TWI392521B - Plasma torch air purifier - Google Patents

Description

Plasma torch air purifier

The present invention is directed to the design of an air purifier that uses a plasma torch to complete sterilization. The invention includes a new magnetized torch module, a control air valve design, and assembly into an air purifier. The magnetized torch module increases airflow and maintains stable arcing. Use two torches alternately to eliminate the need for cooling. The control air valve directs air flowing out of the power-off torch module laterally through the torch of the discharged torch module. The torch's plasma fluid carries a large amount of active oxygen atoms that kill all types of microorganisms. Therefore, although only one torch is in operation, the air flowing through the two torch modules is processed. The application of the device is the purification and disinfection of air.

A general air purifier uses a filter to remove dust and/or microorganisms from the air. Filters do not kill microorganisms, so care must be taken to clean or replace the filter.

SPKuo et al. invented a torch module; the description of the torch module is published in IEEE Trans. Plasma Sci. Vol. 27, No. 3, pp. 752-758, 1999, entitled "Design and Electrical Characteristics of a Module Torch"; And is described in U.S. Patent No. 6,329,628, entitled "Method and Apparatus for Producing a Plasma Torch". The torch module applies an external air flow to stabilize the discharge, and forms a plasma blow-out module formed by the discharge into a plasma torch. The torch module can operate in a low frequency (60 Hz) periodic discharge mode to produce a low temperature unbalanced air plasma in which the kinetic energy of the electrons is not fully heated. In an unbalanced plasma torch, the kinetic energy of the electrons is not completely heated, so there is a sufficient amount of kinetic energy to decompose the oxygen molecules into reactive oxygen species (ROS) rather than heating the flare gas stream. Reactive oxygen species (especially active oxygen atoms (RAO) can effectively kill microorganisms including the most stubborn pathogens, bacterial spores such as Anthrax (see Phys. Plasma, Vol. 6, pp. 2284-2289, 1999, HW Herrmann et al., "Using Atmospheric Pressure" Plasma Jet (APPJ) to remove chemical and biological warfare agents (CBW) pollution (hereafter Herrmann article), and Phys. Plasma, Vol. 12, 023501 (1-6), 02/2005, Wilson Lai et al. "Using microwave plasma to remove the contamination of biological warfare agents" (hereafter referred to as Lai article)).

The discharge voltage required for air discharge is proportional to the gap between the two (concentric) electrodes. Therefore, the gap is generally small, limiting the air flow. The application of air purification requires a large flow rate; however, the flow rate of the airflow through the gap is proportional to the cross-sectional area of the annular gap, which is the product of the gap width and the circumference of the annular gap. The circumference of the ring gap can be increased by increasing the radial dimension of the flare module. Operating multiple torch assemblies simultaneously can also increase flow.

The newly designed air purifier kills microorganisms in a clear manner, so the filters used to collect dust and die microorganisms are not contaminated.

For the design of the torch module, the outer diameter of the external electrode can be increased to 20 mm. The center electrode is a plug-in copper disc with a diameter of 18 mm, that is, the side of the disc has a groove. The slatted sheet structure enhances discharge performance and increases gas flow at the same gap width. Figure 1 is a schematic view of the torch module (a), wherein the photo shown is: module holder (b), center electrode (c), module side view (d), And the schematic view (e) of the module. The air purifier is designed to produce a plasma torch that treats air by alternately operating two torch modules. The device is designed with synchronous control air valve so that the airflow passing through the two torch modules can be processed by the torch; that is, the airflow generating the torch is automatically processed by the torch; the air flowing out of the power-off torch module is laterally through a duct The ground flows through the torch and is processed.

The advantages of using two torches and alternate operations are: 1) eliminating the need for cooling of the flare module, and 2) doubling the airflow and air handling speed.

