Jake Nease

Chapter 6 – Processes and simulations for solvent-based CO2 capture and syngas cleanup

Abstract This chapter provides a detailed methodology for constructing steady-state flow sheet simulations of common solvent-based CO2 and H2S capture processes using popular commercial software. Detailed examples are provided for solvents such as monoethanolamine, methyldiethanolamine, DGA, Piperazine, Selexol, and Rectisol in a variety of applications, such as integrated gasification combined cycles, gas-to-liquid plants, coal-to-liquid plants, natural gas combined cycles, and sweet and sour gas cleaning. Tutorials are provided for Aspen Plus, Aspen Hysys, BRE ProMax, and Invensys Pro/II, with screen captures, step-by-step guides, and expert advice designed to make the construction of these notoriously difficult simulations as easy as possible. Twenty-one different examples are discussed, with completed simulation files available for download for the reader.

Application of a Multiple Time-Scale Rolling Horizon Optimization Technique for Improved Load-Following of an Integrated SOFC/CAES Plant with Zero Emissions

Abstract In this work, a two-stage rolling horizon optimization (RHO) framework is formulated and applied to a SOFC/CAES integrated power plant to achieve optimal year-round peaking power with zero emissions. The two-stage RHO exploits the modular nature of the upstream SOFC power island to make safe and reliable changes to the plant’s nominal operating point to follow seasonal demand trends in the first stage, and uses the CAES system to match hourly fluctuations in demand. Results for a simulated year using historical demand data show that the two-stage RHO improves load-following by as much as 90% as measured by the integrated squared error between supply and demand.

Integrated fault diagnosis and robust safe-parking for fault-tolerant control of nonlinear systems

In this work, we consider the problem of fault diagnosis and fault-handling for nonlinear systems subject to actuator faults. A model-based fault diagnosis scheme is proposed, which can not only identify the failed actuator, but also estimate the magnitude of the fault. With the aid of the fault diagnosis design, the safe-parking framework for fault-tolerant control is extended to handle the case where an actuator seizes at an arbitrary position. The efficacy of the proposed framework is demonstrated through a chemical reactor example.