Park DK  Cho WC  Seo MW  Go KS  Kim SD  Kang KS  Park CS

Vol. 17,  No. 1, pp. 69-77, Mar.  2011

Intrinsic CO2 separation Hydrogen production process Conceptual Design Moving bed Hydrodynamics

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The intrinsic CO2 separation and hydrogen production system is a novel concept using oxidation and reduction reactions of oxygen carrier for both CO2 capture and high purity hydrogen production. The process consists of a fuel reactor (FR), a steam reactor (SR) and an air reactor (AR). The natural gas (CH4) is oxidized to C02 and steam by the oxygen carrier in FR, whereas the steam is reduced to hydrogen by oxidation of the reduced oxygen carrier in SR. The oxygen carrier is fully oxidized by air in AR. In the present study, the chemical looping moving bed reactor having 200 Lih hydrogen production capacity is designed and the hydrodynamic properties were determined. Compared with other reactors, two moving bed reactors (FR, SR) were used to obtain high conversion and selectivity of the oxygen carrier. The desirable solid circulation rates are calculated to bc in the range of 20-100 kg/m2s from the conceptual design. The solid circulation rate can be controlled by aeration in a loop-seal. To maintain the gas velocity in the moving beds (FR, SR) at the minimum fluidization velocity is found to be suitable for the stable operation. The solid holdup in moving beds decrease with increasing gas velocity and solid circulation rate.