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CN-121971888-A - Load balancing and switching control method and system for multi-column parallel radioactive separation

CN121971888ACN 121971888 ACN121971888 ACN 121971888ACN-121971888-A

Abstract

The invention relates to the technical field of radioactive separation control, and discloses a load balancing and switching control method and system for multi-column parallel radioactive separation, comprising the following steps of 1, collecting total activity of feeding, inlet pressure, outlet pressure, branch flow and outlet activity, and calculating health load capacity of homologous columns; step 2, determining a set of on-line working separation columns and target flow of each separation column, step 3, comparing a leakage ratio, a column pressure difference and a capacity utilization rate with corresponding thresholds, determining a trigger column and a main trigger column, step 4, determining relay columns and relay total steps, performing monotone relay adjustment on the main trigger column and the relay columns, step 5, checking the relay column state and completing column state switching, step 6, performing regeneration flushing and outlet activity self-checking on the separation columns in regeneration, and setting the qualified separation columns as spare, and step 7, performing the steps circularly and completing branch scheduling. The invention realizes the stable and continuous control of load balancing and switching process under the multi-column parallel radioactive separation system.

Inventors

  • GU LONG
  • Su Xingkang
  • WANG GUAN

Assignees

  • 福建睿斯科医疗技术有限公司

Dates

Publication Date
20260505
Application Date
20260408

Claims (10)

