WO1997039818A1

WO1997039818A1 - Ultra-filtration vacuum system

Info

Publication number: WO1997039818A1
Application number: PCT/US1997/006667
Authority: WO
Inventors: Michael John Edgington; Guy Merideth Hatch
Original assignee: Miracle Marketing Corporation; James, Randy, Bruce
Priority date: 1996-04-25
Filing date: 1997-04-23
Publication date: 1997-10-30

Abstract

A system for extracting small particulate dust from air is provided and uses a two-stage air handling system with a particulate entrapment fluid (125, 169) in the two stages, and a solid cartridge filter medium, the first stage (103) having a cyclone (115) for removing large debris, the second stage (105) having a dispersion chamber (171) nestled inside the top of the first stage (103), wherein air is injected directly into the liquid filter medium (169) through spiral vanes (159) contoured such that the surface of the swirling fluid (169) is made to tumble due to the cascading action. The third stage has a mechanical medium filtration system (107) provided to remove fine particulate matter.

Description

ULTRA-FILTRATION VACUUM SYSTEM

Field Of The Invention

This invention relates to ultra-filtration vacuum cleaner systems for separating fine particulates from the air.

Background of the Invention

For filtering particulates from air in a vacuum cleaning system, the basic goal is to remove particulate matter from the air passing through the system while maintaining an efficient air flow. Mechanical filters are frequently used, but can quickly become covered with and saturated with a cake of filtered material, reducing the efficient of the air flow through the filter.

Cyclone type vacuum cleaners are also known in the art, as disclosed, for

example, in United States Patent 2,233, 167 to Holm Hansen. This system functions as a centrifugal separator wherein incoming air is formed into a whiling annulus or cyclone. The solid particulates in the air, by virtue of their inertia tend to move to and impinge the outside wall where it settles into a collector or dust receptacle. In the Holm-Hansen system, water in the collector is driven by the whirling air into a wave the travels around the dust-receptacle, wetting and washing the wall. These systems work well to "rough clean" the air before extraction of the finest particles in the air by a mechanical filtration system. These systems work well, but unfortunately such a single-stage cyclone system as typically used in vacuum systems fails to remove enough

of the mid-range particulate to prevent premature caking of the final solid filter. Thus the final filter must be frequently replaced, and that filter is inefficiently used. The final filter is designed to remove the finest particles, but becomes quickly clogged and inoperative by large and mid-range particles. This is especially problematic when the

mechanical filter uses an ultrafine material, such as an expensive HEPA medium. 5 Another problem with cyclonic systems, like the Holm-Hansen system, that the particle removal, which depends upon the swirling of water by the air flow along the outer wall of the cyclone container, the removal efficiency often depends on the amount

of liquid and level of liquid in the system. Usually a relatively small amount of liquid is used to maintain the optimum action, but the liquid quickly becomes over-burdened i o with particulate material, reducing its effectiveness. In addition, when such a system is used as a "wet-vacuum," such as to remove water from a flooded carpet, the cyclone fluid chamber becomes over-filled with water and effective particulate entrapment stops.

It is, therefore, an object of the invention to provide a vacuum cleaning system

15 that avoids the problems of previous systems.

It is an object to provide a system that is more efficient than previous liquid medium filters in removing both coarse and fine particulate materials.

It is further an object to provide a vacuum filter system that be placed before

a mechanical filter to remove the bulk of mid-size and large particles to prevent a 20 premature clogging of the filter.

Further objects of the invention will become evident in the description below.

Summary Of The Invention The invention solves the problems of the prior-art by providing a new filtration system that uses a liquid filter medium to entrain particles from the air. Therefore,

unlike mechanical filters it does not quickly become clogged with filtered particulates. The filter of the invention is greatly more efficient than prior-art cyclone systems that also use liquid filter media, particularly in removing mid-size particles that are only poorly removed by a cyclone system.

