Abstract: Casting equipment for continuous or semi-continuous direct chill casting of metals, in particular the casting of billets or ingots of aluminum, has a mold cavity (4) with an inlet (2) that is upwardly open, an intermediate, inwardly facing and heat insulated overhang or hot-top (8), and an outlet with a vertically movable supporting device (5). A slit (10) supplies water to cool the molted metal. The wall in the mold cavity is wholly or partly constituted by a permeable material, whereby oil and/or gas are supplied through the permeable material to form an oil and/or gas layer between the metal and the wall of the mold to prevent the metal from coming into direct contact with the wall of the mold. The oil and gas are supplied separately through two independent, and, by means of a sealing element (14) or the like, physically separated rings or wall elements (12, 13).

Abstract: A hollow body, a rotor, with holes in the bottom and the side wall, is immersed down into a liquid and rotated with the help of a shaft suspended over the liquid.The liquid, which enters the rotor through the hole in the bottom, will, on account of the centripetal force, acquire a surface in the shape of a paraboloid of revolution. The centripetal force will throw the liquid out through the holes in the side wall, while new liquid will continuously enter through the bottom of the rotor.The shaft for the rotor can be hollow, and through this gas, solid or liquid materials can be added to the liquid.The invention makes possible the treatment in various ways of different types of liquid, from aqueous suspensions to molten metal.