Sensitivity analysis on the maximum ash resistivity in terms of its compositions and gaseous water concentration

Fly ash resistivity is one of the critical factors influencing its collection efficiency of electrostatic precipitators (ESPs). This paper discusses the resistivity in terms of ash compositions and water concentration and evaluates available resistivity models with over 120 groups of ashes. The analysis shows that the available models hardly match each other for predicating the resistivity. With regard to ash compositions, only Li2O plus Na2O and Fe2O3 have obvious effects on the maximum resistivity. A new simplifying model is proposed for approximating the maximum ash resistivity in terms of the ash compositions and the water concentration, which is used to size ESPs and to predicate the collection efficiency.

► We report the maximum ash resistivity with a group of over 120 types of Chinese Coal-fired fly ashes.
► With regard to ash compositions, only Li2O plus Na2O and Fe2O3 have obvious effects on the maximum resistivity.
► We build a simplifying model to approximate the maximum ash resistivity.