生物质快速热裂解主要参数对产物产率及其分布的影响

在生物质喂入率为0.8～2.0 kg·h^-1的流化床上以木屑为原料进行了快速热裂解试验，系统研究了木屑热裂解过程中的流化床反应器温度、生物质粒径和气相滞留期三个主要参数对热裂解产物产率的影响。结果表明，当反应器温度在450～600℃之间变化时，在500℃条件下，生物油产率最高，其值为53.33%，而木炭及不可冷凝气体产率分别为8.97%和37.70%。当温度为500℃，木屑粒径在0.90 mm以下时，粒径在0.45～0.60 mm范围内的生物油产率最大，达到58.23%，这时木炭产率为8.23%。对粒径小于0.20 mm的木屑在温度500℃，气相滞留期0.80, 1.20, 1.50 s三个量级上的热裂解表明，气相滞留期为0.80 s时，生物油产率达到最大值为62.60%。但是，当气相滞留期较长时(1.50 s)，生物油产率稍有下降。生物油是极性有机物与水的可溶混合物。因此，木屑快速热裂解生产液体燃料具有较大的潜力。

Effects of biomass fast pyrolysis key parameters on yields and distributions of products

Sawdust fast pyrolysis experiments were conducted in a fluidized bed reactor at a biomass feed rate of 0.80～2.00 kg*h-1. The effects of process conditions, like fluidized bed reactor temperature, feed size and vapor residence time on the product yields were studied. When reactor temperatures were varied from 450℃ to 600℃, a maximum bio-oil yield of 53.33%wt was achieved at 500℃ with a char and gaseous yields of 8.97 %wt and 37.70%wt respectively. The particle size of sawdust varied in the range of 0～0.90 mm. The yield of bio-oil was maximum (58.23%wt of biomass feed) for the particle size of 0.45～0.60 mm with a char yield of 8.23%wt. Vapor residence times were ranged from 0.80 to 1.50 s at temperature of 500℃ with a particle size less than 0.20 mm. A maximum bio-oil yield of 62.60%wt was achieved at 500℃ when the vapor residence time was held constant at 0.80 s. However, at the longer residence time(1.50 s), bio-oil yield was slightly lower. Bio-oil is a miscible mixture of polar organics with water. The results showed the potential of sawdust fast pyrolysis for liquid hydrocarbon fuels production.