System for filtering airborne particles

Disclosed is a system for filtering airborne particles from an occupied space. The system permits the removal of airborne particles by manipulating both the charge and the size of the particles, thus enabling the capture of particles that most other typical filtration systems leave behind. More specifically, the system captures small airborne particles through the use of a series of electric fields, forcing them to be trapped in a series of filters or collide to form larger particles, whereby their movement and capture are subsequently governed primarily by airflow. The system controls particle behavior by utilizing specific electromagnetic fields to collide particles, capture particles, and deactivate live pathogens that get captured.

RELATED APPLICATION DATA

This application claims priority to co-pending application Ser. No. 61,695/588 filed on Aug. 31, 2012 and entitled “Advanced Filtration System for Airborne Particles.” The contents of this application are fully incorporated herein for all purposes.

TECHNICAL FIELD

This disclosure relates to a system for the filtration of airborne particles from an occupied space. More particularly, this disclosure relates to the filtration of small airborne particles from an occupied space by manipulating the charge and size of airborne particles and capturing them in a series of filters.

BACKGROUND OF THE INVENTION

Airborne particles exist in a wide variety of shapes and sizes. Aerosols are composed of either solid or liquid particles. Conversely, gases are molecules that are neither liquid nor solid and expand indefinitely to fill the surrounding space. Both types of contaminates exist at the micron and sub-micron level in air. Most dust particles, for example, are between 5-10 microns in size (a micron is approximately 1/25,400th of an inch). Other airborne contaminates can be much smaller. Bacteria commonly range anywhere between 0.3 to 2 microns in size, and viruses can be as small as 0.02 microns in size or smaller. The importance of removing these contaminates varies based upon the application. Semiconductor clean rooms and hospital operating rooms are two examples of spaces where the ability to remove contaminates is critical.

One factor complicating the removal of contaminates is that particle number density increases with smaller particle size. For example, in the typical cubic foot of outside air there are approximately 1000 10-30 micron sized particles. The same volume of air, however, contains well over one million 0.5 to 1.0 micron particles. As particle measuring instrumentation evolve they are capable of measuring deeper into the submicron range. Thus, advances in particle detection technology has confirmed that a great majority of all airborne particles are less than a micron in size. The prevalence of small particles is problematic from an air quality standpoint because small particles are hard to control and therefore hard to capture. Yet most contamination problems are caused by small particles.

Most small particles have a charge associated with them, while larger particles tend to be more neutral in charge. Thus, the movement of small airborne particles is primarily governed by electromagnetic forces, whereas the movement of large airborne particles is primarily governed by airflow. Further, small particles are also more influenced by Brownian Motion, both thermal and kinetic. However, larger particles have more mass associated with them. This is the basis of why larger particles are controlled more by the airflow generated by an HVAC system.

Particles acquire charge by three basic mechanisms. Diffusion charging occurs when particles are charged by random collisions between ions and other particles. The motion and collisions result from a process known as Brownian motion. The particle can take on multiple charges by this mechanism. Field charging occurs when rapid ion movement in an electric field causes frequent collisions between ions and particles. Finally, static electrification occurs when particles are separated from surfaces, thereby charging the particles. The factors that affect how a particle behaves in an electric field include particle size, the charge associated with the particle, and the strength of the electromagnetic field. The smaller the particle, the more it is influenced by an electromagnetic field. The more charge there is on a particle, the stronger the influence of the electromagnetic field. The stronger the electric field, of course, the more influence it has on the particle.

As discussed above, a great majority of the airborne particles found in nature are less than a micron in size. Thus, conventional air filtration systems that utilize airflow to capture airborne particles by trapping them in a filter device inevitably fail to trap smaller particles, leaving them free to circulate within an occupied space. Furthermore, the more efficient the filter in a system governed by airflow, the greater the pressure drop across the system. This pressure drop consequently decreases the efficiency of air filtration systems dependent on airflow as the primary force on airborne particles.

To overcome the difficulties associated with the capture of small particles, different particle conditioning techniques can be orchestrated together to control the transport, capture, and deactivation of particles. These conditioning tools include but are not limited to, particle ionization, particle polarization, and controlled particle colliding.

