AU2004202855A1 - Improved separator for immiscible liquids - Google Patents

Description

P/00/011 Regulation 3.2

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION STANDARD PATENT Invention Title: Improved separator for immiscible liquids The following statement is a full description of this invention, including the best method of performing it known to us: Freehills Carter Smith Beadle Sydney\004665399 Printed 25 June 2004 (14:11) Freehills Carter Smith Beadle Sydney\004665399 Printed 25 June 2004 (14:11) 004664641v3 2 IMPROVED SEPARATOR FOR IMMISCIBLE LIQUIDS FIELD OF THE INVENTION [0001] This invention relates in general to a liquid separation devices and, more particularly, to a device for separating oils and/or grease from water.

BACKGROUND OF THE INVENTION [0002] In several industries, and in particular the food industry, there is a need to separate liquid greases, fats and oils from waste water prior to passing the water to the sewage system. The waste water could be, for example, discharge from a washing device for cleaning dinnerware and cooking utensils. If the greases and fats solidify in the sewage system, a blockage can occur which is expensive to remediate.

[0003] Additionally, there is a movement in many localities to recycle grease and oils.

[0004] A commercially available separation device of the type described in European Patent EP 890381 B1 is shown generally in Figures la and lb. Figure la illustrates an exterior perspective view of the separation device 10. Effluent (containing two or more immiscible liquids of different densities, typically water entrained with oil, grease dissolved fats and other particles) is received at inlet 12 providing a passage into housing 14 (including removable lid 15). Effluent is heated using a probe-type heater 16, which is coupled to an electrical connection. As described below, the immiscible liquids separate within housing 14, and the less dense material grease and oils) empties into container 18. The more dense 004664641v3 3 liquid water) is discharged from water outlet 20. Silt may accumulate at the bottom of housing 14. The silt may be periodically discharged through silt outlet 22.

[0005] Operation of the separation device 10 is described in greater detail in connection with Figure lb (as well as EP 890381 B1, which is incorporated by reference). Figure lb illustrates a cross-sectional side view of the separation device A coarse filtration chamber 24 is defined between the housing 14 and control plate 25, which extends the full width of the housing. As effluent enters the coarse filtration chamber 24 through inlet 12, it passes through a filtering basket 26 (shown in greater detail in connection with Figure which filters out solid particles, such as undissolved fat and other food particles.

[0006] After passing through the basket 26, the effluent enters the separation chamber 28, defined by control plate 25, control plate 30 (which extends the full width of the housing), top plate 32 and the bottom of housing 14. There are two exits from the separation chamber: through floating ball valve 34 and through passage 36, disposed between the bottom of control plate 30 and the bottom of the housing 14. Top plate 32 is angled upward from the bottom portion of control plate towards control plate [0007] Weir plate 38, which extends the full width of the housing, defines a water (high density liquid) release chamber 40, along with control plate 30 and the housing 14. Outlet 20 is disposed through the housing.

[0008] In operation, as the effluent enters the separation chamber 28, the lower density liquid (grease/oil) rises. The flow through the separation chamber 28 is set at a rate that allows the lower density liquid to separate from the water and float upwards to the surface of the water, where it is contained below the sloping top plate 32.

[0009] The sloping top plate 32 forces the lower density liquid to accumulate at the entry to floating ball valve 34. Floating ball valve 34 is shown in greater detail in connection with Figure 4. Floating ball valve 34 uses a ball that floats at the 004664641v3 4 interface between the high density liquid and the low density liquid. When the high density liquid reaches a predetermined height, the ball rises to a height which stops flow from the separation chamber 28 to the container 18.

[0010] As the water flows through the separator 10, it must rise above the top of weir 38 in order to exit. Accordingly, the water in separation chamber 28 attempts to rise to approximately the same height. Since the top of the separation chamber 28 is below the top of weir plate 38, the hydrostatic pressure of the upward force of the water will push the separated grease/oil at the top of the separation chamber 28 through valve 34. The water, however, cannot pass through the valve 34, because the floating valve will stop its passage. Hence, once all the separated grease/oil is forced out of the separation chamber, the valve will remain closed until more grease/oil accumulates.

[0011] The separated water passes through passage 36, over weir plate 38 and out outlet 20. Silt in the water tends to accumulate at the bottom of housing 14, unable to rise over weir plate 38. Silt valve 22, located at the bottom of housing 14, can be opened periodically, and the flow of water out of the valve will flush out the silt.

