Algae Biomass Promises to Impact Energy Markets
The immediate promise of algal fuels and energy derives from the prolific growth of algal biomass, and the relative economy and simplicity of using algal biomass compared to algal bio-oils. While other companies are focusing on the long-term (10 year) goal of economical algal biodiesel, PetroAlgae is taking the quick and sure route of exploiting algal biomass.
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. _GCC
A startup in New Mexico, meanwhile, is taking to long-term approach of making biodiesel directly from algal bio-oil.
Officials cut the ribbon today on the world's first biorefinery designed specifically to extract biofuel from micro algae. The facility was constructed at the site of the CEHMM algae production ponds near Artesia.The CEHMM product cannot compete directly with petro-diesel, so it must be sold as a fuel additive. The biomass co-products of algal production may also be sold as livestock feed.
CEHMM teamed up with Solution Recovery Systems to develop the system, which can separate the crude bio diesel fuel from the bio-mass byproduct, which is rich in nutrients and is being considered as a supplement in livestock feed, he said.
Lynn said the ponds and facility were constructed on land not being used for agriculture and the process uses water that is too salty to be used for drinking or irrigation. Processes are being explored to purify wastewater from the oilfields to be used in the algae process, he said.
The fuel produced is more lubricating to engine parts than standard petroleum and cleans engine systems. The fuel is also lower in emissions, he said.
In fact, the salt water micro-algae organisms in the CEHMM ponds actually consume carbon dioxide, Greg Brown, business manager for CEHMM said. A Sandia National Laboratory Study revealed a 700,000 gallon micro-algae pond can sequester one metric ton of carbon per day, he said.
The green fluid produced in the pond is reduced to slurry from which the oil and the biomass are separated, Lynn said. 90 percent of the mass of the crude oil can be converted to fuel. The remaining bio-mass could conceivably be fed to livestock because it contains up to 60 percent protein, he said.
The sunny weather, open spaces and brackish ground water make southeast New Mexico and parts of Texas ideal for Algae production, Lynn said. _cehmm_via_biofuelsdigest