Figure 2 is a system diagram. As shown, the device has four layers; from the bottom, the first layer contains a pair of torch modules and power supplies. This layer has an air inlet located next to the power supply that allows the air to cool the power supply before it flows to the flare module. Figure 3 is a detailed schematic of the torch module pair. As shown, the torch module is covered by a duct located on the upper layer of the control air valve. The control air valve has a duct and two valve guides at both ends that control the flow direction of the airflow exiting the flare module in the duct. Figure 4a shows the control air valve. The air duct has an electrical ground; the two valves connected to the two module grounding wires are electrically insulated from the air duct when in the open position, but are connected to the air duct when the valve is in the closed position. As shown in Figures 4a and 4b, the two valves are connected by a pull-type linear solenoid valve fixed to the side wall of the duct, and are alternately closed and opened to be connected and disconnected from the grounding line of the circuit for controlling the opening and closing of the two torches. . For example, as shown in Figure 3, when the left (LHS) valve is closed, the right valve is open; therefore, the ground wire of the right (RHS) torch module is in electrical contact with the air duct to energize the torch module. Therefore, the airflow flowing out through the left closing module is forced to the right and is processed by the plasma torch generated by the right torch module. The electric switch of the solenoid valve is fixed on the upper side of the air duct. As shown in Figures 4b and 4c, this A "push-release electric switch" uses a synchronous AC gear motor fixed to the other side of the duct to form a timer that mechanically switches for a set period of time (determined by the rotational speed of the motor (RPM)). The third layer is equipped with a centrifugal fan that draws the processing air of the second layer of ducts to the upper air filter. The treated air passes through the filter and exits the air purifier.

The power supply used in the present invention has a simple circuit as shown in FIG. Use a normal AC power source, such as a 60 Hz (or 50 Hz) household outlet. The transformer's revolution ratio is 1:17 based on the 120V input voltage. If the input voltage is 220V, it is reduced to 1:9.

The present invention focuses on an innovative design of an air purifier equipped with a plasma torch; the plasma fluid using the discharge and plasma torch purifies the contamination of microorganisms and chemicals in the air. Arc discharge directly kills microorganisms, while reactive oxygen atoms (RAO) produced by plasma fluids are used to kill microorganisms and neutralize chemicals via oxidation. The following description is not only to enable the person skilled in the art to make and use the invention, but also to the particular application of the invention and its application. Data modifications relating to specific embodiments are contemplated by those skilled in the art, and the general principles described below are also applicable to other specific embodiments and applications. Therefore, the scope of the invention is not limited to the specific embodiments shown in the specification.

In the following, Section 6.1 describes the functions that can be carried out by the present invention. Section 6.2 illustrates the construction of a device made in accordance with the present invention. Section 6.3 describes the application of the invention. Section 6.4 describes the operation of the unit. Finally, Section 6.5 presents the conclusions of the present invention.

6.1 function

The invention is used to purify air to achieve safe and high quality breathing air; the device's plasma torch produces a large amount of reactive oxygen atoms in its plasma fluid. Active oxygen atoms are effective in killing all types of microorganisms and neutralizing chemicals. In addition, microorganisms in the gas stream of the discharged torch module are directly killed by arc discharge and heat. Dust and chemicals in the air are eliminated by combustion, neutralization, and final filtration. The torch also produces healthy gases such as nitrogen oxides (NO) (see Kuo et al., published in IEEE Trans. Plasma Sci., vol. 32, pp. 262-268, 2004, entitled "The Plasma Torch Generated by the Periodical Discharge of Torch Modules" Description of the characteristics" (hereinafter referred to as Kuo's article)). Nitric oxide protects the heart, stimulates the brain, kills bacteria, etc.; the above functions are stated in the news of the Nobel Conference of the Karolinska Institute in October 12, 1998.

6.2 structure

The following is an air purifier designed according to the system configuration instructions of Figure 2.

As shown in Fig. 1, the magnetized torch module (101) used in the device uses a ring-shaped permanent magnet (102); the module has two main components: a cylindrical seat (111) as a module of a gas static pressure box (112), an external electrode (113), and a holder of the annular permanent magnet; and a spline circular disk type center electrode (121); the disk is passed through a ceramic tube (123) The conductive rod (122) is supported. As shown in Figures 1(a) and (d), the ceramic tube (123) keeps the conductive rod (122) insulated from the cylindrical seat (111) and is fixed to the cylindrical seat (111) by a fixing screw (103). Center axis position. Figure 1 (e) is a top plan view of a torch module without a magnet.

