Modeling of the Reduction of Hematite in the Chemical Looping Combustion of Methane using Barracuda [electronic resource]

• Ngôn ngữ: eng
• Ký hiệu phân loại: 623.8 Nautical engineering and seamanship
• Thông tin xuất bản: Morgantown, W.Va. : Oak Ridge, Tenn. : National Energy Technology Laboratory (U.S.) ; Distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy, 2016
• Mô tả vật lý: Size: p. 1221-1229 : , digital, PDF file.
• Bộ sưu tập: Metadata
• ID: 267782
• Chủ đề: 1. 01 coal, lignite, and peat; 2. 20 fossil-fueled power plants; 3. Chemical looping, reducer modeling

Tóm tắt

 Chemical looping combustion is a promising technology for the capture of CO<
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  involving reduction and oxidation of materials known as oxygen carriers. One particular carrier is hematite as it is readily available and relatively inexpensive as well as being non-toxic. The objective of this paper is to present a new particle model and reaction kinetics that can be applied to Barracuda� simulations of the fuel reactor. This was done since Barracuda does not allow for the JMA (nucleation and growth) type kinetics that were developed from analytical study the results from TGA and fixed bed experiments. This paper summarizes the analytical analysis of the fixed bed reduction experiments conducted in a cycling fixed bed reactor and subsequently modeled with Barracuda� CFD software to develop the new model. The experiments were conducted using nominally 1000 g of hematite material. The cyclic processing began with the reduction step then proceeded to the oxidation step repeating this analysis for several cycles (5 to 10). The effects of fuel partial pressure (8.4, 7.2 and 5 mole %) on the conversion were investigated. The JMA analysis assumed the reactions to occur in the shell surrounding the particle grains with diffusion of oxygen to the grain surface from the core. In contrast, working with the particle kinetics allowed in Barracuda�, the reactions occur with different hematite species (surface and core) homogeneously mixed. Therefore it is necessary to develop a new particle model with the rates being related to the amount of reactant (surface or core) in the particle. This paper presents the development of such a particle model and compares the results with experimental results.