Enhancement of the acetylene and ethylene yields from ethane by partially decoupling the oxidation and pyrolysis reactions

摘要

Graphical abstractDisplay OmittedHighlights?Partially decoupled process (PDP) is proposed for efficient conversion of C2H6.?Simulations are carried out by CFD coupled with detailed reaction mechanism.?PDP has a higher C2H2+C2H4yield than POX and steam cracking processes.?Ethane DPD is less sensitive to mixing and reactor scale-up than methane PDP.AbstractThe ethane contained in wet shale gas is usually used to produce ethylene through the steam cracking process. In parallel, the partial oxidation (POX) of methane is the most important method to produce acetylene. In this paper, the feasibility of the POX process of ethane was first explored. The reaction pathway analysis showed that the exothermal oxidation and endothermic pyrolysis reactions were highly coupled, which limited the yield of C2species (C2H2+C2H4). To overcome this problem, a new process named partially decoupling process (PDP) was proposed to physically separate the heat supply and pyrolysis reactions in a jet-in-cross-flow (JICF) reactor. The computational fluid dynamics (CFD) coupled with a detailed reaction mechanism, the modified GRI 3.0, was applied to simulate the complex interaction between turbulent mixing and reactions. The results showed that a high combined yield of ethylene and acetylene (69%) could be obtained. The operating and reactor structural parameters were further optimized based on the CFD simulations. The maximum yield of C2products was found less sensitive to the mixing in the ethane PDP than in the methane PDP, making it easier to scale up the reactor for the ethane PDP.]]>