TEMPERATURE CONTROL OF PRESSURE VESSELS FOR BULK PROCESSING IN HIGH-PRESSURE APPLICATIONS.
Patent Information
- Authority / Receiving Office
- MX · MX
- Patent Type
- Patents
- Current Assignee / Owner
- AVURE TECHNOLOGIES INC
- Filing Date
- 2022-09-23
- Publication Date
- 2026-06-12
Smart Images
Figure MX435036B0
Abstract
Description
TEMPERATURE CONTROL OF PRESSURE VESSELS FOR BULK PROCESSING IN HIGH-PRESSURE APPLICATIONS CROSS REFERENCE TO RELATED APPLICATIONS This patent application claims priority over U.S. patent application serial number 63 / 006,550, filed on April 7, 2020. This patent application also claims priority over U.S. patent application serial number 63 / 001,113, filed on March 27, 2020, the full disclosures of which are incorporated herein by reference for all purposes. BACKGROUND OF THE INVENTION High-pressure processing (HPP) is used to reduce the microbial load in food, beverages, cosmetics, pharmaceuticals, and other products without altering the characteristics of the processed product. The pressure level required for successful HPP is typically at least 200,000 kPa (2,000 bar). Traditional HPP equipment for processing beverages and other liquids, as well as pumpable foods and other substances, relies on processing the products after they have been placed as individual units in flexible packaging, such as bottles, cartons, or pouches. The individual units are then grouped or consolidated within a larger, reusable loading basket that is sized and shaped to fit inside a wire-wound high-pressure vessel (also called a "wire-wound vessel" or "high-pressure vessel"). This high-pressure vessel is filled with water, which serves as the pressurizing medium. Once the wire vessel is filled and sealed, high-capacity pumps introduce additional water into the pressure vessel, increasing the pressure from approximately 200,000 to 1,000,000 kPa (2,000 to 10,000 bar). This pressure is maintained for a sufficient time, from a few seconds to several minutes, to reduce the microbial load of the products being treated. The specific pressure level and duration are determined by the product being processed. Once the desired level of microorganism inactivation is reached, the pressure in the container is released and the loading basket is removed, allowing the individual packages or units to be extracted. The processed product, after being exposed to high pressure and holding time, is pasteurized, resulting in a reduced microbial load and an extended shelf life. High-pressure applications for food products are run at lower temperatures, typically between 2 and 30°C, due to the need to maintain the cold chain. A high-pressure food application is typically run with water or media pressure levels exceeding 200,000 kPa (2,000 bar) and hold times of more than 20 seconds (typically 600,000 kPa (6,000 bar) with a 3-minute hold time). However, some food products are required to reach a specific minimum temperature that is higher than the temperatures typically used in high-pressure processing. This description addresses this deficiency and offers other advantages. BRIEF DESCRIPTION OF THE INVENTION This disclosure addresses the use of very high pressures and higher process temperatures to treat products. In the past, high-pressure processing was used to reduce microbial counts in many types of food and other products. In this disclosure, “product” is intended to cover, for example, food products, cosmetics, pharmaceuticals, and various types of organic substances. In the past, the objective of high-pressure processing was to maintain the product at a relatively low temperature, typically 4 to 29°C. Water is used as a pressure medium to apply high pressure to the products being processed. Intensifiers are used to increase the water pressure to the desired level. When this pressure is applied, the water experiences an adiabatic temperature rise of approximately 3°C per 100,000 kPa (1,000 bar). This adiabatic temperature rise has not typically been a problem in the past because the water starts at a sufficiently low temperature to remain within the desired temperature range, despite the adiabatic increase. Once the pressure is released, the temperature of both the water and the processed product begin to decrease accordingly. However, some regulations require heat treatment at specific minimum temperatures for certain products. To comply with regulations for milk processing, for example, milk must be heated, preferably, to 55°C and maintained within a relatively close temperature range. According to the present description, the pressure vessel is equipped with one or more heating and cooling systems to control the temperature range to meet any temperature requirement for the products, while they are being pressurized. In one modality, the pressure medium is used to heat or cool the pressure vessel and / or the products it contains, using a temperature sensor system that provides feedback to a controller. In one mode, the controller takes the adiabatic temperature rise into account when calculating the pressure medium temperature to meet any desired processing temperature for the particular product. In one mode, the temperature of the water from the pressure medium to the pressure vessel is monitored, and the adiabatic temperature rise and fall of the water are calculated as a function of the processing pressure. When a different pressure medium is used, the adiabatic temperature rise can also be calculated for that specific pressure medium. In a configuration where a pressure vessel is surrounded by an oil bath, the oil bath can be converted into oil-filled thermal insulation by recirculating the oil through an auxiliary heating and cooling system. The oil-filled thermal insulation partially surrounds the pressure vessel, within which there are one or more baskets and / or containers holding the products. Consequently, the oil-filled thermal insulation can be used to apply or remove heat from the vessel. In one embodiment, a heating layer can be wrapped around the pressure vessel. The heating layer supplies heat via electrical resistance heating elements. In addition to the oil-filled thermal insulation, the heating layer, and the pressure vessel, other heating