Although there are many industrial applications of liquid-solid flows in technology, the available knowledge of heat transfer to or from such flows is limited. In this study the effects of parameters on the enhancement of heat transfer from water-feldspar slurries flowing turbulently upwards in vertical annuli were investigated and the experimental conditions beneficial to the enhancement of heat transfer were determined. It was found that the heat transfer enhancement in upflow of slurries through a vertical annulus was a function of Prandtl and flow Reynolds numbers, the ratio of equivalent diameter to particle diameter, the aspect ratio of the inner pipe diameter to the outer pipe diameter and the concentration of solid particles in the slurry.