CN113543887A

CN113543887A - Particle collector

Info

Publication number: CN113543887A
Application number: CN201880100372.8A
Authority: CN
Inventors: 威尔布罗杜萨·尼古拉斯·约翰尼斯·厄斯蒙
Original assignee: 1 Nano Co ltd
Current assignee: 1 Nano Co ltd
Priority date: 2018-10-19
Filing date: 2018-10-19
Publication date: 2021-10-22
Also published as: CA3119696A1; EP3866982A1; WO2020078573A1

Abstract

The present disclosure relates to a particle collector for collecting particles from a contaminated gas, the particle collector comprising: a drive unit for moving the gas, the drive unit comprising a drive chamber, a voltage source for generating a positive voltage, an electrically conductive drive element, wherein the voltage source is connected to the electrically conductive drive element for applying the positive voltage; a collection unit for collecting particles from the moving contaminated gas, the collection unit comprising a collection chamber for receiving the moving contaminated gas, the collection chamber comprising one or more collection surfaces for collecting particles from the received moving gas thereon; wherein the drive chamber comprises a drive chamber wall defining a drive chamber flow space for the contaminated gas, wherein the electrically conductive drive element is configured to ionize the particles and induce the ionized particles to flow in a helical motion towards the collection unit.

Description

Particle collector

Technical Field

The present invention relates to a particle collector and a method for collecting particles from a contaminated gas, such as contaminated air.

Background

Smut, fine and ultra-fine dust particles, elemental carbon, soot and 1nm structured particles in air and exhaust gas particles in traffic are sources of pollution with undesirable consequences for public health and the environment. Water droplets and mist do cause traffic problems due to obstructions or visibility. Chemical droplets may be harmful to humans and the environment due to chemical composition. Bacteria, viruses, pollen and spores directly affect public health or may be pathogenic or irritating to all life forms. To reduce the emission of such particles, eliminate fog traffic obstacles, reduce pathogenic particles, or reduce irritating particles, a number of methods and devices are known in the art. However, despite such methods, the contaminants cannot be sufficiently removed from the contaminated air.

Examples for removing ionized particles in the air above roads, streets, open places (open places) etc. are described in US 6511258 and JP 002069943. NL 2008621 and NL 207755 describe how particles are captured as a result of a high voltage ribbon discharge, or NL 2007548 describes driving particles by a high voltage discharge and capturing the particles at a collector. All these arrangements for particle capture also produce 200-300nm structured particles due to the influence of back ionization and/or plasma on the particle receptor (receiver).

Many other systems are known, such as electrostatic precipitators for reducing the fine dust content of polluted air, but all of these systems require external and additional air flow of a ventilator or similar air flow generating device to propel particles towards a plurality of charged receptacles and to collect a portion of the airborne particles in the air flow. These systems require a large amount of energy to enhance the air flow and/or remove only a relatively small fraction of airborne particles. Furthermore, only particles having a diameter of about 2.5 μm or more are filtered out of the air. Another disadvantage is that these known systems are steady state operating systems and cannot accommodate a significant increase or decrease in contaminant particle density.

US6106592 describes a gas cleaning method and apparatus for removing entrained solids and liquid aerosols from a gas stream. The gas to be treated is passed through a wet, electrostatically charged filter medium. The polarity of the electrostatic charge on the filter media is selected to enhance removal of the captured solid particles. The device has a very high demanding energy consumption. The electric field generated has a very high electric field strength of 80-800 kV/m. Further, the system is operated only as a parallel operating system in response to various numbers of devices to clean any desired gas flow. The system has a very high energy consumption and can only be modified to combine one or more parallel systems.

EP0808660a1 describes a dust collector which removes dust and/or mist contained in a gas. The system comprises charging means for charging dust and/or mist contained in the gas, spraying means for spraying the charged dust or charged mist. The system may also spray the dielectric material onto the charged dust or mist. The system comprises electric field forming means for forming an electric field for dielectrically polarizing the electric material. The system further comprises collecting means for collecting the dielectric material having collected at least a portion of the charged dust and/or charged mist. An electric field of 500kV/m needs to be applied. Disadvantageously, this system uses charged dust and mist by spraying the charged particles and/or mist into dielectric polarization, and also requires a large electric field strength.

Furthermore, some known particle collectors require a separate ventilator or similar mechanical air flow generator to move the air to be cleaned. This means that particle collectors of this type cannot be used as a stand-alone device and/or consume a relatively large amount of energy.

Disclosure of Invention

It is an object of the present disclosure to provide a particle collector and a method of collecting particles, wherein at least one of the above-mentioned disadvantages of the prior art has been eliminated.

It is an object of the present disclosure to provide a particle collector and a method of collecting particles with increased energy efficiency and/or capable of separating and collecting particles having a particle size in the range of 1nm to 100 μm, preferably 1nm to 500nm, more preferably 1nm to 100 nm.

Another object is to provide an alternative, preferably better solution to the problem of effectively removing polluting particles in the air above a geographical object. Examples of such geographical objects are selected from the group consisting of roads, parking spaces, open places and building areas or industrial factory building areas like factories, or further transfer facilities, ports, building sites, mines and other outdoor environments, or are located in indoor environments such as for example applications in offices, houses, clean rooms, hospitals, pollution installations, nurseries, high-tech factories, e.g. producing wafers, etc., inside aircraft, ships or any automotive installations, inside cargo holds of transportation installations or inside any other object forming a living environment for humans or animals. The present disclosure may also be applied in the vicinity of combustion applications, e.g. in combination with emissions of combustion units (such as vehicle emissions, aircraft emissions, ship emissions), but may also be used as a stand-alone device. The present disclosure may also be applied in the addition/replacement of other cleaning systems.

According to a first aspect, at least one of the objects may be at least partly achieved in a particle collector for collecting particles from a contaminated gas, such as contaminated air, comprising:

a drive unit for moving the contaminated gas, the drive unit comprising a drive chamber having an inlet for receiving the contaminated gas, a voltage source for generating a positive voltage, one or more electrically conductive drive elements, wherein the voltage source is connected to the electrically conductive drive elements for applying a positive voltage to the drive elements;

a collection unit for collecting particles from the moving contaminated gas, the collection unit comprising a collection chamber connected to the drive chamber for receiving the moving contaminated gas, the collection chamber comprising one or more collection surfaces for collecting particles thereon from the received moving gas;

wherein the drive chamber comprises a drive chamber wall defining a drive chamber flow space for the contaminated gas, wherein the electrically conductive drive element is distributed in and/or oriented with respect to the drive chamber flow space to ionize particles in the contaminated gas and induce the ionized particles to flow in a substantially spiral and/or helical motion in the drive chamber flow space towards the collection unit.

The drive unit may be configured to draw in ambient contaminated gas (e.g., air) via the inlet as a result of the ionized particles being induced to flow in the drive chamber. In other words, the particle collector is capable of receiving the ambient contaminated gas by accelerating the particles in the drive chamber, thereby causing the ambient contaminated gas to enter the particle collector. This can be achieved without the need for mechanical gas flow inducing means such as a ventilator. This means that the energy consumption of the particle collector can be reduced. Furthermore, in embodiments of the present disclosure, there are no mechanical devices (e.g., fans or similar devices) extending outside of the particle collector configured to force contaminated air into the particle collector, as they may, in some cases, negatively impact the separation efficiency of the particle collector: especially very small particles may drift inside the particle collector for a longer time and thus may sink less efficiently into the collecting unit.

The physical flow induced by the particle collector coincides with the flow of charged particles and partially or non-ionized particles, causing all particles to flow to the walls of the particle collector where they settle either by chemical bonding or by impact.

The required gas supply is provided by the drive unit of the particle collector. The same drive unit is also capable of imparting a rotational movement to the gas, the rotational speed of which is sufficiently large to cause a "cyclone effect". In other words, the rotational speed of the gas/particle mixture is sufficiently high to allow relatively heavy particles in the gas/particle mixture to travel in a radially outward direction towards the wall of the particle collector, while relatively light gases in the gas/particle mixture remain in the central portion of the particle collector while traveling in an axial direction, so that separation of particles from the gas can be achieved. Furthermore, the flow of ionized particles causes the ionized particles to also entrain non-ionized particles to move in a generally spiral and/or helical motion towards the collection unit. For example, the ionized particles entrain ultra-small particles (particle size between 1nm and 15nm or between 1nm and 10 nm) that are difficult to ionize, so that these ultra-small particles can also be separated and collected in a collection unit.

The drive element may be completely absent from the collection chamber to allow collection of particles on one or more collection surfaces of the collection chamber.