The present invention is particularly suited for home and small-scale industrial/janitorial applications presently served by vacuum cleaners, although other applications are contemplated where removal of particles from air is required. In its

preferred embodiment, the present invention comprises an upright, barrel-shaped

console. Internally, the particulate extraction process is performed in three stages. First, the intake air, that has entrained solid particles of varying size distribution and any liquid water, is drawn first into pre-filter comprising a cyclone chamber where the

air flow is directed tangentially within a larger cylindrical-shaped chamber. As the air flow and particulate matter swirl about the inside of this vessel, the heavier particulate material and/or liquid moves, by centrifugal force, to the periphery, then falls, by gravity, to bottom of the chamber which is partially filled with a prepared chemical solution comprising water, low-sudsing surfactant, a disinfectant (also serving as an anti-static agent) and odor-modifying agents. The solution filled chamber also acts as

a holding vessel and has a high capacity to contain entrained liquids in the air.

The air, which is still suspending mid- and fine-range particulate material, exits

upwardly from the cyclone chamber via a centrally-located tube and conveyed from the first-stage by ducts to the second-stage. The second-stage comprises a dispersion chamber located circumferentially inside the first cyclone, to save internal space. It is also partially filled with a prepared chemical solution comprising water, low-sudsing surfactant, a disinfectant (also serving as an anti-static agent) and odor-modifying agents. In the dispersion chamber, the air flow is directed to the lower periphery of the fluid chamber, where it is released directly into the liquid. The channel through which the air is conveyed imparts a directional momentum to the air that is tangent to the outer wall of the chamber. Upon release directly into the liquid filter medium, the air stream transfers this momentum to the water such that a vigorous mixing action between the air and the filter medium is induced. The vigorous mixing action is induced by the rapid injection into the filter medium, resulting in rapidly rising air bubbles, and the circular, swirling action of the water induced by the tangential injection of the air. The swirling liquid medium flows up the periphery of the round- walled chamber. As the kinetic energy of the moving water is expended by the work of lifting the water, as well as by friction against the wall of the vessel, the water falls back to the bottom of the chamber. The net result is an irregularly-shaped wall of water resulting from the lifting, and cascading action of the water. Particulate material in the air impact this wall of water as the air bubbles and swirls upward within the more central portion of the dispersion chamber. Simultaneously, the rising air bubbles create a dispersion of liquid and air, with liquid continuously being thrown against and ricochetted off of the sides of the dispersion chamber. It has been found that this highly dispersed liquid in the air thus created, and the cyclonic effect against the water- wall materially increases the collection efficiency for small and medium-sized particles as compared to a solid static wall used in prior-art cyclone systems. This is even the case where the prior-art wall is wetted and washed by air induced waves as in the Holm-Hansen cyclone system. The present system, the swirling and cascading action of the water, and violently mixing liquid and air, and the rapid injection of air directly into the liquid medium increases the surface area of the liquid, which improves the

probability of impact and entrainment by the liquid.

The collection efficiency of the filter is further increased by chemical additives dissolved in the water which reduces the static electrical charge of the air and the surface tension of the water, both of which enhance the adhesion of the particles to the water surface. Air from the second stage filter stage then flows upward and out past two do- nut-shaped openings (plenums) in the top of the chamber designed to collect liquid in the water and prevent the liquid from flowing into the motor fan chamber. The air then

flows directly to the vacuum fan unit and is exhausted to atmosphere or, to achieve the

maximum extraction of particulates, the air preferably flows through a cartridge type filter before going to the vacuum fan and exiting.

A particular advantage of the present system over previous systems is that it can function as a wet vacuum or a dry vacuum without any modification. If, for example, a fine particulate material, such as large amounts of plaster dust or paint pigment, is passed into a conventional cyclone system contaimng a liquid filter medium, damp dust not collected by the filter quickly collects and clogs the mechanical filters that are

usually after the cyclone filtration. If a dry vacuum apparatus is used and there is incidentally any liquid entrained in the air stream, the powder likewise, quickly cakes

and clogs the filters. In any case, cyclone filters, either wet or dry, leave a significant

- 5 -

SUBST1TUTE SHEET (RULE 26) portion of dust, in the air leaving the filter that the mechanical filter is soon overloaded. The present vacuum apparatus characterized by a unique dispersion filter section removes a larger portion of particulate material than is removed with cyclone filters. The filtration functions whether liquid is or is not entrained in the incoming air stream. Particularly with the preferred embodiment, where a cyclone prefilter is used in conjunction with the dispersion filter system of the invention, essentially all of the

medium to large particles are removed, leaving a remnant comprising mostly the finest particles in the air stream. The use of splash plate baffles at the exit of the filter,

protects the mechanical filters by removing entrained liquid in the air stream. Thus, the mechanical filters are not damaged by liquids, or prematurely clogged by medium to large particles. Basically, the present system functions for a wide range of particulate solids, ranging from very fine pigments and dusts, to coarser materials. The invention is completely satisfactory for certain difficult environments, such as for large amounts of plaster dust, that can only with difficulty and frequent changing of mechanical filters be handled by previous systems. In addition, the superior function of the invention is essentially independent of presence or lack of water or other liquids

in the solid particulate materials or the air stream.

