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http://dx.doi.org/10.9713/kcer.2014.52.2.233

A Study on Ash Fusibility Temperature of Domestic Thermal Coal Implementing Thermo-Mechanical Analysis  

Lee, Soon-Ho (Energy Conversion System Lab/Pusan Clean Coal Center, Department of Mechanical Engineering, Pusan National University)
Lim, Ho (Energy Conversion System Lab/Pusan Clean Coal Center, Department of Mechanical Engineering, Pusan National University)
Kim, Sang Do (Clean Coal Center, Korea Institure of Energy Research)
Jeon, Chung-Hwan (Energy Conversion System Lab/Pusan Clean Coal Center, Department of Mechanical Engineering, Pusan National University)
Publication Information
Korean Chemical Engineering Research / v.52, no.2, 2014 , pp. 233-239 More about this Journal
Abstract
The slagging which generated from ash deposition on furnace wall and tube in boiler reduces the heat transfer efficiency and damages to safety of boiler. The slag flow behavior in boiler is affected by melting temperature which is related to ash compositions. In this study, the behavior of slag is researched by using ash fusibility test, called TMA (Thermo-Mechanical Analysis). The technique measures the percentage shrinkage as the function of temperature, T25%, T50%, T75%, T90%. These temperatures indicate different stages of melting. Then, the effect of ash chemical compositions measured from XRF (X-ray Fluorescence Spectrometer) to ash fusion temperatures is discussed. Among the chemical compositions, refractory and fluxing influence on ash fusibility is described. High levels of refractory component and limited amount of fluxing components ($Fe_2O_3$, $K_2O$, CaO) increase overall melting temperatures. High $SiO_2/Al_2O_3$ ratio decrease high melting temperatures (T75%, T90%). Meanwhile, the presence of reasonable levels of fluxing components reduces overall melting temperature. A presence of fluxing component such as $K_2O$ and CaO is found to decrease the T25% values significantly. From this research, it is possible to make a reasonable explanation and prediction of ash fusion characteristic from analysis of TMA results and ash chemical compositions.
Keywords
Slagging; Thermo-mechanical Analysis; Ash Fusibility Temperature; Ash Component;
Citations & Related Records
Times Cited By KSCI : 3  (Citation Analysis)
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