An automatic product abundance control method under a material flow and material handling control mode

Abstract

This invention relates to the field of uranium isotope separation technology, specifically to an automatic product abundance control method under a material flow collection control mode, comprising the following steps: Step 1, setting control signals; Step 1.1, selecting control time points; Step 1.2, calculating the maximum abundance deviation; Step 1.3, setting control signals in segments; Step 2, control signal feedback; Step 3, calculating the collection pressure adjustment amount; Step 3.1, calculating the instantaneous abundance target value; Step 3.2, calculating the collection target control pressure; Step 4, adjusting the regulator control pressure. This invention provides a highly stable product abundance adjustment method, reducing the frequency and magnitude of pressure adjustments during the container collection stage, especially in the early stages of collection, resulting in a more stable product collection process.

Description

Technical Field

[0001] This invention relates to the field of uranium isotope separation technology, specifically to an automatic control method for product abundance under a material flow control mode. Background Technology

[0002] Currently, the production line controls the amount of material taken from the feed stream, thereby controlling the product intake. Excess material is fed back to the final stage of the concentrate supply, changing the final stage's intake ratio to adjust the online instantaneous product abundance (hereinafter referred to as instantaneous abundance). This ensures that the average abundance within the container (hereinafter referred to as bottled abundance) meets the product quality target. Under this method, product abundance control mainly involves two approaches:

[0003] Method 1 involves not controlling the bottled abundance in the early stages of material collection, but then significantly adjusting the collection control pressure in the later stages to bring the bottled abundance back within the controllable range. While this method can achieve the product quality target at the end of container collection, the greater the instantaneous abundance fluctuation during the collection process, the greater the loss of separation energy within the container.

[0004] Method 2: When the bottled abundance exceeds the set control range, the instantaneous abundance is gradually adjusted in steps of 0.01 kPa to bring the bottled abundance back to the center limit. This method will increase the frequency of adjustment of the instantaneous abundance of the product. As the number of adjustments increases, the separation power loss within the cascade will increase accordingly.

[0005] Therefore, an improved product abundance control method is needed to solve the aforementioned problems in the existing technology. Summary of the Invention

[0006] This invention proposes an automatic product abundance control method under a material flow and material handling control mode, which is used to solve the technical problem that the product abundance is adjusted frequently and by large magnitude during the material receiving process in the prior art, which easily leads to the product abundance being difficult to control stably.

[0007] The technical solution of the present invention:

[0008] An automatic product abundance control method under a material flow and feed control mode includes the following steps:

[0009] Step 1: Set the control signal;

[0010] Step 1.1 Select the control time point;

[0011] Step 1.2 Calculate the maximum abundance deviation;

[0012] Step 1.3: Set control signals in segments;

[0013] Step 2: Control signal feedback;

[0014] Step 3: Calculate the material handling pressure adjustment amount;

[0015] Step 3.1 Calculate the instantaneous abundance target value;

[0016] Step 3.2 Calculate the target control pressure for material handling;

[0017] Step 4: Adjust the pressure using the regulator.

[0018] Step 1.1, selecting the control time point, includes: based on actual product production data, calculating the average time T1 when the bottle abundance enters the control limit, and using this as the control signal boundary point.

[0019] Step 1.2, calculating the maximum abundance deviation, includes: collecting the instantaneous abundance when the external parameters are stable during a certain operating process, calculating the maximum deviation of the system's instantaneous abundance, and, based on the control accuracy of the control pressure P2 of the control equipment, calculating the maximum deviation μ of the bottled abundance according to the relationship between instantaneous abundance, control pressure, and bottled abundance. 瓶 .

[0020] Step 1.3, segmenting the control signals, includes:

[0021] μ0 is selected as the product control accuracy, which is the deviation between the bottled abundance and the target product abundance.

[0022] Using T1 as the time node, the upper limit C of the bottled abundance is set in segments. upper and lower limit C lower At this point, the coordinates of the upper limit control line of the receiving starting point are (0, C0+μ). 瓶 The lower limit control line coordinates are (0, C0-μ). 瓶 ); The upper limit control line coordinates (T1, C) at time T1 when entering the control range upper The lower limit control line coordinates (T1, C) at the moment of entering the control range lower ).

