In closed-loop hydroponics, non-essential sodium ions ($Na^+$) accumulate in recirculating drain water, eventually elevating osmotic pressure and impairing water uptake. Integrating low-energy Reverse Osmosis (RO) membranes equipped with isobaric pressure exchangers (PX) achieves $>99.2\%$ sodium rejection at specific energy consumptions under $0.85\text{ kWh/m}^3$.
1. The Solution-Diffusion Permeation Model
J_w = A \times (\Delta P - \Delta \pi), \quad J_s = B \times (C_{feed} - C_{perm})
Recovering up to $80–85\%$ of drain water eliminates environmental runoff and saves up to $3,200\text{ m}^3$ of freshwater per hectare annually.
2. Interactive RO Desalination Optimizer
Calculate membrane flux, energy recovery, and water savings online: