Method and apparatus for agglomeration measuring and control

Abstract

The apparatus extracts samples of a fluid stream containing colloidal suspended solids at a detection station wherein the electrophoretic mobility (EM) of the colloidal suspended solids is determined. The detection station automatically measures the EM and provides such data to a computer, which computes the Zeta Potential. The computer also receives other information relating to the characteristics of the colloidal suspended solids, such as temperature, the percent of solids, and the flow rate of the fluid system. The computer is programmed to interpret the input data and to provide corrective signals to processing apparatus which automatically adjust and control the additives fed into the fluid stream to achieve automatic flocculation correction so that the agglomeration of the colloidal suspended solids in the fluid stream is optimized.

What is claimed is: 
     
       1. A method for determining the Zeta Potential of suspended colloidal particles comprising the steps of: a. establishing a predetermined voltage gradient along an electrophoresis cell positioned on a microscope stage,   b. introducing a sample of said suspended colloidal particles into said cell,   c. scanning a microscopic image of said colloidal particles within said cell,   d. tracking said particles to determine their movement,   e. storing data representative of said particle movement;   f. calculating the particle velocity from said data, and   g. determining the Zeta potential from said particle velocity, the voltage gradient of said cell, and the temperature of said suspended colloidal particles sample.   
     
     
       2. A method as in claim 1 wherein said particle velocity is determined from the total distance travelled by the individual particles and dividing said total distance by the number of particles observed during a fixed observation period. 
     
     
       3. The method as in claim 1 wherein said particle velocity is determined by differentiating a signal representative of said particle displacement with respect to time to provide a signal proportional to the rate of change of particle displacement. 
     
     
       4. A method as in claim 1 wherein the Zeta Potential is determined from the following formula: Zp= -k 1  (v e  /V) (1.45-0.02t c ) and wherein K 1  = 4πLn/D,   V e  is the electrophoretic velocity of said particles,   V is the voltage across said cell, t c  is the temperature of said sample, L is the length of said cell, D is the dielectric constant of said sample, and n is the viscosity of said sample.   
     
     
       5. A method as in claim 1 wherein the Zeta Potential is determined from the following formula: Zp=-k 2  (d/V) (1.45-0.02t c ) wherein K 2  = 4πLn/D, d is the distance travelled during a predetermined observation interval, V is the voltage of said cell, t c  is the temperature of said sample, L is the length of said cell, n is the viscosity of said sample and D is the dielectric constant of said sample and where K 2  includes said predetermined observation interval.   
     
