Method and system for determining the end of a cip phase

Abstract

A method can involve directing a fluid through a fluid path including an industrial device to remove fouling from the industrial device during a phase of a clean-in-place (CIP) process (8). The method can include analyzing a turbidity of a fluid mass within the fluid path at a first time (22, 42) to provide a first measured turbidity of the fluid mass, and analyzing the turbidity of the fluid mass within the fluid path at a second time to provide a second measured turbidity of the fluid mass. In some cases, the fluid mass travels through the industrial device between the first time and the second time. The method can include determining an end of the phase of the CIP process based on the first measured turbidity and the second measured turbidity, and controlling the CIP process based on the determined end of the phase.

Description

Related applications

[0001] This application claims priority to U.S. Provisional Application No. 63 / 591,337, filed October 18, 2023, the entire contents of which are incorporated herein by reference. Technical Field

[0002] This disclosure relates to in-situ cleaning (CIP) technology, and more specifically to systems and techniques for controlling CIP processes. Background Technology

[0003] Clean in situ (CIP) is a cleaning technique suitable for removing dirt from internal components of industrial equipment, such as processing tanks, fluid lines, pumps, valves, heat exchangers, and other devices. CIP cleaning cleans the internal surfaces of these components typically without requiring disassembly of any of them for individual cleaning. In practice, the components are cleaned by passing a cleaning solution through them, for example, following the fluid path typically traveled by the fluid being processed on the equipment.

[0004] Due to their ease of use and effectiveness, CIP cleaning methods have been found to be widely applicable across many different industries, particularly those where hygiene and sterility are of paramount importance. Example industries using CIP cleaning methods include the dairy, beverage, brewing, processed food preparation, pharmaceutical, and cosmetic industries. In these and other industries, the inner surfaces of processing equipment accumulate dirt during operation. To help ensure the operational efficiency of processing equipment and prevent dirt buildup from contaminating the products produced on the equipment, the processing equipment is cleaned regularly using CIP methods.

[0005] The number of cleaning stages performed during a CIP cleaning method can vary depending on the specific process being performed. At least the cleaning solution must be passed through the treatment equipment before resuming normal operation. Any products subsequently passed through the equipment contaminated with cleaning agent residue can be discarded. More typically, a CIP cleaning method involves at least three stages. In the first stage, which may be called the pre-rinse or pre-wash stage, a fluid (such as fresh water) is passed through the treatment equipment to flush out contaminants in the system (e.g., residual products in the equipment, product buildup inside the equipment). In the second stage, which may be called the cleaning stage, a chemical solution is passed through the treatment equipment to clean and disinfect the equipment. Finally, in the third stage, a rinsing solution, such as fresh water, is passed through the treatment equipment to rinse away any residual cleaning solution from the equipment.

[0006] CIP processes are typically time-controlled, where each stage runs and lasts for a predetermined amount of time before stopping the stage and moving to the next stage or completing the entire CIP process. Summary of the Invention

[0007] Time-controlled CIP processes can operate and continue for predetermined periods, allowing one or more phases of the CIP process to run longer than necessary to accommodate worst-case scenarios and ensure that each phase has sufficient time to complete its intended task. However, this often results in more time being spent during one or more phases than is necessary. For example, if the object to be cleaned is sufficiently clean during a CIP phase, continuing the CIP phase may consume time and resources (e.g., chemicals used in the CIP phase, power to operate one or more system components such as pumps, valves, sensors, etc.) without providing the desired beneficial effect. Similarly, if the chemicals used during a CIP phase are consumed prematurely, the effectiveness of continuing the CIP fluid flow through the system is diminished. Therefore, in some cases, the equipment to be cleaned during a CIP phase may reach a steady state, where little or no further cleaning will be completed during the CIP phase, even if the phase continues.

[0008] Generally, aspects of this disclosure relate to systems and methods for determining the end of a phase of a CIP process using measurements associated with fluid flowing through a system. For example, some aspects of this disclosure relate to a method that includes guiding fluid through a fluid path comprising industrial equipment. The method may include analyzing the turbidity of a fluid mass within the fluid path at a first time to provide a first measurement of turbidity, and analyzing the turbidity of the fluid mass within the fluid path at a second time to provide a second measurement of turbidity, wherein the fluid mass travels through the industrial equipment to be cleaned between the first and second times. In some examples, this may include analyzing the turbidity at the first time using a first turbidity sensor upstream of the equipment, and analyzing the turbidity at the second time using a second turbidity sensor downstream of the equipment. In other examples, this may include analyzing the turbidity using a single sensor at multiple time points, wherein the fluid mass flows through the equipment after its turbidity has been analyzed by the single sensor, and then recirculates to the single sensor, in which its turbidity is analyzed at a second time after it has already flowed through the equipment.

[0009] Analyzing the turbidity of a fluid mass before and after it flows through the equipment to be cleaned can provide information about the dirt leaving the equipment. For example, an increase in the turbidity of the fluid mass leaving the equipment compared to the fluid mass entering the equipment indicates that dirt added from the equipment increased the turbidity of the fluid mass, and that the CIP phase has an impact on the dirt load on the equipment. On the other hand, if the turbidity of the fluid mass is approximately the same before and after flowing through the equipment, the equipment may not be adding a significant amount of dirt to the fluid to increase its turbidity. This could indicate that no substantial dirt removal has occurred, and the effectiveness of the CIP phase may have reached its end.

[0010] Therefore, in some examples, the method may include determining the end of a phase of the CIP process based on a first and a second measured turbidity. For example, in some cases, a sufficiently small difference between the first and second measured turbidities (e.g., below a predetermined threshold) may be used to determine the end of a phase of the CIP process.

[0011] Other uses for the first and second turbidity measurements are possible. For example, to reduce false negatives in determining the end of a phase of a CIP process, timing and / or counting conditions can be implemented. For instance, in some cases, if the difference between the determined first and second turbidity measurements is below a predetermined threshold, the count of such below-threshold differences (e.g., consecutive occurrences) can be incremented. In some such examples, if the run count of measured turbidity differences below a predetermined threshold (e.g., consecutive instances) meets a predetermined stripe threshold, the end of a phase of the CIP process is determined to have occurred. In some examples, if the measured turbidity difference is above a predetermined threshold, the run count is reset to zero (e.g., in a consecutive counting process). In other examples, if the measured turbidity difference is above a predetermined threshold, the run count is decremented by one and the analysis continues (e.g., in a cumulative summation process).

[0012] Other ways to determine the end of a phase of the CIP process may include, for example, fitting turbidity data over time to a turbidity model, or determining the rate of change of turbidity over time and comparing that rate of change to a threshold condition.

[0013] Generally, analyzing the turbidity of the fluid flowing through the equipment to be cleaned at multiple time points can be used to assess the equipment's impact on fluid turbidity and determine the end of a phase in the CIP process. In some examples, methods involve controlling the CIP process based on the determined end of a phase. For instance, the completion phase of the CIP process can be stopped, and a new phase of the CIP process can be started, or the entire CIP process can be completed.

[0014] Details of one or more examples are set forth in the accompanying drawings and description below. Other features, objects, and advantages will become apparent from the specification, drawings, and claims. Attached Figure Description

[0015] Figure 1 This is a diagram of an example Clean In-Situ (CIP) system.

[0016] Figure 2 It can be used Figure 1 A block diagram of an example sensor for a CIP system.

[0017] Figure 3A This is a high-level schematic diagram of a CIP system used for cleaning equipment.

[0018] Figure 3B This is a graph showing example turbidity information from the supply line sensor and the return line sensor.

[0019] Figure 3C This is a graph showing example turbidity information from the supply line sensor and the return line sensor, where the turbidity information from the supply line sensor is shifted over time.

[0020] Figure 3D It is an example calculated difference signal between turbidity information from the supply line sensor and turbidity information from the return line sensor.

[0021] Figure 3E This is an example of a continuous difference signal that shows the difference between consecutive points in the difference signal.

[0022] Figure 4 This is an example process flow diagram involving the use of difference analysis to determine the end of the CIP stage.

[0023] Figure 5 An example analysis of a continuous difference signal is shown to determine when the end of a phase of the CIP process has occurred.

[0024] Figure 6A Another advanced schematic diagram of a CIP system for cleaning equipment is shown.

[0025] Figure 6B An example graph showing the turbidity signal from a single turbidity sensor over time is shown. Detailed Implementation

[0026] This disclosure relates throughout to systems, apparatus, and techniques for cleaning industrial equipment using in-situ cleaning (CIP) methods. Initially, during the process, a pre-rinse fluid is passed under pressure through the industrial equipment to flush away dirt from the equipment during a pre-rinse phase. Following the pre-rinse phase, one or more cleaning phases may be performed, in which a cleaning fluid containing chemicals (e.g., detergents, acids, alkalis) is passed under pressure through the industrial equipment to facilitate the removal of solids from the equipment. Following the cleaning phases, a rinsing phase may be performed, in which a rinsing fluid is passed under pressure through the industrial equipment to facilitate the removal of residual chemicals from the equipment. Regardless of the phase, as used herein, the term dirt generally refers to one or more components intended to be cleaned from industrial equipment during a CIP process. Dirt may include residual product flushed from the equipment, accumulated product (e.g., baked product) in the equipment, and / or contaminants in the equipment, as well as other types of dirt.