In an embodiment of the disclosure, the collection chamber of the particle collector comprises a collection chamber flow space connected to the drive chamber flow space, such that particles in the collection chamber flow space are substantially freely movable from the collection chamber flow space to the drive chamber flow space. The drive chamber flow space and the collection chamber flow space may be configured to allow particles to flow in the collection chamber flow space to flow at least partially inside the drive chamber flow space in a generally spiral and/or helical motion.

In an advantageous embodiment of the present disclosure, the collection chamber and/or the drive chamber are cylindrical in shape (also referred to herein as "tubular" shape). The cross-section of the cylinder may be any of circular, oval, elliptical, polygonal (including rectangular) shape. By having a substantially circular cross-section or the like, turbulent flow of particles in a Navier-Stokes state can be more easily prevented.

In an embodiment of the disclosure, the collection chamber and the drive chamber have a substantially cylindrical shape with substantially the same diameter. The collection chamber may be aligned with the drive chamber. In this way, the gas/particle mixture can flow freely from the drive chamber to the collection chamber.

In some embodiments of the present disclosure, the diameter of the collection chamber may be slightly larger than the diameter of the drive chamber. The collection chamber may be aligned with the drive chamber. In this way, the gas/particle mixture can flow freely from the drive chamber to the collection chamber.

The particle collector may be configured such that all of the one or more electrically conductive driving elements are connected to one voltage source. In these embodiments, the same voltage is applied to all of the conductive drive elements.

In other embodiments, the particle collector comprises: at least one first conductive member disposed in a drive chamber of the drive unit; and at least one second conductive member disposed in the collection chamber of the collection unit, wherein a voltage lower than the positive voltage is applied to the first conductive member and/or the second conductive member. For example, the collection chamber may comprise a collection chamber wall defining a collection chamber flow space in connection with the drive chamber flow space, wherein at least a portion of the collection chamber wall forms the at least one second conductive member. The first and/or second conductive member may be connected to ground (earth) or to a voltage source such as: the voltage source provides a lower voltage, preferably a (slightly) negative voltage, than the voltage source provided by the voltage source to the drive element of the drive unit. The voltage source of the collecting unit may be different from the voltage source of the driving unit, but in other embodiments the voltage sources have been combined into a combined voltage source configured to apply different voltages to the driving unit and the collecting unit, respectively.

In an embodiment of the present disclosure, the first conductive member is a conductive mesh (gauze) concentrically mounted in the drive chamber. The conductive member may be configured to increase a gradient of an electric field potential inside the drive chamber for enhancing a corona effect due to the one or more conductive drive elements. In a specific embodiment, both the drive chamber and the first conductive member are cylindrical in shape, wherein the first conductive member is concentrically arranged inside the drive chamber and has a smaller diameter than the drive chamber such that the conductive drive element extends in the space between the cylindrical wall of the drive chamber and the first conductive member.

Typically, the at least one first conductive member, such as a cylindrical mesh, is disposed only in the drive chamber. In some embodiments, the web may also extend to some extent into the collection chamber. The at least one first electrically conductive member is preferably electrically insulated from the inner wall of the drive chamber and from the electrically conductive drive element. The at least one first conductive member may be grounded using a separate connection to ground. In the case where the first conductive member is a mesh or mesh-like structure, it is designed to allow the gas/particle mixture to flow smoothly in the axial direction. Any small air ripples due to the mesh should not affect the primary flow of the gas/particle mixture.

The inner surface of the collection chamber may comprise one or more collection surfaces having a substantially uniform charge distribution on the inner circumferential surface of the collection chamber. As a result thereof, particles within the particle flow may settle on the collection surface, since the electric field may be substantially symmetrical in the radial direction of the collection chamber.

In some embodiments, the collection chamber wall may comprise alternately arranged second conductive and insulating members, the second conductive and insulating members alternating in the axial direction, wherein each of the members has a substantially uniform charge distribution on the inner circumferential surface of the collection chamber. Thus, the collection chamber may have a plurality of walls, at which the substantially electrically conductive portions and the substantially insulating portions are alternately arranged in the axial direction of the collection chamber. On the insulating and/or conductive wall portions, each wall portion has a substantially uniform electrical potential on the inner circumferential surface of the collection chamber. If there are a plurality of conductive wall parts in the collection chamber, the same voltage may be applied to each of these conductive wall parts, alternatively, different voltages may be applied to at least two of the plurality of wall parts. Further, the second voltage applied to the at least two conductive members in the collection chamber may be different between the conductive members. Such a configuration may, for example, allow for collection of particles of different masses and/or charge-to-mass ratios on different portions of the collection surface.

In embodiments of the present disclosure, an electrically conductive drive element is mounted to the drive chamber wall and distributed at a location along the inner surface of the drive chamber wall to move particles in the contaminated gas in a generally spiral and/or helical motion. For example, the electrically conductive drive element is positioned along a helical trajectory in the flow space of the drive chamber. However, in other embodiments, the conductive drive elements are arranged in a continuous circular pattern along the length of the drive chamber. Other patterns are also conceivable. More generally, the electrically conductive drive elements may be arranged in a repeating pattern on the inner circumferential surface of the drive chamber wall. In an embodiment, the electrically conductive drive element is oriented obliquely in a pattern relative to the inner surface of the drive chamber wall. The electrically conductive drive element should be positioned in a suitable location and suitably oriented relative to the walls of the chamber to move the particles suitably in a generally spiral and/or helical motion.

According to embodiments of the present disclosure, each of the one or more conductive drive elements may be in a sharp shape. Examples of sharp shapes are pins, needles, or similar shaped objects.

According to an embodiment of the present disclosure, the particle collector comprises an obliquely oriented guiding drive element. The drive element extends at an angle relative to the inner surface of the drive chamber wall, wherein the angle can be broken down into two orthogonal angles, wherein the first angle (θ) is in the radial direction of the drive chamber between 0 ° -89 ° (e.g. having a value of 10 ° -80 °, preferably 30 ° -60 °, more preferably a value of about 45 °) relative to the normal to the surface of the drive chamber wall, wherein the second angle is in the axial direction of the drive chamber between 0 ° -89 ° (e.g. having a value of 10 ° -30 °) relative to the normal to the surface of the drive chamber wall.

The first and second angles may be selected to orient the conductive drive element such that the electric field assumes a helical and/or spiral shape within the drive chamber. Preferably, the first and second angles orient the conductive elements such that the corona of two adjacent conductive drive elements overlap so that the corona region is continuous throughout the drive chamber without causing the drive elements to discharge to the surface of the drive chamber or to another drive element. Further, depending on the positioning of the drive elements, the first angle and/or the second angle may differ between the plurality of conductive drive elements.

Particles may be collected in a collection chamber having in part an electrically isolated wall portion, for example when the particles stick to the inner surface of the wall due to impact with the wall. Only partially ionized or neutral particles may be collected in particular in the electrically isolated part of the wall. For example, the electrically isolated portion of the wall may be configured to collect moving partially ionized or neutral particles from the drive unit, which are collected by impact due to the inertia of the particles in the particle stream.

According to an embodiment of the present disclosure, the conductive driving element, the voltage source and the conductive member are configured to ionize particles by generating one or more ionizing coronas, and/or to generate an electric wind emanating from an end of the conductive driving element by accelerating ionized particles from the conductive driving element. The electric wind may include both ionized particles and other particles.

According to an embodiment of the present disclosure, the drive chamber wall is made of a substantially insulating material. The electrically conductive drive element is arranged to protrude from the insulating material of the drive chamber wall to provide a locally positively charged surface.

According to an embodiment of the present disclosure, the conductive member of the drive unit is a conductive mesh concentrically mounted to the drive unit. The conductive member may be configured to increase a gradient of an electric field potential inside the drive unit for enhancing a corona effect due to the one or more conductive drive elements. The potential differences and geometries of the drive unit, the collecting unit and the conductive member are configured to achieve such an electric field strength in the vicinity of the ends of the conductive drive element to generate a strong corona, also preventing electrical discharge (arcing) of the conductive element. Alternatively, the conductive mesh may be a wire or another tubular shaped conductive member.

According to an embodiment of the present disclosure, the particle collector includes a guide unit for guiding the particles toward the driving unit.

According to an embodiment of the disclosure, the guiding unit comprises a conductive surface, wherein the conductive surface of the guide is connected to a voltage source, and wherein a higher positive voltage is applied to the conductive surface of the guide, wherein the higher positive voltage is a higher voltage than the positive voltage applied to the conductive driving element. The higher voltage is preferably also connected to the voltage source of the drive unit.

