松木颗粒流态化两段气化制备清洁燃气的工艺稳定性验证

Process stability verification of the two-stage fluidized bed gasification for pine particles to produce clean gas

为了验证流态化两段气化工艺的长时间运行稳定性,本实验采用商用果木炭半焦作为松木流态化两段气化制备清洁燃气的催化床料。实验前期通过形成稳定的有效催化半焦床层,减少半焦在系统内的积累周期,以实现系统快速达到高效脱除焦油的目的。实验中,保持过量空气系数(ER)为0.35,提升管气速为3m/s,并逐渐调整流化介质中的氧气浓度,逐步增大生物质处理量。结果显示,随着松木颗粒的进料量从1kg/h增大到3kg/h,产品气中CO和H2体积分数分别从7.71%和3.13%增长至16.15%和12.60%,CH4的体积分数略微下降。气体收率(标准)也从0.90m^(3)/kg增长至1.36m^(3)/kg,相应的产品气热值(标准)从3.26MJ/m^(3)增加至4.80MJ/m^(3)。通过多次人为启停和改变运行参数等操作,在整个12h运行周期内,流态化两段气化产生的半焦与消耗的半焦速度相匹配,温度和压力表现出良好的运行稳定性。这一结果证明了流态化两段气化工艺在生物质制气中具有技术先进性和长时间运行稳定性。

In order to verify the long-term operation stability of the two-stage fluidized bed gasification process,commercial fruit charcoal semi-coke is used as the catalytic bed material for the preparation of clean gas by pine fluidized two-stage gasification in this experiment.In the early stage of the experiment,a stable and effective catalytic semi-coke bed layer is formed to reduce the accumulation period of semi-coke,so as to quickly reach high-efficiency tar removal in the system.The excess air coefficient(ER)is maintained at 0.35,the gas velocity in the riser is 3m/s,and the oxygen concentration in the fluidization medium is gradually adjusted to gradually increase the biomass processing capacity.The results show that as the feed rate of pine particles increases from 1kg/h to 3kg/h,the volume percentages of CO and H2 in the product gas increase from 7.71% and 3.13% to 16.15% and 12.60%,respectively,while the volume percentage of CH4 slightly decreases.The gas yield also increases from 0.90m^(3)/kg to 1.36m^(3)/kg,and the corresponding calorific value of the product gas increases from 3.26MJ/m^(3)to 4.80MJ/m^(3).Through multiple manual start-stop and change of operating parameters,during the entire 12h operating cycle,the semi coke produced by the fluidized two-stage gasification matches the speed of semi-coke consumption,and the temperature and pressure show good operating stability.This result proves that the two-stage fluidized bed gasification process has technological advancement and long-term operation stability in the production of gas from biomass.