[0027] Figure 1This is an illustration of an example CIP system 8, in which industrial equipment 10 is cleaned in situ. System 8 includes a pump 12 fluidly connected to a source of pre-rinse fluid 14 via a tank 15. Tank 15 is filled with pre-rinse fluid and provides a reservoir from which pump 12 can draw fluid. Pump 12 draws pre-rinse fluid 14 from its suction side, pressurizes the fluid inside the pump, and discharges the fluid into a fluid conduit 16 under the increased pressure. Fluid conduit 16 connects to a fluid inlet 18 of equipment 10 and delivers pressurized fluid from the pump to the equipment. Inside industrial equipment 10, pre-rinse fluid 14 can flush away dirt from the inner surfaces of the equipment, such that the pre-rinse fluid exiting the equipment's fluid outlet 20 contains dirt. Sensor 22 receives the dirt-containing pre-rinse fluid from fluid outlet 20 and analyzes the fluid, for example, to determine the concentration of dirt in the fluid. While in Figure 1 The diagram shows a sensor positioned to receive fluid from fluid outlet 20, but in some systems, one or more sensors (e.g., sensor 42 shown in dashed lines) may be positioned upstream of fluid inlet 18 of device 10, such that the sensor receives fluid, and the fluid then travels from the sensor to fluid inlet 18 of device 10. Various systems may include such sensors upstream, downstream, or both upstream and downstream of device 10.

[0028] In some examples, receiving fluid by sensors (e.g., 22, 42) may include physically receiving the fluid into the housing of the sensor. In other examples, receiving fluid may include receiving the fluid in the vicinity of the sensor, such that the sensor can obtain information about the fluid even if the fluid is not physically connected to the sensor. In some examples, sensor 22 and / or sensor 42 include a turbidity sensor configured to analyze the turbidity of the fluid. Fluid leaving industrial equipment 10 during the CIP process may be returned to tank 15 via conduit 21 for recirculation, or treated for discharge via conduit 23.

[0029] Figure 1 The CIP system 8 also includes a source 26 of concentrated cleaning and / or disinfecting chemicals fluidly connected to tank 15. During the cleaning phase of the CIP process following the pre-rinse phase, the concentrated chemicals may be dispensed into tank 15. In an example where the pre-rinse fluid 14 is water, a water source may also be fluidly connected to tank 15 to introduce water into the tank for use in producing a diluted chemical fluid from the concentrated chemicals 26. In operation, pump 12 can draw liquid cleaning fluid from tank 15, pressurize the fluid, and deliver the cleaning fluid through industrial equipment 10. Typically, the cleaning fluid containing cleaning agents and / or disinfectants is recirculated through industrial equipment 10 via conduit 21 via conduit 21 for a period of time or multiple recirculation cycles before being treated via conduit 23 for discharge.

[0030] The CIP system 8 also includes various valves (28, 29, 31, 32, 34) and fluid conduits that control fluid movement through the system. A controller 30 manages the overall operation of the CIP system 8. The controller 30 can be communicatively coupled to various components within the CIP system 8, for example via a wired or wireless connection, to send and receive electronic control signals and information between the controller 30 and the communicatively coupled components. For example, the controller 30 can electronically actuate valves (28, 29, 31, 32, 34) to open / close valves and control pump 12 to control fluid movement through the system. The controller 30 can also control one or more sensors (e.g., 22, 42) to analyze the fluid entering and / or leaving the device 10 and determine the level of fouling therein.

[0031] although Figure 1 A specific arrangement of a CIP system is shown, but it should be understood that this is merely an example. This disclosure is not limited to CIP systems with any particular configuration, much less... Figure 1 The CIP system 8 may have a specific configuration. In different examples, the CIP system 8 may not include tank 15, or may include multiple tanks, for example, one tank containing pre-rinse fluid and / or rinsing fluid, and a separate tank containing cleaning fluid. As another example, the CIP system 8 may include heat exchangers, heaters, and / or coolers to adjust the temperature of the fluids used during the CIP cleaning process. As will be understood by those skilled in the art, the CIP system 8 may include additional or different features.

[0032] Industrial equipment 10 can be flushed with pre-rinse fluid, cleaning fluid, and rinsing fluid at different times during the CIP cleaning process. The pre-rinse fluid can be a fluid used to flush out dirt within industrial equipment 10, helping to remove dirt residue and prepare the equipment for subsequent flushing with the cleaning fluid. The pre-rinse fluid is typically water (e.g., it may consist of or be substantially composed of water), but other suitable pre-rinse fluids can be used depending on the application. When the pre-rinse fluid is water, it can be supplied as fresh water from a pressurized mains line or can be reused at the location of industrial equipment 10 from a different process (e.g., condensate). In some examples, the pre-rinse fluid passes through industrial equipment 10 only once and is then discarded via conduit 23. In other examples, the pre-rinse fluid is recirculated through CIP system 8 via conduit 21, thus the fluid passes through tank 15, pump 12, and industrial equipment 10 multiple times. During each continuous pass through the industrial equipment, the pre-rinse fluid can remove more dirt from the industrial equipment. Recirculating the pre-rinse fluid through industrial equipment 10 can help save on the amount of fluid consumed during the pre-rinse process. Regardless of whether the pre-rinse fluid is recirculated through industrial equipment 10 or only passes through the equipment once, the fluid can be discarded at the end of the pre-rinse phase.

[0033] The cleaning fluid used to clean industrial equipment 10 is generated by concentrated chemical substance 26. Under the control of controller 30, a target amount of concentrated chemical substance 26, together with a target amount of water, is dispensed into tank 15 to produce a diluted cleaning fluid that is flushed through industrial equipment 10. Concentrated chemical substance 26 may contain detergents, disinfectants, or combinations of different reagents. For example, concentrated chemical substance 26 may be, but is not limited to, alkaline sources (e.g., sodium hydroxide, potassium hydroxide), triethanolamine, diethanolamine, monoethanolamine, sodium carbonate, morpholine, sodium metasilicate, potassium silicate, acid sources, inorganic acids (e.g., phosphoric acid, sulfuric acid), and organic acids (e.g., lactic acid, acetic acid, glycolic acid, citric acid, glutamic acid, glutamate, gluconic acid). Furthermore, although CIP system 8 is shown as having only a single concentrated chemical substance 26, in other examples, the system may include multiple concentrated chemicals used alone or in combination.

[0034] For example, the CIP system 8 may include a first concentrated chemical substance as an alkaline detergent and a second concentrated chemical substance as an acidic detergent. The controller 30 may initially combine the alkaline detergent with water in tank 15 and pass the alkaline detergent through industrial equipment 10. The alkaline detergent helps dissolve grease, protein, hard deposits, and other components. After the alkaline detergent wash, the equipment may or may not undergo an intermediate water rinse. Subsequently, the controller 30 may combine the acidic detergent with water in tank 15 and pass the acidic detergent through industrial equipment 10. The acidic detergent can remove inorganic deposits from the equipment and neutralize any remaining alkaline detergent on the equipment surfaces.

[0035] The rinsing fluid used in CIP system 8 is typically water, but other suitable fluids may also be used. After the cleaning phase of the CIP process, the rinsing fluid can pass through industrial equipment 10 to rinse away any remaining residual chemicals in the equipment. This prepares the industrial equipment for reprocessing products. In some examples, the rinsing fluid passes through industrial equipment 10 only once and is then discarded via conduit 23. In other examples, the rinsing fluid is recirculated multiple times through CIP system 8 via conduit 21 before being discarded.

[0036] To initiate a CIP cleaning process, controller 30 may receive a CIP request requesting the execution of a CIP cleaning procedure on industrial equipment 10. In response to this request, controller 30 may control CIP system 8 to initiate a series of cleaning stages on industrial equipment 10. For example, controller 30 may initiate a pre-rinse stage by opening valve 28 to fill tank 15 with water. Once the tank is properly filled, controller 30 may open valve 29 and actuate pump 12 to draw water from the tank and push pressurized water through industrial equipment 10. As the water contacts the inner surfaces of industrial equipment 10, it washes away dirt. In different examples, controller 30 may open either valve 31 or 32 to direct water back to tank 15 or a drain pipe. At the end of the pre-rinse stage, controller 30 may close valves 28, 29, 31, and / or 32 and stop pump 12.

[0037] Following the pre-rinse phase, controller 30 initiates the cleaning phase by opening valve 34 to dispense concentrated chemicals 26 into tank 15 and opening valve 28 to dispense water into the tank. Once the tank is properly filled with the cleaning fluid generated from the concentrated chemicals and water, controller 30 opens valve 29 and actuates pump 12 to draw cleaning fluid from the tank and push pressurized cleaning fluid through industrial equipment 10. As the cleaning fluid contacts the inner surfaces of industrial equipment 10, it cleans dirt, disinfects surfaces, etc. Typically, controller 30 opens valve 31 to guide the cleaning solution leaving industrial equipment 10 back into tank 15. Within tank 15, the returned cleaning fluid can be mixed with fresh concentrated chemicals 26 and / or water and then discharged via pump 12 for recirculation through industrial equipment 10. At the end of the cleaning phase, controller 30 opens valve 32 to discharge the cleaning fluid into a drain pipe, stops pump 12, and closes valves 28, 29, 31, 32, and / or 34.