Brief Description Of The Drawings

Figure 1 is an exploded view of an apparatus of the invention.

Figure 2 is a perspective exploded view of the first filter section of the apparatus

of Figure 1. Figure 3 is a cross-section of the apparatus of Figure 1 along the center vertical

axis.

Figure 4 is a perspective view of the first and second filter sections with cutaway of the apparatus of Figure 1. 5 Figure 5 is an exploded view of the second filter section of the apparatus of

Figure 1.

Figure 6 is an exploded view of the mechanical filter section of the apparatus of Figure 1.

Figure 7 is an exploded view of the motor section of the apparatus of Figure 1. l o Figure 8 is an exploded view of the top cover of the apparatus of Figure 1.

Detailed Description Of The Invention

Figure 1 is an exploded perspective view of a vacuum apparatus of the invention 101. The apparatus comprises a first filter section 103, a second filter section 105, a third filter section comprising a mechanical filter section 107, a fan section 109, and

15 a top cover 111.

Referring to Figure 2, which is an exploded view of the first filter section 103 and Figure 3, which a vertical cross-section of the apparatus 101 of the invention, and Figure 4, which is a perspective view with a cut-away, air is drawn through air intake 113 into cyclone chamber 115, which is a generally barrel shaped chamber with a

20 bottom wall 117 and a generally vertical cylindrical side wall 119. The air is directed by a baffle 121 on the air intake to travel tangentially around the chamber. The middle to larger sized particles and/or liquid droplets entrained in the air are driven to the circumference of the cyclone chamber by centrifugal force, where they impact the inner surface 123 of the cylindrical side wall 119 and are collected by falling to bottom of

the chamber 115. Preferably the baffle 121 is directed slightly downward (about 20°). A filter medium 125 in the bottom collects the falling particles. The tangentially moving air also causes wave action that intermittently washes and wets the inner surface of the side wall. The cyclone section 103 is supported in an upright vertical position by suitable casters 127. At the air intake 113 is provided a hose attachment sleeve 133, for a bayonet attachment to a vacuum hose or the like, and a mounting plate 131 for securing the baffle 121 and the attachment sleeve 133 to the vertical wall using suitable fasteners, such as rivets or the like.

From the cyclone chamber, the air enters the second filter section filter 105. Referring to Figures 3 and 4, and also Figure 5, which is an exploded view of the second filter section 105, the second filter section 105 comprises a bottom tray 135

shaped generally like a Bundt pan with an annular shaped bottom 137, a cylindrical outer wall 139 extending upwardly from the outer edge of the bottom 137, and a cylindrical inner wall 141 extending upwardly from the inner edge of the bottom. An inverted cup-like cover 143, with a circular top 145 and downward extending cover wall 147, is disposed over the top edge 149 of the inner cylindrical wall to create an air flow path up from the first filter section through a second section inlet 151 at the junction of the annular bottom 137 and the inner cylindrical wall 141 , through the

inside annular space of the inner cylindrical wall 141 , between the top 145 of the

inverted cover 143 and the top 149 of the inner cylindrical wall 141 , down between the inner cylindrical wall 141 and the cover wall 147, and under the bottom edge 155 of the cover wall. At the bottom of the cover wall 155 is a generally horizontal and outward extending lip 157. Attached to the lip 157 are downwardly extending fins 159 or vanes. The function of the vanes 159 is to support the inverted cover 143 on the bottom of the annular bottom 137, and to direct the air flow as will be more

particularly described below.

