A pressurized oxycoal combustion process is optimized for variable thermal loading (100%–30%). The steam expansion line behavior is accurately represented based on manufacturer data. Simulations with the nominal design and nominal operation are then performed with variable loads to determine...

A double-pinch criterion for closed feedwater heaters (FWH) of regenerative Rankine cycles is presented. The FWHs are modeled as counter-current heat exchangers. Thus, two potential pinch positions in the FWH exist: (i) at the exit of the bleed (drain) and (ii) at the onset of condensation. For...

Simultaneous multi-variable gradient-based optimization is performed on a 300 MWe wet-recycling pressurized oxy-coal combustion process with carbon capture and sequestration. A direct contact separation column is utilized for practical and reliable low-temperature thermal recovery. The models...

Simultaneous multi-variable gradient-based optimization with multi-start is performed on a 300 MWe wet-recycling pressurized oxy-coal combustion process with carbon capture and sequestration. The model accounts for realistic component behavior including heat losses, steam leaks, pressure drops,...

Simultaneous multi-variable gradient-based optimization with multi-start is performed on a 300 MWe wet-recycling pressurized oxy-coal combustion process with carbon capture and sequestration, subject to uncertainty in fuel, ambient conditions, and other input specifications. Two forms of flue...

The computation of lower bounds via the solution of convex lower bounding problems depicts current state-of-the-art in deterministic global optimization. Typically, the nonlinear convex relaxations are further underestimated through linearizations of the convex underestimators at one or several...

This article presents an analysis of the convergence order of Taylor models and McCormick-Taylor models, namely Taylor models with McCormick relaxations as the remainder bounder, for factorable functions. Building upon the analysis of McCormick relaxations by Bompadre and Mitsos (J Glob Optim...

A model is developed for an existing organic Rankine cycle (ORC) utilizing a low-temperature geothermal brine including the performance characteristics of the components. The model is validated with a set of 7200 operation data collected in one-year. The operation of the ORC is optimized...