20090166175 | SOLVENT EXTRACTION AND RECOVERY - Systems and methods for improving dense gas solvent extraction of a solute and recovery of the solvent are provided. A pressure of the solvent/solute mixture obtained from an extraction chamber is increased, e.g. with a pump, thereby providing the mixture above saturation conditions. The increased pressure provides greater solubility of the solute and less solvent being vaporized in a heat exchanger. A buildup of solute in the system is reduced, thus improving system longevity. Also, process conditions of the separation process are isolated from those of the extraction process. Accordingly, the process conditions for the separating process are maintained while the process conditions of the extraction chamber vary with ambient temperature, thus saving cost and energy. This isolation also provides an ability to use, in the gas recovery cycle, a heat pump that can be used for many applications and environmental conditions while still using a conventional refrigerant. | 07-02-2009 |