MOST- Novel microwave fluidized bed reactor for catalytic pyrolysis of biomass residues and biochar applications

据估计，不列颠哥伦比亚省每年有3000万吨森林残留物，这些残留物可以转化为高价值的液体生物燃料或生物化学品，以抵消与收集和预处理有关的高昂成本。热解是生物质在无氧条件下的热裂解过程，其将生物质转化为生物油和生物炭。生物油可以进一步升级为液体燃料。热解已被确定为将生物质残留物转化为生物燃料（柴油和喷气燃料）和生物化学品（例如碳、醇）的一种有前途的途径。然而，生物油和生物炭的低质量给升级和应用带来了挑战。具体而言，生物油中的高氧含量在升级操作中消耗大量氢气，这占与化石燃料制氢相关的整个液体生物燃料供应链中温室气体排放总量的66%以上。生物质炭的品质差也使其无法用作土壤肥料和冶金过程中的还原剂。在这个加拿大-台湾合作项目中，我们将开发一种新型的微波流化床反应器和低成本的天然催化剂，以就地热解生物质为生物油和生物炭。由于生物质颗粒独特的内部微波加热，以及热催化剂表面上的有机蒸气的原位微波辅助催化裂化，生物油的质量可以显著提高，如在我们的初步试验中的低氧含量、低酸度和低粘度所反映的。由于内部快速加热，产生了多孔结构和高比表面积的生物炭颗粒，其与作为营养物的剩余天然催化剂一起用作具有高水和营养物保持能力的高价值碳基肥料。即将开发的新型催化反应器系统将把丰富的生物质残渣转化为高质量的生物油和生物炭，为加拿大生物经济做出贡献，并有助于实现国家温室气体减排目标。

There are estimated 30 million tonnes of forest residues available each year at British Columbia, which can be converted to high-value liquid biofuels or biochemicals to offset the high cost associated with collection and pretreatment. Pyrolysis is a thermal cracking process of biomass in the absence of oxygen, which converts biomass to bio-oil and biochar. Bio-oil can be further upgraded to liquid fuels. Pyrolysis has been identified as a promising pathway for converting biomass residues to biofuels (diesel and jet fuel) and biochemicals (e.g. carbon, alcohols). The low quality of bio-oil and biochar, however, imposes challenges in upgrading and application. Specifically, the high oxygen content in bio-oil consumes large amount hydrogen in upgrading operation, which accounts for more than 66% of total greenhouse gas emissions over the whole liquid biofuel supply chain associated with hydrogen production from fossil fuels. The poor quality of biochar also surrenders its use as fertilizer for soil applications and as a reducing agent in metallurgical processes.In this Canada-Taiwan collaborative project, we will develop a novel microwave fluidized bed reactor and low-cost natural catalysts to in-situ pyrolyze biomass to bio-oil and biochar. Due to the unique internal microwave heating of biomass particles, and in-situ microwave-assisted catalytic cracking of organic vapours on hot catalyst surface, bio-oil quality can be improved significantly, as reflected by low oxygen content, low acidity and viscosity in our preliminary tests. Due to the internal rapid heating, the biochar particles of much porous structure and thus high specific surface area are created, which in conjunction with remaining natural catalysts as nutrients serve as a high-value carbon-based fertilizer with high water and nutrient holding capacity. The novel catalytic reactor system to be developed will convert abundant biomass residues to high-quality bio-oil and biochar, contributing to the Canadian bioeconomy, and contribute to meeting the national greenhouse emission reduction target.