Membrane Storage

Handling and storage of new membrane elements

New polymeric membranes are conditioned with a preservative agent, typically an FDA compliant glycerol. This enables handling and distribution of the membranes in dry condition. Before the first use, this preservative is washed out and from this point on, the membrane must be kept wet for the remainder of its lifetime.

New membrane modules are supplied dry and sealed in a plastic bag to protect against oxidation. The membrane module should only be unpacked shortly before use. The product warranty includes up to 12 months of storage time when stored in the original packaging.

Recommended storage conditions: Temperature 5 – 25 °C. Do not expose to freezing temperatures. Do not store in direct sunlight.

Membranes in use

Once the preservative has been removed from the membrane, it should not be allowed to dry out. After each use, the membranes must be cleaned, and the system should be filled with liquid to prevent the membranes from drying out. For short term storage (1-2 days) clean water can be used. For longer term storage see “Recommended storage solutions” below.

Plan maintenance

If the filtration unit is disassembled, the membrane elements can be stored in closed containers. Make sure that the elements are submerged in liquid and that air is not entrapped within the elements. For short term storage (1-2 days) clean water can be used. For longer term storage see “Recommended storage solutions” below.

Recommended storage solutions

For longer term storage, the elements should be submerged in a suitable storage solution. In addition to keeping the membrane wet, this is mainly to prevent growth of microorganisms.
When selecting a storage solution, attention should be paid to the chemical limitations of the membrane.

Inspect the stored membranes regularly. Some solutions may oxidize during storage, others may exaporate over time, leaving the membrane dry and damaged. Check for microbial growth. If turbidity is seen, changes in pH is observed, or if the alcohol percentage has decreased below 20%, the storage solution should be exchanged.

The following storage solutions are recommended.

Carry out an appropriate cleaning cycle before the next production after storage

General information

If properly stored, membrane elements can be stored for many months or even years. Over time, functionality such as pore size, or durability will however be affected. The initial product warranty is not prolonged despite proper storage.

Membrane elements containing a preservative solution requires appropriate protective clothing, like gloves, safety glasses, etc. to ensure operator safety.

The information on this page is not intended to be exhaustive.

Please study the membrane specification sheets or contact the supplier for detailed information on chemical stability on storage conditions. The information on this page is meant as supplement to individual membrane specifications sheet, it is not intended to be exhaustive. Always read the individual specifications of your membrane before use. In no event will SANI Membranes be liable for any damages in relation to membranes or systems.