Abstract

A method and apparatus for controlling the volume or quantity of components being fed into a continuous, static mixing head are based upon the phenomenon of concentric, thin layers meeting with high velocities in a circular and free-flowing mixing zone (14). The regulating method can be adapted to various embodiments of mixing heads, and can be used for raw material combinations comprising powders, liquids, gas vapor or air, as well as mixing a small quantity into a large quantity. The thin layers are formed and controlled in conical, annular nozzles between fixed cone surfaces (12, 25, 27) and axially movable cone surfaces (11, 28, 29), where the movements are transferred from displacement members (15, 34) on the outside of the mixing head which regulate nozzle orifices and amounts or volumes. One situation regulates a mixing head where a downward directed powder layer in the mixing zone meets with obliquely downward directed liquid layers from the inside and the outside. In the mixing zone, mixing and discharge occurs instantaneously. A mixing process for cement related products uses three mixing heads connected in series, with different products after each respective steps. The mixing heads are compact. Capacities of up to 150 m3 /hour can be achieved with a mixing zone diameter smaller than 200 mm.