A plant essential oil fragrance fumigation production control system and method

Abstract

The application provides a plant essential oil fragrance smoking production control system and method, and relates to the technical field of plant essential oil production control, wherein the method comprises the following steps: acquiring the internal air pressure change value of an extraction device and the droplet interval duration of the condensate at the output end of a separation device; when the air pressure drops to the set lower limit and the interval duration shows an increasing trend, it is determined that the steam channel penetration phenomenon occurs, a pulse start-stop instruction is issued to the extraction device to alternately open and close the steam inlet valve, so as to reshape the internal plant material resistance distribution; the cumulative drainage value at the bottom of the separation device is acquired to calculate the internal residual water layer thickness; when the water layer thickness is lower than the set critical height, the drainage valve is controlled to continuously decrease the opening degree at the set attenuation ratio. The application improves the distribution of steam in the plant material and reduces the risk of essential oil diffusion in the drainage and separation link.

Description

Technical Field

[0001] This invention relates to the field of plant essential oil production control technology, and in particular to a plant essential oil aromatherapy production control system and method. Background Technology

[0002] Currently, the industrial extraction of plant essential oils for aromatherapy typically involves two main processes: steam distillation and static separation. In the actual production process, high-pressure steam supplied by an external pipeline is continuously fed into a sealed extraction vessel containing solid plant material. The steam penetrates the material bed, causing the volatile components inside to vaporize and release. The mixed gas carrying the target essential oil components then enters a cooling heat exchange pipeline, where it cools and transforms into a liquid oil-water mixture, which finally flows into a static separation vessel to await physical stratification.

[0003] During prolonged steam heat exchange, the plant material's moisture and volatiles are gradually stripped away. The solid material undergoes localized shrinkage after heating and dehydration, altering its original pore structure. The rising high-temperature fluid exhibits the physical characteristic of traveling along paths with minimal internal resistance, easily guiding steam to converge and accumulate in the enlarged pores, thus forming localized gas penetration channels within the plant material bed. When a large amount of steam rapidly penetrates these channels, the contact time and area between the gas and the material particle surface decrease, reducing the efficiency of heat and mass transfer and hindering the full extraction and release of essential oil components.

[0004] The condensed liquid mixture separates into an upper essential oil layer and a lower aqueous phase in a static separation container due to differences in physical density. Before obtaining the upper essential oil product, the drain valve needs to be opened to drain the lower aqueous phase through a pipe at the bottom of the container. In the latter part of the draining operation, as the overall water thickness inside the container decreases, the hydrostatic pressure on the water above the drain outlet decreases. If the drain valve remains open at the low liquid level, the radial flow of local fluid converging towards the bottom center accelerates, easily generating a hydraulic vortex with rotational angular momentum at the bottom of the container. The funnel-shaped drain vortex often extends upwards and disrupts the stable oil-water boundary layer, causing some of the separated essential oil to be carried downwards by the bottom water flow and discharged, resulting in physical dispersion loss of the target product. Summary of the Invention

[0005] The purpose of this invention is to provide a plant essential oil aromatherapy production control system and method to solve the technical problems in the existing plant essential oil steam extraction process, such as the solid plant material shrinking when heated to form internal through channels, causing steam to directly penetrate and affecting the uniformity of heat and mass transfer, and the subsequent static drainage and stratification, where the drop in liquid level easily triggers funnel-shaped hydraulic vortices, causing the upper essential oil to be carried away by the water flow at the bottom layer and lost.

[0006] In a first aspect, the present invention provides a plant essential oil aromatherapy production control system, including an extraction device, a condensation device, a separation device, and a main control device; the extraction device contains plant materials and is equipped with a steam inlet valve; the separation device is equipped with a drain valve; the extraction device is connected to the condensation device; the condensation device is connected to the separation device; and the main control device is communicatively connected to the extraction device, the condensation device, and the separation device respectively. The main control device is equipped with an anti-deviation control module and an anti-vortex control module. The anti-deviation control module acquires the gas pressure change value inside the extraction device and the droplet interval time of the condensate at the output end of the separation device during the extraction stage. When the gas pressure change value drops to a set lower limit and the droplet interval time shows an increasing trend, it is determined that a steam channel penetration phenomenon has occurred inside the extraction device. The main control device sends a pulse start-stop command to the extraction device to control the steam inlet valve configured in the extraction device to open and close alternately, so as to reshape the resistance distribution of plant materials inside the extraction device, ensure that the target essential oil components are fully extracted and transported to the separation device to form a sufficient and stable initial mixed fluid. In the subsequent separation stage, the anti-vortex control module obtains the cumulative drainage value at the bottom of the separation device based on the initial mixed fluid obtained under the action of the anti-deviation control module, and calculates the thickness of the remaining water layer inside the separation device based on the cumulative drainage value. When the thickness of the remaining water layer is lower than the set critical height, the drainage valve configured in the separation device is controlled to continuously reduce its opening according to the set attenuation ratio, so as to block the drainage vortex from entraining and losing the essential oil layer on the liquid surface.

[0007] Optionally, the extraction device further includes an extraction tank that carries the plant material; the bottom of the extraction tank is connected to the steam inlet valve, and the top of the extraction tank is connected to the exhaust valve; the main control device is electrically connected to the exhaust valve.

[0008] Optionally, the main control device has multiple preset standard extraction temperature ranges corresponding to different plant materials; during the normal extraction stage, the main control device controls the opening of the steam inlet valve to maintain the internal temperature of the refining tank within the standard extraction temperature range.

[0009] Optionally, the condensation equipment includes a coil condensation component and a circulating water pump that provides a cooling medium to the coil condensation component; the air inlet of the coil condensation component is connected to the exhaust valve; the main control equipment dynamically adjusts the operating frequency of the circulating water pump according to the real-time temperature of the steam output from the exhaust valve.

[0010] Optionally, the separation device includes an oil-water settling tank and a liquid level sensor located inside the oil-water settling tank; the liquid level sensor sends the detected initial mixed liquid level height value to the main control device for calculating the initial total internal volume parameters.

[0011] Optionally, the specific logic for the main control device to execute the pulse start / stop command includes: A closing command is issued to the steam inlet valve and a countdown timer for the fall is started, causing the plant material inside the extraction device to collapse naturally under the action of gravity, filling the local holes formed by the penetration of the steam channel; When the countdown timer reaches the set waiting time, a maximum opening command is sent to the steam inlet valve and the set impact time is maintained. The plant material is physically compacted by rapidly introduced high-pressure steam.

[0012] Optionally, before executing the pulse start / stop command, the main control device reads the temperature change rate of the condensate; if the droplet interval time shows an increasing trend and the temperature change rate shows a negative decreasing trend, the main control device determines that it is currently in the natural decay state at the end of the extraction period and prohibits the triggering path of the pulse start / stop command from being triggered.

