Method and apparatus for cleaning and sanitizing a dispensing installation

Abstract

The present invention relates to a cleaning and sanitizing system for a dispensing installation that uses a single pump to pull in non-caustic, non-abrasive, and non-corrosive cleaning solution, which in turn draws in ambient air. The mixture of air and liquid is discharged into a cylindrical flow controller that discharges a flow of alternating liquid cylinders and air cylinders. The air cylinders eliminate the boundary layer and laminar sublayer, which in turn allows the liquid cylinders to apply a maximum shear force associated with the hydrodynamic entry region consistently cleaning the length of the beverage or product line with mechanical cleaning and sanitizing action, which is subsequently carried away within the liquid cylinder.

Claims

1. A system for cleaning and sanitizing a dispensing installation, comprising: a pump having a suction side and a discharge side; a liquid reservoir connected to the suction side of the pump; a cylindrical flow controller having an inlet port and a cylinder outlet port, wherein the inlet port is connected to the discharge side of the pump; a source of gas in communication with discharge side of the pump configured to provide a mixed phase of liquid and gas; and a product line connected to the cylinder outlet port, wherein the cylindrical flow controller is configured to produce an alternating flow of cylindrical gas and cylindrical liquid through the cylinder outlet port.

2. The system of claim 1 further comprising an air discharge line connected between the suction side of the pump and the source of gas.

3. The system of claim 2 further comprising a liquid discharge line connected between the suction side of the pump and the source of liquid.

4. The system of claim 3 further comprising the air discharge line connected to an air flow meter at an end opposite the pump, and the liquid air discharge line connected to a liquid flow meter at an end opposite the pump.

5. The system of claim 1 further comprising the pump having an orifice through the suction side that is configured to draw in the source of gas.

6. The system of claim 5 further comprising a liquid discharge line connected between the suction side of the pump and the source of liquid.

7. The system of claim 1 wherein the source of gas is ambient air.

8. The system of claim 1 further comprising the cylindrical flow controller having an elongated body that extends from a top to a bottom with a sidewall therebetween, which form an internal cavity.

9. The system of claim 8 further comprising the internal cavity having a head space positioned between the top of the elongated body and the cylinder outlet port.

10. The system of claim 8 further comprising the cylindrical flow controller having a pressurized liquid outlet adjacent the bottom of the elongated body and an inlet port between the cylinder outlet port and the pressurized liquid outlet.

11. The system of claim 10 further comprising a pressurized liquid line connected between the pressurized liquid outlet and a pressure relief valve.

12. The system of claim 1 further comprising a cylinder discharge line connected to the cylinder outlet port and configured to be connected to a product line of the dispensing installation.

13. The system of claim 1 further comprising a pump discharge line connected to the discharge side of the pump and the cylindrical form controller, wherein a diameter of the pump discharge line is less than a diameter of an internal cavity of the cylindrical form controller between a sidewall.

14. The system of claim 1 wherein the pump is the only pump.

15. The system of claim 1 wherein the liquid reservoir contains a cleaning solution having a pH between 9 and 11, and between 2% and 3% hydrogen peroxide by volume.

16. The system of claim 1 wherein the cylindrical gas of the alternating flow of cylindrical gas and cylindrical liquid is compressed and squeezed by the cylindrical liquid of the alternating flow of cylindrical gas and cylindrical liquid at opposing ends such that the cylindrical gas is pushed to an annular interior surface of a product line thereby removing the presence of a boundary layer and a laminar sublayer, and the cylindrical liquid have a hydrodynamic entry region that is maintained throughout circulation.

17. A cylindrical flow controller, comprising: an elongated body that extends from a top to a bottom with a sidewall therebetween, which forms an internal cavity; a head space positioned between the top of the elongated body and a cylinder outlet port in the sidewall; and a pressurized liquid outlet adjacent the bottom of the elongated body and an inlet port between the cylinder outlet port and the pressurized liquid outlet.

18. A method of cleaning and sanitizing a dispensing installation, comprising: providing a mixed phase flow of liquid and gas; circulating an alternating flow of cylindrical gas and cylindrical liquid from the mixed phase flow of liquid and gas; eliminating the presence of a boundary layer and a laminar sublayer in a product line of the cylindrical air; and mechanically cleaning an annular interior surface of the product line with the cylindrical liquid.

