Patent attributes
An asphalt recovery system may include an extractor, a desolventizer, and an evaporator. During operation, the extractor may receive a solvent and roofing waste and extract asphalt from the roofing waste with the solvent. The desolventizer may receive a solvent-wet solids stream from the extractor and vaporize solvent from the solvent-wet solids stream to yield desolventized solids. The evaporator may receive an asphalt-rich solvent stream from the extractor and vaporize solvent from the stream to produce a solvent stream and an asphalt stream. By configuring the evaporator to operate at a pressure above atmospheric pressure, the boiling point in the evaporator may increase as compared to operating the evaporator at a pressure below atmospheric pressure. In turn, this may keep the viscosity of asphalt within the evaporator less than 500 centipoise, which may improve heat transfer to the asphalt and prevent that asphalt from plugging the evaporator.
