Combined Production of Hydrogen and Power from Heavy Oil Gasification: Pinch Analysis, Thermodynamic and Economic Evaluations

Integrated Gasification Combined Cycle (IGCC) represents a commercially proven technology available for the combined production of hydrogen and electricity power from coal and heavy residue oils. When associated with CO2 capture and sequestration facilities, the IGCC plant gives an answer to the search for a clean and environmentally compatible use of high sulphur and heavy metal contents fuels, the possibility of installing large size plants for competitive electric power and hydrogen production, and a low cost of CO2 avoidance. The paper describes two new and realistic configurations of IGCC plant fed by refinery heavy residues and including a CO2 capture section, which are proposed on the basis of the experience gained in the construction of similar plants. They are based on oxygen blown entrained bed gasification and sized to produce a large amount of hydrogen and to feed one or two gas turbines of the combined cycle unit. The main thermodynamic and technological characteristics of the total plants are evaluated focusing on the heat integration between syngas cooling and combined cycle sections. Moreover, the overall performance characteristics and investment cost are estimated to supply a reliable estimate for the cost of electricity, given a value for the hydrogen selling price.