Silica Sand Washing: Attrition & Hydraulic Classification (2D)

This 2D companion swaps the 3D plant scene for a transparent side view built for reading the mineral processing rather than orbiting a rendered tank: grains fall from a feed chute into a rotating attrition scrubber where a clay-and-iron coating erodes off each one at a rate set by the washing-intensity slider — clay abrades quickly since it is a weak surface film, while iron-oxide staining is more tightly bonded and erodes slowly, which is why the product never quite reaches 100% SiO₂. Scrubbed grains then drop into a hydraulic classifier, where an adjustable upward water current fights each grain's own Stokes settling velocity: clean, heavy sand out-settles the current and sinks to the product underflow, while the fine clay and iron debris knocked loose upstream are too light to out-settle it and are swept to the waste overflow launder instead. Push the feed rate up and grains spend less real time in the scrubber before the current carries them on — more throughput for a little less cleaning, exactly the trade-off a real washing plant lives with. Every number in the readout panel — SiO₂ purity, Fe₂O₃ content, sand yield — is the live measured average of grains that actually finished the run.