[0013] Optionally, the anti-vortex control module uses a flow detector installed on the drain pipe of the separation equipment to calculate the cumulative drainage value in real time; the main control equipment obtains the total water volume calculated based on the initial total volume of the refining tank and the estimated essential oil volume, and subtracts the cumulative drainage value from the total water volume to obtain the internal remaining water volume; the internal remaining water volume is divided by the internal bottom area parameter of the separation equipment to calculate the thickness of the remaining water layer.

[0014] Optionally, the set critical height is a pre-tested physical threshold for vortex formation; when the thickness of the remaining water layer reaches the set critical height, the main control device continuously reduces the opening ratio of the drain valve according to the exponential decay model, and closes the drain valve before the thickness of the remaining water layer reaches zero.

[0015] Secondly, the present invention provides a method for controlling the production of plant essential oil aromatherapy products, applied to the plant essential oil aromatherapy production control system described in the first aspect, comprising the following control steps: During the extraction stage, the pressure change value inside the extraction device and the droplet interval time of the condensate at the output end of the separation device are obtained. When the gas pressure change value drops to a set lower limit and the droplet interval time shows an increasing trend, it is determined that a vapor channel penetration phenomenon has occurred inside the extraction device. A pulse start / stop command is sent to the extraction device to control the steam inlet valve configured in the extraction device to open and close alternately, so as to reshape the resistance distribution of plant materials inside the extraction device, ensure that the target essential oil components are fully extracted and transported to the separation device to form a sufficient and stable initial mixed fluid; In the subsequent separation stage, based on the initial mixed fluid, the cumulative drainage value at the bottom of the separation device is obtained, and the thickness of the remaining water layer inside the separation device is calculated based on the cumulative drainage value. When the thickness of the remaining water layer is lower than a set critical height, the drainage valve of the separation device is controlled to continuously reduce its opening according to a set attenuation ratio, so as to prevent the drainage vortex from entraining and losing the essential oil layer on the liquid surface. This invention achieves the following beneficial effects: This invention, by simultaneously acquiring the pressure changes inside the extraction device and the droplet interval at the condensate output, can accurately identify localized steam channel penetration within the plant material. Upon detecting this phenomenon, it sends pulse start / stop commands to the extraction device to alternately open and close the steam inlet valve. Utilizing the natural collapse of the material due to gravity after losing the upward lifting force of steam, and the subsequent instantaneous influx and compression of high-pressure steam, the spatial distribution of internal pore resistance in the material bed is reshaped. This improves the uniformity of subsequent contact between high-temperature steam and solid plant particles, ensuring stable heat and volatile component quality. The invention also utilizes accumulated drainage data to calculate the remaining water layer thickness at the bottom of the separation container in real time during the oil-water separation drainage stage. When the water layer thickness drops to a set critical height, the mechanical flow section opening of the drainage valve is actively and continuously reduced. This gradually reduces the centripetal kinetic energy of the bottom fluid converging towards the center of the drainage port in the later stage of drainage. From a fluid dynamics perspective, this blocks the dynamic conditions for the development of drainage vortex morphology, preventing the upper layer of stratified liquid essential oil from being swept downwards and discharged by the bottom vortex when it is about to be emptied. This balances the drainage efficiency of the lower water phase liquid with the integrity of the top essential oil product collection.

[0016] Other features and advantages of the invention will be set forth in the following description, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention may be realized and obtained by means of the structures particularly pointed out in the written description and the accompanying drawings.

[0017] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0018] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings: Figure 1This is a diagram showing the overall module connection relationship of the plant essential oil aromatherapy production control system in an embodiment of the present invention; Figure 2 This is a schematic diagram of the internal components of the extraction device, condensation device, and separation device in an embodiment of the present invention; Figure 3 This is a block diagram of the internal control module structure of the main control device in an embodiment of the present invention; Figure 4 This is a flowchart illustrating the anti-flow deviation control and steam channel penetration judgment logic in an embodiment of the present invention. Figure 5 This is a flowchart illustrating the logic of anti-vortex drainage control and water layer thickness calculation in an embodiment of the present invention. Figure 6 This is a flowchart illustrating the overall steps of the plant essential oil aromatherapy production control method in this embodiment of the invention. Detailed Implementation

[0019] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0020] like Figure 1 As shown in the figure, this application discloses a plant essential oil aromatherapy production control system, including an extraction device, a condensation device, a separation device, and a main control device; the extraction device contains plant materials and is equipped with a steam inlet valve; the separation device is equipped with a drain valve; the extraction device is connected to the condensation device; the condensation device is connected to the separation device; the main control device is communicatively connected to the extraction device, the condensation device, and the separation device respectively.

[0021] In this embodiment, combined with Figure 2A schematic diagram of the internal components shows that the extraction device is used to contain solid plant material in its initial state and provides a closed, pressurized heat exchange working space. It is understood that the extraction device includes an upright cylindrical body, a flange sealing cover at the top, a steam inlet at the bottom of the body, and an exhaust port at the top of the flange sealing cover. A high-temperature resistant sealing gasket is disposed between the body and the flange sealing cover. The exhaust port of the extraction device is connected to the air inlet node of the condensing device via an insulated conduit externally wrapped with aluminum silicate insulation material. The condensing device provides a cooling heat exchange interface with a temperature lower than the dew point parameter of the gaseous mixture, causing the gaseous mixture flowing into the extraction device to release its latent heat of phase change and convert into a liquid product. Further, the lower liquid outlet node of the condensing device is connected to the liquid inlet node of the separation device via a drainage pipe with a certain slope. The separation device provides a static space to contain the liquid fluid. The extraction device, the condensation device, and the separation device, which are physically connected in sequence through pipelines, constitute a fluid transport and phase change flow link for separating liquid essential oil components from solid plant materials.

[0022] In this embodiment, as Figure 3 As shown, the main control device is configured as a control unit that processes digital and analog signals from the field. It can be understood that the main control device includes a central processing unit module, an internal bus, a data storage module, a digital input module, a digital output module, an analog input module, and an analog output module. The main control device establishes electrical signal connections with the detection sensors and valve actuators arranged on the extraction device, the condensation device, and the separation device via industrial standard communication protocols. The main control device sends data reading commands to each detection sensor according to a set scanning cycle, and performs analog-to-digital conversion on the standard 4-20 mA current signals or 0-10 volt voltage signals returned by each detection sensor, processing them into floating-point engineering values ​​with corresponding physical dimensions. The main control device synchronously acquires fluid state data and actuator displacement feedback data distributed at each process node, providing a data source for executing subsequent logical comparisons and linkage control strategies.

