Digital control method and system thereof for solution replenishment system in the pad dyeing process with combination dyes

Abstract

A digital control method is to accurately calculate the real-time addition amount of each dye in the solution replenishment system in the whole dyeing process based on the initial dyeing rate of each dye, and replenish the dye solution according to the real-time addition amount. A digital control system includes an automatic calculation K.sub.0,n value unit, a central processing unit and a replenishment pump. The automatic calculation K.sub.0,n value unit is composed of a dye solution concentration detection instrument, a sensor I and a BP neural network model. The BP neural network model is a BP neural network trained by a dye database. The automatic calculation K.sub.0,n value unit transmits the K.sub.0,n value to the central processing unit, calculates the replenishment amount through the central processing unit, and controls the replenishment pump to replenish the solution.

Claims

1. A digital control method for a solution replenishment system in a pad dyeing process with combination dyes, comprising: accurately calculating a real-time addition amount of each dye in the solution replenishment system in a whole dyeing process based on an initial dyeing rate of each dye, and replenishing a dye solution according to the real-time addition amount; wherein during the color combination pad dyeing process, an initial dyeing time of fabric dipping in the dye solution is 4s-6s, a dyeing rate K.sub.0,n of each dye remains unchanged in the initial dyeing time, K.sub.0,n is an initial dyeing rate of an n-th dye in the dyeing process, n?1, and a number of dye types ?2, the time of the fabric dipping the dye solution in the pad dyeing tank is t, and an amount of the dye m.sub.t,n adsorbed to the fabric per unit gram at t is: $m_{t,n}=\frac{t}{60}?K_{0,n};$ in the formula, a unit of m.sub.t,n is mg.Math.g.sup.?1; a unit of t is s; a unit of K.sub.0,n is mg.Math.g.sup.?1.Math.min.sup.?1; wherein a calculation method of the initial dyeing rate K.sub.0,n of each dye comprises the following steps: through a Raman spectrometer, a spectrophotometer or a liquid chromatograph, detecting changes of a concentration of each dye in a formula dye solution along with a dyeing time under color combination dyeing conditions, calculating the amount of each dye on a fabric per unit mass according to the concentration of each dye at corresponding dyeing times in the dye solution, drawing a curve graph of the dyeing process, and obtaining a slope of a zero point from the fitted curve graph of the dyeing process as the initial dyeing rate K.sub.0,n; in the pad dyeing process, after dyeing for T time, the amount of the dye m.sub.T,n adsorbed to the fabric is:
m.sub.T,n=m.sub.t,n?T?X; in the formula, X is a weight of the dyed fabric per unit time; a unit of m.sub.T,n is g; a unit of T is min; a unit of X is g/min;
L.sub.r=L.sub.p; in the formula, L.sub.r is a volume of the replenishment solution with unit of mL; L.sub.p is a volume of the dye solution rolled onto the fabric through pad dyeing with unit of mL;
m.sub.r,n=m.sub.p,n+m.sub.T,n; in the formula, m.sub.T,n is a mass of the n-th component dye that needs to be added after dyeing for T time with unit of g; m.sub.p,n is a mass of the n-th component dye that rolled onto the fabric by a roller after dyeing for T time with unit of g; $m_{r,n}=\mathrm{TX}\left[C_n\left(P-\frac{K_{0,1}t}{6?{10}^4}-\frac{K_{0,2}t}{6?{10}^4}-.Math.-\frac{K_{0,n}t}{6?{10}^4}\right)/{?}_0+\frac{K_{0,n}t}{6?{10}^4}\right];$ wherein C.sub.n is an initial concentration of each dye in the dye solution with unit of g/mL; ?.sub.0 is a density of an initial pad dyeing solution with unit of g/mL; P is a solution carrying rate of the fabric with unit of %; wherein the accuracy refers to real-time addition grams of each dye in the combination dyes.

2. The digital control method of claim 1, wherein the initial dyeing rate of each dye is calculated on a same basis as the conditions of the pad dyeing process, wherein dye types, a concentration and proportion of dye solution, a dyeing temperature, a bath ratio, and an amount of additives are same.

3. The digital control method of claim 1, wherein the pad dyeing process with combination dyes comprises a pad dyeing process of acid dyes, reactive dyes, or direct dyes.

4. The digital control method of claim 1, wherein the pad dyeing process with combination dyes refers to a pad dyeing process with combination of more than two dyes.

5. The digital control method of claim 4, wherein the pad dyeing process with combination dyes is a process of continuously applying the dye solution to the fabric by a padder.

