Multi-Section Centrifugal Compressors: Compound Versus Back-to-Back Configuration

The requirement of a multi-section centrifugal compressor can potentially be satisfied with two distinct configurations: a compound design, and a back-to-back design. Both configurations can offer unique advantages to the end-user and the compressor OEM.

This presentation aims to inform the process-licensor or equipment purchaser of the benefits of the two designs. The audience will be introduced to the general process flow path of the two designs with a description of the components of interest. A comparison of the internal leakage paths, leakage quantities, main-casing seal differences, thrust considerations, and thermal gradients will be presented. Though these attributes are typically the primary concern of the compressor OEM, an explanation will be provided to qualify their effect on efficiency- a topic of importance to all parties.

There may also be a circumstance in which the purchaser will require one configuration or the other. This instance will be presented with a description of how a particular configuration can satisfy the requirement.