Integrated rheological detection and automatic control method and device

Abstract

The invention discloses an integrated rheology detection and automatic control method and device. The method comprises the following steps: S1, acquiring a viscosity detection value of slurry; s2, the viscosity detection value of the slurry is compared with a viscosity set value, if the viscosity difference value exceeds a set range, the viscosity is dynamically adjusted through a pre-established logic control model, and the logic control model is used for adjusting the viscosity difference value within the set range by adjusting model factors related to the viscosity; the model factors include a temperature factor and a pressure factor associated with viscosity. The temperature, the pressure and the rotating speed are dynamically adjusted through the logic control model, so that the viscosity is adjusted; through multi-parameter cooperative control, the rheological fluctuation amplitude of the slurry can be greatly reduced, the consistency of the slurry is improved, and the spinning spinnability and the strength uniformity of tows are improved.

Description

Technical Field

[0001] This invention relates to the field of para-aramid spinning production technology, specifically to an integrated rheological detection and automated control method and apparatus. Background Technology

[0002] In para-aramid spinning production, the rheological properties of the sizing agent (such as viscosity, elastic modulus, and shear stress) directly affect the spinneret's spinneret uniformity and fiber forming quality. Traditional offline viscosity testing methods (such as laboratory sampling analysis) have the following significant drawbacks: 1. Testing delay: Offline testing requires interrupting the production process, taking several hours, and cannot reflect the dynamic rheological state of the sizing agent in the pipeline in real time; 2. Delayed process adjustment: The delayed testing results lead to untimely adjustments to process parameters (such as temperature and stirring speed), easily causing fluctuations in the sizing agent's rheological parameters, affecting spinnability and fiber strength.

[0003] While existing technologies have improved the preparation system for para-aramid spinning solutions, they lack online monitoring and closed-loop control schemes for slurry rheology, resulting in insufficient production stability. Therefore, a device capable of online detection and closed-loop control of slurry rheology is needed. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art, realize online detection and closed-loop control of slurry rheology, and provide an integrated rheological detection and automated control method and device.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: An integrated rheological detection and automated control method includes the following steps: S1: Obtain the viscosity value of the slurry; S2: Compare the viscosity detection value of the slurry with the viscosity set value. If the viscosity difference exceeds the set range, the viscosity is dynamically adjusted using a pre-established logic control model. The logic control model is used to adjust the viscosity difference within the set range by adjusting the model factor related to viscosity. The model factors include a viscosity-related temperature factor; The relational expressions of the logic control model include: ; Where η is viscosity, A is temperature coefficient (A∈[-1,0]), T is temperature factor (T∈[70, 90]℃), η0 is viscosity at reference temperature T0, and E a R is the activation energy for viscous flow, and R is the gas constant.

[0006] Preferably, the viscosity setting value of the slurry is set in the range of [160, 220] Pa·s, and the viscosity difference setting value is set in the range of [-20, 20].

[0007] Preferably, the method for adjusting the viscosity-related model factors in the logic control model is as follows: using PID control to adjust the temperature factor based on the deviation between the set viscosity threshold and the detected viscosity data, so as to adjust the viscosity difference within the set range.

[0008] Preferably, the model factors further include a viscosity-related pressure factor, and the relational expression of the logic control model further includes: ; Where K is the pressure coefficient, P is the pressure factor, and β is the pressure viscosity coefficient; PID control is used to adjust the temperature factor and pressure factor based on the deviation between the viscosity set threshold and the detected viscosity data, so as to bring the viscosity difference within the set range.

[0009] Preferably, the pressure coefficient K ∈ [1×10] −8 1×10 −6 ], pressure factor P∈[0,10]MPa.

[0010] Preferably, the relational expression of the logic control model further includes: Where B is the speed coefficient, B∈(0,1], and W is the speed factor, W∈[20,40]rpm; PID control is used to adjust the temperature factor, pressure factor, and speed factor based on the deviation between the viscosity set threshold and the detected viscosity data, so as to bring the viscosity difference within the set range.

[0011] An integrated rheological detection and automated control device, used to implement the integrated rheological detection and automated control method, includes: The rheological parameter acquisition module is used to obtain the viscosity measurement value of the slurry; The control module is used to compare the viscosity detection value of the slurry with the viscosity set value. If the viscosity difference exceeds the set range, a pre-established logic control model is used for dynamic analysis and an adjustment signal is output. The logic control model is used to adjust the viscosity difference within the set range by adjusting the model factor related to viscosity. The execution module is used to adjust the model factors according to the adjustment signal output by the control module.

[0012] Preferably, the rheological parameter acquisition module uses a rheometer to detect viscosity and also includes a temperature detector to detect the temperature of the slurry. Both the rheometer and the temperature detector are installed on the conveying pipeline.

