Decarbonization in the Steel Industry

World steel production reached 1.9 billion tons in 2020, with China accounting for around half and followed by European Union countries. Germany, with annual production of around 42 million tonnes, is the largest steel producer in Europe or around a quarter of European steel production, while the other quarter is Italy and France, followed by Belgium, Poland and Spain. The steel industry contributes 8% of CO2 globally, each ton of steel production produces an average of 1.85 tons of CO2 emissions and compared to iron ore mining, iron and steel production contributes much more to CO2 emissions. Efforts to decarbonize the steel industry begin with the use of renewable energy for its smelters. Biomass-based fuel in the form of charcoal which has a high carbon value can replace the use of coke derived from coal. And the use of hydrogen from renewable energy sources is the ultimate target for decarbonization in the steel industry. 

Currently, the steel industry mostly uses coal as fuel using blast furnaces. To reduce carbon intensity, natural gas is used as fuel. The use of gas fuel in the form of natural gas is also a transition medium and basically because it comes from fossil fuels it is also a carbon positive fuel. Apart from that, the use of CNG in the form of natural gas is also a transition fuel before switching to hydrogen from renewable energy. The use of biomass-based carbon fuel in the form of charcoal has a better effect on the climate because it is a carbon neutral fuel. Apart from that, technically, because it is a solid fuel, the same as coal, practically there is not much or even no need for changes or modifications to the smelting furnace. The availability of high quality charcoal, large volumes and continuous supply are still the main obstacles.

The use of charcoal for metallurgy or steel making has actually become commonplace for some time. In the early 1900s, world charcoal production experienced its heyday with production of more than 500 thousand tons. In the 1940s, charcoal production decreased to almost half of what it was in the early 1900s, due to other carbon materials, namely coke from coal, replacing charcoal in the manufacture of metals.

With the current conditions of using coal as the main fuel in smelting furnaces or blast furnaces, slag will be produced. Slag or GGBFS (Grounded Granulated Blast Furnace Slag) from the steel plant is used in cement plants as a cement additive or SCM (supplementary cementious material) thereby reducing the portion of clinker in cement production. In the cement plant itself, the more slag or SCM used, the more clinker use is reduced, thereby also reducing CO2 emissions. In cement production, the clinker production section contributes the most to the CO2 emissions produced, so the use of slag or SCM is part of decarbonization in cement plants. It is estimated that around 70% of world steel production uses the blast furnace or BF-BOF process which produces quite a lot of GGBFS, even in China more than 90% of steel production uses the BF-BOF process. It is worth noting that the decarbonization of the steel sector is resulting in a shift away from blast furnaces, which will impact the availability of GGBFS worldwide in the coming decade. However, this change will occur slowly and gradually and, in the meantime, there are a number of GGBFS that will be available for use as SCM to reduce the carbon footprint of cement and concrete.

To be able to produce charcoal in large quantities, raw materials are also needed in large quantities. Raw materials in the form of biomass, especially wood, can be produced from energy plantations. Energy plantations from fast growing species and short rotation crops will be suitable to meet the need for raw materials because apart from the fast harvest period they also have high productivity. Apart from that, there is no need to replant every time it is harvested and it is easy to grow and easy to maintain. To produce steel per ton, an average of 6,000 MJ of energy is required (equivalent to 50 kg of hydrogen) or the equivalent of 200 kg of charcoal and requires around 600-800 kg of wood biomass as raw material. Apart from raw materials from energy plantation wood, raw materials from agricultural and plantation wastes can also be used.

The future palm oil industry could produce hydrogen from biogas. Each ton of steel will require 50 kg of hydrogen, while each palm oil mill with a capacity of 30 ffb/hour can produce 1 MWh of electricity, while the production of 1 kg of hydrogen requires 50 KWh, so that with the capacity of the palm oil mill it can produce 20 kg of hydrogen. Areas with a high concentration of palm oil mills such as Riau province could create a hydrogen pipeline network for environmentally friendly steel mills.

With higher prices for steel produced with renewable energy (green steel), market share is also limited. Currently, only certain uses, such as automotive, buy such premium or green steel. Decarbonization efforts in steel industries can also be carried out in stages, along with the development of renewable energy. With the increasing supply of renewable energy, the price will decrease so that environmentally friendly steel (green steel) will also become more competitive in price. New steel industries can be built close to these cheap renewable energy sources so that green steel production can become competitive.