and cooling systems can also be constructed to apply or remove heat from the pressure vessel to control processing temperatures. In one instance, the objective of this description is to control processing temperatures while pressurizing the product. In this way, the product undergoes inactivation of microorganisms through both pressure and heat. In other configurations, the product may be sensitive to the high temperatures caused by adiabatic heating. In such cases, the purpose of this description is not to subject the product to harmful high temperatures while processing it under high pressure for microorganism inactivation. Consequently, the high-pressure processing system may also be equipped with cooling and heating systems, both controlled by a single controller. The system described in this disclosure can be used to process products at high pressures with controlled temperatures within desired ranges, which has not been the case for other high-pressure processing systems. In general, processing temperatures were allowed to fluctuate according to the adiabatic temperature rise for a given pressure. In this description, the temperature is actively monitored and controlled within a desired range. This description offers several advantages. For example, as previously explained, the system is useful in dairy processing. The system can also be used at operating temperatures of at least 130 °C or higher, in high-temperature and high-pressure sterilization applications. Such operating pressures can be as high as 800,000 kPa (8,000 bar) or even higher. Thus, for example, the system described here can be used for pressure-assisted temperature sterilization (PATS) or temperature-assisted pressure sterilization (TAPS). This summary is provided to present a selection of concepts in a simplified form, which are described further in the detailed description. This summary is not intended to identify the key features of the claimed object, nor is it intended to be used as an aid in determining the scope of the claimed object. BRIEF DESCRIPTION OF THE FIGURES The foregoing aspects and many of the concomitant advantages of this invention will be more readily appreciated as they are better understood with reference to the following detailed description, when taken together with the accompanying figures, in which: FIGURE 1 is a schematic illustration of one modality of a high-pressure processing system, according to one modality. FIGURE 2 is a schematic illustration of one modality of a high-pressure processing system with process temperature control. FIGURE 3 is a schematic illustration of one modality of a high-pressure processing system with process temperature control. FIGURE 4 is a schematic illustration of a temperature control system for high-pressure processing according to the modalities of this description. DETAILED DESCRIPTION OF THE INVENTION In one embodiment, this description provides a temperature control system for processing products, such as dairy products, in a high-pressure processing (HPP) vessel. With this system and method, the temperature inside the pressure vessel can be maintained within a very narrow temperature range necessary for the product, such as a dairy or other food product, to achieve its desired parameters or characteristics, such as nutritional value, shelf life, and the like. Dairy and other food products may be used as examples in this description to illustrate aspects of temperature control during high-pressure processing; however, the description is not limited to any particular product. This application relates to a “product” or “products” that are subjected to or treated by temperature-controlled high-pressure processing as described herein. Such products may include all types of food, including pumpable foods or beverages, as well as non-food products such as cosmetics, pharmaceuticals, and organic materials and substances where pathogen control is desirable. ΜΛ / a / ZUZZ / UI Ί »4 1 microorganisms. For example, a “dairy product” is any product manufactured from or derived from ruminant animals, such as cows, goats, sheep, deer, and the like. Dairy products are described as representative examples of products. However, products are not limited to dairy or food products; they can also include items that benefit from the deactivation of microorganisms, such as cosmetics, pharmaceuticals, and various types of organic materials and substances. High-pressure processing in current food applications is carried out at the lowest possible temperatures (typically 4-292C) so as not to interrupt the cold chain, which is usually key to establishing the desired shelf life. For dairy products and others, for example, a higher temperature must be achieved. For instance, dairy products must be exposed to a minimum of approximately 55°C. In one embodiment, the present system aims to achieve high-pressure processing with temperature control in the range of approximately 45 to 65°C. High-pressure food processing is, in many ways, a superior method for achieving microbial inactivation in food because it does not rely on high temperatures that can destroy or ruin the food's nutrition, flavor, and texture. Using high pressure and holding time extends shelf life and preserves nutrition. Furthermore, high pressure and holding time allow food manufacturers to use a clean label and avoid the need for preservatives to extend shelf life. However, as the examples show, further heating or cooling of some products may be desirable. High-pressure vessels have been commercially available for over 25 years. They come in various configurations and sizes. However, all systems include a pressure vessel capable of withstanding very high pressure levels. The most common pressure medium used is water, but water with additives can also be used. This disclosure applies to the retrofitting of existing pressure vessels with temperature control systems, or to the construction of new pressure vessels with temperature control systems. Figure 1 is a schematic illustration of one embodiment of this disclosure, of a high-pressure processing system 100 capable of achieving product temperature control during high-pressure processing, while Figures 2 and 3 are schematic