Multi-electrode composition measuring device and method
First Claim
1. An apparatus for identifying the amount of one or more components in a liquid, comprising:
- a controller operative to supply current in a prescribed voltage range, the voltage range being determined based upon an expected location of half-wave potentials for selected components to be detected;
a secondary electrode in electrical communication with the controller and operative to supply current in the prescribed voltage range;
a working electrode receiving current from said secondary electrode;
a current sensing device operative to detect the current intensity of said working electrode; and
calculating means in electrical communication with the current sensing device and the controller, the calculating means being operative to determine the derivative of current intensity versus voltage relative to a reference potential and determine the concentrations of one or more components in the liquid by identifying peaks in the derivative of current in expected locations of the half-wave potentials for the components to be detected, the calculating means being configured to adjust the prescribed voltage range of the controller in response to process parameters and the location of the peaks identified in order to facilitate quicker identification of the components.
0 Assignments
0 Petitions
Accused Products
Abstract
The Applicant'"'"'s invention comprises an apparatus and method for determining the amount of one or more components in a pulping liquor. At a first electrode, a varying voltage is supplied in a voltage range including the half-wave potential of each component of a liquor to be measured, and accounting for variations in the half-wave potential caused by changing process parameters. At a second electrode, which is roughly ⅓ to ¼ the size of the first electrode, the derivative of current intensity is monitored near the known half-wave potential for the various liquor components. Using curve-fitting means, the derivative of current intensity and selected other process condition data is used to determine concentrations of the various liquor components.
333 Citations
16 Claims
-
1. An apparatus for identifying the amount of one or more components in a liquid, comprising:
-
a controller operative to supply current in a prescribed voltage range, the voltage range being determined based upon an expected location of half-wave potentials for selected components to be detected;
a secondary electrode in electrical communication with the controller and operative to supply current in the prescribed voltage range;
a working electrode receiving current from said secondary electrode;
a current sensing device operative to detect the current intensity of said working electrode; and
calculating means in electrical communication with the current sensing device and the controller, the calculating means being operative to determine the derivative of current intensity versus voltage relative to a reference potential and determine the concentrations of one or more components in the liquid by identifying peaks in the derivative of current in expected locations of the half-wave potentials for the components to be detected, the calculating means being configured to adjust the prescribed voltage range of the controller in response to process parameters and the location of the peaks identified in order to facilitate quicker identification of the components. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
-
-
10. A method of measuring the concentration of one or more components in a liquid, the method comprising the steps of:
-
producing a current flow at a voltage within a prescribed range at a first location in the liquid;
measuring the current flow in the liquid at a second location;
determining a derivative of the current flow versus voltage relative to a reference potential;
determining the concentration of the one or more liquid components by identifying peaks of the derivative of current flow versus voltage; and
adjusting the voltage within the prescribed range at the first location in response to process parameters and the peaks identified in order to facilitate quicker identification of the components. - View Dependent Claims (11, 12, 13, 14, 15, 16)
selecting a set of process conditions which effect the concentration of a component of the liquid to be measured;
creating a set of equations representing addition of current change and one or more of the selected set of process conditions, each process condition thereafter associated with an unknown weighting coefficient;
determining a lab value for each equation in the set;
performing linear regression to solve for the unknown weighting coefficient; and
creating one or more working equations using the solved-for weighting coefficients which are thereafter used to determine concentration of the one or more liquid components.
-
-
14. The method of claim 13 wherein the coefficient of correlation, R, is used to select which of the set of equations of selected process conditions is used to create the one or more working equations.
-
15. The method of claim 13 wherein the set of equations of selected process conditions represent all possible permutations of the selected set of current change and the one or more of the selected set of process conditions.
-
16. The method of claim 13 wherein the set of equations include at least current, derivative of current and the half-wave potential for the liquor component being measured.
Specification