High quality syngas production via steam-oxygen blown bubbling fluidised bed gasifier. (15th May 2016)

• Record Type: Journal Article
• Authors: Stendardo, Stefano; Foscolo, Pier Ugo; Nobili, Mirko; Scaccia, Silvera
• Is Part Of: Energy. Volume 103(2016)
• Page Start: 697
• Page End: 708
• Publication Date: 2016-05-15
• Subjects: Research infrastructure -- High quality syngas -- Coal gasification -- Kinetic and equilibrium modelling; Power resources -- Periodicals; Power (Mechanics) -- Periodicals; Energy consumption -- Periodicals; 333.7905
• DOI: 10.1016/j.energy.2016.03.011
• Languages: English
• ISSNs: 0360-5442

Abstract

Abstract: This paper presents experimental and modelling results of fuel gas obtained in a steam-oxygen blown fluidised bed pilot scale (500 kWth ) coal gasifier that is part of the ZECOMIX (Zero Emission of CarbOn with MIXed Technologies) research infrastructure run by ENEA. As there is poor information about start up and steady state operation of fluidised bed gasifiers at such a scale, in this work we investigated the influence of some important parameters such as coal ignition temperature, feeding rate of particulate bed material (olivine sand) and transition from oxidant to reducing environment. The experimental runs confirmed the crucial importance of S/O (steam/oxygen) ratio on the product gas composition. High quality syngas (low content of methane, below 1.0 v/v %, and high content of H2 and CO: CO + H2 61.0 v/v%) was obtained with S/O = 1.1. A shortcut model of the gasifier was also formulated, considering instantaneous coal pyrolysis, kinetics of coke steam reforming reactions in the fluidised bed, and achievement of thermodynamic equilibrium for the water gas shift reaction. The model takes into consideration the average residence time of coke particles into the gasifier: since this is a characteristic parameter of the reactor, the performance of different fluidised bed gasifiers can be simulated. Graphical abstract: Highlights: Key parameters have been experimentally evaluated during anthracite gasification. High quality synthetic fuel gas has been yielded with a low content of methane. The product syngas is suitable for H2 production. Kinetic and equilibrium expressions have been used to model coal gasifier.