illustrations of a high-pressure processing system 300 illustrating the main components used in temperature control. Other features not shown are standard features of existing high-pressure processing systems. In one embodiment, the systems can be used to process a product, such as milk, particularly in the range of approximately 45 to 65°C. Figure 4 is a schematic illustration of a temperature control system showing the main components for use in high-pressure processing. With reference to FIGURE 1, in a high-pressure processing modality, a basket 102 is used to contain one or more food packages, such as bottles, cartons, or bags, in which the high-pressure processing system 100 can process pumpable products while maintaining a controlled temperature within a range. However, the disclosure is not limited to pumpable liquid products and may also apply to solid and non-pumpable products. It is understood that a basket 102 is merely representative of an example for containing the products to be processed in the system 100. Other containers may be used. Furthermore, the applications entitled “Reusable Container for Bulk Processing in High Pressure Application,” U.S. Provisional Application No. 63 / 001119, filed March 27, 2020, and “Load basket for Thermal Management for Processing in High Pressure Application,” U.S. Provisional Application No. 63 / 001119, filed March 27, 2020, and “Load basket for Thermal Management for Processing in High Pressure Application,” U.S. Provisional Application No. 63 / 001119, filed March 27, 2020, are also relevant.number 63 / 001047, submitted on March 27, 2020, are incorporated into this document, expressly as a reference, for each and every purpose. In high-pressure processing, when the pressure medium and the product are pressurized, the adiabatic temperature rise will increase the temperature of both. A typical temperature rise is about 3°C per 100,000 kPa (1,000 bar), resulting in about 18°C at a normal operating pressure of 600,000 kPa (6,000 bar). Once the pressure is released, the temperature decreases. It is understood that different materials, foods, and pressure media may exhibit different adiabatic temperature rises. However, even under a pressure of 600,000 kPa (6,000 bar), the adiabatic temperature rise is insufficient to achieve temperature ranges of around 45 to 65°C. Furthermore, since high-pressure applications are run in cool environments, all the equipment used for the high-pressure application operates at a low temperature. During downtime, the system will cool both the pressurized media and the product exposed to the pressurized media in the generally low-temperature environment of the room. This cooling of the pressurized media and the product during downtime will result in the unfavorable condition that the desired temperature accuracy will not be achieved throughout the entire press cycle.Therefore, the present description provides a system that can control temperatures in certain places in the process, including the temperature of the pressure medium, the temperature of the product itself, and also calculates the adiabatic temperature rise for a given pressure, making precise temperature control possible in combination with high-pressure processing. This disclosure provides a high-pressure processing system with temperature control of the processing locations or the product itself by collecting data, evaluating data, and adjusting external parameters that will affect the product temperature. In one example, an external parameter that is temperature-controlled is the water or pressure media that will benefit from the adiabatic temperature increase. A 316 heat exchanger may be suitable for this purpose (see FIGURE 2). In one example, another external parameter for achieving heating and / or cooling of the processing and product temperatures is through temperature control of the oil-filled thermal insulation 324 surrounding the pressure vessel 326 (see FIGURE 2). The oil-filled thermal insulation 324 is the vacuum between the outermost layer of the pressure vessel 326 and the surrounding sheet metal cover. This vacuum is normally filled with oil to reduce condensation, for example. However, in one embodiment, an auxiliary oil heating and cooling system 332 is connected to heat and cool this oil. With precise control of the oil temperature, there is no risk of overheating the pressure vessel 326 and its internal parts.In this disclosure, oil is described as a heat transfer medium; however, the disclosure can be practiced with any other heat transfer medium suitable for the purpose. In one embodiment, due to the mass of the pressure vessel 326, the heat provided by the auxiliary oil heating and cooling 332 and the pressure media heat exchanger 316 may not be sufficient to respond quickly enough to bring the incoming product to the desired temperature range. High-pressure processing times for some products can range from a few seconds to several minutes. Consequently, in one embodiment, the temperature of the incoming product in basket 102 or another container to be processed must be fully controlled to ensure repeatable and reproducible results until the desired temperature is reached. To this end, the temperature of the incoming product must be sufficiently stable and consistent within a desired temperature range in a basket or other container. A temperature sensor 322I can be used to measure the temperature of the incoming product in basket 102 (see Figure 1).Such a 322I temperature sensor could be a thermal scanner, for example. To further help stabilize the incoming product temperature prior to high-pressure processing, the product may be cooled or heated within a predetermined temperature range, or the product may be allowed to reach ambient temperature for a period of time. The temperature of a product exiting the pressure vessel can also be measured using a 322 temperature sensor, and the temperature can be used in any control circuit to adjust the product temperature before or during high-pressure processing. Food temperature measurements can be performed using temperature sensors that are in contact with the food, but also with other types of sensors, for example, thermal imaging or