Cooling System Rescue: Redesign the Failed Mining Pump Impeller

Context

Rio Seco Mining's underground copper operation in Chile runs 24/7 dewatering pumps to keep the 800m-deep extraction tunnels dry. Last month, their primary pump train failed catastrophically — the cast iron impeller on Pump Unit #3 suffered cavitation erosion so severe that efficiency dropped 40% in just six weeks, triggering an emergency shutdown.

The root cause is clear: the original impeller was specified for clean water, but the actual pumped fluid contains 2-5% suspended solite (ite fines, pH 3.2 acidic mine drainage, and temperatures spiking to 55°C during summer months. Rio Seco needs a replacement impeller design that survives this environment — and they need it specified in 72 hours before the wet season hits.

You've been brought in as the lead mechanical engineer to make the call.

Your Goal

Design a replacement impeller concept for the existing pump casing (Warman 8/6 E-AH equivalent, 750 RPM, 50m head, 400 m³/hr flow) that will survive at least 18 months in this abusive service — without requiring casing modifications or driver changes.