The model of the bulk crystallization in a cascade of well-mixed vessels with a continuous removal of solid particles and a recycle is suggested. The system of integro-differential equations describing dynamics of the crystal size distribution density and the supersaturation in apparatuses composing the cascade is obtained. Characteristics of neutral stability of stationary crystallization processes as well as self-oscillating regimes originating as a;result of instability are studied in detail. An opportunity for application of external periodic influences for changing conditions of the stability break and for improving the technological characteristics of crystallizers is revealed.