19. The method of claim 18 further comprising the step of the alternating flow cylindrical gas and cylindrical liquid compressing and squeezing opposing ends of the cylindrical gas with the cylindrical liquid, such that the cylindrical gas is pushed to the annular interior surface of the product line during the step of circulating the alternating flow of cylindrical gas and cylindrical liquid.

20. The method of claim 19 wherein the step of mechanically cleaning is accomplished by a hydrodynamic entry region that is maintained during the step of circulating the alternating flow of cylindrical gas and cylindrical liquid.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1. is a perspective view of a conventional beverage dispensing system;

(2) FIG. 2 is a top view of a beer stone formation;

(3) FIG. 3 is a schematic view of a system and method for cleaning and sanitizing a dispensing installation in a front end configuration;

(4) FIG. 4 is a schematic view of a system and method for cleaning and sanitizing a dispensing installation in a back end configuration;

(5) FIG. 5 is a schematic view of a system and method for cleaning and sanitizing a dispensing installation in a back and front end configuration;

(6) FIG. 6 is a schematic view of a system and method for cleaning and sanitizing a dispensing installation in a front end configuration;

(7) FIG. 7 is a schematic view of a system and method for cleaning and sanitizing a dispensing installation a back end configuration;

(8) FIG. 8 is a schematic view of a system and method for cleaning and sanitizing a dispensing installation in a back and front end configuration;

(9) FIG. 9A is a top perspective view of a system and method for cleaning and sanitizing dispensing installation;

(10) FIG. 9B is a front perspective view of a system and method for cleaning and sanitizing dispensing installation;

(11) FIG. 10A is a side view of a cylindrical flow controller;

(12) FIG. 10B is a cross-section view of a cylindrical flow controller during liquid cylinder formation;

(13) FIG. 10C is a cross-section view of a cylindrical flow controller during air cylinder formation;

(14) FIG. 11A is a cross-section view of mixed-phase flows flowing in a vertical direction;

(15) FIG. 11B is a cross-section view of mixed-phase flows flowing in a horizontal direction;

(16) FIG. 12A is a diagram of a liquid flow profile;

(17) FIG. 12B is a diagram of a liquid flow profile

(18) FIG. 12C is a diagram of a liquid flow profile and

(19) FIG. 13 are cross-section views of an alternating cylindrical flow.

DETAILED DESCRIPTION

(20) With reference to the Figures a cleaning and sanitizing system 10 and method for cleaning and sanitizing a beverage storage and dispensing installation 12 is provided, and as shown in the exemplary embodiment the beverage storage and dispensing installation 12 is used for the storage and dispensing of draft beer. Other storage and dispensing installations 12 are contemplated, however, including soda, wine, liquor, juice, and other beverages and condiments. In general, the system 10 is applicable for use in other fields where the product being transported is capable of depositing a biofilm 14 and other contaminants, such as industrial applications like chemical transport, agricultural applications like feed and dairy transport, and commercial applications like car washes.

(21) The typical beverage storage and dispensing installation 12 includes one or more beverage containers or reservoirs, such as a keg 16. The keg 16 is connected to a tavern head or keg coupler 18, which also has a gas line connector 20 and a product line connector 22.

(22) A gas container 24 is connected to the gas line connector 20 by a gas pressure line 25 that runs from the gas container 24 to a gas distribution center 26 and through to the gas line connector 20 by a counter gas pressure line 28. The gas container 24 provides pressurized gas, such as carbon dioxide (CO.sub.2), to the beverage to maintain pressure and carbonation.

(23) In some arrangements, a product line 30 extends from the product line connector 22 to a beer pump 32 that pumps the beer from the keg 16 to a tower head or dispensing station 34 that dispenses the beer through a spigot 36. In other arrangements, no beer pump 32 is present and the pressure from the gas container 24 is relied upon to transport the beer from the keg 16 to the tower head 34. The product line 30 length can vary based on the particular dispensing installation 12, but in large establishments, it is common for the length of the product line to be between 100 and 500 feet and have vertical portions that extend 6 to 20 feet to run underground or go over or through a wall 38 resulting in up and down vertical flows in addition to horizontal flows.

(24) To keep the beer stored in the product line 30 cold for consumption, a glycol cooling line 40 is run with the product line 30 that transports refrigerant pumped from a glycol cooling unit 42. It is common to bundle the glycol cooling line 40 and one more product lines 30 together in a line bundle 44 to simplify installation.