Particle ionization occurs when a particle passes through an ion field. One type of ion field is a corona field. A corona field is created when a voltage is passed through a very thin wire or a thin metal blade with a serrated edge. Upon application of the voltage, electric fields concentrate on a sharp point and on a thin edge. When the electric field is strong enough, charges are emitted to the surrounding space, thereby developing a space charge. For example, if a negative high voltage is applied to a thin wire or metal edge, electrons are emitted to the air surrounding the wire or blade. When a particle passes through this created electron field, the particle picks up, or acquires, some of the electrons and becomes a negative ion (this also applies to a positive field which produces a positive ion). In the case of a particle passing through the negative ion field (electrons) the particle becomes negatively charged, thereby allowing it's movement to be controlled by the subsequent application of another electric field. If a grid that has the same voltage applied to it as the corona grid is placed in the path of the particle, the particle will be repelled by the grid (like charges repel each other). Furthermore, if a positive wire is placed downstream from the negative wire the conditioned particle will be propelled towards this positive grid (unlike charges attract each other). This is how the trajectory of particles can be controlled using precisely controlled electromagnetic, electrostatic, and/or electrodynamic fields.

When a particle passes through a strong electrostatic field it can form a dipole, wherein one end of the particle is positively charged and the other end is negatively charged. This polarization is due to the fact that opposite charges attract and like charges repel. When a particle approaches a strong electrostatic field, such as a −15 kV field, a dipole is formed. Some of the positive charges in the particle will move toward the strong field (front of the particle) and some of the negative charges will move towards the opposite end (rear) of the particle, away from the static field (FIG. 2A). Once this occurs the particle passes through the electrostatic field. If a second electrostatic field, of the opposite potential is downstream from the first electrostatic field the particle propels toward it.

Controlled Particle Colliding performs at least two functions. First, it causes collisions between sub-micron sized particles to form larger particles, thus changing them from being dominantly controlled by electromagnetic fields to being controlled by airflow. Second, it makes particles neutral in charge. Particles will not only stay entrained in the airflow without being influenced by the electromagnetic fields in the room environment, but will not be as likely to form strong bonds with surfaces and objects in the room, even if they should come in contact with them.

Media Filter Systems—

This major class of filter system typically uses no electromagnetics in its operation. Basically this type of air cleaning device is a particle block. The particles that get to the device are filtered in the media material. In other words filtration occurs at the filter. These devices are placed in the airstream perpendicular to airflow. Airflow brings the incoming particles to the filter and the incoming particles get trapped as the air passes through the filter. This type of device depends on airflow.

When proper dielectric media material is utilized and an electrostatic field is applied across the media material, an opposite polarizing electric field is generated across the media material causing the material itself to polarize (seeFIGS. 4 and 5). Depending on the density of the media material determines the depth of penetration of conditioned particles. Optimizing the Collector and proper conditioning of particles results in efficient particle collection (and deactivation of microbes where appropriate).

Transport Mechanisms are what control the movement of particles. In every building environment there are forces present that determine these transport mechanisms. The Dominant Transport Mechanisms in a building environment are Airflow and/or Electromagnetic Fields, as described herein. Only relatively large particles, greater than a micron in size, are controlled by airflow. Smaller particles are dominantly controlled by electromagnetic fields. The smaller the particle, the more this statement becomes true.

Two equations dictate particle behavior. 1. Force equals the change in momentum of the particle (F=ma), due to airflow. 2. Charge times the electric field E (F=qE) due to electric forces in the room environment. Note 1: F is the force, m is the mass, a is acceleration, and E is the electric field. The first equation (F=ma) describes how airflow controls particle behavior and the second equation (F=qE) describes how the electric field controls particle behavior.

As is known in the art, the difficulty associated with capturing small airborne particles can be overcome by utilizing Particle Accelerated Collision Technology™ (PACT) (U.S. Pat. No. 7,175,695). PACT makes airflow the dominant transport mechanism and controls the behavior of fine particulates by creating inelastic collisions on a sub-micron level. This causes smaller particles to collide inelastically, thus becoming larger, thereby enabling any associated filtration system to easily remove these larger particles from the air. This collision process significantly improves the ability of a standard filtration system to remove and reduce indoor and outdoor generated contaminate levels.

Controlled Particle Colliding is similar to PACT, but much more compact. By combining it with the other components described herein it is made as effective as PACT. Alone, it would not be as effective due to its depth of influence being much smaller than an actual PACT system.

Also known in the art is Particle Guide Technology (PGT) (Pub. No. 2012/0085234). PGT forces particles to travel in a desired manner to a desired location, and/or a Particle Collector. The Particle Collector then traps the particles, removing them from the occupied space. PACT and PGT both utilize controlled electromagnetic fields to guide particles to a desired location. They are employed as a particle control device.

