Resultados descriptivos

A comprehensive three dimensional full loop numerical model has been developed to simulate the flow dynamics characteristics of a novel in situ gasification chemical looping combustion (iG- CLC) system. This model is mainly composed of a high-flux circulating fluidized bed (HFCFB) riser as the fuel reactor (FR), a counter-flow moving bed (CFMB) as the air reactor (AR), an inertial separator, a J-valve and a downcomer. A two-stage AR was first proposed to enhance the power capacity of the system. The effects of the modeling parameters on the solids mass flux and solids distribution were studied in detail. The modeling results have presented favorable operation performance in terms of gas-solids flow behaviors and pressure distribution. The following conclusions can be drawn from the present study:

dimensional full loop iG-CLC model to predict reasonable gas-solids flow behaviors.

(2) The continuous and stable solids circulation was successfully realized along the path of “J- valve - FR - Inertial separator - Downcomer - AR - Downcomer - J-valve”. The high-flux solids circulation was innovatively achieved in the aspect of the full loop iG-CLC simulations to enhance the performances of reaction and heat transfer of the oxygen carrier. The FR and AR achieved intense turbulence and steady near plug flow, respectively.

(3) The power capacity of the iG-CLC system was successfully increased by coupling a two-stage AR. In addition, the optimized system also exhibited continuous solids circulation, reasonable pressure distribution and favorable operation performance.

AUTHOR INFORMATION

Corresponding Author

* Email: [email protected] (Baosheng Jin) * Email: [email protected] (Yong Zhang)

Notes

The authors declare no competing financial interest ACKNOWLEDGMENT

This work has been financially supported by the National Natural Science Foundation of China (51676038, 51741603, and 51276038), Natural Science Foundation of Jiangsu Province (BK20170669), Fundamental Research Funds for the Central Universities, and Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development (Y707s41001).

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For Table of Contents Only

Air Inlet of AR F u e l R ea c to r (F R ) A ir R e a c to r (A R ) Inertial Separator J-valve Gas Outlet of FR Gas Outlet of AR Downcomer Numerical Model iG-CLC Schematic Gasifying Agent Inlet of J-valve