[EN]This paper reports the influence of calcining temperature on the rheology of blended cement pastes with 10 and 20% of thermally activated paper sludge as pozzolan at water/binder ratio of 0.5 and 0.4. The kaolinite based waste was activated at different activation temperatures (700–800 °C) and retention times of 2 and 5 h. The yield stress of the blended pastes increased when the activation intensity increased as a result of the increased calcite and free lime content. Due to the stiffness of the blended pastes, a superplasticiser (sodium lignosulfonate) was used in order to reduce the yield stress. The best results could be obtained using the lower calcining temperature (700 °C and 2 h).

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