  1. 1. The load balancing and switching control method for multi-column parallel radioactive separation is characterized by comprising the following steps of: Step 1, collecting total activity, inlet pressure, outlet pressure, branch flow and outlet activity of a feed, determining column pressure difference and leakage ratio, updating accumulated consumption to obtain capacity utilization rate, and determining homologous column health load according to maximum allowable pressure difference and maximum allowable leakage ratio; step 2, determining an online working separation column set, and determining the target flow of each online working separation column based on the target health load and the homologous column health load; step 3, comparing the leakage ratio with a leakage early warning threshold value, comparing the column pressure difference with a pressure difference early warning threshold value, comparing the capacity utilization rate with a capacity threshold value to determine a trigger column, and determining a main trigger column; Step 4, determining a relay post and a relay total step number, and performing monotone relay adjustment on the target flow of the main trigger post and the relay post according to the relay total step number; step 5, verifying the leakage ratio and the column pressure difference of the relay column in the continuous verification cycle, and when the leakage ratio is lower than a leakage early warning threshold value and the column pressure difference is lower than a pressure difference early warning threshold value, setting the main trigger column in regeneration and setting the relay column to work on line; step 6, executing a first stage flushing time and a second stage flushing time on the regenerated separation column according to the regeneration flow, performing self-checking on the outlet activity by using a blank activity threshold value, and setting the separation column as a standby when the outlet activity is lower than the blank activity threshold value; and 7, circularly executing the steps 1 to 6 according to the control period duration, and completing data flow and control branch selection according to online work, standby, switching and regeneration.
  2. 2. The method for load balancing and switching control of multi-column parallel radioactive separation according to claim 1, wherein collecting the total activity of the feed, the inlet pressure, the outlet pressure, the branch flow and the outlet activity, determining the column pressure difference and the leakage ratio, updating the accumulated consumption to obtain the capacity utilization, and determining the health load of the homologous column according to the maximum allowable pressure difference and the maximum allowable leakage ratio, comprises: Step 11, collecting the total activity of the feed, the inlet pressure, the outlet pressure, the branch flow and the outlet activity of each separation column in each control period, determining the difference value of the inlet pressure and the outlet pressure as column pressure difference, taking the outlet activity as a molecule, taking the total activity of the feed as a denominator, and determining the ratio of the molecule to the denominator as leakage ratio; Step 12, taking the product of the total activity of the feed, the branch flow and the control period duration as an increment, adding the product with the accumulated consumption to update the accumulated consumption, taking the updated accumulated consumption as a numerator, taking the rated capacity as a denominator, determining the ratio of the numerator to the denominator as the capacity utilization rate, and taking one when the capacity utilization rate is larger than one; and 13, taking the column pressure difference as a numerator, taking the maximum allowable pressure difference as a denominator, determining the ratio of the numerator to the denominator as hydraulic stress, taking one when the hydraulic stress is larger than one, taking the leakage ratio as the numerator, determining the ratio of the numerator to the denominator as leakage risk, taking one when the leakage risk is larger than one, and determining the maximum value of the hydraulic stress, the leakage risk and the capacity utilization ratio as the health load capacity of the homologous column.
  3. 3. The method of load balancing and switching control for multi-column parallel radioactive separation of claim 1, wherein determining an online working separation column set, determining a target flow rate for each online working separation column based on a target health load and a homologous column health load, comprises: Step 21, obtaining column states of all separation columns in each control period, selecting the separation columns with the column states of on-line operation to form an on-line operation separation column set, and obtaining branch flow of all the separation columns in the on-line operation separation column set; Step 22, obtaining target health load capacity and homologous column health load capacity of each separation column in the online working separation column set, taking a difference value between the target health load capacity and the homologous column health load capacity as a loadable weight, and taking zero when the difference value is a negative value; And step 23, when the weight sum is greater than zero, the loadable weight of the single separation column is taken as a numerator, the weight sum is taken as a denominator, the ratio of the numerator to the denominator is determined as a split ratio, and the product of the split ratio and the total feed flow is determined as a target flow, when the weight sum is equal to zero, one is taken as the numerator, the number of separation columns in the on-line working separation column set is taken as the denominator, the ratio of the numerator to the denominator is determined as a split ratio, and the product of the split ratio and the total feed flow is determined as the target flow.
  4. 4. The method of load balancing and switching control for multi-column parallel radioactive separation of claim 1, wherein comparing the leak ratio to a leak pre-alarm threshold, comparing the column pressure difference to a pressure difference pre-alarm threshold, comparing the capacity utilization to a capacity threshold, determining a trigger column, and determining a primary trigger column, comprises: Step 31, determining an online working separation column set in each control period, and acquiring the leakage ratio, column pressure difference, capacity utilization rate and homologous column health load of each separation column in the online working separation column set, and simultaneously acquiring a leakage early warning threshold value, a pressure difference early warning threshold value and a capacity threshold value; Step 32, comparing the leakage ratio with a leakage early-warning threshold, comparing the column pressure difference with a pressure difference early-warning threshold, comparing the capacity utilization rate with a capacity threshold, and determining the corresponding separation column as a trigger column and forming a trigger column set when the leakage ratio is greater than or equal to the leakage early-warning threshold, or the column pressure difference is greater than or equal to the pressure difference early-warning threshold, or the capacity utilization rate is greater than or equal to the capacity threshold; step 33, when the trigger column set is not empty, selecting the trigger column with the largest health load capacity of the homologous column as a main trigger column according to the health load capacity of the homologous column, selecting the trigger column with the smallest number as the main trigger column when the health load capacity of the homologous column is the same, acquiring the target flow of the main trigger column, setting the main trigger column as in switching, and simultaneously solidifying the target flow of the main trigger column as the switching starting target flow.
  5. 5. The method for load balancing and switching control of multi-column parallel radioactive separation according to claim 1, wherein determining a relay column and a relay total step number, and monotonously adjusting a target flow rate of a main trigger column and the relay column according to the relay total step number, comprises: step 41, determining a standby separation column set according to column states in each control period, and acquiring homologous column health load of each separation column in the standby separation column set, wherein the standby separation column with the smallest homologous column health load is selected as a relay column, and the standby separation column with the smallest number is selected as the relay column when the homologous column health load is the same; step 42, obtaining the total relay step number, solidifying the total relay step number into the adjustment step number of the monotonic relay adjustment, obtaining the switching starting target flow of the main trigger column, and obtaining the target flow of the relay column as the starting target flow of the relay adjustment; step 43, updating the target flow in steps in the relay total step number, so that the target flow of the main trigger column is monotonically decreased in steps by taking the switching initial target flow as a reference, the target flow of the relay column is monotonically increased in steps by the amplitude equal to the decreasing amount of the target flow of the main trigger column, and the total feed flow of the online working separation column set is kept unchanged.
