The greenhouse problem has a significant effect on our communities such as,health and climate.Carbon dioxide is one of the main gases that cause global warming.Therefore,CO2 capture techniques have been the focus of a...The greenhouse problem has a significant effect on our communities such as,health and climate.Carbon dioxide is one of the main gases that cause global warming.Therefore,CO2 capture techniques have been the focus of attention these days.The chemical looping combustion technique adopted the air reactor and fuel reactor to recycle heat energy.This study presents a numerical and experimental investigation on a fuel reactor in chemical looping combustor(CLC)system.The present numerical model is introduced by the kinetic theory of granular flow and coupled with gas–solid flow with chemical reactions to simulate the combustion of solids in the CLC.The k–εturbulent model was used to model the gas phase and the particle phase.The developed model simplify the prediction of flow patterns,particle velocities,gas velocities,and composition profiles of gas products and the distribution of heterogeneous reaction rates under the same operating conditions.The predicted and experimental results were compared according to the basis of determination coefficient(R2).In addition the results showed that there is a good agreement between the predicted and experimental data.The value of(R2)for CO,CO2 and CH4 was 0.959,0.925 and 0.969 respectively.This shows that the present model is a promising simulation for solid particle combustion and gives the power direction for the design and optimization of the CLC systems.展开更多
With the help of Aspen Plus,a two-dimensional unsteady CFD model is developed to simulate the coal gasification process in a fixed bed gasifier.A developed and validated two dimensional CFD model for coal gasification...With the help of Aspen Plus,a two-dimensional unsteady CFD model is developed to simulate the coal gasification process in a fixed bed gasifier.A developed and validated two dimensional CFD model for coal gasification has been used to predict and assess the viability of the syngas generation from coal gasification employing the updraft fixed bed gasifier.The process rate model and the sub-model of gas generation are determined.The particle size variation and char burning during gasification are also taken into account.In order to verify the model and increase the understanding of gasification characteristics,a set of experiments and numerical comparisons have been carried out.The simulated results in the bed are used to predict the composition of syngas and the conversion of carbon.The model proposed in this paper is a promising tool for simulating the coal gasification process in a fixed bed gasifier.展开更多
文摘The greenhouse problem has a significant effect on our communities such as,health and climate.Carbon dioxide is one of the main gases that cause global warming.Therefore,CO2 capture techniques have been the focus of attention these days.The chemical looping combustion technique adopted the air reactor and fuel reactor to recycle heat energy.This study presents a numerical and experimental investigation on a fuel reactor in chemical looping combustor(CLC)system.The present numerical model is introduced by the kinetic theory of granular flow and coupled with gas–solid flow with chemical reactions to simulate the combustion of solids in the CLC.The k–εturbulent model was used to model the gas phase and the particle phase.The developed model simplify the prediction of flow patterns,particle velocities,gas velocities,and composition profiles of gas products and the distribution of heterogeneous reaction rates under the same operating conditions.The predicted and experimental results were compared according to the basis of determination coefficient(R2).In addition the results showed that there is a good agreement between the predicted and experimental data.The value of(R2)for CO,CO2 and CH4 was 0.959,0.925 and 0.969 respectively.This shows that the present model is a promising simulation for solid particle combustion and gives the power direction for the design and optimization of the CLC systems.
基金The research was supported by the National Key Research and Development Project(2016YFB060040202).
文摘With the help of Aspen Plus,a two-dimensional unsteady CFD model is developed to simulate the coal gasification process in a fixed bed gasifier.A developed and validated two dimensional CFD model for coal gasification has been used to predict and assess the viability of the syngas generation from coal gasification employing the updraft fixed bed gasifier.The process rate model and the sub-model of gas generation are determined.The particle size variation and char burning during gasification are also taken into account.In order to verify the model and increase the understanding of gasification characteristics,a set of experiments and numerical comparisons have been carried out.The simulated results in the bed are used to predict the composition of syngas and the conversion of carbon.The model proposed in this paper is a promising tool for simulating the coal gasification process in a fixed bed gasifier.