6. The digital control method of claim 1, wherein the initial concentration C.sub.n of the dye solution is 0.01 g/L-200 g/L; wherein a dyeing temperature is 10? C.-100? C., and wherein the dye solution further contains an amount of neutral salt, and the amount of neutral salt in the dye solution is 0 g/L-300 g/L.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a comparison graph of the change in the concentration of each dye in Example 1 between the original dye solution and the dye solution after calculating the concentration of the replenishment solution;

(2) FIG. 2 is a comparison graph of the color difference of the batch sample fabric in Example 1 between the original dye solution and the dye solution after calculating the concentration of the replenishment solution;

(3) wherein the original solution refers to the experimental result after replenishing at the concentration of the original dye solution, and the replenishment solution refers to the experimental result after replenishing at the concentration of the replenishment solution.

DETAILED DESCRIPTION OF THE EMBODIMENTS

(4) Based on above mentioned method, the following embodiments are carried out for further demonstration in the present invention. It is to be understood that these embodiments are only intended to illustrate the invention and are not intended to limit the scope of the invention. In addition, it should be understood that after reading the contents described in the present invention, those technical personnel in this field can make various changes or modifications to the invention, and these equivalent forms also fall within the scope of the claims attached to the application.

Example 1

(5) A digital control method for solution replenishment system in the pad dyeing process with combination dyes, is calculating the real-time addition amount K.sub.0,n of each dye in the solution replenishment system in the whole dyeing process based on the initial dyeing rate of each dye, that is the real-time addition gram of each dye, and replenishing the dye solution according to the real-time addition gram; the specific processes are as follows: (1) cut the cotton fabric into a number of cloth pieces with the same length and width of 3 g, prepare 5 g/L of mixed dye solution of Reactive Red 3BE and Reactive Blue M-2G mixed dye solution (with mass ratio of 1:1) and 60 g/L of sodium sulfate, place the cotton fabric in the mixed dye solution for color combination dyeing, control the bath ratio of 1:25, and the dyeing temperature of 40? C.; (2) calculate the initial dyeing rate K.sub.0,n of each dye: through a Raman spectrometer, a spectrophotometer or a liquid chromatograph, detecting changes of the concentration of each dye in a certain formula dye solution along with the dyeing time under certain color combination dyeing conditions, calculating the amount of each dye on a fabric per unit mass according to the concentration of each dye at different dyeing times in the dye solution, drawing a curve graph of the dyeing process, and obtaining a slope of the zero point from the fitted curve graph of the dyeing process as the initial dyeing rate K.sub.0,n specifically as follows:

(6) In order to obtain a more initial dyeing rate, in the early stage of dyeing, that is 2 min before dyeing, the data points taken are half of the data points in the whole dyeing process. Since the sampling interval of the first 2 min is too close to fast sample, and considering that the change of the dye solution after sampling is negligible, 6 groups of parallel dying experiments are set up with 6 points taken from each group, taking 800 ?L each time with a pipette gun and repeating the above experiments three times. Through the dyeing process curve of the three experiments tested by Raman spectroscopy, the average value is calculated at each time point, and the averaged dyeing rate curve is finally obtained as shown in FIG. 1, and nonlinear fitting is carried out on the dyeing process curve at the fixed point (0,0), so that the slope of the zero point is obtained as the initial dyeing rate K.sub.0,n. The calculation shows that: the initial dyeing rates of Reactive Red 3BE and Reactive Blue M-2G are respectively 28.10 mg.Math.g.sup.?1.Math.min.sup.?1 and 36.63 mg.Math.g.sup.?1.Math.min.sup.?1. (3) configure the same mixed dye solution of Reactive Red 3BE and Reactive Blue M-2G, and calculate the real-time addition amount in (g) of Reactive Red 3BE and Reactive Blue M-2G, the calculation formula is:

(7) $m_{r,n}=\mathrm{TX}\left[C_n\left(P-\frac{K_{0,1}t}{6?{10}^4}-\frac{K_{0,2}t}{6?{10}^4}-.Math.-\frac{K_{0,n}t}{6?{10}^4}\right)/{?}_0+\frac{K_{0,n}t}{6?{10}^4}\right];$ wherein C.sub.n is an initial concentration of the dye solution, K.sub.0,n is the initial dyeing rate of each dye with unit of mg.Math.g.sup.?1.Math.min.sup.?1, and n=2, which is the number of dye types; K.sub.0,1 is the initial dyeing rate of Reactive Red 3BE with unit of mg.Math.g.sup.?1.Math.min.sup.?1, and the value is 28.10 mg.Math.g.sup.?1.Math.min.sup.?1; K.sub.0,2 is the initial dyeing rate of Reactive Blue M-2G with unit of mg.Math.g.sup.?1.Math.min.sup.?1, and the value is 36.63 mg.Math.g.sup.?1.Math.min.sup.?1; ?.sub.0 is a density of an initial pad dyeing solution with unit of g/mL, and the value is 1.048 g/mL; P is a solution carrying rate of the fabric with unit of %, and the value is 74%; t is a time of fabric dipping in the pad dyeing solution with unit of s, and the value is 6 s; T is a time of pad dyeing with unit of min, and the value is 0.1 min; X is a weight of pad dyeing fabric per unit time with unit of g/min, and the value is 30 g/min.

