Rheological properties of calcium carbonate concentrated suspensions: effects of solid content and dispersant concentration

• Autorzy: Papo A. , Piani L.
• Konferencja: Proceedings of the International Conference on Engineering Rheology ICER '99
• Języki publikacji: EN

Abstrakty

EN

The aim of the present work is to study the flow behaviour of calcium carbonate suspensions in order to determine the effectiveness of some commercial dispersing agents. Three commercial deflocculants were used: a sodium polyphosphate, a sodium salt of benzenedisulfonic acid, and a sodium polyacrylate. Calcium carbonate aqueous suspensions were prepared at various solid volume fractions (0.31 to 0.46). Rheological tests were carried out at 25oC by using the rate controlled coaxial cylinder viscometer Rotovisko-Haake 20, system M5-osc., measuring device MV1P with serrated surfaces. The tests were performed under both continuous and oscillatory flow conditions. All the suspensions prepared without deflocculant show a rheological behaviour of the shearthinning type; good correlations between relative viscosity and shear rate data were found by applying the Quemada model. The application of both static and oscillatory techniques permitted to evaluate the efficiency of dispersing agents. The sodium polyacrylate proved to be the most effective deflocculant for calcium carbonate slurries; the highest efficiency of sodium polyacrylate can be explained on the basis of its polymeric nature.

Słowa kluczowe

EN

suspensions; calcium carbonate; deflocculants

PL

reologia

• Wydawca: Oficyna Wydawnicza Uniwersytetu Zielonogórskiego
• Czasopismo: Applied Mechanics and Engineering
• Rocznik: 1999
• Tom: Vol. 4, no spec.
• Strony: 393--397
• Opis fizyczny: Bibliogr. 6 poz., wykr.

Twórcy

autor

Papo A.

autor

Piani L.

• Dipartimento di Scienze e Tecnologie Chimiche. Universita degli Studi di Udine. Via Cotonificio, 108. I-33100 Udine. Fax: [phone]. ITALY