The Thermoplastic Valve for Desalination segmentation by application distinguishes four primary process streams: Reverse Osmosis (RO), Electrodialysis (ED), Multi‑Stage Flash (MSF) and Multi‑Effect Distillation (MED). RO dominates the market, accounting for roughly 55 % of total valve demand, driven by its high recovery rates and widespread adoption in municipal and industrial water‑recycling projects. ED, representing about 20 %, serves niche brackish‑water and low‑salinity applications where energy consumption advantages outweigh lower throughput. MSF, with a 15 % share, is prevalent in large‑scale, high‑temperature plants, particularly in the Middle East, where waste‑heat integration justifies the higher capital cost. MED contributes the remaining 10 %, favored in regions with abundant low‑grade heat sources and stringent water‑quality specifications. Each application imposes distinct pressure, temperature, and chemical exposure profiles, directly influencing valve material selection, design complexity, and consequently the overall market size for thermoplastic solutions.