WO2006107754A2

WO2006107754A2 - Water filtration and recycling for stone fabrication equipment including exterior and architectural stone with enhanced volume capability

Info

Publication number: WO2006107754A2
Application number: PCT/US2006/011954
Authority: WO
Inventors: Ross Perry; Paula Perry
Original assignee: Stone Industry Recycling, Inc.
Priority date: 2005-04-04
Filing date: 2006-03-31
Publication date: 2006-10-12
Also published as: AU2006232189B2; US20050167371A1; WO2006107754A3; US20070062867A1; US20080190868A1; US7244366B2; EP1874429A2; AU2006232189A1; US7611624B2; US7713427B2; EP1874429A4

Abstract

A water treatment and recycling system for filtering grey waste water to clear water for stone fabrication equipment includes a waste water storage tank connected to receive grey water from stone fabrication equipment and a clear water supply loop. The clear water supply loop includes a high capacity filter assembly receiving waste water from the waste water storage tank and filtering the waste water into clear water that is provided to the fabrication equipment through a clear water storage tank. The high capacity filter assembly includes at least one high pressure filter unit wherein each high pressure filter unit includes a duplex air diaphragm pump assembly, forfiltering the waste water into the clear water.

Description

[00I]WATER FILTRATION AND RECYCLING FOR STONE FABRICATION

EQUIPMENT INCLUDING EXTERIOR AND ARCHITECTURAL STONE

WITH ENHANCED VOLUME CAPABILITY

[0021FIELD OF THE INVENTION

[003] The present invention is directed to a method and system for water treatment and, in particular, to a method and system for filtering particulate matter from a waste water slurry to provide reusable particulate free "crystal clear" water and, if desired, filtered gray water for processes having differing requirements and, in particular, for stone cutting and polishing processes and including the elimination of any waste water discharge to an on siteseptic facility or a privately owned treatment works (POTW) or a city sewer.

f0041BACKGROUND OF THE INVENTION

[005] Water is employed in a wide range of industrial processes and for a wide range of purposes, each of which imposes its own requirements or characteristics on the properties of the water entering and discharged by the process. Such requirements on the properties or characteristics of water used in or discharges from various processes in turn often result in water treatment processes necessary to make the water suitable or acceptable for use in or discharge from the process, and the various water treatment processes in themselves may be a major technical or economic component of an industrial process.

[006] Various industrial processes can impose a number of chemical and physical requirements on incoming water, such as acidity, salinity, temperature and so on, and corresponding requirements on discharge water, typically to meet environmental or health requirements. In many commonly found industrial processes, however, the principle requirements for input and discharge water concern the particulate or suspended contents of the water rather than, for example, the dissolved contents of the water. [007] Examples of processes in which the physical or mechanical contents of the intake and discharge water are the primary concern are found in the stone fabrication industry, such as those involved in cutting, shaping and polishing natural, engineered and man-made stone for such products as countertops, flooring, architectural paneling, and so on. As is well known by those of ordinary skill in these arts, water is commonly used to wash away the particulate waste material from the cutting and polishing processes, as a coolant to carry off heat produced by the processes, and often as a lubricant. As a consequence, stone cutting and polishing processes, whether of natural stone, engineered stone or man-made stone-like materials, generate heat and significant volumes of particulate waste material, both of which are carried away in and by the process discharge water. The discharge water is consequently referred to as "grey" water, because of the particulate waste material in the water. The particulate waste material is primarily comprised of the material being cut or polished, but will often include other particulate material, such as particles from the cutting and polishing tools themselves polishing or cutting compounds used with the tools and processes, and various other materials that find their way onto the floor and into the waste water system.

[008] The type and degree of treatment performed on the grey discharge water from the processes depends, in turn, on what is done with the discharge water. For example, the grey water that is eventually discharged from the processes and the treatment of the grey water before final discharge may be dictated by environmental or health factors. In some instances, the grey water may be treated in no more than a "settling tank" to allow at least some of the particulate waste to "settle out" as sediment before the water is returned, for example, to a river or discharged to enter the groundwater. In addition, water discharged into rivers, streams, groundwater and so on is required to meet state and federal requirements, which typically require ongoing random testing of the discharged water in compliance with the Clean Water Act. In most instances, environmental or health concerns may require removal of the particulate waste to the level of "crystal clear" water, as discussed below, as well as other MCL (maximum containment level) measurements before it is returned to the environment or original source.

[009] In still other instances, at least some of the grey water may be recycled to the processes as intake water, thereby reducing the total water volume requirements of the processes. The treatment of recycled grey water will depend, however, upon the uses to which the grey water is to be put. For example, certain processes, and in particular stone cutting, drilling and cooling processes, may use grey water containing a moderate amount of particulate waste as the particulate waste from a previous cycle through a stone cutting or polishing and Computer Numeric Controlled (CNC) process may not adversely effect a cutting, drilling, cooling or coarse grinding process. In such instances, the recycled grey water may require no more than a settling tank to allow sedimentation of enough of the particulate waste material that the remaining waste material does not "clog" the ensuing process in which it is used, or may require no treatment at all.

[010] In other instances, however, the process or processes receiving recycled water require "crystal clear" water, that is, water in which the volume and size of particulate matter is strictly limited. Stone polishing and CNC processes, for example, must use intake water that is "clear", that is, water that generally contains no particulate matter, except particles that are generally less than 1 or 2 microns in diameter, as larger particulate matter will interfere with the polishing or CNC process by making and leaving scratches that will prevent the desired degree of polish or finish, that may leave visible scratches and that may clog the polishing tools and CNC spindle.

[011] The recycling of grey water into "clear" water, however, is a technically and economically more complex and expensive process than a sedimentation tank as used to recycle grey discharged water to grey intake water for such processes as cutting, drilling, cooling and coarse grinding, and the choice is subject to many factors. For example, it may be less expensive to provide fresh intake water for those processes requiring "clear" water, and to treat all discharge water as grey water for both discharge and recycling purposes. In the alternative, however, and very often, the required quantities of fresh intake water, or intake water of sufficient quality, may not be available or may be more costly than cleaning and recycling grey water into crystal clear water, or the volume of grey water that may be discharged may be limited for any of a number of reasons.

[012] The problem, therefore, is to provide an environmental water discharge system for industrial processes such as stone cutting, grinding, cooling, polishing and for CNC equipments that virtually eliminates the required volume of fresh intake water and absolutely eliminates all grey discharge water from a facility, by economic and efficient recycling of grey water into crystal clear water and grey water in the required quantities.

[013] It will be seen from the following descriptions of the present invention that the general methods for removing particulate matter from grey water to provide clear water or a combination of clear water and filtered grey water for various purposes is not a straightforward process but contains many inherent problems that must be addressed in addressing the basic problem.

[014] For example, the general methods for the removal of particulate matter such as stone residue from a fluid such as water typically include settlement, which may also be referred to as sedimentation, and filtering. Sedimentation essentially employs the differences in density between the fluid and the particulate matter to separate one from the other and, which is usually relatively inexpensive, is relatively slow and is less effective as the particle size decreases. Also, while the sedimentation rate and particle separation capacities of a sedimentation system may be enhanced by, for example, centrifugal or chemical methods, these enhanced methods are much more expensive and typically provide questionable recycled water quality and volumes.

[015] Filtering methods pass the water and particulate matter through some form of trap or clarifier or other media that will capture the particles but will pass the water and typically are faster but much more expensive than simple sedimentation methods. For example, the "high pressure filter", or filter press, was originally designed to "dewater" solids that had settled in a collection tank or basin, that is, the particulate matter collected in a sedimentation tank in an industrial wastewater treatment environment. In the process, waste water bearing the waste particulate matter from an industrial process was allowed to stand in a sedimentation collecting tank to allow at least a part of the particulate matter to settle out of the water, often with the use of a chemical precipitant. The water, which may still contain a significant quantity of finer grained particulate matter (often called a 'pin-floc"), was then typically returned to the sedimentation tank to remove still more waste matter from the waste water. The particulate sediment settled out in the sedimentation tank, which contained a significant proportion of water, and was pumped to the filter press, which essentially removed the water from the sediment by trapping the sediment in the filer press and allowing the recovered water, also referred to as effluent, to return to the treatment system. The particulate waste collected in the filters of the filter press was then mechanically removed from the filters of the filter press and was typically discarded.

[016] A filter press of the prior art is therefore effective for removing water from sedimented particulate matter. When employed to remove particulate matter from water, however, which is an object of the present invention and discussed in the following descriptions of the present invention, filter presses have certain disadvantageous limitations. These limitations become particularly obvious when relatively higher volumes of filtered water per unit are required, such as filtered water flow rates up to 150 gallons per minute (gpm) per 20 cubic foot pressure.

[017] Stated briefly, the fluid dynamics within a filter press, when combined with the progressive accumulation of solids during the filtering process, prevents a typical 20 cubic foot filter press with an industry standard air actuated, double diaphragm air pump, from producing filtered water at a consistent, reliable, predictable flow rate when the flow rate demanded of the filter press reaches up to 150 gpm.

[018] It has been found, for example, that for a number of reasons standard, industry available filter press components and air diaphragm pumps will not permit the desired yield to be maintained at flow rates of 75 gpm and greater for filter presses having internal filter element volumes higher than a 20 cubic foot filter capacity with filter plates that measure approximately 800 - 1 ,000 mm in diameter. For example, in water filtration and recycling systems for stone fabrication shops the type and quantity of particulate solids that are generated during stone processing can result in "slumping" of the accumulated particulate solids in the filter plate voids if the accumulated weight or vertical loading of the particulate solids in the filer elements exceeds a given limit. Once slumping occurs, the filter cloths begin to foul, that is, become clogged with particulate matter as the "precoat" has been mostly removed and the cloth medic exposed. The flow rate of the filter press will thereby decrease unacceptably and much sooner than the capacity of the filter press would indicate the total solids capacity of the filter press will therefore not be achieved. The point at which slumping becomes a significant problem depends on the volume capacity of the filter press and the diameter of the filter plates, and it has been found that the practical upper limit on filter press filter capacity is approximately 20 cubic feet and the practical upper limit on filter plate size is in the range of 800-1 ,000 mm.

[019] It must also be noted that this problem cannot be alleviated or delayed by reducing the size, that is, the diameter, of the filter plates, because the length of the filter press, that is, the number of plates in the filter plate stack, must therefore be increased to maintain the desired flow rate through the filter press. The increase in the number of filter plates in turn increases the length of the flow path through the filter press and the weight, that is, the size and density, of the particles is typically such that the particles may not be carried through to the last several filter plates at normal flow rates. The particles will therefore tend to accumulate in the first several filter plates, which will then become full faster than would occur with larger plates, and the last several filter plates will tend to accumulate little waste. The clogging of the first several filter plates may cause the flow rate of the filter press to decrease much sooner than would be indicated by the filter volume of the press, and the total solids capacity of the filter press will not be achieved.

[020] It will be recognized, therefore, that these limitations on the capacity and flow rate of filter presses are a significant problem in larger stone processing shops wherein the required clean water flow volumes may reach, for example, up to 150 gpm. [021] It must also be recognized that while a filter press will typically be periodically cleaned at scheduled intervals, that is, the filter plates emptied of solids, it is necessary for the system to maintain at least a desired minimum filtered water flow rate over the entire period between filter press cleanings. The minimum desired flow rate, however, will typically be the flow rate normally required by the stone processing equipment in normal operation and may again reach up to 150 gpm per 20 cubic foot press. The flow rate capacity of the filter press will decrease over time, however, because of the accumulation of solids in the filter plates. As a consequence, the actual flow rate that must be achievable at all times may be significantly greater than the desired minimum flow rate.

[022] The present invention addresses and provides a solution for these and other related problems of the prior art.

IO231SUMMARY OF THE INVENTION

[024] The present invention is directed to a system and method for water treatment and recycling system for providing clear water, filtered grey water or grey water to a stone processing system.

[025] The water treatment and recycling system for providing clear water to clear water stone fabrication equipment includes a waste water storage tank connected to receive and store grey water from discharge ports of the clear water and grey water stone fabrication equipment and a clear water supply loop. The clear water supply loop, in turn, includes a high capacity filter assembly having an input port connected from the waste water storage tank to receive waste water from the waste water storage tank and to convert the waste water into the clear water, a clear water storage tank connected from a discharge port of the high capacity filter assembly to receive and store clear water from the high capacity filter assembly, and a clear water supply pump connected from the clear water storage tank for providing clear water from the clear water storage tank to the clear water stone fabrication equipment.