[0023] At this point, the following equation for calculating the abundance control signal of bottled products can be obtained: (1)

[0024]

[0025] Similarly, we can obtain the following lower limit equation (2).

[0026]

[0027] Where: C upper —Control the upper limit;

[0028] C lower —Control the lower limit value;

[0029] C0 – Target product abundance;

[0030] μ瓶 —Maximum deviation in bottled abundance;

[0031] μ0 — Daily control precision of bottled abundance;

[0032] T1 — The shortest time for bottled abundance to enter the control limit range;

[0033] —The rate at which bottled abundance enters the control line;

[0034] Step 2: Control signal feedback includes: acquiring the instantaneous abundance at the current moment, calculating the current bottled abundance and the upper and lower limits of the control signal, and comparing them. If the bottled abundance does not meet C... lower ≤C 瓶 ≤C upper It sends out control and adjustment signals.

[0035] Step 3.1, calculating the instantaneous abundance target value, includes:

[0036] The target control value for the instantaneous abundance of the product in the later stage is calculated based on the current bottling abundance, bottling load, target bottling load, and target abundance of the container.

[0037]

[0038] In formula (3):

[0039] C target —Target control value for instantaneous abundance in the later stage

[0040] m 瓶 —Current container load

[0041] C 瓶 —Bottled abundance in the current container

[0042] m0 — Target loading capacity of the product container

[0043] C0 – Product target abundance.

[0044] Step 3.2, calculating the target control pressure for material handling, includes:

[0045] Based on the linear relationship between product feed quantity and product abundance, the relative change relationship between product feed quantity and instantaneous product abundance is obtained by fitting, as shown in the following formula (4):

[0046] δG P =β0+β1δC P …………(4)

[0047] The product feed rate can be converted into the control pressure before the orifice plate, i.e. after the regulator, as shown in the following formula (5):

[0048] G P =kP2d 2 ……………… (5)

[0049] In the formula:

[0050] d—orifice diameter, in cm;

[0051] k—orifice coefficient;

[0052] P2 — Regulator control pressure, unit kPa;

[0053] G P —Product feed rate, in g / s;

[0054] By combining the orifice plate calculation formula, the functional relationship between the feed pressure P2 and the instantaneous abundance change is obtained; by substituting the target value of the instantaneous abundance in the later stage and the current average instantaneous abundance, the target pressure is calculated.

[0055] Step 4: Regulator control pressure adjustment, including:

[0056] The pressure control deviation ΔP is set. When the deviation between the online operating pressure and the target pressure exceeds the set value, the regulator pressure value is adjusted to the target value by slightly opening and slightly closing the regulator valve. When the online operating pressure is less than the target pressure, the regulator valve is slightly opened, and when the online operating pressure is greater than the target pressure, the regulator valve is slightly closed.

[0057] The beneficial effects of this invention are:

[0058] This invention is applicable to the intelligent control of product abundance under material flow control in the field of centrifugal separation. This invention is a product abundance adjustment method with high stability, which reduces the frequency and magnitude of pressure adjustment of abundance in the container receiving stage, especially in the early stage of receiving. The product receiving process is more stable, and the average standard deviation of the abundance in the container bottling is generally less than 0.00004. Detailed Implementation

[0059] The following describes in detail, with reference to embodiments, a method for automatic control of product abundance under a material flow control mode according to the present invention.

[0060] An automatic product abundance control method under a material flow and feed control mode includes the following steps:

[0061] Step 1: Set the control signal;

[0062] Step 1.1 Select the control time point, including: based on actual product production data, calculate the average time T1 when the bottle abundance enters the control limit, and use it as the control signal boundary point.

[0063] Step 1.2 Calculate the maximum abundance deviation, including: collecting the instantaneous abundance when the external parameters are stable during a certain operation, calculating the maximum deviation of the system's instantaneous abundance, and, based on the control accuracy of the control pressure P2 of the control equipment, calculating the maximum deviation μ of the bottled abundance according to the relationship between instantaneous abundance, control pressure, and bottled abundance. 瓶 .

[0064] Step 1.3 Segmented setting of control signals, including:

[0065] μ0 is selected as the product control accuracy, which is the deviation between the bottled abundance and the target product abundance.

