Chemical and Biological Engineering ETDs

Publication Date

Fall 11-17-1972


A design correlation is presented for the prediction of steady state product size distributions resulting from a continuous crystal­lizer, based upon a single experimental determination. This has been accomplished by the definition of a new parameter called the "degree of crystallization," which has been related to the experimental nuclea­tion and growth rates in a salting-out crystallizer. The correlation resulted from the detection of variations in the suspension density of the mother liquor which has previously been assumed constant in cer­tain power law models. The degree of crystallization has also been described in terms of dimensionless number, length and area moments which characterize a mathematical model to predict transient size distributions resulting from system upsets in residence time.

Included in this unsteady-state model is a unique phase space solution among the moments which has been confirmed by a digital com­puter solution. Computer simulation shows that the assumption of con­stant suspension density leads to an oscillatory behavior of the number, length and area moments. However, simulations in which the assumption was relaxed to permit variations in suspension density were characterized by a smooth self-regulatory operation. Separate studies conducted in a batch crystallizer of special design validates the assumption of McCabe's ΔL law in this work.

Document Type


Degree Name

Chemical Engineering

Level of Degree


Department Name

Chemical and Biological Engineering

First Committee Member (Chair)

George H. Quentin

Second Committee Member

Kenneth Edward Cox

Third Committee Member

Richard Emmett Dascher