【摘要】 生物质的燃烧利用已被人们所重视,大量的生物质秸秆更需要合理的利用,而对于生物质秸秆燃烧锅炉,目前研究则不多。通过一系列秸秆在循环流化床内的燃烧实验,从秸秆颗粒度、密度以及表面粗糙度等方面研究了对其燃烧工况的影响。结果表明,颗粒度大小影响秸秆挥发分的析出以及传热过程,密度大小影响到原料的循环以及传热系数,表面粗糙度直接影响到秸秆的辐射换热。与煤相比,秸秆有其自身的特点,故生物质秸秆的循环流化床燃烧应根据其特点进行设计。考虑到秸秆的具体特性,流化床炉膛燃烧温度控制在800￣900℃之间为宜。更多还原

【Abstract】 Efficient conversion of straw materials for energy purpose has provided one ideal solution in wastes utilization and environment protection.The combustion characteristics of agricultural wastes in circulating fluid bed(CFB) were investigated with rice hull as the feedstock.On basis of long duration successive test with one pilot scale test facility,the effects of fluidizing velocity,particle size and air distribution on the combustion behavior were discussed in detail,as well as agglomeration phenomenon in straw material combustion.The variation of fluidizing velocity was found to be proportional to the variation of combustion efficiency in certain ranges.However,particle size was inversely proportional to combustion efficiency.And it seemed that the best ratio of secondary air in total air output was 50~70 percent for steady CFB operation In order to avoid the high temperature agglomeration in combustion process of straw materials in CFB,the operation temperature should be kept at below 900 ℃,with relatively uniform temperature distribution in CFB reactor under 850 ℃.更多还原