The majority of present filtration devices depend on airflow to guide particles to the filtration system. In general they are particle traps. Further, the space available in a typical HVAC system is limited. When the space that the filter is placed in is limited (in the direction of depth) the efficiency and/or pressure drop of the system can be compromised. Although great strides have been made in the efficiency of the traps, little has been done to control the particle itself. It should be mentioned that different particle conditioning techniques have been utilized individually to enhance particle filtration. However, to combine these effects in an optimized manner to control particle behavior is the goal of the present invention. By conditioning and controlling particles, the present invention takes advantage of the dominant transport mechanisms in air.

SUMMARY OF THE INVENTION

This disclosure provides a system for filtering airborne particles in an occupied space, the system comprising a particle conditioning unit; a first stage collector; and a particle collider. Another embodiment of the present disclosure includes a second stage collector positioned downstream the particle collider. Yet another embodiment of the invention includes a particle deflector system for overcoming the limitations associated with typical air filtration systems based solely on the physical capture of particles guided by airflow.

The disclosed system has several important advantages. For example, the disclosed system functions to make airflow the dominant transport mechanism of airborne particles.

A further possible advantage is that the collector system is more effective and efficient at capturing both small and large airborne particles.

Still yet another possible advantage of the present system is the capture and deactivation of health degrading organisms that interact with the filter system.

Various embodiments of the invention may have none, some, or all of these advantages. Other technical advantages of the present invention will be readily apparent to one skilled in the art.

DETAILED DESCRIPTION OF THE EMBODIMENTS

The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which embodiments of the invention are shown by way of illustration and example. This invention may, however, be embodied in many forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Like numerals refer to like elements.

The present invention relates to systems and related methods for the filtration of airborne particles in an occupied space. The various components of the present invention, and the manner in which they interrelate, are described in greater detail hereinafter.

By way of example and with reference initially toFIGS. 1A, 1B, 2A, and 2B, one embodiment of the invention comprises a system10for filtering airborne particles12in an occupied space14, the system10comprising a particle conditioning unit16including a first grid18of electrically conductive elements20and a first voltage source22, wherein a first voltage24is applied to the first grid18by the first voltage source22sufficient for creating a corona field26for ionizing airborne particles12received by the particle conditioning unit16. The particle conditioning unit16may include wires of different diameters or blades of different serrations and thickness depending on how much polarization or ionization of incoming particles12is desired to optimize collection in the first and second stage collectors28,70downstream in the system10. The larger diameter (thicker) wires polarize incoming particles forming particle dipoles. As an example, applying a negative potential on the particle conditioning unit16creates dipoles as shown inFIG. 2A. The voltage field polarity of the particle conditioning unit determines the dipole structure. The grid wires18inFIG. 2Aare of large diameter and therefore does not set up a corona field26and does not emit negative ions. As a result, the incoming particles are polarized as shown. Once the dipole is formed the particle31moves to the first stage collector28. It should be understood that depending on the strand type and thickness of each wire employed in the particle conditioning unit16, the grid wires could also be used as an ionizer. Further, the particle conditioning unit16can perform both operations simultaneously or independently depending on the wire stranding (or blade thickness configuration) of the particle conditioning unit16(seeFIG. 2B). In this way incoming particles12can be conditioned for optimum collection in the first stage collector28and the second stage collector70. Therefore, both negative ions and or dipoles can be created by the first grid18of the particle conditioning unit16.

With reference toFIGS. 1A, 1B, and 3A, one embodiment of the invention comprises a first stage collector28positioned downstream the particle conditioning unit16for receiving the ionized airborne particles30, the first stage collector28including a first particle diffuser32including dielectric fibers34; a second grid36positioned downstream the first particle diffuser32, the second grid36including electrically conductive elements20, wherein the second grid is electrically grounded38; a first collector pad assembly40positioned downstream the second grid36, the first collector pad assembly40including a first filter pad42and a second filter pad44, wherein the first and second filter pads42,44comprise fibers46of dielectric material48, and wherein the first filter pad42is less dense than the second filter pad44; and a third grid50positioned downstream the first collector pad assembly40, the third grid50including electrically conductive elements20and a second voltage source52, wherein a second voltage54is applied to the third grid50by the second voltage source52, and wherein the second voltage is of opposite polarity to the first voltage24.

The second grid36of the first stage collector28can be grounded38or set at the opposite potential of the first grid18of the particle conditioning unit16. The object is to control the trajectory of the conditioned particles30,31as they exit the particle conditioning unit16and optimize the collection of these particles. It should be noted that the type of particle least affected by the first stage collector28is a neutral (no charge associated with it) particle. In summary, the one objective is to optimize the stranding of the particle conditioning unit16so that particles are optimally charged, by creating dipoles31and/or ions30, and then capturing the conditioned particles30,31in the first stage collector28.

