松木生物质颗粒预热燃烧特性试验  

Preheating and combustion characteristics of pine biomass particles

作　　者：章锦阳 欧阳子区 丁鸿亮[2,3] 苏坤 ZHANG Jinyang;OUYANG Ziqu;DING Hongiang;SU Kun(Research Center of Fluid Machinery Engineering and Technolagy,Jiangsu University,Zhenjiang212013,China;Institute of Engineering Thermophysics,Chinese Academy of Sciences,Beijing100190,China;University of Chinese Academy of Sciences,Beijing100049,China)

机构地区：[1]江苏大学流体机械工程技术研究中心,江苏镇江212013 [2]中国科学院工程热物理研究所,北京100190 [3]中国科学院大学,北京100049

出　　处：《洁净煤技术》2024年第7期127-134,共8页Clean Coal Technology

基　　金：中国科学院战略性先导科技专项资助项目(XDA29010200);中国科学院稳定支持基础研究领域青年团队计划资助项目(YSBR-028);中国科学院青年创新促进会资助项目(2019148)。

摘　　要：使用于松木生物质颗粒作为燃料,结合先进的自预热燃烧技术,实现燃料在炉膛内的流态化燃烧。通过千瓦级预热燃烧试验平台,对木本生物质颗粒在不同预热温度下的预热改性进行了全面深入的探索。使用BET、SEM扫描电镜与拉曼光谱带对比的方法对高温生物质半焦的比表面积、总孔容积、氮气等温吸附脱附特性、颗粒表明形态等关键物性参数进行检测和分析。分析结果显示,随着预热温度的升高,氮气吸附量明显增加,说明改性后的生物质半焦具有更多的孔隙结构。结合碳微晶结构分析,松木生物质颗粒在高加热速率下解聚脱挥发导致大分子碳链断裂产生小分子挥发物从而改善反应活性。在燃烧特性方面,改性后的高温生物质半焦可在下行燃烧室内迅速实现稳定燃烧,且燃烧效率高达99%以上。在NO_(x)排放上,所有实验工况均将燃烧温度控制在1 100℃以下避免产生热力型NO_(x)。预热后松木生物质颗粒的NO_(x)排放浓度并未随预热温度的单调变化而增减。842℃时,NO_(x)排放质量浓度达到峰值,随后开始下降。在试验温度范围内,当预热温度设定为705℃时,NO_(x)排放质量浓度达到最低值,即97.79 mg/m^(3)。综上,为确保松木生物质预热燃烧后具有较低的NO_(x)排放和高燃烧效率,推荐的最佳预热温度为705℃。Pine biomass particles as a fuel source and integrated advanced self-preheating combustion technology was employed to achieve fluidized combustion within the furnace.The preheating modifications of woody biomass particles under different preheating temperatures were examined using a kilowatt level preheating combustion test rig.BET,SEM scanning electron microscopy and Raman spectral band comparison methods were employed to detect and analyze the specific surface area,total pore volume,nitrogen isothermal adsorption and desorption characteristics,particle morphology and other key physical property parameters of high temperature biomass semi-coke.The findings indicate that an increase in preheating temperature results in a noticeable rise in nitrogen adsorption amount,suggesting that the modified biomass semi-coke possesses a more developed pore structure.The depolymerization and devolatilization of pine biomass par-ticles at high heating rates,combined with the analysis of carbon microcrystalline structure,result in the disruption of macromolecular car-bon chains and the generation of small molecular volatiles,thereby enhancing reactivity.The modified high-temperature biomass semi-coke exhibits rapid attainment of stable combustion within the descending combustion chamber,with a remarkable combustion effi-ciency reaching 99%in terms of its combustion characteristics.In terms of NO_(x) emissions,the combustion temperature is maintained at 1100℃under all experimental conditions to prevent the formation of thermal NO_(x).It is noteworthy that the concentration of NO_(x) emis-sions from pine biomass particles does not exhibit a linear relationship with preheating temperature.Specifically,at 842℃,the concentra-tion of NO_(x) emissions peaks and then begins to decrease.Within the range of test temperatures,when the preheating temperature is set at 705℃,the concentration of NO_(x) emissions reaches its lowest value,namely 97.79 mg/m^(3).In conclusion,for ensuring low NO_(x) emissions and high combustion efficiency

关 键 词：生物质颗粒 预热燃烧器 燃料改性 燃烧特性 NO_(x)排放 

分 类 号：TK16[动力工程及工程热物理—热能工程]