Combined cycle heat recovery steam generators optimum capabilities and selection criteria

Abstract

The Heat Recovery Steam Generator is an integral and critical component of the Combined Cycle Power Plant. In the conceptual stage of the project it is very difficult to select the steam conditions for the optimized plant configuration. At this point most of the parameters are not well defined and since they are interdependent on each other, it is hard to optimize.

The paper presents discussion of what parameters are influenced by the type of circulation and how the selection should be made. The user can evaluate the critical parameters and select the circulation most advantageous for that particular plant.

This paper presents a method and an example of how the steam output of Heat Recovery System changes with the change in the steam conditions. The effect of auxiliary or supplementary firing in the boiler is also discussed.

Another dilemma these days is to determine whether a forced or natural circulation boiler is the best alternative.