On-line control and reaction process for pH adjustment

Patent metadata

Field	Value
Publication number	US-10316469-B2
Application number	US-201515537018-A
Country	US
Kind code	B2
Filing date	Dec 9, 2015
Priority date	Dec 16, 2014
Publication date	Jun 11, 2019
Grant date	Jun 11, 2019

Abstract

An on-line control and reaction process for pH adjustment and a control device for automatically adjusting pH value are provided. The process includes mixing a first enhancer and a second enhancer, optionally after diluting the first enhancer and/or the second enhancer with water, to form a mixture, setting a base pH value (δ1) and a target pH value (δ2), and adding pH adjuster into the mixture via a pH control unit and mixing to obtain a product with the target pH value. The pH control unit adjusts the adding of the pH adjuster by measuring or inputting certain parameters.

First claim

The invention claimed is:

1. An on-line control and reaction process for pH adjustment of a binary enhancer composition comprising a first enhancer and a second enhancer, the process comprising:
1) mixing the first enhancer and the second enhancer, optionally after diluting the first enhancer and/or the second enhancer with water, to form a mixture,
2) setting a base pH value (δ 1 ) and a target pH value (δ 2 ),
3) adding pH adjuster into the mixture via a pH control unit and mixing to obtain a product with the target pH value;

wherein the pH control unit adjusts the adding of the pH adjuster by measuring or inputting the following parameters:
a. the solid content ratio of the first enhancer in relation to the mixed product (r), said mixed product comprising the first enhancer and the second enhancer,
b. the solid content of the first enhancer (α) and the solid content of the second enhancer (β),
c. the pH value of the first enhancer (a) and the pH value of the second enhancer (b),
d. the base pH value (δ 1 ) and the target pH value (δ 2 ) as provided in step 2),
e. the flux of the product.

2. The process of claim 1 , wherein the pH control unit adjusts the flux of the pH adjuster via at least the related parameter, K 1 , K 2 , K 3 and K 4 and utilizing the following formula (1):
flux of pH adjuster= X ×( K 1 −K 2 +K 3 +K 4)  (1),

wherein
X represents the flux of the product (X);
K 1 represents the amount of pH adjuster consumed with pH value increasing from the initial pH value to the base pH value (δ 1 ) under varying solid content ratios of the first enhancer or second enhancer in relation to the mixed product (r), and satisfies K 1 =k 1 ×r+t, wherein k 1 is the slope obtained by linear fitting and t is the intercept;
K 2 represents the amount of pH adjuster consumed in relation to different pH values of the first enhancer (a) and different pH values of the second enhancer (b) under varying solid content ratios of the first enhancer or second enhancer in relation to the mixed product (r), and satisfies K 2 =2×r×k 2 Δ pH1 +2×(1−r)×k 2′ *Δ pH2 ,
wherein k 2 and k 2′ represents slope or average slope obtained by linear fitting in plotting the amounts of pH adjuster consumed with pH value increasing from the respective low limit pH value, high limit pH value and average pH value of two enhancers, in which said low limit pH value and high limit pH value are respectively the nominal lowest and highest pH value of the enhancer sample, and
Δ pH1 and Δ pH2 represent the difference between the inherent pH value of first enhancer, respectively second enhancer ((a) or (b)), and the average pH value of first enhancer, respectively second enhancer ((a ave. ) or (b ave. )), in which each of said average pH value ((a ave. ) or (b ave )) is an average determined from the pH values of n samples of the first or second enhancer and n is ≥50;
K 3 represents the effect of the difference between the target reaction index (δ 2 ) and base pH value (δ 1 ) on the amount of pH adjuster on the basis of K 2 , and satisfies K 3 =(2×r×k 2 +2×(1−r)×k 2 ′)×(δ 2 −δ 1 );
K 4 represents the effect of varying solid content (α) and solid content (β) on the amount of pH adjuster under base pH value (δ 1 ), and satisfies K 4 =k 4 ×(r×α/(1−r)×β)−C 1 ,
wherein k 4 represents slope obtained by linear fitting in plotting the amounts of pH adjuster consumed when the pH value is adjusted up to base pH value (β 1 ) against different solid content ratios of first enhancer to second enhancer,
C 1 is a value calculated from the formula r 0 *α theo. /((1−r 0 )*β theo. ) in case of the theoretical solid content of first enhancer(α theo. )and the theoretical solid content of second enhancer (α theo. ), in which r 0 is a standard ratio of first enhancer to the mixed product and is set to 1/2.

3. The process of claim 1 , wherein the first enhancer is a polyacrylamide enhancer and the second enhancer is a dialdehyde modified polyacrylamide enhancer.

4. The process of claim 1 , wherein the solid content of the first or second enhancer (αor β) is from 5 to 100%.

5. The process of claim 1 , wherein the pH value of the first or second enhancer (a or b) is from 2 to 8.

6. The process of claim 1 , wherein β 2 is 7.5 to 11.

7. The process of claim 1 , wherein the first enhancer is a polyacrylamide enhancer.

8. The process of claim 7 , wherein the polyacrylamide enhancer has a weight average molecular weight of from 500,000 to 5,000,000 g/mol.

9. The process of claim 3 , wherein the dialdehyde modified polyacrylamide enhancer has a weight average molecular weight of from 200,000 to 2,000,000 g/mol.

10. The process of claim 1 , wherein parameter K 5 is introduced to calibrate the actual concentration of pH adjuster,
K 5 =C nomimal /C 2 ,
in which C nomiunal is a nominal concentration of the product and C 2 is an actual concentration as measured of the product.

11. The process of claim 10 , wherein the flux of the pH adjuster=X×(K 1 −K 2 +K 3 +K 4 )×K 5 .

Assignees

• Ecolab Usa Inc

Inventors

• Zhang Meng
• Xu Na
• Li Jun
• Zhao Yulin

Classifications

• C08J2333/26

  Homopolymers or copolymers of acrylamide or methacrylamide · CPC title

• D21H17/375

  Poly(meth)acrylamide · CPC title

• D21H23/08

  by measuring pulp properties, e.g. zeta potential, pH · CPC title

• D21H23/10 Primary

  at least two kinds of compounds being added · CPC title

• D21H21/20

  Wet strength agents · CPC title