Coal in a Sustainable Society

This report builds on an earlier ACARP project C8049 Environmental Credentials of Coal and is aimed at assisting the coal industry to understand the role of coal in a sustainable society, for both iron and steel production, and for electricity generation.

This project consists of a number of components:

• LCA case studies of an expanded range of emerging steelmaking technologies with a particular focus on those which are coal based - technology evaluations are also included for a number of the coal based processes.
• LCA case studies on a range of electricity generation technologies, with a wider range of renewable technologies and sequestration options in an Australian context. LCA case studies for included for cement production, coal mine operation, coal mine waste utilisation and fly ash utilisation. These case studies provide the basis for allocation of displacement credits for selected by-products from steel production and electricity generation.
• Experimental studies to determine the properties of coal related to emerging iron making technologies.
• Techno-economics of the major emerging coal based technologies for iron and steel production, compared with conventional processes.

The key findings from this report are given below.

The iron and steel LCA case studies show that, in terms of resource energy and greenhouse gas emissions (GGEs), the emerging coal based technologies compare favourably with gas based routes, if displacement credits can be claimed.

There is clearly a change emerging in technologies for iron and steel production which favours the use of coal (eg composite pellets in rotary hearth furnaces, mini and compact blast furnaces, non recovery coke ovens), and the coupling of hot metal production to electric arc furnaces. The "dash to gas" is slowing. An important issue for the Australian coal industry is the relationship between coal properties and operating performance for these emerging technologies.

A substantial number of electricity LCA case studies (19) have been carried out for a wide range of technologies. A number of opportunities have been identified from these studies for reducing the GGEs for coal based electricity generation technologies.

LCAs were also carried out on cement production, coal production, and coal mine waste and fly ash utilisation.
The GGE results for cement compared favourably with those published by the IEA (approximately 1 t CO2-e/t of cement clinker); when allowance was made for fly ash and blast furnace slag use in Australian cements, the results were in agreement with those published by the Cement Industry Federation.

Extensive overseas discussions (September-October 2000) confirmed that coal's positive attributes (cost, wide availability, ease of transportation and storage, and energy density) will underpin the transition to more sustainable energy systems. It is therefore important to reverse the decline in coal R&D which has occurred in many developed countries, and to transfer technology (eg through CDM) to developing countries, and in particular China and India.