According to an embodiment of the present disclosure, the particle collector is configured to collect particles: the particles include one or more of coal dust, fine dust, ultra-fine dust, water and chemical droplets, mist, bacteria, viruses, spores, pollen, soot, quartz, asbestos, metal particles, elemental carbon and/or exhaust gas particles and/or other particles having diameters on the order of nanometers.

According to an embodiment of the present disclosure, the particle collector comprises a control unit for controlling one or more voltage supplies to control the acceleration induced by the electric field, thereby controlling the separation characteristics of the particle collector.

According to an embodiment of the present disclosure, the particle collector comprises a detector unit, wherein the detector unit comprises an ammeter connected to the electrically conductive driving element, a particle detector, a presence detector and/or an environment detector. The environmental detector may be at least one of a humidity sensor, a pressure sensor, a temperature sensor, a magnetic field sensor, and/or other sensors. The presence detector may detect the presence of a vehicle, animal, human, cheat, etc. if the presence detector detects the presence of an object that may be associated with the emission/generation/release of particles. The presence detector may be, but is not limited to, an optical detector, a force detector, an ultrasonic detector. The controller unit may be connected to the detector unit and configured to control the supply voltage based on data from the detector unit. The control unit may use an ammeter to determine the amount of voltage required across the conductive drive element. If increased contamination in the surrounding gas is measured, the voltage across the conductive drive element may be increased. If high humidity is measured, for example, if rain water enters the particle collector, the voltage applied to any electrically conductive components of the particle collector may be correspondingly reduced (or shut off altogether). For example, in the event that water enters the particle detector, the voltage may be turned off or reduced to prevent arcing within the particle collector. Alternatively or additionally, the controller may be configured to control the particle collector during one or more predetermined time periods during one day and/or one week and/or one month. Thus, the controller may increase the voltage over the plurality of driving elements during a period of time when a relatively high amount of pollution particles is expected to be present in the air, for example during working hours or during peak traffic hours. During periods when fewer contaminating particles are expected, the particle collector may operate at a lower voltage applied to the drive element or may be completely shut off. Furthermore, the controller may also be connected to an external input, whereby the particle collector is controlled by an external user, for example in case of a traffic jam, which may instruct the controller to increase the voltage over the driving element of the particle collector.

According to another aspect, there is provided a system comprising at least two particle collectors as defined herein, wherein two or more particle collectors are arranged in series.

According to yet another aspect, there is provided a method and/or a computer readable storage medium having thereon a computer program for performing the method for removing particles from a gas (e.g. contaminated air) by operating a particle collector as defined herein.

In some embodiments, the method may be applied to clean contaminated air in indoor and/or outdoor environments, such as in and/or near areas in and/or near any of the following: a traffic system; demisting systems in traffic along roads, highways, traffic intersections, parking lots, parking spaces, automotive vehicles, schools, outdoor campuses, houses, factories, shipping vessels, transfer areas, wet and dry bulk material transfers, storage areas, ports, airports, airplanes, docks, offices, and/or the outdoor environment of these areas; and/or areas such as applied in and/or near: mining, construction site, laboratory, technical and/or medical clean room, hospital, nursery, intensive care unit, operating room, industrial factory area like a factory, and/or the method is applied as an air cleaning system for nano-sized particles and/or larger particles in a gas stream, and/or the method is combined with droplets as a gas scrubber.

Drawings

Further features of the present invention will be set forth in the accompanying description of various exemplary embodiments. In the description reference is made to the accompanying drawings.

Fig. 1 is a schematic side view of a particle collector according to an embodiment of the present disclosure.

Fig. 2 is a schematic side view of a particle collection chamber for collecting particles.

Fig. 3 is a schematic side view of a system including two consecutive particle collectors, according to an embodiment of the present disclosure.

Fig. 4 is a schematic top view of a drive chamber of a particle collector comprising a plurality of conductive elements.

Fig. 5 is a schematic top view of a drive chamber of a particle collector comprising a conductive mesh.

Fig. 6 is a schematic side view of a drive chamber of a particle collector comprising a conductive mesh.

Fig. 7a and 7b are schematic side views of the particle flow within the drive chamber.

Fig. 8a to 8c are views of a drive chamber with one or more conductive drive elements, showing the orientation of the conductive drive elements relative to the drive chamber wall, and also showing the dominant force (mayor force) on the ionized particles in fig. 5b and 5 c.

Fig. 9 is an illustration of the drive chamber and its central axis.

Fig. 10a and 10b are enlarged views of fig. 9.

Figure 11 is an illustration of the drive and collection chambers, the outlet of the drive chamber and the inlet element of the drive chamber.

Fig. 12 is a schematic view of a particle collector arranged at an angle relative to the normal to the earth's surface, arranged so that, for example, rain water can clean the inner surface of the collection chamber.

FIG. 13 is a schematic view of a collection chamber that may be cleaned using a variety of tools.

FIG. 14 is a schematic view of a particle collector according to another aspect of the present invention.

Fig. 15A and 15B show the particle distribution of air before entering and after being discharged from a particle collector as defined herein, respectively.

Detailed Description

In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the present invention. It will be apparent, however, that the present invention may be practiced without these specific details. In other instances, well-known structures and devices have not been described in detail so as not to unnecessarily obscure the present invention.

As will be apparent to those of skill in the art upon reading this disclosure, each of the individual embodiments described and illustrated herein has individual components and features which may be readily separated from or combined with the features of any of the other several embodiments without departing from the scope of the present invention. Any recited method may be performed in the order of events recited or in any other order that is logically possible.

It is noted that, as used herein and in the appended claims, the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. It is further noted that the claims may be drafted to exclude any optional element. As such, this statement is intended to serve as antecedent basis for use of such exclusive terminology as "solely," "only," and the like in connection with the recitation of claim elements, or use of a "negative" limitation.

As defined herein, the particles in the gas (e.g., contaminated air) may be solid particles (such as coal dust, fine dust, ultra-fine dust, soot, quartz, asbestos, metal particles, elemental carbon, etc.) and/or liquid particles (e.g., droplet-like particles such as water droplets, chemical droplets, mist, etc.), including biological particles such as bacteria, viruses, spores, pollen, or virtually any particulate material.

General description

Contaminated gases such as air may include liquid particles such as water droplets and/or solid particles such as coal dust, fine dust, emission particles and/or pollen having diameters (d) as small as nanometers (i.e., d ≧ 1 nm). The present disclosure relates to removing at least some of these particles from a gas, or more particularly, to removing at least some of these particles from contaminated air.

An apparatus according to an embodiment of the present disclosure includes (at least) two stages, one for accelerating and guiding particles by electric forces and another for collecting particles. In a particular embodiment, the device comprises a drive unit and a collection unit. The drive unit may include a tube, a plurality of electrically conductive drive elements (such as pins disposed on the inside of the tube), and a grounded electrically conductive inner web. The voltage source may apply a positive voltage to the plurality of conductive drive elements, thereby causing an electric field to be generated within the drive unit due to a potential difference between the positively charged conductive drive elements and the grounded internal network. The electric field is strong enough to induce a corona effect in the drive unit near the end of the conductive drive element.

Due to the corona effect, at least some of the particles are positively ionized in an ionization region of the corona. Ionization is the result of a sufficiently strong potential accelerating electrons to a sufficiently high energy so that the accelerated electrons can ionize particles due to collisions with other electrons bound to the particles. The free electrons are also accelerated to the positively charged conductive drive element. If the free electrons are also accelerated to a high enough energy to ionize other particles, an electron avalanche occurs and the plurality of particles are (fully) ionized.

The orientation of the electric field due to the orientation of the conductive drive element causes positively ionized particles to be accelerated in a predetermined direction. The particles inside the drive unit are accelerated so that the flow of the particles takes a helical (helicol) shape and/or a spiral (spiral) shape due to the shape of the electric field. Since a plurality of particles are positively ionized, a stream of ionized particles will be produced. This flow of ionized particles will create a slip flow, thereby also attracting non-ionized particles to follow the movement of the ionized particles, thereby creating an electric wind. Due to the ionized particle flow, the particles that are not ionized can also be transported in the wind to the ionization region in the drive unit and ionized there.

In this way, the particles are mainly completely ionized at the ends of the drive unit. The ionized particles are guided in the drive unit such that the movement of the ionized particles takes a spiral shape and/or a spiral shape towards the end of the drive unit. This causes the electric wind of ionized and gaseous particles to move in a vortex towards the end of the drive unit. The speed of the electric wind preferably reaches a final speed within the drive unit. The centrifugal force on the ionized particles due to the swirling motion is counteracted by the centripetal force due to the respective component of the electric field force (electrical force) on the ionized particles in the drive unit.

