Exergoeconomic analysis and performance assessment of hydrogen and power production using different gasification systems

In this paper, we investigate three different gasifiers for hydrogen production, namely, downdraft gasifier (DG), circulating fluidized bed gasifier (CFBG) and plasma gasifier (PG) as taken from the literature under Cases 1-3, respectively. These cases are then modified for cogeneration of hydrogen and power. We use the specific exergy cost (SPECO) method to calculate exergy-related parameters and display cost flows for all streams and components. The case studies are selected from different countries. We study how flow rates of streams cost and hydrogen unit costs change if these facilities operate in Turkey. The process life time is considered 15 years, and the inflation rate and energy inflation rate are taken from the Central Bank of the Republic of Turkey as 8.91% and 19.25% while unit energy, water and biomass costs are taken 31.38 $/GJ, 4.59 $/t and 35.42 $/t for Turkey, respectively. The electric power requirements are calculated to be 0.0915, 12.53 and 23.26 MWe for DG, CFBG and PG, respectively. In Cases 1-3, the electric power generated by the systems are 0.144 MW, 1.17 MW and 3.88 MW, respectively and may be sold to the national grid with cost rates of 31.8 $/h, 258.39 $/h and 856.88 $/h. In the systems, the hydrogen production rates and costs per unit mass are obtained to be 0.004 kg/s, 0.521 kg/s and 0.155 kg/s and 1.16 $/kg, 3.33 $/kg and 2.45 $/kg for the DG, the CFBG and the PG, respectively. (C) 2012 Elsevier Ltd. All rights reserved.