[0012] In many fields of use for the separator 10, and in particular the food industry, it can be assumed that the employees who will operate and maintain the separator will be relatively transient between employers. Accordingly, aspects of the operation and maintenance of the separator must allow for unfamiliarity with details.

Matters such as periodic cleaning of various components of the separator, such as the floating ball valve, if performed incorrectly, can lead to unwanted consequences, such as allowing water to exit into the oil/ grease container or oil/ grease flowing out of the outlet [0013] Also, it would be beneficial to improve the flow of liquids through the separation chamber, since oil and grease are by their nature sticky and tend to accumulate on hard surfaces.

004664641v3 [0014] Accordingly, there is a need in the industry for an improved separator.

BRIEF SUMMARY OF THE INVENTION [0015] In one aspect of the present invention, a separator for immiscible liquids includes a tank having an inlet, an inlet chamber, a separation chamber and an outlet chamber, with the inlet feeding effluent into the inlet chamber, the inlet chamber being in communication with the separation chamber through a first passage and the separation chamber being in communication with the outlet chamber through a second passage. A basket having at least one tapered side disposed in the inlet chamber below the inlet, such that the one tapered side is disposed at an angle relative to an adjacent sidewall of the inlet chamber.

[0016] In a another aspect of the present invention a separator for immiscible liquids comprises a tank having an inlet, an inlet chamber, a separation chamber and an outlet chamber, with the inlet feeding effluent into the inlet chamber, the inlet chamber being in communication with the separation chamber through a first passage and the separation chamber being in communication with the outlet chamber through a second passage; a basket disposed in the inlet chamber below the inlet; and a baffle disposed above said basket for deflecting effluent from said inlet into the basket. In this aspect the baffle directs effluent into the basket with greater force.

[0017] In another aspect of the present invention, a separator for immiscible liquids comprises a tank having an inlet, an inlet chamber, a separation chamber and an outlet chamber, with the inlet feeding effluent into the inlet chamber, the inlet chamber being in communication with the separation chamber through a first passage and the separation chamber being in communication with the outlet chamber through a second passage; an oil/ grease outlet valve replaceably disposed in a valve housing coupled to said separation chamber, said valve having an interlocking connection to the valve housing.

004664641v3 6 [0018] In another aspect of the present invention, a separator for immiscible liquids comprises a tank having an inlet, an inlet chamber, a separation chamber and an outlet chamber, with the inlet feeding.effluent into the inlet chamber, the inlet chamber being in communication with the separation chamber through a first passage and the separation chamber being in communication with the outlet chamber through a second passage, wherein effluent separates into a denser fluid and a less dense fluid in the separation chamber and an oil/grease outlet valve disposed in said separation chamber. The valve comprises a sensor for sensing a height of said denser fluid in said separation chamber, a valve and an actuator for opening and closing said valve responsive to said sensor.

[0019] In another aspect of the present invention, a separator for immiscible liquids comprises a tank having an inlet, an inlet chamber, a separation chamber and an outlet chamber, with the inlet feeding effluent into the inlet chamber, the inlet chamber being in communication with the separation chamber through a first passage and the separation chamber being in communication with the outlet chamber through a second passage, wherein effluent separates into a denser fluid and a less dense fluid in the separation chamber; a valve for releasing the less dense fluid from said separation chamber; and a heat blanket proximate to the bottom of the tank.

[0020] In another aspect of the present invention, a separator for immiscible liquids comprises a tank having an inlet, an inlet chamber, a separation chamber and an outlet chamber, with the inlet feeding effluent into the inlet chamber, the inlet chamber being in communication with the separation chamber through a first passage and the separation chamber being in communication with the outlet chamber through a second passage, wherein effluent separates into a denser fluid and a less dense fluid in the separation chamber; a valve for releasing the less dense fluid from said separation chamber; and flexible hollow tubing disposed about the bottom of the tank for creating a seal with the floor to prevent liquid from seeping below the tank.

004664641v3 7 [0021] In another aspect of the present invention, a separator for immiscible liquids comprises a tank for disposal in the ground, said tank having an inlet, an inlet chamber, a separation chamber and an outlet chamber, with the inlet feeding effluent with entrained silt into the inlet chamber, the inlet chamber being in communication with the separation chamber through a first passage and the separation chamber being in communication with the outlet chamber through a second passage, wherein effluent separates into a denser fluid and a less dense fluid in the separation chamber, wherein the separation chamber is defined within a housing by an inlet control plate, an outlet control plate and an upper control plate; a valve disposed through the upper control plate for passing the less dense fluid above the upper control plate for removal; a heater disposed through the upper control plate, such that the heater, valve and less dense fluid for removal can be accessed through a lid on top of the housing.

