Kenaf as a deep-bed filter medium to remove oil from oil-in-water emulsions

This study investigated the feasibility of deep-bed filtration using kenaf (agricultural fiber) media for the removal of oil from oil-in-water emulsions. Continuous flow, constant pressure filtrations were conducted using surfactant stabilized emulsions. Removal of oil and grease varied from 70 to 95% for 500 mg/L oil-in-water emulsion stabilized by surfactants. Oil removal was better for larger oil drops, finer media particles, higher filtration pressure, lower pH, cationic surfactant, and deeper media. Moisture contents and heating values of the spent media were determined. Moisture content decreased with increasing filtration pressure and decreasing particle size of the media. Heating values of the spent media increased with the volume of emulsion filtered. Heating values were high enough to produce surplus energy after accounting for the energy required for driving out the moisture. The results indicated that it may possible to dispose of the spent medium by combustion without further drying and extract net energy in the process.