The aim of the present work is to study the rheological behavior of concentrated aqueous kaolin suspensions. Aqueous kaolin suspensions were prepared at various solids contents (40 to 55 wt％). Rheological tests were carried out at 25±0.1℃ 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 studied show a rheological behavior of the shearthinning type; in addition, the presence of a yield stress is noticed. Some rheological equations have been applied for describing the flow behavior of the kaolin mixes investigated: very satisfactory results were achieved using a new model proposed by the authors. Good correlations have been found between the rheological parameters and the solid volume fraction. The application of the Quemada model gave an insight into the particle aggregation phenomena at high shear.
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