[0022] In another aspect of the present invention, a separator for immiscible liquids comprises a tank for disposal in the ground, said tank having an inlet, an inlet chamber, a separation chamber and an outlet chamber, with the inlet feeding effluent with entrained silt into the inlet chamber, the inlet chamber being in communication with the separation chamber through a first passage and the separation chamber being in communication with the outlet chamber through a second passage, wherein effluent separates into a denser fluid and a less dense fluid in the separation chamber; a valve disposed in the separation chamber for passing the less dense fluid; and a storage tank for storing the less dense fluid from the valve. The storage tank has at least one access port for receiving waste fluids and for collection of fluids from the tank. This aspect provides a dual purpose tank that can be used to store both separated oil and oil from operations for common removal.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS [0023] For a more complete understanding of the present invention, and the advantages thereof, reference is now made to the following descriptions taken in conjunction with the accompanying drawings, in which: 004664641v3 8 [0024] Figures la and lb illustrate a perspective view and a cross-sectional view of a prior art separation device; [0025] Figure 2 illustrates a prior art filtration basket used in the device of Figures la and Ib; [0026] Figures 3a through 3d respectively illustrate perspective, top, crosssectional front, and cross-sectional side views of an improved basket; [00271 Figure 4 illustrates a prior art floating ball valve used in the separation device of Figures la and Ib; [0028] Figure 5a illustrates a cross-sectional view of an improved floating ball valve; [0029] Figure 5b illustrates a perspective view of a housing for an improved floating ball valve; [0030] Figure 5c illustrates a top view of the improved floating ball valve; [0031] Figure 6a illustrate a block diagram of an improved valve for replacing the ball valve of Figure 4; [0032] Figures 6b through 6d illustrate cross-sectional view of butterfly, gate and ball valves, respectively; [0033] Figures 7a through 7c illustrates an improved separation device with low friction surfaces, improved heating and silt removal, and leakage prevention; [0034] Figure 8 illustrates an improved separation device that can be used in an in-ground installation; [0035] Figure 9 illustrates a tool for cleaning the separation device of Figure 8; [0036] Figure 10 illustrates a separation device combined with a large capacity storage container for unified grease control; and 004664641v3 9 [0037] Figure 11 illustrates a bi-directional separation device.

DETAILED DESCRIPTION OF THE INVENTION [0038] The present invention is best understood in relation to Figures 1 11 of the drawings, like numerals being used for like elements of the various drawings.

[0039] Figure 2 illustrates a prior art filtration basket 26. The basket has a front side (facing the housing at inlet 12) and a back side (facing control plate 25) that is perforated with holes 50, as is the bottom of the basket. Since the front side is relatively flush with housing 14 and the back side is relatively flush with control plate 25, and the ends are not perforated, almost all of the effluent flow is through the holes in the bottom of the basket. Over time, food particles will accumulate on the bottom of the basket 26, severely limiting flow into the separation chamber 28.

[0040] Other problems concern removal and replacement of the basket 26. The prior art uses a handle 52 which terminates through holes on either side of the basket. The basket 26 has flanges 54 on either side; flanges 54 normally rest on support clips 56 formed on either side of the housing in the coarse filtration chamber 24. In order to accommodate the exposed ends of the handle 52 when the basket is removed or replaced, slots 58 are formed in support clips 56 through which the ends of the handle may pass.

[0041] During operation, the slots 58 prevent a complete seal between flanges 54 and support clips 56. Some of food particle in the effluent may pass through the slots 58, bypassing basket 26. Food particles may also pass through the narrow gap between the front edge of the basket and the outer body 14 and the rear edge of the basket and the control plate 25. Excessive food particles entering the separation chamber 28 can clog the floating ball valve 34, resulting in water passing into the oil collection chamber 18.

[0042] Figures 3a through 3d illustrate perspective, top, cross-sectional front and cross-sectional side views of an improved basket 60. The improved basket 004664641v3 increases efficient effluent flow, eliminates solid particles in the effluent from bypassing the filtration mechanism of the basket, and enhances effluent separation in the separation chamber 28.

