Abstract
Electrostatic beneficiation system of unbumed carbon &om fly ash for ash utilization was being developed and has testedusing a continuous, semi-demo scale separator composed of three distributors, four vertical electrode plates and an ejector-tribocharger. Performance test on the removal efficiency of unbumed carbon from coal fly ash at electroseparator of 3 ton/hr were performed under various and continuous operating conditions. Test results showed that clean ashes of 55%, 50%and 40% containing LOl 3% could be recovered from fly ash samples with 7.5%, 8% and 9% LOI, respectively. It wasfound that the relative humidity of the surrounding air and voltage leakage of between electrode and deposited chargingparticles on the splitter were the most influencing factors of the separation efficiency at experimental conditions; the airflow rate of46 mU/min, the solids loading of less than 1.16 kg/m\ 30% relative humidity and SLJS304 ejector tribocharger.Also, the optimum instrument conditions for recovering clean ash with less than 3% at yield over 55% when operated atabove experimental conditions were found to be the diffuser slit gap of 6mm, the air velocity in electric field of 4.9 ~ 5.5m/s, and the distance of between diffuser slit and splitter of 15 cm. In overall, solid loading per unit electrode surface areawas about 0.11 kg/cmU.hr, which can be used as a scale-up factor of demonstration scale electroseparator.