On the lower surface of the annular bottom 137 is attached a cage 161 and a

float ball 163 that function as an over-fill safety valve. The vacuum apparatus of the invention can function as a wet-dry vacuum, filtering both liquids and solid particles from an incoming air stream. The bulk of the liquid in the incoming air stream will be retained by the first filter section 103 and be entrained with the filter medium 125 in the cyclone chamber 115. As the fluid level rises from accumulated fluid, a point would be reached without a safety valve when the mixture of filter medium and retained

fluid would become entrained in the air stream flowing into the second filter section up through its inner cylindrical wall, which would materially compromise the function of

the system, and allow fluid to be expelled from the vacuum. To prevent this from happening the float ball 163 is provided so that before the fluid can reach this level the

float ball approaches the inlet of the second filter section and becomes entrained in the air stream, forcing it to seat over and seal the inlet 151 of the second section 105, as shown in phantom. The ball 163 is then held in place by the vacuum above the ball, which disables the system and prevents any air, and thereby any liquid, in the first filter section from entering the inlet.

Placed over the inverted cover 143 are a lower splash plate 165 and an upper splash plate 167. The annular bottom 137, the inner and outer cylindrical walls 139, 141 , and the lower slash plate 165 filter dispersion chamber 171. A liquid filter medium 169 is placed within the bottom tray 135 to immerse the lip 157 of the inverted cover 143. During operation of the apparatus, air from the first filter section 103 enters second filter section inlet 151, flows through the annulus of the inner cylindrical wall 141 , over the top edge of the inner cylindrical wall 149, down between inner cylindrical wall 141 and the inverted cover 143, and under the lip 157 through the vanes 159 and out directly into the filter medium 169. Directing the air directly into the filter medium (rather than into the space above the medium) creates very efficient filtering environment in the dispersion chamber 171. The air injected forcefully into and through the filter medium forms bubbles that they travel upward and outward through the filter chamber, creating a liquid/air dispersion with a high liquid surface area. Solid particles in the air are thereby efficiently contacted with and entrained by the liquid filter medium. The air is injected into the medium at sufficient velocity to impart momentum to the filter medium. Dispersed liquid is propelled toward ricochets from the cylindrical walls 139, 141 and the cover plate which further disperses the air and the liquid. The effect is a violently mixing undulating two phase mixture of small air bubbles in fluid at the bottom and highly dispersed small fluid drops in air near the lower splash plate 167. The mixing may be also enhanced by ridges 148 or other extensions at the outlet of the air. Preferably the vanes 159 are angled to direct the incoming air in a tangential direction. This further enhances the dispersion of the liquid and air phase by lengthening the path of the air through the medium before the air reaches the outer wall. The incoming air imparts a circular momentum to the filter medium, which then begins to spin in the bottom tray, which directs the liquid outwardly upon the outer

cylindrical wall, creating an undulating wall of liquid. In addition, the spinning fluid

and air creates an effect that directs air particles and liquid toward the outer walls. The transition 164 between the outer cylindrical wall and the annular bottom is rounded to assist in the formation of the undulating liquid wall. This effect, together with the undulating wall of liquid and the dispersion effect of the air rising through the medium

effectively creates a liquid system that much more effectively contacts and retains solid particles than a simple cyclone where air is directed over the surface of the medium and particles are directed to a solid periodically wetted outer wall. The second filter section is particularly efficient at removing a larger portion

of the finer particles in the air stream than is the case for a cyclone system. The apparatus herein described can be described as a highly efficient liquid-medium filter in the second filter section 105 with a cyclonic prefilter in the first section 103. Essentially, the only particles in the air leaving the second section 105 are very small or ultra-fine particles.

As described above, dispersed liquid is propelled in the dispersion by the energy of the air injection. At the top of the dispersion chamber, dispersed liquid drops impact the underside of the annular lower splash plate 167. The liquid drops with entrained solid particles bounce off, or run down and drip off of the lower splash plate 167, and

become further involved in dispersion. A lower annular passage 173 is provided

between the inverted cover 143 and the inner edge 175 of the lower splash plate 167.

Air passes through this passage 173, and is directed outwardly between the lower splash plate 167 and the overlying upper splash plate 165, and then is redirected through an upper annular passage 174 between the outed edge of the upper splash plate and the out cylindrical wall of the bottom tray. Liquid medium still retained in the air impacts and adheres to the underside of the upper splash plate 165, the upper side of

the lower splash plate 167, and adjacent surfaces and is collected by and runs down the upper surface of the lower splash plate 167. The outer edge of the first splash plate is loosely fitted between the outer cylindrical wall allowing liquid flowing down the top of the first plate to flow over the outer edge of the first splash plate into the dispersion chamber. A cover plate 177 extends between the top edge 179 of the outer cylindrical wall 139. The cover plate includes a central aperture 181 for exit of the particle depleted air from the second filter section.