[0013] Preferably, the execution module includes a temperature adjustment unit for adjusting the temperature factor, the temperature adjustment unit being connected to the pipeline heating jacket for adjusting the temperature of the pipeline heating jacket.

[0014] Preferably, the system further includes a pressure detector located at the screw outlet. The execution module also includes a pressure regulating unit and a speed regulating unit, used to regulate the pressure factor and speed factor, respectively. The pressure regulating unit includes a frequency converter and a screw, used to regulate the screw extrusion pressure by adjusting the speed of the frequency converter. The speed regulating unit is located on the degassing tank and used to regulate the stirring rate of the degassing tank.

[0015] The beneficial effects of this invention are as follows: This invention uses a logic control model to adjust the temperature of the slurry, thereby adjusting the viscosity online. It also selects an appropriate temperature coefficient based on a set range, effectively adjusting the viscosity and improving the efficiency of dynamic viscosity adjustment. Furthermore, the logic control model can combine pressure and rotation speed for dynamic viscosity adjustment. Through multi-parameter coordinated control, it can significantly reduce the rheological fluctuations of the slurry, improving spinnability and the uniformity of filament strength. By precisely setting the temperature coefficient, pressure coefficient, and rotation speed, the temperature and pressure factors can be rapidly adjusted, significantly improving the efficiency of viscosity adjustment. Attached Figure Description

[0016] The present invention will now be described in further detail with reference to the accompanying drawings: Figure 1 This is a method block diagram of the present invention; Figure 2 This is a schematic diagram of the installation of the device of the present invention; Detailed Implementation

[0017] like Figure 1 As shown, the present invention provides an integrated rheological detection and automated control method, comprising the following steps: S1: Obtain the viscosity value of the slurry; S2: Compare the viscosity detection value of the slurry with the viscosity set value. If the viscosity difference exceeds the set range, the viscosity is dynamically adjusted using a pre-established logic control model. The logic control model is used to adjust the viscosity difference within the set range by adjusting the model factors related to viscosity. Model factors include a viscosity-related temperature factor, and the relational expressions for the logic control model include: ; Where η is viscosity, A is temperature coefficient (A∈[-1,0]), T is temperature factor (T∈[70, 90]℃), η0 is viscosity at reference temperature T0, and E aLet E be the viscous flow activation energy, and R be the gas constant. The viscous flow activation energy of aramid slurry is E. a Typically >50 kJ / mol, with the gas constant R taken as 8.314 J / mol·K.

[0018] The method for adjusting viscosity-related model factors using the logic control model is as follows: PID control is used to adjust the temperature factor based on the deviation between the viscosity setpoint and the detected viscosity data, thereby bringing the viscosity difference within the set range. Specifically, a single-loop PID control mode is employed.

[0019] Model factors may also include viscosity-related pressure factors, and the relational expressions of the logic control model also include: ; Where K is the pressure coefficient, P is the pressure factor, and β is the pressure viscosity coefficient. The pressure viscosity coefficient β of aramid slurries is typically around 10. -8 Pa - ¹~10 -9 Pa - Within the range of ¹.

[0020] PID control is used to adjust the temperature factor and pressure factor based on the deviation between the viscosity set threshold and the detected viscosity data, so as to bring the viscosity difference within the set range.

[0021] Based on the extended Arrhenius-Barus equation, expressions for the temperature coefficient A and pressure coefficient K are obtained. By precisely setting the range of the temperature coefficient A, accurate adjustment and control of the temperature factor T and pressure factor P can be achieved, thereby improving the adjustment efficiency.

[0022] The viscosity setting range for the slurry is [160, 220] Pa·s, and the viscosity difference setting range is [-20, 20]. The pressure coefficient K ∈ [1×10⁻⁶]. −8 1×10 −6 ], pressure factor P∈[0,10]MPa.

[0023] The relational expressions for the logic control model also include: ; Where B is the speed coefficient, B∈(0,1], and W is the speed factor, W∈[20,40]rpm.

[0024] Specifically, PID control is used to adjust the temperature factor, pressure factor, and speed factor based on the deviation between the set viscosity threshold and the detected viscosity data, so as to adjust the viscosity difference within the set range.

[0025] The method of this invention dynamically adjusts temperature, pressure, and rotation speed through a logic control model, thereby achieving viscosity adjustment; through multi-parameter coordinated control, it can greatly reduce the rheological fluctuation amplitude of the slurry, improve the spinnability and fiber strength uniformity; by precisely setting the temperature coefficient and pressure coefficient, the temperature factor and pressure factor can be quickly adjusted, significantly improving the efficiency of viscosity adjustment.