(25) The cleaning and sanitizing system 10 is positioned within a housing 46 that in some embodiments is mounted on a wheeled cart 48 (not shown) that allows the system 10 to be mobile for use at multiple sites or for storage. Alternatively, the system 10 is mounted within an establishment with or without a housing 46. In one embodiment the housing 46 has a height of approximately 10.0 inches, a length of approximately 12.0 to 13.0 inches, and a width of approximately 10.0 inches.

(26) The cleaning and sanitizing system 10 has a liquid inlet line 50 that extends between a first end 52A and a second end 52B and in some arrangements has a diameter of 0.375 inches, which is a common dimension in the draft beer field. The first end 52A of the liquid inlet line 50 is connected to and in communication with a reservoir 54 that is a bucket, canister, container, or any suitable device capable of holding a liquid. Adjacent the first end 52A is a filter 56 to remove particulate matter that could be present in the liquid or as the result of recirculation.

(27) The liquid inlet line 50 goes through an inlet port 58 on the housing and into an interior 60 of the housing 46. The second end 52B of the liquid inlet line 50 connects to a liquid flow meter 62 by a first or bottom port 64A. The liquid flow meter 62, which is positioned on an exterior surface 66 of the housing 46 to be readily viewable, and controls and monitors the rate of liquid flow with a needle valve 68 (not shown). In some arrangements of the present invention, the bottom port 64A of the liquid flow meter 62 is also positioned on an exterior surface 66 of the housing 46 that eliminates the need for the inlet port 58.

(28) A liquid discharge line 70 extends between a first end 72A and a second end 72B with the first end 72A connected to a second or top port 64B of the liquid flow meter 62. As seen in the exemplary embodiment, the second end 72B of the liquid discharge line 70 is connected to a first T-adapter 74.

(29) An air flow meter 76 having a first or bottom port 78A and a second or top port 78B. The air flow meter 76 is positioned on the exterior surface 66 of the housing 46 as well to be readily viewable, and controls and monitors the rate of air flow into the cleaning and sanitizing system 10. As shown in the exemplary embodiment, the bottom port 78A is not connected to a line of any kind, but instead is exposed to draw in atmospheric or ambient air from the surrounding environment without the need of a blower or air compressor as detailed further herein. In some arrangements, a filter 80 is positioned in or adjacent to the bottom port 78A to remove contaminants from the air, which is important because a high number of bacteria capable of spoiling beer have been found to come from contaminated air. In some arrangements of the present invention, the bottom port 78A is also positioned on an exterior surface 66 of the housing 46 to facilitate access to ambient air without the risk of creating a vacuum within the interior 60 of the housing 46.

(30) An air discharge line 82 that extends from a first end 84A to a second end 84B is connected to the top port 78B of the air flow meter 76. The second end 84B is connected to the first T-adapter 74 in substantially perpendicular alignment with the connection of the liquid discharge line 70. Between the first end 84A and second end 84B is a check valve 85 that prevents liquid from the liquid suction line 76 passing through the first T-adapter 74 and backing up into the air discharge line 82 to the air flow meter 76.

(31) A pump suction line 86 extends from a first end 88A and a second end 88B, with the first end 78A connected to the first T-adapter 74 opposite to and in substantially parallel alignment with the second end 72B of the liquid discharge line 70 and substantially perpendicular alignment with the second end 84B of the air discharge line 82. In some embodiments, the liquid discharge line 70, the air discharge line 82, and the pump suction line 86 are a single line that is forked.

(32) The second end 88B of the pump suction line 76 connects a suction side or suction port 90 of a pump 92. In some embodiments, a filter 94 is positioned in the suction port 90 or adjacent the suction port 90 in the second end 88B of the pump suction line 76 to prevent contaminants from entering the pump 92 and circulating and simultaneously limiting wear and extending the life of the pump 92.

(33) In the exemplary embodiment, the pump 92 is a positive displacement pump with a constant flow rate, but other pumps 92 are contemplated including variable flow pumps. The pump 92 is connected to a power source 96 such as an outlet or battery. The pump 92 is configured to receive a mixture of liquid and air on the suction side 90 and pressurize and compress the mixture to 60 PSIG, which is the maximum permitted by safety regulationabsent those safety regulations, configurations with higher PSIG are contemplated.

