This work is heartening because it promises a viable gasification process. They have tricked out the catalyst needed to get the job done without actually burning fuel in a kiln environment or applying extraordinarily high pressures. This is a vat process that converts the input to methane mostly and CO2.
They emphasize algae which is likely an extreme but easy to use feedstock. It also appears able to handle other organic material. I suspect that they can handle all organic material in this pressure cooker.
The temperature is half that of the depolymerization method and the pressure will be much lower. We transition to more conventional processing equipment that is likely on the shelf. That will make the roll out of the technology a lot less tentative.
This outfit is focused on algae, but a continuous processor may be possible with this technology. If it can be used to handle all animal waste then it will be valuable to the farm industry where there is already a market for the natural gas and they are too large to be able to use natural decomposition.
Release date: May 6, 2009
Staci West, PNNL, (509) 372-6313
Jim Oyler, Genifuel Corporation, (801) 467-9976
Low-cost process produces natural gas from algae
DOE lab licenses high-yield gasification technology
RICHLAND, Wash. – A new method for converting algae into renewable natural gas for use in pipelines and power generation has been transferred from the Department of Energy's Pacific Northwest National Laboratory to the marketplace under a license between Genifuel Corporation and Battelle.
The method, called catalytic hydrothermal gasification, creates natural gas out of algae - more quickly, more efficiently and at higher yields than other biofuel processes. Genifuel expects the process also requires less capital investment. The license agreement moves this technology for renewable energy production a step closer to commercial reality. Battelle operates PNNL for DOE.
"Algae and other aquatic biomass hold significant promise for our country's ability to produce renewable energy domestically," said Genifuel President Jim Oyler. "At Genifuel we have developed efficient growth and harvesting techniques for the aquatic biomass. With this gasification process, we can convert the biomass to a clean fuel that is almost completely carbon-neutral."
He calls the PNNL process an "elegant system," noting that more than 99 percent of the biomass is gasified to produce renewable natural gas and byproducts such as carbon dioxide which can be recycled and reused in the algae growth ponds.
PNNL originally developed the catalytic gasification process to clean up industrial and food processing waste as an alternative to incineration. Over the past 10 years, PNNL scientists advanced the technology to include a more stable catalyst that enables it to also convert wet biomass, such as algae. PNNL has tested the gasifier with terrestrial plants, kelp and water hyacinths. It works especially well for aquatic biomass such as algae, because the feedstock doesn't require drying before fuel production.
Battelle granted Genifuel an exclusive license for the technology. As a national laboratory, one of PNNL's missions is to advance science and technology toward solutions that industry can take to the marketplace.
"Electricity produced from this natural gas can help electric utilities meet Renewable Portfolio Standards that require renewable energy sources," Oyler said. "Existing natural gas pipelines can deliver the fuel, or it can be used to produce electricity onsite in conventional natural-gas turbine generators."
The PNNL gasifier runs at relatively low temperatures - 350-degrees Celsius compared with 700-degrees or more for other systems - in a small stainless steel reactor.
According to Doug Elliott, the PNNL scientist who invented the gasification process, "It is simple - we put wet biomass like algae in the gasifier, where it is catalytically converted, and we collect fuel gas and byproducts.
"It's serendipity that our system creates carbon dioxide as a byproduct that Genifuel needs naturally to grow the algae," he said. "It's a completely green process."
Compared with other methods of gasifying biomass, such as anaerobic digestion, PNNL's process works 400 times faster and gives higher yields.
While simple in concept, the science behind the gasification process is actually quite complex. The technology has been under development for a number of years. PNNL scientists have achieved significant advances in the chemistry of catalysts and the selection of the optimum temperatures and pressures for the process, as well as improving the systems to protect the catalyst from impurities in the biomass.
PNNL scientists have extensive expertise in catalysis and reaction engineering, with particular focus on solutions for efficient use of bioproducts, converting biomass and renewable feedstocks to fuels and chemicals, and reducing environmental emissions.
Genifuel grows aquatic biomass, such as algae, in shallow ponds or troughs, then harvests and processes the biomass for conversion using the PNNL technology. Water used in the growth ponds doesn't have to be high-quality fresh water, and can be treated wastewater, brackish or alkaline water, or even salt water, Oyler said. Non-crop land can be used, so the process doesn't compete with food production.
Genifuel Corporation was formed in 2006 to advance commercial production of renewable energy. The company has developed efficient means to grow and harvest aquatic biomass and has been working with PNNL for nearly two years to demonstrate low-cost production of renewable natural gas from this feedstock. In addition to the license from Battelle, Genifuel also has a number of patents pending for its growth and production technologies using aquatic biomass.
Pacific Northwest National Laboratory is a Department of Energy Office of Science national laboratory where interdisciplinary teams advance science and technology and deliver solutions to America's most intractable problems in energy, national security and the environment. PNNL employs 4,250 staff, has a $918 million annual budget, and has been managed by Ohio-based Battelle since the lab's inception in 1965.