The end of the drive unit is preferably attached to the collection unit. The collection unit has an electrically conductive inner surface. The collecting unit is for example another tube. In the collecting unit the centripetal force due to the electric forces is substantially low, preferably close to zero due to the absence of a positively charged driving element in the collecting unit. Thus, the ionized particles collide with the walls of the collecting unit, since the centrifugal force is not (completely) counteracted by the centripetal force of the electric field in the collecting unit.

When the ionized particles collide into the conductive surface of the collection unit, the particles adhere to the surface due to covalent bonds, chemical fixation and/or collisions.

Advantageously, particles in the contaminated air in the size range starting from the nanometer scale can be collected by the present invention. Such small particles cannot be stably ionized due to brownian motion of particles having a size of less than 10 nm. Thus, the prior art is unable to remove such small particles from the air. However, the present invention will be able to collect these particles, as these particles will be part of the electric wind in the drive unit which is continuously collected by the inner surface of the collection unit. Furthermore, these particles will cross the ionization region when transported as part of the electric wind, whereby de-ionization of these particles may continuously lead to re-ionization due to the ionization region through which these particles cross.

In this context, the term "atomization" refers to the ionization of particles or droplets having an electric dipole moment or the process of inducing an electric dipole in a contaminating particle. Both processes may be performed at a distance, e.g. the atomized particles do not adhere to the charged surface of a particle catch arrangement of a pointed needle or pin-like structure. Furthermore, in the present disclosure, positively charged ionized particles, radicals or neutral atomized particles or droplets are assumed. Negatively charged particles and droplets or negatively ionized particles and droplets tend to scavenge free radicals and positively charged particles or positively charged droplets, respectively, from the air, thereby forming neutral particles or droplets. These neutral particles and droplets may again be atomized according to the atomization principles used herein and thereby acquire an inherent charge, direction and be accelerated towards a ground source (earth source) or negatively charged surface. The particles are positively ionized due to the potential applied to the driving element in the driving unit. The ionized particles are accelerated towards the collecting unit, while the electrons (the electrons bound to the particles before being ionized) are accelerated and collected by the driving element. Even in the absence of an electric field, at least a portion of the contaminating particles and/or droplets may be positively charged, and those contaminating particles and/or droplets align and accelerate accordingly as the atomized particles or droplets. Due to the presence of the electric field, at least a fraction of the total number of contaminating particles is transported to the neutral or negatively charged surface, preferably to the negatively charged surface, in the collecting unit or particle and/or droplet collector chamber. At least a part of the non-ionized contaminating particles or droplets may be ionized by the applied electric field, so that in the attached collection chamber at least a part of the total number of these ionized particles or droplets may also be transported to a neutral or negatively charged surface, preferably to a negatively charged surface, and the reduction effect on all particles is e.g. 99%.

The voltage source configured to apply a positive voltage to the electrically conductive driving element may be a static or almost static dc power plant capable of generating, for example, at least 0.2kV/m, preferably 0.2kV-100kV, more preferably 0.5kV-45kV, even more preferably 10kV-40kV, to avoid the generation of ozone. The electric field may be in the range of 0.2kV/m-2.5kV/m, such as in the range of about 0.5kV/m-2.5kV/m or at least about 1.25 kV/m. According to one embodiment, a voltage of 1kV to 50kV (e.g., 1.5kV to 50kV, more preferably about 1.5kV to 45kV, even more preferably about 2kV to 45kV, and even more preferably 2kV to 40kV) is applied to the conductive drive element as a positive charge. This means that a positively charged voltage of 1kV-50kV (preferably 1.5kV-50kV, more preferably about 1.5kV-45kV, even more preferably about 2kV-40kV) is applied to the drive element, thereby causing a charged drive element and generating an electric field of at least 0.2kV/m positive charge (more preferably in the range of about 0.5kV/m-2.5kV/m, even more preferably at least about 1.25kV/m positive charge).

The current applied is in the range of 1 muA-1A, or 1 muA-1 mA, or even 1 muA-500 muA, most preferably between 1 muA-100 muA, or no current in the case of an electrostatic field. Advantageously, by generating an induced electrostatic field at a distance, the particles and/or droplets are ionized and subsequently settle on a collecting surface, i.e. a negatively charged surface, most preferably a near-ground surface or a through-ground grounded surface. Preferably, the charged surface is negatively charged, but the surface may be grounded or earthed. May bridge a distance of about 2cm to 30m, more preferably, ionization of contaminating particles and/or droplets may occur at a distance of 2cm to 30m as found in test field measurements. Preferably, the particle catch arrangement is arranged and the field is applied such that at least a part of the total amount of contaminating particles and/or droplets at a distance of at least 4cm (more preferably at least 0.5m, even more preferably 1m, even most preferably at least 1.5m) is ionized and attracted to a negatively charged surface (i.e. a dust chamber) almost earthed or earthed with a current of 1 mA. Due to ionization of particles and/or droplets at a distance, the particles and/or droplets are effectively charged, attracted, and trapped by the particle collector (e.g., attracted by an oppositely charged, nearly grounded, or grounded surface).

The invention advantageously provides for collecting contaminating particles and droplets that will be charged and guided in an electric field, and furthermore, the particle velocity can be increased by increasing the voltage while keeping the current constant. Alternatively, the particle velocity can be slowed by lowering the voltage while keeping the current constant. The electric field configuration, particle direction and particle velocity are such that particles and/or droplets in the electric field will move and deposit at the oppositely charged surface of the particle collector. In this way, particles and/or droplets are collected and removed from the contaminated air, for example: polluted air above roads, open places and building areas or industrial factory areas such as factories, or in addition transfer facilities, ports, construction sites, and other outdoor artificial environments; or contaminated air located in interior applications, such as contaminated air in offices, houses, clean rooms, hospitals, contaminated equipment, nurseries, high-tech facilities, contaminated air located inside aircraft, ships or any automotive equipment, or contaminated air located inside any other object forming a living environment for humans or animals; and contaminated air located in household appliances such as kitchen hoods, vacuum cleaners, leaf blowers, hand dryers, hair dryers, air pumps, bathrooms, bathroom ventilation systems, mirror and window cleaning (i.e. wet, obscured vision), clothes dryers, music or other wet affected instruments (interior drying conditioning), computer cooling, air cooling and heating cycles, and all other internally applied air circulation systems. Furthermore, the installation can be in places where droplet removal can be applied indoors as a dehumidification system, such as, in examples, kitchens, bathrooms, washrooms, humid storage and crawl places (cellars, basements and attics, storage sheds, boxes and places), garages and workshops.

Detailed description of the drawings

Referring now to the drawings, in which several exemplary embodiments of particle collectors are shown. Fig. 1 illustrates a particle collector according to an embodiment of the present disclosure. The particle collector 1 comprises a drive unit 3, which drive unit 3 is configured to cause particles 2 from the ambient contaminated air to be sucked into the particle collector (flow as indicated by arrow 12) due to a slip stream generated by the flow of ionized particles within the drive unit 3, as will be explained below. The particle collector 1 further comprises a collecting unit 4 connected to the drive unit 3 (including embodiments in which the collecting unit 4 is integrally formed with the drive unit 3). The collecting unit 4 is configured to allow collecting at least a part of the particles 2 and to discharge (clean) air (indicated by arrow 13) from which the collected particles have been removed. A particle flow is generated in the drive chamber 10 of the drive unit 3. In the drive chamber 10, a plurality of conductive drive elements 6 are mounted, for example by mounting the conductive drive elements 6 to the inner surface of the wall 24 of the drive chamber 10. Preferably, the wall 24 is made of an insulating material. The electrically conductive drive element is arranged at the inner surface of the insulated drive chamber wall 24 or is arranged to pass through the drive chamber wall 24 such that the free outer end of the electrically conductive drive element 6 extends inside the drive chamber 10.

The drive element 6 is connected to a voltage source of a voltage supply 5(voltage supply). The voltage source is configured to apply a positive high voltage to all conductive drive elements 6. To this end, all of the conductive drive elements 6 are electrically interconnected so that a voltage applied to one of the conductive drive elements is also applied to the other conductive drive elements. In other embodiments, the conductive drive elements 6 are individually connected to a voltage source.

Due to the voltage applied to the conductive drive element 6, an electric field is generated within the drive chamber 10, more specifically within the particle flow space defined within the chamber walls. The electric field accelerates the particles from the drive chamber 10 towards a collection chamber 11 of the collection unit 4, as will be explained below.

