COMBUSTION STUDIES OF FLUFF REFUSED-DERIVED FUEL (RDF) IN FLUIDIZED BED (FB) SYSTEM

Among most conventional incineration systems, the fluidized bed combustor (FBC) had been described as one of the most advantageous by providing simple operation with ability to accommodate low quality fuel as biomass, sludge and MSW with high moisture; reduced auxiliary fuel use; reduced operating and maintenance costs. This could only be achieved if optimal operating parameters are determined. This paper presents the methods and part of the findings of an on-going research aimed at optimizing the operating parameters that gives lowest emissions in the combustion of a fluff refused-derived fuel (f-RDF) in pilot scale fluidized bed combustor. The method adopt includes – cold fluidization studies in rectangular model column to determine the fluidizing velocity of the inert bed material (silica sand), and the effects of increasing fluidizing numbers on the mixing behavior of bed and fuel. This is closely followed by combustion study in the pilot scale FBC. Experimental findings from the cold fluidization studies indicates that a sand with particle size range (300 – 600 μm) gave a fluidizing velocity of 0.1 m/s at bed height 1W of column. Similarly, fluidizing numbers of 4Umf and above gave better mixing of inert bed material with fuel. Although, the combustion study is at its preliminary stage, the results from the cold fluidization shows that the fluidization is better at bubbling fluidization regime against circulating fluidization regime which requires much higher fluidizing velocities and higher turbulence.