"... women with the land... sit inside the temple of love and have intercourse with a few stranger... the men pass to make their choice. It matters not what are the amount of cash; the women won't refuse, for your were a sin, the money being by this act made sacred. After their intercourse she has made herself holy inside sight of the goddess... " 1 Used motor oil that has impurities and dirt is fed into a centrifuge. The centrifuge carries a rotor that spins an extremely high RPM (revolutions each and every minute) and yes it pushes the impurities towards the wall in the container that houses the rotor. This works because the mass in the impurities is greater than the mass of the oil particles. Appropriate extraction methods are widely-used in order that impurities as well as the clean motor oil are properly separated, and also the oil is ready to be re-used. These filtering systems are also right for use with small-scale biofuel setups to remove any impurities.