Overview of Fluidized Bed Reactor Modeling for Chemical Looping Combustion: Status and Research Needs

Abstract

Modeling of next-generation CO2 capture technology, namely, chemical looping combustion (CLC), in bubbling and circulating fluidized bed reactors is briefly reviewed, and a summary of published mathematical reactor models is presented. The emphasis is on a macroscopic modeling approach, which, aiming at both low computing times and accuracy of results, adopts a phenomenological view and combines transport equations with semiempirical correlations to describe the relevant fluidized bed phenomena, for example, gas–solid flow behavior, reaction characteristics, and thermal effects. Important aspects to be considered in the modeling of CLC in a dual fluidized bed reactor system are highlighted, together with indications of the research needs detected among the reviewed works. So far, semiempirical reactor models have been validated based on experimental results obtained at a larger scale of CLC technology, i.e, up to 0.15 MWth for gaseous fuels (syngas and methane) and up to 1 MWth for solid fuels (mainly coal). Overall, the model predictions agree reasonably well with experiments selected for validation, despite the various model formulations and input data. The research achieved in dynamic process simulation of CLC is very limited.

Research Progress and Perspectives of Solid Fuels Chemical Looping Reaction with Fe-Based Oxygen Carriers

“…In addition, the wear and reactivity of iron-based oxygen carriers in the long term reaction of fluidized beds are very important. 148 The development of iron oxide materials with enhanced antisintering and wear properties by optimizing the composition and adjusting the structure has become a hot research topic at home and abroad. 149,150 Hu et al 151 explored the origin of the sintering of Fe-based oxygen carrier on ZrO 2 supported Fe 2 O 3 by H 2 reduction.…”

“…Generally speaking, sintering metal-based materials is a physical process involving the migration of active metal crystals on the surface of the support, followed by coalescence into larger agglomerates. In addition, the wear and reactivity of iron-based oxygen carriers in the long term reaction of fluidized beds are very important . The development of iron oxide materials with enhanced antisintering and wear properties by optimizing the composition and adjusting the structure has become a hot research topic at home and abroad. , …”

2022 Pioneers in Energy Research: Anders Lyngfelt

“…There are eight papers on this topic. Peltola summarizes recent progress and future direction in fluidized bed reactor modeling for chemical looping combustion. Pröll reports the scaling of fluidized-bed-heated reformer tubes in steam methane reforming with chemical looping combustion.…”

Performance Evaluation of Torrefaction Coupled with a Chemical Looping Gasification Process under Autothermal Conditions: Flexible Syngas Production from Biomass

“…To meet the carbon neutrality goal in 2060, China has formulated measures to reduce carbon emissions. − To date, ’China’s energy supply depends on fossil fuels, including 56.0% coal, 18.5% oil, and 8.9% natural gas. , Therefore, expanding renewable energy sources will be an unavoidable choice for China. , Biomass is an ideal alternative to fossil fuels because of its renewable nature and carbon neutrality. , China has about 3.04 Gt dry biomass per year, which needs further exploration and utilization . If these resources are not utilized, their potential will be wasted and environmental problems could arise. , Biomass gasification is an attractive thermochemical conversion process . Similar to coal gasification, biomass gasification is a technology that converts biomass into syngas. , Air, pure oxygen, steam, or CO 2 are usually used as gasification agents in conventional processes, but they have inherent defects. , For example, air reduces a product’s heating value because it contains nitrogen, and producing pure oxygen and steam is an intensive energy consumption process. , Unlike steam and air gasification, CO 2 gasification is mainly done on a laboratory scale .…”