  6. 6. The method for load balancing and switching control of multi-column parallel radioactive separation of claim 1, wherein verifying the leakage ratio and the column pressure difference of the relay column in successive verification cycles, when the leakage ratio is lower than a leakage early warning threshold and the column pressure difference is lower than a pressure difference early warning threshold, placing the main trigger column in regeneration and placing the relay column in online operation comprises: Step 51, acquiring a continuous verification cycle number, determining a relay column as a verification object from the next control cycle after the completion of the relay total step number, and acquiring a leakage ratio, a column pressure difference, a leakage early warning threshold value and a pressure difference early warning threshold value of the relay column; Step 52, comparing the leakage ratio with a leakage early warning threshold value, comparing the column pressure difference with a pressure difference early warning threshold value, recording that the comprehensive verification passes when the leakage ratio is lower than the leakage early warning threshold value and the column pressure difference is lower than the pressure difference early warning threshold value, otherwise recording that the comprehensive verification does not pass, determining that the verification passes when the comprehensive verification passes in the continuous verification cycle number, otherwise determining that the verification does not pass; Step 53, when the verification is passed, the main trigger column is set to be regenerated, the relay column is set to be in online work, and the online work separation column set is updated, so that the main trigger column is removed from the online work separation column set, and the relay column is brought into the online work separation column set.
  7. 7. The method for load balancing and switching control of multi-column parallel radioactive separation of claim 6, further comprising, during the verification of the leak ratio and column pressure difference of the relay column for successive verification cycles: step 61, anchoring the starting point of the continuous verification cycle number as the next control cycle after the relay total step number is full, and keeping the relay column unchanged before the continuous verification cycle number is full; step 62, the main trigger column is not redetermined and the relay column is not redetermined in the continuous verification period number, and the main trigger column is kept in switching until verification is passed; And 63, when the continuous verification cycle number is full and verification passes, setting the main trigger column in regeneration and setting the relay column in online operation, and not setting the main trigger column in regeneration and not setting the relay column in online operation before the verification passes.
  8. 8. The method for load balancing and switching control of parallel radioactive separation of multiple columns according to claim 1, wherein the steps of performing a first stage flushing time and a second stage flushing time on the regenerating separation column according to the regeneration flow, and self-checking the outlet activity with a blank activity threshold, and setting the outlet activity to be standby when the outlet activity is lower than the blank activity threshold, comprise: step 71, obtaining a regeneration flow rate, a first stage flushing time, a second stage flushing time and a blank activity threshold value when the regenerating separation column enters regeneration, and keeping the regeneration flow rate, the first stage flushing time, the second stage flushing time and the blank activity threshold value unchanged during execution of the first stage flushing time and the second stage flushing time; Step 72, continuously executing the first-stage flushing time and the second-stage flushing time on the regenerated separation column according to the regeneration flow, and collecting the outlet activity of the regenerated separation column in the next control period after the second-stage flushing time is full; Step 73, comparing the outlet activity with a blank activity threshold, setting the regenerating separation column as standby when the outlet activity is lower than the blank activity threshold, and keeping the regenerating separation column as regenerating when the outlet activity is not lower than the blank activity threshold.
  9. 9. The method for load balancing and switching control of multi-column parallel radioactive separation according to claim 1, wherein steps 1 to 6 are cyclically executed according to control cycle duration, and data flow and control branch selection is completed according to on-line operation, standby, switching, and regeneration, comprising: Step 81, acquiring control period duration, and acquiring column states of all separation columns at the beginning of each control period by taking a period boundary of the control period duration as a trigger point of the steps 1 to 6; Step 82, grouping the separation columns into an online working separation column set, a standby separation column set, a switching separation column set and a regeneration separation column set according to column states at the beginning of each control period to obtain a grouping result, and solidifying the grouping result into a branch inlet object of the control period; Step 83, sequentially executing steps 1 to 5 on the on-line working separation column set and the switching separation column set in the present control period, executing step 6 on the regenerating separation column set, and writing the updated column state and the updated on-line working separation column set and the updated standby separation column set back as initial data of the next control period when the control period is over.
  10. 10. The load balancing and switching control system for multi-column parallel radioactive separation, which is characterized by adopting the load balancing and switching control method for multi-column parallel radioactive separation as claimed in any one of claims 1-9, comprising: the health quantity calculation module is used for collecting the total activity, inlet pressure, outlet pressure, branch flow and outlet activity of the feed, determining column pressure difference and leakage ratio, updating accumulated consumption to obtain capacity utilization rate, and determining homologous column health load according to the maximum allowable pressure difference and the maximum allowable leakage ratio; The target flow distribution module is used for determining an online working separation column set and determining the target flow of each online working separation column based on the target health load and the homologous column health load; Triggering a main column judging module, comparing the leakage ratio with a leakage early warning threshold value, comparing the column pressure difference with a pressure difference early warning threshold value, comparing the capacity utilization rate with a capacity threshold value to determine a trigger column, and determining a main trigger column; the monotone relay adjusting module is used for determining a relay column and a relay total step number, and monotone relay adjustment is carried out on the target flow of the main trigger column and the target flow of the relay column according to the relay total step number; the continuous verification switching module is used for verifying the leakage ratio and the column pressure difference of the relay column in the continuous verification period number, and when the leakage ratio is lower than a leakage early warning threshold value and the column pressure difference is lower than a pressure difference early warning threshold value, the main trigger column is set in regeneration and the relay column is set to work on line; The regeneration self-checking regression module is used for executing the first-stage flushing time and the second-stage flushing time on the regenerated separation column according to the regeneration flow, carrying out self-checking on the outlet activity by using a blank activity threshold value, and setting the outlet activity to be standby when the outlet activity is lower than the blank activity threshold value; and the periodic cycle scheduling module circularly executes each module according to the control period duration and completes data flow and control branch selection according to online work, standby, switching and regeneration.

