Co-production of pure hydrogen, carbon dioxide and nitrogen in a 10 kW fixed-bed chemical looping system

Abstract

Fixed-bed chemical looping for the generation of high purity hydrogen with sequestration of pure carbon dioxide and nitrogen.

Hydrogen Production from Biomass-Based Chemical Looping: A Critical Review and Perspectives

“…Similar work was also conducted by Zeng et al using lab-scale fixed bed reactors for CLHP reactions. On this basis, Bock et al , developed a 10 kW th fixed bed chemical looping H 2 production system, which features an upper catalytic section for reforming and a lower chemical looping section for H 2 production. During cyclic operation, this system achieves CO 2 and H 2 purities of approximately 99% and 99.997%, respectively, with a feedstock utilization rate of 0.6.…”

“…Diagram of the fixed bed reactor for the CLHP system. Reproduced with permission from ref . Copyright 2020 Royal Society of Chemistry.…”

Review of pressurized chemical looping processes for power generation and chemical production with integrated CO2 capture

“…The main benefits of this reactor concept are that solids circulation and solids attrition are intrinsically avoided, more compact reactor design with ease of pressurization in a single vessel [86]. The disadvantages of the fixed-bed reactors are the requirement of a high temperature switching valve system (in most targeted processes), and highly exothermic oxidation reaction creates large transient thermal gradients that can damage the oxygen carrier by sintering or other defect on the morphological properties of the OC [87]. Additionally, larger particles should be used to minimize the pressure drop, which may lead to intra-particle diffusion limitation lowering the utilization of the oxygen carriers [88].…”

Comparative Analysis of Energy and CO2 Emission for the Integration of Biomass Gasification with a Dual-Reactor Chemical Looping Hydrogen Production Process

“…Moreover, Zacharias et al 16 showed that pure and pre-pressurized hydrogen can be produced in a fixed-bed microreactor with a release pressure of 20−25 bar, thereby significantly reducing the energy demand for H 2 compression in mobility applications. Currently, the CLHP process can produce hydrogen with a purity of ≥99.99%, 17 making it suitable for use as a feedstock for fuel cells or as a refrigerant for cooling power units after pressurization.…”

“…The three-reactor CLHP process involves the use of iron oxide as the OC, CO, and H 2 as the fuel for the following reactions, which can be completely converted to CO 2 and H 2 O in the presence of Fe 2 O 3 in the system: The development of CLHP systems has mostly been reported in the literature at the kilowatt scale, with compounded syngas being the preferred fuel source over biomass. Bock et al , designed a 10 kW th fixed-bed CLHP system, which achieved a feedstock utilization rate of 60% during the cycle operation, and the purity of CO 2 and H 2 obtained was approximately 99 and 99.997%, respectively. Fan’s research group investigated iron-based CLHP processes using different feedstock, such as coal, natural gas, and biomass, and employed counter-flow moving bed designs for the SR and FR, while the AR was designed as a fluidized bed. − The pilot high-pressure syngas CLHP plants of 25 and 250 kW th were successfully tested, and their feasibility was verified. , Xiang et al proposed a three-fluidized-bed reactor system, which achieved efficiencies of 14.46, 36.93, and 89.62% for electricity, hydrogen, and carbon capture, respectively.…”