[0023] In this embodiment, the main control device is equipped with an anti-deviation control module and an anti-vortex control module; see reference Figure 4The flowchart of the anti-flow deviation control logic shows that the anti-flow deviation control module acquires the pressure change value inside the extraction device and the droplet interval of the condensate at the output of the separation device during the extraction stage. Specifically, a diaphragm pressure transmitter is installed in the top gas chamber area of ​​the extraction device. The diaphragm pressure transmitter converts the sensed static absolute pressure inside the extraction device into an analog electrical signal. The anti-flow deviation control module continuously reads the instantaneous pressure scalar value fed back by the diaphragm pressure transmitter through the analog input module at a set millisecond sampling clock cycle. The anti-flow deviation control module constructs a fixed-length historical pressure scalar value buffer queue in a designated address segment of the data storage module. Whenever a new instantaneous pressure scalar value is acquired, the anti-flow deviation control module follows the first-in, first-out principle, writing the new instantaneous pressure scalar value to the tail of the historical pressure scalar value buffer queue and removing the oldest historical scalar value at the head of the queue. The anti-deviation control module invokes arithmetic operation instructions to calculate the arithmetic mean of all scalars in the current queue, and subtracts the arithmetic mean from the current instantaneous pressure scalar to obtain the pressure change value. Using a sliding window mean-subtraction data processing mode, the anti-deviation control module filters out conventional high-frequency pressure fluctuations caused by basic pulsations in the steam supply network, obtaining pressure change values ​​reflecting sudden changes in the fluid resistance of the plant material bed.

[0024] In this embodiment, a photoelectric detection component is installed on the vertical pipe section connecting the bottom of the condensation device and the separation device. It is understood that the photoelectric detection component includes an infrared emitting side and an infrared receiving side arranged opposite each other and coaxially. The infrared emitting side continuously emits an infrared beam of constant wavelength, which laterally passes through the gravity trajectory area of ​​the falling condensate inside the vertical pipe section. The anti-deviation control module monitors the digital level transition signal output by the infrared receiving side through a digital input module. When the condensate droplets begin to fall due to gravity overcoming surface tension, and their solid bodies penetrate the infrared beam, the infrared light is refracted or blocked by the droplets, causing a single falling edge transition in the digital level signal output by the infrared receiving side. The anti-deviation control module captures this falling edge transition event and reads the current system timestamp register value of the central processing unit.

[0025] Considering that industrial condensation terminals are often accompanied by trace amounts of uncondensed vapor escaping or tiny liquid mists sputtering, which can easily trigger false high-frequency level flips in the photoelectric detection component, the anti-bias control module activates a hardware time-domain mask window based on the droplet's physical gravity-driven droplet dynamics after capturing the first valid falling edge transition event and recording its timestamp. Specifically, the main control device defines the period from 50 to 80 milliseconds after recording this timestamp as a dead-zone shielding segment. This time span is calculated based on the shortest physical time required for a standard-sized essential oil-water mixture droplet (approximately 3mm to 5mm in diameter) to completely enter and exit the infrared beam's sensing diameter range due to gravitational acceleration. Within this dead-zone shielding segment, all subsequent edge transition pulses sensed by the photoelectric detection component are judged as optical sputtering scattering noise and ignored by the underlying driver program; only the next falling edge transition detected after exceeding this time-domain mask window is recognized as a completely new independent droplet event and a new timestamp is extracted. This processing step reconstructs the real discrete droplet trajectory of the physical droplet at the digital level, effectively eliminating the interference of stray optical noise on the timing measurement.

[0026] The anti-deviation control module subtracts the timestamp value recorded when the previous jump event occurred from the timestamp value corresponding to the current jump event to calculate the absolute time difference between the two discrete droplet drops, and obtains the droplet interval duration.

[0027] In this embodiment, the anti-dip flow control module performs trend determination logic operations on the acquired droplet interval durations. Specifically, the anti-dip flow control module collects multiple sequentially arranged droplet interval duration values ​​within a set time collection window, forming a two-dimensional analysis sample set including time and duration variables. The anti-dip flow control module calls the least squares algorithm module to perform linear regression fitting analysis on the values ​​in the analysis sample set and calculates the slope parameter of the regression line.

[0028] In this step, first-order linear regression fitting is chosen instead of higher-order polynomial fitting, based on a precise local micro-thermodynamic basis: in the initial physical stage when the steam channel has just penetrated, the proportion of high-temperature dry steam without water vapor entrainment flowing through the condenser suddenly increases, causing a transient decrease in the phase change yield. The phenomenon of increased condensate droplet spacing in the time domain approximately follows a linear local decay law of first-order Taylor expansion. The main control equipment only extracts data within the aforementioned short-time collection window for local linear fitting, avoiding the long-term mathematical lag that is easily caused by global complex nonlinear fitting. The calculated regression line slope parameter is directly equivalent in a physical sense to a first-order sensitivity index characterizing the decay of mass transfer rate in the initial stage of the sudden change in internal flow resistance of the material, thus strictly constraining the use of this algorithm within specific thermodynamic boundaries.

[0029] When the slope parameter of the calculated regression line is greater than zero and its absolute value exceeds the set deviation tolerance threshold, the anti-deviation control module outputs a high-level status flag to confirm and determine that the droplet interval time shows an increasing trend. The set deviation tolerance threshold is used to shield the occasional drop delay time fluctuations caused by slight differences in surface tension due to the accumulation of condensed droplets on the pipe wall.

[0030] Specifically, the physical calibration and acquisition methods of the aforementioned parameters include: the set time collection window length is configured to be 30 to 60 seconds to ensure that the sample set collects time samples of at least 20 discrete droplets; the set lower limit of the gas pressure change value, which characterizes the critical pressure drop at which the fluid resistance of the material bed is substantially lost, is obtained by the no-load resistance calibration method: when the extraction equipment is no-load and rated steam is introduced, the background absolute pressure drop at this time is measured, and the background pressure drop value is floated down by 10% to 15% as the set lower limit (its actual engineering value range is set between -1.5kPa and -3.5kPa); the deviation tolerance threshold (in units of seconds / drop) is established based on statistical control rules: when the extraction equipment is in the initial steady state stage without deviation, 50 droplet intervals are continuously collected and the standard deviation of the sample set is calculated, and three times the standard deviation is taken as the deviation tolerance threshold.

[0031] In this embodiment, when the gas pressure change value drops to a set lower limit and the droplet interval time shows an increasing trend, it is determined that a steam channel penetration phenomenon has occurred inside the extraction device. It can be understood that the set lower limit is a negative pressure threshold constant pre-configured in the data storage area of ​​the anti-deviation control module. When the plant material undergoes local shrinkage due to continuous heating, leading to pore expansion, the steam fluid follows the principle of the path of least resistance and concentrates towards the expanded pores, forming a physical channel penetrating the material layer, i.e., a steam channel penetration phenomenon occurs. When this phenomenon occurs, the steam directly penetrates the plant material layer, and the frictional resistance of the fluid through the material bed layer decreases, reducing the fluid pressure drop between the steam inlet and exhaust nodes of the extraction device. At this time, the anti-deviation control module executes a numerical comparison command to confirm that the gas pressure change value is lower than the set lower limit. Simultaneously, after the leaked high-temperature steam without extracted components enters the condensation device, because it does not carry the extracted plant moisture, the total amount of substances available for phase change condensation decreases, resulting in a decrease in the condensate yield collected at the end of the condensation pipe. At this time, the anti-deviation control module confirms that the droplet interval time shows an increasing trend. The anti-deviation control module uses a logical AND operation instruction. When the gas pressure drop characteristic, which represents a decrease in fluid pressure drop, and the droplet interval increase characteristic, which represents a decrease in phase change yield, are simultaneously established within the same judgment period, the anti-deviation control module triggers the confirmation logic flag bit of the steam channel penetration phenomenon and generates a fault alarm code.

