ArcelorMittal Indiana Harbor, the largest steel mill in North America, is recycling blast furnace gas to produce high-pressure steam used to power its steel mill.
Yesterday, the 504-boiler project was officially commissioned.
ArcelorMittal Indiana Harbor is home to no. 7 blast furnace, the largest blast furnace in the United States. Approximately 78 percent of the blast furnace gas that is generated is used for heating stoves at no. 7 and for making steam at no. 5 boiler house. Until recently, the remaining 22 percent, or 46 bn cubic feet, of blast furnace gas per year was wasted when it was flared into the atmosphere.
The $63.2 million 504-boiler project involved constructing a new water system and modifications to the no. 5 boiler house to add a high efficiency, energy recovery BFG-fired boiler. The system transfers blast furnace gas from a flare at no. 7 to the new boiler capable of generating steam and electricity. The new boiler is located adjacent to and interconnected with the existing no. 5 boiler house. Existing equipment at no. 5 boiler house continues to operate as it has for many years, while the new boiler provides additional capacity to consume blast furnace gas and generate steam.
The new boiler system:
- Generates 350,000 lbs. of steam per hour
- Generates 333,000 MWh of power a year, which is equivalent to the electricity needs of about 30,000 homes
- Reduces CO2 emissions by 340,000 tons a year
- Saves the facility nearly $20 million in energy costs, which has the effect of lowering the production costs of steel by $5 per ton
The project was funded with a matching grant of $31.6 million from the US Department of Energy, under the American Recovery and Reinvestment Act. With support from the DOE grant, along with 50 percent from capital investments of ArcelorMittal, the return on investment is 29 percent and simple payback – the amount of time it will take to recover the initial investment – is 1.58 years.