infrared cameras. Continuing with reference to FIGURE 2, in general, the pressure vessel 326 functions to subject the product 320 to high pressure using a high-pressure medium, such as water. For this purpose, the system 300 is equipped with pumping and decompression systems for the pressurized medium. The high-pressure vessel 326 is supported on a frame composed of a longitudinal frame structure 302 and an end frame structure 304. The frame structure is any rigid structure capable of providing the structural functionality for the high-pressure processing described in this document. To retain the pressure media within the pressure vessel 326, in one embodiment, there is a closure / plug 306, 308 at each end of the pressure vessel 326. The closures 306, 308 float freely and will be pushed outward during pressurization. The closures 306, 308 are held in place by the frame 302 acting as a yoke. However, this disclosure may also apply to different pressure vessel designs. For example, a pressure vessel may use different frame / fork designs, including both wound wire frames and plate frames. This disclosure also applies to smaller pressure vessels that may omit a frame. In such cases, the closures are held in place by another type of locking system, such as a pin closure design, interrupted thread design, etc. The pressure vessel can also use different cylinder designs and both wire-wound cylinders / vessels and monolithic cylinders / vessels that can withstand the high pressure described in this application. Adding a temperature control system to a high-pressure processing system can be tailored to the specific type of pressure vessel. Temperature control systems can utilize existing systems, such as oil-filled thermal insulation and water-based heat exchangers, by adjusting these systems with temperature sensors connected to a controller. In other applications, it may be necessary to add a completely new temperature control system to the high-pressure processing system, which includes pressure vessels that do not have oil-filled thermal insulation. For example, a heating layer can be replaced with oil-filled thermal insulation as the temperature control system. In one embodiment, the high-pressure processing system 300 also includes one or more high-pressure pumps 310, water modules 312, electrical cubicles including a programmable logic controller 314 and communication cables and other significant components, material handling and auxiliary hydraulic unit(s). In one mode, the water module 312 supplies water to the pressure vessel 326 during prefilling, as well as to all high-pressure pumps / intensifiers during the pressure level increase stage. The water supplied by water module 312 to pressure vessel 326 is normally cooled by heat exchanger 316 to maintain the process as cool as possible, typically between 2 and 30°C. This temperature range has been found to be optimal from both a process and component life perspective. In one embodiment, water module 312, in addition to heat exchanger 316, is also equipped with heating elements to adjust the water temperature as required for temperature control of the high-pressure processing system. In one embodiment, the heat exchanger may be provided with a heat transfer medium or a coolant to heat or cool the water, or both. When water from water module 312 fills pressure vessel 326, the pre-filled water volume is at the set temperature. When high-pressure pumps 310 begin to increase the pressure level in pressure vessel 326, they receive water from water module 312 (at the preset temperature). As the pressure inside pressure vessel 326 and the high-pressure piping increases, the adiabatic temperature rise raises the temperature of both the water and the product being processed. A typical adiabatic temperature rise is 3°C per 100,000 kPa (1,000 bar), or 18°C at 600,000 kPa (6,000 bar). During the waiting period, typically between 30 seconds and 15 minutes, the increase or decrease in the temperature of the pressure medium (water) inside the pressure vessel 326 is monitored by measuring temperatures at specific locations using multiple temperature sensors 322a-n. The temperature sensors 322a-n can use any temperature measurement technology, including, but not limited to, thermocouples, thermistors, resistance temperature detectors (RTDs), infrared cameras, thermal imaging cameras, and similar devices. A programmable logic controller (PLC) 314 uses any or more of the temperature measurements in feedback and / or feedforward control loops. Consequently, when the process temperature is high according to a particular preprogrammed logic, there may be a need to apply cooling to the pressure medium or the oil in the oil-filled thermal insulation 324, while in cases where the process temperature is low, it may be necessary to heat the pressure medium or the oil. The process temperature may refer to any of the locations designated in this document, or any other suitable location where advantageous. In some examples, the temperature of the pressure medium and the oil is used to control an internal temperature of the system or of the product itself 320. In some cases, the metal parts will experience a temperature increase followed by a stable temperature after a greater number of cycles are run in the 326 pressure vessel. It is therefore important to adjust the temperatures according to the pre-programmed settings. In one mode, the 314 controller can compensate for this initial temperature increase followed by a stable temperature plateau. To illustrate, during a pressure cycle, controller 314 can target both the product and the pressure vessel and medium at approximately the same initial temperature (e.g., 37°C). Due to adiabatic temperature rise, the pressure medium and the product can reach a similar temperature (e.g., 55–57°C) at full pressure. Since pressure vessel 326 responds slowly due to its large mass of metal, its interior may warm up slightly and exhibit a temperature slightly higher than the initial temperature (e.g., 37°C). When consecutive cycles are run (each cycle with fresh baskets / milk / food products), it is possible for the inner surface of pressure vessel 326 to experience a steady increase in its