The first grid18of the particle conditioning unit16also sets up an electrostatic field, Ep, between itself and the second grid36of the first stage collector28. The second grid36of the first stage collector28may be grounded38or set at the opposite potential of the first grid18of the particle conditioning unit16. This becomes important for proper operation of the first particle diffuser32in the first stage collector28, which will be explained below.

The first stage collector28may be divided into five parts, including a first particle diffuser32, a second grid36, a first collector pad assembly40including first and second filter pads42,44, and a third grid50.

The First Particle Diffuser32—

Conditioned particles30,31penetrate the first particle diffuser32pad first. This first particle diffuser32pad is placed in front of the second grid36of the first stage collector28. The first particle diffuser32distributes the incoming conditioned particles30,31so they do not coat the second grid36of the first stage collector28. The first particle diffuser32forces particles to be diffused away from the second grid36of the first stage collector28, thus protecting the grid from coating with particles, which would diminish the operation of the system. This significantly extends the period between maintenance of the system. The first particle diffuser32pad has a thickness d, which is much thinner than the first collector pad assembly40of thickness L. In this way the majority of particles penetrate to the first and second filter pads42,44.FIG. 4shows the electric field, Ep, created between the particle conditioning unit16and the second grid36of the first stage collector28. This field penetrates the first particle diffuser32, thereby polarizing the dielectric media fibers34in the first particle diffuser32. The polarized field created in the first particle diffuser32pad media material is an electric (E) field in the opposite direction, Edp (seeFIG. 4). It should be noted that a first particle diffuser32pad may or may not be employed. This does not change the scope of the invention.

Second Grid36of the First Stage Collector28—

The second grid36is grounded38or at the opposite potential of the particle conditioning unit16as explained above and completes the potential difference between them (Ep). Again, Ep causes the dielectric fibers34in the first particle diffuser32to polarize creating Edp throughout the first particle diffuser32material. The second grid36also sets up an E field to the third grid50of the first stage collector28, which is at the opposite potential to the second grid36. The generated field Ec penetrates the first collector pad assembly40.

The First Collector Pad Assembly40—

The first collector pad assembly40may include two pad components, a first filter pad42(open weave pad) and a second filter pad44(closed weave pad). The two pads are composed of dielectric impregnated fibers46, or dielectric material48, that are polarized by the Ec field. The open weave structure in the first filter pad42attracts some of the incoming particles30,31and allows other particles to penetrate deeper into the second filter pad44for proper distribution and a larger surface area, and as a result, longer filter life. The velocity and charge associated with the conditioned incoming particles30,31determine the penetration depth of these particles. In a manner similar to that described for the first particle diffuser32, the field Ec polarizes the media in the first collector pad assembly40and creates an opposite field in the media Ecp1and Ecp2.

Third Grid50of the First Stage Collector28—

The third grid50of the first stage collector28is necessary to complete the potential difference across the first and second filter pads42,44. The second and third grids36,50create the electric field Ec across the dielectric material48in the first and second filter pads42,44, as explained above, thus polarizing the dielectric material48in the first and second filter pads42,44, creating field Ecp1and Ecp2shown inFIGS. 5A and 5B. When the particle dipoles31penetrate the first filter pad42they are attracted to the fibers46and form an ionic bond with the fibers46of the first filter pad42. In one embodiment of the invention, the material in the first filter pad42is less dense than the material in the second filter pad44, allowing particles to penetrate deeply into the first collector pad assembly40and into the second filter pad44. This allows for uniform penetration and long filter life. It will be noticed that Ecp1and Ecp2have the opposite field direction as Edp. This optimizes the electrostatic field in the first collector pad assembly40for efficient collecting and deactivating of particles.

It should be apparent to one skilled in the art that the system10described kills, disables, an/or deactivates pathogens or organisms, including viruses and bacteria. This anti-pathogenic activity of the system10results from the ionization and/or polarization fields established by the system10. In one embodiment of the invention, the anti-pathogenic activity of the system results from the ionization and/or polarization fields established by at least one of the particle conditioning unit16, the particle collider56, and the first and second stage collectors28,70. Thus, one possible advantage of the present system is the capture and deactivation of health degrading organisms that interact with the filter system.

With reference toFIGS. 1A, 1B, 6A, and 6B, one embodiment of the invention comprises a particle collider56positioned downstream the first stage collector28, the particle collider56including a plurality of parallel serrated blades58and a third voltage source60, the plurality of parallel serrated blades58comprising points62sufficient for emitting ionizing particles64, wherein a third voltage66is applied to the plurality of parallel serrated blades58by the third voltage source60, and wherein the third voltage continuously alternates in polarity, the third voltage sufficient for creating a switching electrodynamic field for forcing the airborne particles12to collide with one another, thereby forming larger particles68.