[0038] Upon completion of the cleaning phase, controller 30 can initiate the rinsing phase by opening valve 28 to fill tank 15 with water. Once the tank is properly filled, controller 30 can open valve 29 and actuate pump 12 to draw water from the tank and push pressurized water through industrial equipment 10. As the water contacts the inner surface of industrial equipment 10, it flushes away cleaning fluid and any residual dirt. Controller 30 can recirculate the water back to tank 15 by opening valve 31 or drain the water to a drain pipe by opening valve 32. At the end of the rinsing phase, controller 30 can close valves 28, 29, 31, and / or 32 and stop pump 12. In this way, controller 30 can control the CIP system 8 to perform a series of cleaning phases to clean industrial equipment 10 without disassembling or removing the equipment from its normal operating position. However, it should be understood that the foregoing description of the CIP cleaning method is only an example, and different CIP cleaning methods can be used. For example, in some applications, the rinsing phase is omitted from the CIP cleaning method, for example, to prevent bacterial contamination of the equipment after the cleaning phase.

[0039] CIP system 8 includes sensors 22 and 42; however, it should be understood that different examples may include different numbers of sensors, such as a single sensor (e.g., sensor 22), two sensors (e.g., sensors 22 and 42), or more than two sensors. In the illustrated example, sensor 22 is configured to analyze the fluid leaving industrial equipment 10 in CIP system 8, and sensor 42 is configured to analyze the fluid entering industrial equipment 10 in CIP system 8. In some examples, sensor 22 is configured to analyze the turbidity of the fluid leaving equipment 10, and sensor 42 is configured to analyze the turbidity of the fluid entering equipment 10. In some examples, controller 30 is configured to receive information from sensor 22 regarding the turbidity of the fluid leaving equipment 10, and to receive information from sensor 42 regarding the turbidity of the fluid entering equipment 10.

[0040] A turbidity sensor may include a sensor configured to output turbidity information representing the fluid being analyzed. In some examples, the turbidity sensor is further configured to determine other information about the fluid being analyzed, such as fluorescence or other fluid properties. Example sensors configured to determine at least the turbidity of a fluid are described in U.S. Patents 9,618,450, 8,428,611, and 9,557,270, but other example sensors are also possible.

[0041] In some examples, controller 30 may control one or more aspects of the CIP cleaning method based on the determined turbidity of the fluid. For example, in some examples, controller 30 may use information from one or more turbidity sensors to determine when a phase of the CIP process is completed, such as when no remaining dirt remains to be removed from the equipment being cleaned and / or when the chemicals used to perform the CIP process have been consumed, thereby diminishing the effectiveness of continuing the current phase of the process.

[0042] Sensors 22 and / or 42 can be implemented in a variety of different ways in the CIP system 8. Figure 1 In the example shown, sensor 22 is positioned in a straight line with the fluid conduit exiting industrial equipment 10 to determine the turbidity of the fluid flowing through the conduit. In other examples, a sample line may be connected to a main conduit exiting industrial equipment 10. In such examples, the sample line can fluidly connect sensor 22 to the main fluid conduit. As fluid moves through the main fluid conduit, a portion of the fluid may enter the sample line and pass through the adjacent sensor, allowing sensor 22 to determine the turbidity of the fluid flowing through the main fluid conduit. When implemented to continuously receive fluid, sensor 22 can be characterized as an in-line sensor. In other examples, sensor 22 can be implemented as an offline sensor, which receives fluid intermittently, for example, by manually filling the sensor with fluid. Similar variations can also be applied to sensor 42.

[0043] In one example, sensor 22 receives fluid exiting industrial equipment 10 via fluid outlet 20 during the alkaline washing phase of the CIP process. Sensor 22 detects the turbidity of the fluid, which indicates the level of contamination in the fluid leaving the equipment, and thereby generates a sensor output representing the turbidity. Controller 30 receives the turbidity information from sensor 22 and determines the measured turbidity of the fluid based on the received turbidity information. In some examples, controller 30 receives turbidity information from sensor 22 multiple times. From this information, controller 30 can determine the end of a CIP phase, such as the end of the alkaline washing phase. In some examples, controller 30 is a local controller configured to process the information received from the sensor to determine the end of the CIP phase. In some cases, controller 30 may include a local controller configured to communicate with a remote location, such as a cloud-based computing platform, for determining the end of the CIP phase.

[0044] A CIP request received by controller 30 to initiate a CIP process can be entered via a user interface or stored in memory associated with the controller. For example, CIP system 8 may include a user interface presenting a variety of pre-programmed CIP cleaning options (e.g., a menu of pre-programmed CIP cleaning processes) from which the user can select. As another example, the user interface may allow the user to input parameters for generating customized CIP cleaning phases. Parameters specified by the user via the user interface may relate to the intensity of the cleaning process performed by the CIP system. For example, the user may select the flow rate at which pump 12 pumps fluid through industrial equipment 10 at each stage of the CIP process, the duration (e.g., time or fluid volume) during each stage of the process, the concentration of chemicals used in the cleaning fluid, whether and when the fluid is recirculated or discharged to a drain during the process, and / or the temperature of the fluid pumped through the equipment.

[0045] In some examples, the CIP system 8 can be programmed to automatically initiate the CIP cleaning process at predetermined times or at periodic intervals. Based on information stored in the memory associated with the controller 30, the controller can control various valves and pumps in the system to perform the CIP cleaning process.

[0046] CIP system 8 is configured to clean industrial equipment 10. Industrial equipment 10 in Figure 1 The industrial device 10 is conceptually shown as a single module with an inlet 18 and an outlet 20. The depiction of the industrial device 10 as a single module is for illustrative and discussion purposes only. It is envisioned that the industrial device 10 may comprise one or more individual industrial devices (e.g., two, three, four, or more), each including an inlet for fluid entry and an outlet for fluid exit. Multiple industrial devices may be connected in series to provide a fluid loop through which fluid travels from one industrial device to another. In some examples, the industrial device 10 defines multiple fluid loops, each with multiple industrial devices connected in series. In such examples, the CIP system 8 may have separate pumps and / or fluid conduits that fluidly connect the different fluid loops to the CIP system 8. Additionally, the CIP system 8 may have fluid / valve manifolds to individually connect each of the different fluid loops to the CIP system.

[0047] Examples of individual components of the industrial equipment 10 include evaporators, separators, fermenters, aging tanks, liquid storage tanks, malt slurry containers, mixers, pressurized and non-pressurized reactors, dryers, heat exchangers (such as HTST heat exchangers (e.g., for pasteurization of milk, juice, or other products)), and homogenizers, but other examples are also possible. The industrial equipment 10 may also include flow devices that provide mechanisms for transporting and / or guiding materials processed, stored, and / or produced during normal operation of the equipment. For example, flow devices may include delivery lines, valves, valve assemblies, valve manifolds, flow restrictors, conveying lines (e.g., pipes, conduits), orifices, and pumps.

[0048] CIP systems 8 are typically located within industrial facilities that process products. These industrial facilities can provide for the processing, storage, and / or production of a variety of end products. Exemplary industries that may use CIP systems 8 include the food industry, beverage industry, pharmaceutical industry, chemical industry, and water purification industry. In the case of the food and beverage industry, the products processed by industrial equipment 10 (and thus the sources of contamination remaining in the equipment) may include, but are not limited to, dairy products such as whole milk and skim milk, condensed milk, whey and whey derivatives, buttermilk, proteins, lactose solutions and lactic acid; protein solutions such as soy whey, nutritional yeast and feed yeast, and whole eggs; fruit juices such as orange juice and other citrus juices, apple juice and other apple juices, cranberry juice, coconut milk and tropical juices; vegetable juices such as tomato juice, beetroot juice, carrot juice and grass juice; starch products such as glucose, dextrose, fructose, isomers, maltose, starch syrup and dextrin; sugars such as liquid sugar, refined white sugar, sweetened water and insulin; extracts such as coffee and tea extracts, hop extracts, malt extracts, yeast extracts, pectin, and meat and bone extracts; hydrolysates such as whey hydrolysates, soup seasonings, milk hydrolysates, protein hydrolysates; beer such as dealcoholized beer and wort; baby food, egg whites, soybean oil and fermented wines.

[0049] The composition of the contaminants cleaned from industrial equipment 10 will vary depending on the application of the industrial equipment. Generally, the contaminants will include some or all of the products recently treated on industrial equipment 10 prior to initiating the CIP cleaning process. When industrial equipment 10 provides heated surfaces (e.g., heat exchangers, evaporators), the contaminants may include thermal degradation renders of products recently treated on the industrial equipment. Example contaminants may include carbohydrates, proteinaceous substances, edible oils, cellulose, monosaccharides, disaccharides, oligosaccharides, starch, gums, proteins, fats, and oils. In some examples, the contaminants include polycyclic compounds and / or benzene molecules having one or more substituent electron-donating groups, such as -OH, -NH2, and -OCH3, which may exhibit fluorescent properties.

[0050] Pump 12 in CIP system 8 can be any suitable fluid pressurization device, such as a direct lift pump, positive displacement pump, velocity pump, buoyancy pump, and / or gravity pump, or any combination thereof. Generally, the components described as valves (28, 29, 31, 32, 34) can be any device that regulates fluid flow by opening or closing fluid communication through a fluid conduit. In various examples, the valve can be a diaphragm valve, ball valve, check valve, gate valve, spool valve, piston valve, rotary valve, shuttle valve, and / or combinations thereof. Each valve may include an actuator, such as a pneumatic actuator, electric actuator, hydraulic actuator, etc. For example, each valve may include a solenoid, piezoelectric element, or similar feature to convert electrical energy received from controller 30 into mechanical energy to mechanically open and close the valve. Each valve may include a limit switch, proximity sensor, or other electromechanical device to provide confirmation that the valve is in the open or closed position, the signal of which is transmitted back to controller 30.