[0032] In this embodiment, the main control device sends pulse start / stop commands to the extraction device, controlling the steam inlet valve configured in the extraction device to alternately open and close. This reshapes the resistance distribution of plant materials inside the extraction device, ensuring that the target essential oil components are fully extracted and transported to the separation device, forming a sufficient and stable initial mixed fluid. It is understood that after confirming steam channel penetration, the main control device interrupts the conventional proportional control program and sends a pulse control level sequence to the intelligent electric positioner controlling the steam inlet valve. When the pulse control level sequence is in a low-level period, the main control device sends a zero-opening drive signal through the analog output module, driving the actuator of the steam inlet valve to exhaust gas and perform a shut-off action. When the pulse control level sequence is in a high-level period, the main control device sends a full-scale drive signal, driving the steam inlet valve to perform a fully open action. In the closed state of the steam inlet valve, the high-speed steam flow transported upward from the bottom steam collection chamber is cut off. The plant material aggregate, losing the upward aerodynamic lifting force of the steam, naturally shifts and collapses towards the weaker structural support areas of the void channels under the influence of its own gravity. The closing action of the steam inlet valve alters the hydrodynamic boundary conditions, prompting the plant material to fill the abnormally enlarged pores within by its own weight.

[0033] Furthermore, the specific logical steps for the main control device to execute the pulse start / stop command include: issuing a closing command to the steam inlet valve and starting a fall countdown timer, causing the plant material inside the extraction device to naturally collapse under gravity, filling the local holes formed by the penetration of the steam channel; when the fall countdown timer reaches the set waiting time, issuing a maximum opening command to the steam inlet valve and maintaining the set impact time, using the rapidly introduced high-pressure steam to physically compact the plant material.

[0034] Specifically, the timer / counter module inside the main control device is configured as the fall countdown timer and loaded with the pulse count value corresponding to the set waiting time. The set waiting time is the time period reserved for the plant material to overcome the friction between particles and complete the downward displacement. When the count value of the fall countdown timer decreases to zero, the main control device sends a drive electrical signal to the steam inlet valve corresponding to the maximum opening. The steam inlet valve opens to the extreme value of the physical flow section, and saturated steam from the external steam supply network is introduced into the bottom space of the extraction device without throttling. Since the plant material after the collapse has covered the original pore area, the high-pressure steam forms a local high-pressure zone at the bottom interface of the plant material, generating an upward thrust and penetrating extrusion stress on the upper plant material cluster. During the time period limited by the set impact duration, the steam maintaining the maximum opening continuously physically compacts the plant material layer, reducing the microscopic pore structure between plant material particles. Once the set impact duration is reached, the main control device cancels the maximum opening command, the steam inlet valve exits the alternating opening and closing mode, restores the normal opening control parameters, and completes the reshaping of the spatial distribution of flow resistance of plant materials inside the extraction device.

[0035] Furthermore, to avoid over-compaction or under-collapse of materials due to improper setting of the duration parameter, the time parameter in the pulse start / stop command is dynamically solved based on the kinematics of the physical gravity field: the set waiting time According to the formula The calculation shows that, among which To determine the initial filling height of the plant material inside the refining tank, Let gravitational acceleration be constant. The coefficient of friction is an empirical frictional resistance coefficient based on the characteristics of plant debris (values ​​of 1.2 to 1.5 for foliage and flowers). This kinematic constraint ensures that the system provides sufficient and precise relaxation time, allowing the material to overcome interlayer static friction and complete free gravity collapse closure. The set impact duration is rigidly limited to a fixed time window of 2.0 to 4.5 seconds. This duration is calculated by dividing the volume of the bottom steam collection chamber by the saturated steam volume velocity when the steam inlet valve is fully open. The physical logic is to ensure that the rapidly introduced high-pressure steam can just create an effective upward local compressive stress at the bottom layer of the material, and cut off the command before it penetrates and destroys the newly closed material layer at the top, preventing a secondary blow-through effect.

[0036] In this embodiment, before executing the pulse start / stop command, the main control device reads the temperature change rate of the condensate. If the droplet interval duration shows an increasing trend, and the temperature change rate simultaneously shows a negative decreasing trend, the main control device determines that it is currently in the natural decay state at the end of the extraction process and prohibits triggering the trigger path of the pulse start / stop command. It is understood that when the distillation extraction process of plant essential oils enters its final stage, a large amount of volatile components in the plant material are stripped away, and the total amount of material transported to the condensing device with the steam decreases. This natural decay process also leads to a slowdown in droplet generation rate, manifested as an increasing trend in droplet interval duration. A platinum resistance thermometer is thermally coupled to the outer surface of the guide pipe discharged at the end of the condensing device using thermally conductive silicone grease. The main control device acquires the real-time absolute temperature data of the condensate transmitted by the platinum resistance thermometer at a fixed sampling period. The main control device calculates the temperature difference between two adjacent sampling period nodes and divides it by the sampling period time constant to obtain the temperature change rate parameter characterizing the slope of the temperature change. When steam passage penetration occurs, the pure high-temperature steam, without heat exchange, flows directly into the condenser, and the real-time temperature of the condensate does not decrease. The calculated temperature change rate parameter has a positive or zero algebraic sign. Conversely, in the natural decay state at the end of extraction, the total heat reaching the front end of the condenser decreases. Under the heat exchange effect of stable circulating cooling water, the output fluid temperature exhibits a continuous negative decreasing curve. If the main control device confirms that the droplet interval duration shows an increasing trend, and the numerical comparison logic determines that the temperature change rate parameter has a negative sign (i.e., a negative decreasing trend), then it is determined that the current process is in the natural decay state at the end of extraction. After obtaining this determination result, the main control device sets the pulse intervention enable position to an invalid state in the system status register. This invalid state flag prohibits triggering the pulse start / stop command trigger path at the program logic execution level and prohibits sending alternating start / stop drive signals to the steam inlet valve.

