Corncob is one of the most abundant agro-industrial wastes globally. It represents a bioenergy feedstock of 1500–5500 million tons per year. The shape and size of the corncob are suitable for gasification without pretreatment (size reduction, densification, or drying) in a downdraft gasifier. However, its volatile content (about 80% DAF) can generate high tar content, representing a challenge to adopt this technology. In the present work, an evaluation of the effect of air-steam mixture and calcium carbonate CaCO₃ as a promoter of both reforming and gasification reaction was carried out using corn cob without grains as raw material in a 40 kW gasifier. An analysis of variance of four experimental treatments was used to determine the main statistical and interactive effects on the syngas composition, hydrogen yield (yH₂), syngas lower heating value (LHV_gas), and cold gas efficiency (CGE). Results reveal the highest gasification performance achieved hydrogen production yields of 310 Nml/g, an LHV_gas value of 4.8 MJ/Nm³, and cold gas efficiency of 59.18% with steam and CaCO₃. Statistical analysis indicated that CaCO₃ and steam influence H₂ production by increasing 15.8% and 10.8%, respectively, with a CaCO₃/biomass ratio of 1% (w/w) and a Steam/biomass ratio of 11% (w/w). Main statistical effects were found for CGE increase of 5% with the addition of steam, 10% with CaCO_3, and synergy of 10% using CaCO₃ and steam simultaneously.

玉米芯是全球最丰富的农业工业废物之一。它代表了每年 1500-55 亿吨的生物能源原料。玉米芯的形状和尺寸适合在下吸式气化炉中无需预处理（粉碎、致密化或干燥）即可气化。然而，其挥发性成分（约 80% DAF）会产生高焦油含量，这对采用该技术提出了挑战。在目前的工作中，评价空气-蒸汽混合物和碳酸钙 CaCO _{3 的效果}以无谷玉米芯为原料，在 40 kW 气化炉中作为重整和气化反应的促进剂进行。四种实验处理的方差分析用于确定对合成气成分、氢气产率 (yH ₂ )、合成气低热值 (LHV _gas ) 和冷气效率 (CGE)的主要统计和交互影响。结果表明，最高气化性能实现了 310 Nml/g 的制氢产率、4.8 MJ/Nm ³的 LHV_气体值和 59.18% 的蒸汽和 CaCO ₃冷气效率。统计分析表明CaCO ₃和蒸汽对H ₂有影响产量分别增加 15.8% 和 10.8%，CaCO ₃ /生物质比为 1% (w/w)，蒸汽 / 生物质比为 11% (w/w)。被发现的5％CGE增加与加入蒸汽，用碳酸钙10％主要统计效应_3，和使用的CaCO 10％协同₃和蒸汽同时。