The wetting of hydrophobic membranes caused by scaling phenomenon is the main issue that may constraint the successful applications of membrane distillation (MD) and membrane crystallization, especially during implementation of the Zero Liquid Discharge technologies. In this work, the submerged polypropylene modules were applied for separation of saturated NaCl solutions. The idea that membranes wetting can be reduced when the salts crystallize on the macrostructures covering the membrane surface is presented. To verify this idea, the effect of utilization of protective fibers layer assembled on the capillary membranes on the process performance was investigated. The permeate flux decreased 90% when the salt crystals covered membranes, thus the deposit was periodically dissolved. This operation accelerated the pore wetting and as a result the distillate conductivity increased from 5 to 200 μS/cm. On the contrary, the conductivity increased only to 20 μS/cm for membrane covered by fibers layer. In this case the salt crystalized mainly on the fibers surface, thus the salt dissolution did not wet the pores. The SEM studies confirmed that the fibers layer reduced the formation of salt deposits directly on the membrane surface. In the case of nonprotected membrane, a large amount of NaCl crystals were formed inside the membrane pores, which caused a mechanical damage of the membrane matrix. The scaling intensity and membrane wettability were studied during long-term tests, carried out over 2000 h. It has been found that the application of fibers layer allows to maintain the membranes durability despite intensive scaling phenomenon. In this case, it is essential to obtain mixing conditions in the boundary layer that ensure the feed flow inside the fibers layer.