Screw Type Steam Compressors for Mechanical Vapor Recompression (MVR) Systems

Abstract

In processes of evaporation, distillation or drying, steam is used at different pressure and temperature levels. Such processes are found in the chemical, pulp/paper, fiber and several similar industries. These industries use large volumes of boiler generated steam, of which, very little is recovered after use because the pressure has been reduced to near atmospheric conditions. As a result, this "unusable" steam is vented to the environment while fresh steam is generated. A reversal of this cycle could be a potential source of cost savings in an era when the cost for generating energy is on the rise and represents a major portion of the cost of the raw materials. The technology is available today to prevent such loss of resources by recompressing the low pressure steam to a usable pressure for reinjection into the process stream. Mycom has developed, designed and installed two large MVR systems using screw compressors: one for a brewery and the other for a whiskey plant. This paper discusses the system aspects that presented challenges to Mycom. The economic benefits being realized will be discussed.