The working principle of reverse osmosis water treatment equipment is mainly reverse osmosis technology. The solvent (usually water) in the solution is separated by a reverse osmosis membrane (a semi-permeable membrane) with sufficient pressure, and the direction is opposite to the osmosis direction. The reverse osmosis method with osmotic pressure greater than that can be used to separate, purify and concentrate the solution. Using reverse osmosis technology can effectively remove dissolved salts, colloids, bacteria, viruses, bacterial endotoxin and most organic impurities in water. The main separation object of reverse osmosis membrane is the ion range in solution, which can effectively remove the salt in water without chemical agents, and the desalination rate of the system is generally above 98%. Therefore, reverse osmosis is the most advanced, energy-saving and environment-friendly seawater desalination method, and it has also become the mainstream pre-desalination process.