(34) A pump discharge line 98 that extends between a first end 100A and a second end 100B is connected to a discharge side or discharge port 102 of the pump 92 at the first end 100A. The second end 100B of the pump discharge line 98 is connected to a cylindrical flow controller 104.

(35) In some embodiments, the air discharge line 82 is connected to the pump discharge line 98 rather than the first T-adapter 74, such that ambient air is pulled by liquid discharged from the pump 92. In this way, the pump 92 does not act directly to draw in air, but rather air is drawn in by the liquid.

(36) The cylindrical flow controller 104 has a hollow elongated body 106 that has a sidewall 108 that extends from a top 110 and a bottom 112 with an internal cavity 114 therein. In the exemplary embodiment the elongated body 106 is cylindrical but other shapes are considered, but as shown, the elongated body has a width that is larger than the diameter of the pump discharge line 98. In one embodiment the length from top 110 to bottom 112 is approximately 9.5 inches and the internal cavity 114 has a 1.0 inch diameter between the sidewall 108.

(37) The elongated body 106 has a cylinder outlet port or top port 116, a pressurized liquid outlet or bottom port 118, and an inlet port or middle port 120 that is positioned between the top port 116 and the bottom port 118. To facilitate flow, the middle port 120 is on the opposite side of sidewall 108 of the elongated body 106 with respect to the top port 116. The top port 116 is set off below the top 110 such that there is a headspace 122 in the internal cavity 114 above the top port 116. The bottom port 118 is positioned at the bottom 112 and extends from the sidewall 108 as shown in the exemplary embodiment, but extends downwards from the bottom 112 in other embodiments.

(38) A pressurized liquid line 124 that extends from a first end 126A to a second end 126B with the first end 126A is connected to the bottom port 118 and the second end 126B is connected to a pressure relief valve 128 at an inlet port 130. The pressure relief valve 128 has a set point to open if the liquid pressure going through the pressurized liquid line 124 exceed 60 PSIG in accordance with safety regulations.

(39) Connected to an outlet port or bypass 132 of the pressure relief valve is a first end 134A of a pressure relief line 136. The second end 134B of the pressure relief line 136 goes through a pressure relief port 138 in the housing 46 and back into the liquid reservoir 54, or a waste container 140 in other embodiments. In an alternative arrangement, the second end 134B is connected to the liquid inlet line 50 or the liquid discharge line 70 to allow for a shorter line and faster recirculation. A filter 142 is inserted into the pressure relief line 136 to limit misting upon return to the liquid reservoir 54 and to remove any contaminants that could be present.

(40) A cylinder discharge line 144 that has a first end 146A and a second end 146B is connected to the top port 116 of the cylindrical form controller 104 at the first end 146A. Between the first end 146A and the second end 146B is a first portion 148 and a second portion 150 of the cylinder discharge line 144. Positioned between and connected to the first portion 148 and the section portion 150 is a second T-shaped adapter 152 such that the first portion 148 and second portion 150 are connected in substantially parallel alignment.

(41) Also connected to the second T-shaped adapter 152 is a pressure gauge line 154 that extends from a first end 156A to a second end 156B with the first end 156A connected to the second T-shaped adapter 152 in substantially perpendicular alignment with the cylinder discharge line 144. In other arrangements the cylinder discharge line 144 and the pressure gauge line 154 are a single line that is forked.

(42) The second end 1568 is connected to a pressure gauge 158 that displays the pressure of the cleaning and sanitizing system 10 after discharge from the pump 92, as well as the dispensing installation 12. The pressure gauge 158 is positioned on the exterior surface 66 of the housing 46 in some embodiments, and in other embodiments is within the interior 60 of the housing 46 and the current pressure is in communication to a remote device 160 (not shown), such as a cell phone or laptop either directly or through a network, including the Internet.

(43) The second end 146B of the cylinder discharge line 144 goes through an outlet port 162 in the housing 46 and is connected to the dispensing installation 12. The cleaning and sanitizing system 10 is configured to connect to the dispensing installation 12 in a variety of ways, including a front end configuration as exemplified in FIG. 3, a back end configuration as exemplified in FIG. 4, and in a back and front configuration as exemplified in FIG. 5.

