The United States is developing biomass-based oil production processes for efficient carbon conversion

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On January 10, 2009, researchers at the United States’ Edward ** Laboratory (INL) announced that they were developing a biomass-to-liquid (BTL) process for efficient carbon conversion called Bio-Syntrolysis. This process combines high-temperature steam electrolysis (HTSE) with biomass gasification; the syngas produced is then used to further convert into synthetic fuels and chemicals. This process can efficiently convert biomass carbon into syngas (>90%). Using the given typical Fischer-Tropsch synthesis process thereafter, the Bio-Syntrolysis process can convert approximately 90% of the carbon in biomass into liquid synthetic fuel. In comparison, conventional biomass or coal gasification for liquid fuel production can convert only 35% of the carbon into liquid fuel. Similarly, conventional biological ethanol production routes can only convert ~35% of biomass carbon into liquid fuel. In the Bio-Syntrolysis process, the heat generated from biomass gasification is used to produce steam, which enhances the hydrogen production efficiency of the High-Temperature Steam Electrolysis (HTSE) process, while the biomass itself serves as a source of carbon. The hydrogen from HTSE can be used, and the biomass carbon used to produce syngas has a high utilization rate, while the oxygen obtained from water explosion is used to control the gasification process. This new process is an innovation by Edward **Laboratory (INL) in the field of Syntrolysis technology. The Syntrolysis technology utilizes high-temperature electrolysis through solid oxide electrolyte cells; its advantage is that the electricity required can come from nuclear energy or renewable sources, and at the same time, the heat generated in industrial processes can be used to convert water and carbon dioxide into syngas. However, a very high energy density is required to burst pure CO2. Researchers found that using the Bio-Syntrolysis process, the amount of syngas produced per unit of electricity is much higher compared to the Syntrolysis process (~20%). In the Bio-Syntrolysis process, only a small amount of CO2 is produced in the biomass gasifier, with most of it being CO. The heat generated by CO production is just sufficient to meet the heat required to heat water into steam, for use in High-Temperature Steam Electrolysis (HTSE). In the simulation studies, a research team from Edward** Laboratory (INL) concluded that the carbon utilization rate in the Bio-Syntrolysis process is only slightly affected by the temperature of the gasifier; it depends on both the feedstock and the gasifier temperature, with a carbon utilization rate ranging from 94% to 95%. The syngas production efficiency is close to the power cycle efficiency. It is assumed that the thermal efficiency of the power generation cycle is 50% (the efficiency of GEN IV nuclear reactors), while the production efficiency of syngas ranges from 70% to 73%. The electricity required can come from non-fossil resources such as nuclear energy, hydroelectric power, wind energy, or solar energy, in order to keep this process carbon-neutral. 1. High-temperature electrolysis: INL researchers achieved a milestone in September 2008 by producing hydrogen on a large scale through high-temperature electrolysis, moving from smaller-scale production to large-scale operations and generating 5.6 cubic meters of hydrogen per hour. High-temperature electrolysis (HTE) can separate water into hydrogen and oxygen by utilizing some energy; the heat required comes from high-temperature steam, replacing electricity. Compared to using heat directly, THE reduces the total energy required because the efficiency of converting heat into electricity is lower. An electrolytic cell consists of a solid oxide electrolyte and conductive electrodes placed at both ends of the electrolyte. A high-temperature mixture of steam and hydrogen is fed to the anode of the electrolyte. 2. Bio-Syntrolysis: A plant with a capacity of 25,000 barrels per day (i.e., 1.05 million gallons or 3.974 million liters) for converting all biomass into liquid fuel requires an investment of around $2 billion. The production cost of this device is $2.80 per gallon, with 1000 MW of electricity being used. For this process to be widely adopted, non-fossil energy sources must be used. INL began conducting simulations and economic analyses of the Bio-Syntrolysis process in May 2008, and filed a U.S. patent application. (Greencarcongress, 2009-1-10)