Detailed kinetic modeling of chemical quenching processes of acetylene-rich gas at high temperature

- Introduced an integrated detailed kinetic mechanism for acetylene decomposition at high temperature.
- Revealed the general requirements in preserving acetylene during quenching processes.
- Discussed the co-production of acetylene and ethylene and energy re-utilization of chemical quenching method.
- Proposed a detailed propane-quenching optimization for pilot-plant acetylene production by plasma coal pyrolysis.

Quenching of acetylene-rich gas at high temperature is an essential step in most acetylene production processes. Different from traditional physical quenching methods (e.g., water spray), chemical quenching has the advantage of reusing the gas heat content and producing co-products while preventing acetylene from decomposing. In this work, a detailed kinetic mechanism was proposed to theoretically describe and reveal the chemical quenching process. Reactions of small hydrocarbons, PAHs growth and soot formation were taken into consideration to build the model, which was validated by reported data. Afterwards, an ideal PFR model was used to investigate the effects of different operating conditions, including temperature after quenching, quenching time, and quenching media. Furthermore, the proposed model was used to optimize the chemical quenching operation for a pilot-plant acetylene production process based on thermal plasma technique. The results showed that chemical quenching could effectively realize both energy re-utilization and ethylene co-production, while maintaining a satisfactory yield of acetylene.