[026] According to the present invention, the high capacity filter assembly includes at least one high pressure filter unit wherein each high pressure filter unit or filter press includes duplex air diaphragm pumps (in parallel) having input ports connected to pump the waste water from the waste water storage tank to a high pressure filter for filtering the waste water into the clear water, and having an output port from the filter press connected to provide the clear water to the clear water storage tank.

[027] In a presently preferred embodiment, each high pressure filter has a capacity of no greater than 20 cubic feet at an average flow rate of approximately 7.5 gpm for each cubic foot of filter capacity and includes filter plates no larger than 800 mm - 1 ,000 mm diameter and each duplex air diaphragm pump assembly has a designed pressure capacity, for example, of 90 psi of pump backpressure at up to 100 gpm, and 80 psi of pump backpressure at up to 150 gpm.

[028] According to the present invention, the water treatment and recycling system may further include a grey water supply loop for providing grey water to grey water stone fabrication equipment. The grey water supply will include the waste water storage tank connected to receive and store grey water from discharge ports of the grey water and clear water stone fabrication equipment and a grey water pump connected from the waste water storage tank for pumping waste water from the waste water storage tank as grey water to an input port of the grey water stone fabrication equipment.

[029] Further according to the present invention, the water treatment and recycling system may also include a filtered grey water supply loop for providing filtered grey water to filtered grey water stone fabricating equipment. According to the present invention, the filtered grey water supply loop will include a grey water pump connected from the waste water storage tank for pumping waste water from the waste water storage tank as grey water and a filtered grey water filter path connected from a grey water output of the grey water pump and having a separation filter for removing large particulate waste from the grey water wherein the separation filter has a filtered grey water output connected to an input port of a particle filter for filtering smaller particulate matter, and discharging the large particulate waste through a second output into the waste water storage tank. [030] According to the present invention, each high pressure filter of a high capacity filter assembly includes a frame holding a filter stack including a head plate, a plurality of filter plates, a tail plate and a ram for applying axial pressure along the filter stack to force the head plate, the filter plates and the tail plate into a pressure tight assembly. The head plate and each of the filter plates include an axial input bore connecting sequentially along the filter stage to form an axial input passage for receiving waste water from the waste water storage tank and a plurality of discharge bores located circumferentially around the axial input passage to form a corresponding plurality of discharge passages extending along the length of the filter stack, the discharge passages being connected to one another outside of the head plate and to the clear water storage tank.

[031] Each of the filter plates further includes at least one filter chamber for containing and supporting active filter elements wherein each filter chamber is connected between the axial input passage and each of the plurality of discharge passages and the active filter elements removing particulate matter from the waste water flowing along the input passage to provide the crystal clear water discharged through the discharge passages. Lastly, the tail plate is located at the opposite end of the filter stack from the head plate and terminating the input passage and the discharge passages.

[032] The active filter elements will include a filter media extending across a filter chamber in a flow path between the input passage and the discharge passages communicating with the filter chamber with a granular filter layer coated upon and supported by the filter media for removal of particulate matter from the waste water, the granular filter layer being located in the flow path from the input passage to the discharge passages on the input passage side of the filter media. Each filter plate may also include a filter chamber gasket circumferentially surrounding at least one filter chamber to seal the at least one filter chamber to a next sequential one of a filter plate, the head plate and the tail plate and a discharge bore gasket circumferentially surrounding each discharge bore on one face of the filter plate to seal each discharge bore to a next sequential one of a filter plate, the head plate and the tail plate. [033] The present invention further includes a method for cleaning the filter stack of accumulated waste particulate matter. The cleaning method includes forcing air into the filter stack through a discharge passage to force air to flow through the filter chambers and the active filter elements to and through the input passage to force water from particulate waste matter captured by the active filter elements. The axial pressure on the filter stack is then released to permit separation of the head plate, the filter plates and the tail plate and the particulate waste matter captured by the active filter elements and a granular filter layer containing the captured particulate waste matter is then scraped from the surface of a filter media. The remaining captured particulate waste matter may be flushed from the surface of the filter media by means of a high pressure water hose system, the head plate, the filter plates and the tail plate are reassembled into a filter stack, and the axial pressure on the head plate, the filter plates and the tail plate is restored to force the filter stack into a pressure tight assembly. Clear water is then flushed through the filter stack in the normal direction of flow to flush residual waste matter from the filter stack, and the granular filter layer coating is restored to each filter media.

[034] A granular filter layer is applied to or restored onto each filter media by pumping a mixture of crystal clear water and a granular material comprising the granular filter layer into the input passage of the filter stack to flow through each filter media of each filter plate and through the discharge passages from the filter stack and recirculating the clear water returned from the discharge passages of the filter stack and replenishing the granular material mixed into the crystal clear water until a desired thickness of the granular material is deposited on the each filter media of each filter plate.

[0351BRIEF DESCRIPTION OF THE DRAWINGS

[036] The foregoing and other objects, features and advantages of the present invention will be apparent from the following description of the invention and embodiments thereof, as illustrated in the accompanying figures, wherein:

[037] Fig. 1 is a diagrammatic representation of a water processing system of the present invention in association with a stone processing system; [038] Fig. 2 is a diagrammatic representation of a high pressure filter of the present invention for filtering waste water into clear water; [039] Fig. 3A is a diagrammatic end view of a typical filter plate of the high pressure filter, which also illustrates an end plate and a head plate of the high pressure filter; [040] Fig. 3B is a cross section view of a filter stack of a high pressure filter, including a head plate, filter plates and a tail plate; [041] Fig. 3C is a cross section of the active filter elements of a high pressure filter for a filter plate having back-to-back filter chambers; [042] Fig. 4 is a diagrammatic representation of an alternate embodiment of a water processing system of the present invention for filtering waste water into recycled clear water and grey water, including exterior or architectural stone processing uses; [043] Fig. 5A is a diagrammatic representation of an alternate embodiment of a water processing system of the present invention as a high flow capacity system;

Fig.5B is a diagrammatic representation of a high capacity filter press and duplex pump assembly for use in a water processing system of the present invention as a high flow capacity system; [044] Fig. 6 is a diagrammatic illustration of a high capacity duplex air diaphragm pump assembly; and, [045] Fig. 7 is a diagrammatic representation of the characteristics of a high capacity duplex air diaphragm pump assembly.

[046IDETAILED DESCRIPTION OF THE INVENTION [047] A. Water Filtering and Recycling System

[048] Referring to Fig. 1 , therein is shown a diagrammatic representation of a

Water Treatment And Recycling System 10 of the present invention in association with a Stone Processing System 12 that includes Stone Processing Tools 14, which will typically include Stone Processing Tools 14A, such as bridge and gantry saws, routers, coarse grinders and cooling functions (including those of CNC Equipment), that may utilize "grey water" and Stone Processing Tools 14B, such as hand polishers, surface polishers, edge profilers, edge polishers, water jets and CNC Equipment that may require "Crystal Clear Water".

[049] In this regard, and for purposes of the present discussions and invention,

"grey water" may be defined as water containing particulate matter that is typically greater than 2 microns in diameter, and that is often significantly larger than 2 microns in diameter, while "crystal clear water" may be defined as water that typically includes only particulate matter less than or equal to 1 or 2 microns in size.

[050] As shown in Fig. 1 , therefore, and according to the present invention, a

Water Treatment And Recycling System 10 includes a Grey Water Loop 16G and a Crystal Clear Water Loop 16C, each providing the quality of water required for a given stone processing tool. For this purpose, and as indicated, the Grey Water Intakes 18 of Stone Processing Tools 14A, which can function with grey water, are connected from Grey Water Supply Line 20 of Grey Water Loop 16G while the Crystal Clear Water Intakes 22 of Stone Processing Tools 14B, which require crystal clear water, are connected from Crystal Clear Water Supply Line 24 of Crystal Clear Water Loop16C.

[051] As may be seen from Fig. 1 , Grey Water Loop 16G and Crystal Clear

Water Loop 16C share a common waste water discharge path from Stone Processing Tools 14A wherein Waste Water 26 from Waste Water Discharges 28 of Stone Processing Tools 14A and 14B are collected by Waste Water Collection Line 30, which in turn discharges Waste Water 26 into Waste Water Collection Tank 32. Waste Water Collection Tank 32 may be, for example, a below grade collection pit or an above ground storage or conventional tank, and is a holding reservoir for Waste Water 30 that is to be recycled as grey or crystal clear water. Waste Water Collection Tank 32 may also be a sedimentation facility for the recycling of Waste Water 26 into grey water and crystal clear water, if necessary.

[052] First considering Grey Water Loop 16G, as shown Waste Water 26 is drawn from Waste Water Collection Tank 32 and is pumped onto Grey Water Supply Line 20 as Grey Water 34 by Grey Water Pump 36. In a present embodiment of Water Treatment And Recycling System 10 Grey Water Pump 36 is, for example, a self-priming, electrically powered centrifugal pump delivering Grey Water 34 at, for example, 40 psi and at the volume required by Stone Processing Tools 14A, which will depend upon the. specific Stone Processing System 12. As indicated, Grey Water 34 from Grey Water Pump 36 is delivered through Grey Water Supply Line 20 to Grey Water Intakes 18 of Stone Processing Tools 14A, as described above.

[053] As shown, Grey Water Pump 36 is controlled from a conventional Control

Panel 38 having the necessary and conventional associated control circuits for controlling the operation of Grey Water Pump 36 and the delivery of Grey Water 34 to Stone Processing Tools 14A. For example, the control circuits associated with Grey Water Pump 36 will include a conventional Waste Water Float Sensor/Switch 4OL to control the operation of Grey Water Pump 36 dependent upon the level of Waste Water 26 in Waste Water Collection Tank 32.

[054] In particular, Waste Water Float Sensor/Switch 4OL prevents Grey Water

Pump 36 from operating if the level of Waste Water 26 in Waste Water Collection Tank 32 falls below a preset limit. This grey water cutoff limit is typically determined by the height of the Grey Water Pump 36 intake in Waste Water Collection Tank 32 and is chosen to prevent damage to Grey Water Pump 36 if the level of Waste Water 26 should fall below the level of the Grey Water Pump 36 intake.

[055] Also, when Grey Water Loop 16G is turned on, that is, Grey Water Pump

36 is turned on and enabled by Waste Water Float Sensor/Switch 40, Grey Water Pump 36 will run continuously to maintain the desired pressure in Grey Water Supply Line 20. The continuous operation of Grey Water Pump 36 also insures a continuous flow and recirculation of Grey Water 34 through Waste Water Collection Tank 32 to thereby insure that Waste Water Tank 32 is free from collecting sediments. A manifold or valve may also be connected from the base of Waste Water Collection Tank 32 to allow Waste Water 26 and any sediments accumulated in the base of Waste Water Collection Tank 32 to be flushed from Waste Water Collection Tank 32. The flow of Grey Water 34 is then controlled for each Stone Processing Tool 14A individually by tool water supply control valves associated with the Grey Water Intakes 18 of the individual Stone Processing Tools 14A. Keeping Waste Water Collection Tank 32 free of accumulated sediment thereby also protects Grey Water Pump 36 from "dead heading" in the event that control valves providing Grey Water 34 to Stone Processing Tools 14A are closed.

[056] Crystal Clear Water Loop 16C, like Grey Water Loop 16G, starts at Waste

Water Collection Tank 32 where Waste Water 26 that is to be recycled into Crystal Clear Water 42 is drawn from Waste Water Collection Tank 32 by Air Diaphragm Pump 44 and is provided under pressure to High Pressure Filter 46. High Pressure Filter 46, which is described further below, removes from the Waste Water 26 all particulate matter that is 1or 2 microns or greater in size, thereby recycling Waste Water 26 into Crystal Clear Water 42, and delivers the Crystal Clear Water 42 into a Crystal Clear Water Storage Tank 48.

