The proposed work will develop the science and technology needed to design an energy-efficient, compact, autonomous, and inexpensive biomass reactor for remote locations that will thermo-chemically process chipper-size particles (10?15 mm) into liquid bio-oil. It removes the impediments of drying and particle size reduction [~2 mm in size] by developing technology that will use chipper-size air-dried particles. It enables an economically attractive high biomass processing rates that are not possible with the current technology in a small-scale reactor. It also upgrades the bio-oil on-the-fly by de-oxygenating it such that it may become a feedstock in conventional petroleum refineries. Finally, the proposed distributed reactor technology is important for soil sustainability because the minerals and ash generated by the reactor are distributed back into the field (or forest) for sustainable future growth. Removal of excess biomass from the forests also prevents forest fires and promotes healthy forest growth.
The proposed ideas are drastically different from the currently dominant approaches in the field. Therefore, the proposed work will provide data and develop models to provide a convincing proof-of- concept. Due to the early exploratory stage of this project, it is high-risk but it has a high-payoff potential.
This research will provide invaluable data that will lead to an improved understanding of pyrolysis of various shape chipper-size biomass particles and their ensembles through extensive measurements of temperature, evolved chemical species, and mass loss rate at various heating rates. It will also develop a unified predictive mathematical model with decomposition kinetics and internal pressure generation for various shape particles by using oblate and prolate coordinate systems. The model will also provide a basis for correlating the data that will be used in reactor design. Two methods are proposed for de-oxygenating (upgrading) the bio-oil. These are: (i) slow preheating (torrefaction) prior to fast pyrolysis and (ii) use of a catalyst filter prior to pyrolyzate condensation. Simultaneous measurements of the chemistry during bio-oil production by GC and LC will quantify the effectiveness of the two proposed techniques for getting rid of oxygenates from bio-oil.
This research addresses a national priority area of converting the nation?s sustainably available biomass resources into liquid fuels. If successful, it will offer a novel method of producing carbon-neutral transportation fuels while creating numerous new well-paying jobs. Further, this research will help restore the forest health by removing hazardous fuel and reduce the danger of forest fires. The United States spends hundreds of millions of dollars per year to combat wildland fires that cause billions of dollars worth of damage to private and public property. This research will also have a great educational impact because energy and sustainability are very popular subjects among undergraduate and graduate students at the University of Michigan. While only one graduate student will be directly supported by the project, we will provide research experience to undergraduate students by giving them the opportunity to work with the graduate student and the PI.