(8) For color combination pad dyeing cloth pieces, after each piece was pad dyed, the dye solution is recovered, the volume of the dye solution to be added is 2.15 mL, the mass of Reactive Red 3BE and Reactive Blue M-2G to be added is 13.80 mg and 16.36 mg respectively, and the concentration of each dye to be added is 6.42 g/L and 7.61 g/L respectively.

(9) The concentrations of the dye solutions are tested after each group of the dye solution pad dyeing 5, 10, 15, 20 and 25 pieces of fabric respectively. Using the concentration of the original dye solution as the concentration of the replenishment solution and repeating the above experiment, after five groups of comparison, the changes in the concentration of each dye and in the corresponding color difference of the fabric between the original dye solution and the dye solution after calculating the concentration of the replenishment solution are respectively shown in FIG. 1 and FIG. 2.

Example 2

(10) A digital control system for solution replenishment system in the pad dyeing process with combination dyes, includes an automatic calculation K.sub.0,n value unit, a central processing unit and a replenishment pump; the automatic calculation K.sub.0,n value unit transmits the K.sub.0,n value from the sensor III to the central processing unit, calculates the replenishment amount through the central processing unit, and controls the replenishment pump to replenish the solution. The automatic calculation K.sub.0,n value unit is composed of a dye solution concentration detection instrument, a sensor I and a BP neural network model; wherein the dye solution concentration detection instrument is the Raman spectrometer, the spectrophotometer or the liquid chromatograph; the central processing unit is composed of a sensor II and a calculation processing unit.

(11) The digital control system for solution replenishment system in the pad dyeing process with combination dyes is used in the during the color combination pad dyeing process in Example 1, and the specific steps are as follows: (1) the value of each dye (the initial dyeing rate of each dye on the fabric per unit mass in the dyeing process) in multiple historical dye formulas is detected by Raman spectroscopy, and the historical dye formulas include two dyes (Reactive Red 3BE and Reactive Blue M-2G), taking one of the historical dye formulas as an example: first according to a historical dye formula, preparing 5 g/L of mixed dye solution of Reactive Red 3BE and Reactive Blue M-2G mixed dye solution (with mass ratio of 1:1) and 60 g/L of sodium sulfate, place the cotton fabric in the mixed dye solution for color combination dyeing, control the bath ratio of 1:25, and the dyeing temperature of 40? C.; calculating the amount of each dye on a fabric per unit mass according to the concentration of each dye at different dyeing times in the dye solution; drawing fitting curves of each dye amount-time on the fabric per unit mass calculated from the concentration of each dye at different dyeing times, the correlation coefficient of the dyeing amount-time fitting curve is not less than 0.90, and finally, performing first-order derivative processing of the dyeing amount-time fitting curve to obtain the slope of the dyeing amount-time fitting curve at the moment of 0, to obtain the K.sub.0,n value of each dye in the dye formula. Sequentially performing the above operations on multiple historical dye formulas to obtain the K.sub.0,n value of each dye in multiple historical dye formulas; (2) the amount of each dye on the fabric per unit mass calculated from the concentration of each dye at different dyeing times in multiple historical dye formulas and its corresponding K.sub.0,n value constitute the dye database, and the amount of each dye on the fabric per unit mass calculated from the concentration of each dye at different dyeing times in multiple historical dye formulas in the dye database and its corresponding K.sub.0,n value are used as input and output items respectively to train the neural network model, and the trained BP neural network model is obtained; the termination condition of the training is: the proportion of the number of the training samples identified by the error accounts for no more than 5% of the total number of the training samples, and the training samples identified by the error refers to the training samples whose K.sub.0,n values output by the BP neural network model are inconsistent with the actual values; (3) input the amount of each dye on the fabric per unit mass calculated from the concentration of each dye at different dyeing times in the dye formula of Reactive Red 3BE and Reactive Blue M-2G into the trained BP neural network model, which outputs the K.sub.0,n value of each dye; transmit the K.sub.0,n value of each dye from the sensor III to the central processing unit, and the real-time addition amount m.sub.r,n of each dye is calculated by the calculation formula in the digital control method of the solution replenishment system in the calculation processing unit, and finally, the addition amount of each dye is accurately controlled by the replenishment pump.