temperature.In one mode, controller 314 is programmed with a formula to compensate for the temperature increase inside pressure vessel 326 after each series of consecutive cycles. It responds by gradually reducing the temperature of the vessel or the incoming product, for example, until the temperature of pressure vessel 326 stabilizes. Consequently, the risk of the milk / food products being exposed to excessively high temperatures is reduced or eliminated. In one mode, the product may undergo more than one cycle. In this case, the 314 controller is programmed with a recipe that compensates for the temperature increase during each cycle. The recipe can be validated by performing learning tests before using it for actual product production. When processing certain products, such as dairy products, it is important to reach specific product temperatures for a certain period of time (holding time). To achieve this temperature within reasonable tolerances, the combination of temperature control of pressure media, oil in the oil-filled thermal insulation 324, adiabatic temperature rise, and additional heating or cooling from ambient temperature in the room where the high-pressure processing takes place is controlled by the programmable logic controller 314. Consequently, the high-pressure processing of dairy products at pressures above 200,000 kPa (2,000 bar) and a temperature range of about 40°C to about 65°C and above is provided by the system illustrated in Figures 2 and 3. The system is not limited to dairy products or the temperatures mentioned above. As discussed previously, the system as described can be used for pressure-assisted temperature sterilization (PATS) or temperature-assisted pressure sterilization (TAPS). For example, the system can use operating temperatures of at least 130°C or higher in both applications. Sterilization utilizes high temperatures and pressures, which can reach 800,000 kPa (8,000 bar) or even higher. In one mode, controller 314 monitors one or more of the inlet water temperatures to the pressure vessel 326, calculates the system's adiabatic temperature rise, monitors the oil temperature in the oil-filled thermal insulation 324, and can also monitor the room temperature. To calculate the adiabatic temperature rise, controller 314 includes a program module. This module can utilize, for example, the specific heat capacities of the pressure medium (water) and metals, a calculated volume of metal in contact with the pressure medium, the ambient temperature, and the product temperature. The adiabatic temperature rise can also be pre-calculated and stored in a table accessible to controller 314. This table can be based on empirical data and / or actual measurements. Furthermore, in one mode, the temperature of the final product can also be part of the feedback loop, meaning that temperature adjustments are made based on the "quality" of the food. In one embodiment, the temperature increase or decrease can be precisely adjusted by means of the oil-filled thermal insulation 324, where the temperature can be raised or lowered as needed to maintain the temperature parameters. The temperature increase or decrease of the thermal insulation 324 is preferably achieved by means of temperature-controlled oil circulating between the wire-wound pressure vessel 326 and the interior of the vessel's foil cover. Although the thermal insulation 324 is described as using oil, this description is not limited to oil. In some embodiments, any heat transfer medium can be used within the vacuum of the thermal insulation 324. Multiple 322a-n thermocouples (or other temperature sensors) will be used to collect temperature data at different locations for use within the control / feedback loop to adjust temperature parameters at selected locations. The location selection is merely representative of one modality, and fewer or more temperature sensors may be used at other locations. Referring to Figure 2, an example of the designation of temperature sensors is shown below. This list is not intended to be exhaustive. The number of temperature sensors may be higher or lower depending on the specific application. 322a - temperature of the pressure medium in the water module 312. 322b - temperature of the pressure medium after the high pressure pump 310. 322c - temperature of the pressure medium to the pressure vessel 326. 322d - temperature of the pressure medium to the pressure vessel 326. 322e - temperature inside the pressure vessel 326. 322f - temperature inside the pressure vessel 326. 322g - thermal insulation temperature 324. 322h - pressure vessel wall temperature 326. 322i - oil temperature. 322j - return oil temperature of the thermal insulation 324. 322k - temperature of the pressure media of the 316 heat exchanger. 322I - measuring the temperature of food packages entering pressure vessel 326. 322m - measuring the temperature of food packages coming out of the pressure vessel 326. 322n - temperature measurement of pressurized food products or packages. Regarding the food product itself, temperature measurements can be taken using sensors in contact with the food, but also with other types of sensors, such as thermal imaging or infrared cameras. Consequently, the temperature of food entering and exiting pressure vessel 326 can also be recorded using temperature sensors. A control / feedback loop can measure one or more of the temperatures listed above to control the same temperature or a temperature at a different location. For example, both the pressure medium temperature and the oil temperature affect the temperature inside pressure vessel 326. In one example, a control / feedback loop includes temperature data such as the incoming water temperature (temperature sensor 322a) to the high-pressure pump 310, outgoing water temperature (temperature sensor 322b) from the high-pressure pump 310, incoming water temperature (temperature sensors 322c, d) to pressure vessel 326, the temperature (temperature sensors 322e, f) inside pressure vessel 326, the vessel wall temperature (temperature sensor 322h), and the temperature of the thermal insulation (temperature sensor 322g). In other modalities, the same or different locations can be used to measure