[ TECHNOLOGY ] produced in such mills report around 1.3 .
Accordingly , from a global perspective the prime focus to achieve decarbonisation should be on the ironmaking step as this is where most of the CO 2 emissions are generated . If the blast furnace smelting route is replaced by direct reduction producing sponge iron ( Direct Reduced Iron - DRI ), the carbon footprint would drop from 2.3 to 1.6 when using natural gas as reductant . Naturally , increased production of DRI is suggested as a solution , particularly as it could be using clean hydrogen as reductant if it is available at required scale and cost . DRI production is well established , and steadily increasing over time .
The world steel production is close to 1,900 million tonnes
Joachim von Schéele , Global Director Commercialization , Linde
( Mt ) annually , with a supply of iron for that steelmaking being around 1,300 Mt of hot metal from blast furnaces . The world DRI production exceeds 130 million Mt with more than 90 Mt using natural gas as reductant , the balance using coal and almost all that in India . Additionally , about 800 Mt of scrap are charged .
Today ’ s DRI production
The Swedish Professor Martin Wiberg ( 1894-1975 ) was the
Pravin C . Mathur , Executive Director , Linde
father of modern shaft-based Direct Reduction processes , later to be developed into well-known processes such as Midrex ( 1969 ), HyL ( 1957 / 1980 ), etc . Wiberg and coworkers started pilot scale tests at Voxna Bruk in 1920 . Later followed full-scale operations at many other Swedish locations : Söderfors ( 1933-1961 ) at 10 kt / a ; Sandviken ( 1952-1980 ) at 20 kt / a ; Hällefors ( 1953-1963 ) at 20 kt / a ; Persberg ( 1953-1973 ) at 40 kt / a ; and Hofors ( 1955-1978 ) at 30 kt / a .
Decarbonisation Solutions for Ironmaking CCS , H 2
, and Low Carbon Fuels are Primary Solutions
CCS
H 2
Low C Fuel
H 2
H 2 Injection
Max 15 kg / t 10-15 % decarb
Blast Furnace
Co 2 Capture
Power Plant Stoves
Blast Furnace Gas iron ore , limestone , and coke molten iron
Co 2 Capture
CO 2
CO 2 blast furnace
hot air
slag
Blast Furnace
Co 2 Storage
Co 2 Utilization
CO , H 2 Recycle
Flue Gas
NG
DRI Plant
Co 2 Storage
Co 2 Removal
Reducing Gas CO + H 2
Preheat
Top Gas
H 2 H 2 Injection Max 54-70 kg / t 100 % Decarb
H 2 can be blended in steps - for example , 30 %, 70 %, 100 %
Co 2 Utilization
DRI
Green Steel World | Issue 10 | February 2024 27