(44) In the front end configuration, the second end 146B of the cylinder discharge line 144 is connected to the spigot 36 at the tower head 34, or to the tower head 34 directly. In this configuration, the product line 30 is connected to a first end 160A of a return line connector 163. A return line 164 that extends from a first end 166A to a second end 1668 connected to a second end 160B of the return line connector 163 with the first end 166A. The second end 166B of the return line 164 is connected to or in communication with the liquid reservoir 54 for recirculation, or in some embodiments, is connected to or in communication with the waste container 140. A filter 168 is positioned in the return line 164 near the second end 166B to demist the discharge back into the reservoir 54 or waste container 140 to limit the possibility of recontamination. In alternative arrangements, the product line 30 is connected to or in communication with the liquid reservoir 54 or waste container 140 without the presence of the return line connector 163 and the return line 164.

(45) In the back end configuration, the second end 146B of the cylinder discharge line 144 is connected to the keg coupler 18 in the same manner that the keg 16 connects to the keg coupler 18. As such, the keg 16 must be removed prior to connecting the cylinder discharge line 144 to the keg coupler 18. The first end 166B of the return line 164 is connected to the spigot 36, or directly to the tower head 34 in other arrangements. The return line 164 is similarly arranged as discussed with relation to the liquid reservoir 54 or waste container 140 detailed with relation to the front end configuration.

(46) In the back and front configuration, the second end 146B of the cylinder discharge line 144 is connected to the keg coupler 18 as disclosed previously. Attached to the spigot 36 or tower head 34 directly, is a jumper line 170 that extends from a first end 172A and the second end 172B with the first end 172A attached to a first spigot 36A or tower head 34A and the second end 172B attached to a second spigot 36B or tower head 34B. In this way, a back end configuration is completed but instead of running to the return line 164 directly, the jumper line 170 begins a front end configuration with the return line 164 connected as described with respect to the front end configuration. In this way two product lines 30 are cleaned in a single circulation.

(47) Like the liquid inlet line 50 and the liquid discharge line 70, the air discharge line 82, the pump suction line 86, the pump discharge line 98, the pressurized liquid line 124, the relief line 136, the cylinder discharge line 144, the pressure gauge line 154, and the return line 164, have a diameter of 0.375 inches in one embodiment to match the lines typically found in dispensing installations 12. In other embodiments, the diameter is 0.500 to match another industry standard, but can be other suitable sizes based on industry standards or a particular dispensing installation 12 configuration.

(48) In an alternative embodiment of the cleaning and sanitizing system 10, the pump 92 is a 5-stage diaphragm positive displacement pump with a built in bypass 132 capable of exceeding 60 PSIG but running at 50 PSIG while pumping seven gallons per minute. Other similar pumps 92 with the aspects detailed with relation to this embodiment are contemplated as well, such as a rotatory vein positive displacement pump 92 configured to regulate pressure by varying an air flow volume allowed into the pump 92, and should not be interpreted to be strictly limited to the 5-stage diaphragm positive displacement pump 92 with a built in bypass 132 An orifice 174 is positioned through the suction side 90 of the pump 92 to directly draw in ambient or atmospheric air during operation of the pump due to the flow of liquid in the pump 92. The use of this particular pump 92 reduces the weight of the pump 92 in comparison to other pumps 92 described herein by up approximately 20 pounds, reduces noise of operation and the amount of pulsation, which is nearly eliminated, and provides for a smaller physical footprint for storage, mounting, and transporting. Additionally, one or more of the following components need not be included due to the internal pressure regulation provided for in this arrangement: liquid flow meter 62, liquid discharge line 68, first T-adapter 74, air flow meter 76, air discharge line 82, check valve 85, the bottom port 118 of the cylindrical form controller 104, pressurized liquid line 124, pressure relief valve 128, pressure relief line 136, pressure relief port 136, second T-shaped adapter 152, pressure gauge line 154, and pressure gauge 158. In the described embodiment, the liquid inlet line 50 or the pump suction line 86 draws directly from the liquid reservoir to the suction side 90 of the pump. This embodiment and variations thereof, are also configured to connect to the dispensing installation 12 in a variety of ways, including a front end configuration as exemplified in FIG. 6, a back end configuration as exemplified in FIG. 7, and in a back and front configuration as exemplified in FIG. 8, while still providing for the same advantages and benefits over the state of the art as previously described.

