Suspended Particle Purification by Negative Corona Discharges of Multi-needle Electrode

PM
2.5
and other fine particles are one of the indoor air pollutants that pose a great threat to human health. Long-term exposure to dust will cause heart and lung diseases and even cancer. A large number of high-energy electrons and active particles in low-temperature plasma can directly act on harmful substances in the air, which has high potential in purifying PM
2.5
. In order to achieve high purification efficiency of PM
2.5
, multi-needle electrode was used to generate large area plasma through negative DC corona discharge, and the purification characteristics of PM
2.5
were investigated. It is found that increasing the number of electrode needles can improve the purification efficiency of PM
2.5
under different applied voltages, but saturation effect may exist. The electrode humidity will affect the efficiency of PM
2.5
, and the efficiency in wet state is slightly higher than that in dry state.