Sorption-enhanced reforming of bioethanol in dual fixed bed reactor for continuous hydrogen production

Several problems with stabilization of electricity grid system are related to the time lag between the electricity supply and demand of the end users. Many power plants run for a limited period of time to compensate for increased electricity demand during peak hours. The amount of CO2 generated by these power installations can be substantially reduced via the development of new demand side management strategies utilizing CO2 absorption units with a short start-up time.The sorbent can be discharged using radiofrequency (RF) heating to fill the night-time valley in electricity demand helping in the stabilization of electricity grid. Herein a concept of RF heated fixed bed reactor has been demonstrated to remove CO2 from a flue gas using a CaCO3 sorbent. A very stable and reproducible operation has been observed over twenty absorptiondesorption cycles. The application of RF heating significantly reduced the transition time required for temperature excursions between the absorption and desorption cycles. The effect of flow reversal during desorption on desorption time has been investigated. The desorption time was reduced by 1.5 times in the revered flow mode and the total duration of a single absorption-desorption cycle was reduced by 20%. A reactor model describing the reduced desorption time has been developed. 2 Highlights• An RF reactor system has been demonstrated for post-combustion carbon capture.• The transition time between the absorption and desorption cycles was reduced by 2 times as compared to conventional heating• The reverse CO2 desorption flow mode reduced the desorption time by 1.5 times.• The energy efficiency of RF heated and conventionally heated bench reactors was compared

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“…The reaction of CO2 with CaO is stoichiometric and exothermic with the maximum theoretical absorption capacity of 79 wt.% [24]:…”

Section: Carbon Capture and Storage Technologiesmentioning

confidence: 99%

A radiofrequency heated reactor system for post-combustion carbon capture

Fernández

Sotenko

Derevschikov

et al. 2016

Chemical Engineering and Processing: Process Intensification

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“…Because the single fixed reactor for SESR needs switching between reforming and regeneration period, this is complicated for operation and maintenance. So for continuous reforming in general fixed bed reactor, parallel reactors systems are typically applied (Lysikov et al, 2015;Li et al, 2006). In the meanwhile, fluidized bed reactors have been developed.…”

mentioning

confidence: 99%

Computational fluid dynamic study of sorption enhanced steam reforming of methane/ethanol in circulating fluidized bed system

Phuakpunk

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Two-dimensional fluid dynamic models were used to optimize and design a proper pilot-scale system for sorption enhanced steam methane reforming (SESMR) and sorption enhanced steam reforming of ethanol (SESRE) in a circulating fluidized bed reactor (CFBR) using Ni-based catalyst and dolomite as sorbent. The CFBR system was separately designed as 3 parts: including a SESMR riser, a SESRE and a regenerator. The SESMR riser could get H2 purity reached equilibrium of 98.58% in dry basis with the highest H2 flux of 0.301 kg/m2s when operating with steam to carbon ratio of 4 mol/mol, gas velocity of 6 m/s, inlet temperature of 581?C. While the SESRE riser could get maximum H2 purity only 91.30% in dry basis with the highest H2 flux of 0.147 kg/m2s when operating with steam to ethanol ratio of 6 mol/mol, gas velocity of 3 m/s, inlet temperature of 600?C. Both the risers for SESMR and SESRE had the best design with diameter of 0.2 m, height of 7 m operating with solid flux of 200 kg/m2s and catalyst to sorbent ratio of 2.54 kg/kg. Lastly, in regenerator part, double-stage bubbling bed regenerators with 1.2 m width and 0.8 m height of bed could perfectly regenerate the sorbent when operating with gas velocity of 0.2 m/s and preheating the solids at 950?C. Overall, SESMR and SESRE had feasibility to continuously produce high purity with high production rate of H2 by this preferred design and conditions of CFBR system.

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