The second filter section 105 is placed circumferentially withing the first filter section 103 to save space and provide an efficient means of cleaning and maintenance of the vacuum apparatus. The bottom tray 135 of the second filter section comprises

an outer annular lip 183 that fits over the top edge 185 of the extended side wall 1 19 of the cyclone chamber 115 of the first filter section 103. The cover plate 177 for the second filter section fits over outer lip 183, and the assembly is joined and secured with releasable tension fasteners 129. A rubber seal 187 is provided at the edge of the outer lip 183 to seal the joinder against air and liquids.

To clean and maintain the vacuum apparatus the fasteners 129 are released and the cover plate 177, the upper splash plate 165 and the lower flash plate 167 are removed in succession. At this point the removed components can be easily cleaned

and access to the dispersion chamber 171 is provided. Filter medium may then be

added to the second filter section, or the dirty fluid in the second section removed by removing drain plug 189 by means of handle 191 , allowing the fluid to drain into the first filter section 103. The bottom tray 135 may then be removed allowing it and the attached cage 161 and float ball 163 to be cleaned, and allowing access to the cyclone chamber 115. Liquid in the cyclone chamber 115 comprising filter medium, entrained solid particles and liquids can then easily be supplemented by new fluid, or dumped. The cyclone chamber can then be easily cleaned if necessary and new fluid poured into

the cyclone chamber.

The filter medium for the first and second filter sections may the same or different, and is a filtering liquid designed to entrain particles. For the first filter section, the filter medium may be any medium conventionally used for cyclone vacuum system, such as water, preferably containing surfactants or the like. Preferably, for operational simplicity, the medium for the first filter section is the same as that of the second filter section.

For the filter medium 169 of the second filter section any suitable medium is contemplated, however, for optimum performance, a specialized solution is preferred. Most filter media suitable for cyclonic vacuums systems and the first filter stage will not optimally perform in the second filter stages. For optimal performance the second stage filter medium should have surfactant, antistatic, and antifoaming properties. The surfactant assists in dispersion of the filter medium, entrainment of the particles by the filter medium and adhesion of liquid filter medium drops to the surfaces in the dispersion chamber. The antistatic composition reduces generated static electrical charges that may cause particles and filter medium drops to repel each another. An antifoaming composition is required to prevent the foaming of material entrained by the medium and the surfactant that may otherwise occur from the violent mixing and dispersion in the dispersion chamber. The filter medium may also contain a biocide to prevent bacterial growth and the like in the medium, and a scent to cover unpleasant odors. Agents that assist in agglomerating or precipitating materials entrained in the filter medium may also be required. For example, for sheet rock dust, which is essentially CaSO₄, a calcium chelating agent may be used to precipitate the calcium and prevent from solubilizing in the medium. The filter medium is preferably nonhazardous and non-toxic and is preferably water based, but other solvent bases are

contemplated, as well as mixtures of solvents, for example, water and alcohols, or glycols. Basically, a goal of an optimum filter medium for the second section it to

reduce the natural repelling force between water (and other solvents) and solid particulates in the air. These forces derive from surface tension, static charges, surface incompatibilities between the solid and the solvent, and the like. In addition, foaming should be inhibited because of the violent mixing of the liquid and air phases in the

second section. It is within the skill of a practitioner of ordinary skill to select suitable

components and their proportions for the filter medium.

An example of suitable filter medium is first made as a concentrate and later

diluted with water. The concentrate comprises propylene glycol, a calcium chelating agents (Hampene NTA 150), a silicone defoaming agent, a surfactant (a 9 mol nonionnic surfactant, and a quaternary amine bactericide. The concentrate is then diluted with water at a suitable ratio, approximately 1 to 10 parts, but typically 5 parts

water to 1 part concentrate. The propylene glycol promotes wetting by reducing the surface tension of water and also reduces evaporation of the water. The defoaming

agent inhibits foaming and assists in wetting a precipitating the particles.

