Membrane-distillation wetting control

A distillation membrane lets water vapour pass while holding salty liquid back. Fouling can slow it down. Can the membrane keep producing separated water through repeated fouling and cleaning, without its pores starting to admit the salty liquid?[1] [2]

Membrane distillation separates water by maintaining vapour-filled pores between a warm salty feed and the receiving side. The hydrophobic pore walls resist liquid entry; if the pores wet, that separation can fail. The engineering question is how to control biofilms and deposits over prolonged operation while preserving salt rejection through repeated cleaning and thermal stress.

Seawater cleaning studies have recovered performance without wetting under their tested conditions. A 2026 study found benefits at 45 and 55°C but wetting under combined thermal and oxidative stress at 65°C. Those temperatures describe that experiment, rather than a universal safe range or failure threshold.[1] [2]

Cleaning away deposits can restore the amount of water passing through, yet damage the barrier that keeps salt out. The result must therefore be checked for both water production and separation. A successful cleaning test does not establish that repeated treatment will preserve those properties for the membrane’s whole working life.[1] [2]

The remaining target retains separation during prolonged fouling and cleaning cycles under the chosen feed and operating conditions. A recovered water flux alone does not show that pores remain selective or that repeated treatment preserves lifetime.[1] [2]

The aim is usable freshwater from salty water. Preserving separation through cleaning would let the membrane keep contributing to that supply over a longer working cycle, with water quality and replacement needs included in judging the result.[1] [2]

The decisive measurement is usable freshwater over the operating cycle, accounting for quality loss, cleaning and replacement.[1] [2]