Bioengineering Resources, Inc. (BRI) has been developing a synthesis gas fermentation process whereby biomass can be converted to synthesis gas (consisting primarily of carbon monoxide, carbon dioxide, and hydrogen) via a high temperature gasification process. Anaerobic bacteria are then used to convert the synthesis gas into ethanol. The BRI process can be used to produce ethanol from cellulosic wastes with high yields and rates. This is made possible because BRI has developed bioreactor systems for fermentation that results in retention times of only a few minutes at atmospheric pressure and less than a minute at elevated pressure. These retention times result in very economical equipment costs.
New developments from a previous post on this process have been:
- Awarding a new $2.4 million contract, the Corn Stover Project, by DOE
- Completion of process design and costing of a standard plant
- Completion of a Technical Evaluation report by Parsons
- Completion of an Emissions Testing Report that is needed for permitting and construction of their first plant.
- At least one plant is expected to begin commercial operations before the end of 2006.
Their process is depicted in the following flow diagram and has been discussed in the previous post.
Under a $2.4 million grant from the U.S. Department of Energy, Bioengineering Resources, Inc. (BRI) is investigating the feasibility of locating BRI facilities that produce ethanol by processing corn stover next to conventional grain alcohol plants. The study is assessing the synergies involved with such co-location, such as the utilization of waste heat and power from a BRI plant to reduce the operating costs of the neighboring sugar fermentation plant. Chippewa Valley Ethanol, a Minnesota corn producers cooperative, and the engineering firms of Katzen International and Burns & McDonnell are participants in the project.
In December, 2004, Parsons Corporation and Katzen completed the process design, equipment list and capital cost projections for a standard BRI plant module that could be installed throughout the world.
In October, 2005, Parsons Corporation delivered its final BRI Technology Evaluation Report, an independent review and validation of the technology’s commercial potential for the production of ethanol from biomass and carbonaceous wastes. In early November, Parsons further completed the necessary Emissions Testing Report that will lead to the permitting and construction of BRI’s first commercial plants.
The company is continuing the testing of various feedstocks, which will lead to the engineering design and construction of BRI’s first commercial plants. These tests involve such feedstocks as wood waste, auto shredding residue and municipal solid waste. According to Parsons’ Technology Evaluation report, “The ability of BRI to process this material and generate waste streams that are within regulatory limits or easily treatable to regulatory limits can be viewed as an important technological step forward.”
Katzen has prepared this background information on the potential of the process:
It is estimated that in the U.S., farms produce 120 million tons of unused corn stover annually, which could supply two quads of energy. Recent research has led to the successful development of various gasifier designs to convert agricultural residues into useful energy. Some of these units have been commercialized, but few have been economically successful, primarily because the product of gasification, heat, has a low value.
This Corn Stover Project will investigate the production of higher value liquid fuel, ethanol, and by-product power from corn stover. The stover is gasified and the CO, H2 and C02 in the synthesis gas is fermented into ethanol. A single fermentation product, ethanol, is produced and high theoretical yields (140 gallons per ton) are possible since all biomass components, except the ash, are utilized. The purpose of this project is to develop and demonstrate at pilot scale an optimal gasification / fermentation process to utilize corn stover.
A major emphasis will be placed on the integration of a stover ethanol facility with a conventional grain alcohol plant in the Corn Belt. The corn plant can utilize waste heat from the stover plant. Other synergies include the use of common ethanol storage and load out facilities, utilities, waste treatment, maintenance shops, laboratories, roads, fire protection, offices, etc. The economy of these commonalities will be quantified to define an optimal corn / stover plant that can serve as a model for the industry.
Utilization of the available U.S. corn stover would produce about 1-0 billion gallons of ethanol per year, reducing oil imports by five percent and improving our balance of payments by $350 million per year. Additionally, 4000 MW of power would be produced, reducing natural gas imports by 85 billion CF per year. The full exploitation of this technology would create 40,000 direct high-level jobs in rural farm areas and contribute about $10 billion annually to local economies.
Perhaps the greatest benefit to the economy is the added income to the farmer from sale of corn stover. Based upon $30 per dry ton, the additional income to the farmer would be $60 per acre, increasing farm income by $3.5 billion annually. Beyond these economic benefits are the improvements to the environment through the use of renewable and clean burning fuel
This technology can lead the nation to energy independence through the use of its agriculture and other residues.
Thanks to the Bioconversion Blog for reminding me of this technology, which inspired me to check the progress that BRI was making.