Effects on Design and Operation of Coal-Fired Utility Boilers with Changes of Coal Qualities

In recent years, with the development of economic, large-scale coal-fired utility power plants got a rapid development in China. The related utility boilers displays on the new characteristics of large-scale capacity, high parameters, varieties and auto-control in high degree. Nowadays, the situation for the transportation and supply of coal for power plants is still in tense. The actual coal qualities differ much from the design value, which will bring the challenges toward the design, operation and management of the units, together with the decrease of the safe reliability and economic performance. Considered the effects on design and operation of large-scale coal-fired utility boilers with changes of coal qualities, the effects of the different typical coals and the blended coals on combustion characteristics including the ignition, slagging characteristics and tendency were investigated in this paper, especially including the changes of the moisture, volatile, sulfur and ash content. At last, the comprehensive strategies towards the brought effects from the changes of coal qualities were presented, together with the relevant advice and solution.