[0066] Using T1 as the time node, the upper limit C of the bottled abundance is set in segments. upper and lower limit C lower At this point, the coordinates of the upper limit control line of the receiving starting point are (0, C0+μ). 瓶 The lower limit control line coordinates are (0, C0-μ). 瓶 ); The upper limit control line coordinates (T1, C) at time T1 when entering the control range upper The lower limit control line coordinates (T1, C) at the moment of entering the control range lower ).

[0067] At this point, the following equation for calculating the abundance control signal of bottled products can be obtained: (1)

[0068]

[0069] Similarly, we can obtain the following lower limit equation (2).

[0070]

[0071] In the formula:

[0072] C upper —Control the upper limit;

[0073] C lower —Control the lower limit value;

[0074] C0 – Target product abundance;

[0075] μ 瓶 —Maximum deviation in bottled abundance;

[0076] μ0 — Daily control precision of bottled abundance;

[0077] T1 — The shortest time for bottled abundance to enter the control limit range;

[0078] —The rate at which bottled abundance enters the control line;

[0079] Step 2, Control Signal Feedback; includes: acquiring the instantaneous abundance at the current moment, calculating the current bottled abundance and the upper and lower limits of the control signal, and comparing them. If the bottled abundance does not meet C... lower ≤C 瓶 ≤C upper It sends out control and adjustment signals.

[0080] Step 3: Calculate the material handling pressure adjustment amount;

[0081] Step 3.1 Calculate the instantaneous abundance target value, including:

[0082] The target control value for the instantaneous abundance of the product in the later stage is calculated based on the current bottling abundance, bottling load, target bottling load, and target abundance of the container.

[0083]

[0084] In formula (3):

[0085] C target —Target control value for instantaneous abundance in the later stage

[0086] m 瓶 —Current container load

[0087] C 瓶 —Bottled abundance in the current container

[0088] m0 — Target loading capacity of the product container

[0089] C0 – Product target abundance.

[0090] Step 3.2 Calculate the target control pressure for material handling, including:

[0091] Based on the linear relationship between product feed quantity and product abundance, the relative change relationship between product feed quantity and instantaneous product abundance is obtained by fitting, as shown in the following formula (4):

[0092] δG P =β0+β1δC P …………(4)

[0093] The product feed rate can be converted into the control pressure before the orifice plate, i.e. after the regulator, as shown in the following formula (5):

[0094] G P =kP2d 2 ………………(5)

[0095] In the formula:

[0096] d—orifice diameter, in cm;

[0097] k—orifice coefficient;

[0098] P2 — Regulator control pressure, unit kPa;

[0099] G P —Product feed rate, in g / s;

[0100] By combining the orifice plate calculation formula, the functional relationship between the feed pressure P2 and the instantaneous abundance change is obtained; by substituting the target value of the instantaneous abundance in the later stage and the current average instantaneous abundance, the target pressure is calculated.

[0101] Step 4: Regulator control pressure adjustment, including:

[0102] The pressure control deviation ΔP is set. When the deviation between the online operating pressure and the target pressure exceeds the set value, the regulator pressure value is adjusted to the target value by slightly opening and slightly closing the regulator valve. When the online operating pressure is less than the target pressure, the regulator valve is slightly opened, and when the online operating pressure is greater than the target pressure, the regulator valve is slightly closed.

[0103] Example

[0104] Example: Taking the abundance adjustment of a certain centrifugal cascade product as an example, the receiving container started receiving materials at 22:36 on March 14, 2022. The target product abundance of the bottle is 4.0%, and the target filling volume of the container is 6000kg.

[0105] Step 1: Set the control feedback signal

[0106] Step 1.1 Select the control time point

[0107] Based on actual operation statistics, considering the non-steady-state process of scheme transformation, it generally takes about 30 hours (10 measurement points including 1 measurement of the non-steady-state process at 2 hours and 1 measurement of the steady-state process at 4 hours) for the bottle abundance of the production line to enter the control range. Therefore, segmented control signals are established with T1 = 30 hours as the boundary.

