Reverse osmosis technology is a well-developed desalination technology in the world, and it is also the most widely used and most applicable water treatment process in the market. It can precisely filter out bacteria, viruses, metal ions, salts, pesticides and various carcinogens in water. It has low working pressure, large water production, high salt rejection and easy maintenance. A large flow film will be automatically applied before and after each water production to extend its service life.