Device for mixing cement slurry and method and apparatus for producing cement slurry

A device for mixing cement slurry comprising a containment structure (2) which delimits a mixing chamber (3) divided by a pierced wall (10) into an inner part (11) and an annular outer part (12), a centrifugal impeller (14) fixed to a first end (5) of a driving shaft (4) and positioned in the inner part (11) of the mixing chamber (3); the containment structure (2) also comprising an inlet (8), facing the inner part (11) and to which a feed duct (19) is joined; the feed duct (19) and/or the inlet (8) being shaped in such a way as to form a cross-section increasing towards the centrifugal impeller (14). Also provided is a method for producing cement slurry wherein a mixture of water and cement is fed to a centrifugal impeller (14), which pushes it through a fixed pierced wall (10) which surrounds the centrifugal impeller (14), and wherein upstream of the centrifugal impeller (14), an increase in the pressure of the mixture is generated.