Future Palm Oil Mill: Producer of CPO, Biochar and Hydrogen at the Same Time

Efficiency factors, optimizing potential and improving climate should be implemented simultaneously in the palm oil industry. This can be done by replacing the combustion furnace in the boiler with pyrolysis so that the boiler fuel is mainly biooil, a pyrolysis by-product, with the main product being biochar and building a biogas unit for hydrogen production as the final product. Biochar will be used as a soil amendment together with fertilizer so that it becomes slow release fertilizer, so that fertilizer use efficiency (NUE: nutrient use efficiency) increases. The use of biochar as carbon sequestration, namely by using it together with fertilizer, will also provide additional income from carbon credits. Acid soil or dry soil will have better fertility with the application of biochar.

Furthermore, liquid waste or POME (palm oil mill effluent) is used as raw material for biogas. With the main component of biogas being methane (CH4), with steam reforming the methane will react with steam at a temperature of 700-1100 C with a nickel catalyst to become hydrogen/H2 and carbon monoxide/CO. To maximize hydrogen H2 production, the resulting carbon monoxide / CO is then subjected to a shift reaction, resulting in hydrogen / H2 and carbon dioxide / CO2 products. The reaction runs at a temperature of 400-500 C or at a lower temperature, namely 200-400 C. At higher temperatures the shift reaction usually uses an iron oxide or chromium catalyst, while at lower temperatures the catalysts usually used are copper, zinc oxide and alumina. , which helps reduce CO concentrations to below 1%.

Chemical Fertilizer Plant, Blue Hydrogen, Blue Ammonia and Ruminant Farms

As a comparison of the sheep population in New Zealand with people population of 3 million, the number of sheep is 5 million, then Australia with people population of 25 million, the total population of cattle is 26 million while Indonesia with people population of 270 million, the total population of sheep is less than 50 million, moreover the cattle population is also confirmed much smaller. This indicates that the ruminant livestock sector is not yet a business or industrial engine for economic growth. Whereas in addition to natural resources that support, the need for meat and fertilizer needs for agriculture is also very large. When the ruminant livestock sector is optimized, apart from being self-sufficient in meat as a source of animal protein, it can even be exported, and it will also promote agriculture because the manure is turned into organic fertilizer. This organic fertilizer has many advantages over chemical fertilizers, including not destroying the physical and chemical properties of the soil, activating soil microbes and providing complete nutrients. When the livestock sector is optimized, it is also very likely that it will replace the use of chemical fertilizers or other languages ​​as well as self-sufficiency in fertilizers so that chemical fertilizer plants close or stop producing. The integration of livestock and agriculture will create food sovereignty, an extraordinary achievement if it can be realized.

To save the chemical fertilizer plants, it can be converted into a plant or energy producer in the form of blue hydrogen or blue ammonia. Natural gas, which is a fossil fuel and is the raw material for chemical fertilizers, is separated from the carbon elements so that hydrogen is obtained. Carbon dioxide (CO2) gas that has been separated from natural gas is then captured and stored (CCS = Carbon Capture and Storage) so that it is not released into the atmosphere. And because the raw material for hydrogen fuel comes from fossil fuels, it is called blue hydrogen, whereas if it comes from renewable materials such as biomass, water and so on, it is called green hydrogen. So it can be said that blue hydrogen is still half fossil because the raw materials are from fossil sources and green hydrogen is already 100% from renewable sources. Hydrogen compounds or hydrogen gas have atomic bonds in the form of two hydrogen elements (H2) as a stable compound in nature, and to increase the energy of hydrogen gas, ammonia (NH3) can be made, namely with three hydrogen bonds. Just like the term blue hydrogen above, when the ammonia comes from fossil fuels it is called blue ammonia and when it comes from renewable materials it is called green ammonia. Japanese companies have even made power plants (generators) that use 100% as fuel, for more details read here.

Efforts to boost the livestock sector by integrating with the agricultural sector is not an easy thing. The factors of market access ability, farming techniques, provision of feed, management and livestock business are a number of things that hinder the realization of the vision of food sovereignty. Especially for innovations so that they can be competitive at the international level. Motivation factors, low willingness, low reading and learning culture, lack of friendship for networking, government alignments with policies for less carrying capacity, and so on also hinder on the other hand. But with abundant natural resources potential and strong will, these obstacles should be overcome, especially ruminant farming, especially sheep and goats, is also highly recommended in Islam so that as a Muslim should be more motivated. There is almost no one when doing any kind of effort, let alone to realize a big idea without a hitch, because that is the sunatullah.