Gasification of Wastes in a Pilot Fluidized Bed Gasifier

Abstract

A technical assessment of gasification of various wastes in fluidized bed was made by conducting test in a 100 kWth pilot plant. The reactor was operated under simulated autothermal and adiabatic conditions, thus allowing scaling-up the results to industrial units. Four feed stocks were tested: orujillo, meat and bone meal, dried sewage sludge and compost from municipal solid waste. The tests were made for each fuel by changing the air ratio (stoichiometric ratio), allowing characterization of the process in terms of gas composition, gas heating value, gasification efficiency, carbon conversion and tar content. Comparison of the results with those obtained with commercial wood pellets was made. The results show that orujillo and dried sewage sludge are a potentially fuel to be gasified if carbon conversion is increased. On the other hand, gasification of meat and bone meal was found to be a process with low efficiency, despite the fuel is fully converted in the bed. Municipal solid waste is a fuel difficult to gasify because the gasification process has low efficiency and generates a great amount of ash difficult to dispose. In order to increase carbon conversion in the reactor, co-gasification of orujillo or sewage sludge with meat and bone meal is considered a promising option.