Vegetable oil as a solvent for removing producer gas tar compounds

• Soybean and canola oils performed similarly as solvents in removing tar compounds.
• Oils were tested using a bench scale wet packed bed scrubbing system.
• Bed height and solvent temperature had significant effects on tar removal.
• Solvent flow rate did not have a significant effect on tar removal.
• Bed height, temperature and flow rate had significant effects on pressure drop.

The objective of this study was to evaluate the performance of vegetable oil as a solvent in a wet packed bed scrubbing system for removing model producer gas tar compounds. Solvent type, column bed height, solvent temperature and solvent flow rate were varied to assess the performance in terms of tar removal efficiency. Soybean and canola oils were used as solvents. Benzene, toluene and ethylbenzene were used as model tar compounds. Testing was conducted using a bench scale packed bed column, 5.25 cm diameter by 1.1 m height, filled with 6-mm raschig rings as packing material. Statistical analysis showed that soybean and canola oils provide comparable removal efficiencies of tar compounds. The analysis also revealed that bed height and solvent temperature had highly significant effects on tar removal efficiencies. Bed height, solvent temperature and solvent flow rate had highly significant effects on liquid holdup and pressure drop across the column.