The present invention relates to an apparatus and method for manufacturing particles, and more particularly, to an apparatus and method for manufacturing particles using corona discharge.
Generally, particles are manufactured by a method of collecting them through a filter or sticking them to a collecting plate after they have been formed by using flames or a furnace. According to this method, metal oxide such as SiO2 or Fe2O3 having ultrahigh purity are obtained.
However, in conventional methods for manufacturing the particles, there are some disadvantages in that their collecting efficiency is very low, and in that sizes of the collected the particles cannot be controlled. In addition, there are problems in that most of the particles that are not collected cannot be recovered, and in that since the particles that have been recovered are mainly metal oxide, they may contaminate the environment. Especially, in the conventional method for manufacturing the particles by using the filter, there is a trouble in that the filter should be frequently replaced due to serious contamination of the filter.
An object of the present invention is to provide an apparatus and method for manufacturing particles using corona discharge, in which very high collecting efficiency can be obtained.
Another object of the present invention is to provide an apparatus and method for manufacturing particles using corona discharge, in which sizes of the particles can be controlled.
In order to achieve the above objects, according to an aspect of the present invention, there is provided an apparatus for manufacturing particles using corona discharge comprising a guide duct; a discharging device of which a discharge electrode is positioned within the guide duct, and which generate ions through electric discharge; a reaction gas supplying device for supplying reaction gases into the guide duct; a voltage applying device connected to the discharging device and the guide duct so as to generate voltage difference therebetween; a heating device which is disposed on an outer surface of the guide duct for applying energy to the reaction gases so as to generate particles which are adhered to the ions generated by the discharging device; a collecting device disposed to be spaced apart from outlet of the guide duct by a predetermined distance for collecting the particles.
According to another aspect of the present invention, there is also provided an apparatus for manufacturing particles using corona discharge, comprising a first guide duct; a second guide duct positioned at an outer side of the first guide duct and having an axis coaxial with the first guide duct; a fourth guide duct positioned at an outer side of said second guide duct and having an axis coaxial with the said second guide duct; a discharging device of which discharge electrode is positioned within the first guide duct, and which generate ions through electric discharge; a reaction control gas supplying device which supplies reaction control gases into the first guide duct so as to generate a lot of ions from the discharging device and to prevent chemical reaction from occurring around the discharge electrode; a reaction gas supplying device for supplying reacting gases into the second guide duct; a fuel gas supplying device for supplying fuel gases into the fourth guide duct; a voltage applying device connected to the discharging device and the first guide duct so as to generate voltage difference therebetween; a collecting device disposed to be spaced apart from outlet of the guide ducts by predetermined distance for collecting the particles of reaction gases adhered to the ions.
According to a further aspect of the present invention, there is provided a method for manufacturing particles using corona discharge, comprising the steps of preparing an apparatus for manufacturing particles using corona discharge comprising a guide duct with a discharge electrode positioned therein, a voltage applying device connected to the discharge electrode and to the guide duct, and a collecting device for collecting the particles; applying high voltage to the discharge electrode and applying low voltage to the guide duct, while generating ions through the discharge electrode and guiding the generated ions along the guide duct; supplying reaction gases into the guide duct; applying energy to the reaction gases to generate particles which are adhered to the ions; collecting the particles adhered to the ions by the collecting device positioned in front of the guide duct.
a is a sectional view showing a third embodiment of an apparatus for manufacturing particles according to the present invention,
b is a perspective view of the guide duct shown in
Hereinafter, embodiments of an apparatus and method for manufacturing particles using corona discharge according to the present invention will be explained in detail with reference to the accompanying drawings.
First, the constitution of a first embodiment of an apparatus for manufacturing particles according to the present invention will be explained with reference to
Thus, a high voltage is applied to the discharge electrode 10 from a power supply 40, while a low voltage having the same polarity as the voltage applied to the discharge electrode 10 is applied to the guide duct 20. In order to generate a voltage difference between the discharge electrode 10 and the guide duct 20, a first variable resistor 42 drops a high voltage form the power supply 40. In addition, a second variable resistor 44 is connected to the first variable resistor 42 so as to further drop the voltage dropped by the first variable resistor 42, and is connected to ground. If the first and second variable resistors 42, 44 have the equal voltage level, a voltage applied between the discharge electrode 10 and the guide duct 20 becomes the same as a voltage applied between the guide duct 20 and the ground. In the present embodiment, although the variable resistors 42, 44 are used for generating the voltage difference between the discharge electrode 10 and the guide duct 20, they may replaced with fixed resistors. In addition, instead of the single power supply 40 and two variable resistors 42, 44, two power supplies may be used so that a high voltage can be applied to the discharge electrode and a low voltage can be applied to the guide duct 20.