[0108] Step 1.2 Calculate the maximum abundance deviation

[0109] During a specific production run of a 4.65% product, when external and auxiliary parameters fluctuated within a certain range, 218 instantaneous data points were collected under the same control pressure P2. Statistical analysis of the data distribution revealed a maximum instantaneous abundance deviation of approximately 0.011%. The regulating device currently used on the product feed pipeline of the production line is a regulator, with a pressure control accuracy of σ. P =0.01kPa.

[0110] When calculating the bottling abundance of a product, the product receiving process is typically divided into several receiving processes at equal time intervals, thus deriving the formula for calculating bottling abundance.

[0111]

[0112] In the formula:

[0113] P i —The regulator controls the pressure during the i-th time interval;

[0114] Δt — time interval, which is usually taken as 4 hours;

[0115] —Average instantaneous abundance over the time interval;

[0116] At this point, the absolute deviation of the bottled abundance can be obtained as:

[0117]

[0118] in:

[0119]

[0120]

[0121] The maximum deviation μ of bottled abundance was calculated. 瓶 =0.015%.

[0122] Step 1.3 Setting up equations in segments

[0123] Select product control accuracy μ0 = 0.002%, μ 瓶 =0.015%. At this time, the upper limit control line coordinates of the receiving starting point product are (0, 4.0% + 0.015%), and the lower limit control line coordinates are (0, 4.0% - 0.015%). When entering the control range at time T1, the upper limit control line coordinates are (30, Cupper), and the lower limit control line coordinates when entering the control range are (30, Clower).

[0124] At this point, the equation for the upper limit of the bottled abundance control line can be obtained.

[0125]

[0126] Lower bound equation

[0127]

[0128] Step 2: Control signal feedback

[0129] At 9:00 AM on March 16, 2022, the current bottled volume was 1077 kg, the control pressure was 4.94 kPa, and the calculated bottled abundance was 3.9942%. The container had been running for 34.4 hours, exceeding 30 hours. Calculate the control signal value C at this time. upper =4.002%, C lower=3.998%. Bottled abundance is less than C. lower If the control limit is exceeded, a control signal will be issued.

[0130] Step 3: Calculation of material handling pressure adjustment

[0131] Step 3.1 Calculation of instantaneous abundance control target value

[0132] The instantaneous abundance control target value can be calculated according to formula (1).

[0133]

[0134] Step 3.2 Calculate the target control pressure for material handling.

[0135] The relative change in product abundance is linearly related to the relative change in product feed quantity. By fitting the data, a univariate linear regression model of the relative changes in product abundance and feed quantity is obtained.

[0136] δG P = -2.00 × 10 -5 -1.224δC P

[0137] By using the orifice plate calculation formula, ignoring the minimum term, and converting the product feed rate into regulator control pressure, the functional relationship between the change in instantaneous product abundance and the control pressure can be obtained as follows:

[0138]

[0139] In the formula:

[0140] P2 target —Target value for product material handling control pressure;

[0141] P2—Current product material handling control pressure;

[0142] C target —Target value for controlling the instantaneous abundance of the product;

[0143] C 瞬 —Current average instantaneous abundance of the product;

[0144] Substituting the instantaneous abundance target value of 4.0013% and the current average instantaneous abundance of 3.9935%, the target pressure of 4.928 kPa was calculated.

[0145] Step 4: Regulator control pressure adjustment

[0146] The set deviation value △P is 0.007 kPa. At this time, the difference between the target control pressure and the online pressure is -0.012 kPa, which exceeds the set deviation value and is lower than the current online pressure. Moreover, the online operating pressure is greater than the target pressure. Therefore, the regulator valve is slightly closed to adjust the regulator control pressure to 4.93 kPa.

[0147] The embodiments of the present invention have been described in detail above. The present invention is not limited to the above examples. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present invention.