(49) During operation, a cleaning solution 176 that includes water only, or is non-caustic, non-abrasive, and non-corrosive is prepared in the liquid reservoir 54 or the liquid reservoir 54 is prepared in advance and stored onsite or brought onsite during operation. Although caustic, abrasive, and corrosive cleaning solutions 176 could be used with the cleaning and sanitizing system 10, there is no need to do so.

(50) The cleaning and sanitizing system 10 is attached to the dispensing installation by way of the tower head 34 or the spigot 36 and the product line 30 is connected to the return line connector 163 in a front end configuration; or by way of the keg coupler 18, which can be onsite or brought during operation, and the return line 164 is connected to the tower head 34 or spigot 36 in a back end configuration; or in a back and front end configuration the jumper line 170 is connected between the first tower head 34A and the second tower head 34B, or the first spigot 36A and the second spigot 36B to combine the front end configuration and back end configuration thereby allowing for the cleaning and sanitization of multiple product lines 30. During operation, the kegs 16 are removed from their respective keg coupler 18

(51) Then, the pump 92 is connected to the power source 96 and powered on. The pump 92 pulls cleaning solution 176 from the liquid reservoir 54 to the suction port 90 of the pump 92, simultaneously consistently drawing in a source of air or gas, which is a quantity of ambient or atmospheric air 182 in the exemplary embodiment. In doing so, liquid is pulled through the liquid inlet line 50 and into the liquid flow meter 62, which regulates the liquid flow. The flow meter 62 is monitored and controlled onsite or by the remote device 160. The cleaning solution 176 is then discharged from the liquid flow meter 62 into the liquid discharge line 70, which is combined with the ambient air 182 at the first T-adapter 74. The ambient air 182 is added but does not add energy to the overall flow of the cleaning and sanitizing system 10. As the ambient air 182 is pulled in, it passes through the air flow meter 76 that monitors and controls the flow of air which can be controlled onsite or by the remote device 160.

(52) In some embodiments, the source of air or gas is not ambient air 182, but is gas or air that is injected in measured pressurized amounts, which expands until it equalizes to the pressure of the overall cleaning and sanitizing system 10. However, when this approach is taken, more control is necessary over the flow of gas or air to meet applicable safety guidelines, while adding unnecessary cost. Upon discharge, the flow is a mixture of gas and liquid for the first time as the air 182 and the cleaning solution 176 meet for the first time as a turbulent mixture inside the first T-shaped adapter 74 and are pulled into the pump 92 through the suction port 90.

(53) During this stage of operation, the air 182 and cleaning solution 176 are combined in substantially equal ratios of air to liquid necessary for proper operation. For instance, a 2:1 ratio or 1:1 ratio of air to liquid is contemplated. This is counter-intuitive to mist flow or droplet flow systems that require high air velocity at very high air to liquid ratios up to 6000:1 to achieve randomized instances of mechanical action.

(54) Once inside the pump 92, the mixture is pressurized up to 60 PSIG. The pressurized mixture is then discharged through the discharge port 102 of the pump 92 through the pump discharge line 98 and into the elongated body 106 of the cylindrical form controller 104 through the inlet port 120.

(55) In an alternative embodiment, the source of air or gas 182 is drawn in by cleaning solution 176 being discharged through the discharge line 98 that is connected after the discharge port 102. This is possible due to the velocity of the cleaning solution 176 that draws in ambient air 182 as the cleaning solution 176 passes through the T-shaped adapter 74. The use of the air flow meter 76 also for consistent addition from the source of air or gas 182.

(56) As seen in FIGS. 10A to 10C, the diameter of the elongated body 106 is greater than that of the pump discharge line 98, as well as the other lines described herein. In an exemplary embodiment, the diameter of the body is approximately 1.5 inches to 3.0 inches compared to the 0.375 inch diameter of the pump discharge line 98. Although the diameter of the elongated body 106 is greater, the diameter is not excessive larger to avoid excessive bulking that reduces cleaning and sanitizing efficiency, which will be apparent from the additional detail provided herein.

