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煤与水生生物质及其混合物快速热解过程中氮迁移研究

Nitrogen Conversion During Rapid Pyrolysis of Coal, Aquatic Biomass and Their Blends

【作者】 李军

【导师】 王辅臣;

【作者基本信息】 华东理工大学 , 化学工艺, 2011, 硕士

【摘要】 本文利用高频热解装置对褐煤、烟煤和无烟煤三种不同煤阶的煤及模型化合物吡咯、吡啶、咔唑、吖啶、生物质蓝藻和水葫芦以及蓝藻和水葫芦在不同比例下与煤进行了热解实验,对快速热解过程中HCN和NH3以及Char-N产率进行分析,并且对煤热解过程中HCN和NH3以及Char-N逸出的影响因素进行了分析。(1)褐煤、烟煤的HCN产率随升温速率增加而降低,无烟煤的HCN产率随升温速率增加先增加后基本保持不变;褐煤、烟煤的NH3产率随升温速率增加而增加,无烟煤的NH3产率随升温速率增加降低。褐煤和烟煤的HCN产率随温度升高而降低,无烟煤的HCN产率随温度升高而增加;褐煤、烟煤、无烟煤的NH3产率随温度升高均先增加后降低。模型化合物吡咯快速热解时,NH3为主要的含氮产物,吡啶快速热解时,HCN为主要的含氮产物。(2)蓝藻和水葫芦中氮主要以蛋白质的形式存在,热解时主要的含氮污染物为NH3,也有少量的HCN生成,这是由于氨基酸分解时更易形成N、NH、NH2自由基,并且蓝藻和水葫芦热解时,能产生大量的H自由基,使得NH3产率高,蓝藻和水葫芦热解时HCN和Char-N产率均随温度的升高而降低,而NH3产率随温度的升高先升高后降低。(3)蓝藻和水葫芦与神府煤热解共热解时,可能是因为蓝藻和水葫芦中含有大量的CaO,促使了HCN还原反应生成NHi,而NHi进一步反应生成N2,这使得HCN和NH3产率较预估HCN、NH3产率低,而HCN产率随温度的升高而降低,NH3产率随着温度的升高先升高后降低。

【Abstract】 Pyrolysis of three kinds of the different rank of coal, four nitrogen model compounds of pyrrole, pyridine, carbazole, acridine, biomass of blue-green algae and water hyacinth together with three different ratios of biomass in Shenfu and Zunyi coal were carried out in a high-frequency furnace. The yields and influencing factors of HCN, NH3 and Char-N were analyzed, the thesis included the following three parts:(1) The yields of HCN during pyrolysis of lignite and bituminous decrease with an increasing heating rate, while HCN yield of anthracite increases and then to be constant with an increasing heating rate. NH3 yields of lignite and bituminous increase, while NH3 yield of anthracite decrease with an increasing heating rate. HCN yields of lignite and bituminous decrease, while HCN yield of anthracite increases with an increasing temperature. NH3 yields of lignite, bituminous and anthracite increase and then decrease with an increasing temperature. NH3 was the main nitrogen-containing product during the pyrolysis of pyrrole and carbazole, while HCN was the main nitrogen-containing product during the pyrolysis of pyridine and acridine.(2) The main nitrogen form in blue-green algae and water hyacinth is protein, NH3 is the main nitrogen-containing pollutant during pyrolysis, a small mount of HCN also is formed, lots of N. NH and NH2 are formed during decomposition of amino acid, a great amount of H are also formed during pyrolysis of blue-green algae and water hyacinth, so NH3 can be easily formed during pyrolysis of blue-green algae and water hyacinth leading a high yield of NH3. The yields of HCN and Char-N decrease with an increasing temperature, while the yields of NH3 increase and then decrease with the increased temperature.(3) HCN can be reduced to NHi and NHi finally converted to N2 during co-pyrolysis of blue-green algae and water hyacinth with Shenfu coal and Zunyi coal because of higher mount of CaO existed in blue-green algae and water hyacinth, so HCN and NH3 yields in the experimental are lower than that of calculated value. The yields of HCN decrease with the increased temperature, while NH3 yields increase and then decrease with an increasing temperature.

【关键词】 蓝藻水葫芦热解氮迁移
【Key words】 coalblue-green algaewater hyacinthpyrolysisnitrogen conversion
  • 【分类号】TQ534
  • 【下载频次】185
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