摘要
氨(NH_(3))的分解是其燃烧过程中的关键步骤。本文在鼓泡流化床(bubbling fluidized bed,BFB)反应器中系统地研究了反应器温度(650~950℃)、流化数(0.83~2.50)、床层高度(0~25mm)、入口NH_(3)流量(0~500mL/min)和床料成分(SiO_(2)、Al_(2)O_(3)、CaO、Fe_(2)O_(3))对NH_(3)分解特性的影响,旨在揭示流化床操作参数对氨分解特性的影响。通过气相色谱仪检测尾气中H_(2)和N_(2)的浓度。研究表明,以SiO_(2)为床料时,NH_(3)的分解率在650℃时仅为0.26%~0.29%,但在950℃时显著提高至18.1%~25.3%,升高温度在很大程度上有助于促进NH_(3)的分解。当流化数从0.83增至2.5时,由于有效气固接触时间的变化,NH_(3)分解率呈先升高后降低的趋势;最高的NH_(3)分解率为20.66%,且出现在临界流化状态。此外,床料颗粒在增强NH_(3)分解率方面具有重要作用。增加反应器内床料高度,可促进NH_(3)分解。另外,床料成分对NH_(3)分解的促进效果从大到小依次为Fe_(2)O_(3)>CaO>Al_(2)O_(3)>SiO_(2),均高于不添加床料的空床工况。本文的研究结果有助于深化对NH_(3)分解的认识,为流化床NH_(3)燃烧过程的调控提供理论基础。
Ammonia(NH_(3))dissociation is a crucial first step during its combustion process.This study systematically investigated the effects of reactor temperature(650—950℃),fluidization number(0.83—2.50),static bed depth(0—25mm),inlet NH_(3)flow rate(0—500mL/min),and bed material composition(SiO_(2),Al_(2)O_(3),CaO,Fe_(2)O_(3))on NH_(3)dissociation characteristics in a bubbling fluidized bed(BFB)reactor,which aimed to reveal how fluidized bed operating parameters influenced NH_(3)dissociation.The concentrations of H_(2)and N_(2) in the exhaust gas were measured by gas chromatography.The results showed that when SiO_(2)was used as the bed material,the NH_(3)conversion was only 0.26%—0.29% at 650℃,but it significantly increased to 18.1%—25.3% at 950℃,with higher temperatures greatly promoting NH_(3)dissociation.As the fluidization number increased from 0.83 to 2.5,the NH_(3)conversion first increased and then decreased due to changes in the effective gas-solid contact time.The highest NH_(3)conversion of 20.66%occurred at the incipient fluidization state.Additionally,bed material particles played an important role in enhancing NH_(3)dissociation.Increasing the static bed depth in the reactor promoted NH_(3)dissociation.Furthermore,the promoting effects of bed material composition on NH_(3)dissociation followed the order:Fe_(2)O_(3)>CaO>Al_(2)O_(3)>SiO_(2),all of which were higher than the empty bed condition.The findings could help deepen the understanding of NH_(3)dissociation and provide a theoretical basis for controlling the NH_(3)combustion process in fluidized beds.
作者
郭子鹏
李建波
赵梦佳
曹嘉
王泉海
卢啸风
GUO Zipeng;LI Jianbo;ZHAO Mengjia;CAO Jia;WANG Quanhai;LU Xiaofeng(Key Laboratory of Low-grade Energy Utilization Technologies and Systems of Ministry of Education,Chongqing University,Chongqing 400044,China)
出处
《化工进展》
北大核心
2026年第2期789-798,共10页
Chemical Industry and Engineering Progress
基金
国家外国专家个人类项目(S20240303)。
关键词
氨
鼓泡流化床
分解
NH_(3)分解率
有效气固接触时间
ammonia
bubbling fluidized bed(BFB)
dissociation
NH_(3)dissociation
effective gas-solid contact time
