A team of UMEI faculty affiliates and colleagues at Penn State University received word that their recent proposal to the DOE Vehicle Technologies Office has been selected for negotiation for a financial award. The proposal, titled “Tailored Bioblendstocks with Low Environmental Impact to Optimize MCCI Engines,” is a comprehensive study to link the growth and development of feedstocks for advanced biofuels from algae, through production of biocrude, upgrading to optimized fuels and combustion in diesel engines. The acronym “MCCI” refers to mixing controlled compression ignition, which encompasses conventional diesel combustion and improvements to conventional diesel combustion. At U-M, the team includes Prof. André Boehman of the Department of Mechanical Engineering, Prof. Bradley Cardinale of SEAS, and Prof. Levi Thompson of Chemical Engineering (who will be joining the University of Delaware this fall as their new Dean of the College of Engineering). At Penn State University, the team includes Prof. Daniel Haworth of Mechanical and Nuclear Engineering and Prof. Philip Savage, the Department Chair of Chemical Engineering. The project will have a 3-year duration and a budget of roughly $2.5 million, with $2 million of federal support and $500,000 of cost-share funding.
This project's scope considers how ecological engineering of communities of algae can generate novel low-GHG fuel processing routes, and the optimization of those routes to obtain optimized fuels to support mixing controlled compression ignition combustion. This team plans to pursue co-optimization studies of the fuel production process and the fuel properties and combustion behavior. The overall objective of our project is to demonstrate co-optimization of a fuel blendstock with greater than 60% greenhouse gas reduction, while improving engine thermal efficiency beyond the baseline diesel engine.
Aquatic microalgae can generate significant amounts of feedstock for the production of biocrude and tailored biofuels, and they have the potential to do so while avoiding certain limitations associated with terrestrial crop cultivation, such as land use and competition with food production. But several shortcomings of microalgal feedstocks have prevented adoption: (1) low biomass return per unit energy, (2) instability under commercial-scale field conditions, (3) inefficient use of expensive fertilizers that generate high costs and environmental impacts, and (4) lack of optimized chemical properties of the resulting fuel for combustion.
Over the past two years, we have developed a unique collaboration between ecologists, evolutionary biologists, chemical engineers, and automotive engineers at the University of Michigan who are taking a different approach to the design and optimization of algal biofuel systems (Fig. 1). Rather than trying to fight against nature to design a genetically superior strain of algae that can optimize all desired properties of a biofuel feedstock, we are using principles of ecological engineering to design a more comprehensive set of multi-species algal feedstocks that optimize several desired properties of algal biofuels at once (biocrude yield, stability, chemical quality, etc.). The first principle of ecological engineering is that no single species can be good at everything, which is true because inherent biological trade-offs impose constraints on how organisms use resources to build their biological molecules. That is why 3.6 billion years of evolution have produced species with biological differences that are complementary to one another. If we could simply find those species with the variety of desired properties, we could design tailor-made biofuels that optimize multiple properties simultaneously.
For the new work in this project, we will leverage the work performed under an ongoing NSF Emerging Frontiers in Research and Innovation (EFRI) grant and a series of internal seed grants from the University of Michigan MCubed 1.0 and 2.0 programs. THE NSF EFRI project represents a unique collaboration among engineers, ecologists, and evolutionary biologists to determine how species consortia of algae express complementary genes, metabolic pathways, and biological traits that enhance the biocrude yields, efficient recycling of nutrients, and stability of biofuel systems beyond what any single species could achieve alone.
This project will extend our work to ask how fuel compounds that can be produced from the algal biomass can be ‘bio-tailored’ based on the species composition and biological production process, as well as subsequent processing via HTL to biocrude, and upgrading of the biocrude. The proposed work will seek to optimize combustion and emissions performance, accounting first for the biological processes that dictate the biochemical composition of biocrude oil, and second for the subsequent chemical processes that comprise mixing controlled compression ignition combustion, including atomization, soot formation, in-cylinder heat transfer, and autoignition characteristics, and the dependence of these processes on the physical and chemical properties of fuels.
Together the work outlined in this proposal will provide a completed feedback loop (algae production to biocrude refining to combustion optimization to feedback to refining stage), for optimization of fuels to support MCCI combustion processes (Fig. 5 below). The engine experiments will consider fuel performance under high-efficiency MCCI engine combustion strategies and post-injection strategies for controlled engine-out soot emissions. The engine work will include an active dialogue with collaborators involved in the National Laboratory Co-Optima program.
The algal biofuel research led by U-M ecologist Bradley Cardinale has recently been in the news: