Pulverized Coal Injection

Pulverized Coal Injection (PCI) is a process that involves blowing large volumes of fine coal granules into the BF. This provides a supplemental carbon source to speed up the production of metallic iron, reducing the need for coke production.  As a result energy use and emissions can be reduced.   However, as coke provides physical support and gas permeability in the BF, its complete substitutions is not possible. The amount of coal that can be injected will depend on the coal and coke quality, furnace geometry, and operational practices.  The maximum level of coal that can be injected at the tuyére is around 0.27 t/t-Hot Metal(HM). The use of oxy-coal enables around 20% increase in coal injection and help reduce coke quantities accordingly (Worrell et al., 2010).

With 170 - 200 kg/t-HM pulverized coal injection, coke consumptions as low as 286 - 320 kg/t-HM has been achieved in modern blast furnaces.  However, global average for PCI remained at 125 kg/t-HM in 2005 (IEA, 2007. p. 117). Although PCI increases the costs for extra oxygen supply, BF maintenance, and coal grinding, these are offset by reduce coke production/purchase costs making providing an overall reduction in operation and maintenance costs.  Cost of PCI plant largely depends of the size of blast furnace and the layout of the plant. The layout of the plant can make it difficult to install PCI accessories with some alternative arrangements which would ultimately increase the installations costs.

Chinese flag Indian flag US flag While this technology is regarded to have a high potential for application in China and India, in the case of US, injectin of natural gas may be a more cost effective measure. 

Development Status Products
Commercial
iron, steel

Pulverized Coal Injection Costs & Benefits

Parent Process: Blast Furnace System
Energy Savings Potential

For every ton of coal injected, 0.85 to 0.95 ton of coke production can be avoided. Energy savings are estimated to be 3.76GJ/t-injected coal. (Worrell et al., 2010, pp. 83-84)

CO2 Emission Reduction Potential

If the average pulverized coal injection rate at global level was 180 kg /t-hot metal, about 10 Mt CO2 could be saved.

Costs

Cost savings in the range of US $16 to 33/t-hot metal can be expected, lowering the hot metal production costs by approximately 4.6%. 

Investment of coal grinding equipment is estimated at $50-55/t Coal injected.

Pulverized Coal Injection Schematic

Pulverized Coal Injection Publications

Energy Efficiency Improvement and Cost Saving Opportunities for the U.S. Iron and Steel Industry

The U.S. Environmental Protection Agency’s (EPA) energy guide, Energy Efficiency Improvement and Cost Saving Opportunities for the U.S. Iron and Steel Industry, discusses energy efficiency practices and technologies that can be implemented in iron and steel manufacturing plants. This guide provides current real world examples of iron and steel plants saving energy and reducing cost and carbon dioxide emissions.

Page Number: 

83

The State–of-the-Art Clean Technologies (SOACT) for Steelmaking Handbook

 

The State–of-the-Art Clean Technologies (SOACT) for Steelmaking Handbook is developed as part of the Asia-Pacific Partnership on Clean Development and Climate program and seeks to catalog the best available technologies and practices to save energy and reduce environmental impacts in the steel industry. Its purpose is to share information about commercialized or emerging technologies and practices that are currently available to increase energy efficiency and environmental performance. 

Page Number: 

41

Page Number: 

117

Pulverized Coal Injection Resources