The Difference Between Membrane Sheets: The manufacturing processes of conventional aromatic polyamide reverse osmosis composite membrane sheets are quite similar, involving the use of polyester nonwoven fabric as the base layer for structural strength. A layer of high permeability microporous polysulfone is pre-coated on the nonwoven fabric as a support layer, followed by interfacial bonding to form the ultra-thin separation functional layer, typically in a wet film form. For a dry film, the wet film sheet must be processed through a drying unit. Therefore, the difference between dry and wet film sheets lies in the fact that dry film sheets are made by drying the wet film sheets.
The Differences in the Coiling Process of Reverse Osmosis Membrane Elements: Wet membrane elements utilize wet membranes, while dry membrane elements use dry membranes. The coiling process for both has no significant differences.
The advantages of wet-type reverse osmosis membrane elements:
1All wet reverse osmosis membrane elements are tested for performance before they leave the factory, ensuring each element meets the standard and eliminating the possibility of defective products.
2The initial performance of the wet reverse osmosis membrane elements is superior. After simple flushing upon on-site installation, the membrane elements achieve their excellent performance, saving startup time and water resources for flushing.
3Wet membrane elements generally exhibit superior basic performance in reverse osmosis compared to dry membrane elements, meaning they have slightly better desalination rates and water production capabilities.
Disadvantages of wet-type reverse osmosis membrane elements:
1Wet membrane elements require a protective fluid or other protective measures to maintain a moist condition of the membrane elements and to prevent microbial contamination.
2Due to the membrane elements being in a wet state, they require transportation in insulated vehicles below the freezing point during winter or must be stored in a location above the freezing point upon arrival at the destination.
Advantages of Dry Reverse Osmosis Membrane Elements:
1The manufacturing technology and equipment for dry membrane elements are relatively complex, but dry membrane elements do not require protective fluids or other special protective measures. They are lightweight, with relatively lower transportation costs and can be stored for a longer period of time.
2The dry membrane elements, due to their non-wet nature, require no special vehicles for transport below the freezing point in winter, making transportation convenient and also placing lower demands on storage facility conditions.
Disadvantages of dry reverse osmosis membrane elements:
1Before shipment, membrane elements are randomly inspected; however, it cannot be guaranteed that the performance of each membrane element leaving the factory meets the standard, and there is a possibility that some elements may have defects.
2Membrane elements exhibit substandard initial performance after installation in the system, necessitating prolonged soaking and rinsing, which wastes time and water resources.
3The basic performance of membrane elements in reverse osmosis, such as water production and salt rejection rates, is generally slightly lower than that of wet membrane elements.
News Center Co., Ltd.