Referring to Figures 1 and 2, and Figures 6 to 8, which are exploded views of the mechanical section 107, the fan section 109, and the top cover 111 , respectively, of the third filter section. The air leaving the second section enters a third filter section 106 comprising the fan section 109, and mechanical filter section 107. The fan section

comprises a cylindrical fan impeller 193 of convention design for creating a vacuum, which is the driving force for drawing air though the first and second filter sections. Air is drawn from the second filter section 105 through the center aperture 181 and through the fan impeller 193. The fan impeller 193 is driven conventionally directly

by a high capacity drive motor 195. The motor is air cooled from an air stream independent from the filtered air stream. The cooling air is drawn through top apertures 197 to the motor and directed out through a side vent 199.

From the fan impeller 193 the filtered air is forced through apertures into the

mechanical filter section comprising mechanical filters for removing ultra-fine particles. Depending on the application, the filters may, for example, be for small particles in the micron range (about 1 to 10 microns) or be submicron filters, such as those of the HEPA design. The present invention efficiently utilizes this filter medium as essentially all of the larger particles have already been removed in the first and second

filter sections, leaving essentially only a remnant of ultra-fine particles. Thus, the

filters are not prematurely filled and clogged by filtration of the large particles. Thus, these filters last longer and are used primarily for their best function, which is to remove ultrafine particles. The mechanical filter section 107 comprises an inner annular ring of filter material 201 , and an outer annular filter ring 203, which is secured in place by gaskets 204. An outer ring 234 of a diffuser medium acts as both a filter and a motor noise suppressor.

The fan section 109 comprises a shell 207 that is shaped similar to an inverted

Bundt pan with holes 209 for mounting by screws to the cover plate 177 on the second filter section (also in Figure 3) also acts as a bottom mounting plate for the fan and mechanical filters. A gasket 211 seals around the central aperture 181. The shell 207 comprises an inverted U-shaped channel 213 for enclosing the filters and air inlet

apertures 215 for air passage between the fan impeller 193 and the mechanical filter section, and outlet apertures 217 to allow the filtered air to exit the mechanical filter section. The motor 195 with fan impeller 193 is attached to the shell 207 by means of screw fasteners and mounting plate 219, using appropriate gaskets 221 to secure the motor and seal the filtered air passages from the motor cooling air passages.

The top cover 111 comprises a cover shell 223 with the cooling air inlet and exit apertures 197, 199. The top cover protects the motor and defines the air passages for the air cooling motor. The inlet aperture 197 is provided with simple frequency dampeners 229 and cover screen 231. The exit aperture 227 is also provided with a screen 233. The top cover is mounted to the shell 207 by appropriate screw fasteners. Noise suppression materials 235 are provided, as appropriate in the top cover and the fan sections to suppress fan and motor noise.

The components of the vacuum apparatus of the invention may be manufactured

of any suitable material with suitable strength and corrosion resistance to the materials

being drawn and entrained in the apparatus, such as but not limited to metal and plastic materials. A preferred material is a high-strength corrosion resistant plastic, such a polyethylene or polypropylene, formed by conventional molding techniques. The size of the apparatus is chosen for its intended use, considering capacity, portability, etc. An apparatus essentially as described above in the Figures (which are essentially scale) was built that was 23 inches high and 18 inched in diameter.

While this invention has been described with reference to certain specific embodiments and examples, it will be recognized by those skilled in the art that many

variations are possible without departing from the scope and spirit of this invention, and that the invention, as described by the claims, is intended to cover all changes and modifications of the invention which do not depart from the spirit of the invention.

Claims

CLAIMS What is claimed is:

1. An filter apparatus for removing small particulates from an air stream comprising a dispersion chamber with means for directing a particle laden air stream

5 directly into a liquid to transfer momentum of the air directly to the liquid, the dispersion chamber constructed with surfaces against which liquid is propelled by the energy of the injected air to disperse the liquid in the air and the dispersion chamber shaped such that a cascading and undulating liquid surface is formed.

2. The filter apparatus of Claim 1 wherein the air is directed into the liquid io through vanes that direct the air and transfer momentum to the water in a tangential direction.

3. The filter apparatus of Claim 1 wherein the dispersion chamber comprises a circular bottom and cylindrical side wall with a rounded transition between the circular bottom and side wall.

l b 4. The filter apparatus of Claim 1 wherein the surfaces against which liquid is propelled are provided by one or more splash plates.