[057] In a present embodiment of a Water Treatment And Recycling System 10,

Air Diaphragm Pump 44 is driven by air supplied, for example, at a maximum volume, for example, of up to 140 scfm and at a maximum pressure of up to 100 psi. The compressed air must be clean, dry air and it will be recognized that the volume and pressure of the air is dependent upon the desired volume of crystal clear water and the resistance offered by High Pressure Filter 46. It will be understood by those of ordinary skill in the relevant arts that the requirements for Air Diaphragm Pump 44 and the air required to drive the pump will thereby be dependent upon the crystal clear water volume requirements of Stone Processing System 12 and that these requirements will vary depending, for example, on the current state and efficiency of High Pressure Filter 46, such as the degree to which the filters therein are clogged by filtered particulate matter. For example, and continuing with the example just described, High Pressure Filter 46 will present approximately 5 to 10 psi of backpressure when the filtering apparatus is clean and Air Diaphragm Pump 44 will consume approximately 5 scfm of compressed air. When the filter apparatus in High Pressure Filter 46 is effectively full of particulate matter, High Pressure Filter 46 will present, for example, approximately 80 psi of backpressure and Air Diaphragm Pump 44 will consume up to 140 scfm of compressed air. [058] In a present embodiment, Air Diaphragm Pump 44 is controlled from

Control Panel 38 and is enabled or disenabled by, for example, Waste Water Float Sensor/Switches 4OU in Waste Water Collection Tank 32, which detects when the level of Waste Water 34 is adequate to supply Crystal Clear Water Storage Tank 48 through Air Diaphragm Pump 44 and when the level of Waste Water 34 in Waste Water Collection Tank 32 has fallen too low, thereby protecting Air Diaphragm Pump 44. Another float sensor in Crystal Clear Water Storage Tank 48, as described below, operates to maintain the necessary flow of water through High Pressure Filter 46 and others the necessary levels in Crystal Clear Water Storage Tank 48.

[059] The Crystal Clear Water 42 contained in Crystal Clear Water Storage

Tank 48 is drawn from Crystal Clear Water Storage Tank 48 and delivered to Stone Processing Tools 14B through Crystal Clear Water Supply Line 24 by a Crystal Clear Water Supply Pump 50. As in the case of Grey Water Pump 36 and Grey Water Supply Line 20, Crystal Clear Water Supply Pump 50 runs continuously to maintain a desired pressure in Crystal Clear Water Supply Line 24 so long as Crystal Clear Water Supply Pump 50 is turned on from Control Panel 38 and is enabled by float sensors in Crystal Clear Water Storage Tank 48. The flow of Crystal Clear Water 42 to the individual Stone Processing Tools 14B is then controlled by a valve at the discharge of clear water pump 50 and individual crystal clear water control valves located at the Crystal Clear Water Intakes 22 of the individual Stone Processing Tools 14B.

[060] As indicated in Fig. 1 , Crystal Clear Water Storage Tank 48 and the control circuits for Crystal Clear Water Supply Pump 50 include a Bottom Float Sensor/Switch 52B, a Middle Float Sensor/Switch 52M and an Upper Float Sensor/Switch 52U, each of which senses and indicates a level or level range of the Crystal Clear Water 42 in Crystal Clear Water Storage Tank 48. For example, Bottom Float Sensor/Switch 52B is located towards the bottom of Crystal Clear Water Storage Tank 48 and functions as a safety switch to protect Crystal Clear Water Supply Pump 50 by insuring that Crystal Clear Water Supply Pump 50 is enabled only when the level of Crystal Clear Water 42 in Crystal Clear Water Storage Tank 48 is at or above the water discharge level from Storage Tank 48 flowing to Crystal Clear Water Supply Pump 50. Upper Float Sensor/Switch 52U, in turn, is located toward the top of Crystal Clear Water Storage Tank 48 and operates to prevent overfilling of Crystal Clear Water Storage Tank 48. Upper Float Sensor/Switch 52U indicates when the Crystal Clear Water Storage Tank 48 is full to maximum safe capacity and turns off Air Diaphragm Pump 44 when this state is reached so that no more Crystal Clear Water 42 is supplied to Crystal Clear Water Storage Tank 48 until the level of Crystal Clear Water 42 therein has decreased below the trip level of Upper Float Sensor/Switch 52U, typically by a flow of Crystal Clear Water 42 to Stone Processing Tools 14B. Finally, in a present embodiment of a Water Treatment And Recycling

System 10 the normal operating range of the level of Crystal Clear Water 42 in Crystal Clear Water Storage Tank 48 is between Upper Float Sensor/Switch 52U and Middle Float Sensor/Switch 52M, that is, in the mid-levels of Crystal Clear Water Storage Tank 48 between Upper Float Sensor/Switch 52U and Bottom Float Sensor/Switch 52B. A Middle Float Sensor/Switch 52M is located at this level to indicate when the level of Crystal Clear Water 42 in Crystal Clear Water Storage Tank 48 is about to leave the normal operating range, which in the present implementation is between Middle Float Sensor/Switch 52M and Upper Float Sensor/Switch 52U. If the level of Crystal Clear Water 42 should fall below the level of Middle Float Sensor/Switch 52M, Middle Float Sensor/Switch 52M will indicate this condition, thus indicating that the operating levels of Crystal Clear Water Storage Tank 48 are falling outside the normal operating range and should be checked and the system adjusted. Middle Float Sensor/Switch 52M thereby provides a visual warning system of a possible undesirable operating trend, that is, that Crystal Clear Water 42 is being used faster than it is being provided from High Pressure Filter 46. Middle Float Sensor/Switch 52M does so by generating a visual warning signal before the output of Crystal Clear Water 42 to Crystal Clear Water Supply Line 24 is cut off when the level of Crystal Clear Water 42 in Crystal Clear Water Storage Tank 48 drops to the point where Bottom Float Sensor/Switch 52B is triggered. [062] Lastly with regard to Crystal Clear Water Storage Tank 48, it is shown in

Fig. 1 that a present embodiment of Crystal Clear Water Loop 16C includes an alternative Sterilization Loop 54 connected from the Crystal Clear Water Output 56 of Crystal Clear Water Supply Pump 50 and through a Sterilizer 58 and back into Crystal Clear Water Storage Tank 48. In the present embodiment of Water Treatment And Recycling System 10, Sterilizer 58 is an ultraviolet disinfection (UV) light that operates to destroy any bacteria that may grow in and contaminate the Crystal Clear Water 42 residing in Crystal Clear Water Storage Tank 48. Because Crystal Clear Water Supply Pump 50 operates continuously to maintain the desired pressure in Crystal Clear Water Supply Line 24 so long as it is enabled by Float Sensor/Switch 52B, as described above, there will be a continuous flow of Crystal Clear Water 42 from Crystal Clear Water Storage Tank 48, through Sterilization Loop 54 and back into Crystal Clear Water Storage Tank 48, thereby continuously disinfecting the Crystal Clear Water 42 therein. Sterilization Loop 54, by running continuously, also provides an escape or relief path for Crystal Clear Water Supply Pump 50 should Crystal Clear Water Loop 16C become "dead headed", such as by the closing of all control valves supplying Stone Processing Tools 14B.

[063] Referring now to Fig. 2, therein is shown a diagrammatic representation of a High Pressure Filter 46. As illustrated therein, and in addition to Air Diaphragm Pump 44, High Pressure Filter 46 includes a Frame 58 holding a Filter Stack 60 comprised of a steel Frame 58 with plumbing mounted to it, a Manifold Plate 64M, a Head Plate 64, a plurality of Filter Plates 62, and a Tail Plate 62E mounted on Frame 58. A Filter Stack 60 includes a Waste Water Input Port 64G through which Waste Water 26 enters Filter Stack 60 and a plurality of Crystal Clear Water Discharge Ports 64C through which Crystal Clear Water 42 is discharged from Filter Stack 60. A Hydraulic Ram 66 mounted to the Frame 58 controllably exerts axial pressure on a Push Plate 68, which in turn exerts axial force on Tail Plate 62E, the Filter Plates 62 and the Head Plate 64 to force Head Plate 64, Filter Plates 62 and Tail Plate 62E into a water and pressure tight Filter Stack 60 against steel Manifold Plate 64M, to which the Waste Water 26 and Crystal Clear Water 42 connections are made. [064] As illustrated schematically in Fig. 2, and as described further below,

Manifold Plate 64M, Head Plate 64 and Filter Plates 62 are constructed to form a central Input Passage 70 axially interconnecting a plurality of Filter Chambers 72 and forming a Waste Water 26 flow path from Waste Water Input Port 64G into Filter Chambers 72. Manifold Plate 64M, Head Plate 64 and Filter Plates 62 are also constructed to form a plurality of axial Discharge Passages 74 that are circumferential to and connected from Filter Chambers 72 to form a Crystal Clear Water 42 flow path from Filter Chambers 72 to corresponding Crystal Clear Water Discharge Ports 64C. Although not shown in detail, it should be noted that as indicated in Fig. 2 Crystal Clear Water Discharge Ports 64C are connected together at the four corner points outside of Manifold Plate 64M to form a single line to Crystal Clear Water Storage Tank 48, and Input Passage 70 and Discharge Passages 74 (see Fig. 3A) terminate at Tail Plate 62E.

[065] Referring to Figs. 3A, 3B and 3C, Fig. 3A is a diagrammatic end view of a typical Filter Plate 62, which also illustrates a Head Plate 64 and a Tail Plate 62E, while Fig. 3B is a cross section view of a Filter Stack 60 including a Head Plate 64, Filter Plates 62 and a Tail Plate 62E. Fig. 3C, in turn, is a diagrammatic cross sectional view of Active Filter Elements 102, including a Filter Diaphragm or cloth 104 and a Granular Filter Aid Layer 106 for a Filter Plate 62 having back-to-back Filter Chambers 72.

[066] As illustrated in Fig. 3A, therein is shown one Face 76 of a typical Filter

Plate 62, which will also be used to illustrate a Head Plate 64 and a Tail Plate 62E. As shown in Fig. 3A, a Filter Plate 62, a Head Plate 64 and an Tail Plate 62E are each comprised of a Plate Body Filter Recess 80 and a Filter Plate 62 has a Filter Recess 80 formed in the central region of each Face 76 face of Plate Body 78. Head Plate 64 and Tail Plate 62E, however, have a Filter Recess 80 in only the Face 76 mating with an adjacent Filter Plate 62, that is, on the Face 76 facing into the Filter Stack 60.

[067] As will be described further below, each Filter Recess 80 forms a Filter

Chamber 72 supporting and containing Active Filter Elements 102, as will be described in detail in the following. When a Filter Plate 62 is mated with another Filter Plate 62, therefore, the facing Filter Recesses 80 form back-to-back Filter Chambers 72 having a common input flow path from Input Passage 70 and common output flow paths to Discharge Passages 74.. A Filter Plate 62 mated with a Head Plate 64 will have a single Filter Chamber 72, as will Tail Plate 62E as in most embodiments only the Filter Plates 62 will include a double sided Filter Recess 80.

[068] It is necessary to isolate Discharge Passages 74 and the Crystal Clear

Water 42 therein from Input Passage 70 and the Waste Water 26 therein and to thereby force Waste Water 26 to pass through the Active Filter Elements 102 to become Crystal Clear Water 42.

[069] For this reason, one Face 76 of each Filter Plate 62 will include a Recess

Gasket 8OG surrounding the Filter Recess 80 and Discharge Bore Gaskets 84G surrounding the sections of Discharge Passages 74 extending through the Filter Plate 62. Each Recess Gasket 8OG and each Discharge Bore Gasket 84G seats against a mating Face 76 of a neighbor Filter Plate 62 or of Tail Plate 62E when Filter Plates 62, Head Plate 64 and Tail Plate 62E are forced together into a water and pressure tight Filter Stack 60.

[070] Each Manifold Plate 64M and each Head Plate 64 will have a Recess

Gasket 8OG surrounding the single Filter Recess 80 and Discharge Bore Gaskets 84G surrounding the sections of Discharge Passages 74 extending through the Manifold Plate 64M or Head Plate 64 on the Faces 76 of these plates that face into the Filter Stack 60, that is, in the direction of Tail Plate 62E.

[071] Each Face 76 of each Filter Plate 62, Head Plate 64 and Tail Plate 62E having a Filter Recess 80 will also have a Gasket Groove 110 surrounding the Filter Recess 80 in that Face 76 for receiving and securing the Active Filter Elements 102 contained in each Filter Recess 80, as will be discussed further below.

[072] The section of Input Passage 70 formed in each Filter Plate 62, in Head

Plate 64, in Tail Plate 62E and in Manifold Plate 64B is formed by an Input Bore 82 located centrally in the Filter Recesses 80 of the plates and the Input Bore 82 of Manifold Plate 64M, Head Plate 64, each Filter Plate 62 and Tail Plate 62E is aligned with the Input Bores 82 of other Filter Plates 62 and of Head Plate 64, Manifold Plate 64M and Tail Plate 62E to form Input Passage 70. In this regard, it must be noted that the Input Bore 82 in Tail Plate 62E does not extend through the Tail Plate 62E as the Input Passage 70 terminates at the Tail Plate 62E.

