Numerical Simulation on Effects of Biomass Type on Its Fast Pyrolysis in Fluidized Bed Reactor

Bio-oil (or tar) production by the fast pyrolysis ofbiomass isone of the important technological paths for efficient utilizationand conversion of biomass. However, there are many types of biomasseswith different compositions. There is an urgent need to select thebiomass type that is more suitable for fast pyrolysis to produce bio-oil.In this work, the fast pyrolysis characteristics of three main componentsof biomass (cellulose, hemicellulose, and lignin) in a fluidized bedreactor were studied by establishing a comprehensive mathematicalmodel of multiphase flow-heat transfer-pyrolysis reaction in the fastpyrolysis process of biomass in a fluidized bed reactor using a numericalsimulation method. The fast pyrolysis characteristics of two typicalbiomasses such as hardwood and softwood with different contents ofthree main components were further analyzed. The results show thatthe yield of bio-oil or tar is 3% higher and the yield of biocharis 6% lower for the fast pyrolysis of hardwood compared to softwoodat 773 K. Simulation results demonstrated that hardwood with highhemicellulose content and low lignin content is an ideal feed forbio-oil production by fast pyrolysis.

Automated summary

In this study, the fast pyrolysis characteristics of the three main components of biomass (cellulose, hemicellulose, and lignin) were investigated using a numerical simulation method in a fluidized bed reactor. The results showed that hardwood had a 3% higher yield of bio-oil or tar and a 6% lower yield of biochar compared to softwood. Simulation results indicated that hardwood with high hemicellulose content and low lignin content was an ideal feedstock for bio-oil production by fast pyrolysis.