A filter cell cutaway with wash troughs, sand and anthracite media, a nozzle floor, air-scour blower and backwash pump cycles through service, drawdown, air scour, upward wash and rinse to waste. Watch the inlet, product and waste valves, and see retained solids, head loss and media expansion change. You can run the full sequence or select each stage manually.
• A real-time 3D view with numbered, clickable parts: filter cell and wash trough; sand / anthracite representation; nozzle floor and collection plenum; inlet, product and waste valves; air-scour blower and grid; backwash pump and waste return. Scene tools include home view, focus-selected-part, auto-rotate, expand and show/hide labels, and drag-to-orbit with pinch-to-zoom. • Experiment controls: influent suspended solids (20–200 mg/L); upward wash velocity (20–60 m/h); manual sequence stage (0–4); run complete sequence; product valve wrongly open during wash / rinse, plus a show flow/process markers toggle, pause/resume, single-step buttons (0.1 s and 1 s), a playback-speed selector and a restart trial action. • Live readouts: sequence index; retained solids; illustrative head loss; media expansion; product outlet flow; product outlet suspended solids. A model response curve is drawn beside the 3D view and updates as you change controls. • A Curves & measurements tab with two live charts, the model equations as written in the simulator and snapshot readouts; an Experiments tab with 2 guided presets (inspect upward wash; wrong product valve) plus a model-verification bench, timestamped event log and copyable trial report. • A Learn & assess tab with 3 lessons (dirty wash water goes to waste; air scour is not mass disposal; expanded media must settle before service), a 2-question knowledge check with reset, and a written model-scope statement.
During service, water flows down through the media, solids accumulate and illustrative head loss climbs. The demonstration schedule is compressed to service 20, drain 4, air 6, wash 10 and rinse 5 animation seconds, where one animation second represents one process minute. Air scour agitates the bed to loosen deposits, the upward wash lifts the media and carries solids toward the wash trough, and the rinse restores downflow and sends water to waste before return to service.
You can choose the upward wash velocity; the modeled expansion grows with velocity above 15 m/h up to 60%, and cleaning rate scales with velocity.
Dirty wash water belongs to the waste route. If you wrongly leave the product valve open during wash or rinse, contaminated water appears at the product outlet, which is the wrong-product-valve experiment. Air scour alone does not dispose of solids: in the model loosened material is retained until a liquid outlet removes it.
Cleaning and expansion are illustrative relations, not filter design curves. The equations assume a 3 m² filter at 60 m³/h with 95% capture, and the head-loss value is illustrative.
In the model they are service, drawdown, air scour, upward wash and rinse to waste. Each stage has its own valve positions and effect on the media and retained solids.
Air scour agitates the media and breaks solids loose from the grains. The upward wash then carries those loosened solids out with the wash water.
Dirty wash or rinse water reaches the product outlet instead of waste, so the product outlet flow and suspended solids show contamination.
After expansion the bed must restratify and be rinsed. The rinse stage restores downflow and sends the initial water to waste rather than to the product line.