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CN-121977339-A - Porous instant coffee granule drying method

CN121977339ACN 121977339 ACN121977339 ACN 121977339ACN-121977339-A

Abstract

The invention discloses a porous instant coffee particle drying method, which relates to the technical field of food processing and drying equipment control, and is characterized in that a closed drying cavity and a carbon dioxide circulating gas circuit are controlled in a closed loop by a special drying process large model. The method comprises the steps of collecting various data on line and encoding the data into a working condition sequence, searching a process memory base by taking a control window as a unit to generate a candidate control mark sequence, carrying out forward-looking prediction by a micro twin predictor and outputting a prediction boundary crossing mark, generating a control mark sequence which allows execution by an executable compiler and outputting a forbidden execution reason code, carrying out consistency check and sensing consistency check by a checker, outputting a refusal execution mark and carrying out a safe degradation control mark when the consistency check and the sensing consistency check are abnormal, driving a carbon dioxide replacement by an execution interface, pore canal filling, periodical pressure swing, adsorbent bed switching, recharging intensity, dew point and temperature upper limit and volatile component maintenance control mark, triggering regeneration when the deviation is carried out, and completing closed discharging.

Inventors

  • SUN XIUFENG
  • KE XIANFU
  • Ye Qiaozhang
  • CHEN XINYU
  • DONG LIZHI
  • TAI YAO

Assignees

  • 云南巴莱咖啡有限公司

Dates

Publication Date
20260505
Application Date
20260224

Claims (10)

