The emulsion mist purification system in a cold rolling workshop of a certain steel plant has a flue gas temperature of ≤ 80 ℃, contains oil mist and metal fine powder, and has no strong corrosiveness. Using polyester anti-static filter bags (with conductive fibers added) not only avoids oil mist adhesion, but also prevents static electricity accumulation from causing safety hazards. The filtration efficiency reaches 98%, and the filter bag has a lifespan of 2 years, which is more stable than ordinary filter materials.