[0051] In CIP system 8, fluid conduits and fluid lines can be conduits or segments that allow fluid to be transported from one location in the system to another. The material used to manufacture the conduits should be chemically compatible with the liquid to be transported, and in various examples, can be steel, stainless steel, or polymers (e.g., polypropylene, polyethylene).

[0052] exist Figure 1 In the example, sensor 22 analyzes the fluid passing through industrial equipment 10, for example, to determine the turbidity of the fluid. Figure 2 This is a block diagram illustrating an example of sensor 200, which can be used to analyze fluid from CIP system 8 to determine information representing the turbidity of the fluid being analyzed. Sensor 200 can be used as sensor 22 in CIP system 8.

[0053] See Figure 2 The sensor 200 includes a controller 220, one or more optical transmitters 222 (referred to herein as "optical transmitter 222"), and one or more optical detectors 224 (referred to herein as "optical detector 224"). The controller 220 (which can be connected to...) Figure 1 The controller 30 (identical to the one in the original text) includes a processor 226 and a memory 228. In operation, the optical emitter 222 directs light into the fluid flowing through the fluid conduit 230 (e.g., a pre-rinse fluid containing dirt), and the optical detector 224 detects the light scattered by the fluid. In some cases, the amount of light scattered by the fluid can represent the turbidity of the fluid. For example, when light is directed to exit industrial equipment 10 (… Figure 1When the light is in a pre-rinse fluid that also contains dirt, the dirt particles in the fluid can scatter the light emitted from the optical emitter 222, so that the scattered light is received at the optical detector 224. In some examples, the optical emitter 222 directs light of one wavelength into the fluid flowing through the fluid conduit 230, and the same wavelength of light is detected by the optical detector 224.

[0054] In some examples, memory 228 stores software and data used or generated by controller 220. For example, memory 228 may store data used by controller 220 to determine or otherwise analyze the turbidity of a fluid from one or more sensors within the system. In some examples, memory 228 stores data in the form of equations or lookup tables that correlate signals output by one or more sensors with the turbidity of the fluid.

[0055] Processor 226 runs software stored in memory 228 to perform functions attributable to sensor 200 and controller 220 in this disclosure. Components described as processors within controller 220, controller 30, or any other device described in this disclosure may each include one or more processors individually or in any suitable combination, such as one or more microprocessors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), programmable logic circuit systems, etc.

[0056] Optical emitter 222 includes at least one optical emitter that emits light energy into a fluid present within fluid conduit 230. In some examples, optical emitter 222 emits light energy within a certain wavelength range. In other examples, optical emitter 222 emits light energy at one or more discrete wavelengths. For example, optical emitter 222 may emit two, three, four, or more discrete wavelengths.

[0057] In various examples, optical emitter 222 emits light within the ultraviolet (UV), visible, and / or infrared (IR) spectra. The specific wavelength of light emitted by optical emitter 222 can be, for example, determined based on the intended emission from industrial device 10 (…). Figure 1 The frequency of light emission varies depending on the type of dirt being washed. In some examples, the optical emitter 222 emits light at frequencies less than 350 nanometers (nm), such as less than 330 nm or less than 300 nm. For example, the optical emitter 222 may emit light in the frequency range of approximately 275 nm to approximately 335 nm. However, the aforementioned wavelengths are merely examples, and other wavelengths of light may be used.

[0058] The optical emitter 222 can be implemented within the sensor 200 in various different ways. The optical emitter 222 can include one or more light sources to excite molecules within the fluid. Example light sources include light-emitting diodes (LEDs), lasers, and lamps. In some examples, the optical emitter 222 includes a filter for filtering the light emitted by the light source. The filter can be positioned between the light source and the fluid and is selected to allow light within a specific wavelength range to pass through. In some additional examples, the optical emitter includes a collimator, such as a collimating lens, a cover, or a reflector, positioned near the light source to collimate the light emitted from the light source. The collimator can reduce the divergence of the light emitted from the light source, thereby reducing optical noise.

[0059] Sensor 200 also includes an optical detector 224. Optical detector 224 includes at least one optical detector that detects light scattered by the fluid within the fluid conduit 230. Although in Figure 2 The optical detector 224 is shown on the same side of the fluid conduit 230 as the optical emitter 222, but in some examples, the optical detector 224 is located on a different side of the fluid conduit 230 from the optical emitter 222. For example, the optical detector 224 may be located on a side of the fluid conduit 230 that is offset by approximately 90 degrees relative to the optical emitter 222.

[0060] In operation, the amount of light energy detected by optical detector 224 can depend on the turbidity of the fluid within fluid conduit 230. If the fluid conduit contains a fluid solution with certain properties (e.g., a certain concentration of dirt), optical detector 224 can detect a specific level of light energy scattered by the fluid. However, if the fluid solution has different properties (e.g., different concentrations of dirt), optical detector 224 can detect different levels of light energy scattered by the fluid. For example, if fluid conduit 230 is filled with a pre-rinse fluid having a first concentration of dirt, optical detector 224 can detect a first order of magnitude of scattered radiation. However, if fluid conduit is filled with a pre-rinse fluid having a second concentration of dirt greater than the first concentration, optical detector 224 can detect radiation greater than the first value.

[0061] The optical detector 224 can also be implemented within the sensor 200 in various different ways. The optical detector 224 may include one or more photodetectors, such as photodiodes or photomultipliers, to convert optical signals into electrical signals. In some examples, the optical detector 224 includes a lens positioned between the fluid and the photodetector for focusing and / or shaping the light energy received from the fluid.

[0062] The controller 220 controls the operation of the optical transmitter 222 and receives signals relating to the amount of light detected by the optical detector 224. In some examples, the controller 220 further processes the signals, for example, to determine the turbidity of the fluid passing through the fluid conduit 230.

[0063] In one example, controller 220 controls optical emitter 222 to direct radiation into a fluid containing dirt, and further controls optical detector 224 to detect light scattered by the dirt in the fluid. Controller 220 then processes the light detection information to determine the turbidity of the dirt in the fluid.

[0064] although Figure 2 An example turbidity sensor based on the scattering of light emitted toward a fluid is shown; however, it should be understood that other turbidity sensors are also possible. In various examples, the turbidity sensor may include a light emitter and a light sensor on the same or opposite sides of the flow path. In some cases, the light emitter and sensor may be oriented relative to each other at an angle, such as 90 degrees or other angles. Some sensors utilize multiple wavelengths of light and / or multiple sensors at different locations (e.g., different angles) to simultaneously capture different light signals from the fluid.

[0065] In some cases, the turbidity of the fluid flowing through CIP system 8 varies during the CIP process phases, for example, as contaminants are removed from the industrial equipment and carried through the fluid flowing through it. Typically, during operation, one or more aspects of the industrial equipment and / or the fluid flowing through the CIP system evolve as the CIP phase progresses over time. For example, when a CIP phase operates to remove contaminants from the industrial equipment, the contaminant level within the industrial equipment may decrease over time; however, the contaminant level in the fluid increases due to the removal of contaminants from the industrial equipment. In various example implementations, a point in time occurs where the CIP phase no longer effectively affects the industrial equipment, for example, if the industrial equipment has been cleaned to remove any contaminants intended to be removed by the CIP phase and / or if chemicals present in the fluid flowing through the CIP system have been consumed, reducing the fluid's effectiveness in advancing the CIP phase. Therefore, although aspects of the industrial equipment and / or the fluid flowing through the CIP system evolve over time, these aspects can reach a steady state, such as once all contaminants have been removed or fluid chemicals have been consumed.

[0066] Detecting the endpoint by observing such steady-state states of CIP process phases can be advantageous. When a CIP phase reaches steady-state conditions, such as when the chemicals in the CIP fluid have been consumed or no target contaminants have been removed from the industrial equipment, spending additional time to continue allowing the CIP fluid to flow through the industrial equipment can consume time and operational resources (e.g., power for running pumps, valves, etc.) while contributing little or no to the system. Therefore, in some examples, the system can be configured to determine that the end of a CIP process phase has occurred and that the CIP process can proceed to the next phase. This may be superior to other systems, such as time-based systems, which run the CIP phase for a predetermined amount of time regardless of whether the fluid flow continues to have any effect.

[0067] However, during stages of a CIP process designed to remove contaminants, for example, from industrial equipment, turbidity measurements may not reflect a steady change in the overall contaminant composition of the fluid flowing through the CIP system. For instance, contaminants are not necessarily removed uniformly from industrial equipment. Furthermore, contaminants removed from industrial equipment may continue to flow through the CIP system, thus contributing to subsequent turbidity measurements.

[0068] Therefore, in some examples, when analyzing the turbidity of fluid flowing through a CIP system, the controller is configured to analyze the turbidity of a consistent fluid mass. For example, in some examples, the turbidity sensor outputs information representing the turbidity of a certain volume of fluid approaching and / or flowing through the turbidity sensor. A fluid mass may include the volume of fluid analyzed by the turbidity sensor at a given time or over a given duration. Fluid masses can be tracked by the CIP system. For example, for fluid flowing through the system at a known flow rate, the location of a given fluid mass can be determined relative to a reference time and location. For example, in an example CIP recirculation system for recirculated fluid, if the fluid path length is X meters and the fluid flow rate is Y meters per second, the fluid mass will complete one cycle in the recirculation system within X / Y seconds. Similarly, the fluid mass will travel between two known points separated by Z meters in the fluid path within X / Z seconds.

