FAST PYROLYSIS OF BIOMASS
2011 Annual Report
1a.Objectives (from AD-416)
To develop an energy self-sufficient pyrolysis equipment for the production of renewable biocrude. A two-zone fluidized-bed reactor capable of generating hot material in one zone to drive the endothermic pyrolysis reaction in a separate zone is the primary objective. In this way, two streams are generated: a conventional hot combustion gas stream where thermal energy can be recovered by conventional means, and a pyrolysis product stream where liquid products are separated from high calorific value gaseous products.
1b.Approach (from AD-416)
An existing South African patent originally designed for gasification and having the dual-zone feature will be used as the prototype to develop a pyrolysis reactor. The design approach will include scale-up and/or scale-down of the fluidized bed prototype by bed area reengineering. A necessary approach is to build development units at full height to test the technology. It is proposed that the design is thoroughly thought through before investing in any commercial scale demonstrations. It is UP’s intension to ensure that the practical experience of researchers in this field is properly incorporated in the design and seeks the collaboration of such expertise at ARS which has a biomass pyrolysis program with similar objectives. The strategic approach is to involve Dr. Boateng of ARS who has demonstrated experience in the design of similar systems.
Completed design of a twin fluidized bed reactor named Combustion Reduction Integrated Pyrolysis System (CRIPS) capable of burning residual char in the combustor to heat a sand medium and the heated sand transferred by an auger to the pyrolyzer to provide heat for biomass pyrolysis. Patent is pending. A 10 kg biomass system of the design has been constructed and being assembled at the University of Pretoria for testing. To ensure design operability a cold-flow model of the design has been constructed in Plexiglas and operated at ERRC to provide hydrodynamic information of the inner workings of the system. Progress was monitored by e-mails and collaborator's visit.