Sustainable fuel for the transportation sector

Abstract

A hybrid hydrogen-carbon (H2CAR) process for the production of liquid hydrocarbon fuels is proposed wherein biomass is the carbon source and hydrogen is supplied from carbon-free energy. To implement this concept, a process has been designed to co-feed a biomass gasifier with H 2 and CO2 recycled from the H2-CO to liquid conversion reactor. Modeling of this biomass to liquids process has identified several major advantages of the H 2CAR process. (i) The land area needed to grow the biomass is <40% of that needed by other routes that solely use biomass to support the entire transportation sector. (ii) Whereas the literature estimates known processes to be able to produce Ϸ30% of the United States transportation fuel from the annual biomass of 1.366 billion tons, the H 2CAR process shows the potential to supply the entire United States transportation sector from that quantity of biomass. (iii) The synthesized liquid provides H 2 storage in an open loop system. (iv) Reduction to practice of the H 2CAR route has the potential to provide the transportation sector for the foreseeable future, using the existing infrastructure. The rationale of using H 2 in the H2CAR process is explained by the significantly higher annualized average solar energy conversion efficiency for hydrogen generation versus that for biomass growth. For coal to liquids, the advantage of H 2CAR is that there is no additional CO2 release to the atmosphere due to the replacement of petroleum with coal, thus eliminating the need to sequester CO 2. biofuels ͉ coal ͉ hydrogen ͉ oil

Improvement of biomass through lignin modification

“…As the lignin polymer is more reduced than polysaccharides, biomass with a higher lignin content would be a better raw material for gasification and Fischer-Tropsch-type processes such as those that have been used to convert coal to liquid fuel (Agrawal et al, 2007;Schubert, 2006).…”

Research core and framework of sustainability science

“…Hydrogen gas can be produced from cellulose fermentation by adding a small voltage to bacteria, but a slow production rate and low-energy efficiency of around 60% hampers its application. Agrawal et al (2007) proposed a mixture of biomass and hydrogen for a liquid biofuel feed. By combining biomass with hydrogen, the land area needed to grow the biomass is reduced to less than 40% of that needed by other routes that solely use biomass.…”

The Challenge of Bioenergies: An Overview

“…Alternatively, hydrogen can be produced from another fuel (e.g., ethanol, biodiesel, gasoline, or synfuel) via onboard reformers (hydrogen fuel processors). This is probably the best solution because synfuel can be produced from local feedstocks through the Fischer-Tropsch process, transported and distributed through existing technologies and infrastructures (Agrawal et al, 2007;Takeshita & Yamaji, 2008). This consideration also applies to biofuels.…”

“…As a consequence, the US alone has reached a level of oil consumption in the transportation sector that approaches 14 Mbl/day and corresponds to a release of 0.53 gigatons of carbon per year (Gt C/yr). The current global release of carbon from all fossil fuel usage is estimated to be at 7 Gt C/yr and is expected to rise to ~14 Gt C/yr by 2050 (Agrawal et al, 2007). It has been estimated that global energy consumption could reach 30-60 TW by 2050.…”