[0069] Therefore, in some examples, the turbidity of the fluid mass over time can be analyzed such that each such turbidity measurement reflects the turbidity of the same fluid. For example, in some examples, the controller can be configured to determine the flow rate of the fluid through the CIP system, for example, via measurement (such as by a flow meter) or by predetermined pump speed settings and / or specifications.

[0070] refer to Figure 1The controller 30 can be configured to guide fluid through the fluid path of the CIP system 8 during the CIP phase. The controller can analyze the turbidity of the fluid mass within the fluid path at a first time to provide a first measurement of the fluid mass's turbidity, and analyze the turbidity of the fluid mass at a second time to provide a second measurement of the fluid mass's turbidity. In some such examples, the controller 30 receives information about the turbidity of the same or nearly identical fluid at both time points. In some examples, the fluid mass flows through the industrial device 10 between the first and second times, such that dirt released from the industrial device 10 between the first and second times contributes to the turbidity of the fluid mass.

[0071] In some examples, analyzing the turbidity of the fluid mass at both the first and second time points can be performed using a single turbidity sensor. For example, see reference... Figure 1 Sensor 22 can provide turbidity information to controller 30 representing the turbidity of the fluid mass at a first time point, and can further provide turbidity information representing the turbidity of the fluid mass at a second time point after the fluid mass completes its recirculation loop and travels through industrial equipment 10. In such an example, the time difference between the first and second times point can be the amount of time it takes for the fluid mass to complete its recirculation loop in the fluid path.

[0072] In other examples, analyzing the turbidity of the fluid mass at both the first and second time points can be performed using multiple turbidity sensors. For example, refer to... Figure 1 Sensor 42 can provide turbidity information to controller 30 representing the turbidity of the fluid mass at a first time point, and sensor 22 can provide turbidity information to controller 30 representing the turbidity of the fluid mass at a second time point. In some such examples, the time difference between the first and second times is the time it takes for the fluid mass to flow from sensor 42 to sensor 22, during which time the fluid mass flows through industrial equipment 10.

[0073] As described above, in some cases, when the system reaches equilibrium, it can indicate that the CIP phase has no further impact on the industrial equipment, such as because contaminants in the equipment are being depleted and / or chemicals in the fluid are being consumed. In some examples, such equilibrium can be detected by industrial equipment that has little or no impact on the turbidity of the fluid flowing through it. In some examples, the controller is configured to determine the end of a phase of the CIP process based on a first and a second measured turbidity. For example, in some examples, when the first and second measured turbidities bring the CIP phase to equilibrium and no new contaminants are added to the system from the industrial equipment. The controller can be configured to determine, for example, via local processing and / or by utilizing cloud-based computing, that the end of the CIP phase has occurred. For example, in some examples, the controller includes a local controller configured to transmit data to a cloud-based computing platform where the data can be processed to determine the end of the CIP phase. The cloud-based computing platform can then communicate the completion of the CIP phase to the local controller.

[0074] In some examples, the controller may control the CIP process at the end of the process (e.g., via local data processing or using a cloud-based computing platform). For example, the controller may control one or more valves to proceed to a subsequent stage of the entire CIP process or to terminate the CIP process. In some examples, the controller may discharge fluid, such as contaminated CIP fluid from industrial equipment, from a fluid path by controlling a valve (e.g., 32) to direct fluid to a drain (e.g., via conduit 23). Alternatively, the controller may add one or more additional fluids to the fluid path to perform one or more subsequent CIP stages.

[0075] In some examples, multiple sensors are positioned on either side of the industrial equipment to be cleaned (e.g., Figure 1 Sensors 22 and 42 in the image can be used to assess progress in the CIP phase. Figures 3A to 3E Example systems and data that can be used to monitor the progress of the CIP phase are shown. Figure 3A A high-level schematic diagram of a CIP system for cleaning equipment is shown. As shown, CIP system components 308 (e.g., one or more valves, conduits, pumps, etc.) are in fluid communication with industrial equipment 310 to be cleaned. A supply line sensor 342 is positioned and configured to provide turbidity information about the fluid entering the industrial equipment 310, and a return line sensor 322 is positioned and configured to provide turbidity information about the fluid leaving the industrial equipment 310. In some examples, the configuration of the supply line sensor 342, the industrial equipment 310, and the return line sensor can be used as... Figure 1Sensor 42, device 10, and sensor 22 are illustrated in the system. During an example operation of the CIP phase, CIP fluid is supplied to the industrial equipment 310 to be cleaned. The fluid encounters supply line sensor 342 before reaching equipment 310 and return line sensor 322 after leaving equipment 310. In some examples, the fluid is recirculated through the CIP system, such as via one or more pumps that are part of CIP system component 308. The controller can receive information from the supply line sensor 342 and the return line sensor 322 to analyze the turbidity at each location during the CIP phase.

[0076] Figure 3B A graph illustrating example turbidity information received by the controller from supply line sensor 342 and return line sensor 322 is shown. This graph includes supply line sensor data 352 and return line sensor data. In the illustrated example, the CIP phase (e.g., alkaline washing phase) begins at time t1. At time t2, supply line sensor data 352 shows a small peak in turbidity, and at time t3, return line sensor data shows a larger peak in turbidity.

[0077] In some examples, the time difference between t2 and t3 is the amount of time that the circulating fluid in the CIP system takes to travel between the supply line sensor 342 and the return line sensor. In some such examples, the turbidity measured at the supply line sensor 342 at time t2 represents the turbidity of the same fluid mass as the turbidity measured at the return line sensor 322 at time t3. Similarly, the turbidity measured at the supply line sensor 342 at time t5 represents the turbidity of the same fluid mass as the turbidity measured at the return line sensor 322 at time t6.

[0078] Figure 3C A graph showing example turbidity information received by the controller from supply line sensor 342 and return line sensor 322 is shown, where the turbidity information from supply line sensor 342 is offset by the time difference between t2 and t3. Figure 3C The example graph shows the shifted supply line sensor data 362 and return line sensor data 350. Because the supply line sensor data 362 is shifted by the amount of time the fluid mass takes to travel between the supply line sensor 342 and the return line sensor 322, Figure 3C The graph shows turbidity information for the same fluid mass at a given time point at both the supply line sensor 342 (based on shifted supply line sensor data 362) and the return line sensor 322 (based on return line sensor data 350). Therefore, in Figure 3CIn the graph, at a given time point, the difference between the shifted supply line sensor data 362 and the return line sensor data 350 represents the difference in turbidity of a given fluid mass at supply line sensor 342 and return line sensor 322. For example, arrow 360 represents the difference between the turbidity of a given fluid mass measured by supply line sensor 342 at time t2 and the turbidity of a given fluid mass measured by return line sensor 322 at time t3.

[0079] In some examples, the controller is configured to receive turbidity information from the supply line sensor 342 and the return line sensor 322, and to time-shift at least one of the data sets by the amount of time a fluid mass takes to travel between the supply line sensor 342 and the return line sensor 322. The controller may be configured to calculate a turbidity difference signal based on the difference between a continuous turbidity signal from the return line sensor 322 and a time-shifted continuous turbidity signal from the supply line sensor 342. For example, in some examples, the controller may determine the turbidity difference signal based on the difference between the return line sensor data 350 and the shifted supply line sensor data 362, such as... Figure 3C As shown.

[0080] Figure 3D The example calculated difference signal 364 is shown. As described, difference signal 364 can represent the difference between the return line sensor data 350 and the shifted supply line sensor data 362, such as... Figure 3C As shown. Figure 3D A smoothed difference signal 366 is also shown. In some examples, the smoothed difference signal may be calculated based on a rolling average or rolling median of data from the original difference signal (e.g., via a controller). Other smoothing processes, such as Kalman filters, may be used to provide the smoothed difference signal. In various examples, the smoothed difference signal includes the average or median of a predetermined number of previous original differences. In some examples, data between 30 and 120 seconds is used to calculate the smoothed difference signal, and in some examples, approximately 60 seconds of data may be used. In some examples, the smoothed difference signal includes one data point for each time interval used to calculate the smoothed difference signal value. For example, in some examples, if the rolling median is calculated over a one-minute time interval, the smoothed difference signal may include one data point per minute. In some examples, the smoothed difference signal includes more than one data point for each time interval used to calculate the smoothed difference signal value. For example, in an example implementation, each data point of the smoothed difference signal is calculated using 120 previous data points (e.g., more than 120 seconds of data), and the smoothed difference signal includes one such data point every 60 seconds.

[0081] like Figure 3DAs shown in the examples, in some examples, the difference signal may include a continuous signal, such as the difference signal 364 shown. In other examples, a smoothed difference signal may be calculated using, for example, a rolling median calculation. As described, in some examples, such a smoothed difference signal may include a discrete signal, such as one representative data point per second.

[0082] In one example, the system controller can be configured via the equation Z = TR t - TS- t-PT Determine the difference signal Z, where TR t It is the reflux turbidity value at time t (e.g., from reflux line sensor 322), and TS t-PT Z is the supply turbidity value at time t-PT (e.g., from supply line sensor 342), where PT is the time it takes for the fluid mass to flow between supply line sensor 342 and return line sensor 322. As discussed, such a difference signal can correspond to the difference in turbidity of the fluid mass measured before and after it flows through the industrial equipment 310 to be cleaned. Therefore, the difference signal Z can represent additional contaminants added to the fluid from the industrial equipment 310 being cleaned.