[073] The sections of Discharge Passages 74 formed in Manifold Plate 64M,

Head Plate 64, each Filter Plate 62, and Tail Plate 62E a corresponding plurality of Discharge Bores 84 located circumferentially around the Filter Recess 80 or Filter Recesses 80, and thus concentrically around Input Passage 70. The Discharge Bores 84 in Manifold Plate 64M, Head Plate 64, each Filter Plate 62 and Tail Plate 62E are each aligned with the corresponding Discharge Bores 84 of Manifold Plate 64M, Head Plate 64, other Filter Plates, 62, and Tail Plate 62E to form the corresponding Discharge Passages 74. In the case of an Tail Plate 62E, however, the Discharge Bores 84 do not extend through the Plate Body 78 as the Discharge Passages 74 terminate at the Tail Plate 62E.

[074] As discussed in further detail below, the Active Filter Elements 102 of a

Filter Stack 60 extend across and are supported in each Filter Recess 80 of each Filter Chamber 72 so that Waste Water 26 entering through Input Passage 70 flows through the Active Filter Elements 102 to become Crystal Clear Water 42 in Discharge Passages 74. For this reason, each Filter Recess 80, that is, each Filter Chamber 72, in Head Plate 64, in each Filter Plate 62 and in Tail Plate 62E is connected to Discharge Bores 84 through a plurality of Filter Discharge Grooves 86 formed in a Recess Face 88 of each Filter Recess 80 and Filter Discharge Passages 90 connecting the Filter Discharge Passages 86 with Discharge Bores 84. Filter Discharge Passages 86 and Filter Discharge Passages 90 thereby complete the flow path through which Waste Water 26 flows to and into Filter Chambers 72 through Input Passage 70 and Crystal Clear Water 42 flows from Filter Chambers 72 to and through Discharge Passages 74.

[075] It must be noted with respect to Discharge Passages 74 and Filter

Discharge Passage 86 that in a presently preferred embodiment of a Filter Stack 60 the sequence of Filter Plates 62 is formed of a sequence of alternating Filter Plates 62A and 62B arranged in the sequence: 62A, 62B, 62A, 62B ..., and so on. In the presently preferred embodiment, Filter Plates 62A and Filter Plates 62B differ only in that in a Filter Plate 62A the Filter Discharge Passages 90 are connected to the upper and lower Discharge Passages 74 on one side of the Filter Plate 62 while in a Filter Plate 62B the Filter Discharge Passages 90 are connected to the upper and lower Discharge Passages 74 on the opposite side of the Filter Plate 62. As will be discussed further below, this arrangement of alternating connections between the Filter Recesses 80 and Discharge Passages 74 provides improved water flow characteristics and patterns through the Filter Stack 60 during normal filtering operation, during drying of the sludge that accumulates on Active Filter Elements 102, in back-flushing of the Filter Stack 60, and in coating Filter Media 104 coated with a Granular Filter Aid Layer 106, as discussed in further detail in a following discussion. It should be noted that in a plate having two Filter Recesses 80, such as a Filter Plate 62, the Filter Recesses 80 may share common Filter Discharge Passages 90.

[076] It will be recognized and understood by those of ordinary skill in the arts that Filter Discharge Grooves 86 and Filter Discharge Passages 90 may be implemented in a number of alternate ways. For example, the Filter Discharge Grooves 86 of a Filter Chamber 72 may be replaced by a pattern of openings formed in a port plate set into the Filter Recess 80 and supporting the Active Filter Elements 102, thereby forming a space behind the port plate in which the water flowing through the Active Filter Elements 102 is collected before passing to Discharge Passages 84 through Filter Discharge Passages 90.

[077] In another embodiment, and for example, a Filter Plate 62, Tail Plate 62E or Head Plate 64, or all three or any combination thereof, may be a box-like structure comprised of a frame generally forming the outside perimeter of the Filter Plate 62, Tail Plate 62E ro Head Plate 64 and two face plates. In this embodiment, Filter Discharge Grooves 86 would instead be formed by patterns holes in the face plates and the Input Bores 82 and Discharge Bores 84 would be formed by tubular members extending between the face plates, using blank face plates where necessary in between the Head Plate 64 and Tail Plate 62E.

[078] Next considering the Active Filter Elements 102 supported by and contained in the Filter Chambers 72, Fig. 3C is a diagrammatic cross sectional view of a Filter Stack 60, including a sequence of Filter Plates 62 forming a midsection portion of a Filter Stack 60, the input/output end section of the Filter Stack 60 including a Manifold Plate 64M, and the closed end section of the Filter Stack 60 including an Tail Plate 62E.

[079] As described herein above, Filter Plates 62 mate face-to-face with other

Filter Plates 62 or with a Head Plate 64 or an Tail Plate 62E so that their Input Bores 82 mate to form an Input Passage 70 and their Discharge Bores 84 mate to form Discharge Passages 74 with each Filter Recess 80 forming a Filter Chamber 72. As illustrated in Fig. 3C, each Filter Chamber 72 contains and supports Active Filter Elements 102 of a Filter Stack 60 wherein Active Filter Elements 102 rest upon Recess Face 78 and over Filter Discharge Grooves 86. As described, Active Filter Elements 102 are those elements of High Pressure Filter 46 that capture and filter out the particulate matter as necessary to convert Waste Water 26 into Crystal Clear Water 42 and, according to the present invention, Active Filter Elements 102 are coated with a Granular Filter Aid Layer 106.

[080] In the presently preferred embodiment, the Filter Media 104 for each Filter

Chamber 72 is attached to a Face 76 of Head Plate 64, Filter Plate 62 or Tail Plate 62E around the periphery of the Filter Recess 80 by means of a Rope Gasket 108 stitched into the outer circumference of the Filter Media 104 and "force fit" seated into a Gasket Groove 110 in the Face 76 and extending around the periphery of the Filter Recess 80. Filter Media 104 thereby extends across the Filter Recess 80 over Filter Grooves 86 and is attached and sealed to the Face 76 around the Filter Recess 80. As indicated in Fig. 3A, the outer perimeter of Filter Media 104, and thus Rope Gasket 108 and Gasket Groove 110, are octagonal. It will be recognized, however, that the outer perimeter of Filter Media 104 and thus Rope Gasket 108 and Gasket Groove 110 may be of any desired shape, such as circular. It will also be recognized that Rope Gasket 108 may be formed in a number of ways, such as by being woven into the perimeter of Filter Media 104 rather than as an initially separate component stitched into or onto the Filter Mambrane 104. Rope Gasket 108 may also be made of any material that has a mass adequate to secure the Filter Media 104 to the plate. [081] In the case of a Filter Plate 62 with two back-to-back Filter Chambers 72,

Filter Media 104 is comprised of two back-to-back Media Plates 112, each forming the section of Filter Media 104 extending across one of the two Filter Recesses 80. As shown, Each Media Plate 112 has a circular Input Bore Opening 114 corresponding to the Input Bore 82 of the Filter Plate 62, and the two Media Plates 112 are connected between the Input Bore Openings 114 by a cylindrical Media Plate Connector 116, so that the Filter Discharge Grooves 86, Filter Discharge Passages 90 and Discharge Bores 84 of each Filter Chamber 72 are completely separated from the Input Passage 70 by the Filter Media 104.

[082] In the case of an Tail Plate 62E or of a Head Plate 64 containing a Filter

Chamber 72, there is only one Filter Chamber 72 and the Filter Media 104 is thereby comprised of a single Media Plate 112. In the case of a Tail Plate 62E neither an Input Bore Opening 114 or Media Plate Connector 116 is required as the Input Passage 70 and Discharge Passages 84 terminate at the Tail Plate 62E. In the case of a Head Plate 64, an Input Bore Opening 114 is required. As indicated in Fig. 3D, a hole is cut into the single Media Plate 112 of filter cloth 104 and fitted over a Centering Nipple 64N where a lock nut secures the Media Plate 112 to the Head Plate 64.

[083] In the presently preferred embodiment of the present invention, Filter

Medias 104 are preferably comprised of a woven fabric material having an Oxford weave of multifilament yarn made of polypropylene fibers and having a specific weight of approximately 14oz. per square yard, a thread count of approximately 75x2 per square inch, and a sfm rating of approximately 2-3. The presently preferred filter cloth is manufactured, or stitched, by C.Goodman & Co., Inc. of Paterson, NJ as style number 42614, and is presently formed into Filter Medias 104 by C.Goodman & Co., Inc. Or its successor company. The Filter Medias 104 may typically have diameters in the range of 1 to 6 feet, with the diameters of Filter Medias 104 and the number of Filter Plates 62 in the Filter Stack 60 being dependent on the desired flow volume of Crystal Clear Water 42.

[084] Next referring to Granular Filter Aid Layers 106, the upstream side of each Filter Media 104, that is, the side of each Filter Media 104 towards Input Passage 70, is coated with a Granular Filter Aid Layer 106 comprised of a granular filter material capable of capturing the particulate waste matter present in Waste Water 26. Each Granular Filter Aid Layer 106 thereby performs two functions, one being to aid in the filtration of particulate matter from Waste Water 26, that is, to capture particulate waste matter to prevent the particulate waste matter from reaching the Filter Media 104 itself. The second function is to prevent the particulate waste matter from penetrating the surface of the Filter Media 104 and causing premature "fouling" of the Filter Media 104that is either captured by the Granular Filter Aid Layer 106 itself or that is stopped from passing through the Filter Media 104 by the Filter Media 104 itself.

[085] Each Granular Filter Aid Layer 106 is comprised of a layer of granular, porous material comprised of amorphous alumina silicate of the form commonly referred to by the trade name "Perlite", which is obtained from the heat treatment expansion of extracts from perlite ore, and having a thickness of approximately 0.1 lbs of Perlite per square foot of Filter Media 104 area. In the present embodiment of Granular Filter Aid Layers 106, the material comprising Granular Filter Aid Layers 106 is comprised of "Perlite" product number H 700 available from Harborlite Corp., which is located in Lompoc, California, and which is a perlite products division of World Minerals Inc., which is located in Santa Barbara, California.

[086] The material employed in Granular Filter Aid Layers 106 in the presently preferred embodiment of the present invention, that is, "Perlite" product number H 700 from Harborlite Corp., is referred to as Food Codex Grade whole filter aid powder and is comprised of the form of amorphous alimina silicate known by the tradename "Perlite". The material has a density of 11.0 pounds per cubic foot in the packaged form and a density of 13.2 pounds per cubic foot in the cake form, a median particle size of 35.6 microns, a median pore size of 18.1 microns, a specific gravity of 2.3 and a DARCY permeability of 1.24 and a 140 mesh screen retain factor of 8%. However, other grades may be necessary to effect proper filtration with varying types of stone particualte.

[087] In summary, therefore, Waste Water 26 enters a Filter Stack 60 through

Input Passage 70, which is comprised of the Input Bore 82 segments in Head Plate 64 and in each Filter Plate 62 and which connects Filter Chambers 72 such that Waste Water 26 can readily flow through Input Passage 70 from Input Bore 82 of Head Plate 64 into each Filter Chamber 72 along the Input Passage 70 and to the termination of Input Passage 70 at Tail Plate 62E. In each Filter Chamber 72, the Waste Water 26 flows through the Granular Filter Aid Layer 106 and the Filter Media 104 of Active Filter Elements 102, and, as Crystal Clear Water 42, flows through Filter Discharge Grooves 86 and Filter Discharge Passages 90 and into Discharge Bores 84. As described, each Discharge Bore 84 is a segment of a Discharge Passage 74 and Crystal Clear Water 42 thereby flows through Discharge Passages 74 to and through Head Plate 64, where the flow of Crystal Clear Water 42 from the Discharge Passages 74 are combined into a single flow to Crystal Clear Water Storage Tank 48.

[088] The filtering of Waste Water 26 into Crystal Clear Water 42 will result in the accumulation of particulate waste matter filtered from the Waste Water 26 in each filter chamber 72 mixed in part with the Granular Filter Aid Layers 106 and this combination of waste material compressed against each Filter Cloth 104. The buildup of "sludge" in each filter chamber 72 and on each Filter Media 104 will result in a gradually increasing backpressure in the Filter Stack 60 until the flow of Waste Water 26 into Filter Stack 60 and the flow rate of Crystal Clear Water 42 from Filter Stack 60 is reduced to a level below that which is desired. At this point it is necessary to clean the "sludge" from Filter Stack 60.