[0043] As distinguished from the vertical sides of basket 26, tapered basket has tapered sides that angle away from housing 14 and control plate 25. Further, all four sides are perforated. Accordingly, a larger surface area of the basket is separated from a constricting wall for more efficient flow through the basket Since there is more area for holes 62, the holes 62 can have a smaller diameter, without affecting flow of effluent through the basket. In the prior art, holes 50 had a diameter of approximately 11/64 inches, while holes 62 can have a diameter of approximately 1/16 inches (0.15875 cm). This allows smaller particles to be trapped by the basket 60 for more effective coarse filtering. Further, more debris may be collected before the basket needs to be emptied, since the basket will continue to efficiently filter the effluent even when the bottom is covered.

[0044] An additional improvement is the addition of inclined baffle plate 64 to the basket 60. Baffle plate 64 deflects water from inlet 12 towards the bottom of the basket 60. A cut-out 64a in the baffle plate 64 faces inlet 12. As effluent enters the coarse filtering chamber 24, the baffle directs the effluent downwards to help drive oils and grease under the control plate 25. Further, as effluent hits the baffle plate 64, it is driven through a layer of oil, which helps to saturate the chemical emulsions, causing the emulsions to release the oil.

[0045] The handle 68 of basket 60 is attached to the top of the baffle plate 64.

Because the handle does not protrude from the sides of the basket 60, the slots 58, shown in Figure 2 are no longer necessary.

[0046] With the addition of the baffle plate 64, it is important that the basket is oriented correctly (such that the baffle plate deflects effluent downward, not upward). A careless replacement of the basket 60 could thus cause problems with the operation of the separator 10. To prevent an errant replacement, the basket 004664641v3 11 has asymmetric flanges 54a and 54 b. As shown in Figures 3a-d, flange 54a is wider than 54b, and support clip 56a is wider than 56b. If the basket 60 is replaced in the reverse orientation, the mismatch between the support clips 56a-b and flanges 54a-b will not allow the basket to seat properly (and the lid will not be able to close). This will notify the operator that the basket needs to be reversed. Front and back flanges 54c and 54d provide an integral lip that completely surrounds the basket 60 for a complete seal.

[0047] Figure 4 illustrates a type of floating ball valve 34 used in the prior art.

Floating ball valve 34 includes a ball 70 within housing 72. Ball 70 is held within housing 72 by a grid 74. Insert 76 includes a mating portion 78 for mating with the housing 72 above the ball 70 and an outlet portion 79 for communicating with the oil/grease container 18. A passage 80 is formed in insert 76 through the mating portion 78 and outlet portion 79, with a tapered opening 82 at the end of the passage Passage 80 is coupled to outlet 84. O-ring 86 seals mating portion 78 and housing 72. As described above, the ball 70 is designed to float at the interface between two immiscible liquids water and oil/grease). As the water rises, the oil/grease is pushed into passage 80, where it exits to the oil/grease container 18 via outlet 84.

Once all of the lower density liquid (oil/grease) has been pushed into the passage the ball 70 presses against the tapered opening 82, thereby closing the passage. In this way, only the lower density liquid can pass through the passage [0048] Since the oils and grease will pass through the passages 80 and 84 to the oil/grease container 18, the passages 80 and 84 need to be cleaned periodically to remove congealed substances. To do so, a brush is inserted into the passage 80 from above or passage 84 from the side and an up and down scrubbing motion is used to dislodge the congealed oil/grease within the passage 80. During the cleaning process, the mating portion 78 can easily become dislodged from the housing 72, causing failure of the valve 34.

[0049] In Figures 5a illustrates a cross-sectional side view of an improved floating ball valve 90, which can be used in place of floating ball valve 34. Floating 004664641v3 12 ball valve 90 includes a mating portion 78, with two protruding locking pins 92.

Housing 72 includes two vertical channels 94 forming L-shapes with respective horizontal channels 96 (see Figure 5b) to accept pins 92. The mating portion 78 is engaged within housing 72 by aligning the pin 92 with vertical channel 94, inserting the mating portion 78 into the housing 72 until pin 92 reaches the end of the vertical channel 94, then rotating the pin within the horizontal channel 96 to lock the mating portion within the housing 72.

[0050] Figure 5b shows a perspective view of housing 72, illustrating the vertical channel 94 and horizontal channel 96. Figure 5c illustrates the insert 76 in a locked position within housing 72.

[0051] Another problem associated with floating ball valve 34 is the problems which can occur if the ball 70 sticks to the mating portion 82. This is possible because of the oil/grease that will coat both surfaces during normal operation of the separator [0052] Figure 6a illustrates a schematic of an alternative embodiment of a valve which can be used to eliminate the need for a floating ball. In Figure 6a, a sensor 100 senses the location of the interface between the two immiscible liquids.