[0083] In some examples, the controller can be configured to determine the end of a CIP phase if the difference signal drops below a predetermined difference threshold. For example, in some cases, if the fluid flowing through the industrial equipment 310 to be cleaned does not affect the turbidity of the fluid (resulting in a low or zero difference signal), it can indicate that no cleaning process has been performed at the industrial equipment. Therefore, this can be used as an indication of CIP phase completion, and subsequent runs of the same phase may increase costs without providing any benefit. In some examples, determining the end of a CIP phase based on the difference signal also includes determining whether the difference signal has fallen below a predetermined difference threshold and remained below it for a predetermined amount of time. This reduces the likelihood of incorrectly determining CIP phase completion based on a single data point. In some examples, the end of a CIP phase corresponds to a change in turbidity caused by the equipment being below a threshold and remaining so. Figure 4 An example process flow diagram is shown, which involves using interpolation analysis to determine the end of the CIP stage.

[0084] In the illustrated example, the stripe count starts from zero (400). The process continues by analyzing the turbidity of the fluid mass at a first time and a second time to determine a first measured turbidity and a second measured turbidity (410), and determining the difference between the first measured turbidity and the second measured turbidity (420). As described herein, in some examples, this step includes comparing the turbidity of the fluid mass using two sensors positioned upstream and downstream of the industrial equipment to be cleaned. In other examples, this includes analyzing turbidity information acquired from a single sensor at multiple times.

[0085] The difference can be compared to a predetermined difference threshold (430). If the difference is not lower than the threshold, further turbidity analysis can be performed (410) and the process continues. If the difference is lower than the threshold, the stripe count can be incremented (440). The incremented stripe count can be compared to the stripe threshold (450), and if the stripe count is not higher than the stripe threshold, further turbidity analysis can be performed (410). However, in the illustrated example, if the stripe count is higher than the threshold, in some cases, indicating that the turbidity change remains low for at least the threshold duration, it can be determined that the end of the CIP phase has occurred (460).

[0086] In some examples, analyzing turbidity differences over a known time period involves determining the rate of change of turbidity over time. In some examples, determining whether the turbidity difference is below a threshold involves comparing the rate of change of turbidity to a turbidity change rate threshold. In some such examples, if the rate of change is below the rate of change threshold, it can be determined that the end of the CIP phase has occurred. In other examples, if a particular instance of the turbidity change rate is below the rate of change threshold, similar to step 440, the stripe count can be incremented, and if the stripe count rises above the stripe threshold, it can be determined that the end of the CIP phase has occurred, for example, where the turbidity change rate has remained low and persisted for the threshold time period.

[0087] Return to reference Figure 3C During the time window of 370, the turbidity difference between the return signal and the supply signal is low, indicating that the cleaned equipment does not release dirt and increase the turbidity of the fluid flowing through it. Similarly, in Figure 3D In the middle, the difference signal is lower during the 370-degree time window. Using a similar... Figure 4 In some cases, this method can determine that the end of the CIP phase has occurred during such a window. In some examples, the CIP phase can be stopped in response to determining that the end of the CIP phase has occurred. In some examples, refer to... Figure 3D It can be determined that the end of the CIP phase has occurred at or near the beginning of the time window 370, thus implying that ending the CIP phase during such detection can result in a time saving of some or all of the duration of the time window 370.

[0088] In some examples, turbidity difference signals or smoothed difference signals can be used to calculate continuous difference signals. Continuous difference signals may include data representing the differences between consecutive data points in the difference signal. Figure 3E An example continuous difference signal 368 is shown, which illustrates... Figure 3D The difference between consecutive points on the smoothed difference signal 366.

[0089] In some examples, the controller can be configured to determine the continuous difference signal by comparing successive measurements of the difference signal Z. In one example, the continuous difference SD = |Z t - Z t-1 |, where Z t It is the difference at time t, and Z t-1 This is a previous difference, for example, a difference calculated using the rolling median difference from one minute ago. In some examples, the difference between t and t-1 can be based on a difference measurement rate, and the difference between time t and t-1 can be, for example, one minute, two minutes, or other predetermined time difference. For example, using a one-minute time difference, the first consecutive difference can be calculated by taking the average (e.g., the median) of values ​​within a time range of 61 seconds to 120 seconds and subtracting the average (e.g., the median) of values ​​within a time range of 0 seconds to 60 seconds. In some examples, the time difference between t and t-1 corresponds to the amount of time used to determine the rolling median of the difference signal. In some examples, the time difference between t and t-1 corresponds to the time difference between consecutive smoothed data points (e.g., such that the consecutive difference is the difference between the current smoothed data point and the previously smoothed data point).

[0090] In some examples, continuous difference data can be used to determine the end of a CIP phase. For instance, if continuous difference data points (e.g., the difference between consecutive differences) are below a predetermined threshold, the turbidity change due to the cleaning of industrial equipment is stable over time. Figure 5 An example analysis of a continuous difference signal is shown to determine when the end of a phase of the CIP process has occurred. Figure 5 In the example, the stripe count starts from zero (500). This step continues to determine a difference signal (510) corresponding to the change in turbidity caused by the cleaned equipment, which can be determined using the process described herein. The process also includes calculating continuous differences (520), for example, as described herein. Continuous difference signals may include, for example, differences between consecutive points of a smoothed difference signal, such as the rolling median of difference data corresponding to consecutive minute data.

[0091] The continuous difference can be compared with a continuous difference threshold (530), and if the continuous difference is not lower than the threshold, additional difference signal information can be determined while the CIP phase continues (510). If the continuous difference is lower than the threshold, the stripe count can be incremented (540) and compared with the stripe threshold (550). If the stripe count is not higher than the threshold, additional difference signal information can be determined while the CIP phase continues (510). However, if the stripe count is higher than the stripe threshold, it can be determined that the end of the CIP phase has occurred (560).

[0092] In some examples, reference Figure 3EIt can be determined that the end of the CIP phase has occurred at or near the beginning of the time window 370, where the continuous difference signal is low and remains low. Therefore, in some such cases, ending the CIP phase during such detection can result in a time saving of some or all of the duration of the time window 370.

[0093] Figure 4 and Figure 5 Example procedures can be implemented, for example, by a controller that communicates with one or more turbidity sensors, as in the configuration described herein.

[0094] Although Figure 3A The examples shown herein include multiple turbidity sensors, but the various examples described herein can be implemented using a single turbidity sensor. Figure 6A An example CIP system is shown, which includes an industrial device 110 to be cleaned, a return line sensor 122 located downstream of the device 110, and other CIP system components 108, such as one or more pumps, valves, etc., that can be used to move fluid through the CIP system. Although shown as including a single return line sensor 122, in other examples, a single turbidity sensor may be located elsewhere in the CIP system, such as on the supply side of the device 110.

[0095] Figure 6B An example graph of the turbidity signal 650 from the turbidity sensor over time is shown. As shown, the turbidity signal 650 has periodic relative maximum and minimum values ​​over time. In some cases, this can be caused by a burst of contaminants discharged from the cleaned equipment, which causes localized high turbidity in the fluid flowing through the system. For example, in one example, the turbidity of a contaminant-containing fluid mass released from the cleaned equipment is analyzed at a first time t1 and a second time t2, where the difference between times t1 and t2 is the amount of time the fluid mass takes to circulate through the CIP system.

[0096] Similar to what is described elsewhere in this document, in some examples, a difference signal representing a change in turbidity for a given fluid mass can be determined using a signal 650 from a single sensor, for example, by subtracting the turbidity at time t2 from the turbidity at time t1. In some examples, a continuous difference signal can be calculated by determining the difference between the turbidity signal 650 and a turbidity signal pattern that is time-shifted by the time it takes for the fluid mass to circulate through the system. For example, in one example, the difference signal can be calculated using the equation Z=TR. t -TR t-pt To calculate, where TR t It is the turbidity at the reflux sensor at time t, and TR t-ptThe turbidity at the return sensor is the turbidity at a time offset from time t by a transit time pt, which corresponds to the amount of time the fluid mass takes to circulate through the CIP system. Regardless of whether a single sensor is located on the supply or return side of the device to be cleaned, the fluid mass will have traveled through the device between the times separated by the transit time pt, where the turbidity of the fluid mass may have been affected by contaminants leaving the device. In some examples, such single sensor data separated by a known time (in this example, the transit time pt) can be used to determine the rate of change of turbidity, which can be evaluated to determine whether the end of the CIP phase has occurred, as described elsewhere in this document.

[0097] Similar to the description above regarding dual-sensor designs, a difference signal can be generated from a single-sensor design, and, for example, if the difference signal drops below a threshold, or in some examples, remains below the threshold for a predetermined amount of time, this difference signal can be used to determine the end of the CIP phase. Alternatively or additionally, such a difference signal can be used to generate a smoothed difference signal, for example, by using the rolling median of the calculated difference signal over time. In some examples, continuous difference methods such as those described above regarding dual-sensor designs can be similarly applied to single-sensor designs. For example, in some examples, the continuous difference SD = Z. t -Z t-1 Similar to what was described above, where Z t It is the difference at time t, and Z t-1 It is the previous difference, for example, the difference calculated using the rolling median difference from one minute ago. In some examples, the time difference between t and t-1 is the amount of time between the previous smoothed difference signal data points.

