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pH control of a continuous precipitator
Author(s) -
Attarian C.,
Baker C. G. J.,
Svrcek W. Y.
Publication year - 1976
Publication title -
the canadian journal of chemical engineering
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.404
H-Index - 67
eISSN - 1939-019X
pISSN - 0008-4034
DOI - 10.1002/cjce.5450540543
Subject(s) - stoichiometry , decomposition , calcium carbonate , chemistry , materials science , mathematics , thermodynamics , analytical chemistry (journal) , chromatography , physics , composite material , organic chemistry
The size distribution of precipitates formed in a double decomposition reaction has been found previously to be highly sensitive to pH. Consequently, automatic control of pH is necessary to maintain a constant product size distribution. In the present study, steady‐state, dynamic, and pH control tests were performed on a continuous precipitator in which calcium carbonate was produced. Agreement between the experimental dynamic response and that predicted by a model based on equilibrium and stoichiometry was poor. However, satisfactory feedback control of the pH was achieved using proportional plus integral action. Simultaneous measurements of the precipitate size distribution using a Coulter Counter demonstrated that this resulted in good conrol of the mean paricle size.