Economic Assessment of Inherently Safe Membrane Reactor Technology Options Integrated Into IGCC Power Plants

摘要

Pd/alloy-based (Pd/Cu, Pd/Au) membrane reactors embedded into Integrated Gasification Combined Cycle (IGCC) plants (IGCC-MR) would enable the storage and/or use of the energy value of H2 to produce electricity while the CO2 enriched retentate exit stream would be particularly suitable for high pressure CO2 capture-sequestration. There is undoubtedly a lack of operating experience associated with IGCC-MR plants because they have not yet been tested/operated on an industrial-scale. Therefore, sound process intensification principles/practices should be followed not only to enhance process system performance but also to ensure process safety and economic feasibility of an IGCC-MR plant. In a previous study [34], a comprehensive performance assessment of a lab-scale Pd/alloy-based membrane reactor was conducted and process parameters/operating conditions were identified with emphasis on process safety. However, inherently safe membrane reactors integrated into IGCC power plants would be more broadly used in practice only if the operating plant were demonstrated to be profitable. Motivated by the above considerations, a comprehensive process economic assessment framework for an inherently safe membrane Pd/alloy-based reactor integrated into an IGCC plant is proposed. In particular, a detailed Net Present Value (NPV) model has been developed to evaluate the economic viability of an IGCC-MR plant where the membrane reactor module design conforms to basic inherent safety principles. Sources of irreducible uncertainty (market, regulatory and technological) are explicitly recognized such as the power plant capacity factor, Pd price, membrane life time and CO2-taxes due to future regulatory policies. The effect of the above uncertainty drivers on the project's/plant's value is carefully taken into account by a Monte-Carlo simulation technique that enables the propagation of the above uncertain inputs through the NPV-model, and therefore, generate a more realistic distribution of the plant's value rather than a single-point/estimate that overlooks these uncertainties. The simulation results suggested that in the presence of (operational, economic and regulatory) uncertainties, inherently safe membrane reactor technology options integrated into IGCC plants become economically viable under key decision-making criteria such as expected NPV or confidence intervals associated with the above NPV distribution profile.