Cyclonic Separator

A cyclonic separator at Kandos Cement Works hangs from the steelwork of the preheater tower, an inverted cone of welded steel plate around two metres tall, narrowing to a discharge chute at its lower point. Riveted flanges run around the upper rim where the inlet ducting meets the body. The steel is darkened from decades of hot exhaust gas passing through, the joins streaked where dust has bled out at the seams. A counterweighted flap valve hangs from the discharge below, designed to seal the cone against pressure changes while letting the separated material drop through. The separator is bolted to a steel platform, accessed from a walkway that runs along one side. The light up here, near the top of the works, comes in through gaps in the upper cladding.

A cyclonic separator does what its name says. Dust-laden air enters the top of the cone tangentially, spins around the inner wall, and the heavier particles fall to the bottom while the cleaned air rises through a central pipe. In a cement works, cyclones are stacked vertically through the preheater tower to capture raw-meal dust from the hot exhaust gases coming up from the kiln. The captured meal is fed back into the kiln, and the cleaned gas continues to the stack. Kandos Cement Works ran this preheater system from at least its 2007 modernisation onward, and across the broader 95-year operational life of the plant in older forms. The works closed in September 2011.