Pulverized coal injection method: Difference between revisions

Revision as of 22:02, 14 December 2011

Revision as of 05:39, 10 August 2012

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Pulverized coal injection was developed in 19th century, but was not implemented industrially until the 1970s. Rises in the cost of [[coke (fuel)|coke]] cost due to increased global demand and thus more competition for the resource have made this method attractive to the iron producing industries and increased its value.

The PCI method is based on the simple concept of primary air (termed the "conveying gas") carrying pulverized coal which injected through a lance to the [[tuyere]] (mid-bottom inlet of a blast furnace), then mixed with secondary hot air (termed the "blast") supplied through a blowpipe in the tuyere and then piped to a furnace to create a balloon-like cavity called a "raceway", which then propagates coal and coke combustion and melts the solid iron ore, releasing molten iron. The most remarkable aspect of this method is that it allows for cheaper coal to be consumed in the system, replace expensive coke, thereby remarkably cutingcutting down on costs. Because of the severe environment inside the furnace, (>2000K), visual observation of raceway shape and size is impossible, therefore remotely measuring sensors are used to investigate the chemical and physical reactions inside the furnace.

Better understanding of the raceway and PCI method can optimize the performance of a blast furnace and reduce costs. Further improvements to the PCI method and the use of coal blend (mixing different coals) injection methods are attracting industry.