The particle collider56conditions and forces particles to inelastically collide with each other, thereby creating larger particles68. In one embodiment of the invention, the particle collider56consists of emitter plates spaced equally apart58,61or a wire array59system. Each plate or wire array has an alternating electric voltage66applied to it. The plates alternate at switching time T. If emitters are utilized, they preferably have sharp points62that emit ions (in the form of protons and electrons, depending on polarity) into the space in front of each emitter creating a space charge. Since each emitter has the opposite charge associated with it, incoming particles pick up the charge in the region it passes through. This section of the particle collider56is the particle conditioning section. Therefore, as particles moves into the particle collider56, they pass through the appropriate ion field set up by the emitter. The emitters emit equal amounts of positive and negative charges at a high voltage and low enough current not to generate ozone. After the particles pick up their appropriate charge(s) they enter the collision accelerator section of the particle collider56. The conditioned particles are now conditioned to be influenced by the electric fields set up between the plates of the emitters. As the particles continue to the plate area, after the sharp blades58,61, they go back and forth between the plates (as the plates alternate between voltages) and the particles collide with other opposite-charged particles, created by the conditioning section of the particle collider56, also going back and forth between the plates. Since the emitters voltage alternates particles move back and forth between plates colliding into each other forming larger particles68. When particles of opposite charge collide they form ionic bonds (inelastic collisions) and do not come apart. The exiting particles are larger than the incoming particles and are more neutral in charge. It should be noted that a wire array system, or combination of wires and plates as well as sharp point emitters, can also be employed. Also, by utilizing thin wires on the third grid50of the first stage collector28and taking advantage of the ionized particles created by the particle conditioning unit16and first stage collector28, plates or blades61alone can be used in the particle collider56to collide particles independent of conditioning serrated blades and/or wires.

To summarize, the particle collider56performs two operations, particle conditioning and particle colliding. Once the particle enters the electric field, this field becomes the dominant force on the particle. Since each particle has a net charge associated with it, generated by the particle conditioning section of the particle collider56, it is immediately attracted to the opposite charged plate (emitter). When the field switches the particle is now attracted to the other plate where it is constantly on a collision course with other, oppositely charged particle. Two particles collide and stick together (inelastic collision) making them a larger particle. Then, the larger particle moves towards the opposite charged plate. Again, the electric field of the emitters switch and the larger particle68is attracted to the opposite plate. This process continues hundreds of times until the resulting larger particles leave the particle collider56with a more neutral charge than the original particles entering the particle collider (seeFIG. 6A, 6B).

In another embodiment of the invention, controlled particle colliding is accomplished in two steps, particle conditioning and particle colliding. In the particle conditioning step, particles are conditioned with a small amount of space charge. By putting a charge on particles, they become susceptible to electrodynamic fields. Using thin serrated blades or thin wire arrays the particles entering the particle collider acquire a charge. The particle collider56emits equal amounts of positive and negative charges at an extremely low current level to avoid generating ozone. As particles pass through this section of the particle collider they pick up these charges. This makes the particles more influenced by the electrodynamic fields in the particle colliding section of the particle collider that increases their attractive force to each other, thus enhancing inelastic collisions.

In one embodiment of the invention, the particle conditioning step is followed by the particle colliding step. After the particles are conditioned they then enter the switching electrodynamic fields. Particles are accelerated and deflected, thereby enhancing Brownian motion. In this section of the particle collider56the collision process is rapidly accelerated and particles interact more rapidly than they would naturally. Both positively charged and negatively charged particles, created by the particle conditioning section of the particle collider56, go through the switching electrodynamic fields and as a result collide with each other. When they collide they collide inelastically, the applied charges on the particles form ionic bonds with other particles, and larger particles68are created. This process of colliding continues throughout the particle colliding section of the particle collider, thereby forming larger and larger particles68. These particles go into the occupied space14and continue the process of colliding with other particles, TVOCs, and gases. Smaller particles, TVOCs and gasses absorb and adsorb onto these larger particles68, that are now controlled by airflow, and get eliminated from the occupied space14because the filtration/collector system is more effective in capturing these particles.

