ABSTRACT
This chapter discusses primarily the on-line viscosity measurement of slurries. It also introduces an optical method for detecting the mixture quality of powders. The chapter also discusses motion sensors applicable to powder feeders. The viscosity of slurries depends on various factors, such as particle volume fraction in a slurry, size distribution of suspended particles, particle shape, and electric charge on particles. Measurement of viscosity types are capillary viscometer, falling-ball viscometers, and coaxial cylinder viscometers. The measuring system should be set in a constant-temperature bath as in the case of the capillary viscometer. The measurement of powder composition is usually carried out by use of off-line instruments such as an x-ray fluorescence analyzer after sampling the process powder. Qualities of powder mixtures can also be evaluated based on a colorimetric technique. The piezoelectric motion sensor detects vibrations caused by the rotation of the motor or feeder system through deformation of the piezoelectric crystal.
