In-Line Testing of Novel Filter Media for Oil-Water Mixtures

摘要

Proof-of-concept of novel, nano-fibrous, highly selective and inexpensive filter media for in-line oil-water separation is established. Two kinds of filter membranes were fabricated, hydrophobic-oleophilic membrane and hydrophilic-oleophobic membrane. Three housing configurations were designed, namely dead-end, crossflow (inside-out) and "outside-in" crossflow, incorporating the filter membranes, and tested in a multiphase flow loop. The recommended design, the "outside-in" crossflow configuration, consisted of a 2" diameter outer pipe and an inner porous tube of 3/4" diameter, around which the filter membrane was wrappedl.;Experimental runs were conducted with only the hydrophilic-oleophobic filter for water-continuous flow with low oil concentrations (water cleaning). The collected experimental data included pressure drop, permeate flow rate and purity. Values of permeate flow rate and pressure drop were averaged over the duration of the experiments, which was about 5 minutes, constituting the "initial average" of the permeate flow rate and the corresponding pressure drop.;The "outside-in" crossflow filter housing configuration showed the best performance as it provided robustness and durability for the filter membrane. Twelve experimental runs were conducted with the "outside-in" housing configuration for mixture velocities of 0.038 m/s, 0.055 m/s and 0.066 m/s, and oil concentrations of 0.6%, 0.83%. 1.1%, 7.9% and 9.1%.;Permeate samples were analyzed for oil content and showed high average separation efficiency of 98 + 2%. The permeate flux across the filter cartridge ranged between 0.0739 (L/h)/cm2 to 0.216 (L/h)/cm2 owing to the low pressure drop. Oil concentration in permeate water samples showed consistently increasing trend with an increase in inlet oil content, while maintaining high separation efficiency for all runs. The pressure drop across the membrane under flowing conditions ranged from 0.35 psid to 0.6 psid for flow rates between 0.1 L/min and 0.29 L/min, respectively. The filter membrane breakthrough pressure was 0.35 psid.