  1. 1. A porous instant coffee particle drying method is characterized by comprising the steps of arranging and controlling a closed drying cavity and a carbon dioxide circulating gas path in a closed loop by a special drying process large model, wherein S1 to S7 are carried out, S1 is carried out on porous instant coffee wet particles into the closed drying cavity and the carbon dioxide circulating gas path is started, working condition parameters are collected online and encoded into a working condition sequence updated with time, S2 is carried out on the basis of a control window by taking a control window as a unit, similar batch working condition fragments and corresponding control fragments in a process memory are searched on the basis of the working condition sequence, S3 is carried out on the cavity pressure track, the circulating gas dew point, the back pressure end point pressure satisfaction, the regeneration progress of a regenerated adsorption bed, the glassy stability and the tail gas volatile component concentration in the next control window under the driving of the candidate control mark sequence in a forward-looking mode and outputting a predicted out-of-bound mark, S4 is carried out on the candidate control mark sequence in an executable mode based on the working condition sequence and the predicted out-bound mark to generate a control mark sequence allowing to execute, and a control mark violating preset constraint is shielded and a control mark is output to prohibit execution code is carried out on the shielded control mark, S5 is carried out on the control sequence allowing execution and the control sequence is carried out in a consistent check mode, outputting a reject execution flag and triggering regeneration of the candidate control flag sequence when either check fails and outputting a safety degradation control flag and executing the safety degradation control flag during the reject execution flag' S existence to keep the carbon dioxide recycle gas path in communication and execute a recycle gas dew point upper limit control flag and pause a periodic pressure swing control flag; S6, after verification is passed, executing the control mark sequence which allows execution so as to drive the closed drying cavity and the carbon dioxide circulating gas channel to execute carbon dioxide replacement and pore canal filling, executing periodical pressure swing so that the pressure reduction stage triggers moisture flash evaporation in the pore canal, the back pressure stage provides pore wall gas support, executing adsorption state switching control marks and regeneration state switching control marks so that the regeneration window coincides with the pressure reduction stage in time and the same pressure reduction event provides low pressure conditions required by regeneration, simultaneously executing recharging intensity control marks so as to enable exothermic recharging of an adsorbent bed to the carbon dioxide circulating gas channel through a heat exchange recharging executing piece and execute a circulating gas dew point upper limit control mark and a circulating gas inlet temperature upper limit control mark so as to adjust the circulating gas state and execute volatile component holding control marks so as to limit the concentration of tail gas volatile components, and shielding the pressure reduction control mark of the next control window and only allowing safe degradation control marks, the circulating gas dew point upper limit control marks and the back pressure holding control marks until the regeneration of the ecology adsorbent bed is completed, S7, executing closed-loop tracking the control marks and rejecting deviation triggering marks when the tracking deviation from preset tolerance is deviated in the execution process so as to generate candidate marks, and executing an inerting cooling control mark after the working condition sequence meets the target water-containing termination condition and the glassy state stable termination condition, and discharging through a closed path.
  2. 2. The method of claim 1, wherein the dedicated drying process large model comprises a condition encoder, a process memory bank, a control flag vocabulary, a strategy generator, a micro-twin predictor, an executable compiler, a verifier and an execution interface, wherein the control flag is expressed in the form of a control flag vocabulary and defines a flag parameter field and a mapping relationship of the flag parameter field and a cavity pressure adjustment actuator, a depressurization, a back pressure hold, an adsorption state switch, a regeneration state switch, a bypass ratio, a recharging strength, a dew point upper limit, a recycle gas inlet temperature upper limit, a volatile component hold, an inerting cooling and a safety degradation as executable control flags corresponding to the equipment actuator, and wherein the control flag vocabulary defines a flag parameter field and a cavity pressure adjustment actuator, an adsorption bed switch actuator, a bypass valve set, a heat exchange recharging actuator, a dew point adjustment actuator and a vent gas discharge actuator, respectively, for depressurization, back pressure, a recharging strength, a dew point upper limit, a recycle gas inlet temperature upper limit and a volatile component hold within the execution interface.
  3. 3. The method according to claim 1, wherein the sensing consistency is performed by a verifier by consistency comparison of the oxygen content in the cavity with the oxygen content in the inlet of the carbon dioxide recycle gas path and defining a maximum absolute difference in the control window of no more than 0.5 volume percent, consistency comparison of the carbon dioxide recycle gas inlet dew point with the return gas dew point and defining a maximum absolute difference in the control window of no more than 3 degrees celsius, consistency comparison of surface water content state indexes respectively mapped by at least two acquisition channels of the near infrared reflectance spectrum of the particle surface under the same timestamp and defining a maximum absolute difference in the control window of no more than 0.10, consistency comparison of equivalent vitrification state indexes respectively mapped by at least two acquisition channels of the dielectric response of the particle layer under the same timestamp and defining a maximum absolute difference in the control window of no more than 0.10, and triggering rejection of execution of the security degradation control mark and the upper limit control mark of the recycle gas dew point only when either consistency comparison is not met.
  4. 4. The method of claim 2, wherein the micro-twin predictor generates a look-ahead prediction based on the sequence of conditions, the sequence of candidate control markers, and similar batch track segments in the process memory and outputs a prediction out-of-bound marker comprising a prediction out-of-bound type marker and a prediction out-of-bound time marker as trigger inputs for the executable compiler mask control marker.
  5. 5. The method of claim 1, wherein the volatile component holding constraint is defined by an upper end gas volatile component concentration limit and an upper end gas volatile component concentration change rate limit, wherein the upper end gas volatile component concentration limit is a preset value in a range of 0.1 milligrams per liter to 50 milligrams per liter and the upper end gas volatile component concentration change rate limit is a preset value in a range of 0.01 milligrams per liter per second to 10 milligrams per liter per second, and wherein the executable compiler masks a control flag corresponding to the increase in recharge strength and a control flag corresponding to the increase in the depressurization rate when the end gas volatile component concentration is not less than 80% of the upper end gas volatile component concentration limit or the upper end gas volatile component concentration change rate is not less than 80% of the upper end gas volatile component concentration change rate limit.
  6. 6. The method of claim 1, wherein the regeneration completion criteria is determined by a regeneration bed outlet dew point change rate, a regeneration bed outlet temperature change rate, a sustained satisfaction period, and a regeneration bed inlet dew point together, and wherein regeneration completion is determined by a regeneration condition encoder generating a regeneration completion status flag input executable compiler to maintain or unmask a next control window depressurization control flag when the regeneration bed outlet dew point change rate is not higher than 0.05 degrees celsius per second and the regeneration bed outlet temperature change rate is not higher than 0.05 degrees celsius per second for 30 seconds to 600 seconds and the regeneration bed inlet dew point is not higher than a preset inlet dew point upper limit.
  7. 7. The method of claim 1, wherein the glassy stability is generated by a condition encoder fusing a surface water content index of a particle surface near infrared reflectance spectrum map with an equivalent glassy state index of a particle layer dielectric response map and is defined as a dimensionless number in a range of 0 to 1, and wherein the executable compiler masks a control mark corresponding to a recharge intensity boost and a control mark corresponding to a dew point upper limit relaxation and a control mark corresponding to a backpressure endpoint pressure reduction when the glassy stability is below 0.30.
  8. 8. The method of claim 1, wherein the execution bias flag is generated by the execution interface based on a cavity pressure trace error, a dew point trace error, a cycle gas inlet temperature trace error, a back pressure endpoint pressure trace error, a bed state consistency error, an exhaust gas volatile component concentration trace error, and a particulate layer pressure drop bias and carries a bias source flag and a bias class flag, wherein the bed state consistency error is an error corresponding to a mismatch between a feedback state of the bed switch execution member and a target state given by the adsorption state switch control flag or the regeneration state switch control flag, and wherein the preset tolerance is defined as a cavity pressure trace error of no more than 5 kpa, a dew point trace error of no more than 2 degrees celsius, a cycle gas inlet temperature trace error of no more than 3 degrees celsius, a back pressure endpoint pressure trace error of no more than 5 kpa, and an exhaust gas volatile component concentration trace error of no more than 10% of the exhaust gas volatile component concentration upper limit, and the verifier selects to output a rejection flag based on the bias class flag and regenerates or outputs the safety control flag and executes the safety degradation control.
  9. 9. The method according to claim 1, wherein the process memory stores a working condition sequence, a control mark sequence, a forbidden execution reason code sequence, a predicted out-of-range mark sequence, an execution deviation mark sequence, a glassy stability track, a volatile component holding track and a termination condition achievement track with lots as indexes, and the strategy generator applies a negative search weight to a history control mark sequence including an adhesion sintering risk trigger track, a moisture regain risk trigger track, a volatile component holding constraint high frequency trigger track or an execution deviation mark high frequency trigger track to limit the generation space of the candidate control mark sequence when searching the process memory.
  10. 10. The method according to claim 1, wherein the inerting cooling defines that the carbon dioxide circulating gas dew point is not higher than the circulating gas dew point upper limit constraint and the pressure of the closed drying cavity is not lower than the back pressure hole wall supporting lower limit constraint corresponding to the pressure value in the cooling stage, and the discharging action is communicated with the packaging interface through the closed path, and the carbon dioxide circulating gas path is kept communicated in the discharging stage and the circulating gas dew point upper limit control label is executed, the working condition parameters comprise a cavity pressure track, a circulating gas dew point, a cavity oxygen content, a circulating gas inlet and outlet temperature, a particle layer pressure drop, a particle surface near infrared reflectance spectrum, a particle layer dielectric response and a tail gas volatile component concentration, and the candidate control label sequence comprises a carbon dioxide replacement control label, a pore channel filling control label, a periodical pressure swing control label, an adsorption state switching control label, a regeneration state switching control label, a bypass proportion control label, a recharging strength control label, a circulating gas dew point upper limit control label, a circulating gas inlet temperature upper limit control label, a volatile component maintaining control label, an inerting cooling control label and a safe degradation control label, and the preset constraint comprises a cavity pressure track, a dew point upper limit constraint, a pressure upper limit constraint, a back pressure supporting limit, a volatile component maintaining constraint and a stable constraint, a stable constraint of a stable constraint and a stable constraint of a regeneration source.

