摘要 |
A method for conditioning cooled used moulding sand retaining moulding sand binder in a mixer ( 1 ), wherein the cooled used moulding sand is heated to at least a minimum temperature, moisturized by providing water or water vapor through holes in an agitator and subsequently cooled in the mixer from the minimum temperature using the effect of a vacuum. The invention also includes an apparatus for practicing the method which includes a mixing container, a rotatable mixing agitator and a mixing agitator drive suitable for mixing moulding sand in the mixing container, apparatus for feeding components to be mixed to the mixer, apparatus for supplying hot water or hot water vapour to components in the mixing chamber through a plurality of holes in the agitator facing away from a direction of rotation of the agitator, apparatus for stopping the flows of hot water and vapour to the mixing chamber, apparatus for vacuum sealing the mixing container, apparatus for providing a vacuum in the mixing chamber after the flows are stopped to cool the contents of the mixing chamber and remove moisture by vacuum evaporation, and apparatus for removing mixed components from the mixing chamber. |