When the interface has reached a predetermined level, the sensor sets a control signal to actuator 102. Responsive to the control signal, the actuator closes a valve 104 which controls flow between an oil/grease inlet 106 and an oil/grease outlet 108.

[0053] Figures 6b through 6d illustrate three types of valves that could used implement valve 104 (other valve types could be used as well). Figure 6b illustrates a cross-sectional side view of a butterfly valve 110. The butterfly valve operates by rotating a disk 114 within cylindrical housing 112. When surface the disk 114 is aligned parallel to the axis of the cylindrical housing, the valve 110 is in an open state; when the surface of the disk 114 is perpendicular to the axis of the cylindrical housing 112, the valve 110 is in a closed state.

004664641v3 13 [0054] Figure 6c illustrates a cross-sectional side view of a gate valve 120. In a gate valve, a gate 122 is positioned within tube 124 to prevent flow and withdrawn from tube 124 to allow flow.

[0055] Figure 6d illustrates a cross-sectional side view of a ball valve 130 (not to be confused with the floating ball valve 34). The ball valve incorporates a sphere 132 with a cylindrical bore 134 disposed through the center of the sphere. When the bore is aligned with the inlet 136 and outlet 138, liquid can pass from inlet to outlet.

When the bore 134 is rotated to a position where it does not communicate between inlet 136 and outlet 138, liquid can no longer pass through the valve.

[0056] The ball valve 130 is a preferred embodiment for the present invention, because the operation of the valve rotating between opened and closed positions tends to scrape away congealed oil/grease at the inlet and outlet. Therefore, this valve is somewhat self-cleaning.

[00571 Figure 7a illustrates improvements made to the separator 10 to improve flow of the liquids (and silt) inside the separation chamber for improved operation.

First, the inside of housing 14 and surfaces of control plate 25, top plate 32, control plate 30 and weir 38 can be coated with a Teflon layer 39, or another non-stick coating layer 39, in improve flow and reduce friction and adhesion between the oil/grease/silt and these surfaces.

[0058] Additionally, Figure 7a illustrates improvements made to heating of the liquids, particularly in the separation chamber 28. In the prior art, a probe-type heating element has been used. This presents several problems. First, the heater is mounted to the outside of the unit, where it can be inadvertently hit by employees, and knocked loose. Second, the surface area of the heater is relatively small and, therefore, the heat is localized.

[0059] In Figure 7a, several alternatives are shown for heating the liquids in the separation chamber 28. These alternatives could be used separately or combined.

The first alternative uses a heating blanket 140 disposed on the bottom of housing 14.

004664641v3 14 This eliminates any protruding housing for the heater and heats a larger surface area, keeping the temperatures relative constant across the separation chamber 28.

[0060] A second alternative uses induction heating to heat the top plate 32 and/or valve 34. Since the top plate 32 and valve 34 are in nearly constant contact with the oil/grease, these elements can be heated by induction to most effectively provide heat for keeping the oil/ grease as liquid as possible. The induction heating of the top plate 32 and/or valve 34 could be used in conjunction with the heat blanket 140.

[0061] Additionally, in Figure 7a, a self-closing valve 147 is used as the silt valve. After being placed in an open position to flush out silt, the self-closing valve will close without further manual interaction in 2-20 seconds, or other time which is sufficient to remove the silt. This protects the device from being operated with the silt valve open, which could allow effluent to pass directly out the silt valve; this could cause the heater to overheat and to burn out and/or cause the oil to overheat and smoke.

[0062] Figures 7a, 7b and 7c illustrate top and bottom seals used in the improved separator. A top seal 142 is formed on the perimeter of the housing 14 and on the tops of control plates 25 and 30, providing a continuous seal. In the preferred embodiment, the seal 142 is mechanically attached to the housing 14 and control plates in the manner shown in Figure 7c. In Figure 7c, the seal material, preferably in the form of a hollow neoprene tube or similar flexible hollow tubing, is affixed to an edge of the housing 14 and control plates 25 and 30 using a mechanical gripping mechanism 144. In the illustrated embodiment, the mechanical gripping mechanism includes teeth 146 which, when pushed onto the housing edges, will grab the edges to form a strong mechanical bond. Any gaps between strips of materials should be filled with a sealing compound.

[0063] In operation, the top seal 142 can withstand considerable water pressure with just the weight of the lid 15 maintaining contact with the seal 142.

