Multi-electrode composition measuring device and method
AssigneeHoneywell-Measurex Corporation
InventorOrd Millar
Life of this patent
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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.
Claims16
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.
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.
Dependencies are inferred from the claim text.