With continued reference toFIG. 1A, one embodiment of the invention comprises a second stage collector70positioned downstream the particle collider56for receiving the larger particles68, the second stage collector70including a second particle diffuser72including dielectric fibers34; a fourth grid74positioned downstream the second particle diffuser72, the fourth grid74including electrically conductive elements20, wherein the fourth grid is electrically grounded38; a second collector pad assembly76positioned downstream the fourth grid74, the second collector pad assembly76including a third filter pad78and a fourth filter pad80, wherein the third and fourth filter pads78,80comprise fibers46of dielectric material48, and wherein the third filter pad78is less dense than the fourth filter pad80; and a fifth grid82positioned downstream the second collector pad assembly76, the fifth grid82including electrically conductive elements20and a fourth voltage source84, wherein a fourth voltage86is applied to the fifth grid82by the fourth voltage source84, and wherein the fourth voltage86is of a same polarity of the first voltage24.

Like the first stage collector28described above, the second stage collector70may include five parts. Further, the first stage collector28and the second stage collector70may share an identical construction. The second stage collector70would be configured to have an opposite field associated with it than the first stage collector28. The second stage collector70attracts remaining charged particles that escaped the other components of the system. Larger neutral particles68, formed by the particle collider56will escape the second stage collector70and go out into the occupied space14to collect other particles, including but not limited to TVOCs, gases, odors, bacteria, and viruses.

In another embodiment of the present invention and with reference toFIGS. 7A, 7B, 8A, and 8B, the particle conditioning unit16is set at a potential of −15 kV. The second grid36of the first stage collector28is grounded and the third grid50is set at a potential of +15 kV. The particle collider56utilized is the serrated blade configuration. The second stage collector70has the fourth grid74grounded and the fifth grid82at −15 kV which sets up opposite fields of the first stage collector (seeFIG. 7). The wires employed in the particle conditioning unit16are small gauge and therefore a negative ion field is generated (seeFIG. 8). The first grid is grounded creating an electric field Ep between the particle conditioning unit16and the second grid36of the first stage collector28. This field sets up an opposing polarized field Edp in the Diffuser pad that attracts incoming particles and protects the second grid36of the first stage collector28from coating. The two equations that dictate the penetration of particles into the first stage collector28are F=ma and F=(Σq)E. Σq represents the sum of the charges on the particle. Three things dictate the penetration of particles into the first stage collector: The incoming velocity of the particle, the amount of charge on the particle after leaving the particle conditioning unit16, and the mass of the particle. By taking advantage of these properties a large surface area was made out of a relatively small depth of collector material. Particles that escape the first stage collector28will enter the Particle Collider56. As explained above, this section causes particles to inelastically collide with each other forming larger particles. The particles that leave the particle collider are larger and more neutral in charge. The second stage collector70collects any remaining charged particles not captured by the first stage collector28and that pass through the Particle Collider56with a charge associated with it (inefficient collisions). The remaining particles that do escape the second stage collector70are conditioned by the Particle Collider56to clean out the occupied space14. Since these conditioned particles are larger in size and more neutral in charge they are controlled by airflow. They will return to the pre-filter and air filtration system10(advanced collector system, ACS) to be collected. It is understood by those familiar with the art that other potentials, including the opposite potential or grounding can be applied to the components of the system10and still be within the scope of the apparatus.

In yet another embodiment of the present disclosure and with reference to9A,9B,10A and10B, the particle conditioning unit16is at a potential of −15 kV. However, the electrically conductive elements20, or wires, have a larger diameter (large gauge) and do not create an ion field. The particle conditioning unit16creates a negative plane field at the grid assembly (seeFIG. 9). The second grid36of the first stage collector28is grounded and the third grid50is at −15 kV. The particle collider56utilized is the serrated blade configuration comprising a plurality of serrated blades58. The second stage collector70has the fourth grid74grounded and the fifth grid82at +15 kV to provide the opposite collection ability as the first stage collector28. As particles12enter the particle conditioning unit16they are forced to polarize due to the strong plane field set up by the −15 kV field. The dipoles formed move toward the first particle diffuser32of the first stage collector28. Since the first particle diffuser32is at the same potential as the dipoles the dipoles deflect away from the grounded second grid36in the first stage collector28.FIG. 10shows the set-up of the E fields in the first collector pad assembly40of the first stage collector28. As can be seen, the fields set up in the first collector pad assembly40are at opposite potential to the incoming dipoles and therefore have a strong attraction to them. By optimizing the thickness of the first diffuser pad32and first collector pad assembly40, and by optimizing the distances of the particle conditioning unit16and second and third grids36,50of the first stage collector28, particles penetrate the first collector pad assembly40of the first stage collector28. The incoming velocity of the particles, the strength of the dipole moment of the particles after leaving the particle conditioning unit16(amount of charge on each end of the dipole and its ability to keep the charge distribution), and the mass of the particles dictate the penetration of particles into the first stage collector28. Both the particle collider56and second stage collector70behave as described above. However the second stage collector70has the opposite potential applied for efficient collection. It should be noted that the particle conditioning unit16could have different diameter electrically conductive elements20, or wires, employed to both polarize and ionize incoming particles for the most efficient collection of incoming airborne particles12in the system10(seeFIG. 2B). Also, the applied potentials can be changed on the particle conditioning unit16and second, third, fourth, and fifth collector assembly grids36,50,74,82to optimize particle collection and deactivation efficiency without changing the scope of the apparatus. It should also be noted that the component positions in the system10could be changed without changing the scope of the apparatus.

