Timothy hay abundantly available in New Brunswick, Canada, is mostly used for animal feed and bedding. Upgrading biomass using Torrefaction method can offer benefits in its waste management, energy density and energy conversion efficiency. Temperature and residence time play an important role in the torrefaction process. Meanwhile, CO₂ gasification is also a promising thermochemical conversion process due to its potential to reduce net GHG emissions and tune syngas composition. This study investigates the impact of torrefaction parameters on isothermal and non‐isothermal CO₂ gasification of Timothy hay and spruce chars. Timothy hay chars exhibited higher CO₂ gasification reactivity than chars from spruce. The physicochemical properties analysis indicated that higher reactivity of Timothy hay char was mainly attributed to the high amount of alkali and alkaline earth metal (AAEM) content, relatively large BET surface area, a high number ofactive sites, and a low crystalline index. Moreover, in both experimental cases, char derived through a high heating rate and high residence time conditions exhibited improved gasification performance, which was attributed to the generation of large amounts of AAEM (Ca and K) and high specific surface area. Co‐gasification results during non‐isothermal processes under CO₂ showed the presence of larger interactions in coal char/Timothy hay char blends than that of coal char/spruce char blends. For both experimental conditions, interactions were enhanced once the char prepared from high heating rate and high residence time was gasified with coal char. Thus, the proposed approach is a sustainable way of conversion of Timothy hay under CO₂ environment.

中文翻译：

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提莫西干草和云杉木材焦在CO2环境下的气化性能

Timothy干草在加拿大新不伦瑞克省大量存在，主要用于动物饲料和铺垫。使用Torrefaction方法升级生物质可提供废物管理，能量密度和能量转换效率方面的优势。温度和停留时间在烘焙过程中起着重要作用。同时，由于CO ₂气化具有减少净温室气体排放和调节合成气组成的潜力，因此它也是一种有前途的热化学转化工艺。本研究调查了焙干参数对蒂莫西干草和云杉炭等温和非等温CO ₂气化的影响。蒂莫西·干草炭表现出更高的CO ₂含量气化反应性比云杉焦炭高。理化性质分析表明，蒂莫西干草炭的较高反应活性主要归因于碱金属和碱土金属（AAEM）含量高，BET表面积相对较大，活性位点数量高以及结晶指数低。而且，在两种实验情况下，通过高加热速率和高停留时间条件得到的炭都表现出改善的气化性能，这归因于大量AAEM（Ca和K）的产生和高比表面积。在CO ₂下非等温过程中的共气化结果结果表明，与煤焦/云杉炭混合物相比，煤焦/提莫西干草炭混合物中存在更大的相互作用。对于这两个实验条件，一旦用煤焦气化了由高加热速率和高停留时间制备的焦炭，相互作用就会增强。因此，提出的方法是蒂莫西干草在CO ₂环境下的可持续转化方式。