[0026] The present invention also provides an integrated rheological detection and automated control device for implementing the above-mentioned integrated rheological detection and automated control method, comprising: The rheological parameter acquisition module is used to obtain the viscosity measurement value of the slurry; The control module is used to compare the viscosity detection value of the slurry with the viscosity set value. If the viscosity difference exceeds the set range, the pre-established logic control model is used for dynamic analysis and output adjustment signal. The logic control model is used to adjust the viscosity difference within the set range by adjusting the model factor related to viscosity. The execution module is used to adjust the model factors according to the adjustment signal output by the control module.

[0027] The rheological parameter acquisition module includes a rheometer for measuring viscosity and a temperature sensor for measuring slurry temperature. The rheometer is embedded in the slurry delivery pipeline; specifically, it employs a vibration measurement principle to collect the slurry viscosity at different shear rates. The temperature sensor is also located in the slurry delivery pipeline. A pressure sensor is also included, located at the screw outlet. By sequentially acquiring and detecting data at the screw outlet, inside the degassing tank, and on the delivery pipeline of the para-aramid production line, dynamic monitoring of the slurry viscosity throughout the entire process is achieved.

[0028] The control module uses a host computer, which is connected to the rheometer.

[0029] The execution module includes a temperature regulation unit and a pressure regulation unit, used to regulate the temperature factor and pressure factor, respectively. The temperature regulation unit is connected to the pipeline heating jacket and is used to control the heating of the pipeline heating jacket. The pressure regulation unit includes a frequency converter and a screw, used to regulate the screw extrusion pressure by adjusting the speed of the frequency converter. The temperature regulation unit can directly control the opening or closing of the pipeline heating jacket, thereby increasing or decreasing the temperature of the conveying pipeline, and can also control the heating power of the pipeline heating jacket, thereby increasing or decreasing the heating efficiency and regulating the temperature of the conveying pipeline.

[0030] The execution module also includes a speed adjustment unit for adjusting the speed factor. The speed adjustment unit is located on the degassing tank and is used to adjust the stirring rate of the degassing tank.

[0031] In this embodiment, a rheometer is installed on the slurry conveying pipeline, with a sampling frequency of 10-50 Hz. The host computer sets the viscosity setpoint η1 to 200 Pa·s. When the viscosity η of a certain section of the conveying pipeline is detected to be 170 Pa·s, it is determined to be outside the set range. The host computer controls the temperature regulation unit to adjust the pipeline heating jacket to raise the temperature according to the logic control model. After the temperature rises for a certain period of time or the viscosity rises by a certain amount, if necessary, the pressure regulation unit and speed regulation unit can be combined to control and adjust the screw extrusion pressure and the degassing tank stirring speed, respectively, so that the viscosity can be restored to the set range in a short time. The following is a detailed description with reference to the embodiment.

[0032] In this embodiment, when using a logic control model for dynamic adjustment, only the temperature T is adjusted. The specific process is as follows: when When the temperature T is increased, the temperature T is increased by ΔT within each time period X, where X∈[1,3]min and ΔT∈[0.5, 2]℃; when When the temperature T is lowered, the temperature T is lowered by ΔT within each time period X, where X∈[1,3]min and ΔT∈[0.5, 2]℃; when At that time, the system stops adjusting the temperature.

[0033] In another embodiment, when using a logic control model for dynamic adjustment, only the temperature T and pressure P are adjusted. The specific process is as follows: when When the temperature T is increased, the temperature T is increased by ΔT within each time period X, where X∈[1,3]min and ΔT∈[0.5, 2]℃; After adjusting the temperature T for one time period X, the pressure P is reduced. Within each time period X, the pressure P is reduced by ΔP, where ΔP ∈ [0.1, 0.3] MPa. when When the temperature T is lowered, the temperature T is lowered by ΔT within each time period X, where X∈[1,3]min and ΔT∈[0.5, 2]℃; After adjusting the temperature T for one time period X, the pressure P is increased. Within each time period X, the pressure P is increased by ΔP, where ΔP ∈ [0.1, 0.3] MPa. when At that point, the system stops adjusting, and both temperature and pressure control cease.

[0034] In another embodiment, when dynamically adjusting using a logic control model, the temperature T, pressure P, and rotational speed R are adjusted, specifically as follows: when When the temperature T is increased, the temperature T is increased by ΔT within each time period X, where X∈[1,3]min and ΔT∈[0.5, 2]℃; After adjusting the temperature T for one time period X, the pressure P is reduced and the rotational speed R is increased. Within each time period X, the pressure P is reduced by ΔP and the rotational speed R is increased by ΔR, where ΔP ∈ [0.1, 0.3] MPa and ΔR ∈ [1, 5] rpm. when When the temperature T is lowered, the temperature T is lowered by ΔT within each time period X, where X∈[1,3]min and ΔT∈[0.5, 2]℃; After adjusting the temperature T for one time period X, the pressure P is increased and the rotational speed R is decreased. Within each time period X, the pressure P is increased by ΔP and the rotational speed R is decreased by ΔR, where ΔP ∈ [0.1, 0.3] MPa and ΔR ∈ [1, 5] rpm.

