Proceedings of an International Conference on Mitigation of Heat Exchanger Fouling and Its Economic and Environmental Implications

ISBN Print: 1-56700-172-6

LOW QUALITY COALS AND BLENDING: OPPORTUNITIES FOR MITIGATION OF FOULING

DOI: 10.1615/1-56700-172-6.130
pages 115-122

Abstract

Several out-of-spec coals have been studied with respect to their ash behaviour in relation to ash deposition problems in pulverized coal-fired boilers. The coals have been analysed in detail and show increased concentrations of Ca, Fe, Mg, Na or K. Experimental deposition tests with single coals and blends have been performed in a lab-scale facility and in a semi-industrial scale furnace. The results have been evaluated especially with respect to interactions between inorganic species from different coals. Observed mechanisms for the formation of sticky ash particles, responsible for the initiation of ash deposition, are used to derive blending guidelines for the coals.