Biochar Needs for the Iron and Steel Industry

As awareness of climate change and global warming grows, along with the Paris Agreement and Net Zero Emissions (NZE) 2050 targets for decarbonization, the use of biomass to produce biocarbon products is increasing. The iron and steel industry, in particular, faces significant demand, while supply remains limited. This has prompted several large companies to invest in large-scale biocarbon production, particularly biochar/biocoke.

Such large-scale production naturally requires abundant biomass feedstock. Specifically, in Indonesia, biocoke/biochar production from palm kernel shells (PKS) reportedly began last year. PKS was chosen because it is a readily available biomass waste product from palm oil mills. PKS and palm oil mill production in Indonesia is estimated to be around 12.5 million tons/year, but because some of the PKS is used as boiler fuel, the estimated usable PKS or remaining boiler fuel is around 6.25 million tons/year. To increase the supply of PKS from palm oil mills, cogeneration of empty fruit bunches (EFB) can be used. For more details, read here.

In addition to the PKS, biocoke/biochar and even black pellets (torrified pellets) are also produced using wood from energy plantations. Energy plantations with short-rotating crops like calliandra and gliricidia have great potential to produce this wood. Currently, wood pellets (white pellets) are being produced from these wood plantations. For more details on whether wood from energy plantations is better for wood pellets (white pellets) or biocoke/biochar/charcoal, read here.

Biocoke, biochar, and charcoal are used in the iron and steel industry as a substitute for coal-based coke in blast furnaces, while wood pellets (white pellets) and torrified pellets (black pellets) are used in power plants using both cofiring and fulfiring. In addition to their higher calorific value (around 20% higher than wood pellets (white pellets)), torrefied pellets (black pellets) are also hydrophobic, allowing them to be stored outdoors, like coal.

In today's era, the use of biocoke / biochar / charcoal to replace coal coke in blast furnaces is becoming important. Biocoke / biochar / charcoal derived from biomass is a renewable material that is sustainable as a reducing agent or fuel in blast furnaces. The chemical reaction will separate oxygen atoms from iron atoms and this will emit CO2. This will convert iron ore (Fe2O3) into crude (pig) iron.

However, the difference lies in the fact that the carbon source used as a reducing agent or fuel in a blast furnace comes from renewable and sustainable sources, making it a carbon-neutral process. Conversely, using coke from coal, as it comes from a fossil source, makes it a carbon-positive process. Similarly, using natural gas, a fossil fuel, as a carbon source for the reducing agent or fuel in a blast furnace, despite its lower carbon intensity, is considered less carbon intensive. 

Washed PKS for Decarbonization of Iron and Steel Plants

The steel industry contributes 8% of global CO2 emissions, with each ton of steel produced producing an average of 1.85 tons of CO2 emissions. Compared to iron ore mining, iron and steel production contributes significantly more to CO2 emissions. Decarbonization efforts in the steel industry begin with the use of renewable energy for smelting. Biomass-based fuels, such as charcoal, which has a high carbon value, can replace the use of coke derived from coal. The use of hydrogen from renewable energy sources is the ultimate decarbonization target for the steel industry.

Currently, the steel industry largely uses coal as an energy source or reducing agent. This coal is processed into coke and used in blast furnaces. It is estimated that approximately 70% of global steel production uses the blast furnace or BF-BO process, and in China, over 90% of steel production uses the BF-BOF process. To reduce carbon intensity, natural gas is used as the fuel. The use of natural gas as a gaseous fuel also acts as a transition medium and, because it is derived from fossil fuels, is also a carbon-positive fuel.

Nearly all CO2 emissions in the steel production sector come from blast furnaces (BFs), which refine iron ore into crude iron or pig iron. The challenge is significant: there are approximately 1,850 steel mills worldwide, with approximately 1,000 using blast furnaces, producing approximately 1.5 billion tons of pig iron annually.

The use of charcoal in a blast furnace not only reduces carbon dioxide (CO2) emissions but also sulfur dioxide (SO2) emissions due to its very low sulfur content (approximately 100 times lower) than coke. Likewise, the use of limestone is reduced, thereby automatically reducing slag production. This also makes the blast furnace's operation acidic.

The use of biomass-based carbon fuel (biocarbon) in the form of charcoal has a better climate impact because it is carbon-neutral. Furthermore, technically, because it is a solid fuel, similar to coke derived from coal, it requires little or no changes or modifications to the smelting furnace. However, the availability of high-quality charcoal, large volumes, and a continuous supply remain major constraints.