[0035] when At this point, the system stops adjusting, and temperature, pressure, and speed are all stopped being controlled.

[0036] This invention realizes the detection and automated control of slurry rheological consistency in para-aramid production lines. By detecting and dynamically adjusting the slurry viscosity online, the efficiency of process adjustment is significantly improved. Through multi-parameter collaborative control, the adjustment time of slurry rheological viscosity is effectively shortened, the efficiency of slurry rheological adjustment is improved, and the spinnability and fiber strength uniformity are enhanced. At the same time, the device can also be adapted to multiple processes in para-aramid production lines, making it highly practical.

[0037] The above are merely preferred embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope defined in the claims.

Claims

1. An integrated rheological detection and automated control method, characterized in that, Includes the following steps: S1: Obtain the viscosity value of the slurry; S2: Compare the viscosity detection value of the slurry with the viscosity set value. If the viscosity difference exceeds the set range, the viscosity is dynamically adjusted using a pre-established logic control model. The logic control model is used to adjust the viscosity difference within the set range by adjusting the model factor related to viscosity. The model factors include a viscosity-related temperature factor; The relational expressions of the logic control model include: ； Where η is viscosity, A is temperature coefficient (A∈[-1,0]), T is temperature factor (T∈[70, 90]℃), η0 is viscosity at reference temperature T0, and E a R is the activation energy for viscous flow, and R is the gas constant.

2. The integrated rheological detection and automated control method according to claim 1, characterized in that, The viscosity setting value of the slurry is set in the range of [160, 220] Pa·s, and the viscosity difference setting value is set in the range of [-20, 20].

3. The integrated rheological detection and automated control method according to claim 1, characterized in that, The method for adjusting the viscosity-related model factors in the logic control model is as follows: using PID control to adjust the temperature factor based on the deviation between the set viscosity threshold and the detected viscosity data, so as to adjust the viscosity difference within the set range.

4. The integrated rheological detection and automated control method according to claim 1, characterized in that, The model factors also include a viscosity-related pressure factor, and the relational expression of the logic control model also includes: ； Where K is the pressure coefficient, P is the pressure factor, and β is the pressure viscosity coefficient; PID control is used to adjust the temperature factor and pressure factor based on the deviation between the viscosity set threshold and the detected viscosity data, so as to bring the viscosity difference within the set range.

5. The integrated rheological detection and automated control method according to claim 4, characterized in that, Pressure coefficient K∈[1×10 −8 1×10 −6 ], pressure factor P∈[0,10]MPa.

6. The integrated rheological detection and automated control method according to claim 4, characterized in that, The relational expression of the logic control model also includes: ； Where B is the speed coefficient, B∈(0,1], and W is the speed factor, W∈[20,40]rpm; PID control is used to adjust the temperature factor, pressure factor, and speed factor based on the deviation between the viscosity set threshold and the detected viscosity data, so as to bring the viscosity difference within the set range.

7. An integrated rheological detection and automated control device, used to implement the integrated rheological detection and automated control method according to any one of claims 1-6, characterized in that, include: The rheological parameter acquisition module is used to obtain the viscosity measurement value of the slurry; The control module is used to compare the viscosity detection value of the slurry with the viscosity set value. If the viscosity difference exceeds the set range, a pre-established logic control model is used for dynamic analysis and an adjustment signal is output. The logic control model is used to adjust the viscosity difference within the set range by adjusting the model factor related to viscosity. The execution module is used to adjust the model factors according to the adjustment signal output by the control module.

8. The integrated rheological detection and automated control device according to claim 7, characterized in that, The rheological parameter acquisition module uses a rheometer to detect viscosity and also includes a temperature detector to detect the temperature of the slurry. Both the rheometer and the temperature detector are installed on the conveying pipeline.

9. The integrated rheological detection and automated control device according to claim 7, characterized in that, The execution module includes a temperature regulation unit for adjusting the temperature factor. The temperature regulation unit is connected to the pipeline heating jacket for adjusting the temperature of the pipeline heating jacket.

10. The integrated rheological detection and automated control device according to claim 9, characterized in that, It also includes a pressure detector, which is installed at the screw outlet. The execution module also includes a pressure regulating unit and a speed regulating unit, which are used to regulate the pressure factor and speed factor, respectively. The pressure regulating unit includes a frequency converter and a screw, which is used to regulate the screw extrusion pressure by adjusting the speed of the frequency converter. The speed regulating unit is installed on the degassing tank and is used to regulate the stirring rate of the degassing tank.

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