Description

Load balancing and switching control method and system for multi-column parallel radioactive separation Technical Field The invention belongs to the technical field of radioactive separation control, and particularly relates to a load balancing and switching control method and system for multi-column parallel radioactive separation. Background The radioactive separation process is widely applied to the preparation of medical radionuclides and related fine chemical processes. With the increase of productivity and continuous operation requirements, the adoption of a mode of parallel connection of multiple separation columns has become an important means for improving processing capacity and system redundancy. Under the condition of multi-column parallel operation, unavoidable differences exist among the separation columns in the aspects of feeding activity, flow distribution, pressure loss, medium consumption and the like, if only fixed proportion diversion or manual experience adjustment is adopted, overload operation of individual separation columns is easy to cause, and other separation columns are insufficient in load, so that the reduction of separation efficiency, the increase of leakage risk or the advance entering of regeneration state are caused. In the prior art, a control mode of a multi-column parallel system generally processes load distribution, abnormality judgment and column switching respectively and independently, and lacks a unified state quantity as a control basis. In actual operation, load balancing is often simply distributed based on flow or time, and switching determination depends on single parameter or instantaneous threshold comparison, so that the load distribution basis is inconsistent with the switching trigger basis. When the pressure difference of a certain separation column is increased, the leakage is increased or the capacity is close to the limit, the system is difficult to transfer the load to other separation columns timely and smoothly, flow mutation or frequent switching is easy to generate, and continuous and stable operation of the system is influenced. In addition, the existing switching mode mostly adopts direct cutting or instantaneous switching, lacks transition regulation and verification processes, is easy to cause fluctuation of system working conditions under the condition of multi-column parallel connection, and even causes impact on downstream processes. The regenerated separation column is returned to standby or on line again, and a unified criterion connected with the preamble switching state is generally lacking, so that closed loop control is difficult to form. Disclosure of Invention The invention provides a load balancing and switching control method and a system for multi-column parallel radioactive separation, which solve the technical problem of insufficient operation stability caused by inconsistent load distribution basis and switching triggering basis and lack of smooth transition in the switching process under the multi-column parallel operation condition in the related technology. The invention provides a load balancing and switching control method for multi-column parallel radioactive separation, which comprises the following steps: Step 1, collecting total activity, inlet pressure, outlet pressure, branch flow and outlet activity of a feed, determining column pressure difference and leakage ratio, updating accumulated consumption to obtain capacity utilization rate, and determining homologous column health load according to maximum allowable pressure difference and maximum allowable leakage ratio; step 2, determining an online working separation column set, and determining the target flow of each online working separation column based on the target health load and the homologous column health load; step 3, comparing the leakage ratio with a leakage early warning threshold value, comparing the column pressure difference with a pressure difference early warning threshold value, comparing the capacity utilization rate with a capacity threshold value to determine a trigger column, and determining a main trigger column; Step 4, determining a relay post and a relay total step number, and performing monotone relay adjustment on the target flow of the main trigger post and the relay post according to the relay total step number; step 5, verifying the leakage ratio and the column pressure difference of the relay column in the continuous verification cycle, and when the leakage ratio is lower than a leakage early warning threshold value and the column pressure difference is lower than a pressure difference early warning threshold value, setting the main trigger column in regeneration and setting the relay column to work on line; step 6, executing a first stage flushing time and a second stage flushing time on the regenerated separation column according to the regeneration flow, performing self-checking on the outlet activity by using a blank activity