生物质超临界水制氢的数值模拟

本文对生物质在超临界水环境下气化制氢过程提出简化的两相流物理化学模型,并利用该模型进行数值模拟.着重讨论了温度、颗粒半径对生成气体摩尔百分比、气化率的影响.数值结果表明,颗粒的半径主要影响生物质颗粒气化分解的速率,而温度主要影响颗粒气化产物进一步生成氢气的过程.颗粒越小,气化分解的速率越快.温度的影响主要集中在气相反应上,使得CO进一步转化为H2.本文的理论和数值结果对实际的制氢过程中的参数控制具有实用价值.

NUMERICAL SIMULATION ON HYDROGEN PRODUCTION FROM BIOMASS IN SUPERCRITICAL WATER

In this paper,a simple model on hydrogen production from biomass in supercritical water process is proposed based on two-phase flow theory and corresponding physical and chemical reaction processes.Employing this model,the effects of temperature and biomass size on gas mole fraction and gasification efficiency are discussed.Numerical results show that the biomass size mainly affects the rate of its gasification,while the temperature mainly affects the process of the gas productions further converting into the hydrogen.The smaller the particle is,the faster the rate of its decomposition is.The temperature affections are mainly on the gas phase reaction,making the CO convert into H_2 further.The theory and numerical results in this paper are valuable in the control parameter selection in the actual hydrogen production tests.