Distributed plasma-water-based nitrogen fixation system based on cascade discharge: Generation, regulation, and application

Plasma is a clean, environmentally friendly and low-energy-consumption technology that can be used to efficiently convert nitrogen gas (N2) into nitrogen compounds that can be absorbed by plants (such as NOx, NH3, etc.). However, most of the current research on plasma nitrogen fixation focuses on how to improve the yield and energy consumption of gaseous nitrogen fixation components. The research on gas treatment and absorption is still under development, which limits the development and application of distributed plasma nitrogen fixation devices. In this paper, we compared the combination methods of various discharge devices and found that the cascade discharge system of solar-driven dielectric barrier discharges (DBD) + 3-stage spark discharge can achieve high yield and low energy consumption of plasma-water-based nitrogen fixation. The measurement and simulation analysis of gaseous and aqueous plasma nitrogen fixation products shows that the oxidation of NO and NO2 (produced by spark discharge) by O3 (produced by DBD) is the working mechanism of the device to produce water-soluble N2O5. The aeroponics system developed based on this cascade discharge device has realized the aeroponics growth of lettuce, which has laid a certain theoretical and experimental foundation for the application development of distributed plasma nitrogen fixation.