(694e) Process Integration and Optimization of Hydrogen Production Strategies

Yuan, W. - Presenter, Auburn University
Bommareddy, S. - Presenter, Auburn University

Experimental researchers in the Consortium for Fossil Fuel Science (CFFS) are developing novel technologies for hydrogen production and storage, however the economic and environmental viability of the technologies are mostly evaluated separately rather than in an integrated manner. In this work, we aim to address this gap through the development of integrated system engineering strategies for modeling, integration and optimization of hydrogen polygeneration plants.

We are developing process models for a variety of hydrogen production schemes. Using process integration techniques and advanced computer-aided tools, the systems have been optimized and the economic potential as well as the environmental impact of the technologies evaluated. Several reforming techniques including four developed within CFFS have been studied based on small and large scale production of hydrogen. Literature data along with data obtained in other research projects at Auburn University has been used to develop models for partial oxidation (POX), steam (SR) and autothermal reforming (ATR) of a variety of hydrocarbon resources. In addition, data provided by other researchers in CFFS has been used to build similar models for super critical water reforming (SCWR) of methanol and biomass (using glucose as a model molecule), dry reforming (DR) of methane and finally a catalytic dehydrogenation (CDH) of methane. The last process is a single step process that in addition to high purity hydrogen also produces a valuable carbon nanotube byproduct.

Our work has made it clear, that technologies like POX and ATR due to their exothermic nature are much less sensitive to changes in heating utility cost like the recent spike in natural gas prices. However it is worth noting that all processes can be improved immensely by implementing process integration. An economic analysis of all the generated case studies was performed to evaluate the hydrogen production cost. It was found that the current technologies for producing hydrogen from liquid fuels are not attractive if evaluated only on the production cost. Benefits such as transportability etc. will need to be quantified for all types of fuel in order to better compare the technologies. The environmental impact for each process is evaluated and compared. The results show that SCWR of biomass is most environmental friendly compared to the other processes. Several technologies as being developed by CFFS researchers appear to be potentially cheaper alternatives to the current state of the art.