(529h) Transportable Fast-Pyrolysis Process for Distributed Conversion of Waste Biomass to Renewable Liquid Fuels

In Florida alone, sugarcane bagasse, orange residue from juicing, and logging/mill residues are produced at a rate exceeding 16,000 dry tons per day. However, these agricultural residues are often spread over large areas and are difficult to access, particularly the logging residues. Rather than trucking large quantities of low-density biomass to a massive centralized biofuel production plant, the distributed conversion of agricultural residues into bio-oil is an attractive alternative for sustainable biofuel production. Opportunities also exist for the conversion of mixed waste to biofuel at forward-deployed military outposts, where the true delivered cost of fuel often exceeds $15 per gallon. Mainstream Engineering (MEC) recently commissioned a highly instrumented fast-pyrolysis pilot plant (1 ton/day) to demonstrate small-scale conversion of waste organic material to bio-oil. The pilot reactor was designed for flexibility and tight process control, as we explore the product yield and quality for a variety of feedstocks. Testing to date has used pine sawdust or a granulated mixed waste surrogate consisting of corrugated cardboard, office paper, and several plastics.

MEC is working to commercialize the portable process at a 10 ton/day scale for commercial applications and at the <1 ton/day scale for military applications. Our efforts have focused on improving the reactor yield by minimizing secondary cracking and improving the energetics with tight heat integration. Both improvements are geared towards achieving viable process economics at a small thoughput. We have also experimentally investigated the pre-processing (size reduction and drying) and end-use utilization of raw bio-oil in a burner/boiler. Results will be presented on our pilot reactor testing, techno-economic analysis of the portable reactor approach, and initial results from our efforts to mildly upgrade raw bio-oil to a renewable residual-grade fuel oil.