The apparatus shown in Fig. 2 is composed of four parts stacked in four layers ((201), (202), (203), and (204)). The lowermost layer (201) places the torch module (101) and the power supply unit (221). As shown, this layer has There is an air inlet located next to the power supply. The air thus flowing can be cooled (221) before flowing into the flare module (101). The two torch modules operate alternately; however, air continuously flows through the two modules, and the airflow cools the torch module during a power outage. Therefore, the second layer (202) is provided with a control air valve (212) for directing the untreated airflow from the power-off torch module and flowing laterally through the plasma torch generated by the discharged torch module (Fig. 3 (320)). The control air valve (212) is composed of an electrically grounded metal pipe ((311) in Fig. 3) and two air valves ((312) and (316) in Fig. 3) at both ends. The two air valves are controlled by a pull type linear solenoid valve (222) for alternate switching. The solenoid valve timer (pressure-release electric switch and synchronous AC gear motor) is not shown. This control air valve also represents the electrical switch (513) of Figure 5. As shown in Figure 3, the ground wire (313) of each torch module is connected to a conductive strip (317) on the other end air valve (312) or (316). For example, when the air valve (312) is in the open position, it is electrically insulated from the conduit (311), causing the torch module (314) at the other end to be powered down. At the same time, the other air valve (316) is closed, and the conductive strip (317) is electrically connected to the contact piece (318) at the upper end of the outlet of the pipe (311); the torch module (315) at the other end is In the discharge condition. Therefore, the electrical switch of the torch module is synchronized with the closing of the air valves ((312) and (316)).

The fan (213) is located on the third layer (203). The fan twitches the airflow. Air is drawn in from the underlying air inlet and then pumped through the air filter (214) of the uppermost layer (204) and discharged.

Figure 3 is a detailed schematic view of a pair of flare modules ((314) and (315)) and their control air valves (212). As shown in FIG. 3, the metal conduit (311) of the control air valve (212) covers the airflow outlet of the flare module and serves as a treatment zone for controlling the flow direction of the airflow and the airflow. The conductive rods (122) of the center electrode of the two torch modules are connected to a common power supply high voltage through wires (321) end.

4 is a schematic illustration of a control air valve (212). Figure 4a shows the main body consisting of an electrically grounded metal pipe (311) and two non-conducting air valves ((312) and (316)); mounted on the top of the flare module to control the flow of the torch module exhaust airflow . A conductive strip (317) is mounted on the valve plate to electrically contact the metal conduit (311) in the closed position. The conductive strip (317) is connected to the ground wire (313) of the torch module at the other end. Figure 4b shows a complete combination of control air valves (212). The switching action of the air valves ((312) and (316)) is controlled by the pull-type solenoid valve (222) shown in Figure 4b, alternately opening and closing according to a set period of time (e.g., 10 s). The closing timer of the solenoid valve (222) is composed of a pressure-release electric switch (422) and a synchronous AC gear motor (412).

The power supply (500) used in the present invention has a simple circuit as shown in Fig. 5; a conventional AC power source such as a 60 Hz (or 50 Hz) household wall socket is used. This power supply uses a single power transformer (511) with a conversion ratio of 1:17 to boost the outlet's output voltage from 120V to 2 kV (rms), which is the highest voltage of 2.83 kV (this transformer may be available with an inverter (inverter) ))). The output of the transformer is connected to a 1μF capacitor (512) and then connected to the center electrode of the two torch modules ((314) and (315)). The electric switch (513) connects the grounding wires of the two torch modules, and the two torch modules are alternately discharged and power-off, and synchronized with the closing and opening of the air valve. As shown in Figure 2, the power supply (221) on the right side of the bottom layer (201) is placed close to the air inlet so that the inflowing air can effectively cool the power supply.

6.3 Application of the invention 6.3.1 Air purification and disinfection

The inventive device manufactured according to the description in Section 6.2 can be used to purify the surrounding air and let the call Safe and healthy. Removal of dust powder through combustion and filtration; killing of disease-causing microorganisms via discharge, flare heating, and oxidation (using active oxygen atoms); neutralization of chemicals via oxidation; and generation of healthy gases that help to breathe such as nitrogen oxides (NO) .

