Triple-effect brine evaporator (forward feed)

The classic multiple-effect evaporator, as a standalone drop-in template: a 6 wt% NaCl brine concentrated in three forward-feed effects down a pressure cascade (1.0 -> 0.70 -> 0.45 bar), where each effect's vapour boil-off is the heating steam for the next. Live 350 kPa steam drives only the first effect; the model reports the resulting steam economy, the per-effect boiling temperatures, and the concentrated liquor. Runs on the brine electrolyte package, so the boiling-point elevation is a real function of the salt as the liquor concentrates rather than an assumed offset.