A supporting member 30 is fitted into the guide duct 20. The discharge electrode 10 is installed to pass through the supporting member 30, and the supporting member 30 has throughholes 32, 34, 36 adapted to communicate with the interior of the guide duct 20. In order to assist in generating a lot of ions and prevent chemical reaction from occurring by strong energy around the region where the corona is generated, reaction control gases such as CO2 or N2 are supplied by a reaction control gas supplying means 50 through the central throughhole 32. Oxidation gases capable of generating chemical reaction such as O2 or H2 are supplied by an oxidation gas supplying device 52 through the throughhole 34. Reaction gases such as SiCl2 or GeCl4 which move with carrier gases such as N2 or Ar are supplied by reaction gas supply device 54 through the throughhole 36. In the present embodiment, although the oxidation gases and the reaction gases are supplied through the the throughholes 34, 36, respectively, the oxidation gases and the reaction gases are mixed and supplied through the one throughhole. Since well-known devices are adaptable to the reaction control gas supplying device 50, the oxidation gas supplying device 52 and reaction gas supplying device, detailed descriptions related thereto will be omitted herein.
A heater 60 for heating the guide duct 20 and applying energy to the reaction gas which can generate particles is installed around an outer surface of the guide duct 20. A conventional heat generator using resistance wires is used as the heater 60, and a device capable of applying the energy to the guide duct 20, such as an infrared lamp or an ultraviolet lamp, may be used.
A collecting plate 70 is disposed to be spaced apart from the guide duct 20 by a predetermined distance in front of the outlet of the guide duct 20. The collecting plate 70 is electrically grounded, and a cooler 80 for cooling the collecting plate 70 is connected to the collecting plate 70 so as to increase its collecting efficiency. The cooling of the collecting plate 70 is carried out by the conventional cooler 80 capable of injecting cold substances into the collecting plate 70 or maintaining the collecting plate 70 at a low temperature.
Next, the constitution of a second embodiment of an apparatus for manufacturing particles according to the present invention will be explained. The second embodiment uses flames instead of the heating means 60 of the first embodiment. Referring to
Meanwhile, a second guide duct 23 having an axis coaxial with that of the first guide duct 21 is disposed at outer side of the first guide duct 21, a third guide duct 25 having an axis coaxial with that of the second guide duct 23 is disposed at outer of the second guide duct 23, and a fourth guide duct 27 is disposed at outer of the third guide duct 25. A supporting member 30 is fitted into the first, second, third and fourth guide ducts 21, 23, 25, 27, and the discharge electrode 10 is installed to pass through the supporting member 30. In the supporting member 30, a first throughhole 31, a second throughhole 33, a third throughhole 35 and a fourth throughhole 37 are formed to communicate with the first guide duct 21, the second guide duct 23, the third guide duct 25 and the fourth guide duct 27, respectively.
Through the first throughhole 31, similarly to the first embodiment, a chemical reaction control gas supplying device 54 supplies chemical reaction control gases so as to assist in generating a lot of ions from the discharge electrode 10 and to prevent chemical reaction from occurring by the strong energy around the discharge electrode. Through the second throughhole 33, a reaction gas supplying device 54 supplies reaction gases such as SiCl4 or GeCl4. Through the third throughhole 35, a sheath gas supplying device supplies sheath gases and through the fourth throughhole 37, fuel gas supplying device 58 supplies fuel gases. The sheath gases prevent heat of flames from being transferred to the first guide duct 21 when the flames occur at the end of the fourth guide duct 27 by means of ignition of the supplied fuel gases. At the same time, the sheath gases prevent the reaction gases discharged from the interior of the second guide duct 23 from chemically reacting at the end of the second guide duct 23.
