Flexible process for treating solvent, such as monoethylene glycol, used in natural gas extraction

A process for purifying a hydrate formation inhibiting solvent, said solvent having a boiling point which is higher than that of water and, at least at one point in time, being mixed with water and salts, the process comprising:

• optionally, a pre-treatment of said solvent to be treated, said pre-treatment separating at least a portion of the hydrocarbons, condensates, and gases, and said pre-treatment optionally comprising adding a chemical neutralization agent;
• determining whether the quantity of salts in a treated mixture is above, equal to, or below a precipitation threshold;
• a reclaiming phase carried out when the quantity of salts in said solvent, which has optionally been pre-treated, is equal to or greater than the precipitation threshold in the treated mixture;
• said phase comprising a vacuum flash, operating at a pressure which is below atmospheric pressure and at a temperature which is below the degradation temperature of the solvent, by which a stream of solvent containing salts and a vaporized stream of solvent and water are obtained, said stream of solvent and water being vacuum distilled at a pressure which is substantially equal to that prevailing in said vacuum flash in order to separate the water and recover a stream of purified solvent, the salts being separated from said stream of solvent containing the salts, then the solvent obtained being recycled to the flash;
• wherein when said quantity of salts in the treated mixture is below a precipitation threshold, stopping the reclaiming phase and carrying out a phase termed regeneration;
• said regeneration phase comprising releasing the vacuum, the solvent to be treated, which has optionally been pre-treated, undergoing a flash step, operating at a pressure greater than or equal to atmospheric pressure and at a temperature which is below the degradation temperature of the solvent, by which a first stream of purified solvent and a stream of solvent and water are obtained, said stream of solvent and water being distilled under a pressure substantially equal to that prevailing in said flash, the water being separated and a second stream of purified solvent being obtained, said second stream being mixed with said first stream and/or recycled to said flash.