Yet another embodiment of the present disclosure employs a No Pressure Drop Collector System. The particle conditioning unit16is set to −15 kV and a Particle Deflector88is set to 15 kV. The wires in the particle conditioning unit16have a small diameter and creates an ion field. The particle conditioning unit16creates negative ions out of incoming particles (seeFIG. 11A, 11B). The first stage collector28is placed parallel at the top and bottom of the ACS and is set up to attract and capture particles, as shown. Note by adjusting the fields in the particle conditioning unit16and Particle Deflector88the particle conditioning unit16can be utilized as a polarizer. The first stage collector28is set up as shown inFIG. 8as it is with other embodiments. The Particle Collider56utilized is the serrated blade configuration. The second stage collector70has the fourth grid74grounded and the fifth grid82at −15 kV to provide the opposite collection ability as the first stage collector28. It should be noted that the second stage collector70could also be a No Pressure Drop Collector System. As particles12enter the particle conditioning unit16they are negatively charged. The charged particles30move toward the Particle Deflector88and get deflected towards the first stage collector28, as seen in theFIG. 11. Since, the first stage collector28is identical in structure as other embodiments, except it is placed parallel to the airstream, it performs the same way as other embodiments. Particles that escape the first stage collector28will enter the Particle Collider56. As explained above, this section causes particles to inelastically collide with each other forming larger particles68. The particles that leave the Particle Collider56are larger and more neutral in charge. The second stage collector70collects any remaining charged particles not captured by the first stage collector28and that pass through the Particle Collider56with a charge associated with it (inefficient collisions). The remaining particles that do escape the second stage collector70are conditioned by the Particle Collider56to clean out the occupied space14. Since these conditioned particles are larger in size and more neutral in charge they are controlled by airflow. They will return to the pre-filter and ACS to be collected. It is understood by those familiar with the art that other potentials, including the opposite potential or grounding can be applied to the components of the ACS and still be within the scope of the apparatus. It should be noted that the particle conditioning unit16could have different diameter wires employed to both polarize and ionize incoming particles for the most efficient collection of incoming particles in the ACS (seeFIG. 2B). Also, the applied potentials can be changed on the particle conditioning unit16and collector assembly grids36,50,74,82to optimize particle collection and deactivation efficiency without changing the scope of the apparatus. It should also be noted that the component positions in the ACS could be changed without changing the scope of the apparatus. It should also be noticed that the first and/or second stage collectors28,70can be a No Pressure Drop Collector System.

Yet another embodiment of the present disclosure, the particle conditioning unit16is at a potential of −14 kV. The second grid36of the first stage collector28is +14 kV and the third grid50is at −14 kV. If a second stage collector70is utilized it has the opposite polarities in the second grid36and the third grid50, which sets up opposite fields of the first stage collector28(FIGS. 7A and 7B). The wires employed in the particle conditioning unit16are small gauge and therefore a negative ion field, or corona field26, is generated (FIG. 8). The second grid36of the first stage collector28is positive, creating an electric field Ep between the particle conditioning unit16and the second grid36of the first stage collector28, through the first particle diffuser32(if utilized). Three things dictate the penetration of particles into the PCU: the incoming velocity of the particle, the amount of charge on the particle after leaving the particle conditioning unit16, and the mass of the particle. By taking advantage of these properties a large surface area is made out of a relatively small depth of collector material. Particles that escape the first stage collector28will enter the particle collider56. As explained above, this section causes particles to inelastically collide with each other forming larger particles68. The particles that leave the Particle Collider56are larger and more neutral in charge. It is understood by those familiar with the art that other potentials, including the opposite potential or grounding can be applied to the components of the ACS and still be within the scope of the apparatus. More than one collector can be utilized and the materials used in the collector can be changed, or increased in number without changing the scope of apparatus.

