Chapter 6 - Alternate Semi-Aqueous Precision Cleaning Techniques: Steam Cleaning and Supersonic Gas/Liquid Cleaning Systems

Abstract

This chapter describes two alternate semi-aqueous cleaning methods, precision steam cleaning and supersonic gasliquid cleaning. Steam can be a practical and environmentally friendly method to clean without the use of solvents. Vapor steam cleaning has been used in a variety of applications from household to industrial to military to medical. Simply boiling water can generate steam; however, it is the combination of temperature and pressure that makes steam cleaning effective. A steam cleaner is a highly beneficial piece of equipment for all home, commercial, and industrial applications requiring sanitizing, disinfecting, and cleaning capabilities in a single machine. Two alternate semi-aqueous cleaning techniques have been developed for various precision cleaning applications. Vapor steam cleaning employs dry superheated steam to remove surface contaminants. It is a low-cost, effective method for precision cleaning and for decontamination of microbially contaminated surfaces. Supersonic gas-liquid cleaning is based on accelerating the cleaning liquid, suspended as droplets in a gas stream, to supersonic velocities through a converging-diverging nozzle. The gas–liquid mixture has the kinetic energy to very effectively remove surface contaminants. This method can also be used for cleanliness verification. Both methods use very low volumes of aqueous liquids and are viable alternatives to solvent cleaning in many applications.