A stirrer device, especially for the mixing of a fluid with at least one other fluid, includes at least one fluid dispersing unit able to turn about an axis of rotation, having at least one exit opening for at least one fluid discharge, and the stirrer device has at least one optimization unit, which in at least one operating state increases at least a differential pressure at the exit opening.

In an embodiment, a reactor for carrying out a melt transesterification reaction at a reactor temperature of 160 to 300 C. and a reactor pressure of 5 to 200 mbar, comprises a cylindrical tank comprising a top, a side, and a bottom, wherein the bottom is convex, extending away from the top; a stirring shaft disposed within the cylindrical tank along an axis thereof so that it is rotatable from outside of the cylindrical tank; an impeller extending from the stirring shaft in the cylindrical tank and comprising a plurality of blades; a reactant solution inlet; a reaction solution outlet; and an externally located heat exchanger in fluid communication with the cylindrical tank via a recirculation stream and a heated stream. The reactor can be used for the polymerization of a polycarbonate oligomer.

The present invention relates to a rotor that comprises a series of shaped rotor blades whose circumferential section forms a standard NACA four-digit airfoil. Said rotor can be inserted in a stirring device that also comprises a stator, on whose inner surface shaped stator blades are positioned, whose circumferential section forms a standard NACA four-digit airfoil.

The invention relates to a rotary shaft for processing foodstuffs, the rotary shaft has a rotation axis and the rotary shaft comprises at least one tool which extends along the rotation axis. The tool has an airfoil profile such that the tool comprises a leading edge, a trailing edge, an upper surface and a lower surface. Further, the tool comprises at least one fluid channel between the mean camber line of the airfoil profile and the upper surface of the tool.

An agitator device, in particular a draft tube agitator device, with at least one stirring unit, which is rotatable around a rotary axis, which is configured for conveying a fluid in an axial conveying direction and which includes at least one rotor blade element, the projection of said rotor blade element onto a plane that is perpendicular to the rotary axis having an at least substantially circular-arc-shaped outer contour,

the rotor blade element comprises at least one first region, which is situated in a blade plane and is at least substantially planar, and includes a second region, which is curved out of the blade plane.

The present invention relates to a rotor that comprises a series of shaped rotor blades whose circumferential section forms a standard NACA four-digit airfoil. Said rotor can be inserted in a stirring device that also comprises a stator, on whose inner surface shaped stator blades are positioned, whose circumferential section forms a standard NACA four-digit airfoil.

A method and apparatus for aerating wine or spirits to reduce the astringency, or bitterness of wine or spirits. Astringency is often a result of tannins in wine or spirits, particularly noticeable in full bodied red wines. Aeration causes oxygen to dissolve in wine or spirits where it will oxidize tannin compounds, thereby reducing the astringent flavor. The method employs an apparatus wherein a hand held unit having a battery, switch or button, electrical wiring and electric motor cause rotation of a drive-shaft and aeration head. The aeration head is immersed in wine or spirits, the switch activated causing rotation of the aeration head creating a plurality of fine air bubbles resulting in large wine or spirit to air surface area simultaneous with stirring to ensure uniform oxygenation and aeration of wine or spirits throughout the container. The process may be extended until the desired reduction in astringency is achieved.