Liquid Bio-Fuel Production From Non-Food Biomass via High Temperature Steam Electrolysis

Abstract

Two hybrid energy processes that enable production of synthetic liquid fuels that are compatible with the existing conventional liquid transportation fuels infrastructure are presented. Using biomass as a renewable carbon source, and supplemental hydrogen from high-temperature steam electrolysis (HTSE), these two hybrid energy processes have the potential to provide a significant alternative petroleum source that could reduce US dependence on imported oil. The first process discusses a hydropyrolysis unit with hydrogen addition from HTSE. The second process discusses a process named Bio-Syntrolysis. The Bio-Syntrolysis process combines hydrogen from HTSE with CO from an oxygen-blown biomass gasifier that yields syngas to be used as a feedstock for synthesis of liquid transportation fuels via a Fischer-Tropsch process. Conversion of syngas to liquid hydrocarbon fuels, using a biomass-based carbon source, expands the application of renewable energy beyond the grid to include transportation fuels. It can also contribute to grid stability associated with non-dispatchable power generation. The use of supplemental hydrogen from HTSE enables greater than 90% utilization of the biomass carbon content which is about 2.5 times higher than carbon utilization associated with traditional cellulosic ethanol production. If the electrical power source needed for HTSE is based on nuclear or renewable energy, the process is carbon neutral. INL has demonstrated improved biomass processing prior to gasification. Recyclable biomass in the form of crop residue or energy crops would serve as the feedstock for this process. A process model of syngas production using high temperature electrolysis and biomass gasification is presented. Process heat from the biomass gasifier is used to heat steam for the hydrogen production via the high temperature steam electrolysis process. Oxygen produced form the electrolysis process is used to control the oxidation rate in the oxygenblown biomass gasifier.

Review of the Potential of Nuclear Hydrogen for Addressing Energy Security and Climate Change

“…Beyond providing hydrogen for upgrading petroleum resources, HTE can also be used to support the production of synthetic fuels from non-conventional carbon sources such as biomass [23] or coal [37], or directly from carbon dioxide via co-electrolysis [18]. The benefits of carbonfree supplemental hydrogen for biomass-and coal-toliquids are significant.…”

“…For example, distributed production of synthetic liquid fuels based on biomass and supplemental hydrogen offers a method of producing carbon-neutral liquid fuels such as biodiesel and ethanol [23]. The concept for this hybrid energy system is provided in Fig.…”

“…Supplemental hydrogen from electrolysis enables achievement of high carbon utilization such that about 95% of the carbon in the biomass feedstock is retained in the syngas product, as shown in Fig. 7 [23]. Oxygen produced from the electrolysis process is used to control the oxidation rate in the oxygen-blown biomass gasifier.…”

“…As an alternative to centralized large-scale systems with direct coupling to high-temperature reactors, distributed hydrogen production could be accomplished using modular HTE units powered from grid electricity and an alternate high-temperature heat source such as concentrated solar energy [22] or a biomass gasifier [23]. This approach could be quite economical if off-peak electricity is used [24].…”

Large Scale Hydrogen Production From Nuclear Energy Using High Temperature Electrolysis

“…As an alternative to centralized large-scale systems with direct coupling to high-temperature reactors, distributed hydrogen production could be accomplished using modular HTE units powered from grid electricity and an alternate hightemperature heat source such as concentrated solar energy [25] or a biomass gasifier [26]. This approach could be quite economical if off-peak electricity is used [27].…”