[089] A Filter Stack 60 is cleaned by first forcing air into the Filter Stack 60 through one of the upper Discharge Passages 74 in the reverse direction of the normal liquid flow, whereupon the air will flow into passages and chambers of the Filter Plates 62, Head Plaate 64 and Tail Plate 62E and will force water from the sludge deposit in filter chamber 72 and out the lower Discharge Passage 74 connected to the Filter Chamber 72, which is left open for this purpose. The forcing of water out of the sludge deposit in Filter Chamber 72 will transform the sludge from a watery mud into a dryer and more solid deposit that is more manageable than the original watery sludge, which would typically drop off the Filter Medias 104 as soon as the Filter Stack 60 is opened. The air is forced into one upper Discharge Passages 74 through an air connection fitting connecting to a selected Discharge Passage 74. In a presently preferred embodiment, however, the air fitting is connected to plumbing that is in turn connected into Manifold Plate 64M and through Manifold Plate 64M to one or more Discharge Passages 74 through an air fitting mounted on Manifold Plate 64M separate from Discharge Passages 74,

[090] The pressure exerted by Hydraulic Ram 66 on Push Plate 68 and thereby on Tail Plate 62E, Filter Plates 62, End Plate 64 and Manifold Plate 64M is then released so that Filter Plates 62 and Tail Plate 62E can be separated and removed by means of the Plate Handles 78H located on each side of each Plate Body 78. The Granular Filter Aid Layer 106, the granular material of which contains and is now a part of the sludge on each Filter Media 104, is then scraped off of each Filter Media 104 and the Filter Medias 104 are washed with a high pressure hose spray to remove the last of the sludge layer and any particulate waste matter caught in the fabric of the Filter Medias 104. This process is normally performed on Head Plate 64 "in place" as Head Plate 64 is typically permanently mounted onto Frame 58 adjacent to Manifold Plate 64M.

[091] The Filter Plates 62 and Tail Plate 62E are then reassembled into the

Filter Stack 60 and the pressure exerted by Hydraulic Ram 66 is restored to force the Tail Plate 62E and the Filter Plates 62 into contact with each other and with Head Plate 64 and Manifold Plate 64M to form the air and pressure tight Filter Stack 60. Crystal Clear Water 42 is then pumped from a Cleaning System Storage Tank 118 and through the Filter Stack 60 in the normal direction of flow from Input Passage 70 to Discharge Passages 74 until all residual particulate matter is washed from the Discharge Passages 74.

[092] It will be apparent that, at this stage, and while the Filter Stack 60 is cleaned, reassembled and flushed, there are no Granular Filter Layers 106 coating the Filter Medias 104, and that the Granular Filter Layers 106 must be applied onto the Filter Medias 104 before use of the Filter Stack 60.

[093] The application of Granular Filter Layers 106 onto the Filter Medias 104 is accomplished by connecting the Cleaning System Storage Tank 118 of crystal clear water to Input Passage 70 through Air Pump 44, with the Discharge Passages 74 being returned back to Cleaning System Storage Tank 118. The volume of crystal clear water in Cleaning System Storage Tank 118 is dependent upon the capacity of the Filter Stack 60 and should be sufficient to fill the Filter Stack 60, to fill the piping between the Cleaning System Storage Tank 118 and Filter Stack 60, including the capacity of Air Pump 44, and an additional margin in Cleaning System Storage Tank 118. It should also be noted that Cleaning System Storage Tank 118 may be, for example, a barrel, tank or "pit".

[094] The crystal clear water in Cleaning System Storage Tank 118 is then

"charged" with a quantity of the material comprising the Granular Filter Layers 106, which will be used to pre-coat the Filter Media 104, with the volume of pre- coat material being dependent on the square footage of Filter Media 104 contained in Filter Stack 60. The mixture of crystal clear water and pre-coat material is then pumped into Input Passage 70 and crystal clear water will flow out of Discharge Passages 74 and back to Cleaning System Storage Tank 118 while the pre-coat material is filtered out of the water by each Filter Media 104, thereby forming the Granular Filter Aid Layer 106 on each Filter Media 104. This process may be repeated as necessary with successive charges of the pre-coat material being added to the water until the necessary thickness of Granular Filter Aid Layer 106 is deposited on each Filter Media 104, which as described is on the order of 0.1 Ib of pre-coat material per each square foot of area of the Filter Media 104 in the Filter Stack 60. Water continues to "recirculate" through the Cleaning System Storage Tank 118until all pre-coat material has been removed by being deposited on Filter Media 104, and the Filter Stack 60 will then be ready for use.

[095] As described herein above, a typical implementation of a presently preferred embodiment of a High Pressure Filter will include one Tail Plate 62E, one Head Plate Plate 64 mounted rigidly to Frame 58, wherein Frame 58 includes Manifold Plate 64M mounted on Frame 58, several Filter Plates 62 which are mounted into Frame 58, and the Hydraulic Ram 66, which is attached between Frame 58 and Push Plate 68. Filter Plates 62 and Filter Medias 104 may be between 1 and 6 feet across and approximately 2 to 4 inches thick, while the single Input Passage 70 and Discharge Passages 74, of which there are typically 4, may range from 1 to 3 inches in diameter. [096] Next considering alternate embodiments and implementations of a Water

Treatment And Recycling System 10 of the present invention, the stone fabrication industry may be regarded as comprised of two distinct and often separate but related fields, one which may be referred to as "interiors" or "countertop" stone processing and the other of which may be referred to as "exterior" or "architectural" stone processing. "Interiors" stone processing, which is addressed above is typically comprised of the fabrication, for example, of countertops for residential or commercial use, and is typically characterized a lower volume of stone processing but to a high degree of finish on the stone.

[097] As described above with respect to a Water Treatment And Recycling

System 10, "interior" stone processing typically requires both a relatively high volume of relatively low quality water for stone cutting and rough finishing processes and a supply of very high quality recycled water, typically with allowable particle sizes of 1 or 2 microns or less after filtration, for high quality stone processing operations, such as final polishing. A Water Treatment And Recycling System 10 as described herein above is intended to meet these requirements for "interior" stone processing operations.

[098] "Exterior" or "architectural" stone processing, however, is typically characterized by a lower standard of finish on the stone but significantly higher volumes of stone being processed. "Architectural" stone processing may therefore require significantly higher volumes of water than "interior" stone processes, but typically does not require as high a quality of water as does "interior" stone processing because the desired or required standard of final finish is lower than is required in "interior" stone processing. For example, filtration to particle sizes of 75 microns and below is typically acceptable, although certain processes may require polishing to the "crystal clear" level, as described above, as well.

[099] Stated another way, the "grey" water produced by the above described

Water Treatment And Recycling System 10 is typically of acceptable quality for the rough cutting and rough shaping and finishing processes of "exterior" or "architectural" stone processing. The finer shaping and finish steps in "exterior" or "architectural" stone processing, however, require water of a quality that, while not as high as the clear water standard for "interior" stone processing, is higher than the grey water standard for interior stone processing and will be referred to hereinafter as "filtered grey water". It will also be understood that, as described herein above, certain processes or the "architectural" stone processing shop must meet the "crystal clear" standard, as well. The "filtered grey water" requirements, however, may be met by an appropriate adaptation of a Water Treatment And Recycling System 10.

[100] B. Water Filtration and Recycling System With Filtered Grey Water

[101] Referring now to Fig. 4, therein is illustrated a Water Treatment And

Recycling System 10G of the present invention wherein a Water Treatment And Recycling System 10 of the present invention is adapted for the specific requirements of filtering waste water from Stone Processing Tools 14 into recycled grey water for high volume exterior and architectural stone processing. As will be described in further detail in the following, a Water Treatment And Recycling System 10G is required to provide an adequate flow of Filtered Grey Water 34F to Stone Processing Tools 14A, wherein Filtered Grey Water 34F may be defined as water containing particulate matter of no greater than 75 microns, and to maintain an adequate reserve supply of Grey Water 34, including removing excess or oversized particulate matter.

[102] It must also be noted that it may be necessary or desirable for a Water

Treatment And Recycling System 10G to be capable of providing adequate flows of Clear Water 42 for "interior" and "exterior" stone processing, as described herein above with respect to a Water Treatment And Recycling System 10. In this instance, the system will be capable of operating as a water filtration system for either or both an "exterior" or "architecture" stone processing system and an "interior" stone processing system, either alternately or concurrently.

[103] As may be seen in Fig. 4, the resulting Water Treatment And Recycling

System 10G will include an Filtered Grey Water Loop 16GA that, in effect, parallels the Grey Water Supply Line 20 of a Water Treatment And Recycling System 10 as illustrated in Fig. 1 and that thereby shares part of Grey Water Loop 16G but includes a Filtered Grey Water Path 2OF. As shown, Filtered Grey Water Path 2OF is connected between the output of Grey Water Supply Pump 36 and Grey Water Intakes 18 of Stone Processing Tools 14A and typically includes a Separation Filter 120S. In a filtered grey water system of the present invention, Separation Filter 120S employs mechanical separation technology, such as a centrifugal style separator available from, for example, Lakos Systems and removes larger particles, that is, particles down to the 75 micron size, from Waste Water 26 drawn from Waste Water Collection Tank 32. As shown, Separation Filter 120S has a Large Particle Output 120L discharging water containing the separated larger particles to Waste Water Collection Tank 32 to be removed from the Waste Water 26 therein by other filtration processes, described below.

[104] The grey water output of Separation Filter 120S may be passed though a Particle Filter 120F for removal of remaining particles to whatever size is deemed necessary for Stone Processing Tools 14A, wherein Separation Filter 120F may be, for example, a filter available from Rosedale Products. It should be noted, however, that the filtration processes of Filtered Grey Water Path 2OF are complimented through other filter processes, such as through the recycling loop through High Pressure Filter 46 as described below. In these embodiments, the system would include a Recycling Path 122R from the outlet of Gray Water Supply Pump 36 and back to Waste Water Collection Tank 32, thereby providing a significant flow of Waste Water 26 from and back into Waste Water Collection Tank 32. This flow will thereby keep the solid waste particles in Waste Water 26 in Waste Water Collection Tank 32 in suspension for removal through the alternate filter path, such as the filter path through High Pressure Filter 46 as described below.

[105] As indicated generally in Fig. 4, Filtered Grey Water Path 20F may be connected into the system in place of Grey Water Supply Line 20, thereby comprising the only grey water flow path from Grey Water Supply Pump 36 to Stone Processing Tools 14A. This would be the typical configuration used, for example, in a Water Treatment System 10G that was intended for only "exterior" or "architectural" stone processing. Filtered Grey Water Path 2OF may be connected in parallel with Grey Water Supply Line 20 by means of, for example, Valves 122A and 122B, whereupon the water filtration system may selectively operate as either or both of Water Treatment System 1 OG and a Water Treatment System 10. In other embodiments, however, such as when the systems is required to also provide "crystal clear" water, the Clear Water Supply Loop 16C would also be provided, as described herein above.

[106] As described above, it is necessary or at least preferable that the Water

Treatment System 10G remove at least the larger particulate waste in the Waste Water 26 in Waste Water Collection Tank 32 to provide a suitable and adequate reserve of Grey Water 34 for Filtered Grey Water Path 20F and Stone Processing Tools 14A. It will be apparent that Separation Filter 120S alone is inadequate for this task as it returns the larger particulate waste to Waste Water Collection Tank 32, so that the Waste Water 26 in Waste Water Collection Tank 32 would simply accumulate larger and larger quantities of particulate waste.

[107] In a presently preferred embodiment of a Water Treatment System 10G, therefore, the filtration path through High Pressure Filter 46, which is described in detail herein above, is employed to recycle Waste Water 26 from Waste Water Collection Tank 32 through a Clear Water Return Path 124 that includes the path from Waste Water Collection Tank 32, through High Pressure Filter 46 and back to Waste Water Collection Tank 32. This path thereby continuously recycles and filters the Waste Water 26 in Waste Water Collection Tank 32 to reduce or at least maintain the level of particulate matter therein. As shown in Fig. 4, in this application the return path from High Pressure Filter 46 does not return to Clear Water Storage Tank 42, but instead bypasses Clear Water Storage Tank 42 and returns directly to Waste Water Collection Tank 32. As in the case of Filtered Grey Water Path 2OF, a Valve 122C may be employed at the branching of the clear water output path from High Pressure Filter 46, thereby allowing the clear water from High Pressure Filter 46 to be directed to either Clear Water Storage Tank 42 or Waste Water Collection Tank 32, depending upon system demands and whether the system is being operated as either or both of Water Treatment System 10G and a Water Treatment System 10.

[108] Lastly, a Water Treatment System 10G may further include a Clear Water

Overflow path 126 running from an overflow level of Clear Water Storage Tank 48 and to Waste Water Collection Tank 32 and controlled through a Valve 122D, thereby avoiding the overflow waste of clean water and allowing continuous operation of the system during the startup phases of operation.

[109] Finally, it should be noted that a Filtered Grey Water Path 2OF with either or both of a Separation Filter 120S and a Particle Filter 120F may be employed in a Water Treatment System 10 in place of the Grey Water Supply Line 20 to provide a higher level of filtration for the water provided to Stone Processing Tools 14A, if so desired.