[0037] To ensure the integrity and process self-consistency of the control system in multi-batch continuous industrial production cycles, the main control equipment is further configured with a physical hardware reset interlock circuit for the aforementioned invalid state identifiers. Since the refining tank must be opened for slag removal and reloading after the current batch extraction is completed, the main control equipment monitors the status signal of the mechanical limit switch configured on the flange sealing cover at the top of the refining tank in real time via a digital input channel. Once the main control equipment detects that the flange sealing cover has been physically opened, causing the physical contacts of the limit switch to disconnect and jump, or that the diaphragm pressure transmitter detects that the internal absolute pressure has returned to zero and is depressurized, the main control equipment will immediately trigger a hardware-level reset interrupt command, clearing the pulse intervention enable bit in the system status register and resetting it to a valid, triggerable state. This reset logic rigidly interlocks the software algorithm's unlocking permission with the actual loading and unloading mechanical physical actions on-site, avoiding the potential for program control deadlock that can easily occur during continuous automated batch alternation from the bottom layer of the implementation chain.

[0038] In this embodiment, see Figure 5 The flowchart of the anti-vortex control logic shown illustrates that, in the subsequent separation stage, the anti-vortex control module, based on the initial mixed fluid obtained under the action of the anti-deviation flow control module, acquires the cumulative drainage value at the bottom of the separation equipment and calculates the thickness of the remaining water layer inside the separation equipment based on the cumulative drainage value. Specifically, an electromagnetic flow transmitter is flanged and connected to the horizontal section of the liquid discharge drainage conduit at the bottom of the separation equipment. The electromagnetic flow transmitter utilizes Faraday's principle of electromagnetic induction to measure the induced electromotive force generated by the conductive aqueous phase fluid cutting the alternating magnetic field and converts it into a digital signal of the instantaneous volumetric flow rate of the discharged liquid. The anti-vortex control module receives continuous digital signals of the instantaneous volumetric flow rate of the discharged liquid via a bus. The anti-vortex control module calls a definite integral operation subroutine within the central processing unit. The definite integral operation subroutine uses the opening moment of the discharge valve as the starting zero point of the time integration and the clock cycle of the main control equipment as the discrete step length, multiplying the instantaneous volumetric flow rate variable of the discharged liquid by the discrete step length to calculate the volume of the discharge micro-element. The definite integral operation subroutine accumulates the drainage infinitesimal volume into a long integer accumulator register, accurately calculates the total volume of fluid discharged from the start of drainage to the current time, and obtains the cumulative drainage value.

[0039] Since the discharge of liquid from the separation equipment is usually a long and slow discharge process, in order to overcome the serious truncation and accumulation error that is easily generated by the main control equipment in the tens of millions of small floating-point number accumulation operations, and to ensure the accuracy of the residual water layer thickness benchmark required for anti-vortex control, the discrete step length in the definite integral operation subroutine is synchronously configured by hardware to be the actual physical refresh cycle of the excitation alternating magnetic field inside the electromagnetic flow transmitter, specifically fixed within a discrete physical range of 100 milliseconds to 250 milliseconds. At the same time, the underlying accumulation logic adopts the discrete complex trapezoidal quadrature algorithm to replace the conventional rectangular quadrature algorithm, replacing it with discrete complex trapezoidal quadrature logic: that is, the derivation method of the discharge micro-element volume of the current step length is: add the discharge instantaneous volume flow rate read at the current moment to the discharge instantaneous volume flow rate recorded in the previous discrete step length, divide by two, and then multiply by the hardware discrete step length.

[0040] Further, the main control device subtracts the cumulative drainage value from the pre-acquired total water volume value to obtain the internal remaining water volume value; the internal remaining water volume value is then divided by the internal bottom area parameter of the separation device to calculate the remaining water layer thickness. It is understood that the main control device's non-volatile data memory pre-stores the total water volume value variable for the current batch and the internal bottom area parameter constant corresponding to the physical dimensions of the separation device. The anti-vortex control module executes a subtraction operation instruction, using the total water volume value as the minuend and the dynamically refreshed cumulative drainage value as the subtrahend, to calculate the internal remaining water volume value representing the volume of the retained water phase inside the current separation device container. Subsequently, the anti-vortex control module executes a division operation instruction, dividing the internal remaining water volume value by the internal bottom area parameter constant to obtain a spatial scalar with a single length dimension, i.e., calculating the remaining water layer thickness parameter reflecting the vertical coordinates of the liquid surface. This data processing process converts the volumetric flow rate data acquired by the flow velocity sensor into liquid surface height coordinates for subsequent control parameter comparison.

[0041] In this embodiment, when the thickness of the remaining water layer is lower than a set critical height, the opening of the drain valve configured in the separation device is continuously reduced according to a set attenuation ratio to prevent the drain vortex from entraining and losing the essential oil layer on the liquid surface. It is understood that the set critical height is a liquid level height threshold pre-input and stored in the parameter configuration table of the main control device. During the bottom drainage process of the separation device, when the liquid level drops, causing the thickness of the remaining water layer to decrease, the hydrostatic pressure of the fluid above the drain port decreases. When the thickness drops to a specific range, the radial centripetal acceleration of the fluid converging towards the center of the drain port increases significantly, thereby triggering fluid rotation and potentially forming a funnel-shaped drainage vortex that extends to the top interface. The drain valve configured at the bottom of the separation device is a proportionally adjustable shut-off valve assembly equipped with a high-resolution pneumatic or electric positioner. The anti-vortex control module uses a numerical comparator to frequently compare the currently calculated thickness of the remaining water layer with the set critical height parameter according to the processing cycle. When the thickness of the remaining water layer is greater than the set critical height, the anti-vortex control module outputs a constant analog control signal to the positioner of the drain valve to maintain the set drainage opening.

[0042] Furthermore, when the remaining water layer thickness reaches the set critical height, the main control device continuously reduces the opening ratio of the drain valve according to the exponential decay model, and closes the drain valve before the remaining water layer thickness reaches zero. Specifically, when the numerical comparator confirms that the value of the remaining water layer thickness is equal to or less than the value of the set critical height, the anti-vortex control module activates the opening decay execution program. The anti-vortex control module calls the internally stored nonlinear exponential decay mathematical function model. This model uses the continuously decreasing value of the remaining water layer thickness as the independent variable input, and calculates and generates a target valve core opening command dependent variable value exhibiting an exponentially decreasing characteristic. The anti-vortex control module converts the calculated target valve core opening command into a corresponding control current or voltage signal, and continuously sends it to the drain valve.