This makes the use of charcoal to replace coal-based coke in blast furnaces crucial. Charcoal, derived from biomass, is a renewable, sustainable material used as a reducing agent or fuel in blast furnaces. The chemical reaction separates oxygen atoms from iron atoms, emitting CO2. This converts iron ore (Fe2O3) into crude (pig) iron.

However, the difference lies in the fact that the carbon source used as a reducing agent or fuel in a blast furnace comes from renewable and sustainable sources, making it a carbon-neutral process. Conversely, using coke from coal, as it comes from a fossil fuel, is a carbon-positive process. Similarly, using natural gas as a carbon source for reducing agents or fuel in a blast furnace, although it is said to have lower carbon intensity, is also considered a carbon-neutral process.

The use of charcoal or biocarbon materials for metallurgy or steelmaking has actually been commonplace for some time. In the early 1900s, global charcoal production reached its peak, exceeding 500,000 tons. In the 1940s, charcoal production declined to nearly half its early 1900s levels due to the replacement of other carbon materials, such as coke from coal, in the manufacture of steel and other metals.

Charcoal is a fuel and reducing agent derived from biomass that has significant potential for use during this transition phase. Palm kernel shells (PKS) are a potential biomass raw material for charcoal production. Palm kernel shells (PKS) are available in the millions of tons, ensuring a reliable supply. Charcoal, a product of biomass carbonization or pyrolysis, has a high calorific value, high fixed carbon content, and stability. However, another factor, ash chemistry, influences the quality of the resulting steel. This is somewhat similar to the ash chemistry of wood pellets from calliandra or gliricidia energy plantations.

When used as a reducing agent in blast furnaces, charcoal must have a low phosphorus content, while wood pellets from calliandra or gliricidia energy plantations must have low potassium, sodium, and chlorine content. The potassium, sodium, and chlorine content of wood pellets affects the quality of the wood pellets and their use in power generation. Pulverized combustion power plants, widely used worldwide, will reject wood pellets with this quality. Similarly, blast furnaces will reject charcoal with a high phosphorus content.

To achieve this quality, low-phosphorus content, the palm kernel shells (PKS) must first be washed. After washing, the phosphorus content decreases, and they are then dried and pyrolyzed, or carbonized, to produce palm kernel shell charcoal (PKSC). The same applies to wood pellets. The only difference is that wood pellet production doesn't involve pyrolysis or carbonization; instead, after drying and achieving the desired particle size, the pellets undergo biomass densification in a pelletizer.

Steel production requires an average of 6,000 MJ of energy per ton (equivalent to 50 kg of hydrogen) or 200 kg of charcoal, and requires approximately 600-800 kg of woody biomass as raw material. With a calorific value nearly identical to woody biomass, this is equivalent to using palm oil mills (PKS), which are plantation or agro-industrial waste.

Meanwhile, demand for low-carbon steel is growing rapidly as steel industries and governments worldwide commit to reducing carbon emissions from fossil fuels. The use of charcoal or biocarbon in blast furnaces is a key component of low-carbon steel production, as 100% of the steel is not yet produced using renewable energy. 

Biochar for Biographite as a Key Component of Electric Vehicle Batteries

The use of fossil fuels makes the transportation sector contribute 24% of global CO2. With CO2 emissions from fossil fuel use estimated to reach 36.3 gigatonnes (36.3 billion metric tons) in 2024, the transportation sector contributes 8.71 gigatonnes (8.71 billion tons) of CO2. Efforts to reduce CO2 emissions from the transportation sector are carried out in two ways: the use of renewable energy and the use of electric vehicles. The use of electric vehicles must be accompanied by the provision of renewable energy sources. Do not just use electric vehicles, but the energy source still comes from fossil fuel sources. Biofuel is a renewable energy source for the transportation sector that can be used directly with minimal vehicle modifications or even without any engine modifications at all. The question of whether to prioritize electric vehicles first or the use of biofuels first can be read in more detail here.

