Abstract: A hot aqueous waste, containing solids, such as tailings from the hot water extraction of bitumen from tar sands, is contacted with air to increase the heat and moisture content of the air, followed by contacting the heated and moisturized air with water to condense moisture from the air and increase the heat content of the water, with the heated water containing condensed moisture being employed as make-up hot water in the extraction. Water recovery can be further increased by subjecting at least a portion of the tailings, prior to contact with air, to an evaporation procedure wherein heat requirements are provided by indirect heat transfer with steam. Evaporate and condensed steam are employed in the extraction.

Abstract: A hot aqueous waste, containing solids, such as tailings from the hot water extraction of bitumen from tar sands, is contacted with air to increase the heat and moisture content of the air, followed by contacting the heated and moisturized air with water to condense moisture from the air and increase the heat content of the water, with the heated water containing condensed moisture being employed as make-up hot water in the extraction. Water recovery can be further increased by subjecting at least a portion of the tailings, prior to contact with air, to an evaporation procedure wherein heat requirements are provided by indirect heat transfer with steam. Evaporate and condensed steam are employed in the extraction.

Abstract: Volatile liquid, such as benzene, isoprene, cyclopentadiene, butadiene present as a vapor in a blanket gas released from a storage zone for the liquid is absorbed from the gas by use of an absorption oil, followed by contacting of the rich absorption oil with an immiscible extraction solvent in an amount much less than the absorption oil to extract absorbed volatile liquid and provide a lean absorption oil. The volatile liquid is recovered from the extraction solvent, for example, by stripping. By recovering the volatile liquid from the small amount of extraction solvent, rather than the absorption oil, heating and cooling duties are decreased.

Abstract: In the hydrotreating of pyrolysis gasoline, recycle effluent is treated to separate the more volatile components therefrom, prior to recycle, to thereby increase the hydrogen partial pressure of the hydrotreating. In this manner, total pressures can be reduced to correspond to the pressure of the available hydrogen gas, while retaining the kinetic benefits of increased partial pressures.