Jean W. Beeckman

A controllable vibratory calciner for processing high‐temperature superconductors and other ceramic powders

A novel vibratory calcination apparatus is described, that enables reactant powders to be heated at or above their sintering temperatures without excessive agglomeration. In addition, the vibration‐induced fluidization leads to greatly improved gas‐solid contact, which can significantly speed up reactions that are limited by the ingress or egress of gases. Unlike its gas‐fluidized counterpart, the vibratory calciner does not lead to excessive loss of fines. Vibration is generated by means of a function generator‐amplifier‐loudspeaker voice coil system, which allows amplitude, frequency, and time dependence of frequency to be precisely controlled. The system has been used extensively in the laboratory for the calcination of high‐temperature superconducting powders, where its use has led to greatly reduced calcination times and a much lower degree of agglomeration in the finished material.