Electric vehicles can indeed be a decarbonization solution in the transportation sector, with the aforementioned considerations. And it would certainly be even better if the production of these electric vehicles also used materials from renewable sources, such as graphite for batteries derived from biochar or components such as chassis, body, and other metal components from "green steel" or "low carbon steel." Regarding graphite from biochar or biographite, with an average of 70 kg per car required, with projections according to the International Energy Agency (IEA) that electric car production by 2030 (including buses, vans, and heavy trucks) reaching 145 million units, the need for biographite will reach more than 10 million tons. In fact, according to the Economist, in that year, graphite demand is expected to exceed supply by 2 million metric tons, thus threatening the steel and battery industries. This means graphite production needs to be increased, but of course, that production will be biographite for better environment aspect, not synthetic graphite derived from fossil fuels. Meanwhile, in Indonesia itself, the government is targeting 2 million electric cars and 13 million electric two-wheeled vehicles by 2030. The use of biographite is intended to replace graphite derived from fossil sources which is still commonly used and with China as the main producer (controlling more than 80% of global (synthetic) graphite production).

Furthermore, Indonesia is rich in nickel, with reserves reaching approximately 5.3 billion tons of ore, equivalent to approximately 55 million metric tons of nickel metal (East Asia Forum, 2024), and holds the world's largest reserves. Australia ranks second with approximately 24 million metric tons of nickel metal, while global nickel reserves are estimated at approximately 130 million metric tons. This should place Indonesia in a strategic position in the era of electric vehicle use. In 2023, Indonesia produced approximately 1.8 million metric tons of nickel, accounting for nearly half of total global production (Statista, 2023). Nickel helps increase the energy density and storage capacity of batteries, enabling electric cars to have a longer range. Each electric car battery is estimated to use 30 kg of nickel. With the International Energy Agency (IEA) projecting electric car production by 2030 to reach 145 million units, the need for nickel will reach nearly 4.5 million tons.

In addition to properly managed nickel mining for environmental sustainability, the country's natural resources, particularly nickel, should also be processed into finished products domestically. Exporting semi-finished products or even raw materials, which offer little added value and are less profitable, should be avoided. Furthermore, if all nickel were exported to China, the world's largest graphite producer, it would make China a major global producer of electric car batteries. With biographite production, Indonesia would become less dependent on imports, and downstream nickel processing would make its own electric battery production highly feasible, potentially even becoming a major player in the battery industry. Nickel is also used in the production of stainless steel, a widely used material. 

Biochar and Biographite for Decarbonization in the Iron and Steel Industry

The decarbonization trend continues across all sectors, particularly strategic industries such as the energy industry, iron and steel industry, and transportation. These industries contribute significantly to CO2 emissions, which increase atmospheric concentrations (carbon positive). The energy industry, particularly power generation, contributes 27.45%, the steel industry 8%, and the transportation sector 24%. With an estimated total CO2 emissions from fossil fuels of 36.3 gigatonnes (36.3 billion metric tons) in 2024, the iron and steel industry's contribution is approximately 2.9 gigatonnes (2.9 billion metric tons).

In the steel industry, carbon neutral production will be achieved when iron and steel production in the industry uses 100% renewable energy. The use of electric arc furnaces (EAFs) can be done as long as the electricity is generated from renewable energy sources. However, the use of EAFs that still use electricity from fossil fuels can be a transition medium before 100% carbon neutral production because of its lower CO2 emissions compared to blast furnaces that use coke from coal. CO2 emissions from blast furnaces are around 2.33 tons for each ton of crude iron / pig iron, while with EAFs, they are only around 0.66 tons for each ton of crude steel. The raw material processed with EAFs is steel scrap, and approximately 80% of steel scrap is currently recycled with EAFs. Globally, steel production with EAFs reaches approximately 22%.

And the fact is that currently, to achieve this goal is still far because the construction of blast furnaces - basic oxygen furnaces (BF -BOF) is still being carried out a lot, which should be EAF (Electric Arc Furnace) or currently only about 30% of the global iron and steel industry uses this EAF. The construction of new blast furnaces is indeed tending to increase, in fact, by mid-2024, around 207 million tons per year of new production has been announced and around 100 million tons per year is under construction.

Nearly all CO2 emissions in the steel production sector come from blast furnaces (BF) for refining iron ore into crude iron or pig iron. The challenge is enormous: there are approximately 1,850 steel mills worldwide, with approximately 1,000 using blast furnaces, with pig iron production reaching approximately 1.5 billion tons per year. The International Energy Association (IEA) has even highlighted this critical issue in achieving the Paris Agreement's net-zero target by 2050. With an average blast furnace lifespan of 20 years, the iron and steel industry's efforts to achieve this target must be well-formulated and programmed. Failure to replace blast furnaces within the specified timeframe will jeopardize the 2050 net-zero emissions target.

