主动冷却通道内吸热型碳氢燃料热裂解结焦抑制机理

Inhibition Mechanism of Pyrolytic Cokes from Endothermic Hydrocarbon Fuels in Regenerative Cooling Channels

为阐明超临界条件下吸热型碳氢燃料的热裂解结焦抑制机理,在电加热管实验装置上,获得了沿程油温、壁温以及燃料的组成,分析了结焦抑制添加剂影响碳氢燃料高温裂解和结焦的实验数据。结果表明:结焦抑制添加剂对碳氢燃料的裂解影响小于4%,降低结焦量约30%;添加结焦抑制剂后,结焦速率下降较快,稳定结焦速率降低约2%。采用SEM表征结焦抑制添加剂对结焦形貌的影响。结果表明,添加剂同时抑制了表面催化结焦与自由基生长结焦的形成。

To illuminate inhibition mechanism of pyrolytic cokes from endothermic hydrocarbon under supercritical conditions, the effects of coke- inhibiting additive on fuel cracking and formation of cokes were experimentally investigated by using electrically heated tube test and measuring the amount of cokes deposited on the wall at different time-on-stream（TOS = 0 -20 rain）. More information on the chemical compositions, temperatures of wall and cracked fuel along the tube were also provided. Adding coke - inhibiting additive decreases the cracking conversion by 4% , however, significantly reduces the amount of coking deposit by about 30%. After adding coke-inhibiting additive, the rate of coking formation drops faster and becomes about 2% lower. The characterization of carbon deposits morphologies by SEM shows that cokes formed through both surface catalysis and radical-growth mechanism are inhibited to some extent in the presence of coke-inhibiting additives.