富氧条件下煤粉气流的着火性能变化  

Ignition characteristics of coal powder airflow under various oxygen-enriched conditions

作　　者：刘国伟[1] 董芃[1] 别如山[1] 

机构地区：[1]哈尔滨工业大学能源科学与工程学院,黑龙江哈尔滨150001

出　　处：《化工学报》2013年第7期2596-2603,共8页CIESC Journal

基　　金：黑龙江省自然科学基金重点项目(GC12A326)~~

摘　　要：利用一维火焰炉对不同富氧条件下的煤粉气流着火燃烧特性进行了研究,得到了富氧条件下煤粉气流的着火性能变化规律。研究结果表明:随着助燃气体氧浓度的提高,各煤样的着火温度均大幅下降,其中低挥发分煤种在着火方面对富氧条件的改善更为敏感,即富氧条件的改善可减弱煤种间着火性能方面的差异性;随着氧浓度的提高,煤粉气流的着火方式明显从均相着火向非均相着火转变,其中燃用褐煤时发生着火方式转变所对应的氧浓度为50%～60%,燃用烟煤时约为40%,燃用贫煤和无烟煤时都约为30%;对于烟煤和褐煤,随着氧浓度的提高,对应的最佳煤粉浓度值先增大后减小,而对于贫煤和无烟煤,由于其在整个实验氧浓度范围内基本上都以'非均相着火'为主,因此随着氧浓度的提高,对应的最佳煤粉浓度的值基本上呈缓慢下降的趋势。Ignition characteristics of coal powder airflow was investigated with a one dimensional furnace under various oxygen-enriched conditions,to get their changing laws.The results show that with oxygen concentration increases,ignition temperature of four kinds of coals decrease greatly and do faster for low volatile coals,and an obvious transformation is observed for ignition mode of pulverized coals,from homogeneous to heterogeneous,the oxygen concentrations corresponding to the transformation are about 40% for bitumite,50%—60% for lignite and about 30% for both lean coal and anthracite,respectively.With oxygen concentration increasing,the optimal coal powder concentrations increase first and then decrease for bituminous coal and lignite,but decrease slowly for lean coal and anthracite.

关 键 词：富氧 着火机理 着火特性 着火方式 

分 类 号：TK227.7[动力工程及工程热物理—动力机械及工程]