Next, the constitution of a third embodiment of an apparatus for manufacturing particles according to the present invention will be explained. Referring to
Next, the constitution of a fourth embodiment of an apparatus for manufacturing particles according to the present invention will be explained. Referring to the
Now, a method for manufacturing particles using corona discharge according to the present invention will be explained with reference to
First, the apparatus for manufacturing particles using corona discharge comprising the guide duct 20;21 wherein the discharge electrode 10 is positioned, the power supply 40 which is applied to the discharge electrode 10 and the guide duct 20;21 and the variable resistors 42, 44 which are connected to the guide duct 20;21 as the voltage applying device, and the collecting plate 70 for collecting the particles are prepared (S10). After preparing the apparatus for manufacturing particles having the mentioned elements, the different voltages are applied to the discharge electrode 10 and the guide duct 20 or the first guide duct 21, respectively (S20). Then, since a high voltage is applied to the discharge electrode 10 by means of the power supply 40 having high voltage level and a low voltage is applied to the guide duct 20 or the first guide duct 21, a lot of ions are generated from the discharge electrode 10 by means of the corona discharge as an electric discharge. Meanwhile, according to configuration of the first embodiment, the reaction gases are supplied to the interior of the guide duct 20 (S30). The generated ions move to the down stream of the guide duct 20 along the flow of the reaction gases supplied through the throughholes 32, 34, 36. At this time, since the voltage having the same polarity as that of the voltage applied to the discharge electrode 10 is applied to the guide duct 20, the ions generated from the discharge electrode 10 are not attached to the guide duct 20.
According to the configuration of the first embodiment, since the guide duct 20 is heated by the heater 60, the interior of the guide duct 20 goes into a high temperature state. Accordingly, the reacting gases reach a high temperature region and react chemically at the high temperature region (S40). As these chemical reactions occur, metallic or non-metallic particles are formed. By using ions distributed around the particles as nuclei, new particles P are formed. Therefore, these particles thus formed are naturally charged and quickly discharged to the outside of the guide duct 20 by the electric field gradient existing in the interior of the guide duct 20 and their flow steam. At this time, since these particles have the same polarity, the particles do not adhere to each other.
Next, since the collecting plate 70 is positioned in front of the outlet of the guide duct 20, the metallic or non-metallic particles formed through the chemical reactions at the high temperature region of the guide duct 20 as described above move to the outside of the guide duct 20 and continuously adhere to the collecting plate 70 (S50). At this time, since the particles have the same polarity, the particles do not adhere to each other, but adhere to the collecting plate 70. In addition, since the collecting plate 70 is cooled by the cooler 80, the particles efficiently adhere to the collecting plate 70. As described above, the particles discharged from the guide duct 20 very efficiently adhere to the colleting plate 70 through two physical phenomena, i.e., electric field and thermophoresis.
According to the constitution of the second embodiment, in order to assist in generating a lot of ions from the discharge electrode 10 and to prevent chemical reaction from occurring by the strong energy around the discharge electrode 10, the chemical reaction control gases such as CO2 or N2 are supplied to the interior of the first guide duct 21. The reaction gases such as SiCl4 or GeCl4 are supplied between the first guide duct 21 and the second guide duct 23 (S30), and the sheath gases are supplied between the second guide duct 23 and the third guide duct 25. The fuel gases are supplied between the third guide duct 25 and the fourth guide duct 27.
When fuel gases are discharged from between the third guide duct 25 and the fourth guide duct 27 to the outside, the fuel gases are ignited. Then, the thermal energy is generated by the combustion of the fuel gases. As described in the first embodiment, chemical reactions of the particles discharged from between the first guide duct 21 and the second guide duct 23 occur by the thermal energy generated from the combustion of the fuel gases (S40). Accordingly, new metallic or non-metallic particles are formed by using the ions, which are generated from discharge electrode 10 and discharged from the first guide duct 21, as nuclei. Naturally, the newly formed particles P are highly charged. Thus particles P are discharged to the outside under the action of the electric field, adhere to the collecting plate 70, and are colleted on the collecting plate 70 (S50).
Meanwhile, since the sheath gases are supplied between the second guide duct 23 and the third guide duct 25 as described above, the sheath gases are discharged to the ends of the second guide duct 23 and the third guide duct 25. Since the discharged sheath gases prevent the thermal energy generated through the ignition of the fuel gases from being transferred to the end of the second guide duct 23, the chemical reactions do not occur at the end of the second guide duct 23. Therefore, the chemically reacted particles do not adhere to the inner wall of the second guide duct 23, the outlet of the second guide duct 23 is not clogged. Accordingly, the reaction gases continue to be smoothly discharged.
Although the various embodiments of the present invention have been described in the above, the spirit and scope of the present invention is not limited only to the above embodiments. The specific shapes and structures shown in the above embodiments are described as only exemplified examples. In addition to the above embodiments, various modifications to the present invention may be made without departing from the spirit and scope of the claims.
As described above, according the an apparatus and method for manufacturing particles using corona discharge of the present invention, collecting efficiency of the particles can be very high and sizes of the particles to be collected can be controlled.
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/KR02/02113 | 11/12/2002 | WO | 5/11/2005 |