Claims

1. A method for automatic product abundance control under a material flow and feed control mode, characterized in that, Includes the following steps: Step 1: Set the control signal; Step 1.1 Select the control time point; Step 1.2 Calculate the maximum abundance deviation; Step 1.3: Set control signals in segments; Step 1.3, segmenting the control signals, includes: μ0 is selected as the product control accuracy, which is the deviation between the bottled abundance and the target product abundance. Using T1 as the time node, the upper limit C of the bottled abundance is set in segments. upper and lower limit C lower At this point, the coordinates of the upper limit control line of the receiving starting point are (0, C0+μ). 瓶 The lower limit control line coordinates are (0, C0-μ). 瓶 ); The upper limit control line coordinates (T1, C) at time T1 when entering the control range upper The lower limit control line coordinates (T1, C) at the moment of entering the control range lower ); At this point, the following equation for calculating the abundance control signal of bottled products can be obtained: (1) Similarly, we can obtain the following lower limit equation (2). Where: C upper —Control the upper limit; C lower —Control the lower limit value; C0 – Target product abundance; μ 瓶 —Maximum deviation in bottled abundance; μ0 — Daily control precision of bottled abundance; T1 — The shortest time for bottled abundance to enter the control limit range; —The rate at which bottled abundance enters the control line; Step 2: Control signal feedback; Step 3: Calculate the material handling pressure adjustment amount; Step 3.1 Calculate the instantaneous abundance target value; Step 3.2 Calculate the target control pressure for material handling; Step 4: Adjust the pressure using the regulator.

2. The method for automatic product abundance control under a material flow control mode according to claim 1, characterized in that: Step 1.1, selecting the control time point, includes: based on actual product production data, calculating the average time T1 when the bottle abundance enters the control limit, and using this as the control signal boundary point.

3. The method for automatic product abundance control under a material flow and material handling control mode according to claim 2, characterized in that: Step 1.2, calculating the maximum abundance deviation, includes: collecting the instantaneous abundance when the external parameters are stable during a certain operating process, calculating the maximum deviation of the system's instantaneous abundance, and, based on the control accuracy of the control pressure P2 of the control equipment, calculating the maximum deviation μ of the bottled abundance according to the relationship between instantaneous abundance, control pressure, and bottled abundance. 瓶 .

4. The method for automatic product abundance control under a material flow and material handling control mode according to claim 3, characterized in that: Step 2: Control signal feedback includes: acquiring the instantaneous abundance at the current moment, calculating the current bottled abundance and the upper and lower limits of the control signal, and comparing them. If the bottled abundance does not meet C... lower ≤C 瓶 ≤C upper It sends out control and adjustment signals.

5. The method for automatic product abundance control under a material flow and material handling control mode according to claim 4, characterized in that: Step 3.1, calculating the instantaneous abundance target value, includes: The target control value for the instantaneous abundance of the product in the later stage is calculated based on the current bottling abundance, bottling load, target bottling load, and target abundance of the container. In formula (3): C target —Target control value for instantaneous abundance in the later stage m 瓶 —Current container load C 瓶 —Bottled abundance in the current container m0 — Target loading capacity of the product container C0 – Product target abundance.

6. The method for automatic product abundance control under a material flow and material handling control mode according to claim 5, characterized in that: Step 3.2, calculating the target control pressure for material handling, includes: Based on the linear relationship between product feed quantity and product abundance, the relative change relationship between product feed quantity and instantaneous product abundance is obtained by fitting, as shown in the following formula (4): δG P =β0+β1δC P …………(4) The product feed rate can be converted into the control pressure before the orifice plate, i.e. after the regulator, as shown in the following formula (5): G P =kP2d 2 ……………… (5) In the formula: d—orifice diameter, in cm; k—orifice coefficient; P2 — Regulator control pressure, unit: kPa; G P —Product feed rate, in g / s; By combining the orifice plate calculation formula, the functional relationship between the feed pressure P2 and the instantaneous abundance change is obtained; by substituting the target value of the instantaneous abundance in the later stage and the current average instantaneous abundance, the target pressure is calculated.

7. The method for automatic product abundance control under a material flow and material handling control mode according to claim 6, characterized in that: Step 4: Regulator control pressure adjustment, including: The pressure control deviation ΔP is set. When the deviation between the online operating pressure and the target pressure exceeds the set value, the regulator pressure value is adjusted to the target value by slightly opening and slightly closing the regulator valve. When the online operating pressure is less than the target pressure, the regulator valve is slightly opened, and when the online operating pressure is greater than the target pressure, the regulator valve is slightly closed.

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