Abstract: A cement premixer includes a treatment container having a treatment space. The treatment container has a side wall and a bottom, and at least one stirring unit at least partially projecting into the treatment space. The stirring unit is connected to a shaft having an axis of rotation. At least one ultrasonic probe projects at least partially into the treatment space. At least one ultrasonic oscillator applies ultrasound to the at least one ultrasonic probe. The cement premixer has at least one first introduction opening for the supply of cement and an outlet for the flow supply line for feeding a cement suspension provided by the cement premixer into a concrete-mixing device.

Abstract: A device for producing a concrete includes a cement premixer for mixing a cement suspension, the cement premixer having an ultrasonic probe for preparing a cement suspension, a crystallization tank arrangement with the first crystallization tank, for increasing the early strengths of the concrete, and a concrete mixer for producing a concrete mixture from the premixed cement suspension, in particular with the addition of aggregates.