Abstract Pyrolysis is a clean and economical method to dispose meat and bone meal (MBM) from animal carcasses. However, the large quantity of nitrogen from the animal protein will lead to the formation of gaseous-N compounds such as NH3 and HCN, which are the precursors of NOx. In this study, the release behavior of these gaseous-N compounds during the pyrolysis of MBM was investigated using a temperature-programed tube reactor combined with an FTIR analyzer. Moreover, the formation mechanism of them was elucidated by examining the evolution of solid and liquid N-products with temperature. The result showed that 31.0% of the MBM was released as gaseous N including NH3, HCN and HNCO, among which NH3 accounted for 76.2% while HNCO was a minor product. NH3 was mainly released below 300 °C from the decomposition of ammonium and the polymerization of liable protein. On the other side, the nitriles and heterocyclic N-compounds identified in tar and char were the precursors of HCN and HNCO. The results provided basic data for the inhibition and removal of gaseous N-compounds during the pyrolysis of animal biomass.

中文翻译：

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肉骨粉热解过程中气态氮化合物的排放

摘要 热解是一种清洁、经济的处理动物尸体肉骨粉 (MBM) 的方法。然而，来自动物蛋白的大量氮会导致气态氮化合物的形成，如 NH3 和 HCN，它们是 NOx 的前体。在这项研究中，使用程序升温管式反应器结合 FTIR 分析仪研究了这些气态 N 化合物在 MBM 热解过程中的释放行为。此外，通过检查固体和液体 N 产物随温度的演变，阐明了它们的形成机制。结果表明，31.0% 的 MBM 以气态 N 形式释放，包括 NH3、HCN 和 HNCO，其中 NH3 占 76.2%，而 HNCO 是次要产物。NH3 主要在 300 °C 以下由铵的分解和易蛋白质的聚合释放。另一方面，在焦油和炭中鉴定出的腈和杂环 N 化合物是 HCN 和 HNCO 的前体。结果为动物生物质热解过程中气态氮化合物的抑制和去除提供了基础数据。