Hot Briquetted Iron (HBI) represents a significant advancement in the utilization of direct reduced iron in steel production. While Direct Reduced Iron (DRI) offers a highly metallized iron product derived from the direct reduction of iron ore [Initial Query]1, its inherent properties, such as its pyrophoric nature and susceptibility to reoxidation, pose considerable challenges in handling, storage, and transportation, often necessitating specialized conditions and posing potential safety hazards [Initial Query].1 Hot Briquetted Iron (HBI) has emerged as an innovative solution to effectively address these limitations. It is defined as a densified form of DRI that undergoes a compaction process at elevated temperatures, typically exceeding 650°C (1202°F), and achieves a density greater than 5,000 kilograms per cubic metre (5.0 g/cm³) [Initial Query].6 This compaction process is crucial as it significantly reduces the material's porosity and surface area, thereby substantially mitigating the risks associated with DRI.8
The adoption of HBI is driven by several key advantages. Its enhanced safety in handling and transportation stems from its resistance to self-heating and reoxidation [Initial Query].3 Storage is also simplified, often requiring only open stockpiles with surface ventilation [Initial Query].3 Furthermore, its physical characteristics, including a high density (typically 5.0 to 5.5 g/cm³) and a uniform size and shape, make it exceptionally well-suited for continuous and consistent feeding into steelmaking furnaces [Initial Query].4 The growing importance of HBI in the global steel market is further propelled by the increasing demand for high-quality steel, particularly in electric arc furnace (EAF) steelmaking, and the industry's broader movement towards more environmentally sustainable practices [Initial Query].4 The development and increasing use of HBI highlight a significant step forward in making direct reduced iron a more practical, safe, and efficient raw material for steel production. This transformation underscores the steel industry's commitment to innovation and improvement across its value chain.
Hot Briquetted Iron (HBI) can be comprehensively defined as a premium form of Direct Reduced Iron (DRI) that has been subjected to a compaction process at temperatures exceeding 650°C (1202°F), resulting in a material with a density greater than 5,000 kilograms per cubic metre (5.0 g/cm³).6 This high density is a fundamental attribute that significantly enhances its handling, storage, and melting characteristics in steelmaking applications.4 Typically, HBI is produced in the form of pillow-shaped briquettes, exhibiting relatively uniform dimensions. Common sizes include approximately 90 mm x 50 mm x 30 mm 6 or ranges of 100-120 mm in length, 45-55 mm in width, and 30-40 mm in thickness.2 The weight of an individual briquette is often around 0.5 kg.2 This consistency in size and shape offers notable advantages, particularly in ensuring a steady and predictable flow of material into steelmaking furnaces, which is especially beneficial for continuous charging operations [Initial Query].
A key characteristic of HBI is its high iron content, typically falling within the range of 90% to 94% total iron [Initial Query].4 The metallic iron content, representing the reduced form of iron available for steelmaking, is also crucial, often with minimum specifications such as 83.0% 2 or 85.0%.21 The degree of metallization, defined as the ratio of metallic iron to total iron, is typically high in HBI, often exceeding 90% (e.g., minimum 92.0% 2, typical 91% 8). This high level indicates the effectiveness of the direct reduction process. Furthermore, HBI is characterized by low levels of impurities, including sulfur and phosphorus, which are critical for achieving high-quality steel [Initial Query].4 Typical and maximum allowable concentrations for these elements are tightly controlled (e.g., sulfur maximum 0.020% 2, 0.01% 8, 0.02% 21; phosphorus maximum 0.015% 2, 0.07% 21). The carbon content in HBI typically ranges from 0.8% to 1.5% 6, with variations based on the production process and the specific steel grade being targeted (e.g., 1.0-1.29% 2, 0.6% minimum 21). Carbon plays a vital role in steelmaking, acting as a reducing agent and influencing the final metallurgical properties of the steel.6
