Abstract: The invention comprises a positive fluid displacement apparatus of the scroll-type described as a fluid compressor in the exemplary embodiment. The embodiment has single fixed and movable scroll elements in which the latter describes orbital movement relative to the former to form variable volume pockets therebetween which move from an inlet to an outlet. To accommodate for a difference in thermal expansion between the innermost and outermost zones of the apparatus, the scroll elements are formed with varying thicknesses along the lengths thereof. Accordingly, centrally of the apparatus, whereat an exhaust port is formed, scroll element thicknesses are greatest, the compressed fluid is most dense, and the thermal expansion is least, the elements define close, substantially sealing minimum clearances of a given measure.

Abstract: A method and machine are disclosed herein for cleaning and restoring sand beaches which have become contaminated by oil spills. The machine travels on the beach and sprays liquid nitrogen onto the contaminated area, thereby solidifying the oil and sand mixture so that the mixture can be separated from the underlying uncontaminated sand and be efficiently removed from the beach and transported to a remote site for disposal or further treatment.

Abstract: An improved method and apparatus are disclosed herein for cryogenically cleaning and restoring sandy beaches which have become contaminated by oil spills. In the method, a mixture of particulate, pulverized and recycled rubber and wood fines is applied to the contaminated area for absorbing the oil prior to cryogenic treatment. The absorption of the oil by the particulate rubber and wood enhances the solidification during the cryogenic treatment. In the apparatus, a hopper is mounted to a beach cleaning vehicle forwardly of a liquid cryogen spray head. The hopper is constructed to receive and discharge particulate absorbent before the contaminated area is contacted by the liquid cryogen.

Abstract: A method and machine are disclosed herein for cleaning and restoring sand beaches which have become contaminated by oil spills. The machine travels on the beach and sprays liquid nitrogen onto the contaminated area, thereby solidifying the oil and sand mixture so that the mixture can be separated from the underlying uncontaminated sand and be efficiently removed from the beach and transported to a remote site for disposal or further treatment.

Abstract: A method for removal of layers of organic material built up on a support for articles during surface coating and treating comprising applying a liquefied inert gas to the support and/or preferably to the built up layers of organic material to cause embrittlement of the organic material and lessening of the bonded relation between the support and the built up layers, and then separating the embrittled built up layers from the support by abrasion of impact.