004664641v3 Thus, if an surge of water is received through inlet 20, water is maintained within the housing 14, and is kept from overflowing from either the coarse filtration chamber 24 or the water release chamber 40 into the interior chamber 148 of the housing 14, where it can become rancid.

[0064] Prior art mechanisms use a compressive foam that is affixed to the lower edge of the lid by means of a self adhesive strip, and a seal is created by the use of lid clamps to hold the lid to the body. The claims make the user access to the unit difficult. Also, the clamped lid discourages the operators from properly maintaining the unit.

[0065] An additional bottom seal 149 is affixed around the bottom edge of the housing 14. Once again, the bottom seal 149 is preferably in the form of a hollow neoprene tube affixed to the edges of the housing 14 using a mechanical gripping mechanism 144 as shown in Figure 7c.

[0066] Prior art methods for sealing the separator to a floor, such as by caulking, have adhesion problems, particularly in the grout lines. Since units will often be retrofit to existing restaurants, the grease embedded in the grout resists adhesion, allowing water from floor cleaning to seep under the unit. Also, caulking complicates moving of the unit. Placing the unit on legs such that the floor can be cleaned under the unit can add height to the unit, reducing the positive fall of the effluent from sink and dishwasher drains.

[0067] The bottom seal 149 has been shown to effectively seal the unit to the floor, and is particularly effective in sealing the grout lines, since the weight of the unit holds the bottom seal 149 firmly within the grout lines.

[0068] Figure 8 illustrates an embodiment of a separator 150 which has the advantage that it can be used in an in-ground embodiment. For illustration purposes, separator 150 is shown with the prior art heater 16 and floating ball valve 34, it being understood that the other improvements described herein could be used in the place of these elements.

004664641v3 16 [0069] In Figure 8, basket 60 performs coarse filtering on effluent received through inlet 12. Control plate 25 has an angled portion 152 to provide an improved flow through basket 60 (this improvement can be used in other configurations as well). A downward sloping bottom control plate 154 has a V-shape (or channel) to catch silt, and is preferably Teflon coated. The V-shape bottom control plate transitions into weir 156, maintaining a V-shape which is slanted upwards to the desired predetermined height to provide hydrostatic pressure on the separated oil at valve 34. Control plate 158, is coupled to the top of housing 14 and provides a channel 160 through which the separated water flows. Control plate 158 includes an enlarged portion 162. Heater 16 is disposed through top plate 32, within compartment 164. Apart from compartment 164, the area above top plate 32 can be used as a sump 166 to store oil/ grease from oil/ grease valve 34, preferably in a removable container. Access to the tapered basket 60, sump 166, compartment 164 and oil valve 34 can be made by removing one or more lids (not shown) on the top of housing 14. If silt is to be separate from the water, a water outlet 168 is placed above a silt valve 170. Alternatively, a single outlet can be provided, which disposes of both water and silt. A mesh screen 172 is positioned in front of water outlet 168 to filter out silt.

[0070] In operation, silt from the effluent will gather at the bottom plate 154, and will be drawn towards the lowest portion of the shaped plate 154 at the interface with the weir 156. The flow of water through channel 160 will push the silt up the channel 160. The enlarged portion 162 of the channel will create turbulence and additional suction to pull silt up and over the top of weir 156. Silt will fall to silt valve 170, which can be periodically opened to a silt outlet or collected separately in a container coupled to the silt valve 170. The remainder of the water flows out of water outlet 168 into the sewage system.

[0071] Over time, some silt may collect on weir 156. Figure 9 illustrates a scraper which matches the profile of weir 156 to remove this silt.

004664641v3 17 [0072] Preferably, all inside surfaces of separator 150 are Teflon coated to decrease resistance and improve flow.

[0073] Figure 10 illustrates a diagram of a separator with a large grease container for containing both grease/oil separated from the effluent and for containing used grease/oil from operations, such as from frying machines. In this embodiment, an underground separator 150 (an above ground separator of the type shown in Figures 1-7a-c could also be used) is coupled to a storage tank 170 which is large enough to hold all the discard oil/grease from effluent and operations. Pipe 172 couples the valve 34 to the storage tank 170. Opening 174 allows workers to pour the oil/grease into the storage tank from an oil caddy, for example. Alternatively, the oil/grease from operations could be pumped directly to the tank 170. Heater 176 heats the contained oil so that it does not solidify. Valve 178, typically a quick disconnect valve, provides a suitable connection to an oil pump used to pump oil/grease from the tank 170 for reclamation. Pipe 180 is disposed between valve 178 and the bottom of the tank 170.