The net charge on the conductive drive element 6 connected to the positive voltage source resides on its outer surface and tends to concentrate more around the (sharp) free end of the conductive drive element than in the rest of the conductive drive element. The electric field generated by the charge on the conductive drive element 6 is large enough (i.e., when the electric field strength exceeds a corona discharge initiation voltage (CIV) gradient) to ionize the gas (e.g., contaminated air) surrounding the free end. The ionization of the nearby air molecules results in the generation of ionized air molecules having a positive polarity that is the same as the polarity of the charged free end of the conductive drive element 6. Subsequently, the electrically conductive drive element 6 will repel the positively charged ion cloud and the ion cloud will start to expand due to the repulsion between the ions themselves. This repulsion of ions creates an electrical "wind" (also referred to as a "corona wind" or "ionic wind") emanating from the free outer end of the electrically conductive drive element 6.

The corona discharge ionizes the gas molecules and causes the ionized gas molecules to move in the direction of the applied electric field. Furthermore, the ionized gas molecules are not only set in motion, but they also entrain other particles (e.g., very small particles, such as in the range of 1nm to 10nm in diameter). This results in a flow of gas molecules in a direction determined by the distribution of the conductive drive element 6 in the drive chamber 10 and their individual orientation with respect to the drive chamber wall. No additional devices, such as mechanical pumps, are required to generate the gas flow and the particle collector requires little maintenance and is not prone to wear.

Furthermore, when the electrically conductive drive element 6 is positioned along the inner surface of the drive chamber wall 24 along an imaginary helical line, the gas will not only advance in the axial direction, but will also be forced to rotate. The axial movement, combined with the rotational movement, causes the gas to flow in a substantially helical and/or spiral-shaped motion towards the discharge end of the drive unit 3. This rotational movement of the gas makes it possible to separate the particles 2 from the rest of the gas, similar to the operation of a separation cyclone.

Referring to fig. 1, the voltage supply 5 is connected and controlled by a controller 30. The controller 30 may also be connected to a detector unit 31, which detector unit 31 may comprise a plurality of detectors. The number of detectors of the detector unit 31 may comprise at least one of an ammeter, a particle detector, a humidity sensor, a pressure sensor, a temperature sensor, a magnetic field sensor, for example. Although the detector unit 31 is shown as a separate unit, the detector unit 31 may also be combined with the controller 30 in one unit. Furthermore, in the case of an ammeter, the detector unit 31 may also be included in the connection from the voltage supply 5 to the plurality of conductive driving elements 6. The current meter may measure the total amount of current used in the particle collector 1, which information may be used by the controller 30 to control the voltage source 5 and thus the electric field within the drive chamber 10 accordingly.

Due to the orientation and arrangement of the plurality of electrically conductive drive elements 6 in the drive chamber 10, the particle flow within the particle flow space defines a substantially spiral and/or helical movement in the drive unit 3, which will be explained in fig. 7A-7B and 8A-8C. Thus, the flow of particles from the drive chamber 10 to the collection chamber 11 also has a substantially spiral and/or helical movement. However, the electric field generated by the plurality of electrically conductive drive elements 6 present in the drive chamber 10 does not provide a sufficiently large electric field component in the radial direction of the collection chamber 4 to completely counteract the centrifugal force generated by the spiral and/or helical movement of the particle flow. Thus, the particles 2 will hit the inner surface of the wall of the collection chamber 11 and be collected on the inner surface of the wall of the collection chamber 11.

In fig. 2, the inner surface 8 of the wall of the collection chamber 11 is shown according to an embodiment of the present disclosure. One or more conductive members 7 may be formed on the wall of the collection chamber or, as shown in figure 2, the entire wall of the collection chamber 11 forms the conductive member. In any case, the inner surface 8 comprises an electrically conductive surface 7, which electrically conductive surface 7 is connected to a voltage source providing a potential which is lower than the positive potential applied by the supply voltage 5 to the electrically conductive drive element 6 of the drive unit 3. Alternatively, the conductive surface 7 may be directly grounded (i.e., grounded). In embodiments of the present disclosure, the electric field lines from the plurality of conductive drive elements 6 may be directed at the conductive surface(s) 7 of the collection chamber 4, thereby accelerating the charged particles towards the conductive surface(s) 7 of the collection chamber 4. In other embodiments (to be described later), the electric field lines are (also) directed to one or more (further) conductive members arranged inside the drive chamber 19 of the drive unit 3.

The conductive material of the collection chamber 11 may be of resistivity 1 x 10^-7Omega/m (at 20 ℃) or less. Preferably, the resistivity is 1 × 10^-9Material of Ω m (at 20 ℃) or less, more preferably, resistivity of 1 × 10^-8Material of omega m (at 20 ℃) or less, even more preferably, a resistivity of 1 x 10^-7Omega m (at 20 ℃) or less.

Fig. 3 shows a system according to an embodiment of the present disclosure, wherein a plurality of particle collectors 1 are arranged in series. In the figure the particle collectors are shown arranged at a mutual distance, but in practice the particle collectors may also be connected to each other. In this system, a first particle collector 1 may collect a majority of the particles 2 in the contaminated air, and a second particle collector 1 may further collect a portion of the remaining particles.

Fig. 4 is a schematic top view of the drive chamber 11, wherein the inner wall comprises a plurality of electrically conductive drive elements 6. The conductive drive elements 6 are disposed in or on the inner surface of the drive chamber 10 at a mutual distance χ in the axial direction and extend through the drive chamber wall 24 into the drive chamber particle flow space. The plurality of electrically conductive drive elements 6 are arranged and oriented such that the particle stream is in a substantially spiral and/or helical motion. Furthermore, the plurality of conductive drive elements 6 and the positive high voltage applied thereto are configured to cause a corona effect in the drive chamber particle flow space. The corona generated causes the particles 2 in the contaminated air to be substantially ionized, preferably completely ionized. In some embodiments of the present disclosure, the mutual distance χ in the axial direction may be constant for the plurality of conductive drive elements 6 in the drive chamber 10. In other embodiments of the present disclosure, the mutual distance χ in the axial direction may vary between the plurality of conductive drive elements 6 in the drive chamber 10, e.g., χ may increase downstream of the particle flow and/or χ may decrease downstream of the particle flow. However, there is a minimum mutual distance χ_minFor this reason, all χ must be greater than or equal to χ_min. Minimum mutual distance χ_minMake at x_minHereinafter, discharge will occur between the driving elements. For example, χ may be increased downstream of the particle stream, thereby reducing the number of drive elements required to generate the particle stream. However, it is preferred to maintain a constant χ, since thereby a constant acceleration of the particles 2 is achieved in the axial direction of the drive chamber.

The inner surface of the wall of the drive chamber may be made of an insulating material, such as Polytetrafluoroethylene (PTFE) or teflon. The drive element may be formed by a sharp element, such as a pin, needle, pointed object, etc., and may be made of an electrically conductive material, such as metal (brass), that has penetrated the insulating walls of the drive chamber (see fig. 10A and 10B). Due to the corona discharge on the sharp drive elements and due to the arrangement of the sharp drive elements in a spiral pattern or in a plurality of consecutive circular arrangements, the contaminant particles 2, such as solid particles and/or droplets, will be accelerated and guided according to the electric field lines upon ionization, resulting in a high speed swirling movement of the solid particles and/or droplets. The velocity of solid particles and/or droplets in the swirling turbulence is related to the high voltage level attached to the sharp drive element and thus to the intensity of the corona discharge.

Fig. 5 and 6 are a schematic top view and side view of the drive chamber 10 of the drive unit 3 of the particle collector according to another embodiment. In this embodiment, the conductive member is disposed inside the driving chamber 10. More specifically, if the drive chamber 10 (and the collection chamber 11) is a tube (wherein the cross-section of the tube may be circular, elliptical or polygonal in shape, such as a cylindrical tube), the electrically conductive member may also be a tube. The tubular conductive member may be arranged concentrically inside the tubular drive chamber 10 and have a diameter smaller than the diameter of the drive chamber 10. The conductive member may be a conductive tubular mesh 9, as shown in fig. 5. In a preferred embodiment, the diameter of the conductive member 9 is such, relative to the diameter of the drive chamber 10, that (the free end of) the conductive drive member 6, which extends radially inwards from the inner surface of the drive chamber wall 24, extends in the space between the drive chamber wall 24 and the conductive member 9. More specifically, the radial distance between the free end of the conductive driving member 6 and the conductive member 9 may be as small as χ_minOf the order of magnitude (or greater) to prevent electrical discharge between the drive member 6 and the conductive member 9, while still achieving a particularly strong and uniform corona. Due to the drive chamber 10 being tubular, e.g. cylindrical in shape, the electric field within the drive chamber 10 may be relatively uniform compared to when the drive chamber 10 has a non-rotationally symmetric cross-section, such as e.g. a triangular cross-section. Thus, due to the relatively uniform electric field within the drive chamber 10, electrical discharge between the drive elements 6 may be more easily prevented in the generally cylindrical drive chamber 10.

