A Pilot-Scale, High-Pressure, Biomass Slurry Pump

Aerodyne Research Inc. (ARI) and Worcester Polytechnic Institute (WPI) propose to design a high- pressure slurry pump for the delivery of biomass solids into a high-pressure hydrothermal reactor for biofuel production. Biomass conversion techniques involving a hydrothermal phase have many advantages over other biomass conversion methods: they do not require the costly sugar release pre- treatment step required for fermentation or the water removal and drying pre-treatment steps required for pyrolysis; they achieve much more rapid rates compared to biochemical techniques; they yield a higher quality bio-oil than is produced via biomass pyrolsis. However, existing hydrothermal processes have been tested either using model feeds or using real feeds batch mode. The lack of continuous flow data with real feeds significantly impedes the commercialization of hydrothermal conversion technologies. One of the major challenges to construct a continuous hydrothermal biomass conversion process is the lack of commercial pumps that can deliver concentrated biomass slurry flows to a high-pressure reactor at appropriate (low to mid) flow rates. The lack of a commercial pump provides a niche that the proposal team can address. In this proposed effort, we will design and construct a prototype high-pressure slurry pump for the delivery biomass solids in high-pressure hydrothermal processes. In Phase I, we will focus on proof-of- concept studies to identify key design parameters. We will perform laboratory experiments to evaluate the effects of continuous slurry feeds on conversion performance in a hydrothermal reactor. We will also design a valve system to allow for delivery of slurry particles using state-of-the-art computational fluid dynamics simulations and experimental evaluation. Finally, a feed system that can prevent particle sedimentation in the feed will be designed. At the end of Phase I, key design parameters and their relevant operation ranges will be identified and quantified. This will facilitate our work in Phase II to package a prototype pump that can be coupled with any continuous hydrothermal reactor systems for biomass conversion to fuels or high value bio-based products.