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"The increased need to reduce carbon dioxide emissions to prevent global warming have led to an interest in biomass and solid waste as fuel sources. As a potential renewable energy resource, biomass and solid waste materials are receiving more attention worldwide. A number of techniques and methods have been proposed for reducing gaseous emissions from a fossil fuel conversion thermal system. This paper presents a pilot-scale bubbling fluidized bed gasifier with a diameter of 0.68 m and a height of 1.50 m using an oil burner to heat the bed. This study used four types of biomass materials mixed with coal at different mass composition ratios in an air gasifying agent. The gasification tests were conducted under steady-state at an operating condition that is typical for gasification. The influence that the solid waste and coal ratio had on gasification efficiency was investigated. The gasification efficiency and the carbon conversion efficiency increased when the mass ratio of the solid waste fuels increased."

"A three-dimensional Eulerian Multi-Fluid Model (MFM) of biomass gasification in full-loop Circulating Fluidized Beds (CFBs) has been developed. The conservation equations of mass, momentum, and energy are solved by well-known Navier-Stokes formulation types. The Kinetic Theory of Granular Flow (KTGF), common chemical reactions in biomass gasification, and standard k-ε turbulence model are considered. These equations are used to describe the spatial velocity, temperature, and concentration for each phase and species. The inter-solid phase heat-transfer mechanisms, which consist of direct solid-solid conduction and solid-solid conduction through fluid medium, are also considered. The results are compared to existing experimental data. It is demonstrated that the model which considers all inter-solid phase heattransfer mechanisms provides better predictions in terms of synthetic gas (syngas) compositions than the model considering direct solid-solid conduction through contact area only and the model without solid-solid heat-transfer mechanisms. From this, hydrodynamics and heat and mass transfer inside this complex system are analyzed. The results can be useful for better design and optimization of biomass gasification in CFBs."