Performances of a new type high-temperature tubular electrostatic precipitator with rare-earth tungsten cathode

• High temperature dust removal of rare earth tungsten cathode ESP was investigated. • Particles greater than 5 μm can be collected efficiently. • Dust collection efficiency is improved by increasing voltage or temperature. • Dust collection efficiency declines with increasing dust concentration. Dust removal experiments of rare earth tungsten cathode tubular electrostatic precipitators (ESPs) were carried out at high temperatures from 1073 to 1373 K. The impact of various factors on dust collection efficiency was investigated. The results show that at temperature of 1173 K and working voltage of 4000 V, the dust collection efficiency of La-W cathode single tube ESP can reach 98.22% on coal-fired power plant flying ash. Compared with the single tube ESP, the dust collection efficiency of a double tube ESP is improved. Although the tubular rare earth tungsten cathode high-temperature ESPs have higher collection efficiency for particles greater than 5 μm, they can’t collect fine particles smaller than 5 μm efficiently due to the limitation of their maximum working voltage. With rise of working voltage or temperature, the collection efficiency mainly shows evident increase tendency, while a little decrease with increasing temperature at higher temperature and lower voltage. Larger anode tube presents lower collection efficiency. Higher dust concentration leads to lower dust collection efficiency due to particle accumulation and deposition on the cathode surface. At low voltage (<3500 V), the dust collection efficiency can be significantly enhanced by extending the rare earth tungsten cathode.