the temperature. In one configuration, to minimize any temperature drop from the 310 high-pressure pump to the 326 high-pressure vessel, the high-pressure piping can be insulated. With a controlled and limited temperature drop in the high-pressure piping, the temperature accuracy within the 326 pressure vessel will be increased. In one example, the oil temperature and the pressure medium (water) temperature are controlled by the control logic residing in the programmable logic controller 314. In one example, one or more of the temperature sensors 322a to 322n are used in feedback loop control of the oil and pressure medium temperatures. Figure 3 is a schematic illustration of a modality similar to the modality in Figure 2, with the differences indicated below. Similar components shown in Figures 2 and 3 are designated with the same component reference number. In FIGURE 3, the auxiliary oil heating / cooling block 332 is replaced with an electric resistance heater 328 connected to a heating layer 330. The heating layer 330 may include resistance elements as a means of providing heat. The heating layer 330 can be wrapped around the outer cylinder of the pressure vessel 326 to provide heat for maintaining the process temperature within a desired range. A temperature sensor 322 is provided either on or near the heating layer 330 to measure the temperature of the heating layer 330 for use in one or more control loops executed by the controller 314. In one embodiment, the oil-filled "vacuum" acting as thermal insulation 324 can be emptied of oil and replaced with insulation. Figures 2 and 3 are representative modalities to show at least one way of controlling the processing temperatures of pressure vessel 326 and its contents during pressurization and the concomitant adiabatic temperature rise. The modalities in Figures 2 and 3 are not the only way to heat the pressure vessel and its contents. Heating and cooling of pressure vessel 326 is not limited to the auxiliary oil, heating layer, and pressurized media. Other heat generation or cooling systems may be used, including, but not limited to, microwave or radio frequency systems, or even resistance heaters integrated into the pressure vessel for heating, while refrigeration systems, including compression, evaporation, and absorption systems, may be used for cooling.Typical refrigerants for mechanical compression systems use hydrofluorocarbons, chlorofluorocarbons, propylene, and similar substances, while evaporative and absorption systems may use ammonia and water. The 316 heat exchanger for heating the pressure media can also be supplemented or replaced with another form of heating or cooling, such as those mentioned in this document. As mentioned previously, in one embodiment, the incoming product in basket 102 or another container to be processed must have its temperature fully controlled to achieve repeatable and reproducible results. This is due to factors such as the large mass of the pressure vessel 326, the limited area for heat transfer, and so on. Therefore, the auxiliary oil heating and cooling 332 and the heating layer 330 can be considered secondary systems for adjusting or maintaining the desired temperature, as well as for preventing or minimizing heat loss from the pressure vessel 326. In another embodiment, since the pressure medium is located closer to the product within the pressure vessel 326, the temperature of the pressure medium will be used as the primary means of temperature control, such as raising or lowering the process and / or product temperatures. In one example, the 314 controller includes at least a processor and system memory. Depending on the exact configuration and type of 314 controller, the system memory may be volatile or non-volatile, such as read-only memory (ROM), random-access memory (RAM), EEPROM, flash memory, or similar memory technology. Those skilled in the art and others will recognize that system memory typically stores data and / or program modules that are immediately accessible and / or currently being processed by the processor. In this respect, the processor can serve as the computing center of the 314 controller by supporting the execution of programmed logic instructions. In one example, the 314 controller might include a network interface comprising one or more components for communicating with other devices over a network. As someone skilled in the subject will appreciate, the network interface might represent one or more of the wireless or physical communication interfaces described and illustrated above with respect to particular components of the 314 controller. In one example, the 314 controller also includes a storage medium. The storage medium can be volatile or non-volatile, removable or non-removable, implemented using any technology capable of storing information, such as, but not limited to, a hard disk drive, solid-state drive, CD-ROM, DVD or other disk storage, magnetic cassettes, magnetic tape, magnetic disk storage, and / or similar media. As used herein, the term “computer-readable media” includes volatile and non-volatile, removable and non-removable media implemented in any method or technology capable of storing information, such as computer-readable instructions, data structures, program modules, or other data. In this sense, system memory and storage media are merely examples of computer-readable media.A tangible, non-transient, computer-readable medium can be used to store instructions, which, when executed by the 314 controller, can perform steps such as receiving one or more temperatures from one or more locations from the high-pressure processing system; and heating or cooling the pressure media or the heat transfer media or both in response to one or more temperatures deviating from a temperature range, and other steps to implement temperature control described in this document. Suitable implementations of the 314 controller, system memory, communication bus, storage medium, and network interface are well-known and commercially available. For ease of illustration, and because they are not essential to understanding the claimed subject matter, Figures 2 and 3 do not show some of the typical components of many controllers. In