Direct Reduced Iron (DRI) exists in several forms, each with distinct characteristics and applications. These include Cold DRI (CDRI), Hot DRI (HDRI), and Hot Briquetted Iron (HBI).7 CDRI is cooled after the reduction process to approximately 50°C and is generally used in electric arc furnaces located near the DRI production facility. It often undergoes passivation to prevent reoxidation.23 HDRI, in contrast, is transported at a high temperature (up to 650°C) directly to an adjacent EAF to leverage its sensible heat, thereby enhancing energy efficiency and overall productivity.1 HBI stands out as the preferred form of DRI for the merchant metallics market, which encompasses DRI produced for trade and shipment to various consumers.7 Its significantly higher density compared to CDRI is the key differentiator, as it substantially reduces the rate of reoxidation and minimizes material losses due to breakage during handling and transportation.5 A notable logistical advantage is that, unlike DRI, HBI only requires surface ventilation during transportation, simplifying the shipping requirements.3
The journey of HBI began with the first sustained commercial production achieved by FIOR in Venezuela in the late 1970s.4 Around the same period, a PUROFER plant was also established in Iran.24 However, a significant technological advancement occurred in the mid-1980s with the successful operation of the first MIDREX plant incorporating hot briquetting at Sabah Gas Industries in Malaysia.24 MIDREX technology has since played a pivotal role in refining and popularizing the HBI production process.4 The increasing adoption of HBI over the years can be attributed to several factors. The overall growth in global steel production has naturally led to a greater demand for high-quality iron sources.16 Furthermore, there has been a growing emphasis within the steel industry on adopting cleaner and more environmentally responsible steelmaking practices, where HBI offers distinct advantages over traditional methods and lower-quality scrap materials.16
The production of Hot Briquetted Iron (HBI) involves a two-stage process: first, the direct reduction of iron ore to produce DRI, followed by the hot briquetting of the DRI. Direct reduction is a method of extracting iron from its ore in the solid state at temperatures below the melting point of iron [Initial Query].1 This contrasts with the traditional blast furnace method, which involves melting the iron ore. Direct reduction processes are broadly classified into two categories based on the reducing agent used: gas-based and coal-based.1 Gas-based processes are the more prevalent globally and primarily utilize natural gas, which is converted into a reducing gas mixture of hydrogen (H₂) and carbon monoxide (CO) in a reformer.11 Common gas-based technologies include MIDREX and HYL/Energiron, which typically employ shaft furnaces and are designed to process iron ore in the form of pellets and lump ores.7 In these shaft furnaces, a counter-flow principle is often used, where hot reducing gas ascends through the descending bed of iron ore, maximizing the efficiency of the reduction reaction.26 Coal-based processes, such as FIOR and FINMET, are less common and often use fluidized-bed reactors to process iron ore fines, with pulverized coal acting as the main reducing agent.7
The detailed steps in HBI production begin with the iron ore reduction stage. Iron ore, typically in pellet or lump form for gas-based processes, is fed into the top of the reduction reactor, such as a shaft furnace [Initial Query].26 The reducing gas, produced from natural gas (hydrogen and carbon monoxide) or coal (primarily carbon), is then introduced into the reactor [Initial Query].26 In gas-based shaft furnaces, the hot reducing gas is injected at the bottom and flows upwards, counter to the flow of iron ore, facilitating efficient heat transfer and oxygen removal.26 This chemical reduction process removes oxygen from the iron oxides in the ore, resulting in the formation of highly metallized iron, known as DRI or sponge iron, which remains in a solid, porous state [Initial Query].1