[0098] In some examples, turbidity data over time, such as data from sensors, differential signals generated by a single sensor or multiple sensors, or continuous differential signals, can be fitted to a turbidity model. In some examples, fitting turbidity data to a model can be used to determine the end of a CIP phase. In some examples, the model can provide an estimated time after which the phase will complete. In some such cases, the estimated time can be updated after each new data point is computed (e.g., each new smoothed data point). Figure 6BThis includes a turbidity model 652 fitted to the turbidity signal 650. In some examples, model 652 can be used to determine the end of the CIP phase, such as when the model passes a predetermined point along the horizontal or vertical axis. In some examples, the turbidity data fitted to the model includes raw turbidity data, turbidity change rate data, periodically sampled turbidity data (e.g., turbidity data sampled from one or more sensors each time the turbidity of a fluid mass can be detected by one or more sensors), turbidity difference signals, or continuous difference data.

[0099] Various examples of analyzing turbidity at multiple time points have been described. For instance, in various examples, changes in the turbidity of the fluid mass can indicate that the CIP phase is not yet complete as the equipment to be cleaned continues to distribute dirt into the CIP system. However, various procedures can be used to determine the end of the CIP phase based on multiple turbidity measurements, as described herein.

[0100] In various examples, one or more thresholds are used (e.g., a count threshold, a turbidity difference threshold, a turbidity variation range threshold, etc.). The thresholds may be stored in memory (e.g., memory 228). The specific threshold stored in memory 228 may depend on, for example, the characteristics of the dirt being cleaned, the cleanliness requirements of the product produced using industrial equipment 10, the availability of various CIP cleaning fluids, the geometry and / or number of fluid flow paths, the number of fluid sources, or other system parameters.

[0101] In various examples, during the operation of CIP system 8, controller 30 can control system components to flush industrial equipment 10 with a pre-rinse fluid, for example, until the turbidity of the pre-rinse fluid reaches a steady state (e.g., turbidity difference, rate of change of turbidity, or other measure meets one or more thresholds, as described herein). At this point, controller 30 can control CIP system 8 to terminate the pre-rinse phase and begin a cleaning phase, such as an alkaline washing phase. Similar steps can be performed where controller 30 can control system components, for example, to circulate alkaline chemicals through the equipment to be cleaned to remove contaminants therefrom, until the turbidity of the system reaches a steady state. Such a steady state indicates that the contaminants targeted in the alkaline washing phase have been substantially removed from the equipment and / or the chemicals have been consumed. At this point, controller 30 can control CIP system 8 to terminate the alkaline washing phase and begin a new phase, such as a rinsing phase. Individual phases can be controlled in a similar manner.

[0102] In some examples, the system may be configured to generate output indicating that a phase has ended. For example, such output may be provided via a user interface that communicates with the controller (e.g., wired or wirelessly). Example interfaces may include a display screen located near and connected to the controller of the CIP system, or a networking interface that communicates with the controller via a network. In some examples, the controller may be configured to send a notification that a CIP phase has ended, for example, via email, text message, or other telecommunications methods.

[0103] The techniques described in this disclosure, including functions performed by a controller, control unit, or control system, can be implemented within one or more of a general-purpose microprocessor, digital signal processor (DSP), application-specific integrated circuit (ASIC), field-programmable gate array (FPGA), programmable logic device (PLD), or other equivalent logic device. Therefore, as used herein, the terms "processor" or "controller" may refer to any one or more of the foregoing structures or any other structure suitable for implementing the techniques described herein.

[0104] The various components illustrated herein can be implemented through any suitable combination of hardware, software, and firmware. In the accompanying drawings, the various components are depicted as individual units or modules. However, all or several of the components described with reference to these drawings can be integrated into a combined unit or module within general-purpose hardware, firmware, and / or software. Therefore, representing features as components, units, or modules is intended to highlight specific functional characteristics for ease of illustration and does not necessarily require implementation of such characteristics by separate hardware, firmware, or software components. In some cases, the various units can be implemented as programmable processes executed by one or more processors or controllers.

[0105] In some examples, one or more processors or controllers may utilize additional processing resources, such as cloud-based resources. For instance, in some cases, the system may include a local controller that communicates with various local devices within the system, such as sensors, pumps, and valves. The local controller may be configured to transmit data to a remote location, such as a cloud-based computing platform, for data analysis. One or more processing steps described herein may be performed at a remote location (e.g., via cloud computing), and the local controller may be configured to receive the results of one or more such processing steps. The local controller may be configured to engage with other local components based on the results of remote processing.

[0106] Any feature described herein as a module, device, or component may be implemented together in an integrated logic device or separately as discrete but interoperable logic devices. In various respects, such a component may at least partially be configured as one or more integrated circuit devices, which may be collectively referred to as integrated circuit devices, such as integrated circuit chips or chipsets. Such circuitry may be provided in a single integrated circuit chip device or in multiple interoperable integrated circuit chip devices.

[0107] If implemented in part by software, the technology can be implemented at least in part by a computer-readable data storage medium (e.g., a non-transitory computer-readable storage medium) including code with instructions that, when executed by one or more processors or controllers, perform one or more methods and functions described in this disclosure. The computer-readable storage medium can form part of a computer program product, which may include packaging material. The computer-readable medium may include random access memory (RAM), such as synchronous dynamic random access memory (SDRAM), read-only memory (ROM), non-volatile random access memory (NVRAM), electrically erasable programmable read-only memory (EEPROM), embedded dynamic random access memory (eDRAM), static random access memory (SRAM), flash memory, magnetic or optical data storage media. Any software used can be executed by one or more processors, such as one or more DSPs, general-purpose microprocessors, ASICs, FPGAs, or other equivalent integrated or discrete logic circuits.

[0108] The following embodiments may provide additional details regarding the CIP system and technology according to this disclosure.

Claims

1. A method, the method comprising: During a phase of the Clean In-Situ (CIP) process, fluid is guided through a fluid path that includes industrial equipment to remove contaminants from the industrial equipment. The turbidity of the fluid mass within the fluid path is analyzed in the first instance to provide a first measurement of the turbidity of the fluid mass; The turbidity of the fluid mass within the fluid path is analyzed at a second time to provide a second measured turbidity of the fluid mass, wherein the fluid mass travels through the industrial equipment between the first time and the second time; The end of the phase of the CIP process is determined based on the first and second measured turbidity. as well as The CIP process is controlled based on the end of the determined phase of the CIP process.

2. The method according to claim 1, wherein: Guiding the fluid through the fluid path includes recirculating the fluid through a recirculation loop; Analyzing the turbidity of the fluid mass in the first instance includes measuring the turbidity of the fluid mass at a first location within the fluid path using a turbidity sensor; Analyzing the turbidity of the fluid mass at a second time includes measuring the turbidity of the fluid mass at the first location using the turbidity sensor; and The first time and the second time are time-shifted by the amount of time it takes for the fluid mass to complete one cycle through the recirculation loop of the fluid path.

3. The method according to claim 2, wherein, Determining the end of a phase of the CIP process based on the first and second measured turbidity includes: Determine the difference between the first measured turbidity and the second measured turbidity; The determined difference is compared with a predetermined difference threshold; and If the determined difference is less than the predetermined difference threshold, then it is determined that the end of the phase of the CIP process has occurred.

4. The method according to claim 1, wherein, Determining the end of the phase of the CIP process based on the first measured turbidity and the second measured turbidity includes: Determine the difference between the first measured turbidity and the second measured turbidity; The determined difference is compared with a predetermined difference threshold; and If the determined difference is less than the predetermined difference threshold, then the run count of consecutive instances of measured turbidity differences below the predetermined difference threshold is incremented; and If the run count of consecutive instances of measured turbidity differences below the predetermined difference threshold meets the predetermined stripe threshold, then it is determined that the end of the phase of the CIP process has occurred.

5. The method according to claim 1, wherein: Analyzing the turbidity of the fluid mass at the first moment includes measuring the turbidity of the fluid mass at a first location within the fluid path using a first turbidity sensor; The second time-based analysis of the turbidity of the fluid mass includes measuring the turbidity of the fluid mass at a second location within the fluid path using a second turbidity sensor, the second location being different from the first location; and The first time and the second time are time-shifted by the amount of time the fluid mass takes to travel through the fluid path between the first position and the second position.

6. The method according to claim 5, wherein, Guiding the fluid through the fluid path includes recirculating the fluid through a recirculation loop; Measuring the turbidity of the fluid mass using the first turbidity sensor includes continuously measuring the turbidity of the fluid by the first turbidity sensor as the fluid flows through the recirculation loop to provide a first continuous turbidity measurement; and Measuring the turbidity of the fluid mass using a second turbidity sensor includes continuously measuring the turbidity of the fluid by the second turbidity sensor as the fluid flows through the recirculation loop to provide a second continuous turbidity signal.

7. The method according to claim 6, further comprising: A turbidity difference signal is calculated, the turbidity difference signal comprising the difference between a first continuously measured turbidity signal and a second continuously measured turbidity signal offset in time, the second continuously measured turbidity signal offset in time from the amount of time taken for the fluid mass to travel through the fluid path between the first position and the second position; and wherein... Determining the end of a phase of the CIP process based on the first and second measured turbidity includes determining the end of the phase of the CIP process based on the turbidity difference signal.

8. The method according to claim 7, wherein, Determining the end of a phase of the CIP process based on the turbidity difference signal includes: if the turbidity difference signal is less than a predetermined difference threshold and continues for a predetermined time period, then the phase of the CIP process is determined to have ended.

9. The method of claim 7, further comprising determining a smoothing difference signal based on the turbidity difference signal, and wherein determining the end of the phase of the CIP process based on the turbidity difference signal comprises: If the smoothed difference signal is less than a predetermined difference threshold and continues for a predetermined period of time, then it is determined that the phase of the CIP process has ended.