     
       6. A method as in claim 1 wherein the Zeta Potential is determined from the following formula: Zp=(k 3  /tv) (1.45-0.02t c ) wherein -K 3  = 4πLn/D, T is the average time required for the particles to travel a predetermined distance, V is the voltage across said cell, and t c  is the temperature of said sample, L is the length of said cell, n is the viscosity of said sample and D is the dielectric constant of said sample and wherein K 3  includes said predetermined distance. .Iadd. 7. A method for determining the Zeta potential of suspended colloidal particles comprising the steps of:   a. establishing a pedetermined voltage gradient along an electrophoresis cell,   b. introducing a sample of said suspended colloidal particles into said cell,   c. tracking said particles to determine their movement during a fixed tracking period,   d. storing the data representative of said particle movement;   e. calculating the particle velocity from the movement of said particles by the total distance travelled by the individual particles and dividing said total distance by the number of particles observed during said fixed tracking period, and   f. determining the Zeta potential from said particle velocity, the voltage gradient of said cell, and the temperature of said suspended colloidal particles sample. .Iaddend..Iadd. 8. A method as in claim 7 further comprising the step of scanning said particles before said step of tracking. .Iaddend. .Iadd. 9. A method as in claim 7 wherein the Zeta Potential is determined from the following formula: ZP=-K 1  (V e  /V) (1.45 - 0.02t c ) and wherein K 1  =4π Ln/D, V e  is the electrophoretic velocity of said particles, V is the voltage across said cell, t c  is the temperature of said sample, L is the length of said cell, D is the dielectric constant of said sample, and n is the viscosity of said sample. .Iaddend..Iadd. 10. A method as in claim 7 wherein the Zeta Potential is determined from the following formula:   ZP=-K 2  (d/V) (1.45-0.02t c ) wherein K 2  =4πLn/D, d is the distance travelled during a predetermined observation interval, V is the voltage of said cell, t c  is the temperature of said sample, L is the length of said cell, n is the viscosity of said sample and D is the dielectric constant of said sample and where K 2  includes said predetermined observation interval. .Iaddend..Iadd. 11. A method as in claim 7 wherein the Zeta Potential is determined from the following formula:   ZP=(-K 3  /TV) (1.45-0.02t c ) wherein K 3  =4πLn/D, T is the average time required for the particles to travel a predetermined distance, V is the voltage across said cell, and t c  is the temperature of said sample, L is the length of said cell, n is the viscosity of said sample and D is the dielectric constant of said sample and wherein K 3  includes said predetermined distance. .Iaddend..Iadd. 12. Apparatus for determining the Zeta Potential of suspended colloidal particles from a sample of said suspended colloidal particles wherein the temperature thereof is known, comprising:     means for establishing a predetermined voltage gradient along an electrophoresis cell;   means for introducing said sample into said cell;   means for tracking said particles for determining their movement within said cell during a fixed tracking period;   means for storing data representative of the particle movement;   means for calculating the particle velocity from the movement of the particles determined by said means for tracking; and   means for determining the Zeta Potential from said particle velocity by determining the total distance travelled by the individual particles within said sample and by dividing said total distance by the number of particles tracked during said tracking period, the voltage gradient of said cell and the temperature of said suspended colloidal particles sample. .Iaddend. .Iadd. 13. Apparatus as in claim 12 wherein said means for determining the Zeta Potential includes means for differentiating a signal representative of the displacement of said particles with respect to time for providing a signal proportional to the rate of change of particle displacement to said means for determining. .Iaddend..Iadd. 14. Apparatus as in claim 12 wherein the Zeta Potential is determined from the following formula: ZP=-K 1  (V e  /V) (1.45-0.02t c ) and wherein K 1  =4πLn/D, V e  is the electrophoretic velocity of said particles, V is the voltage across said cell, t c  is the temperature of said sample, L is the length of said cell, D is the dielectric constant of said sample, and n is the viscosity of said sample. .Iaddend..Iadd. 15. Apparatus as in claim 12 wherein the Zeta Potential is determined from the following formula:   ZP=-K 2  (d/V) (1.45-0.02t c ) wherein K 2  =4π Ln/D, d is the distance travelled during a predetermined observation interval, V is the voltage of said cell, t c  is the temperature of said sample, L is the length of said cell, n is the viscosity of said sample and D is the dielectric constant of said sample and where K 2  includes said predetermined observation interval. .Iaddend. .Iadd. 16. Apparatus as in claim 12 wherein the Zeta Potential is determined from the following formula:   ZP=(-K 3  /TV) (1.45-0.02t c ) wherein K 3  =4πLn/D, T is the average time required for the particles to travel a predetermined distance, V is the voltage across said cell, and t c  is the temperature of said sample, L is the length of said cell, n is the viscosity of said sample and D is the dielectric constant of said sample and wherein K 3  includes said predetermined distance. .Iaddend. .Iadd. 17. A method for determining the Zeta potential of suspended colloidal particles comprising the steps of:     a. establishing a predetermined voltage gradient along an electrophoresis cell;   b. introducing a sample of said suspended colloidal particles into said cell;   c. tracking said particles to determine their movement;   d. calculating the particle velocity from the movement of said particles by differentiating a signal representative of said particle displacement with respect to time to provide a signal proportional to the rate of change of particle displacement; and   e. determining the Zeta potential from said particle velocity, the voltage gradient of said cell, and the temperature of said suspended colloidal particles sample. .Iaddend.