Numerical Simulation of Acetylene Production by Pyrolysis of Coal with Plasma Tangential Circular Jets

This paper aims to advance the achievement of industrial-scale efficient thermal decomposition of pulverized coal into acetylene utilizing arc plasma. A comprehensive physical model, incorporating detailed reaction mechanisms, has been constructed to elucidate the multi-field coupled interaction mechanism between coal particles and hydrogen plasma jets, alongside the millisecond-scale pyrolysis process. The core functionality of this model lies in elucidating the regulatory mechanisms through which distinct high-temperature zones within the reactor govern the elementary reactions pertaining to acetylene and tar. Building upon this, it further proposes a flow mixing optimization strategy: enhancing the contact area and duration between the > 2500 K region and pulverized coal. Additionally, the model clarifies the synergistic effects of the spatiotemporal characteristics of particle devolatilization in the main flow and near-wall regions under the tangential circular mixing regime on energy efficiency. Furthermore, by optimizing reactor structural parameters such as diameter, energy efficiency can be elevated to approximately 16%. This model establishes a robust framework for numerical simulations of future industrial-scale thermal plasma coal pyrolysis systems and offers pragmatic guidance for the industrialization of this technology.