The second stage is hot briquetting. The hot DRI, which exits the reduction reactor at temperatures above 650°C [Initial Query]4, is continuously discharged into a product discharge chamber (PDC).4 This high temperature is maintained to optimize the subsequent briquetting process.4 The hot DRI is then fed into a specialized briquetting machine, which typically consists of two counter-rotating rollers with specifically designed pockets or molds on their surfaces [Initial Query].26 A significant pressing force, often around 120 kN/cm, is applied to compress the hot DRI into the characteristic pillow-shaped briquettes.26 These compressed strands of briquettes are then mechanically separated into individual units [Initial Query].4 Importantly, in most HBI production processes, no binder is required to maintain the integrity of the briquettes; the high temperature and pressure applied during compaction ensure sufficient inter-particle bonding.4 Finally, the hot briquettes are cooled to prevent excessive oxidation upon exposure to air 4 and are then typically stored in outdoor stockpiles, ready for use or transportation.4 Any fine particles (fines) generated during the briquetting and separation stages are often collected and recycled back into the briquetting press to improve overall yield and resource efficiency.26
Several key technologies and processes are employed in HBI production. MIDREX and HYL/Energiron are the most common gas-based shaft furnace processes.7 The MIDREX process is the most widely utilized DRI production technology globally.29 These processes primarily use natural gas as the reducing agent and are designed to handle iron ore pellets and lump ores. FIOR and FINMET are also gas-based but utilize fluidized-bed reactors and are specifically designed to process iron ore fines.7 FIOR was the first commercially successful process for producing HBI.4 Notably, ACT™ (Adjustable Carbon Technology), developed by Midrex, allows for precise control and enhancement of the carbon content in the produced DRI, and consequently in the HBI, up to levels of 4.0%.4 This technology can be implemented in new plants or retrofitted into existing ones, offering steelmakers the ability to obtain HBI with carbon content tailored to their specific metallurgical needs.
The chemical composition of Hot Briquetted Iron (HBI) is characterized by a high total iron content, typically ranging from 90% to 94% [Initial Query].6 Minimum acceptable levels are often specified by consumers, for instance, 90.0% 2 or 91.5%.21 The metallic iron content, which is the reduced and usable form of iron for steelmaking, is also significant, with typical values around 85% 21 and minimum guarantees such as 83.0% 2 or 85.0%.21 The degree of metallization, representing the percentage of metallic iron in the total iron content, is typically high, exceeding 90% (e.g., minimum 92.0% 2, typical 91% 8), indicating the efficiency of the direct reduction process. The carbon content in HBI generally falls between 0.8% and 1.5% 6, but can vary based on the production technology and customer requirements (e.g., 1.0-1.29% 2, 0.6% minimum 21). Carbon plays a vital role in the subsequent steelmaking process, acting as a reducing agent and influencing the final properties of the steel.
HBI is also notable for its low levels of impurities, particularly sulfur and phosphorus, which are crucial for producing high-quality steel [Initial Query].4 Maximum limits for these elements are typically tightly controlled, such as sulfur at 0.020% 2, 0.01% 8, or 0.02% 21, and phosphorus at 0.015% 2 or 0.07%.21 These low impurity levels are highly desirable in steelmaking as they contribute to superior steel quality and reduce the need for extensive refining processes. Other minor elements and gangue materials, which are unreduced oxides like SiO₂, Al₂O₃, CaO, MgO, etc., are present in small amounts. While generally unregulated, maximum limits may be specified for certain elements like silicon dioxide (e.g., maximum 4.5% 2) depending on the intended application of the HBI.