[110] C. Water Filtering and Recycling System With Increased Capacity

[111] As discussed herein above, the present invention also addresses the limitations of filter presses in producing filtered water at a consistent, reliable, predictable flow rate when the filter presses have a capacity greater than an a certain upper limit, and stone fabrication equipment high demands for crystal clear water greater than a certain limit.

[112] As described, the fluid dynamics within a filter press, when combined with the progressive accumulation of solids during the filtering process, prevents a typical filter press with an industry standard air actuated, double diaphragm air pump, from producing filtered water at a consistent, reliable, predictable flow rate equate to 7.5 gallons per minute (gpm) per cubic foot capacity of the filter press.

[113] It has also been found that for a number of reasons standard industry available filter press components (including an industry standard air pump) will not permit the desired yield or flow rate to be maintained for filter presses having internal filer element volumes higher than 20 cubic feet filter capacity or filter plates larger than approximately 800 - 1 ,000 mm diameter. As described, these limitations are generally due to slumping of the solids or particulate in the filter plates and the uneven accumulation of solids between the first and last filter plates and normal fluid flow rates through the filter plates.

[114] It is therefore apparent that these limitations become a significant problem in larger stone processing shops wherein the required crystal clear water flow volumes may reach up to 150 gpm, which is the current upper limit range for filter presses having a filter capacity of about 20 cubic feet and a flow rate capacity of 7.5 gpm per cubic foot of filter press area. [115] According to the present invention, therefore, and a described in detail below, stone processing facility flow rates above 100 to 150 gpm are to be achieved using filter presses having a filter capacity of approximately 20 cubic feet and filter plates no larger than approximately 800 - 1 ,000 mm diameter. Under these conditions, the flow rate through the filter press is preferably maintained at an average flow rate of approximately 7.5 gpm for each cubic foot of filter capacity for the maximum possible time period to provide an average flow rate of up to 150 gpm from a 20 cubic foot filter press.

[116] First consider the present invention with respect to providing a recycling system capable of providing flow rates of 100 to 150 gpm or more, Figs. 5A and 5B are a diagrammatic illustration of a High Capacity Water Treatment And Recycling System 10H of the present invention. As will be discussed, a High Capacity Water Treatment And Recycling System 10H of the present invention is capable of providing filtered water flow rates in excess of up to 150 gpm and beyond.

[117] As may be seen from a comparison of Figs. 4 and 5A and 5B₁ the High

Capacity Water Treatment And Recycling System 10H shown in Figs.5Aand 5B is similar to the Water Treatment And Recycling System 10G of Fig. 4, but is adapted for higher crystal clear water flow rates. It will be apparent from the following description of a High Capacity Water Treatment And Recycling System 10H that a Water Treatment And Recycling System 10 as illustrated in Fig. 1 may be similarly adapted for higher filtered water flow rates.

[118] As has been described herein above, Water Treatment And Recycling

System 10G as shown in Fig. 4 and a High Capacity Water Treatment And Recycling System 10H as shown in Figs. 5A and 5B is similar to a Water Treatment And Recycling System 10 as adapted for the specific requirements of filtering waste water from Stone Processing Tools 14 into recycled grey water for high volume exterior and architectural stone processing. As described, a Water Treatment And Recycling System 10G and a High Capacity Water Treatment And Recycling System 10H are required to provide an adequate flow of Filtered Grey Water 34F to Stone Processing Tools 14A, wherein Filtered Grey Water 34F may be defined as water containing particulate matter of no greater than 75 microns, and to maintain an adequate reserve supply of Grey Water 34, including removing excess or oversized particulate matter.

[119] It must also be noted that a Water Treatment And Recycling System 10G or a High Capacity Water Treatment And Recycling System 10H will also be required to provide adequate flows of Clear Water 42 for "interior" stone processing, as described herein above with respect to a Water Treatment And Recycling System 10. In this instance, the High Capacity Water Treatment And Recycling System 10H will thereby be capable of operating as a water filtration system for either or both an "exterior" or "architecture" stone processing system and an "interior" stone processing system, either alternately or concurrently, and of providing Clear Water 42 at flow rates of or exceeding 100 to 150 gpm per 20 cubic foot press.

[120] The following will first discuss the structure and operation of a High

Capacity Water Treatment And Recycling System 10H as a Water Treatment And Recycling System 10 or 10G as illustrated in Figs. 1 and 4, but adapted as illustrated in Figs. 5A and 5B to comprise a High Capacity Water Treatment And Recycling System 10H providing enhanced Clear Water 42 flow rates of or in excess of 100 to 150 gpm per 20 cubic foot press. The following will then briefly discuss the grey water circuit adaptations of a water treatment and recycling system as illustrated with respect to the Water Treatment And Recycling System 10G as shown in Fig. 4 and the corresponding aspects of the High Capacity Water Treatment And Recycling System 10H shown in Figs. 5A and 5B.

[121] As discussed previously, a Stone Processing System 12 will include

Stone Processing Tools 14, which will typically include Stone Processing Tools 14A, such as bridge and gantry saws, routers, coarse grinders and cooling functions (including those of CNC Equipment), that may utilize "grey water" and Stone Processing Tools 14B, such as hand polishers, surface polishers, edge profilers, edge polishers, water jets and CNC Equipment that may require "clear water".

[122] In this regard, and for purposes of the present discussions and invention,

"grey water" may be defined as water containing particulate matter that is typically greater than 2 microns in diameter, and that is often significantly larger than 2 microns in diameter, while "clear water" may be defined as water that typically includes only particulate matter less than or equal to 1 or 2 microns in size.

[123] As shown in Figs. 1 and 5A and 5B, a Water Treatment And Recycling

System 10 and High Capacity Water Treatment And Recycling System 10H include a Grey Water Loop 16G and a Clear Water Loop 16C, each providing the quality of water required for a given stone processing tool 14. For this purpose, and as indicated, the Grey Water Intakes 18 of Stone Processing Tools 14A, which can function with grey water, are connected from Grey Water Supply Line 20 of Grey Water Loop 16G while the Clear Water Intakes 22 of Stone Processing Tools 14B, which require Clear Water, are connected from Clear Water Supply Line 24 of Clear Water Loop16C.

[124] As previously described, Grey Water Loop 16G and Clear Water Loop

16C share a common waste water discharge path from Stone Processing Tools 14A and 14B wherein Waste Water 26 from Waste Water Discharges 28 of Stone Processing Tools 14A and 14B are collected by Waste Water Collection Line 30, which in turn discharges Waste Water 26 into Waste Water Collection Tank 32. Waste Water Collection Tank 32 may be, for example, a below grade collection pit or an above ground storage or conventional tank, and is a holding reservoir for Waste Water 30 that is to be recycled as grey or Clear Water. Waste Water Collection Tank 32 may also be a sedimentation facility for the recycling of Waste Water 26 into grey water and Clear Water, if necessary.

[125] First considering Grey Water Loop 16G, as shown Waste Water 26 is drawn from Waste Water Collection Tank 32 and is pumped onto Grey Water Supply Line 20 as Grey Water 34 by Grey Water Pump 36. In a present embodiment of Water Treatment And Recycling System 10 Grey Water Pump 36 is, for example, a self-priming, electrically powered centrifugal pump delivering Grey Water 34 at, for example, 40 psi and at the volume required by Stone Processing Tools 14A, which will depend upon the specific Stone Processing System 12. As indicated, Grey Water 34 from Grey Water Pump 36 is delivered through Grey Water Supply Line 20 to Grey Water Intakes 18 of Stone Processing Tools 14A, as described above. [126] As previously described and as shown, Grey Water Pump 36 is controlled from a conventional Control Panel 38 having the necessary and conventional associated control circuits for controlling the operation of Grey Water Pump 36 and the delivery of Grey Water 34 to Stone Processing Tools 14A. For example, the control circuits associated with Grey Water Pump 36 will include a conventional Waste Water Float Sensor/Switch 4OL to control the operation of Grey Water Pump 36 dependent upon the level of Waste Water 26 in Waste Water Collection Tank 32.

[127] Clear Water Loop 16C, like Grey Water Loop 16G, starts at Waste Water

Collection Tank 32 where Waste Water 26 that is to be recycled into Clear Water 42 is drawn from Waste Water Collection Tank 32 by Air Diaphragm Pump 44 and is provided under pressure to High Pressure Filter 46. High Pressure Filter 46, which is described further below, removes from the Waste Water 26 all particulate matter that is 1 or 2 microns or greater in diameter, thereby recycling Waste Water 26 into Clear Water 42, and delivers the Clear Water 42 into a Clear Water Storage Tank 48.

[128] In a present embodiment of a Water Treatment And Recycling System 10,

Air Diaphragm Pump 44 is driven by air supplied, for example, at a maximum volume of up to 140 scfm and at a maximum pressure of up to 100 psi. The compressed air must be clean, dry air and it will be recognized that the volume and pressure of the air is dependent upon the desired volume of Clear Water and the resistance offered by High Pressure Filter 46. It will be understood by those of ordinary skill in the relevant arts that the requirements for Air Diaphragm Pump 44 and the air required to drive the pump will thereby be dependent upon the Clear Water volume requirements of Stone Processing System 12 and that these requirements will vary depending, for example, on the current state and efficiency of High Pressure Filter 46, such as the degree to which the filters therein are clogged by filtered particulate matter. For example, and continuing with the example just described, High Pressure Filter 46 will present approximately 5 to 10 psi of backpressure when the filtering apparatus is clean and Air Diaphragm Pump 44 will consume approximately 5 scfm of compressed air. When the filter apparatus in High Pressure Filter 46 is effectively full of particulate matter, High Pressure Filter 46 will present, for example, approximately 80 psi of backpressure and Air Diaphragm Pump 44 will consume up to 140 scfm of compressed air.

[129] In a present embodiment, Air Diaphragm Pump 44 is controlled from

Control Panel 38 and is enabled or disenabled by, for example, Waste Water Float Sensor/Switches 4OU in Waste Water Collection Tank 32.

[130] The Clear Water 42 contained in Clear Water Storage Tank 48 is drawn from Clear Water Storage Tank 48 and delivered to Stone Processing Tools 14B through Clear Water Supply Line 24 by a Clear Water Supply Pump 50. As in the case of Grey Water Pump 36 and Grey Water Supply Line 20, Clear Water Supply Pump 50 runs continuously to maintain a desired pressure in Clear Water Supply Line 24 so long as Clear Water Supply Pump 50 is turned on from Control Panel 38 and is enabled by float sensors in Clear Water Storage Tank 48. The flow of Clear Water 42 to the individual Stone Processing Tools 14B is then controlled by a valve at the discharge of clear water pump 50 and by individual Clear Water control valves located at the Clear Water Intakes 22 of the individual Stone Processing Tools 14B.

[131] As indicated in Fig. 1 , Clear Water Storage Tank 48 and the control circuits for Clear Water Supply Pump 50 include a Bottom Float Sensor/Switch 52B, a Middle Float Sensor/Switch 52M and an Upper Float Sensor/Switch 52U, each of which senses and indicates a level or level range of the Clear Water 42 in Clear Water Storage Tank 48 for control purposes, as previously described.

[132] With regard to the above, it must be noted that the functions of

Sensor/Switches 40U, 4OL, 52U, 52M, 52B in a Water Treatment And Recycling System 10 and in a High Capacity Water Treatment And Recycling System 10H may be performed instead by single float type switches sensing the upper, middle and lower level limits in Waste Water Collection Tank 32 and in Clear Water Storage Tank 48, respectively.

[133] Lastly with regard to Clear Water Storage Tank 48, it is shown in Figs. 1 and 5A and 5B that a present embodiment of Clear Water Loop 16C includes an alternative Sterilization Loop 54 connected from the Clear Water Output 56 of Clear Water Supply Pump 50 and through a Sterilizer 58 and back into Clear Water Storage Tank 48. In the present embodiment of Water Treatment And Recycling System 10, Sterilizer 58 is an ultraviolet disinfection (UV) light that operates to destroy any bacteria that may grow in and contaminate the Clear Water 42 residing in Clear Water Storage Tank 48. Because Clear Water Supply Pump 50 operates continuously to maintain the desired pressure in Clear Water Supply Line 24 so long as it is enabled by Float Sensor/Switch 52B, as described above, there will be a continuous flow of Clear Water 42 from Clear Water Storage Tank 48, through Sterilization Loop 54 and back into Clear Water Storage Tank 48, thereby continuously disinfecting the Clear Water 42 therein. Sterilization Loop 54, by running continuously, also provides an escape or relief path for Clear Water Supply Pump 50 should Clear Water Loop 16C become "dead headed", such as by the closing of all control valves supplying Stone Processing Tools 14B.

