Dehydration of turbine engine lubricant oil using cellulose hydrogel

Contamination of oils by water is a recurring problem in the industry and can damage engines and equipment. Oil dehydration systems with hydrogels have shown promise for the removal of free, soluble, and emulsified water. This work evaluates, in an unprecedented way, the dehydration of turbine lubricating oil using a cellulose hydrogel. The synthesis of the hydrogel was confirmed by the formation of specific functional groups. The hydrogel was characterized through high-resolution SEM, EDS, FTIR, BET, TGA, DVS and swelling degree. The oil was evaluated regarding its composition and physicochemical properties. The performance of the hydrogel in the treatment of water-in-oil emulsion was analyzed in batch and continuous flow systems. A fixed bed apparatus was specially designed and sized according to the industry's specifications to simulate on-site application. The batch treatment was evaluated using orbital and full tumbling inversion mixing systems, both reaching removal efficiency of around 47 %. Mixing by full tumbling allowed greater stability of the emulsion and control of the water concentration, but it required a longer time to enable adequate water uptake by the hydrogel. The efficiency of the hydrogel in the continuous flow system was affected by retention time and inlet water concentration. With a retention time of 12 min, it was possible to treat 1 L of oil, reducing the water concentration from 412 ppm to 197 ppm and the turbidity from Haze 6 to Haze 1. Thus, the cellulose hydrogel was efficient in dehydrating turbine lubricating oil, opening up the possibility of expanding its use to industrial facilities. [Display omitted] •First report of lubricant dehydration using hydrogels.•Use of a natural and biodegradable polymer to treat water-in-oil emulsion.•Desing of a new hydrogel fixed-bed system with radial oil distribution.•Water content was reduced from 412 to 197 mg.kg−1 under continuous lubricant flow.•Novel hydrogel treatment allowed meeting specifications of water content in oil.