(57) Upon entry of the pressurized mixture into the cylindrical form control 104, the pressurized mixture has a reduction in velocity due to the change in diameter. This in turn provides for air bubbles 184 in the pressurized mixture to separate and rise from the liquid. The air bubbles 184 travel upwards due to buoyancy and gravity into the headspace 122 of the elongated body 106 to form a large air mass 186. For proper collection in the headspace 122, the elongated body 106 must be upright or substantially upright so that the top 110 of the elongated body 106 is above the bottom 112. Additionally, the slow down dampens or removes any pulsations from the pump 92 that could inhibit the cleaning and sanitizing process due to disruptions in uniformity and consistency. Pulsation is further dampened by the pressure exerted that compresses the large mass of air 186. Also, the cleaning solution 176 of the pressurized mixture separates into a large liquid mass 188 below the headspace 122 such that only liquid is adjacent the bottom 112 of the elongated body 106. The size of the cylindrical flow controller 104 provides the necessary time to all this separation to occur.

(58) As additional pressurized mixture is pumped into the elongated body 106, cylinders of liquid or cleaning solution 190 and cylinders of air or gas 192 are discharged out of the cylinder outlet 116 and into the cylinder discharge line 144. More particularly and as seen in FIGS. 10A to 10C, as the air 182 and the cleaning solution 176 separate, the liquid cylinder 190 is initially discharged due to the lack of ambient air in the headspace 122. As air 182 continues to accumulate in the headspace 122, the large air mass 186 becomes large enough that it extends to the cylinder outlet 116 and the cylinder of air 192 is discharged. This process is rapidly and consistently repeated as the pressurized mixture is constantly pumped into the cylindrical flow controller 104, which is positioned after the discharge port 102 of the pump 92. Without the headspace 122 above the cylinder outlet 116 a slug, plug, annular flow, or other mixed-phase flow would occur and not the alternating flow of liquid cylinders 190 and air cylinders 192.

(59) The alternating flow of liquid cylinders 190 and air cylinders 192 (alternatively referred to as a dynamic shear flow) flows in substantially the same manner regardless of orientation, including in a horizontal and vertical flow, including a upwards and downwards vertical flow. The flow is not disrupted at choke points or elbows that are typically found in dispensing installations 12 as product lines 30 go over, up, down, and through walls 38. Similarly, the flow is maintained even in curves and bends.

(60) Unlike air bubbles 184, the air cylinder 192 is compressed and squeezed by liquid cylinders 190 on opposite ends. This causes the air cylinder 192 to be pushed to an annular interior surface 194 of the product line 30. This means that air is in direct contact with the product line 30, including any restrictions 196 (not shown) that may be present. Necessarily, the air cylinder 192 eliminates the presence of any boundary layer or laminar sublayer that may be present.

(61) The liquid cylinder 190 is formed by the pump 92 exerting pressure from behind the cleaning solution 176, which is also subjected to the static pressure of the product line 30. Unlike mixed flows, the liquid cylinder 190 contacts the complete annular interior surface 194 of the product line 30, like the air cylinder 192, including restrictions 196 where present. Unlike a conventional liquid flow, as the liquid cylinder 190 follows the air cylinder 192 that has removed the boundary layer and laminar sublayer that would normally drag on the hydrodynamic entry region 198 causing the formation of the fully developed region, which includes the boundary layer and laminar sublayer. As a result, the hydrodynamic entry region 198 condition is continuously present in the liquid cylinder 190 throughout circulation regardless of direction, orientation, and changes in direction, orientation, or both.

(62) Further, by alternating liquid cylinders 190 and air cylinders 192, the liquid cylinder 190 is prevented from transitioning to the fully developed region 200 away from a lead surface 202 of the liquid cylinder 190 that is present in liquid flowswhich is why liquid flows are characterized with having a parabolic lead surface 202 as seen in FIG. 12C. Instead, the absence of the boundary layer or laminar sublayer allows for the hydrodynamic entry region to be maintained, which is apparent as seen in FIGS. 12 and 13 that show the lead surface 202 of the liquid cylinder 192 has a substantially flat profile associated with an irrotational core flow region 204 of the hydrodynamic entry region 198. Also, a rear surface 206 of the liquid cylinder 190 has a slight parabolic or turbulent shape demonstrating that minimal drag is present but still within the hydrodynamic entry region 198. However, the distance between liquid cylinders 190 and air cylinders 192 is such that there is insufficient length for the drag to cause formation of the fully developed region 200 as there is a constant push from another liquid cylinder 190 that maintains the desired flow of the liquid cylinder 190 and the integrity of the air cylinder 192.