The conductive member 9 in the drive chamber 10 is grounded (i.e., earthed) or can be coupled to a voltage source, such as the voltage supply 5, that provides a voltage that is lower than the voltage applied to the conductive drive element. Alternatively, the conductive member 9 may be directly connected to the ground. The conductive member 9 is arranged to increase corona effects in the drive chamber 10, to reduce the risk of undesired discharges towards other surfaces, such as the walls of the drive chamber or the collection chamber or adjacent conductive drive elements, and/or to provide a more uniform electric field. This may increase the acceleration experienced by the particles 2 inside the drive unit 3, thereby increasing the separation efficiency of the particle collector. Furthermore, the conductive mesh 9 may protect the plurality of conductive drive elements 6 from objects or large particles that may be detrimental to the arrangement of the plurality of conductive drive elements 6. The conductive mesh 9 may also be configured such that, for example, by having a generally open structure through which air flow may flow relatively unimpeded, resistance to air flow within the drive chamber 10 is minimized. Thus, the air flow may flow through a substantial part of the flow space within the drive chamber 10.

Fig. 7A shows a stream 14 of convoluted particles within the drive chamber 10 (i.e. where the particles flow through the drive chamber 10 with varying absolute radial distances from the centre of the axis of the drive chamber 10) and the convoluted particle stream 14 is configured to settle the charged particles 2 (i.e. solid particles and/or charged droplets). Due to the air flow generated in the drive chamber 10, the particles 2 will be accelerated towards the collection chamber 11, i.e. in both the axial and radial direction of the drive chamber 10. Similar to the spiral movement 15 in fig. 7B, the air flow from the drive chamber 10 will flow into the collection chamber 11 in a substantially spiral movement, i.e. maintaining a substantially constant absolute radial distance from the centre of the axis of the drive chamber 10. However, due to centrifugal and/or electric forces acting on the contaminating particles, the contaminating particles will collide with the collecting surface 8 of the collecting chamber 11.

Depending on the velocity of the particles, the particles 2 may flow according to a substantially spiral trajectory within the drive chamber 10 as shown in fig. 7A, or according to a substantially spiral trajectory within the drive chamber 10 as shown in fig. 7B. If the velocity of the particles is low, it may be accelerated by a component in the radial direction of the drive chamber 10. If the velocity of the particles is kept constant (i.e. the centripetal force due to the electric field inside the drive chamber 10 is equal to the centrifugal force acting on the particles), the particles may move in a substantially helical trajectory in the drive chamber 10. Thus, an exemplary particle may follow a trajectory: when the particles have been accelerated by the electric field in the drive chamber 10, the trajectory is first substantially spiral and then substantially spiral.

The swirling outward movement of the particles 2 due to the centripetal force merges with the electric force acting on all these particles 2. The charged solid particles 2 and/or charged droplets will settle through covalent chemical bonds, while the other particles 2 and/or droplets join the charge and settle by impact. More specifically, upon impact with the surface of the collection chamber of the collection unit, the particles 2 may settle due to chemical bonding, covalent bonding fixed by van der waals forces, or bonding due to the impact itself. Only a small amount of particles 2 and/or droplets may escape, preferably no particles 2 and/or droplets may escape. This stage of collecting the particles may have resulted in a 99% reduction in the number of solid particles 2 and/or droplets amounting to 1nm or more.

Over time, the collection chamber 11 may become filled with solid particles 2 and/or liquid droplets, which solid particles 2 and/or liquid droplets can be easily removed by scraping them off or by dissolving settled particles (e.g. in any type of alcohol) and washing them off. In the case of cleaning by liquid, the collection chamber 11 may be oriented obliquely downwards, so that the collected liquid can flow out under the effect of natural gravity and can be collected in a gutter into any container or tub, as will be further explained in connection with fig. 12.

In another embodiment, the particle collector may be used to clean various types of gases that may be dissolved in an aqueous environment. Droplets may be generated in a gas by: a spraying system (e.g., a high pressure nozzle system) is used to produce tiny water droplets, or an electrospray system is used for spraying water droplets into airborne tiny liquid droplets, or any other evaporation system that produces small water droplets. In case of collecting water droplets, it is preferred to capture the water droplets on a mesh-like arrangement or on a solid conductive sheet material. For this reason, rain or mist may deposit on the surface and flow off the surface due to gravity, thereby washing off the conductive surface or mesh. The inner surface of the collecting surface is arranged at an angle of 0-90 deg., preferably between about 10-80 deg., relative to the direction of gravity. All water and liquid contaminants may be collected under the collection unit, for example in a gutter. Instead of or within the grooves, an adsorbent, such as charcoal, zeolite, porous alumina, or the like, may be provided for adsorbing droplets or chemical liquids that move downward due to gravity. Thus, in a specific embodiment, a sorbent is provided, which is arranged to collect at least a part of the particles 2 or dissolved contaminants in liquid water or any other chemical liquid or water. If the adsorption capacity is reduced too much, such an adsorbent may be replaced with another adsorbent. For example, such an operation may be performed periodically.

To induce a particle flow that moves in a generally spiral and/or helical shape, a plurality of conductive drive elements 6 may be arranged in a helical shape along the inner surface of the drive chamber wall 24, as shown in fig. 8A. In this figure, the axial direction X and the direction perpendicular thereto (Y, Z) are shown. The orientation of the plurality of conductive drive elements 6 is further illustrated by fig. 8B (XZ plane) and 8C (YZ plane). The plurality of conductive drive elements 6 are arranged at an angle relative to the normal 16 to the inner surface of the drive chamber wall 24. This angle can be decomposed into two orthogonal angles theta and theta

Wherein the content of the first and second substances,

is the angle of the conductive drive element 6 in the axial direction X of the drive chamber 10 relative to the normal 16 to the inner surface of the drive chamber wall 24. The other angle theta is in the radial direction of the drive chamber 10.

Fig. 8B shows the angle of the conductive drive element 6 with respect to the normal 16 in the XZ plane

Due to this angle of the conductive drive element 6, the particles 2 are accelerated substantially in the direction of the collection chamber 11. Preferably, all conductive drive elements 6 are at the same angle

And (4) arranging. In some embodiments, the angle between the conductive drive elements 6

May be different. For example, since the particle flow is sufficiently accelerated in the axial direction X, the angle is

It may decrease in the direction of the collection chamber 11, so that the velocity in the direction X does not have to be increased. Angle of rotation

Has a value of

Preferably in the interval of

More preferably, an angle

Equal to 45 deg..

Fig. 8C shows the angle θ of the conductive drive element 6 with respect to the normal 16 in the YZ plane. Due to this angle of the conductive drive element 6, the particles 2 are accelerated in a substantially circular direction in the YZ-plane. Preferably, all conductive drive elements 6 are arranged at the same angle θ. The value of the angle theta is in the interval 1 DEG < theta < 89 DEG, preferably in the interval 10 DEG < theta < 80 deg.

In fig. 8B, the length L of the portion of the conductive drive element 6 extending from the drive chamber wall 24 into the drive chamber particle flow space is also shown. This length L may not correspond to the total length of the conductive drive element 6, since a portion of the conductive drive element 6 extends through the drive chamber wall 24.

Angle θ of orienting conductive drive element 6 and

so that the particles 2 are accelerated in the drive chamber 10 for inducing a particle movement in a substantially spiral and/or helical movement. Further, L, θ and

preferably such that the corona of two adjacent conductive drive elements 6 overlaps such that the corona region is continuous throughout the drive chamber 10 without causing a discharge of the drive element 6 to the surface of the drive chamber 10 and/or another drive element 6.

Fig. 8B and 8C also show the main forces acting on the ionized particles 2 in the drive chamber 10 of the particle collector 1. Although the ionized particles 2 are contained within the particle flow space of the drive chamber 10, two main forces (electric force F and centrifugal force Fc) are associated with the ionized particles 2 in the particle flow. The electric force F can be decomposed into three orthogonal vectors Fx, Fy, and Fz. The axial component Fx of the electric force accelerates the ionized particles in the direction of the collection chamber 11. The force vectors Fy and Fz at least partially cancel the radially directed centrifugal force Fc. If there is a net radially outwardly directed force acting on the particles, the particles will propagate towards the drive chamber wall 24. Because of the increased proximity to the conductive drive element 6, ionized particles closer to the drive chamber wall 24 will typically experience a larger electric force F due to the electric field induced by the conductive drive element 6. Preferably, an equilibrium is reached between the inwardly directed radial component of the electric force and the radially outwardly directed centrifugal force Fc within the particle flow space of the drive chamber 10. The particles 2 that are not ionized (or partially ionized) will flow radially outwards due to the lack of (sufficient) electric field forces acting on them. As a result, the particles 2 move towards the ionizing corona generated by the plurality of conductive driving elements 6. In the vicinity of the ionizing corona, these particles 2 may be ionized, preferably completely ionized.

