Abstract: An improved containerized batch mixer is disclosed. The mixer container is loaded with particulate material and the lid assembly is locked in place. The container is then rolled onto the mixing station where left and right forks on the lower docking arm assembly slide into left and right container rails on the container assembly. The docking arm drive assembly is then activated to start the lower docking arms on their upward path. A screw jack turns to slowly raise the lower docking arms. Left and right fork guide pins engage left and right guide holes on the container support frame. The mixing container's spear point is axially aligned with an impeller drive socket by a guide stop collar. Finally, as the lower docking arms travel toward the upper docking arm, the spear point rotationally engages drive socket.