Pulverized coal injection method: Difference between revisions

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The blast furnace method is expected to survive into the 22nd century because of its efficient rate of iron production at competitive costs compared with other iron making methods. Blast furnaces keep on improving with adaptations arising from new technologies driven by rising global demand, yet the main chemical process remains same. But process improvement cannot solve many of the problems associated with blast furnaces. The rate of iron production is highly influenced by fluctuations in the world economy, and improving the operational efficiency of the process is of major concern. However, the biggest drawback of blast furnace operation is the inevitable [[carbon dioxide]] production from iron reduction processes, which is considered one of the major contributors in [[global warming]]. Accordingly, the Pulverized Coal Injection (PCI) method is becoming an internationally popular method for improving blast furnace operation.

==Pulverized Coalcoal Injectioninjection method==

Pulverized coal injection was developed in 19th century, but was not implemented industrially until the 1970s. Rises in the cost of [[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 beingwhich 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 cuting down on costs. Because of tehthe 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.