In the collection chamber 11, the balance between the radial forces is changed due to the fact that: the radial component of the electric field force F is significantly reduced, preferably close to 0N, even more preferably reversed due to the absence of the plurality of conductive drive elements 6 and the presence of the conductive surface 7 of the collection chamber 11. These ionized particles 2 thus travel in a radial direction towards the collecting surface 8 and collide with the collecting surface 8 of the collecting chamber 11.

Fig. 9 is a diagram of the drive chamber and its central axis, in which figure the helical trajectory of the plurality of drive elements 6 is also shown. Each of the plurality of electrically conductive drive elements 6 protrudes through the drive chamber wall 24 and is connected to the voltage source 5. As can be seen from fig. 9, a plurality of electrically conductive drive elements 6 may be arranged on the drive chamber 10 to achieve a relatively constant acceleration of the ionized particles 2. The large number of conductive driving elements 6 may also ensure a sufficiently large ionization area due to the corona effect generated by the conductive driving elements 6 and the voltage applied thereto.

Fig. 10a is an enlarged cross-sectional view of the drive chamber 10 as in fig. 9, showing a plurality of conductive drive elements 6 arranged in a helical track with the drive chamber wall 24 protruding. The figure shows that the conductive drive element 6 has the same orientation with respect to the drive chamber wall 24 on either side as shown. In fig. 10B, it is also shown that these conductive driving elements 6 are connected to a voltage source 5. All conductive driving elements 6 are connected to one voltage supply 5. Thus, the voltage over all conductive drive elements 6 is therefore substantially the same.

An exemplary shape of the conductive driving element 6 is a pin as in fig. 10B. The conductive drive element 6 may have other pin-like or needle-like shapes with a pointed end for inducing a corona effect in the particle flow space of the drive chamber 10. The conductive drive element 6 is made of a conductive material having a low resistivity, for example, a metal such as gold, silver, copper, brass (messing), or other conductive material.

Fig. 11 is an illustration of the drive chamber 10 and the collection chamber 11 connected to the drive chamber via the outlet 17 of the drive chamber 10. The drive chamber 10 includes an inlet 18. The inlet 18 may comprise a mesh for preventing unwanted objects from entering the particle collector 1. The drive chamber 10 may be mounted to the collection chamber 11 by using at least two flanges attached to the connecting sides of the two chambers. These flanges may enable relatively easy mounting and dismounting of the collection chamber 11 from the drive chamber 10, which may be advantageous for e.g. maintenance and/or cleaning of the particle collector, and/or more specifically maintenance and/or cleaning of the collection chamber 11. The flanges may be mounted to each other using, for example, a set of bolts (not shown for simplicity).

According to some embodiments of the present disclosure, the outlet 17 of the drive chamber 10 arranged between the drive chamber 10 and the collection chamber 11 may comprise an electrically conductive member, such electrically conductive member may for example be a mesh as shown in fig. 11. The electric field generated by the plurality of conductive drive elements 6 may be directed towards the conductive member. Alternatively, or in addition, the outlet 17 may comprise a mesh having a coating thereon, for example in the form of a metal coating of titanium or titanium dioxide which acts as a NOX catalytic layer when irradiated with the UV spectrum to enhance the chemical conversion of NOX to harmless nitrogen dioxide. Alternatively, the outlet 17 may provide an unobstructed passage from the particle flow space of the drive chamber 10 to the particle flow space of the collection chamber 11.

Fig. 12 is a schematic view of a particle collector 1, which particle collector 1 is arranged at an angle γ with respect to the normal 19 to the earth's surface. To clean the collection surface 8 of the collection chamber 11, the particle collector 1 may be configured to allow water 20 to enter the particle collector 1. The particle collector may be arranged at an angle of 0 ° < γ < 90 °, to allow e.g. rain water to enter the particle collector 1 and thus at least partially clean the collecting surface 8 and/or drive the chamber 10 by flushing at least some of the collected particles 2 from the collecting surface 8.

In such an embodiment, it may be preferred to arrange the drive unit 3 at a higher position than the collection chamber 4, since the generated particle flow may thus be in the direction of gravity. Furthermore, ionized and/or contaminating particles may often be located above the earth's surface. Therefore, it is preferable to make the entrance of the driving unit 3 slightly higher. Furthermore, if the particle collector is cleaned by e.g. rain water 20, the collected particles may be left in the collection chamber 4, and thus, if these collected particles are released by the rain water 20, it is preferred that these released particles are discharged from the particle collector without passing through the drive unit 3.

Fig. 13 is a schematic view of a particle collector 1 with various tools that can be used to clean the collection chamber 11. For example, the tool may comprise scraping means 21 for scraping collected particulate matter from the collection surface 8 of the collection chamber 10. The manual scraping device 21 is for illustrative purposes only; the scraping device is not limited to the shown tool. The scraping device may also be incorporated as an automatic scraping mechanism for removing particulate matter from the particulate collector 1.

Other cleaning tools 22 may include, for example, a cleaning liquid that may be applied to the collection surface 8 of the collection chamber 10 in various ways. The example shown in fig. 12 is an alcohol-based solution with a wiping device 22. The wiping means may be a cloth for removing collected particulate matter from the collection chamber 11.

In some embodiments, the collection chamber 11 may be a modular chamber that is detachable from other components of the particle collector 1 to be replaced by a collection chamber 11 of particulate matter that is not collected. The collection chamber 11 that is replaced may be a new collection chamber 11 or the same collection chamber 11 after cleaning, which is detached from the other parts of the particle collector 1 when said cleaning is performed.

Fig. 14 is a schematic view of a particle collector 1 according to another aspect of the present disclosure. The particle collector may also use a guiding unit 23 configured to generate an electric field, which is thereby capable of atomizing the particles 2 at a distance and guiding these particles 2 towards the driving unit. The guiding unit 23 for example comprises a first surface as disclosed in EP1829614 (which is incorporated herein by reference). Atomizing the particles 2 at a distance requires that the surface of the guiding means 23 is also connected to the supply voltage 5, the controller unit 30 and/or the detector unit 31. The voltage applied to the surface of the guiding unit 23 is a higher voltage applied to the conductive driving element 6, thereby guiding the positively ionized particles to the driving chamber 10.

The guiding unit 23 may be arranged on the other side of the geological object than the drive unit 3 and the collecting unit 4. Thus, particles 2 in the polluted air above such geological object may be atomized and/or accelerated towards the drive unit 3 to be collected in the particle collector 1. Such geological objects may be, for example, roads, railways, mines (entrances), parks, open-air sites and/or other (public) spaces.

Fig. 15A and 15B show the test results of the performance of the particle collector 1. Fig. 15A shows the particle distribution in the polluted air 41, and fig. 15B shows the particle distribution of the cleaned air 42 after the particle trapping arrangement has been activated. Particle distribution in air was measured using a 32 channel aerodynamic particle counter (TSI condensation particle counter 3775N-butanol drive) for measuring particle distribution of airborne particles having kinetic diameters in the range of 4nm-20 μm. Particles having a diameter in the range of 4nm-523nm were classified in the first channel denoted "< 523" in fig. 15A and 15B.

Fig. 15A shows the particle distribution in the polluted air 41 before the particle collector 1 is activated. The size distribution of the particles (x-axis) is given in units of μm in the range 523nm-20 μm and as the number of particles counted (y-axis) in the range between 0 and 140.000 particles per cubic centimeter of air. Fig. 15B shows the particle size in the same scale (x-axis) as fig. 15A, but with a particle number count (y-axis) in the range between 0 and 100 particles per cubic centimeter of air. As can be seen from the difference between fig. 15A and fig. 15B, the number of particles is greatly reduced. These test results show a greater than 99% reduction in contaminating particles.

Although the foregoing invention has been described in some detail by way of illustration and example for purposes of clarity of understanding, it will be readily apparent to those of ordinary skill in the art in light of the teachings of this invention that certain changes and modifications may be made thereto without departing from the scope of the appended claims.

