CO2 Capture and Sequestration Options: Impact on Turbo-Machinery Design

Abstract

In the present climate of uncertainty about CO2 emissions legislation, owners and power plant planners are looking into the possibility of accommodating “add on” carbon capture and sequestration (CCS) solutions in their current plant designs. The variety of CCS technologies currently under development makes it a very challenging task. This paper initially discusses the more mature post-combustion CCS technologies, such as chemical absorption, and the associated equipment requirements in terms of layout, integration within the generating plant, and auxiliary power consumption. The analysis addresses both supercritical coal-fired as well as combined cycle plants. Plant configuration details and various operational scenarios are evaluated. The issues related to balance-of-plant systems, including water treatment, availability and redundancy criteria, are also offered. Continuing the paper presents a number of options for pre-combustion processes such as oxy-fuel combustion and integrated gasification combined cycle (IGCC) water-shift CO conversion to CO2. The impacts of several processes that only partially capture carbon are also evaluated from an engineering, procurement, and construction (EPC) contractor’s perspective as plant designer and integrator. Finally, the paper presents several examples of studies in development by Bechtel where a neutral but proactive technical approach was applied to achieve the best and most cost-effective solution.