Abstract
Deep Cone Thickeners (DCTs) have been successful at consistently producing high underflow solids contents in many small to medium size applications. However, at high tonnages a lack of sufficient raking capacity with high yield stress muds has often resulted in disappointing performance. A patented spiral inner rake blade design utilizing a much longer blade replacing the standard inner rake blades is proving to be a key to getting improved performance at high tonnages. A full scale DCT installation with inner spiral blades running around 85,000 tpd is demonstrating world-beating performance on copper tailings, achieving 68 wt% underflow consistently. Two other retrofits with the spiral inner blade technology are currently in process and these will provide important comparative data.