[0074] In operation, the embodiment shown in Figure 10 allows a business to consolidate all oil/grease waste for removal by a collection company, typically an outside contractor or municipality. The unified design allows the collection company to collect all of the used oil/grease from a restaurant. By using the underground configuration, oil drums/dumpsters could be eliminated from the back of the restaurant, or other business.

[0075] Figure 11 illustrates an embodiment for an above-ground bidirectional separator 182 (with lid 15 removed), the valve 34 and heater 16 can be located on either side of the housing 14. The housing 14 includes two oil valve housings 72, one of which will receive a valve 34 and the other of which will have a plug installed.

Container 18 is mounted through opening 186 on the side of the valve 34, the other opening 186 is closed with a blank. The holes 186 have slotted holes adjacent to them to enable either the container 18 or support or blank plate to be mounted. Threaded 004664641v3 18 connections 188 are made on either side of the housing 14 for receiving the heater 16; the side not receiving the heater is closed with a threaded plug.

[00761 The embodiment shown in Figure 11 allows the separator 182 to be installed in either flow direction, which reduces the cost of inventory that must be maintained and allows the most efficient installation within a business. Further, the direction of the separator 182 can be switched if a kitchen is remodeled (on average, a commercial kitchen is remodeled every five years) to accommodate a change in flow through the pipes.

[0077] Although the Detailed Description of the invention has been directed to certain exemplary embodiments, various modifications of these embodiments, as well as alternative embodiments, will be suggested to those skilled in the art. The invention encompasses any modifications or alternative embodiments that fall within the scope of the Claims.

[0078] As used herein, the term "comprise" and variations of the term, such as "comprising", "comprises" and "comprised", are not intended to exclude other components or integers.

[0079] Reference to any prior art in the specification is not, and should not be taken as, an acknowledgment or any form of suggestion that this prior art forms part of the common general knowledge in Australia or any other jurisdiction.

Claims (31)

1. A separator for immiscible liquids comprising: a tank having an inlet, an inlet chamber, a separation chamber and an outlet chamber, with the inlet feeding effluent into the inlet chamber, the inlet chamber being in communication with the separation chamber through a first passage and the separation chamber being in communication with the outlet chamber through a second passage; a basket having at least one tapered side disposed in the inlet chamber below the inlet, such that the one tapered side is disposed at an angle relative to an adjacent sidewall of the inlet chamber.

2. A separator of claim 1 and further comprising a support flange disposed completely around the periphery of the inlet chamber and wherein said basket includes an integral flange around the periphery of the basket for resting upon said support flange.

3. A separator of claim 1 and further comprising a baffle disposed on said basket such that the baffle is located proximate the inlet, such that effluent entering through the inlet deflects off the baffle and into the basket.

4. A separator of claim 3 and further comprising a handle coupled to the baffle.

5. A separator of claim 4 and further comprising first and second side flanges on opposite sides of the basket for resting upon respective first and second support flanges disposed in said inlet chamber for holding said basket in place, wherein said first side flange and said first support flange have a first width and said second side flange and said second support flange have a second width larger than said first width.

6. A separator of claim 1 wherein said basket has four sides and a bottom, wherein holes are disposed through said sides and said bottom for filtering effluent. 004664641v3

7. A separator of claim 6 wherein said holes have a diameter of 1/16 inches or less.

8. A separator for immiscible liquids comprising: a tank having an inlet, an inlet chamber, a separation chamber and an outlet chamber, with the inlet feeding effluent into the inlet chamber, the inlet chamber being in communication with the separation chamber through a first passage and the separation chamber being in communication with the outlet chamber through a second passage; a basket disposed in the inlet chamber below the inlet; and a baffle disposed above said basket for deflecting effluent from said inlet into the basket.

9. A separator for immiscible liquids comprising: a tank having an inlet, an inlet chamber, a separation chamber and an outlet chamber, with the inlet feeding effluent into the inlet chamber, the inlet chamber bein in communication with the separation chamber throuh a first passage and the separation chamber being in communication with the outlet chamber through a second passage; an oil/grease outlet valve replaceably disposed in a valve housing coupled to said separation chamber, said valve having an interlocking connection to the valve housing.

