High Efficiency Blower Under 50hp Retrofit

The blower power depends upon three variables: flow rate; pressure, and efficiency. The design of an energy efficient blower depends upon two main factors: shape of impeller and shape of blower housing that minimize pressure losses. The conventional blower’s (i.e., incumbent technology) efficiency is typically below 60%, depending upon pressure and flow rate requirements. The new-generation blowers with improved impeller design and the blower housing is about 70% efficient (as high as 79% from limited number of manufacturers). This project will attempt to identify if we can deploy an energy efficient blowers with an improved process design that would save energy.

This project focuses on the “Re-evaluation and implementation of an alternative production process design” for an open-blowing process. More specifically, this project addresses the technical feasibility of replacing a blower system under 50 horsepower (hp) with a more energy efficient one. Southern California Edison (SCE) conducted a field assessment at a styrene production site, Americas Styrenics, LLC located in Torrance, California. This site was selected because it had dedicated blowers for an open-blowing application (i.e., the removal of water from its products). Its production level was relatively constant throughout the year, and it ran 24 hours a day, over 50 weeks per year. The customer chose a styrene production line, with a 25 hp blower system, for the technical evaluation. Because of this evaluation, an alternative system was designed that consisted of a 7.5 hp centrifugal blower, two sets of engineered air knives, and a flexible conduit. The new blower system was then redesigned, with consideration given to the existing 25 hp blower’s discharge pressure and airflow rate. Baseline system tests were conducted in May and November 2011, and demonstrated that significant energy savings could be achieved by replacing the existing blower system with an energy efficient one.