Siemens Energy has successfully completed the first firing of PetroAlgae Inc.’s biocrude fuel, a plant-based, micro-crop biomass material that is processed into a solid residue. The biocrude fuel was combined with pulverized coal in a pilot-scale burner with a thermal capacity of approximately 4 MBtu/hr.
In the pilot-scale test at the University of Utah in Salt Lake City, Utah, which was conducted in a scaled-down version of Siemens’ current pulverized coal burner design, the biocrude was blown into the fuel injector separately from the pulverized coal. Some mixing of the pulverized coal and biocrude took place within the fuel injector prior to combustion of the mixture. Up to 10% of the total heating value was provided by the biomass in these tests.
The testing showed that the biocrude was easy to handle and inject into the burner, unlike some other biomass fuels. The fuel burned well and emissions testing showed that the biomass/coal fuel mixture produced 20% lower NOx emissions than coal alone. Tests were conducted with and without external air staging. The biomass and coal mixture produced lower emissions with staging than without, as expected. Siemens intends to conduct further tests of the pilot-scale burner with increased quantities of PetroAlgae’s biocrude fuel in the near future.
PetroAlgae’s technology is designed to increase the growth and productivity of micro-crops in large-scale, open-pond bioreactors, thereby creating a biofuel of significant commercial value. The micro-crops absorb approximately twice their weight in CO2, and are harvested every few hours producing two products—a high-quality protein and a carbohydrate-rich biomass material that can be used for both co-firing in coal-fired power plants and as a drop-in replacement for petroleum-based fossil fuels.
Prior to the pilot plant-scale testing with Siemens, PetroAlgae conducted combustion testing at the University of Utah in a bench-scale burner with the biocrude providing up to 100% of the heating value. These tests were performed with and without external air staging, and they showed similar positive results in terms of handling, injection and burning. Firing the biomass fuel alone produced lower NOx emissions than the coal alone, and the NOx reduction was more pronounced under staging conditions.
PetroAlgae Inc. recently signed a Memorandum of Understanding with Asesorias e Inversiones Quilicura (AIQ), a major shareholder in Subus Chile S.A., that is expected to enable the development in Chile of a micro-crop technology system for the large-scale production of green gasoline, diesel and jet fuel.
Under the agreement, AIQ has acquired an option to purchase from PetroAlgae a standard license to build a full micro-crop technology system for commercially producing biofuels and high-value protein.