dow filmtec bw4040

The numbers 4040 and 8040 refer to the dimensions of reverse osmosis (RO) membranes commonly used in water treatment systems:   4040 RO Membrane: The numbers "40" represent the nominal diameter of the membrane module in inches, and the "40" in "4040" specifically indicates a 4-inch diameter. Thus, a 4040 membrane has a nominal diameter of 4 inches. This membrane size is commonly used in small to medium-sized RO systems, such as those used in residential, commercial, or light industrial applications.   8040 RO Membrane: Similar to the 4040 membrane, the numbers "80" represent the nominal diameter of the membrane module in inches. Therefore, an 8040 membrane has a nominal diameter of 8 inches. This larger membrane size is typically used in larger-scale RO systems, such as those in industrial or municipal applications, where higher water production rates are required.   In summary, the key difference between a 4040 membrane and an 8040 membrane is the size or diameter of the membrane module. The larger 8040 membrane is capable of handling higher water flow rates and is commonly used in larger-scale RO systems, while the 4040 membrane is used in smaller to medium-sized systems.