[134] Next considering the modifications to a Water Treatment And Recycling

System 10 to provide filtered grey water as shown in the Water Treatment And Recycling System 10G of Fig. 4 and the High Capacity Water Treatment And Recycling System 10H of Figs. 5A and 5B, the resulting Water Treatment And Recycling System 10G or High Capacity Water Treatment And Recycling System 10H will include an Filtered Grey Water Loop 16GA. The Filtered Grey Water Loop 16GA essentially parallels the Grey Water Supply Line 20 of a Water Treatment And Recycling System 10 as illustrated in Fig. 1 and that thereby shares part of Grey Water Loop 16G, but further includes a Filtered Grey Water Path 2OF.

[135] As shown, Filtered Grey Water Path 2OF is connected between the output of Grey Water Supply Pump 36 and Grey Water Intakes 18 of Stone Processing Tools 14A and typically includes a Separation Filter 120S. In a filtered grey water system of the present invention, Separation Filter 120S employs mechanical separation technology, such as a centrifugal style separator available from, for example, Lakos Systems and removes larger particles, that is, particles down to the 75 micron size, from Waste Water 26 drawn from Waste Water Collection Tank 32. As shown, Separation Filter 120S has a Large Particle Output 12OL discharging water containing the separated larger particles to Waste Water Collection Tank 32 to be removed from the Waste Water 26 therein by other filtration processes, described below.

[136] The grey water output of Separation Filter 120S may be passed though a Particle Filter 120F for removal of remaining particles to whatever size is deemed necessary for Stone Processing Tools 14A, wherein Separation Filter 120F may be, for example, a filter available from Rosedale Products. It should be noted, however, that the filtration processes of Filtered Grey Water Path 2OF may be implemented through other filter processes, such as through the recycling loop through High Pressure Filter 46 as described below. In these embodiments, the system would include a Recycling Path 122R from the outlet of Gray Water Supply Pump 36 and back to Waste Water Collection Tank 32, thereby providing a significant flow of Waste Water 26 from and back into Waste Water Collection Tank 32. This flow will thereby keep the solid waste particles in Waste Water 26 in Waste Water Collection Tank 32 in suspension for removal through the alternate filter path, such as the filter path through High Pressure Filter 46 as described below.

[137] As indicated generally in Fig. 4, Filtered Grey Water Path 2OF may be connected into the system in place of Grey Water Supply Line 20, thereby comprising the only grey water flow path from Grey Water Supply Pump 36 to Stone Processing Tools 14A. This would be the typical configuration used, for example, in a Water Treatment System 10G that was intended for only "exterior" or "architectural" stone processing. Filtered Grey Water Path 2OF may be connected in parallel with Grey Water Supply Line 20 by means of, for example, Valves 122A and 122B, whereupon the water filtration system may selectively operate as either or both of Water Treatment System 10G and a Water Treatment System 10. In other embodiments, however, such as when the systems is required to also provide "crystal clear" water, the Clear Water Supply Loop 16C would also be provided, as described herein above.

[138] As described above, it is necessary or at least preferable that the Water

Treatment System 10G remove at least the larger particulate waste in the Waste Water 26 in Waste Water Collection Tank 32 to provide a suitable and adequate reserve of Grey Water 34 for Filtered Grey Water Path 2OF and Stone Processing Tools 14A. It will be apparent that Separation Filter 120S alone is inadequate for this task as it returns the larger particulate waste to Waste Water Collection Tank 32, so that the Waste Water 26 in Waste Water Collection Tank 32 would simply accumulate larger and larger quantities of particulate waste.

[139] In a presently preferred embodiment of a Water Treatment System 10G, therefore, the filtration path through High Pressure Filter 46, which is described in detail herein above, is employed to recycle Waste Water 26 from Waste Water Collection Tank 32 through a Clear Water Return Path 124 that includes the path from Waste Water Collection Tank 32, through High Pressure Filter 46 and back to Waste Water Collection Tank 32. This path thereby continuously recycles and filters the Waste Water 26 in Waste Water Collection Tank 32 to reduce or at least maintain the level of particulate matter therein. As shown in Fig. 4, in this application the return path from High Pressure Filter 46 does not return to Clear Water Storage Tank 42, but instead bypasses Clear Water Storage Tank 42 and returns directly to Waste Water Collection Tank 32. As in the case of Filtered Grey Water Path 2OF, a Valve 122C may be employed at the branching of the clear water output path from High Pressure Filter 46, thereby allowing the clear water from High Pressure Filter 46 to be directed to either Clear Water Storage Tank 42 or Waste Water Collection Tank 32, depending upon system demands and whether the system is being operated as either or both of Water Treatment System 10G and a Water Treatment System 10.

[140] Lastly, a Water Treatment System 10G may further include a Clear Water

[141 ] Finally, it should be noted that a Filtered Grey Water Path 2OF with either or both of a Separation Filter 120S and a Particle Filter 120F may be employed in a Water Treatment System 10 in place of the Grey Water Supply Line 20 to provide a higher level of filtration for the water provided to Stone Processing Tools 14A, if so desired. [142] Next, Figs. 5A and 5B illustrate the modifications to a Water Treatment

And Recycling System 10 or 10G to construct a High Grey Water and Clear Water Capacity Water Treatment And Recycling System 10H, using a Water Treatment And Recycling System 10G as an exemplary basis for the modification. As may be seen from Figs. 5A and 5B, the modification of a Water Treatment And Recycling System 10 or 10G to construct a High Capacity Water Treatment And Recycling System 10H principally involves modifications to the air diaphragm Filter Pump 44 and High Pressure Filter 46 elements of the water treatment and recycling system, and the associated piping.

[143] As illustrated in Figs. 5A and 5B, a High Capacity Water Treatment And

Recycling System 10H achieves potential Clear Water 42 flow rates of 100 to 150 gpm or higher by employing a High Capacity Filter Assembly 46A comprised of one or more High Pressure Filter Units 46U, designated as High Pressure Filter Units 46UA - 46Un. Each High Pressure Filter Unit 46U is in turn comprised of a High Pressure Filter 46 of the general type described herein above with regard to Water Treatment And Recycling Systems 10 and 10G, and a Duplex Air Diaphragm Pump Assembly (Fig. 6) 44D that will be described in further detail in a following discussion. The High Pressure Filter Units 46UA - Un of the High Capacity Filter Assembly 46A are connected in parallel, so that the potential flow rate capacity of the parallel arrangement of High Pressure Filter Units 46UA - Un. That is, the potential flow rate capacity of High Capacity Filter Assembly 46A is approximately the sum of the potential flow rate capacities of the High Pressure Filters 46 (up to 150 gpm per 20 cubic foot press) of the High Pressure Filter Units 46UA - Un.

[144] As illustrated, the High Pressure Filter Units 46UA-Un of High Capacity

Filter Assembly 46A are connected in parallel, so that in each High Pressure Filter Unit 46U the input port of each High Pressure Filter 46 is connected from an output port of the corresponding Duplex Air Diaphragm Pump Assembly 44D and the input ports of the Duplex Air Diaphragm Pump Assembly 44D is connected from Waste Water Collection Tank 32 and for cleaning purposes as described herein above to cleaning system storage tank 118. The Duplex Air Diaphragm Pump Assembly 44D of each High Pressure Filter Unit 46U thereby draws Waste Water 26 from Waste Water Collection Tank 32 and provides the Waste Water 26 under pressure to the High Pressure Filter 46 of the High Pressure Filter Unit 46U, wherein the Waste Water26 is filtered into Clear Water 42.

[145] The output ports of High Pressure Filters 46 of the High Pressure Filter

Units 46UA - Un of High Capacity Filter Assembly 46A are connected in parallel to a line to Clear Water Storage Tank 48, so that Clear Water 42 is delivered to and stored in Clear Water Storage Tank 48 as previously described. As previously described, the Clear Water 42 contained in Crystal Clear Water Storage Tank 48 is then drawn from Clear Water Storage Tank 48 and delivered to Stone Processing Tools 14B through Clear Water Supply Line 24 by a Crystal Clear Water Supply Pump 50. As also shown and described herein above, the Clear Water 42 outputs of the High Pressure Filters 46 of the High Capacity Filter Units 46UA - Un are also connected to Cleaning System Storage Tank 118 so that the High Pressure Filters 46 of the High Pressure Filter Units 46U can be cleaned and charged with filter media as described herein above. In this regard, it will be understood that piping and appropriate valves can be arranged between the High Pressure Filter Units 46U and Cleaning System Storage Tank 118 to allow the High Pressure Filters 46 to be cleaned and charged individually or in any selected combination.

[146] In a present exemplary embodiment of the present invention each High

Pressure Filter 46 has a filter capacity of, for example, approximately 20 cubic feet and uses filter plates no larger than approximately 800 - 1 ,000 mm diameter. As described, each High Pressure Filter Unit 46U thereby has a potential average flow rate capacity of approximately 7.5 gpm for each cubic foot of filter capacity, or up to 150 gpm for a 20 cubic foot capacity filter. The High Capacity Filter Assembly 46A therefore has a potential filter flow capacity equal to the sum of the potential potential flow capacities of the individual High Pressure Filter Units 46UA - 46Un. In the present example, for example, the potential filter flow capacity of the High Capacity Filter Assembly 46A would be N x F wherein N is the number of High Pressure Filter Units 46UA - 46Un and F is the potential flow capacity of each High Pressure Filter Unit 46U, so that the potential filter flow capacity of the exemplary High Capacity Filter Assembly 46A would be N x (150 gpm). It will also be understood that not all of the High Pressure Filter Units 46UA - 46Un in a High Capacity Filter Assembly 46A need be of the same capacity, or have a capacity of 150 gpm, and that the capacity of High Capacity Filter Assembly 46A can be tailored to specific requirements by corresponding selection of the number and capacities of the High Pressure Filter Units 46UA - 46Un comprising the High Capacity Filter Assembly 46A.

[147] A further aspect of the construction of a High Capacity Filter Assembly

46A is, as discussed herein above, the progressive decrease in the flow rate through the High Pressure Filters 46 of the High Pressure Filter Units 46U as the filter elements become filled with particulate matter. In the present exemplary embodiment of a High Capacity Filter Assembly 46A, however, and for example, it is desired to maintain an average flow rate of approximately 7.5 gpm for each cubic foot of filter capacity to thereby provide an average flow rate of 100 to 150 gpm from a 20 cubic foot filter press. That is, the exemplary High Capacity Filter Assembly 46A is to maintain an average flow rate of 100 to 150 gpm from each High Pressure Filter Unit 46U even when the High Pressure Filters 46 approaches their maximum planned capacity for accumulated particulate matter.

[148] It is understood by those of ordinary skill in the relevant arts that the significant factors in determining the flow rate through a High Pressure Filter 46 is the flow rate delivered by the input pump to the High Pressure Filter 46 and the input pressure provided by the input pump to drive the fluid and particulate matter through the filter elements against the back pressure that results within the High Pressure Filter 46. That is, the input pressure provided by a pump feeding a High Pressure Filter 46 must be sufficiently greater than the back pressure of the High Pressure Filters 46 to generate the desired flow rate through the filter elements wherein the back pressure arises from the flow resistance through the filter elements themselves plus the flow resistance resulting from the accumulation of particulate matter in the filter elements. In this regard, it must be noted that the flow resistance resulting from the accumulation of particulate matter in the filter elements will increase with time from some initial minimum value to a maximum value when the filter elements are filled to capacity with particulate matter.

[149] For example, in the case of a Water Treatment And Recycling System 10 or 1OG, a High Pressure Filter 46 of approximately 20 cubic feet capacity will present approximately 5 to 10 psi of backpressure when the filtering apparatus is clean and the Air Diaphragm Pump 44 will consume approximately 5 scfm of compressed air. When the filter apparatus in High Pressure Filter 46 is effectively full of particulate matter, the High Pressure Filter 46 will present, for example, approximately 80 psi of backpressure and the Air Diaphragm Pump 44 will consume up to 140 scfm of compressed air.

[150] In order to accomplish the object of the present invention, therefore, that is, to significantly increase the clear water production capacity of a Water Treatment And Recycling System 10 or 10GH to 100 to 150 gpm or greater, the High Capacity Water Treatment And Recycling System 10H must significantly increase the flow rate and pressure of Waste Water 26 into the High Pressure Filters 46 of the High Capacity Filter Assembly 46A. According to the present invention, this is accomplished in a High Capacity Water Treatment And Recycling System 10H by correspondingly increasing the flow rate and pressure capacities of the pumps driving the High Pressure Filters 46 by replacing the Air Diaphragm Pumps 44 employed in Water Treatment And Recycling Systems 10 and 10G with Duplex Air Diaphragm Pump Assembly 44D.

