Methane reforming by direct solar irradiation of the catalyst

2014

As demand for energy continues to rise, the concern over the increase in emissions grows, prompting much interest in using renewable energy resources such as solar energy. However, there are numerous issues with using solar energy including intermittancy and the need for storage. A potential solution is the concept of hybrid solar-fossil fuel power generation. Previous work has shown that utilizing solar reforming in conventional power cycles has higher performance compared to other integration methods. Most previous studies have focused on steam or dry reforming and on specific component analysis rather than a systems level analysis. In this article, a system analysis of a hybrid cycle utilizing redox reforming is presented.Important cycle design and operation parameters such as the oxidation temperature and reformer operating pressure are identified and their effect on both the reformer and cycle performance is discussed. Simulation results show that increasing oxidation temperature can improve reformer and cycle efficiency. Also shown is that increasing the amount of reforming water leads to a higher reformer efficiency, but can be detrimental to cycle efficiency depending on how the reforming water is utilized.

Section: + H 2 O(v) → Mo + H 2 (Exothermic or Endothermic)mentioning

confidence: 99%

Redox reforming based, integrated solar-natural gas plants: Reforming and thermodynamic cycle efficiency

2014

“…While the previous studies have utilized a porous disk type absorber, there have also been studies comparing the performance of a honeycomb and porous disk absorber within a directly heated dry reformer [58]. In the study by Levy et al a catalytic absorber was placed in a bell jar and then heated using a solar furnace.…”

Section: Dry Reforming With Honeycomb Absorber [58]mentioning

confidence: 99%

“…From various measurements the furnace used can attain a concentration ratio over 11,000 suns [58]. The bell jar receiver was made of fused silica and enclosed the catalytic absorber ( Figure 14).…”

Section: Dry Reforming With Honeycomb Absorber [58]mentioning

confidence: 99%

See 1 more Smart Citation

A review of solar methane reforming systems

Mokheimer

2015

124

Because of the increasing demand for energy and the associated rise in greenhouse gas emissions, there is much interest in the use of renewable sources such as solar energy in electricity and fuels generation. One problem with solar energy, however, is that it is difficult to economically convert the radiation into usable energy at the desired locations and times, both daily and seasonally. One method to overcome this space-time intermittency is through the production of chemical fuels. In particular, solar reforming is a promising method for producing chemical fuels by reforming and/or water/carbon dioxide splitting. In this paper, a review of solar reforming systems is presented, as well as a comparison between these systems and a discussion on areas for potential innovation including chemical looping and membrane reactors. Moreover, a brief overview of catalysis in the context of reforming is presented.

“…There has been much previous work on solar steam and dry reformers [4,5,6,7,8,9,10,11] as well as redox reformers [12,13,14,15,16,17]. System level studies have also been performed for steam and redox reformer hybrid cycles [2,3,18].…”

Section: Introductionmentioning

confidence: 99%

Dry redox reforming hybrid power cycle: Performance analysis and comparison to steam redox reforming

Mokheimer

2015

There has been much interest in the use of renewable resources for power generation as the world's energy demand and the concern over the rise in emissions increases. In the near term, however, renewable sources such as solar energy are expected to provide a small fraction of the world's energy demand due to intermittancy and storage problems. A potential solution is the use of hybrid solar-fossil fuel power generation.Previous work has shown the potential of steam redox reforming for hybridization.However, this type of reforming requires some water consumption (which may be infeasible in certain locations) as not all the water can be recovered through recy-cling. An alternative is to utilize dry (or CO 2 ) redox reforming. In this paper, a system analysis for a CO 2 redox reforming hybrid cycle and comparison of cycle and reformer performance between a CO 2 redox reformer and steam redox reformer hybrid cycle are presented. The effect of important operating parameters such as pressure, amount of reforming CO 2 , and the oxidation temperature on the reformer and cycle performance are discussed. Simulation results show that increasing the oxidation temperature or the amount of reforming CO 2 leads to higher reformer and * Corresponding Author: ghoniem@mit.edu, Tel: +1 6172532295, Fax: +1 6172535981 Preprint submitted to International Journal of Hydrogen EnergyOctober 24, 2014 cycle efficiencies. In addition, the comparison between the CO 2 and steam redox reformer hybrid cycles shows that the CO 2 cycle has the potential to have better overall performance.