🧂 Brine Graduation Tower: Evaporation, Salinity and Mass Balance (2D section)

Side section of a salt-works graduation tower: brine trickles down a brushwood wall, wind and dry air evaporate water, and the outlet salinity climbs until the salt saturates and a crust forms. Same mass-balance solver as the 3D page, with closure, steady-state, vapour-pressure and evaporation-law checks.