Combustion pyrolysis of natural gas is a promising process for high value-added chemicals such as alkynes and olefins. This work introduces recent experimental and computational studies of a 2.5 kTA (thousand metric ton per year) two-stage combustion pyrolysis unit, and focuses on the role of mixing on pyrolysis. Temperature, pressure, and gas composition measurements were experimentally obtained at different mixer and pyrolysis reactor lengths. Kinetic studies indicate that fast mixing of the hot combustion gas and cracking natural gas streams to the optimum temperature window of about 2000 K promotes C₂₊ formation and minimizes partial oxidation. Computational Fluid Dynamics (CFD) reacting turbulent flow simulations using Reynolds Average Navier–Stokes (RANS) and Large Eddy Simulation (LES) approaches with a detailed reaction mechanism were conducted on the integrated reactor system including combustor, mixer, and pyrolysis reactor. Results show good agreement between the CFD simulation results and experimental data, and reveal that the overall C₂₊ yield decreases to ∼21% due to the delayed mixing, compared to ∼36% in the perfect mixing scenario. Detailed comparison between experimental and simulation results are discussed, and potential strategies for reactor design and performance improvements are suggested.

天然气的燃烧热解对于高附加值的化学物质（例如炔烃和烯烃）是很有前途的过程。这项工作介绍了一个2.5 kTA（千公吨/年）两级燃烧热解装置的最新实验和计算研究，并着重介绍了混合在热解中的作用。在不同的混合器和热解反应器长度下，通过实验获得了温度，压力和气体成分的测量值。动力学研究表明，将热燃烧气体和裂化天然气流快速混合至约2000 K的最佳温度范围可促进C_2+的形成并使部分氧化最小化。计算流体动力学（CFD）反应湍流在包括燃烧器，混合器和热解反应器在内的集成反应器系统上，进行了使用雷诺平均纳维–斯托克斯（RANS）和大涡模拟（LES）方法以及详细反应机理的流动模拟。结果表明，CFD模拟结果与实验数据之间具有很好的一致性，并且表明，由于延迟混合，总的C ₂₊收率降低至〜21％，而理想混合情况下约为36％。讨论了实验结果和模拟结果之间的详细比较，并提出了用于反应堆设计和性能改进的潜在策略。