Nitrogen is an essential element for living organisms
but in nature
it mainly exists in the stable form of nitrogen gas (N2)
which is difficult to be directly utilized. Therefore
it needs to be converted into nitrogen-containing compounds
a process known as nitrogen fixation. At present
industrial nitrogen fixation generally suffers from high energy consumption and serious pollution problems. To address this issue
a gas-driven gliding arc plasma device was designed in this study for efficient nitrogen fixation research. The discharge modes of the device include the steady arc gliding (A-G) mode and the breakdown gliding (B-G) mode. The voltage and current signals under different operating parameters were collected using an oscilloscope
and the discharge patterns of the two modes were recorded using a camera. The effects of power output
gas flow rate
and oxygen content in the feed gas on nitrogen fixation efficiency were systematically investigated
and the differences between the two discharge modes were compared. The results show that the B-G mode features lower energy consumption but a relatively low yield of nitrogen oxides
while the A-G mode can significantly increase the nitrogen oxide concentration but at a higher energy cost. Therefore
in practical applications
an appropriate discharge mode should be selected on the basis of specific requirements. By optimizing the discharge parameters
the volume fraction of nitrogen oxides is increased from 4 180×10−6 to 12 097×10−6
an improvement of about 189%
while the energy consumption for nitrogen fixation is decreased from 4.6 MJ/mol to 2.4 MJ/mol
a reduction of about 50%
significantly enhancing the plasma nitrogen fixation efficiency.