[151] As illustrated in Figs. 5A and 5B, 6 and 7 a Duplex Air Diaphragm Pump

44D is essentially comprised of a pair of Air Diaphragm Pumps 44 having parallel and parallel connected input and outputs and driven from a common power source, that is, a common air source, with common control circuits. The result is a 3" air driven pump capable, for example, of producing 90 psi (pounds per square inch) of pump backpressure up to 100 gpm and 80 psi of pump backpressure at up to 150 gpm. The flow and pressure capacities of the Duplex Air Diaphragm Pump Assembly 44D are thereby significantly increased over those of a single Air Diaphragm Pump 44, and are capable of driving a High Pressure Filter 46 to the flow rates and pressures required by larger stone processing facilities requiring significant quantities of crystal clear water. Since certain changes may be made in the above described method and system without departing from the spirit and scope of the invention herein involved, it is intended that all of the subject matter of the above description or shown in the accompanying drawings shall be interpreted merely as examples illustrating the inventive concept herein and shall not be construed as limiting the invention.

Claims

What is claimed is:

1. A water treatment and recycling system for providing clear water to clear water stone fabrication equipment, comprising: a waste water storage tank connected to receive and store grey water from discharge ports of the clear water stone fabrication equipment, a clear water supply loop, including a high capacity filter assembly having an input port connected from the waste water storage tank to receive waste water from the waste water storage tank and to convert the waste water into the clear water, a clear water storage tank connected from a discharge port of the high capacity filter assembly to receive and the store clear water from the high capacity filter assembly, and a clear water supply pump connected from the clear water storage tank for providing clear water from the clear water storage tank to the clear water stone fabrication equipment, wherein the high capacity filter assembly includes at least one high pressure filter unit, each high pressure filter unit including a duplex air diaphragm pump assembly having input ports connected to pump the waste water from the waste water storage tank, and cleaning system storage tank, and a high pressure filter for filtering the waste water into clear water and having an input port connected from an output port of the duplex air diaphragm pump assembly and an output port connected to provide the clear water to the clear water storage tank.

2. The water treatment and recycling system of claim 1 , wherein: each high pressure filter has a capacity of no greater than 20 cubic feet and an average flow rate of approximately 7.5 gpm for each cubic foot of filter capacity and includes filter plates no larger than 800 mm - 1 ,000 mm diameter.

3. The water treatment and recycling system of claim 1 , wherein: each duplex air diaphragm pump assembly has an air pressure maximum capacity of 100 psi. At 100 psi of air pressure, with air pump liquid back pressures of 90 and 100 psi (as examples), the duplex air diaphragm pump assembly will generate a combined discharge flow rate of 100 and 150 gpm respectively, provided the volume of air delivered to the air pump assembly reaches 105 and 180 scfm respectively.

4. The water treatment and recycling system of claim 1 , further comprising: a grey water supply loop for providing grey water to grey water stone fabrication equipment, including the waste water storage tank connected to receive and store grey water from discharge ports of the grey water stone fabrication equipment, and a grey water pump connected from the waste water storage tank for pumping waste water from the waste water storage tank as grey water to an input port of the grey water stone fabrication equipment, and

5. The water treatment and recycling system of claim 1 , further including: a filtered grey water supply loop for providing filtered grey water to filtered grey water stone fabricating equipment, including a grey water pump connected from the waste water storage tank for pumping waste water from the waste water storage tank as grey water, and a filtered grey water filter path connected from a grey water output of the grey water pump and having a separation filter for removing large particulate waste from the grey water, the separation filter having a filtered grey water output connected to an input port of a filtered grey water stone fabrication equipment and discharging the large particulate waste into the waste water storage tank.

6. The water treatment and recycling system of claim 5, wherein the grey water filter path further comprises: a particle filter for filtering smaller particulate matter from the filtered grey water.

7. The water treatment and recycling system of claim 1 wherein each high pressure filter includes: a frame holding a filter stack including a head plate, a plurality of filter plates, a tail plate and a ram for applying axial pressure along the filter stack to force the head plate, the filter plates and the tail plate into a pressure tight assembly, the head plate and each of the filter plates including an axial input bore connecting sequentially along the filter stage to form an axial input passage for receiving waste water from the waste water storage tank, and a plurality of discharge bores located circumferentially around the axial input passage to form a corresponding plurality of discharge passages extending along the length of the filter stack, the discharge passages being connected to one another outside of the head plate and to the clear water storage tank, and each of the filter plates further including at least one filter chamberfor containing and supporting active filter elements, each filter chamber being connected between the axial input passage and each of the plurality of discharge passages and the active filter elements removing particulate matter from the waste water flowing along the input passage to provide the crystal clear water discharged through the discharge passages, and the tail plate being located at the opposite end of the filter stack from the head plate and terminating the input passage and the discharge passages.

8. The water treatment and recycling system of claim 7, wherein the active filter elements comprise: a filter media extending across a filter chamber in a flow path between the input passage and the discharge passages communicating with the filter chamber, and a granular filter layer coated upon and supported by the filter media for removal of particulate matter from the waste water and protection of the filter media, the granular filter layer being located in the flow path from the input passage to the discharge passages on the input passage side of the filter media.

9. The water treatment and recycling system of claim 7, further comprising: in each filter plate, a filter chamber gasket circumferentially surrounding at least one filter chamber to seal the at least one filter chamber to a next sequential one of a filter plate, the head plate and the tail plate, and a discharge bore gasket circumferentially surrounding each discharge bore on one face of the filter plate to seal each discharge bore to a next sequential one of a filter plate, the head plate and the tail plate.

10. A method for providing clear water to clear water stone fabrication equipment, comprising: receiving and storing grey water from discharge ports of the clear water stone fabrication equipment in a waste water storage tank, filtering the waste water into clear water in a high capacity filter assembly including at least one high capacity filter unit including, in each high capacity filter unit, the steps of pumping the waste water from the waste water storage tank through a duplex air diaphragm pump assembly having input ports connected to pump the waste water from the waste water storage tank, and filtering the waste water into the clear water through a high pressure filter having an input port connected from an output port of the duplex air diaphragm pump assembly, storing the clear water in a clear water storage tank connected from an output port of the high pressure filter, and providing the clear water from the clear water storage tank and to the clear water stone fabrication equipment through a clear water supply pump connected from the clear water storage tank.

11. The water treatment and recycling system of claim 10, wherein: each high pressure filter has a capacity of no greater than 20 cubic feet and an average flow rate of approximately 7.5 gpm for each cubic foot of filter capacity and includes filter plates no larger than 800 mm - 1 ,000 mm diameter.

12. The water treatment and recycling system of claim 10, wherein: each duplex air diaphragm pump assembly has an air pressure maximum capacity of 100 psi. At 100 psi of air pressure, with air pump liquid back pressures of 90 and 100 psi (as examples), the duplex air diaphragm pump assembly will generate a combined discharge flow rate of 100 and 150 gpm respectively, provided the volume of air delivered to the air pump assembly reaches 105 and 180 scfm respectively.

13. The method for providing clear water to clear water stone fabrication equipment of claim 10 further comprising a method for providing grey water to grey water stone fabrication equipment, including the steps of: providing grey waterto the grey water stone fabrication equipment through a grey water loop, including the steps of pumping the waste water from the waste water storage tank as grey water through a grey water pump connected from the waste water storage tank, and providing the grey water to the grey water stone fabrication equipment from an output port of the grey water pump.

14. The method for providing clear water to clear water stone fabrication equipment of claim 10 further comprising a method for providing filtered grey water to filtered grey water stone fabrication equipment, including the steps of: providing the filtered grey water to the grey water stone fabrication equipment through a filtered grey water loop, including the steps of pumping the waste water from the waste water storage tank as grey water through a grey water pump connected from the waste water storage tank, filtering the grey water into filtered grey water through a separation filter for removing large particulate waste from the grey water, and providing the filtered grey water from the separation filter and to the filtered grey water stone fabrication equipment and discharging the large particulate waste into the waste water storage tank

15. The method for providing clear water to clear water stone fabrication equipment of claim 14, further comprising the step of: removing smaller particulate matter from the grey water in a particle filter connected between the separation filter and the filtered grey water stone fabrication equipment.

16. The method of claim 10 for providing clear water to clear water stone fabrication equipment wherein the step of filtering the waste water into the clear water includes, in each of the at least one high capacity filter unit, the steps of:: passing the waste water through a high pressure filter stack that includes a head plate, a plurality of filter plates and a tail plate in a filter frame wherein the head plate, the filter plates and the tail plate are forced into a pressure tight assembly by axial pressure along the filter stack, including the steps of supplying waste water under pressure into a waste water input passage of the filter stack wherein the head plate and each of the filter plates include an axial input bore connecting sequentially along the filter stage to form an axial waste water input passage for receiving waste water from the waste water storage tank, passing the waste water through each of at least one filter chamber in each of the filter plates wherein each filter chamber contains and supports active filter elements for removing particulate matter from the waste water to convert the waste water into crystal clear water, each filter chamber being connected between the axial waste water input passage and each of a plurality of discharge passages, collecting the crystal clear water in each of the discharge passages and passing the crystal clear water in the discharge passages through the head plate and to an input port of the crystal clear water storage tank, wherein the head plate includes a plurality of discharge ports, each discharge port being connected to a corresponding discharge passage of the filter stack, and the tail plate is located at the opposite end of the filter stack from the head plate and terminates the input passage and the discharge passages.

17. The water treatment and recycling system of claim 16, wherein the active filter elements comprise:

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RECnTOSHEET(RUIi OI) a filter media extending across a filter chamber in a flow path between the input passage and the discharge passages communicating with the filter chamber, and a granular filter layer coated upon and supported by the filter media for removal of particulate matter from the waste water, the granular filter layer being located in the flow path from the input passage to the discharge passages on the input passage side of the filter media.

18. The water treatment and recycling system of claim 16, further comprising: in each filter plate, a filter chamber gasket circumferentially surrounding at least one filter chamber to seal the at least one filter chamber to a next sequential one of a filter plate, the head plate and the tail plate, and a discharge bore gasket circumferentially surrounding each discharge bore on one face of the filter plate to seal each discharge bore to a next sequential one of a filter plate, the head plate and the tail plate.

19. The method of claim 16, further including a method for cleaning the filter stack of accumulated waste particulate matter, comprising the steps of: forcing air into the filter stack through a discharge passage to force air to flow through the filter chambers and the active filter elements to and through another discharge passage to force water from particulate waste matter captured by the active filter elements, releasing axial pressure on the filter stack to permit separation of the head plate, the filter plates and the tail plate, scraping the particulate waste matter captured by the active filter elements and a granular filter layer containing the captured particulate waste matter from the surface of a filter cloth or media, flushing captured particulate waste matter from the surface of the filter media by means of a high pressure water hose system, reassembling the head plate, the filter plates and the tail plate into a filter stack and restoring the axial pressure on the head plate, the filter plates and the tail plate to force the filter stack into a pressure tight assembly, flushing crystal clear water through the filter stack in the normal direction to flush residual waste matter from the filter stack by forcing crystal clear water into the input passage to flow through the filter plates and out the discharge passages, and restoring the granular filter layer coating to each filter cloth or media.

20. The method of claim 19 further including a method for coating a granular filter layer onto each filter media, comprising the steps of: pumping a mixture of crystal clear water and a granular material comprising the granular filter layer into the input passage of the filter stack to flow through each filter media of each filter plate and through the discharge passages from the filter stack, and recirculating the crystal clear water returned from the discharge passages of the filter stack and replenishing the granular material mixed into the crystal clear water until a desired thickness of the granular material is deposited on the each filter media of each filter plate.

21. The method of claim 16 wherein each filter plate includes a filter media coated with a granular filer layer for filtering the particulate waste matter from the waste water to convert the waste water into crystal clear water, further comprising a method for depositing a granular filter layer on each filter media, comprising the steps of: pumping a mixture of crystal clear water and a granular material comprising the granular filter layer into the input passage of the filter stack to flow through each filter media of each filter plate and through the discharge passages from the filter stack, and recirculating the crystal clear water returned from the discharge passages of the filter stack and replenishing the granular material mixed into the crystal clear water until a desired thickness of the granular material is deposited on the each filter media of each filter plate.

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RECTfRED SHEET (RULE 91)