This makes the use of charcoal to replace coal-based coke in blast furnaces crucial. Charcoal derived from biomass is a renewable, sustainable material used as a reducing agent or fuel in blast furnaces. The chemical reaction separates oxygen atoms from iron atoms, releasing CO2. This converts iron ore (Fe2O3) into crude (pig) iron. The difference is that because the carbon source as a reducing agent or fuel in blast furnaces comes from renewable and sustainable sources, this process is carbon neutral. Using coke from coal, which comes from fossil fuels, is carbon positive. Similarly, using natural gas as a reducing agent or fuel in blast furnaces, despite its lower carbon intensity, is still carbon positive. 

However, if hydrogen from renewable energy sources (green hydrogen) is used as a reductant in the blast furnace, it will not produce carbon emissions but will produce water vapor (H2O), thus it is also a carbon neutral process. However, this will still take a long time, predicted to take several decades to implement. To produce a carbon negative process, the iron and steel mills that are already operating carbon neutrally must be equipped with CCS (Carbon Capture and Storage) devices, which will certainly be the next step. Furthermore, the use of renewable energy as an EAF energy source is also becoming increasingly important and must be accelerated, which should also be in line with the use of bio-graphite in the EAF.

The use of EAF in iron and steel mills is estimated to reach 550 units worldwide with steel production reaching around 548 million tons or around 30% of the world's steel production which will reach around 1.8 billion tons in 2024. The use of EAF requires graphite electrodes and every ton of steel produced requires an average of 3 kg of graphite. The current source of graphite is almost all derived from fossil sources so it is a source of carbon emissions (carbon positive) and also currently around 80% of the world's graphite supply comes from China. With steel production from EAF of 548 million tons, the annual graphite demand reaches more than 1.6 million tons. Every ton of graphite production from fossil materials emits CO2 emissions of 17-40 tons.

This makes the use of biographite crucial because it is carbon-neutral, producing CO2 emissions. Biographite is produced from biochar, or charcoal, which undergoes a special purification process. The biochar is converted into high-purity graphite suitable for EAF electrodes. Biographite is used for its strength, density, and conductivity, not only because of the CO2 emissions mentioned above, but also because of its technical advantages. Naturally mined graphite cannot meet these technical specifications, while synthetic graphite from fossil fuels is not environmentally friendly and is highly dependent on imports. This is the driving force behind biographite production.

The demand for biochar or charcoal as a reducing agent in BF will be very large, while for biographite as an EAF electrode is not as large as in BF. This makes it crucial to obtain a source of biomass raw materials as a source of biochar or charcoal in sufficient volume, good quality, and sustainable. Similarly, in terms of biochar or charcoal production, which primarily uses pyrolysis/carbonization technology, it must also be able to produce products with adequate quality and quantity, sustainably, and with a production process that is high in productivity, efficient, and environmentally friendly. Biochar or charcoal with specifications of at least 85% fixed carbon and a minimum conversion (gravimetric yield) of 30% is the reference for selecting this pyrolysis technology. 

In addition to biomass waste groups such as forestry waste and plantation waste, energy plantations can also be specifically created for this purpose, for more details read here. These energy plantations must also be created according to the land allocation and area of ​​monoculture energy plantations in accordance with proper planning and procedures, as well as efficient and environmentally friendly pyrolysis / carbonization technology. Biomass sources as raw materials for charcoal / biochar can also be said to be sustainable if the harvested product is less or at most equal to the growth of the plantation's wood. This is to prevent what happened in Brazil, namely in the state of Minas Gerais. Due to the large area of ​​monoculture eucalyptus plantations whose wood products are mostly for charcoal production for iron and steel mills, this has caused various negative impacts on the environment. Brazil is the world's largest charcoal producer and produced 5.2 million tons in 2017, 90% of which was used by the iron and steel industry, with 80% of the charcoal produced from eucalyptus plantation wood.

Approximately 70% of Brazil's iron and steel production occurs in the state of Minas Gerais, and this sector is unique in that 34% of iron production uses charcoal, not mineral coke/coal, and coke is also widely used in steel production. Historically, this was due to a lack of mineral coke in Brazil, but abundant forests for coke production. Minas Gerais currently has nine steel mills and 41 iron plants producing 3.1 million tons of crude iron in 2018, approximately 50% of which was exported. In 2018, Brazil had 5.7 million hectares of eucalyptus plantations, and Minas Gerais continues to have the largest plantation area in the country, covering 24% (1.4 million hectares) of Brazil's eucalyptus. Iron and steel companies also have eucalyptus plantations in an effort to secure a supply of charcoak for their iron and steel mills. Indonesia also has vast land potential, reaching hundreds of millions of hectares for these energy plantations. 

