanosecond peak voltage outputs can be accurately controlled, and the operating energy consumption can be accurately controlled. The DC high voltage superimposed nanosecond pulse high voltage power supply does not need DC high voltage to generate high-density electrons and ions, so the DC high voltage can maintain a very low voltage value. According to the gas flow rate inside the plasma generating module 200, the DC high voltage output is appropriately adjusted to generate a stable electric field, driving the charged particles in the gas to move along the direction of the electric field until the dust collecting grounding electrode is captured, and the DC high voltage operation output P energy consumption is also very low.

[0065] like Fig.18 As shown, under the same working conditions, the two devices A and B use the same discharge electrode wire and the same specifications. Device A uses a single pulse power supply with a pulse field strength of 6800v / cm, and device B uses a superimposed power supply of the fundamental wave unit 401 of this embodiment superimposed with the narrow pulse unit 402. The ratio of the discharge frequency of the narrow pulse unit 402 and the fundamental wave unit 401 is 1:18, the pulse field strength is 6800v / cm, and the fundamental wave field strength is 2200v / cm. Through the experimental data, it can be seen that the deodorization efficiency and dust removal efficiency of device B have been greatly improved, far exceeding the requirements of environmental protection standards.

[0066] In order to realize the automatic operation of the processing equipment and the control of the power module 400, a PLC controller 500 is also included. The power module 400 is electrically connected to the PLC controller 500. The PLC controller 500 is used to control whether the power module 400 supplies power to the discharge electrode line 203, as well as the output power of the pulse power supply and the fundamental wave unit 401.

[0067] In order to detect the quality of the exhaust gas entering the reaction zone, a gas detector 600 for detecting the concentration of pollutants is installed at the air inlet 102. Fig.11 As shown, the gas detector 600 is electrically connected to the PLC controller 500, and the gas detector 600 can detect the concentration of pollutants discharged at the air inlet 102 in real time and transmit the detected information to the PLC controller 500, so that the PLC controller 500 can automatically adjust the output power of the power module 400 in real time according to the concentration of pollutants, as shown in FIG. Fig.12 As shown, when the pollutant concentration is high, by increasing the narrow pulse discharge frequency, the deodorization effect is maximized while ensuring the best efficiency output for each discharge, and at the same time, the fundamental wave discharge is used to achieve the elimination of ozone and the adsorption of dust and droplets, which doubles the efficiency and achieves the purpose of efficient deodorization. When the pollutant concentration is high, the narrow pulse discharge frequency is reduced, and at the same time, the best efficiency discharge is maintained for each discharge to reduce energy consumption, because reducing the narrow pulse discharge intensity will reduce the conversion efficiency. By maintaining the narrow pulse discharge intensity unchanged and reducing the narrow pulse discharge frequency, the efficient discharge of the narrow pulse is ensured while reducing energy consumption, which is suitable for deodorization in an environment with low pollutant concentration. The entire control logic is automatically controlled by the PLC according to the ozone concentration, which can increase energy saving by 20-50%. Of course, in order to detect the effect of pollutant treatment, a gas detector 600 can also be installed at the outlet 103.

[0068] In this embodiment, if Figure 5 As shown, the discharge plate 2033 has a guiding function. When the gas enters the reaction zone, it hits the discharge plate 2033, and the gas rotates, so that the gas spirals through the reaction zone, and at the same time, it can throw the droplets and dust in the gas onto the cylinder wall, and finally solidify on the cylinder wall through the discharge adsorption reaction. The continuous rotation of the gas increases the path and reaction time in the reaction zone, which is beneficial to increase the waste gas treatment efficiency and reaction intensity. Figure 8 It can be seen that the range of the discharge reaction area of ​​the single-piece discharge plate 2033 is equivalent to the discharge reaction area formed by rotating the conventional double-piece discharge plate 2033 by 22.5°.

[0069] like Figure 4As shown, it is a spray assembly 300, and the spray assembly 300 is used to remove attachments on the plasma generating module 200. Exemplarily, the spray assembly 300 includes a water supply pipe 301, and the water supply pipe 301 is equipped with a plurality of nozzles 302, spraying toward the plasma generating module 200, and the water supply pipe 301 is connected to a high-pressure water source and is equipped with a third valve 309 for controlling the high-pressure water source, wherein the third valve 309 is a solenoid valve, which is electrically connected to the PLC controller 500, as shown in FIG. Fig.13 As shown, the PLC controller 500 can control the solenoid valve to open the spray assembly 300 at a fixed time, and close the narrow pulse discharge during the spraying process to avoid discharge flashover. The fundamental wave unit 401 normally supplies power to the discharge electrode line, and the fundamental wave discharge acts as an electric demister, which can play an electric demister role and ensure that the spray droplets are electrically adsorbed on the barrel wall to achieve the purpose of efficient cleaning, thereby removing the attachments on the barrel wall by spraying water within a specified time period.