10. The method according to claim 9, wherein, Determining the smoothed difference signal includes calculating the rolling median or rolling average of the turbidity difference signal over time.

11. The method according to claim 1, further comprising: Determine the difference between the first measured turbidity and the second measured turbidity; The difference between the determined first measured turbidity and the second measured turbidity is compared with a predetermined difference threshold. as well as If the difference between the first measured turbidity and the second measured turbidity is less than the predetermined difference threshold, then it is determined that the end of the phase of the CIP process has occurred.

12. The method according to claim 11, further comprising: If the difference between the first measured turbidity and the second measured turbidity is not less than the predetermined difference threshold, then: The turbidity of the fluid mass within the fluid path is analyzed at a third time to provide a third measurement of the turbidity of the fluid mass, wherein the fluid mass travels through the industrial equipment between the second time and the third time; Determine the difference between the second measured turbidity and the third measured turbidity; The difference between the determined second measured turbidity and the third measured turbidity is compared with the predetermined difference threshold. as well as If the difference between the second measured turbidity and the third measured turbidity is less than the predetermined difference threshold, then it is determined that the end of the phase of the CIP process has occurred.

13. The method according to claim 1, further comprising: Acquire turbidity data over a period of time, wherein the period of time includes the first time and the second time; And among them, Determining the end of the phase of the CIP process based on the first and second measured turbidity includes fitting the turbidity data over time to a turbidity model.

14. The method according to claim 1, further comprising: Acquire turbidity data over a period of time, wherein the period of time includes the first time and the second time; And among them, Determining the end of a phase of the CIP process based on the first and second measured turbidity includes: Determine the rate of change of the turbidity data over time; and If the rate of change of the turbidity data over time meets a predetermined turbidity change rate threshold condition, then it is determined that the end of the CIP process has occurred.

15. The method according to claim 1, wherein, The phases of the CIP process include an alkaline cycling phase.

16. The method according to claim 1, wherein, Determining the end of a phase of the CIP process based on the first and second turbidity measurements includes predicting the future endpoint of the phase of the CIP process based on the first and second turbidity measurements.

17. The method according to claim 1, wherein, The industrial equipment includes one or more of heat exchangers, tanks, pipes, filters, and valves.

18. The method according to claim 1, wherein, Controlling the CIP process based on the end of the determined phase of the CIP process includes electronically controlling the CIP process.

19. The method according to claim 18, wherein, The electronically controlled CIP process includes at least one of the following: adjusting the rate at which the fluid is guided through the industrial equipment, stopping the flow of the fluid through the industrial equipment, and adjusting the chemical composition of the fluid.

20. The method of claim 18, wherein: The phase of the CIP process is the cleaning phase; and At the end of the phase, the electronically controlled CIP process includes terminating the cleaning phase and initiating the rinsing phase.

21. The method according to claim 1, wherein, The fluid mass comprises a fluid volume that flows through a predetermined length of the fluid path within a predetermined time period.

22. A measurement and control system for a Clean In-Situ (CIP) process, the system comprising: A turbidity sensor is positioned in the fluid path of a CIP process, the fluid path including industrial equipment, and the CIP process removes contaminants from the industrial equipment; as well as A controller, which communicates with the turbidity sensor and is configured to: Receive turbidity information from the turbidity sensor, indicating the turbidity of fluid masses in the fluid path; A first measured turbidity of the fluid mass is determined based on the turbidity information received from the turbidity sensor, wherein the first measured turbidity represents the turbidity of the fluid mass at a first time. A second measured turbidity of the fluid mass is determined, the second measured turbidity representing the turbidity of the fluid mass at a second time, wherein the fluid mass travels through the industrial equipment in the fluid path between the first time and the second time; The end of a phase of the CIP process is determined based on the first and second measured turbidity. as well as The CIP process is controlled based on the end of the determined phase of the CIP process.

23. The system according to claim 22, wherein, The fluid path includes a recirculation loop, through which the fluid mass flows during the phase of the CIP process; The first time and the second time are temporally offset by the amount of time it takes for the fluid mass to complete one cycle through the recirculation loop of the fluid path; and Determining the second measured turbidity of the fluid mass includes determining the second measured turbidity based on turbidity information received from the turbidity sensor.

24. The system according to claim 23, wherein, Determining the end of a phase of the CIP process based on the first and second measured turbidity includes: Determine the difference between the first measured turbidity and the second measured turbidity; The determined difference is compared with a predetermined difference threshold; and If the determined difference is less than the predetermined difference threshold, then it is determined that the end of the phase of the CIP process has occurred.

25. The system according to claim 22, wherein, Determining the end of the phase of the CIP process based on the first measured turbidity and the second measured turbidity includes: Determine the difference between the first measured turbidity and the second measured turbidity; The determined difference is compared with a predetermined difference threshold; and If the determined difference is less than the predetermined difference threshold, then the run count of consecutive instances of measured turbidity differences below the predetermined difference threshold is incremented; and If the run count of consecutive instances of measured turbidity differences below the predetermined difference threshold meets the predetermined stripe threshold, then it is determined that the end of the phase of the CIP process has occurred.

26. The system according to claim 22, wherein, The turbidity sensor includes a first turbidity sensor located at a first position in the fluid path, and the system further includes a second turbidity sensor located at a second position in the fluid path; and wherein, Determining the first measured turbidity of the fluid mass includes measuring the turbidity of the fluid mass using the first turbidity sensor at a first time. Determining the second measured turbidity of the fluid mass includes measuring the turbidity of the fluid mass using a second turbidity sensor at a second time; and The first time and the second time are time-shifted by the amount of time the fluid mass takes to travel through the fluid path between the first position and the second position.

27. The system according to claim 26, wherein: The fluid path includes a recirculation loop, through which the fluid mass flows during the phase of the CIP process; and The controller is configured to: The turbidity of the fluid is continuously determined using the first turbidity sensor to determine a first continuous measurement turbidity signal; and The turbidity of the fluid is continuously determined using the second turbidity sensor to determine a second continuous measurement turbidity signal.

28. The system according to claim 27, wherein: The controller is configured to calculate a turbidity difference signal, which includes the difference between a first continuously measured turbidity signal and a second continuously measured turbidity signal offset in time. The second continuously measured turbidity signal offset in time includes a second continuous turbidity signal, which is offset in time by the amount of time the fluid mass takes to travel along the fluid path between the first position and the second position. Determining the end of a phase of the CIP process based on the first and second measured turbidity includes determining the end of the phase of the CIP process based on the turbidity difference signal.

29. The system according to claim 28, wherein, Determining the end of a phase of the CIP process based on the turbidity difference signal includes: if the turbidity difference signal is less than a predetermined difference threshold and continues for a predetermined time period, then the phase of the CIP process is determined to have ended.

30. The system according to claim 22, wherein, The controller is further configured to: Determine the difference between the first measured turbidity and the second measured turbidity; If the difference between the first measured turbidity and the second measured turbidity meets a predetermined difference threshold, then it is determined that the end of the phase of the CIP process has occurred.

31. The system according to claim 30, wherein, The controller is further configured to: if the difference between the first measured turbidity and the second measured turbidity does not meet the predetermined difference threshold, then: A third measurement of turbidity is determined, the third measurement of turbidity representing the turbidity of the fluid mass at a third time, wherein the fluid mass travels through the industrial equipment between the second time and the third time; Determine the difference between the second measured turbidity and the third measured turbidity; If the difference between the second measured turbidity and the third measured turbidity satisfies the predetermined difference threshold, then it is determined that the end of the phase of the CIP process has occurred.

32. The system according to claim 22, wherein, The controller is configured to: Acquire turbidity data over a period of time, wherein the period of time includes the first time and the second time; Fit the acquired turbidity data over the specified time period to a turbidity data model; and The end of the phase of the CIP process is determined based on the turbidity data model.

33. The system according to claim 22, wherein: The controller is configured to acquire turbidity data over a period of time, the period of time including the first time and the second time. and Determining the end of the phase of the CIP process based on the first measured turbidity and the second measured turbidity includes: Determine the rate of change of the turbidity data over time; as well as If the rate of change of the turbidity data over time meets a predetermined turbidity change rate threshold condition, then it is determined that the end of the CIP process has occurred.

34. The system according to claim 22, wherein, The phases of the CIP process include an alkaline cycling phase.

35. The system according to claim 22, wherein, Determining the end of a phase of the CIP process based on the first and second turbidity measurements includes predicting the future endpoint of the phase of the CIP process based on the first and second turbidity measurements.

36. The system according to claim 22, wherein, The industrial equipment includes one or more of heat exchangers, tanks, pipes, filters, and valves.

37. The system according to claim 22, wherein, The controller is configured to perform at least one of the following: adjusting the rate at which the fluid is directed through the industrial equipment, stopping the flow of the fluid through the industrial equipment, and adjusting the chemical composition of the fluid.

38. The system according to claim 37, wherein: The CIP process is a cleaning phase; and The controller is configured to terminate the cleaning phase and initiate the rinsing phase.

39. The system of claim 37, further comprising one or more valves positioned in the fluid path, wherein: The controller communicates with the one or more valves and is configured to electronically control the fluid flow through the one or more valves; and The controller is configured to control the CIP process by opening and / or closing at least one of the one or more valves.

40. The system according to claim 22, wherein, The fluid mass comprises a fluid volume that flows through a predetermined length of the fluid path within a predetermined time period.

41. The system according to claim 22, wherein, The controller is configured to use a cloud-based computing platform to determine the end of the phase of the CIP process based on the first measured turbidity and the second measured turbidity.

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