Abstract: A control system controls a plurality of gas dehydrators in which each dehydrator has a dessicant bed. The system includes sensors sensing parameters of gas entering and leaving each dehydrator which provide corresponding signals. First valve apparatus connected to each dehydrator receives moist gas. Second valve apparatus connected to each dehydrator provides for a discharging of dehydrated gas from each dehydrator in accordance with control signals. Third valve apparatus connected to each dehydrator receives regeneration gas and provides the regeneration gas to a dehydrator in accordance with control signals. Fourth valve apparatus connected to each dehydrator provides for the discharge of regeneration gas after passage through the dehydrator in accordance with control signals.

Abstract: A low-pour fuel composition is prepared by blending with a gas oil a minor amount of a high asphaltene residuum, such as an Arabian Light 1050.degree. F. residuum, and from about 0.003 to about 0.50 weight percent of an oil-soluble copolymer which can be, for example, an ethylene-vinyl acetate copolymer or a block copolymer of the A--B--A type wherein the A block is derived from an ester of acrylic acid or methacrylic acid and an aliphatic alcohol and the B block is a copolymer of ethylene and vinyl acetate, etc.

Abstract: A topped crude oil is admixed with a hydrocarbon solvent and centrifuged in the presence of a brine carrier to produce a hydrocarbon solvent-fuel oil mixture and a brine-asphalt-fuel oil mixture, the latter mixture being recovered and admixed with a ketone solvent which effects emulsion breaking and extracts residual fuel oil, a ketone solvent rich phase being subsequently recovered and subjected to fractionation to separate the fuel oil from the ketone solvent, the latter being recycled for further usage.