ABSTRACT
Desorption can be carried out in several ways, the most important of which are desorption by a stream of inert gas, desorption by temperature rise, and desorption by pressure reduction. If the aim of the desorption process is the recovery of the solute gas rather than the purification of the liquid, steam is commonly employed in place of air on account of its ease of separation from the solute gas by condensation. The chapter examines some general design considerations, desorption involving the removal of acid gases from process gas streams, and desorption by pressure reduction as occurs in certain synthesis loops. It focuses on specific and distinctive features of the process design of desorption systems. Some examples of the use of pressure reduction as a degassing device are found in the methanol, ammonia, and Oxo syntheses—all of which involve gaseous reactants at relatively high pressures.
