Arash Khosravi

Freshwater scarcity and industrial expansion in arid regions have increased the demand for seawater desalination. This process generates large volumes of brine. Traditionally, brine is considered a waste stream with significant environmental risks. However, it contains valuable resources such as water, energy, and minerals like lithium, magnesium, and calcium. Growing environmental regulations and the rising demand for battery-grade lithium have made resource recovery a priority. This approach aligns with Circular Economy and Zero Liquid Discharge (ZLD) strategies. In this study, several desalination scenarios were designed and investigated for the Persian Gulf region. Multi-Effect Distillation (MED) and Reverse Osmosis (RO) were selected as baseline systems. These were compared with hybrid configurations integrating RO with Membrane Distillation (MD), Brine Crystallization (BCr), chemical precipitation, and selective adsorption. Other components included solar evaporation ponds and Nanofiltration (NF). Operational data for energy, chemicals, and equipment were determined using process simulations and engineering calculations. The environmental performance was analyzed using Life Cycle Assessment (LCA). This analysis focused on climate change, human toxicity, ecotoxicity, ozone depletion, and fossil fuel depletion. The results showed that baseline scenarios (MED and RO) result in low water recovery and the loss of minerals in the effluent. In contrast, hybrid scenarios significantly improved both water and lithium recovery. It was observed that the RO MD BCr Pr configuration achieved the highest lithium recovery, exceeding 90 percent. Although selective adsorption and solar ponds showed high efficiency, Nanofiltration reduced final yields due to lithium passage through the membrane. Regarding energy consumption, scenarios with crystallizers had the highest demand. However, the use of solar thermal collectors reduced fossil fuel dependency and improved the environmen