this regard, the 314 controller may include input devices such as a keyboard, numeric keypad, mouse, microphone, touch input device, touchscreen, tablet, and / or similar devices. Such input devices may be connected to the 314 controller via wired or wireless connections. In this disclosure, the 314 controller includes instructions embedded in hardware or software to perform certain steps. These instructions can be written in a programming language. The instructions can be compiled into executable programs or written in interpreted programming languages. The instructions can be stored on any type of computer-readable media or computer storage device and be stored and executed by the 314 controller, thereby creating a special-purpose computer configured to provide the functionality described herein. The 314 controller is used particularly to control the heating and cooling of oil and pressure media and / or to perform a sequence of steps based on feedback from one or more of the temperature sensors 322a through 322o. With reference to FIGURE 4, the main components of a temperature control system 400 for a high-pressure processing system are illustrated. The temperature control system 400, also shown in FIGURES 1, 2, and 3, includes at least one controller 402, as described herein, and a heating or cooling system 404 connected to affect the temperature of a high-pressure vessel 406. The heating or cooling system 404 is any system capable of adding or removing heat from the pressure vessel 406. The heater or cooler system 404 is in communication with the controller 402. Several heater and cooler systems were described in connection with FIGURES 2 and 3. However, FIGURE 4 is not limited to any particular heating or cooling system. Controller 402 is configured to control the heating or cooling system 404 to maintain a temperature of the pressure vessel 406 or a product therein in response to one or more temperatures deviating from a temperature range while the pressure vessel 406 is pressurized, and the corresponding adiabatic temperature increases. Controller 402 receives temperature signals via communication line 412 from the heating or cooling system 404 and temperature signals via communication line 414 from the pressure vessel 406 or its contents. The temperature signals are those produced by the temperature sensors described herein, such as temperature sensors 322a through 322o (see Figures 2 and 3), but may also include other temperature sensors from other locations. Controller 402 then uses the temperature signals to send an output via communication line 408 calculated to bring or maintain a temperature within a desired range. The temperature to be kept within a range may be the temperature of the heating or cooling system 404, the pressure vessel 406, or the contents of the pressure vessel. Some temperatures can be deduced; for example, if you want to control the temperature of a product, then it is not necessary to directly measure the temperature of the product, but you can deduce it by keeping other temperatures within the desired range. Controller 402 can send a signal, for example, to increase the flow rate of a heat transfer medium or coolant to pressure vessel 406, or to increase the current to an electric resistance heater in pressure vessel 406. The heater or cooler system 404 responds by adding heat to pressure vessel 406 or removing heat from pressure vessel 406, which also affects the temperature of the product itself. A temperature-controlled, high-pressure processing system like the one described can have advantages. In one embodiment, the high-pressure processing system eliminates the influence of ambient temperature on high-pressure dairy processing by using thermal insulation that can be used to heat or cool the pressure vessel to maintain processing temperatures within a range. In one mode, the high-pressure processing system controls the temperature of the pressure medium used for high-pressure pumping, and is adjusted and maintained within the determined temperature range to allow precise high-pressure processing of dairy products in the temperature range of approximately 45 to 65°C. In one embodiment, the temperature of the high-pressure vessel is controlled by means of an oil-filled thermal insulator that is heated or cooled to reach the processing temperatures. In one embodiment, the high-pressure processing system provides a method for precisely controlling the process temperature for dairy products by combining temperature data for the incoming and outgoing high-pressure media from the high-pressure pumps, the vessel wall temperature, as well as the temperature of the thermal insulation, and the adiabatic temperature rise. In one mode, the high-pressure processing system can analyze multiple temperatures from multiple locations within the high-pressure processing system and make temperature corrections, according to a programmed recipe. In one modality, the high-pressure processing system provides a method for minimizing process temperature tolerances through the use of control logic and built-in temperature sensors and measuring devices. Although illustrative modalities were shown and described, it will be appreciated that several changes can be made without departing from the spirit and scope of the invention.
Claims
NOVELTY OF THE INVENTION Having described the present invention as above, the following is considered novel and, therefore, is claimed as property: CLAIMS 1.A high-pressure processing system, characterized in that it comprises: a pressure vessel configured to receive a basket or container within the pressure vessel; a high-pressure pump configured to pump a pressure medium into the pressure vessel to increase the pressure within the pressure vessel; a controller configured to control a heating or cooling system to maintain a temperature of the pressure vessel or a product therein in response to one or more temperatures deviating from a temperature range while the pressure vessel is being pressurized; and an oil-filled thermal insulation containing an oil to reduce condensation, characterized in that an auxiliary heater / cooler is connected to the oil-filled thermal insulation to heat or cool the oil.
