Biomass furnace for externally fired gas turbine: Development and validation of the numerical model

Abstract

Externally-fired gas turbines (EFGT) are currently being investigated for co-generation from biomass, because of their ability to deal with low-grade fuels without the complexity of gasification. Main drawbacks of the technology are related to the high thermal stresses experienced by the heat exchanger. The present work proposes a computational fluid dynamics (CFD) analysis of a grate-fired furnace installed in a EFGT cycle, with the purpose to provide a tool for detecting the most critical regions in the furnace. The model is complemented with a process simulation of the entire EFGT cycle. Different approaches for treating the fuel bed and their impact on the CFD analysis are discussed and validated through the availability of in-flame measurements of temperature and chemical species. Predictions indicate the need for a detailed fluid dynamic characterization of the grate region, which was found to largely impact the furnace flow and thermo-chemical fields

Potential use of wood pyrolysis coproducts: A review

“…Differently from internal combustion engines and the direct-fired gas turbines, which requires high quality fuels, the externally fired micro gas turbine can deal with biomass and other low quality fuels (synthetic gas, heavy oil, coal and garbage). 80,81 External combustion technologies also allow the use of solid biomass as complementary fuel, increasing the profitability of the small biomass plant and the competitiveness with other solutions in the market. Moreover, external combustion technologies integrate the advantages of gas turbines (low operational costs, high lifetime and reliability, relatively high energy efficiency even at small size) and the capability of using low quality biofuels.…”

“…Moreover, external combustion technologies integrate the advantages of gas turbines (low operational costs, high lifetime and reliability, relatively high energy efficiency even at small size) and the capability of using low quality biofuels. 81 Mikielewicz et al 82…”

Investigation of a Biomass-Driven Cogeneration System Integrated with an Externally Fired Gas Turbine, Organic Rankine Cycle, and Absorption Refrigeration Cycle: Thermodynamic and Exergoeconomic Analyses and Optimization

“…In the EFGT cycle, the combustion process takes place outside the cycle and the high-temperature combustion products transfer heat to the working media through a high-temperature heat exchanger (HTHE) [16,17]. The EFGT cycle lowers the strict fuel quality requirements without the need for the gas cleaning process and complex fuel compression and injection equipment, which improves the system's economy and reliability [18,19]. However, one of the main shortcomings of the biomass gasification-based EFGT cycle is the relatively low energy efficiency; thus, additional waste heat recovery systems should be employed to enhance the performance of such systems [20].…”

CFD multiphase combustion modelling of oleic by-products pellets in a counter-current fixed bed combustor

“…Details on the Modelling of biomass combustion as well as on the solid phase and on the gas phase reactions are reported in the literature [5][6][7][8][9][10][11][12][13][14]. Typically, a configuration consisting of two coupled zones (the bed and the free-board) is considered [15][16][17] in which the two zones are separated by an interface allowing mass and energy exchanges [2,6,[17][18][19][20]. Two general types of models are incorporated that are associated with the homogeneous and heterogeneous phases of the process [5,18,21].…”