(63) Because the boundary layer and laminar sublayer are absent, the interior surface 194 of the product line 30 is exposed to uninhibited contact from the hydrodynamic entry region, which applies a maximum shear force up to 100 fold higher than other methods are capable of producing during circulation. As a result, the liquid cylinder 190 mechanically acts on the complete interior surface 194 of the product line, essentially scouring the product line 30 upon contact. By controlling this profile of the liquid cylinder 190, maximum shear force is obtained without the need for high magnitudes of velocity set forth in mist flow and droplet flow systems because of the inherent shear force present at the hydrodynamic entry region.

(64) As contaminants, including beer stone and other biofilms 208, are cleaned from the interior surface 194, the liquid cylinder 190 entraps the contaminants and carries them out of the product line 30, thereby sanitizing the product line 30. Also, because there is no slippage present with the air cylinder 192, contaminants are not protected by the laminar sublayer from being carried out by the liquid cylinders 190, which stops recolonization.

(65) During operation, the alternating flow of liquid cylinders 190 and the air cylinders 192 are circulated through the dispensing installation 12 as detailed previously with the product line 30 being mechanically worked upon thousands of times during a cleaning cycle, which is only fifteen minutes in some implementations. As such, the flow is repeatable and reliable while applying maximum shear force constantly during the cleaning cycle.

(66) In the event that the pressure during operation exceeds the industry standard of 60 PSIG, the liquid mass 186 at the bottom 112 of the cylindrical form controller 104 is relieved through the pressure relief valve 128, which in some embodiments is then recirculated. The system pressure can be monitored by the pressure gauge 158 onsite, on the remote device 160, or by way of a pressure switch 161 (not shown).

(67) In some circumstances, the cleaning solution 176 is used in conjunction with the cleaning and sanitizing system 10. Unlike other cleaning solutions, the inventive cleaning solution 176 is non-corrosive, non-caustic, and non-abrasive. The cleaning solution 176 is prepared from a first container 178 (not shown) that contains hydrogen peroxide and a food-grade EDTA or sodium citratethe combination of which is stable for later dilution without the problem of having solids present. More particularly, the hydrogen peroxide has a concentration of 29% by volume. A second container 180 (not shown) contains an alkaline solution. The contents of the first container 178 and the second container 180 are combined in the liquid reservoir 54 and diluted so that the hydrogen peroxide has a concentration of 2% to 3% by volume and the overall pH is between 9 and 11. The use of the cleaning solution 176 is only possible due to the mechanical action of cleaning and sanitizing system 10, which would otherwise not be sufficiently abrasive, corrosive, or caustic. As such, rather than using multiple corrosive and harsh chemical solutions with strong acids or alkali that are potentially life-threatening during a multi-step cleaning process, the present invention provides for the cleaning solution 176, which although not ingestible can make contact with human tissue, and not cause burns, i.e., the cleaning solution 176 could be gargled much like gargling 2 to 3% hydrogen peroxide. The use of the cleaning solution 176, at most, extends the cleaning process to include a brief rinsing step.

(68) Therefore, a cleaning and sanitizing system 10 and associated method has been provided that provides mechanical cleaning action capable of removing contaminants, including beer stone, maintains the hydrodynamic entry region throughout circulation, as well as the related shear force in a continuous and persistent manner, that is not a mixed flow but an alternating flow system of liquid and air cylinders, provides a device to alter mixed flow into distinct cylinders of liquid and air, provides mechanical action in horizontal and vertical flows, regardless of flow action, including through transitions in a product line, that does not require forced air or gas, or energy from air or gas, that utilizes ambient or atmospheric air, that is a single-step process for cleaning, that does not use caustic solutions and other potentially life-threatening compositions, that works on a single product line from a front end or back end, or on multiple lines, that is quiet, safe, lightweight, potentially mobile, cost effective, and easy to use, that maintains beer quality and safety, and improves upon the art.

(69) From the above discussion and accompanying figures and claims it will be appreciated that the cleaning and sanitizing system 10 and method offers many advantages over the prior art. It will be appreciated further by those skilled in the art that various other modifications could be made to the device without parting from the spirit and scope of this inventionincluding implementation into other fields of endeavor, such as industrial applications like chemical transport, agricultural applications like feed transport, and commercial applications like car washes. All such modifications and changes fall within the scope of the claims and are intended to be covered thereby. It should be understood that the examples and embodiments described herein are for illustrative purposes only and that various modifications or changes in the light thereof will be suggested to persons skilled in the art and are to be included in the spirit and purview of this application.