Design Blueprint: Natural-Freeze Desalination Tray Array — Build Specification Derived from Freeze Desalination Priced Honestly (Natural Freezing Case)

DESIGN BLUEPRINT — SIMULATED, NOT MEASURED — NOT BUILT. Build specification for a seasonal natural-freeze desalination tray array, derived from the source paper https://doi.org/10.5281/zenodo.24109063 . Only the surviving natural-freezing design (Case A) is blueprinted; the refrigerated branch (Case B), rejected by the source paper's own accounting at 53.2 kWh/m3 at COP 2.5, is explicitly excluded. Design point: seawater at 35 g/L frozen in shallow trays by ambient winter air, ice layer grown to 50 mm before harvest, central case -10 C air in light wind (h = 10 W/m2/K) giving net product 13.25 L/m2/day, 7.55 m2 of tray per 100 L/day and 75.5 m2 per 1 m3/day, net yield 0.765 kg product per kg frozen after displacement washing at 0.235 kg of product per kg of ice, 100-day assumed window below -10 C, purchased-energy allowance 0.2 kWh/m3 for handling. The blueprint specifies a 1.0 m by 1.0 m tray module (45.85 kg ice and 35.07 L net product per batch), an 8-module household array for 100 L/day and a 76-module community array for 1 m3/day, with bill of materials, construction and commissioning sequence, operating envelope from the source paper's Table 2, critical fits, failure modes, and seasonal maintenance in ice-handling terms (1307.4 kg of gross ice per m3 of net product). Product storage against warm months was not sized in the source paper and is flagged; an optional store equal to one season of net product (10.6 m3 household, 100.7 m3 community) is a blueprint-stage derivation computed in the package's compute.py.