A separator for immiscible liquids comprising: a tank having an inlet, an inlet chamber, a separation chamber and an outlet chamber, with the inlet feeding effluent into the inlet chamber, the inlet chamber being in communication with the separation chamber through a first passage and the separation chamber being in communication with the outlet chamber through a second passage, wherein effluent separates into a denser fluid and a less dense fluid in the separation chamber; an oil/ grease outlet valve disposed in said separation chamber, said valve comprising: 004664641v3 21 a sensor for sensing a height of said denser fluid in said separation chamber; a valve; an actuator for opening and closing said valve responsive to said sensor.

11. A separator of claim 10 wherein said valve is a ball valve.

12. A separator of claim 10 wherein said valve is a butterfly valve.

13. A separator of claim 10 wherein said valve is a gate valve.

14. A separator for immiscible liquids comprising: a tank having an inlet, an inlet chamber, a separation chamber and an outlet chamber, with the inlet feeding effluent into the inlet chamber, the inlet chamber being in communication with the separation chamber through a first passage and the separation chamber being in communication with the outlet chamber through a second passage, wherein effluent separates into a denser fluid and a less dense fluid in the separation chamber; a valve for releasing the less dense fluid from said separation chamber; and a heat blanket proximate to the bottom of the tank.

A separator of claim 14 and further comprising an induction heater coupled to an upper surface of said separation chamber.

16. A separator of claim 14 and further comprising an induction heater coupled to the valve.

17. A separator of claim 14 and further comprising a non-stick coating disposed on a bottom surface of the separation chamber.

18. A separator of claim 14 and further comprising an automatically- closing silt valve located proximate a lower surface of the tank for removing silt when open. 004664641v3 22

19. A separator for immiscible liquids comprising: a tank having an inlet, an inlet chamber, a separation chamber and an outlet chamber, with the inlet feeding effluent into the inlet chamber, the inlet chamber being in communication with the separation chamber through a first passage and the separation chamber being in communication with the outlet chamber through a second passage, wherein effluent separates into a denser fluid and a less dense fluid in the separation chamber; a valve for releasing the less dense fluid from said separation chamber; and flexible hollow tubing disposed about the bottom of the tank for creating a seal with the floor to prevent liquid from seeping below the tank.

A separator of claim 19 wherein said flexible hollow tubing comprises neoprene tubing.

21. A separator of claim 20 wherein the hollow tubing is mechanically affixed to the tank.

22. A separator of claim 19 wherein said tank comprises a lid portion and a body portion, and further comprising hollow tubing disposed on said lid portion and said body portion.

23. A separator of claim 21 wherein the hollow tubing is mechanically affixed to the lid and body portions.

24. A separator for immiscible liquids comprising: a tank for disposal in the ground, said tank having an inlet, an inlet chamber, a separation chamber and an outlet chamber, with the inlet feeding effluent with entrained silt into the inlet chamber, the inlet chamber being in communication with the separation chamber through a first passage and the separation chamber being in communication with the outlet chamber through a second passage, wherein effluent separates into a denser fluid and a less dense fluid in the separation chamber; wherein the separation chamber is defined within a housing by an inlet control plate, an outlet control plate and an upper control plate; 004664641v3 23 a valve disposed through the upper control plate for passing the less dense fluid above the upper control plate for removal; a heater disposed through the upper control plate; such that the heater, valve and less dense fluid for removal can be accessed through a lid on top of the housing.

A separator of claim 24 wherein the outlet chamber includes a weir over which both the denser fluid and the entrained silt flow.

26. A separator of claim 25 and further comprising: a first outlet for releasing the denser fluid; and a second outlet for releasing the silt.

27. A separator of claim 26 and further comprising a mesh filter proximate the first outlet for filtering silt from the denser fluid.

28. The separator of claim 26 wherein said outlet control plate has a channel for capturing silt.

29. The separator of claim 28 and further comprising an enlarged portion formed in said outlet control plate to create turbulence and additional suction to pull the entrained silt over the top of the weir.

A separator for immiscible liquids comprising: a tank for disposal in the ground, said tank having an inlet, an inlet chamber, a separation chamber and an outlet chamber, with the inlet feeding effluent with entrained silt into the inlet chamber, the inlet chamber being in communication with the separation chamber through a first passage and the separation chamber being in communication with the outlet chamber through a second passage, wherein effluent separates into a denser fluid and a less dense fluid in the separation chamber; a valve disposed in the separation chamber for passing the less dense fluid; a storage tank for storing the less dense fluid from the valve, said storage tank 004664641v3 24 having at least one access port for receiving waste fluids and for collection of fluids from the tank.

31. A separator for immiscible liquids substantially as described herein with reference to any one of figures 3 or 5a to 11.