Patent · US Expired

Method of measuring backelectromotive forces of aluminum electrolysis cells

US4488117A · kind A · utility

3Cited by
0References
7Claims
0Family size

Assignee

Inventor

Key dates

Filing dateApr 21, 1982
Grant dateDec 11, 1984
Priority date
Expiry dateApr 21, 2002

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC25C3/20
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A backelectromotive force of an aluminum electrolysis cell is measured by the steps of: (a) repeatedly measuring voltage V and current I of the cell at a short interval; (b) forming groups of data each including measured values thus obtained within a relative short period; (c) calculating a constant e and its variance Ve with reference to each data group according to a linear regression expressed by an equation: EQU V=r.multidot.I+e where r represents an internal resistance of the cell; (d) calculating a backelectromotive force E and its variance V.sub.E at a given time based on the constant e and its variance Ve calculated at the step (c), a backelectromotive force E' and its variance V'.sub.E with reference to a data group preceding the given time and a constant V.sub.T, and according to the following equations: EQU P=(V'.sub.E +V.sub.T)/(Ve+V'.sub.E +V.sub.T) EQU E=P.multidot.e+(1-P).multidot.E' EQU V.sub.E =P.sup.2 .multidot.Ve+(1-P).sup.2 .multidot.(V'.sub.E +V.sub.T); and (e) repeating the steps (b), (c) and (d) at a relatively short interval.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.