Description

Porous instant coffee granule drying method Technical Field The invention relates to the technical field of food processing and drying equipment control, in particular to a porous instant coffee particle drying method. Background The porous instant coffee particles generally have the characteristics of obvious pore structure, large specific surface area and sensitive change of water-containing state and temperature state, the drying process of the porous instant coffee particles not only needs to realize effective migration and removal of water, but also needs to avoid structural collapse, caking and adhesion, moisture regain and abnormal loss of aroma-related volatile components in the drying and cooling processes, and meanwhile, the engineering requirements of continuous production line, batch stability and traceable management are also met. In the prior art, hot air drying, vacuum drying, fluidization drying, freeze drying or a combination process thereof is generally adopted for drying instant coffee particles, and means such as circulating air dehumidification, temperature regulation and pressure regulation are matched to control the drying rate and the end water content level to a certain extent, but the technical route still has certain limitations, mainly comprises the following steps that the drying process has multiple working condition variables and strong coupling, unstable drying rate is easily caused by fluctuation of parameters such as cavity pressure, dew point, temperature and gas components, the particle water content and the structural state are distributed unevenly in space and time, the problems of stable pore structure and product appearance, agglomeration, adhesion, pulverization or partial overdry are easily caused in production due to single sensing quantity or small quantity of control quantity, when raw material fluctuation, equipment disturbance or abnormal sensing occurs, the control strategy often lacks an effective robust and executable checking mechanism, the consistency between batches is insufficient, the process is difficult, and in addition, under the condition that the condition of inert environment requirement, the circulating air dehumidification and the tail gas emission constraint coexist, the coordination ability of the traditional control mode to the multiple constraint conditions is easy, and the problem of smooth constraint strategy is not easy to conflict or not to appear. Therefore, there is a need for a porous instant coffee particle drying method that can achieve stable process control, improve batch consistency, and promote engineering applicability under multivariable, multi-constraint conditions. Disclosure of Invention The invention aims to overcome the defects of the prior art and provides a porous instant coffee particle drying method which aims to solve the problems. The invention aims at realizing the technical scheme that the porous instant coffee particle drying method comprises the following steps of arranging and closed-loop controlling a closed drying cavity and a carbon dioxide circulating gas channel by a special drying process big model, wherein S1 to S7 are carried out, S1 is carried out on porous instant coffee wet particles in the closed drying cavity and the carbon dioxide circulating gas channel is started, working condition parameters are collected online and encoded into a working condition sequence updated with time, S2 is carried out on the basis of a control window, candidate control mark sequences are generated on the basis of similar batch working condition fragments and corresponding control fragments in a process memory base in a control window unit, S3 is carried out on cavity pressure tracks, circulating gas dew points, back pressure end point pressure satisfaction, regeneration progress of a regenerated adsorption bed, glass state stability and tail gas volatile component concentration in the next control window under the driving of the candidate control mark sequences, and output prediction boundary crossing marks, S4 is carried out on the candidate control mark sequences on the basis of the working condition sequences and prediction boundary crossing marks to generate control mark sequences which are allowed to be executed, and a control code which is violated is forbidden to be executed on the basis of the control mark output to be blocked, S5 is carried out on the basis of preset control mark output to enable control sequences to be allowed to be executed, consistency check and the working condition sequences are carried out, outputting refusal execution mark and triggering regeneration candidate control mark sequence when any check is not passed and outputting safety degradation control mark and executing safety degradation control mark to keep carbon dioxide circulation gas path connected and execute circulation gas dew point upper limit control mark and pause periodic pressure swing control mark during refusal execution