YANG Jianmeng, LU Xuao, XU Gang, et al. Simulation and analysis of gasification process of biomass coke particles[J]. Thermal power generation, 2020, 49(7): 41-47.
DOI:
YANG Jianmeng, LU Xuao, XU Gang, et al. Simulation and analysis of gasification process of biomass coke particles[J]. Thermal power generation, 2020, 49(7): 41-47. DOI: 10.19666/j.rlfd.201909261.
Simulation and analysis of gasification process of biomass coke particles
摘要
生物质能源的合理利用对减少环境污染和碳减排具有重要意义。本文利用气化过程的随机孔模型为工具
进行了半焦颗粒气化过程的数值计算
并对半焦气化的相关准则数进行了分析。结果表明:在1 123 K气化温度下
颗粒半径小于0.26 mm时气化过程由化学反应过程控制
颗粒半径在0.26~1.45mm范围时由化学反应过程和CO_2扩散过程共同控制
当颗粒半径大于1.45 mm时
由CO_2扩散过程控制;气化温度在973~1 223 K时
随温度升高
CO_2的扩散过程对反应速率的影响逐渐增大
温度超过1223K时
CO_2扩散过程成为影响气化反应速率的主要因素。在实际气化中
可以采取减少焦炭粒径的方法加速气化过程
粒径应当控制在1.45 mm以下;如果颗粒粒径小于0.26 mm时可采取升高气化温度的方法加速气化
防止气化速率完全由CO_2扩散过程控制;对于1 mm焦炭颗粒
应当保持气化温度低于1 223 K。
Abstract
Rational utilization of biomass energy is of great significance to reducing environmental pollution and carbon emission reduction. Using the stochastic pore model of gasification process as a tool
numerical calculation of semi-coke particles gasification process was carried out
and the relevant criteria of semi-coke gasification were analyzed. The main conclusions are as follows. At gasification temperature of 1 123 K
the gasification process is controlled by chemical reaction process when the particle radius is less than 0.26 mm
by both chemical reaction process and CO_2 diffusion process when the particle radius is 0.26~1.45 mm
and by CO_2 diffusion process when the particle radius is greater than 1.45 mm. When the gasification temperature is 973~1 223 K
the higher the temperature
the greater the influence of CO_2 diffusion on the reaction rate. When the temperature exceeds 1 223 K
the CO_2 diffusion becomes the main factor affecting the gasification reaction rate. In actual gasification
the method of reducing coke particle size can be adopted to accelerate the gasification process
and the particle size should be controlled below 1.45 mm. If the particle size is less than 0.26 mm
the gasification can be accelerated by increasing the gasification temperature to prevent the gasification rate from being completely controlled by the CO_2 diffusion process. For 1 mm coke particles
the gasification temperature should be kept below 1 223 K.