Abstract: A heat pump device in which a temperature difference is established between two heat exchangers by inducing cyclical expansion and compression pulses in a working fluid vapour or gas which passes through an adsorbent porous solid located between the heat exchangers.

Abstract: A closed-loop biomass extraction apparatus using HFC solvents including an extraction vessel, an evaporator for the solvent, a compressor and a condenser connected in series in a closed loop extraction circuit; a solvent recovery loop constituted by a bypass line; a plurality of flow control valves that are selectively operable for connecting the solvent recovery loop in parallel with the closed loop extraction circuit; and at least one container containing an adsorbent for organic contaminants and a desiccant, the container being connected in the solvent recovery loop to which solvent in the extraction circuit may be supplied through selective operation of the flow control valves whereby solvent used in the extraction circuit may be supplied through the adsorbent and the desiccant.

Abstract: In the field of biomass extraction, there is a need for effective removal of solvent from spent biomass material. An apparatus for removing solvent residues includes a vessel (11) for containing biomass; a steam source (19) for supplying steam to contact the biomass; and a separator (24) for separating solvent from steam that has contacted the biomass. The disclosure also includes a method of use of the apparatus.

Abstract: Apparatus and methods for reducing residual solvent levels in extracted biomass that is contaminated with HFC solvent that includes sparging the biomass extract with a solvent stripping gas such as air or nitrogen are disclosed. Apparatus for carrying out the method include a vessel (12;25) containing extract (26) and a source of the gas. The source may be in the form of a moveable, hollow wand (27) having a sparging gas outlet; or a fixed gas inlet (30) for bubbling the gas through the extract (26).

Abstract: In a closed-loop biomass extraction apparatus (10), strategies for purifying HFC solvents used therein include: (i) contacting an adsorbent and a desiccant, e.g. in a container (26) with contaminated HFC solvent branched from the main flow loop; and, optionally, (ii) washing contaminated HFC solvent with water, e.g. in a vessel (34) to separate a co-solvent or entrainer, such as ethanol, thereform.

Abstract: In the field of biomass extraction, there is a need for effective removal of solvent from spent biomass material. An apparatus for removing solvent residues includes a vessel (11) for containing biomass; a steam source (19) for supplying steam to contact the biomass; and a separator (24) for separating solvent from steam that has contacted the biomass. The disclosure includes a method of use of the apparatus.

Abstract: In the field of biomass extraction, there is a need for effective removal of solvent from spent biomass material.

Abstract: An apparatus (10′) for extracting biomass includes an extractor (11), evaporator (12), compressor (13) and condenser (14) connected in series by pipework (17) to define a closed loop extraction circuit. A transfer line (18) selectively supplies hot solvent vapor from the outlet side of the compressor (13) to the interior of the extractor (11), where the solvent vapor heats the biomass. This causes stripping of solvent from the biomass. The transfer line (18) includes control elements (19,20) for controlling the flow of solvent vapor.

Abstract: An apparatus for extracting biomass includes a closed loop circuit having an extraction vessel (11), an evaporator (12), a compressor (13), a condenser (14) and (optionally) a storage reservoir (15) operatively connected in series. A pumped recirculation loop (20) recirculates a portion of the output of the extraction vessel (11) for further contact with biomass. One or more modifiable resistances to flow (12;23) control the flow of solvent around the recirculation loop (20) and the main closed loop.

Abstract: In a closed-loop biomass extraction apparatus (10), strategies for purifying HFC solvents used therein include:

Abstract: A method of reducing residual solvent levels in extracted biomass that is contaminated with HFC solvent includes sparging the biomass extract with a solvent stripping gas such as air or Nitrogen.

Abstract: Apparatus and methods for reducing residual solvent levels in extracted biomass that is contaminated with HFC solvent that includes sparging the biomass extract with a solvent stripping gas such as air or nitrogen are disclosed. Apparatus for carrying out the method include a vessel (12;25) containing extract (26) and a source of the gas. The source may be in the form of a moveable, hollow wand (27) having a sparging gas outlet; or a fixed gas inlet (30) for bubbling the gas through the extract (26).

Abstract: An apparatus (10′) for extracting biomass includes an extractor (11), evaporator (12), compressor (13) and condenser (14) connected in series by pipework (17) to define a closed loop extraction circuit. A transfer line (18) selectively supplies hot solvent vapor from the outlet side of the compressor (13) to the interior of the extractor (11), where the solvent vapor heats the biomass. This causes stripping of solvent from the biomass. The transfer line (18) includes control elements (19,20) for controlling the flow of solvent vapor.

Abstract: A closed loop apparatus (10) for extracting biomass includes an evaporator (42) and a condenser (43) directly connected to one another, without an intermediate compressor. An optional pump (14) moves liquid solvent between the evaporator (42) and compressor (43) and provides a hydrostatic head for the closed loop circuit.

Abstract: A condenser (20) includes within its shell (22) a reservoir (22b) for condensed solvent used in biomass extraction. The reservoir (22b) supplies liquid solvent (23) to an extraction vessel (11) via an inverted lute (30). The height of the uppermost part (35) of the lute (30) determines the level of liquid (28) in the reservoir. In an embodiment the height of the uppermost part (35) is adjustable, to control the liquid level.

Abstract: A non-azeotropic refrigerant is described comprising (A) carbon dioxide (CO.sub.2), (B) pentafluoroethane (R-125), (C) 1,1,1-trifluoroethane (R-143a) and (D) chlorodifluoromethane (R-22).