[0070] In order to collect waste water generated when the spray assembly 300 removes the attachments on the plasma generating module 200, a water receiving tray 303 is arranged below the plasma generating module 200. The water receiving tray 303 is connected to a water tank 305 via a water inlet pipe 304. The water inlet pipe 304 is equipped with a first valve 306. The water tank 305 is connected to a drain pipe 307. The drain pipe 307 is equipped with a second valve 308. The first valve 306 is also a solenoid valve. The first valve 306 is electrically connected to the PLC controller 500. Fig.11 As shown, the first valve 306 is controlled by the PLC controller 500. In this way, when the spray assembly 300 sprays water, the PLC controller 500 can open the first valve 306 and turn off the power supply of the narrow pulse unit 402. Only the fundamental wave unit 401 supplies power to the discharge electrode line of the plasma generating module 200, so that the waste water collected by the water receiving tray 303 enters the water tank 305 along the water inlet pipe 304. When the spray assembly 300 is not working, the PLC controller 500 can close the first valve 306 to prevent the waste gas in the reaction zone from entering the water tank 305. When the waste water in the water tank 305 accumulates to a certain amount, the waste water in the water tank 305 can be discharged by opening the second valve 308.

[0071] In this embodiment, the treatment of waste gas is divided into two stages. The first stage is dominated by a pulse power supply. Under high electric field strength (greater than 5000V / cm), discharge generates free electrons. Under the action of the electric field force, the electrons accelerate and gain energy. The energy range is between 0 and 20eV, and the maximum energy distribution probability is approximately between 2 and 12eV. The bond energy of the main chemical bonds in organic molecules is within the maximum energy distribution range. Therefore, when free electrons collide elastically or inelastically with organic molecules, when the energy of the free electrons is the same or similar to the chemical bond energy of the organic molecules, the free electrons transfer most of their energy to the organic molecules they collide with, breaking these bonds and thus destroying the molecular structure of the organic matter. At the same time, substances with strong oxidizing ability, represented by ozone, will be produced during the discharge process. After the free electrons destroy the molecular structure of organic matter, substances such as ozone can easily react with these organic matter or directly oxidize them, ultimately promoting the development of organic matter towards the generation of CO2 and H2O (Note: when the electron energy is between 2-6.1eV, only ozone will be decomposed; when the electron energy reaches 12.5eV, only ozone will be produced; when the electron energy is between 6.1-12.5eV, ozone will both be produced and decomposed).

[0072] The second stage is dominated by the fundamental wave unit 401. Under low electric field strength (2000-3800V / cm), it continues to discharge to generate free electrons. Its energy field is relatively low, but it still meets the electron energy required for the decomposition of ozone and some organic matter. It can decompose the ozone and remaining organic matter generated under high electric field strength, achieve effective attenuation, and thus avoid secondary pollution. Ozone is decomposed into more active oxygen free radicals, which continue to react with the remaining organic matter, improving the reaction efficiency of this stage. Under this electric field, there is also an electrosorption effect, and aerosols, droplets and other substances can be removed without additional energy input. In addition, since the single discharge time of the pulse power supply is extremely short and the instantaneous power reaches the megawatt level, maintaining a low electric field strength can reduce the energy consumption required by the pulse power supply to generate a high electric field strength, improve energy conversion efficiency, and save electricity.

[0073] For example: In working conditions such as pumping stations where odor fluctuates greatly, it is difficult for traditional plasma equipment to make real-time adjustments. This causes odor to overflow. The waste gas treatment equipment of the present application can perform stepless regulation of the equipment through a PLC controller 500 according to the concentration of pollutants (the concentration of pollutants is obtained by the gas detector 600 at the air inlet 102). A gas detector 600 is installed at the air inlet 102 of the equipment, which can detect the concentration of pollutants in real time and feed it back to the PLC control system. When the concentration of pollutants increases, by increasing the number of narrow pulse discharges per unit time, that is, the discharge frequency, more organic matter, inorganic matter and odor are removed while ensuring the optimal efficiency output of each discharge. At the same time, the power of the fundamental unit 401 also increases, further reacting the remaining products and ozone of the previous reaction (that is, the narrow pulse discharge stage), increasing the oxidizing environment, and preventing ozone from escaping. The air outlet 103 is provided with an ozone detector 700. When the ozone concentration is detected to exceed the setting, the power of the fundamental wave unit 401 is also raised or the narrow pulse discharge frequency is increased. Otherwise, the power of the fundamental wave unit 401 is reduced or the narrow pulse discharge frequency is reduced. When the pollutant concentration is low, it does not require so much energy to remove the pollutants, so the narrow pulse discharge frequency is appropriately reduced, and the power of the fundamental wave unit 401 is also reduced accordingly.