[0043] Specifically, to ensure that the anti-vortex control conforms to the fluid discharge pattern in the pipeline, the set critical height Based on the critical submersion depth law established by fluid dynamics, its geometric value is calibrated to be 1.5 to 2.0 times the physical inner diameter of the drainage conduit of the separation equipment. When the liquid level falls into this height range, the radial centripetal velocity of the fluid surges, creating the physical conditions for inducing a vortex that penetrates the liquid surface. The specific algebraic expression of the nonlinear exponential decay mathematical function model is defined as follows: In the formula, This is a dynamically calculated command for the target valve core opening percentage. The initial opening ratio constant of the drain valve when the remaining water layer thickness just reaches the set critical height; The thickness of the remaining water layer is the independent variable calculated by real-time definite integral. It is a natural constant; The discharge damping control coefficient is empirically limited to a value between 2.0 and 3.5. This physical equation establishes an exponential mathematical relationship between the spatial scalar of liquid level thickness and the contraction rate of the valve core's mechanical orifice, initially gradual and then rapid. By significantly increasing local hydraulic resistance, it effectively counteracts the microscopic angular momentum required for fluid vortex development. Furthermore, the preset near-zero point offset range is explicitly set as a physical dead zone isolation zone of 3 mm to 5 mm from the liquid surface to the bottom of the container. When the measured thickness falls into this range, the system immediately closes the drain valve, thus accommodating the cumulative error of minute definite integrals and effectively preventing mechanical entrainment and loss of the pure essential oil boundary layer.

[0044] As the control signal attenuates, the mechanical flow orifice of the drain valve continuously shrinks, leading to an increase in local fluid resistance in the drain pipe and forcing a reduction in the average volumetric flow velocity of the liquid discharged from the separation device. This decrease in flow velocity reduces the kinetic energy of fluid particles converging towards the center of the drain outlet, removing the angular momentum necessary for the development of the funnel-shaped vortex microstructure. The fluid at the bottom of the separation device is discharged slowly at extremely low velocity, and the oil-water interface at the top shifts downwards as a whole. The anti-vortex control module continuously monitors the calculated thickness of the remaining water layer. When this value falls into a preset near-zero offset range, the anti-vortex control module issues a zero-opening command, closing the drain valve and ending the drainage process.

[0045] In this embodiment, the extraction equipment further includes an extraction tank that carries the plant material; the bottom of the extraction tank is connected to the steam inlet valve, and the top of the extraction tank is connected to the exhaust valve; the main control device is electrically connected to the exhaust valve. It is understood that the extraction tank is a metal structure container whose main body bears the internal working pressure, and a porous metal steam distribution baffle assembly is laterally connected across the lower part of the inner cavity. Solid plant material is evenly distributed and filled above the porous steam distribution baffle assembly. The steam inlet valve is connected and installed between the external steam supply pipeline and the steam collection chamber at the bottom of the extraction tank. After passing through the steam inlet valve, steam evenly permeates into the plant material layer through the porous gaps of the steam distribution baffle assembly. The top of the extraction tank converges to form a mixed gas collection space. The exhaust valve is connected and installed on the discharge outlet pipeline of the mixed gas collection space. The exhaust valve is an industrial-grade pneumatic proportional control regulating valve equipped with an electronically controlled servo positioner. The main control device establishes an electrical signal transmission connection with the electronically controlled servo positioner of the exhaust valve through a signal cable, and controls the emission rate of the gas inside the refining tank to the condensation equipment by issuing opening command signals.

[0046] In this embodiment, the main control device has multiple preset standard extraction temperature ranges corresponding to different plant materials. During the normal extraction phase, the main control device controls the opening of the steam inlet valve to maintain the internal temperature of the refining tank within the standard extraction temperature range. It is understood that a lookup mapping data table is established within the non-volatile data storage area of ​​the main control device. This data table stores index coding sequences representing various plant material types, as well as upper and lower threshold parameters of the standard extraction temperature range corresponding to each index coding sequence. Temperature sensing probes are inserted and arranged on the wall of the refining tank. The main control device acquires the real-time absolute temperature data inside the refining tank measured by the temperature sensing probes through an analog input channel. The main control device calls a proportional-integral-derivative (PID) closed-loop negative feedback control algorithm module. The closed-loop negative feedback control algorithm module compares the real-time absolute temperature data with the currently called standard extraction temperature range set center constant value to obtain the temperature deviation error, and calculates the opening adjustment control quantity applied to the steam inlet valve positioner by combining the set proportional, integral, and derivative coefficients. When the real-time absolute temperature data is lower than the lower threshold of the standard extraction temperature range, the main control device controls the steam inlet valve to increase the flow cross-sectional diameter; when the real-time absolute temperature data approaches the upper threshold of the standard extraction temperature range, the main control device instructs the steam inlet valve to reduce the flow cross-sectional diameter, thereby limiting the fluid temperature inside the refining tank to within the standard extraction temperature range by adjusting the total enthalpy physical input.

[0047] In this embodiment, the condensation equipment includes a coil condenser component and a circulating water pump that provides cooling medium to the coil condenser component; the air inlet of the coil condenser component is connected to the exhaust valve; the main control device dynamically adjusts the operating frequency of the circulating water pump according to the real-time temperature of the steam output from the exhaust valve. It is understood that the coil condenser component has a metal heat-conducting tube bundle arranged inside and a pressure-bearing shell container for containing the circulating liquid cooling medium outside. The fluid outlet of the exhaust valve is connected to the fluid inlet channel of the metal heat-conducting tube bundle. The circulating water pump is connected to the shell via a pipeline and pumps liquid water into the shell cavity. The main control device is connected to a temperature sensor attached to the pipe wall on the output side of the exhaust valve to read the real-time temperature value of the exhaust steam at high frequency. An AC variable frequency speed controller is connected in series on the three-phase power supply circuit of the circulating water pump motor. The main control device is internally configured with a nonlinear frequency conversion function for cooling control. The main control device uses the read real-time temperature value as an input variable, substitutes it into the function, calculates the corresponding stator frequency command parameters, and sends them to the AC variable frequency speed controller via a communication bus.

[0048] Furthermore, to prevent logical misjudgments caused by minor disturbances in external operating conditions, the main control equipment establishes a threshold for determining whether the temperature change rate synchronously exhibits a negative decreasing trend. This threshold is quantified as follows: the temperature change rate is continuously monitored for at least three sampling cycles, all of which are negative, and the absolute value of the cooling slope in each sampling cycle is greater than the set attenuation benchmark value (0.05℃ / s). Regarding the nonlinear frequency conversion function for cooling control, considering the process constraint that plant essential oils are prone to solid-phase precipitation of high-melting-point wax components during overcooling, thus blocking the heat exchange coil, this function uses a nonlinear model instead of the conventional linear proportional PID model, which is prone to overshoot and overcooling. It is preset as a quadratic parabolic algebraic formula with an anti-overcooling buffer lower limit: In the formula, This refers to the stator frequency command issued to the frequency converter driver. This refers to the maximum rated operating frequency of the circulating water pump drive motor. To maintain the protection frequency limit (calibrated to 15Hz) for continuous heat exchange in the cooling water network foundation. The absolute temperature of the exhaust gas is read in real time; The preset minimum constant for process safety and anti-condensation temperature; This is the upper limit constant of the exhaust temperature under full load. Under this parabolic constraint mapping, as the exhaust enthalpy gradually approaches the critical value of the lower safety limit at the end of the extraction period, the cooling water pump's deceleration gradient adaptively converges and slows down, preserving ample flexible heat exchange buffer margin, thus avoiding in-tube crystallization failure caused by a sharp drop in temperature from the physical mechanism of the execution unit.

