为以氨替代部分煤在锅炉中混合燃烧，既可实现燃煤电站大比例减煤，还能解决可再生能源大规模消纳问题。热解作为燃烧的重要阶段，深刻影响着煤/氨混燃着火特性。本文采用反应分子动力学（ReaxFF MD）方法研究了3000 K、3250 K和3500 K温度下煤热解、氨热解和煤/氨共热解特性，揭示煤/氨共热解协同作用机制。结果表明：煤显著降低了氨气热解的活化能，促进了氨气热解。煤热解生成自由基促进了NH3+M → NH2+H+M反应，进而促进了氨气分解生成H2。煤/氨共热解过程中氨气促进了煤热解挥发分的析出：氨气略微促进了煤热解焦油的生成，但显著促进了煤热解气体产物的生成。氨气主要促进了H2O、HCN和C2H2气体产物的生成，但对CO的生成基本没有影响，氨气还促进了煤热解有机气体产物的生成。本文研究结果表明煤/氨热解协同效应有利于煤/氨混燃稳定着火。

Replacing coal with ammonia for co-combustion in boilers can not only achieve a large proportion of coal reduction in coal-fired power plants, but also solve the problem of large-scale consumption of renewable energy. As an important stage of combustion, pyrolysis deeply affects the ignition characteristics of coal/ammonia co-combustion. In this paper, the reactive molecular dynamics (ReaxFF MD) method was used to study the characteristics of coal pyrolysis, ammonia pyrolysis, and coal/ammonia co-pyrolysis at 3000 K, 3250 K and 3500 K, to reveal the synergistic mechanism of coal/ammonia co-pyrolysis. The results indicate that coal significantly reduces the activation energy of ammonia pyrolysis and promotes ammonia pyrolysis. The generation of free radicals from coal pyrolysis promotes the NH3 + M → NH2 + H + M reaction, thereby promoting the decomposition of ammonia to generate H2. During coal/ammonia co-pyrolysis, ammonia promotes the release of coal pyrolysis volatiles: ammonia slightly promotes the generation of coal pyrolysis tar, but significantly promotes the generation of coal pyrolysis gas products. Ammonia mainly promotes the generation of H2O, HCN, and C2H2 gas products, but has little effect on the generation of CO. Ammonia also promotes the generation of organic gas products from coal pyrolysis. The research results of this article indicate that the synergistic effect of coal/ammonia co-pyrolysis is beneficial for stable ignition of coal/ammonia co-combustion.

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