Decarbonization of the Iron and Steel Industry Part 3: from Low Carbon Production to Carbon Neutral Production

When the decarbonization target must be achieved according to the specified deadline, various efforts will also be made, including through a transition phase. The transition phase in the iron and steel industry is from low carbon production to neutral carbon production. There are a number of factors that influence towards this goal, especially the readiness of the market to buy iron and steel products produced from the production process and also the readiness of fuel and reducing agents for blast furnaces in the iron and steel industry. Charcoal is a fuel and reducing agent derived from biomass which has great potential for use in this transition phase. Charcoal as a carbonization or biomass pyrolysis product has a high calorific value, high fixed carbon and is stable.

Meanwhile, carbon neutral production conditions will be achieved when iron and steel production in the industry uses 100% renewable energy. The use of an electric furnace (EAF/Electric Arc Furnace) can be done as long as the electricity is produced from renewable energy sources. Likewise, the use of hydrogen fuel in blast furnaces (with electrical energy for plant operations also from renewable energy) is also able to achieve carbon neutral production conditions, and even the use of hydrogen fuel in blast furnaces is considered to be the ultimate goal in decarbonization of the iron and steel industry. With the target of achieving net zero emissions by 2050 and the average service life of blast furnaces being 20 years, the iron and steel industry's efforts to achieve the target must be well formulated and programmed. Even if efforts to replace blast furnaces do not follow this target time, it will put the achievement of net zero emissions by 2050 in jeopardy.

In fact, currently it is still far from achieving this goal because the construction of blast furnaces - basic oxygen furnaces (BF -BOF) is still being carried out, which should be EAF (Electric Arc Furnace) or currently only around 30% of the global iron and steel industry uses this EAF. Even the International Energy Association (IEA) highlighted this critical issue to achieve the Paris Agreement's net-zero target by 2050. CO2 intensity in this industry has only slightly decreased so that the use of renewable energy becomes increasingly important and accelerated.

A case example is the Japanese iron and steel industry. As a steel producer of more than 85 million tons per year with main use in domestic construction projects and automotive manufacturing and with more than 25% (more than 21 million tons) being exported, the Japanese steel industry has a significant influence on the global market. The dominant dependence on coal is the main problem of decarbonization and moreover, Japan is also the third largest coal importer in the world. Furthermore, decarbonization in Japan is considered inadequate because the Japanese steel industry lags behind other major world steel producers. Japan is a G7 country that does not implement a coal phaseout period.

Nippon Steel has even been labeled a climate laggard or slow to respond to the climate crisis in the Asian region. This is because the decarbonization strategy is inadequate or not in accordance with the IPCC's 1.5°C warming pathway or the IEA's net-zero pathways. This condition threatens national and global decarbonization targets and puts Japan's steel industry at risk. Meanwhile demand for low-carbon steel is increasing rapidly because steel industries and governments around the world are committed to reducing carbon emissions from fossil fuels. The Japanese steel industry needs to immediately decarbonize to remain competitive in the global market. Decarbonizing by investing in low-carbon steel production will address these risks and can position the Japanese steel industry as a leader in the green transition of the global steel industry.

 

Regarding the issue of fuel or renewable energy sources, biomass has a strategic position and role, namely in blast furnace operations, charcoal, which is a product of biomass carbonization, is used as a fuel and reducing agent, while in electricity production for iron and steel plant operations, biomass can be used as a renewable energy sources or biomass power plants. This is why the availability of biomass is very important so that the creation of energy plantations as a source of biomass is very necessary. Not only is the plantation a source of energy, it can also play a role in the production of food and feed, both of which are very beneficial for human life. And of course optimizing the use of the plantation by utilizing all parts of the tree (whole tree utilization) also provides maximum financial / economic benefits and with good management it will also provide benefits or improve the environment. And ideally by 2050 the steel industries will use electric arc furnaces / EAF, 100% hydrogen in blast furnaces and even a combination of carbon capture, to achieve net zero emissions in 2050 or even negative emissions so it is very good for the climate.