[0074] The multi-modal high-voltage electric field coupling superposition technology of this embodiment increases the concentration of treatable pollutants compared to a simple pulse power supply during the pollutant treatment process, while reducing the energy consumption of the equipment, improving the equipment's treatment efficiency, solving the problem of ozone overflow, and effectively removing dust and droplets in the gas. Droplets in the gas often carry a strong odor, and certain substances in the exhaust gas may undergo chemical reactions in the droplets under certain conditions to generate more malodorous substances. Or the pollutants in the droplets may be enriched on the surface of the droplets by physical adsorption. When the droplets evaporate or break, these malodorous substances are released, resulting in an increase in odor concentration. Adsorbing and solidifying the droplets in the equipment can greatly reduce odor escape.

[0075] The above are only preferred specific implementations of the present application; however, the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical solution and its improved ideas of the present application within the technical scope disclosed in the present application, which should be included in the protection scope of the present application.

Claims

1. An exhaust gas treatment device with a fundamental wave and narrow pulse superposition power supply, characterized in that: include: A housing, wherein the housing has a channel, one end of the channel is provided with an air inlet, and the other end of the channel is provided with an air outlet; A plasma generating module, the plasma generating module comprising an upper bracket, a lower bracket and a discharge electrode wire, the upper bracket and the lower bracket are installed in the channel at a distance, and a plurality of discharge electrode wires are installed between the upper bracket and the lower bracket; A spray assembly, wherein the spray assembly is used to remove attachments on the plasma generating module; A power supply module is used to provide superimposed power of a fundamental wave unit and a narrow pulse unit to the discharge electrode line.

2. The exhaust gas treatment device with a fundamental wave and narrow pulse superposition power supply according to claim 1, characterized in that: The discharge electrode includes a connecting rod, and a plurality of columns are sleeved on the outer wall of the connecting rod. A plurality of discharge plates are integrally formed at one end of the column, and the discharge plates are arranged to be a polygonal structure. A specified angle is reserved between the discharge plates and the end face of the column, and the specified angle is 68°-85°. A plurality of limiting grooves are reserved at one end of the column, and a limiting protrusion adapted to the limiting groove is reserved at the other end of the column. The length of the column is 35mm-40mm, and the rotation angle between adjacent columns is 11.25°-45°.

3. The exhaust gas treatment device with a fundamental wave and narrow pulse superposition power supply according to claim 1, characterized in that: The ratio of the discharge frequency of the narrow pulse unit and the fundamental wave unit in the superimposed power supply is 1:18-24.

4. The exhaust gas treatment device with a fundamental wave and narrow pulse superposition power supply according to claim 1, characterized in that: The electric field strength provided by the narrow pulse unit is greater than 5000V / cm, and the electric field strength provided by the fundamental wave unit is 2000-3800V / cm.

5. The exhaust gas treatment device with a fundamental wave and narrow pulse superposition power supply according to claim 1, characterized in that: A water receiving tray is arranged below the plasma generating module. The water receiving tray is connected to a water tank via a water inlet pipe. The water inlet pipe is provided with a first valve.

6. The exhaust gas treatment device with a fundamental wave and narrow pulse superposition power supply according to claim 1, characterized in that: It also includes a PLC controller, and the power module is electrically connected to the PLC controller.

7. The exhaust gas treatment device with a fundamental wave and narrow pulse superposition power supply according to claim 6, characterized in that: The water supply pipe of the spray assembly is installed with a third valve, the first valve and the third valve are both solenoid valves, and the control ends of the first valve and the third valve are both electrically connected to the PLC controller.

8. The exhaust gas treatment device with a fundamental wave and narrow pulse superposition power supply according to claim 6, characterized in that: The air inlet is equipped with a gas detector for detecting the concentration of pollutants, and the air outlet is equipped with an ozone detector. Both the gas detector and the ozone detector are electrically connected to the PLC controller.

9. The exhaust gas treatment device with a fundamental wave and narrow pulse superposition power supply according to claim 1, characterized in that: A buffer material for slowing down the flow rate of gas is filled in the area between the gas outlet and the plasma generating module in the channel.

10. The exhaust gas treatment equipment with a fundamental wave and narrow pulse superposition power supply according to claim 1, characterized in that: The air inlet is provided with a filter assembly.

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