[0049] When the exhaust temperature rises, the main control device instructs the AC variable frequency drive to increase the stator output frequency, thereby accelerating the rotation speed of the circulating water pump and increasing the circulation flow rate of the cooling medium within the casing. When the exhaust temperature decreases, the main control device controls the AC variable frequency drive to decrease the stator output frequency, slowing down the rotation speed of the circulating water pump and reducing the circulation flow rate of the cooling medium. This linkage control maintains the temperature of the metal heat-conducting tube bundle contact wall above the set safe lower limit range when dealing with a decrease in heat exchange load, preventing the condensation and precipitation of solid phases of fluid components due to overcooling.

[0050] In this embodiment, the separation device includes an oil-water settling tank and a level sensor located inside the tank. The level sensor transmits the detected initial mixed liquid level height to the main control device for calculating the initial total internal volume parameters. It is understood that the oil-water settling tank is a vertical columnar pressure vessel with a uniform cross-sectional area. When the liquid product generated by the coil condenser stops being injected into the oil-water settling tank, and the fluid inside the separation device is in a settling stage, the level sensor, installed and fixed at the center of the top cover of the oil-water settling tank, is activated. The level sensor is a radar non-contact level detector. The level sensor emits a measurement microwave pulse sequence downwards toward the surface of the mixed fluid inside the container cavity. The microwave pulse sequence touches the fluid interface and generates a reflected echo. The level sensor measures the round-trip flight time of the pulse sequence and calculates the scalar vertical distance between the sensor probe reflector and the surface of the mixed liquid. The liquid level sensor calculates the geometric height of the mixed liquid surface from the bottom of the container by subtracting the vertical distance scalar from the pre-stored inner cavity depth constant of the oil-water settling tank, thus obtaining the initial mixed liquid level height value, which is then uploaded to the main control device via a digital bus. The main control device stores the geometric area constant parameter of the bottom surface of the oil-water settling tank in its storage area. The main control device extracts the received initial mixed liquid level height value and performs a multiplication operation with the geometric area constant parameter. The resulting product represents the total physical volume of the current batch of separated liquid substances. This total physical volume data is saved to the variable address data space and defined as the internal initial total volume parameter.

[0051] Since the initial total internal volume parameters obtained by the aforementioned radar detection actually include the mixed volume of the bottom stagnant water and the top liquid essential oil, to provide a pure aqueous phase data benchmark for subsequent anti-vortex definite integral calculations, the main control device pre-stores the initial total loading mass data of the current batch of extracted plants and the corresponding theoretical oil content constant (mass percentage) in its non-volatile storage area. The main control device calculates the estimated total essential oil mass by multiplying the initial total loading mass data by the theoretical oil content constant, and then divides it by the room temperature physical standard density constant of the essential oil to obtain the predicted physical volume of pure essential oil. Subsequently, the main control device executes a subtraction algebra instruction to subtract the predicted physical volume of pure essential oil from the initial total internal volume parameters, thereby calculating and separating the pure aqueous phase physical volume, which is directly assigned as the total water volume value.

[0052] Specifically, the present invention also provides a method for controlling the production of plant essential oil aromatherapy, applied to the plant essential oil aromatherapy production control system described in the above system embodiments, such as... Figure 6As shown, the control steps include the following, which are executed by the main control device in the system according to a set program logic sequence: Step S1: During the extraction stage, obtain the pressure change value inside the extraction device and the droplet interval of the condensate at the output end of the separation device.

[0053] During the data acquisition cycle, the underlying data processing driver of the main control device reads the analog voltage signal output by the pressure transmitter of the extraction device through the analog-to-digital conversion interface, performs a sliding time window queue operation, calculates the difference between the current pressure sample value and the queue mean, extracts the difference parameter reflecting the fluctuation characteristics of the fluid resistance in the material bed, and obtains the pressure change value. Simultaneously, the external interrupt handler of the main control device captures the level transition signal output by the photoelectric sensor at the input of the separation device, reads and saves the timestamp of the system clock register at the trigger moment, and obtains the droplet interval duration reflecting the production rate of the phase change system by calculating the time difference scalar between two adjacent valid trigger actions.

[0054] Step S2: Determine that a steam channel penetration phenomenon has occurred inside the extraction device.

[0055] The logic operation thread inside the main control unit extracts the gas pressure change value from the storage area and compares it with a pre-configured negative pressure drop lower limit constant. Simultaneously, the logic operation thread performs least-squares linear regression calculations on the droplet interval duration array stored in the cache sequence, obtains the fitting slope parameter, and determines its algebraic sign. Under the constraint that the comparison logic determines the gas pressure change value is less than the lower limit constant and the regression calculation logic determines the slope parameter is positive, both of which are simultaneously met within the same cycle, the main control unit establishes the diagnostic conclusion that a steam channel penetration phenomenon has occurred.

[0056] Step S3: Send a pulse start / stop command to the extraction device to control the steam inlet valve to open and close alternately, so as to reshape the material resistance distribution and ensure the formation of a sufficient and stable initial mixed fluid.

[0057] After confirming steam channel penetration, the main control unit's execution control thread writes a minimum control signal value to the steam inlet valve's positioner module, driving the valve to close and blocking steam kinetic energy input, causing the internal plant material to collapse and close into the pore area. When the set waiting time is reached, the execution control thread writes a maximum control signal value, actuating the steam inlet valve to its maximum flow cross-section. High-pressure steam then compresses and densifies the collapsed plant material bed. This alternating pulse reshaping process effectively eliminates flow deviation and alters the spatial resistance distribution structure of the plant material particles, ensuring sufficient heat exchange between the high-temperature steam and the plant material. This guarantees the full extraction of the target essential oil components, which are then continuously transported to the separation equipment with the condensate, thus forming a sufficient and stable initial mixed fluid, laying the physical foundation for subsequent separation operations.

[0058] Step S4: In the subsequent separation stage, based on the initial mixed fluid, obtain the cumulative drainage value at the bottom of the separation device and calculate the thickness of the remaining water layer.

[0059] In the settling and draining process of the separation equipment, the main control equipment first establishes the total water volume benchmark for the current batch based on the initial mixed fluid formed in the above steps. Subsequently, the integration thread of the main control equipment performs a definite integral accumulation calculation program on the volumetric flow rate scalar fed back by the flow transmitter in the drain pipeline according to the discrete step length, updates the total volume data of the drained fluid in real time, and obtains the cumulative drainage value. The algebraic operation thread of the main control equipment calls the established total water volume benchmark constant, subtracts the dynamically updated cumulative drainage value, obtains the volume value of the remaining water in the container, and divides it by the container bottom area parameter to obtain the remaining water layer thickness parameter reflecting the vertical coordinate system.