Claims

1. A particle collector for collecting particles from a contaminated gas, such as contaminated air, comprising:

a drive unit for moving the contaminated gas, the drive unit comprising a drive chamber having an inlet for receiving the contaminated gas, a voltage source for generating a positive voltage, one or more electrically conductive drive elements, wherein the voltage source is connected to the electrically conductive drive elements for applying the positive voltage to the drive elements;

a collection unit for collecting particles from the moving contaminated gas, the collection unit comprising a collection chamber connected with the drive chamber for receiving the moving contaminated gas, the collection chamber comprising one or more collection surfaces for collecting particles thereon from the received moving contaminated gas;

wherein the drive chamber comprises a drive chamber wall defining a drive chamber flow space for the contaminated gas, wherein the electrically conductive drive element is distributed in and/or oriented with respect to the drive chamber wall to ionize particles in the contaminated gas and induce the ionized particles to flow in a substantially spiral and/or helical motion in the drive chamber flow space towards the collection unit.

2. The particle collector of claim 1, wherein the drive unit is configured to draw in ambient contaminated gas via the inlet as a result of the ionized particles being induced to flow in the drive chamber.

3. The particle collector of claim 1 or 2, wherein there is no drive element in the collection chamber to allow particles to be collected on the one or more collection surfaces of the collection chamber.

4. The particle collector of any one of claims 1 to 3, comprising at least one first conductive member disposed in the drive chamber of the drive unit and at least one second conductive member disposed in the collection chamber of the collection unit, wherein the voltage applied to the first and/or second conductive members is lower than the positive voltage.

5. The particle collector of claim 4, wherein the first conductive member is a conductive mesh concentrically mounted in the drive chamber, wherein the conductive member is configured to increase a gradient of an electric field potential inside the drive chamber for enhancing a corona effect due to one or more conductive drive elements.

6. The particle collector of claim 4 or 5, wherein both the drive chamber and the first electrically conductive member are cylindrical in shape, wherein the first electrically conductive member is concentrically arranged inside the drive chamber and has a smaller diameter than the drive chamber such that the electrically conductive drive element extends in a space between a cylindrical wall of the drive chamber and the first electrically conductive member.

7. The particle collector of any one of the preceding claims, wherein the drive element is arranged to provide an electric force acting on particles in the drive chamber when a positive voltage is applied, the electric force having: an axial force component for moving the particles in the direction of the collection unit; and a radially inward force component that creates a centripetal force acting on the particle for maintaining the moving particle in a helical motion.

8. A particle collector as claimed in any one of the preceding claims wherein the collection chamber includes a clean gas outlet arranged for exhausting gas from which the collected particles have been substantially removed.

9. The particle collector of any preceding claim, wherein the drive chamber and the collection chamber are spatially separated.

10. The particle collector of any preceding claim, wherein the drive chamber and the collection chamber are directly adjacent to one another.

11. The particle collector of any one of the preceding claims, wherein the drive chamber and the collection chamber are connected via a transition element.

12. Particle collector according to any one of the preceding claims, wherein the collection chamber comprises a collection chamber flow space connected to the drive chamber flow space, wherein preferably the drive chamber flow space and the collection chamber flow space are configured to allow the particles to flow in the collection chamber flow space to flow inside the drive chamber flow space at least partially in a substantially spiral and/or helical motion.

13. The particle collector of claim 12, wherein both the collection chamber and the drive chamber are substantially cylindrical in shape having substantially the same diameter, wherein the collection chamber is preferably aligned with the drive chamber.

14. Particle collector according to claim 12, wherein both the collection chamber and the drive chamber are substantially cylindrical in shape, wherein the diameter of the collection chamber is slightly larger than the diameter of the drive chamber, both the collection chamber and the drive chamber having substantially the same diameter, wherein the collection chamber is preferably aligned with the drive chamber.

15. The particle collector of any one of the preceding claims, wherein all of the one or more electrically conductive drive elements are connected to one voltage source.

16. The particle collector of any one of the preceding claims, wherein the collection chamber comprises a collection chamber wall defining a collection chamber flow space connected to the drive chamber flow space, wherein at least a portion of the collection chamber wall forms at least one second conductive member, wherein the second conductive member is grounded or connected to a second voltage source configured to apply a second voltage to the conductive member that is lower than the voltage applied to the one or more conductive drive elements.

17. The particle collector of claim 16, wherein the second voltage is a negative voltage.

18. The particle collector of any one of the preceding claims, wherein the inner surface of the collection chamber comprises one or more collection surfaces for collecting the particles thereon, wherein the collection surfaces have a substantially uniform charge distribution on an inner circumferential surface of the collection chamber.

19. The particle collector of claim 18, wherein the collection chamber wall comprises second conductive members and insulating members arranged alternately, the second conductive members and the insulating members alternating in an axial direction, wherein each of the members has a substantially uniform charge distribution on an inner circumferential surface of the collection chamber.

20. The particle collector of claim 19, wherein a second voltage applied to at least two conductive members in the collection chamber is different between the conductive members.

21. The particle collector of any one of the preceding claims, wherein the electrically conductive drive elements are mounted to the drive chamber wall and distributed at locations along an inner surface of the drive chamber wall to move particles in the contaminated gas in the generally spiral and/or helical motion.

22. The particle collector of claim 21, wherein the electrically conductive drive element is positioned along a helical trajectory in the flow space of the drive chamber.

23. The particle collector of claim 21 or 22, wherein the electrically conductive drive elements are positioned in a repeating pattern along an inner circumferential surface of the drive chamber wall.

24. The particle collector of any preceding claim, wherein each of the one or more electrically conductive drive elements is in the shape of a sharp point.

25. The particle collector of any preceding claim, wherein the electrically conductive drive element is oriented obliquely in a pattern relative to an inner surface of the drive chamber wall to move particles in the contaminated gas in the generally spiral and/or helical motion.

26. The particle collector of claim 25, wherein the obliquely oriented conductive drive element is arranged at an angle relative to the inner surface of the drive chamber wall, which angle can be broken down into two orthogonal angles, wherein a first angle (θ) is 0 ° -89 ° in the radial direction of the drive chamber relative to the normal of the surface of the drive chamber wall, wherein a second angle (θ) is

0-89 ° in an axial direction of the drive chamber relative to the normal to the surface of the drive chamber wall.

27. The particle collector of any preceding claim, wherein the collection unit is configured to collect moving particles arriving from the drive unit due to inertia of particles in a particle flow and/or electrical forces acting on the particles.

28. The particle collector of any preceding claim, wherein the electrically conductive drive element, the voltage source and electrically conductive member are configured to ionize particles by generating one or more ionizing coronas, and/or to generate an electric wind emanating from a tip of the electrically conductive drive element by accelerating the ionized particles from the electrically conductive drive element.

29. The particle collector of any preceding claim, wherein the drive chamber wall is made of a substantially insulating material.

30. Particle collector according to any of the preceding claims, further comprising a guiding unit for guiding particles towards the driving unit, wherein the guiding unit preferably comprises an electrically conductive surface, wherein the electrically conductive surface of the guide is connected to a voltage source, and wherein a higher positive voltage is applied to the electrically conductive surface of the guide, wherein the higher positive voltage is a higher voltage than the positive voltage applied to the electrically conductive driving element.

31. The particle collector of any preceding claim, wherein the particles removed from the contaminated gas comprise one or more of coal dust, fine dust, ultra-fine dust, water and chemical droplets, mist, bacteria, viruses, spores, pollen, soot, quartz, asbestos, metal particles, elemental carbon and/or exhaust gas particles and/or other particles having diameters on the order of nanometers.

32. The particle collector of any preceding claim, further comprising a controller unit for controlling one or more voltage supplies.

33. The particle collector of any preceding claim, further comprising a detector unit, wherein the detector unit comprises an ammeter, a particle detector, a presence detector and/or an environmental detector connected to the conductive drive element.

34. The particle collector of claims 32 and 33, wherein the control unit is connected to the detector unit and configured to control the voltage supply based on data from the detector unit.

35. A system comprising at least two particle collectors according to any of the preceding claims, wherein two or more particle collectors are arranged in series.

36. A method of removing particles from a gas, such as contaminated air, by operating a particle collector according to any of claims 1-34.

37. A method of removing particles from a gas according to claim 34, applied in cleaning contaminated air of indoor and/or outdoor environments, such as in and/or near areas in and/or near any of the following: a traffic system; demisting systems in traffic along roads, highways, traffic intersections, parking lots, parking spaces, automotive vehicles, schools, outdoor campuses, houses, factories, shipping vessels, transfer areas, wet and dry bulk material transfers, storage areas, ports, airports, airplanes, docks, offices, and/or the outdoor environment of these areas; and/or areas such as applied in and/or near: mining, construction site, laboratory, technical and/or medical clean room, hospital, nursery, intensive care unit, operating room, industrial factory area like a factory, and/or the method is applied as an air cleaning system for nano-sized particles and/or larger particles in a gas stream, and/or the method is combined with droplets as a gas scrubber.