Introduction

As the preceding chapters have indicated, the water supplied to a steam generating unit must be pure in order to prevent serious corrosion or scaling. Ion exchange had been the backbone of the high-purity water treatment industry, but with the improvement of membrane technologies, a variety of methods now exists to produce pure water. In most cases, some form of pretreatment is needed ahead of the makeup system to protect it from fouling, scaling, or microbiological contamination.