Chapter 1 - WHY WRITE THIS BOOK?

Abstract

This chapter discusses the history of impinging streams (IS) and its application in engineering. Impinging streams is a unique and multipurpose configuration of a two-phase suspension and provides a tool for intensifying transfer processes in heterogeneous systems. The field of IS has made gains since 1980 by exploring the following processes—drying of solid particles, solid–solid and gas–gas mixing, absorption and desorption of gases from liquids in the presence and absence of a chemical reaction, combustion of gas and coal, calcination of phosphate ores, creation of emulsions, liquid–liquid extraction, dissolution of solids, ion exchange, dust collection and granulation, as well as evaporative cooling of air. Since then various approaches have been adopted in modeling IS: (1) A simplified approach considered the flow behavior of a single particle and incorporated basic correlations of heat and mass transfer. (2) A more sophisticated approach, applying Monte-Carlo simulation, made it possible to incorporate the effect of interparticle collisions in the calculations. Thus, it was possible to investigate some processes in which this effect is significant, as well as to predict some typical IS behavior. (3) Applying the Markov chain probability approach made it possible to investigate the residence time distribution of the particles in IS reactors, as well as to simulate various processes and describe their characteristic behavior.