Improved slagging characteristics of low-value solid waste fuel asphalt rock by mineral additives of CaCO3, MgO, and Kaolin under fluidized bed condition

As a low-value solid waste fuel, asphalt rock is prone to slagging even under fluidized bed condition. The purpose of this study is to improve the slagging characteristics of asphalt rock by adding the mineral additives CaCO3, MgO, and Kaolin. The results showed that the K, Al, Ca salts in asphalt rock ash will evolve at different temperatures and exist mainly as K2SO4, KAlSiO4, Al2O3·SiO2, Al2O3, CaSO4, and CaSiO3. The CaSO4 formed from sulfur oxides and calcium-containing compounds is the main factor in asphalt rock slagging and can be facilitated by CaSiO3 with a small amount of CaCO3. The MgO can form MgCa(SiO3)2 with a high melting point and helps raise the ash fusion temperatures. In addition, the Kaolin will promote the formation of low-temperature eutectics, resulting in a slight decrease in ash fusion temperatures. Through optimization, it was found that with the addition of 9.0