Energy Center - CCTR

Enhancing Coke Production Energy Efficiency While Reducing Emissions

Introduction:
A viable supply of iron is one mainstay of economies throughout the world. Issues associated with the supply and price of iron, which is used to produce steel, play either a direct or indirect role in all modern business operations. There is currently enormous incentive to assure the supply, quality, and price of raw materials used in iron production and that these raw materials are produced in an environmentally friendly manner. One of the major components used in the iron making process is coke. Coke is a solid carbon fuel and carbon source produced from coal that is used to melt and reduce iron ore. Although coke is an absolutely essential part of iron making and foundry processes, currently there is a shortfall of 5.5 million tons of coke per year in the United States. This shortfall has resulted in increased imports and drastic increases in coke prices and market volatility. In addition, historically there have been concerns with emissions from traditional coke production facilities.

A new approach to coke production is being developed involving the continual optimization of the process in concert with the production of other value streams based upon market price and availability. The developed process leverages non recovery/heat recovery coke production methods by using pyrolysis gas extracted at specific operating temperatures and conditions. This optimizes high value product production and minimizes by-product emissions in comparison with more conventional techniques. Using the developed technology, it is estimated that such a Multi-Purpose Coke Facility would use up to 40% low rank coal and thereby significantly reduce coal costs and at the same time environmental emissions. By producing multiple value streams as part of the coke production process, it will be possible to increase economic value of the process and simultaneously reduce the impact of price fluctuations in the coke market.

The market price of coke has varied from $130 to $800/ton since 2009. Such fluctuations have caused considerable production planning issues. The current research, through the use of optimized multiple value streams, can reduce the effects of this market volatility by providing alternative revenue streams from multiple products including coke, fertilizer, electricity, Fischer-Tropsch transportation fuels, and hydrogen. It also helps to produce jobs and a new market for lower rank coal. By utilizing pyrolysis gas to produce multiple high value products in conjunction with coke production it is possible to leverage value of the coke oven investment. Recent circumstances in the coke market have placed enormous strain on the steel industries. The developed process can provide at least a partial resolution and/or mitigation of this formidable problem through the use of a blend of low rank and conventional coal in a mine mouth or local, environmentally friendly, high efficiency coking/coal gasification facility which would increase coke supply and production, while, at the same time, reducing the cost for the steel and foundry industry.