Abstract

Machine for removing residues such as oil, grease and diesel fuel spills from streets, parking lots and other paved surfaces. The machine comprises a mobile supporting vehicle having water supply and recovery tanks forming an integral part thereof. A steam generator is mounted on the vehicle for heating water from the supply tank to produce highly pressurized hot water and steam, and a hose and wand are connected to the steam generator for directing the pressurized water and steam against a surface to be cleaned. A pick-up wand and hose are connected to the recovery tank, and a vacuum pump is connected to the recovery tank for drawing water and residue from the surface through the pick-up wand and hose to the recovery tank. A filter is provided at the inlet of the recovery tank for removing particulate residue from the recovered water, and excess residue is bypassed around this filter to prevent the residue from backing up into the pick-up hose and clogging the hose when the filter is full. If desired, and agent such as a detergent, a degreaser or a coalescent can be added to the pressurized water to enhance the cleaning action.