2. The high-pressure processing system according to claim 1, characterized in that it comprises thermal insulation, wherein the thermal insulation surrounds at least partially the pressure vessel, and the thermal insulation contains heat transfer means that are heated or cooled.
3. The high-pressure processing system according to claim 1, characterized in that it comprises a heat exchanger for heating and cooling the pressure media.
4. The high-pressure processing system according to claim 1, characterized in that it comprises an electrically heated heating layer surrounding the pressure vessel.
5. The high-pressure processing system according to claim 1, characterized in that the high-pressure pump can raise the pressure media to a pressure of at least 200000 kPa (2000 bar), or at least 400000 kPa (4000 bar), or at least 600000 kPa (6000 bar).
6. The high-pressure processing system according to claim 1, characterized in that it further comprises a controller having a non-transient, computer-readable tangible medium with instructions stored therein, which, when executed by the controller, performs the steps of: receiving one or more temperatures from one or more locations of the high-pressure processing system; and heating or cooling a pressure medium or a heat transfer medium or both in response to one or more temperatures deviating from a temperature range.
7. The high-pressure processing system according to claim 6, characterized in that the instructions further comprise performing the step of calculating the adiabatic temperature rise in the pressure media for a given pressure.
8. The high-pressure processing system according to claim 6, characterized in that the instructions further comprise performing the step of calculating the adiabatic temperature rise in the pressure vessel for a given pressure.
9. The high-pressure processing system according to claim 6, characterized in that the instructions further comprise performing the step of calculating the adiabatic temperature rise in a product for a given pressure.
10. The high-pressure processing system according to claim 6, characterized in that the temperatures are measured at one or more of the following locations: a temperature of the product to be processed, a temperature of the pressure medium before the high-pressure pump or pumps, a temperature of the pressure medium after the high-pressure pump or pumps, a temperature of the pressure medium at the pressure vessel, a temperature inside the pressure vessel, a temperature of thermal insulation, a temperature of a wall of the pressure vessel, a temperature of a heat transfer medium before the thermal insulation, a temperature of a heat transfer medium from the thermal insulation, a temperature of the pressure medium after a heat exchanger, a temperature of a room in which the high-pressure processing system is located,a temperature of a food or product entering the pressure vessel, a temperature of a food or product leaving the pressure vessel, and a temperature of a food or product when it is pressurized.
11. A method for high-pressure processing of a product in the high-pressure processing system according to claim 1, characterized in that it comprises: placing a container or basket with a product inside a pressure vessel; filling the pressure vessel with a pressure medium; increasing the pressure in the pressure vessel to at least 200,000 kPa (2,000 bar); and controlling a process or product temperature in the pressure vessel by keeping it above or below a temperature that results from an adiabatic temperature rise due to the pressure increase.
12. The method according to claim 11, characterized in that the adiabatic temperature rise is approximately 3 SC per 100000 kPa (1000 bar), and the process or product temperature is controlled to be above the adiabatic temperature rise.
13. The method according to claim 11, characterized in that the process or product temperature in the pressure vessel is controlled from approximately 40 SC to approximately 65 SC.
14. The method according to claim 11, characterized in that the product is a dairy product.
15. The method according to claim 11, characterized in that it further comprises, with a controller, calculating the adiabatic temperature rise of the pressure medium due to the pressure increase within the pressure vessel.
16. The method according to claim 11, characterized in that it further comprises, with a controller, calculating the adiabatic temperature increase inside the pressure vessel due to the pressure increase inside the pressure vessel.
17. The method according to claim 11, characterized in that it further comprises controlling a temperature of the pressure medium or a heat transfer medium in a thermal insulation surrounding the pressure vessel.
18. The method according to claim 11, characterized in that it further comprises controlling a temperature of a heating layer surrounding the pressure vessel.
19. The method according to claim 17, characterized in that the pressure medium and the heat transfer medium can be heated and cooled.
20. The method according to claim 11, characterized in that it further comprises measuring a temperature at one or more locations selected from the group consisting of: a temperature of the product to be processed, a temperature of the pressure medium before a high-pressure pump, a temperature of the pressure medium after the high-pressure pump, a temperature of the pressure medium to the pressure vessel, a temperature inside the pressure vessel, a temperature of the thermal insulation, a temperature of a wall of the pressure vessel, a temperature of the heat transfer medium before the thermal insulation, IVIA / a / ZUZZ / UI 1 »4 1 a temperature of the heat transfer medium from the thermal insulation, a temperature of the pressure medium after a heat exchanger, and a temperature of a room in which the pressure vessel is located,a temperature of a food or product entering the pressure vessel, a temperature of a food or product leaving the pressure vessel, and a temperature of a food or product when it is pressurized.
21. The method according to claim 11, characterized in that it further comprises maintaining the product at a high process pressure and temperature, according to a recipe stored in a controller.