[0060] Step S5: When the thickness of the remaining water layer is lower than the set critical height, control the drainage valve to continuously reduce the opening according to the set attenuation ratio to block the runoff.

[0061] The comparator module of the main control equipment frequently compares the calculated value of the remaining water layer thickness with the set critical height within the parameter area. When it is confirmed that the remaining water layer thickness is equal to or less than the critical height, the main control equipment calls the preset nonlinear exponential function calculation module. This module uses the gradually decreasing remaining water layer thickness as an input variable, calculates and outputs the continuously shrinking opening adjustment target value in real time, and sends it to the drain valve. The continuous shrinkage of the valve orifice leads to an increase in local discharge resistance and a decrease in flow velocity, which gently reduces the centripetal kinetic energy of the bottom fluid converging towards the center. From a fluid dynamics perspective, it completely blocks the angular momentum conditions required for the development of the funnel-shaped drainage vortex, preventing the liquid surface oil layer from being swept downward by the bottom water flow. The valve is completely closed before the remaining water layer reaches zero, completing the production control closed loop.

[0062] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A plant essential oil aromatherapy production control system, comprising an extraction device, a condensation device, a separation device, and a main control device; the extraction device contains plant materials and is equipped with a steam inlet valve; the separation device is equipped with a drain valve; the extraction device is connected to the condensation device; the condensation device is connected to the separation device; the main control device is communicatively connected to the extraction device, the condensation device, and the separation device respectively; Its features are, The main control device is equipped with an anti-deviation control module and an anti-vortex control module. The anti-deviation control module acquires the gas pressure change value inside the extraction device and the droplet interval time of the condensate at the output end of the separation device during the extraction stage. When the gas pressure change value drops to a set lower limit and the droplet interval time shows an increasing trend, it is determined that a steam channel penetration phenomenon has occurred inside the extraction device. The main control device sends a pulse start-stop command to the extraction device to control the steam inlet valve configured in the extraction device to open and close alternately, so as to reshape the resistance distribution of plant materials inside the extraction device, ensure that the target essential oil components are fully extracted and transported to the separation device to form a sufficient and stable initial mixed fluid. In the subsequent separation stage, the anti-vortex control module obtains the cumulative drainage value at the bottom of the separation device based on the initial mixed fluid obtained under the action of the anti-deviation control module, and calculates the thickness of the remaining water layer inside the separation device based on the cumulative drainage value. When the thickness of the remaining water layer is lower than the set critical height, the drainage valve configured in the separation device is controlled to continuously reduce its opening according to the set attenuation ratio, so as to block the drainage vortex from entraining and losing the essential oil layer on the liquid surface.

2. The plant essential oil aromatherapy production control system according to claim 1, characterized in that, The extraction equipment also includes an extraction tank that holds the plant material; The bottom of the refining tank is connected to the steam inlet valve, and the top of the refining tank is connected to the exhaust valve; the main control equipment is electrically connected to the exhaust valve.

3. The plant essential oil aromatherapy production control system according to claim 2, characterized in that, The main control device has multiple preset standard extraction temperature ranges corresponding to different plant materials. During the normal extraction phase, the main control equipment controls the opening of the steam inlet valve to maintain the internal temperature of the refining tank within the standard extraction temperature range.

4. The plant essential oil aromatherapy production control system according to claim 3, characterized in that, The condensation equipment includes a coil condensation unit and a circulating water pump that provides cooling medium to the coil condensation unit; The air inlet of the coil condenser is connected to the exhaust valve; The main control equipment dynamically adjusts the operating frequency of the circulating water pump based on the real-time temperature of the steam output from the exhaust valve.

5. The plant essential oil aromatherapy production control system according to claim 4, characterized in that, The separation device includes an oil-water settling tank and a liquid level detection sensor located inside the oil-water settling tank. The liquid level detection sensor sends the detected initial mixed liquid level height value to the main control device for calculating the internal initial total volume parameters.

6. The plant essential oil aromatherapy production control system according to claim 1, characterized in that, The specific logic for the main control device to execute the pulse start / stop command includes: A closing command is issued to the steam inlet valve and a countdown timer for the fall is started, causing the plant material inside the extraction device to collapse naturally under the action of gravity, filling the local holes formed by the penetration of the steam channel; When the countdown timer reaches the set waiting time, a maximum opening command is sent to the steam inlet valve and the set impact time is maintained. The plant material is physically compacted by rapidly introduced high-pressure steam.

7. The plant essential oil aromatherapy production control system according to claim 6, characterized in that, Before executing the pulse start / stop command, the main control device reads the temperature change rate of the condensate; If the droplet interval duration shows an increasing trend and the temperature change rate shows a negative decreasing trend, the main control device determines that it is currently in the natural decay state at the end of the extraction period and prohibits the triggering path of the pulse start-stop command.

8. The plant essential oil aromatherapy production control system according to claim 1, characterized in that, The anti-vortex control module uses a flow detector installed on the drain pipe of the separation equipment to calculate the cumulative drainage value in real time. The main control device obtains the total water volume calculated based on the initial total volume of the refining tank and the estimated essential oil volume, and subtracts the cumulative drainage value from the total water volume to obtain the remaining water volume inside. The thickness of the remaining water layer is calculated by dividing the internal residual water volume by the internal bottom area parameter of the separation device.

9. The plant essential oil aromatherapy production control system according to claim 8, characterized in that, The set critical height is the physical threshold for vortex formation obtained from pre-testing; When the thickness of the remaining water layer reaches the set critical height, the main control device continuously reduces the opening ratio of the drain valve according to the exponential decay model, and closes the drain valve before the thickness of the remaining water layer reaches zero.

10. A method for controlling the production of plant essential oil aromatherapy, applied to the plant essential oil aromatherapy production control system described in claim 1, characterized in that, The following control steps are included: During the extraction stage, the pressure change value inside the extraction device and the droplet interval time of the condensate at the output end of the separation device are obtained. When the gas pressure change value drops to a set lower limit and the droplet interval time shows an increasing trend, it is determined that a vapor channel penetration phenomenon has occurred inside the extraction device. A pulse start / stop command is sent to the extraction device to control the steam inlet valve configured in the extraction device to open and close alternately, so as to reshape the resistance distribution of plant materials inside the extraction device, ensure that the target essential oil components are fully extracted and transported to the separation device to form a sufficient and stable initial mixed fluid; In the subsequent separation stage, based on the initial mixed fluid, the cumulative drainage value at the bottom of the separation device is obtained, and the thickness of the remaining water layer inside the separation device is calculated based on the cumulative drainage value. When the thickness of the remaining water layer is lower than the set critical height, the opening of the drain valve configured in the separation device is continuously reduced according to the set attenuation ratio to block the drain vortex from carrying away the essential oil layer on the liquid surface.

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