In yet another embodiment of the present disclosure the particle conditioning unit16is at a potential of −14 kV. However, the electrically conductive elements20, or wires, have a larger diameter (large gauge) and does not create an ion field. The particle conditioning unit16creates a negative plane field at the first grid18assembly (seeFIG. 9). The second grid36of the first stage collector28is +14 kV and the third grid50is at −14 kV. If a second stage collector70is installed the second stage collector70has the fourth grid74grounded and the fifth grid82at +14 kV to provide the opposite collection ability as the first stage collector28(similar toFIG. 7B, employing polarizing particle conditioning units instead of ionizing particle conditioning units). As airborne particles12enter the particle conditioning unit16they are forced to polarize due to the strong plane field set up by the −14 kV field. The dipoles formed move toward the first stage collector28.FIG. 10shows the set-up of the E fields in the first collector pad assembly40by the particle conditioning unit16. As can be seen, the fields set up in the first collector pad assembly40are at opposite potential to the incoming dipoles and therefore have a strong attraction to them. By optimizing the thickness of the collector pad assemblies40,76, and by optimizing the distances of the particle conditioning unit16and grids of the first stage collector28, particles penetrate the first collector pad assembly40of the first stage collector28. The incoming velocity of particle, the strength of the dipole moment of the particle after leaving the particle conditioning unit16(amount of charge on each end of the dipole and its ability to keep the charge distribution), and the mass of the particle dictate the penetration of particles into the first stage collector28. It should be noted that the particle conditioning unit16could have different diameter wires employed to both polarize and ionize incoming particles for the most efficient collection of incoming airborne particles12in the system10(seeFIG. 2B). Also, the applied potentials can be changed on the particle conditioning unit16and collector assembly grids36,50,74,82to optimize particle collection and deactivation efficiency without changing the scope of the apparatus. It should also be noted that the component positions in the system10could be changed without changing the scope of the apparatus. In other words the particle collider56can be placed between two stages of collectors28,70and not affect the scope of the apparatus.

In yet another embodiment of the present disclosure, a No Pressure Drop Collector System is employed. The particle conditioning unit16is set to −14 kV and the particle deflector88is set to −14 kV. The electrically conductive elements20, or wires, in the particle conditioning unit16have a small diameter and create an ion field or corona field26. The particle conditioning unit16creates negative ions out of incoming particles12(seeFIG. 11). The first stage collectors28are placed parallel at the top and bottom of the system10and are set up to attract and capture particles, as shown. Note by adjusting the fields in the particle conditioning unit16and particle deflector88, the particle conditioning unit16can be utilized as a polarizer. The particle conditioning unit16is set up as shown inFIG. 8. As particles12enter the particle conditioning unit16they are negatively charged. The charged particles30move toward the particle deflector88and are deflected towards the upper or lower first stage collectors28. Since, the first stage collector28is identical in structure as the embodiments above, except it is placed parallel to the airstream, it performs the same way as in the above embodiments. Particles that escape the first stage collector28will enter the particle collider56, this section causes particles to inelastically collide with each other forming larger particles68. The particles that leave the particle collider56are larger particles68and more neutral in charge. It is understood by those familiar with the art that other potentials, including the opposite potential or grounding can be applied to the components of the system10and still be within the scope of the apparatus. It should be also noted that the particle conditioning unit16could have different diameter wires employed to both polarize and ionize incoming particles for the most efficient collection of incoming particles in the system10(seeFIG. 2B). The applied potentials can be changed on the particle conditioning unit16and collector assembly grids36,50,74,82to optimize particle collection and deactivation efficiency without changing the scope of the apparatus. The component positions in the system10could be changed without changing the scope of the apparatus. The first and/or second stage collectors28,70could be a No Pressure Drop Collector System with the other being a conventional type collector without changing the scope of the apparatus.

In yet another embodiment of the invention, the system10for filtering airborne particles12in an occupied space14further comprises a particle deflector88and a fifth voltage source90, the particle deflector88positioned downstream the particle conditioning unit16, wherein a fifth voltage92is applied to the particle deflector88by the fifth voltage source90sufficient for redirecting particles received from the particle conditioning unit16to at least one of the first stage collector28and second stage collector70.

In yet another embodiment of the present invention, the system10for filtering airborne particles12in an occupied space14, the first stage collector28and the second stage collector70are positioned perpendicular to the particle conditioning unit16.

When dielectric impregnated media material48is placed in an electrostatic field the media material48is polarized setting up an opposite electric field from the original field. The material becomes a deflector to incoming particles. The objective is to protect a grid system attached to it from coating with incoming particles.