6.3.2 Application

Application of the inventive device manufactured according to the instructions in Section 6.2, including 1) home air sterilizer/purifier, 2) combined with the building central air conditioning system to purify the air, and 3) hospital use to enhance the sterility and maintenance of the sterile room The air quality of the sterile room.

6.4 Operation of the specific embodiment

According to the air purifier described in Section 6.2, the power cord can be plugged into a standard household 120V wall socket. The voltage (601), current (602), and power (603) for operating the torch discharge function are shown in FIG. The arc has a starting voltage of about 3 kV and a maximum arc current of less than 5A. The maximum power is less than 2 kW; the average power is about 400W lower than the rated 1.8 kW of the household 15 A circuit breaker. The two torches can be switched on and off alternately, for example, 10 seconds (using a 3 RPM synchronous AC gear motor as a timer).

Based on existing fans and speeds, the unit can purify air at a rate of 300 to 600 liters per minute.

6.5 Conclusion

The present invention contemplates a magnetized torch module that is capable of circulating a large amount of gas stream and producing a plasma fluid that carries a plurality of active oxygen atoms. The invention of the plasma torch air purifier operates two of the torch modules simultaneously applying heat treatment and non-heat treatment (using active oxygen atoms) to purify and disinfect the surrounding air. Since the filter of the device is not contaminated, the filter can be safely replaced. Device completion Can test. The results demonstrate that the device can handle ambient air at a rate of 300 to 600 liters per minute. Only moderate power is consumed.

The manufacture of such an air purifier can use existing components of the market, such as fans, filters, pull-line solenoid valves, synchronous AC gear motors, and circuit components of the power supply; and the design components detailed in Section 6.2, Includes torch module and control air valve.

Figure 1 includes (a) schematic diagram of the magnetized torch module, (b) schematic diagram of the module holder, (c) schematic diagram of the center electrode, (d) schematic view of the module (without magnet), and (e) top view of the module Schematic (no magnet).

Fig. 2 is a configuration diagram of the present invention.

Figure 3 is a detailed configuration diagram of a pair of flare modules covered by a controlled air valve.

Figure 4 is a schematic view of the control air valve; showing (a) a duct and two air valves, and (b) a complete combination comprising a pull-line solenoid valve (222), a synchronous AC gear motor (412) , a pressure-release electrical switch (422), and electrical connections.

Figure 5 is a circuit diagram of the power supply.

Figure 6 shows the time function of the voltage (601), current (602), and power (603) of the discharge.

Claims (4)

An air purifying device for purifying and disinfecting ambient air to provide safe and healthy breathing; the device comprising: a pair of magnetized torch modules for generating a plasma torch by using a high voltage discharge; and a pair of control air valves, the pair of gases The valve is located at both ends of a pipeline treatment zone, and alternately turns off and on to guide the flow of the airflow in the pipeline, and alternately converts the torch module to discharge and power down; a high voltage power supply, the power supply starts the torch module; A fan that draws air into the device to cool the power supply, supply air to the torch module, and pump the treated air through a filter back to the atmosphere. The device of claim 1, wherein the magnetized torch module comprises: a cylindrical seat, a center electrode, an insulating porcelain tube, and an annular permanent magnet; the cylindrical seat serves as an external electrode and a gas static pressure box, And as a frame of the annular permanent magnet; the center electrode is a plug-type copper disk, the copper disk is supported by a conductive rod; the conductive rod is inserted into the ceramic tube along the central axis of the cylindrical seat to fix the center position of the copper disk, And connect the wire to the high voltage power supply. For example, in the device of claim 1, wherein the two torch modules share a single high-voltage power supply, and the discharge-power-off operation alternates; the power-off-discharge of any of the torch modules and the closing and opening of the air valve near one end of the torch module Synchronization; therefore, the untreated airflow from the power-off torch module must also flow through the plasma torch generated by the torch module being fired, using the active oxygen atoms carried by the plasma torch to obtain non-heat treatment. For example, in the device of claim 1, wherein the input power of the high voltage power supply adopts a 60 Hz/120 V (rms) AC power supply, and the time average power consumption is 600 W.