The invention relates to a method and to a plant for processing a gas by means of a glycol solution wherein a feed comprising a gas, a glycol, water and salts is subjected to a first stage (5) of separating the gas from a liquid effluent and said liquid effluent is subjected to a dehydration stage (14) to recover a dehydrated liquid effluent, characterized in that the salts contained in the liquid effluent, dehydrated or not, are eliminated in a membrane separation stage (10) by means of a driving force generated by mechanical pressure difference on either side of a membrane of pore size ranging between 5 and 100 Angstrom. The invention also relates to the use of the method and of the plant for regeneration of a liquid compound of the glycol family used for hydrate formation prevention when using a natural gas.