5. The filter apparatus of Claim 4 wherein the splash plate provide surfaces that collect liquid upon which the liquid flows to be further dispersed in the dispersion chamber.

6. The filter apparatus of Claim 1 additionally comprising a cyclonic prefilter wherein air is directed in a vortex over a second liquid medium in a circular cyclone chamber before it is injected into the dispersion chamber.

7. The filter apparatus of Claim 5 additionally comprising an additional mechanical filter wherein the splash plates remove essentially all liquid from the particle depleted air before it enters the mechanical filter.

8. An uitrafiltration vacuum apparatus comprising; a dispersion chamber with an air inlet and an air outlet, a means for forcing air into the air inlet through the dispersion chamber and out of the air outlet, the dispersion chamber constructed and configured to contain a liquid filter medium with the air inlet constructed and configure in direct air directly into the filter medium to create liquid/air dispersion and transfer momentum from the air stream directly to the liquid medium.

9. The uitrafiltration vacuum apparatus in Claim 8 wherein the dispersion chamber is generally cylindrical about a vertical axis with generally vertical side walls and the air inlet is constructed and configured to inject air into the liquid medium in a tangential direction to create a action that forces liquid medium to flow upon the vertical side walls and form a cascading liquid surface.

10. The uitrafiltration vacuum apparatus in Claim 9 wherein the cylindrical dispersion chamber has a rounded bottom to assist the rise upon the vertical walls of liquid medium by the centrifugal action.

11. The uitrafiltration vacuum apparatus in Claim 8 comprising further surfaces against which liquid entrained in the dispersion is propelled by energy from the injected air to further disperse the liquid in the air.

12. The uitrafiltration vacuum apparatus in Claim 8 comprising further surfaces are in the form of one or more splash plates which entrain liquid upon its surfaces and return the liquid to the dispersion chamber.

13. An uitrafiltration vacuum apparatus comprising;

(a) a first stage cyclone filter comprising means to direct particle laden air in a cyclone chamber in a vortex to direct particulates in the air to an outer wall of the cyclone chamber,

(b) a second stage filter comprising a means for directing air from the first stage filter, a dispersion chamber with means to direct air from the first stage filter directly into a liquid filter medium in the second stage filter to create liquid/air dispersion with increased liquid surface area and to transfer momentum from the air stream directly to the liquid medium, and surfaces for collecting liquid in the dispersion to be redispersed in the dispersion chamber and provide an exiting particle depleted air stream essentially free of liquid. (c) a third stage mechanical filter with means to direct liquid-free, particle depleted air stream from the second stage and pass it through the third stage filter.

14. The uitrafiltration vacuum apparatus of Claim 13 wherein the dispersion chamber is generally cylindrical about a vertical axis with generally vertical side walls and the air inlet is constructed and configured to inject air into the liquid medium in a tangential direction to create an action that forces liquid medium to flow upon the vertical side walls and form a cascading liquid surface.

15. A method for filtering particles from particle laden air comprising directing a particle laden air stream directly into a liquid filter medium within a dispersion chamber to form a dispersion of liquid in the air by energy of the air to propel and ricochet dispersed liquid off of walls of the dispersion chamber, the dispersion to contact and entrain solid particles in the air into the liquid, and separating the dispersed liquid containing entrained solid particles from the air stream and withdrawing the air to produce a filtered particle depleted air stream.

16. The method of filtering particles form particle laden air of claim 15 wherein the air is introduced into the dispersion chamber in a tangential direction to induce a swirling action of the liquid such that the liquid rises up side walls of the dispersion chamber to form an undulating wall of water.

17. The method of filtering particles from particle laden air of claim 15 wherein the liquid is a filter medium that functions to decrease repulsion forces between the liquid and the solid particles and to inhibit foaming.

18. The method of filtering particles from particle laden air of claim 17 wherein the filter medium contains a antifoaming agent and a surfactant.

19. The method of filtering particles from particle laden air of claim 17 wherein the filter medium comprises propylene glycol, a defoaming agent, a surfactant.

20. The method of filtering particles from particle laden air of claim 19 wherein the filter medium additionally comprises a quaternary amine bactericide, and a calcium chelating agent.