Background
Inland brackish groundwater is a vital freshwater resource, yet point-of-use (POU) reverse osmosis systems often struggle with low recovery rates and high specific energy consumption. Traditional small-scale systems typically discard a large percentage of feed water as waste brine to manage membrane fouling, which is unsustainable in resource-constrained environments.
The Problem
Existing high-recovery POU desalination options lack robust, adaptive control architectures required to manage fluctuating feed water salinity and varying operating conditions. Semi-batch RO systems are promising, but they introduce new complexities in managing time-variant osmotic pressure, which can accelerate membrane scaling and reduce system lifetime.
The Solution
We developed a closed-loop, sensor-driven control platform for a semi-batch RO prototype. By employing real-time monitoring of permeate conductivity, pressure, and flow rates, the system dynamically optimizes valve timings and pump speeds. This reduces membrane scaling risks while maximizing freshwater recovery. For more information, a presentation from the European Desalination Society 2024 conference is included here.