Characteristic | Unit | Minimum Value | Maximum Value | Typical Value | Source(s) |
| Total Iron (Fe total) | % | 90.0 | - | 91.0 | 2 |
| Metallic Iron (Fe met) | % | 83.0 | - | 84.87 | 2 |
| Metallization Degree | % | 92.0 | - | 93.26 | 2 |
| Carbon (C) | % | 1.0 | 1.29 | - | 2 |
| Sulfur (S) | % | - | 0.020 | 0.007 | 2 |
| Phosphorus (P) | % | - | 0.015 | 0.009 | 2 |
| Silicon Dioxide (SiO₂) | % | - | 4.5 | 3.74 | 2 |
| Briquette Density | g/cm³ | 5.0 | 5.5 | - | 2 |
The physical properties of HBI are also critical to its performance in steelmaking. Its high density, typically ranging from 5.0 to 5.5 g/cm³ [Initial Query]4, is a direct result of the hot briquetting process. This high density facilitates better penetration through the slag layer in furnaces, leading to faster melting.4 The bulk density, which can range from 2.4 to 2.8 g/cm³ 2, allows for more efficient storage and transportation. HBI briquettes typically have a uniform size and shape, often pillow-like, with dimensions around 90-120 mm in length, 45-55 mm in width, and 30-40 mm in thickness.2 This uniformity is advantageous for automated handling and consistent feeding into furnaces [Initial Query]. Compared to DRI, HBI exhibits low porosity 8, making it less permeable to air and moisture, which contributes to its enhanced resistance to reoxidation and improved stability during storage and transport.8 Furthermore, HBI possesses good thermal and electrical conductivity 4, which promotes more efficient melting in electric arc furnaces by facilitating better arc stability and heat transfer.4
In terms of reactivity, HBI is significantly more resistant to reoxidation than conventional DRI, often by a factor of 100.4 It also absorbs about 75% less water than DRI 4, enhancing its stability during shipping and storage. HBI generates fewer fine particles during handling and transport compared to DRI 4, with specifications often limiting fines content.2 It is easy to handle using standard equipment like magnet lifts and grab cranes.2 While safer to transport than DRI, especially by sea 4, bulk sea shipments require watertight holds.2 Storage necessitates hard, non-combustible surfaces without water accumulation, away from contaminants and heat sources.2 Notably, HBI can heat up and release hydrogen when moistened, potentially creating hazardous conditions 2, and it is classified as a material hazardous in bulk (MHB), Group B under the IMSBC Code.2
The utilization of Hot Briquetted Iron (HBI) in steelmaking offers several distinct advantages, primarily stemming from its unique chemical and physical properties. One of the most significant benefits is the enhanced steel quality achieved due to the low levels of residual elements present in HBI [Initial Query].4 Compared to scrap metal, HBI contains minimal amounts of copper, nickel, chrome, molybdenum, tin, sulfur, and phosphorus. This purity enables steelmakers to produce high-quality steel grades, including special bar quality steels, which require strict control over these residual elements.2 Furthermore, the high purity of HBI allows for the utilization of less costly, lower grades of scrap in the furnace charge by diluting the impurities that these scrap grades may contain.4 The consistent and well-defined chemistry of HBI, typically certified by producers, also aids in maintaining melt consistency, leading to more predictable and reliable steel production.8
In Electric Arc Furnaces (EAFs), HBI provides several operational benefits. Its acts as a diluent, effectively reducing the overall concentration of residual elements introduced by scrap in the charge [Initial Query].4 HBI's uniform size and shape allow for continuous feeding into the EAF, which maximizes power-on time, increases the bath weight in the furnace, and ultimately leads to improved productivity [Initial Query].4 The use of HBI also promotes the formation of foamy slag, a crucial aspect of efficient EAF operation. Foamy slag enhances heat transfer from the electric arc to the molten steel, reduces energy losses, and helps to lower nitrogen pickup in the steel, contributing to better quality [Initial Query].4 Additionally, HBI helps in shielding the refractory lining of the furnace from the intense heat of the arc, thereby reducing damage and extending the furnace's lifespan.4 The high density of HBI facilitates its rapid penetration through the slag layer in the furnace 4, and its increased thermal and electrical conductivity contribute to faster melting rates.4 Finally, HBI can act as a nitrogen scavenger in the EAF, resulting in a lower nitrogen content in the final steel product.8
While primarily utilized in EAFs, HBI also offers advantages when used in Blast Furnaces (BFs). It can be employed to increase the productivity of the blast furnace, with studies suggesting an increase of approximately 8% in hot metal production for every 10% increase in the metallization of the burden.12 Simultaneously, the use of HBI can lead to a reduction in coke consumption, with a decrease of about 7% for each 10% increase in burden metallization.12 By adding HBI to the blast furnace charge, more metallic iron is introduced, leading to higher hot metal output.31 The reduced coke consumption also translates to lower carbon dioxide emissions, contributing to a more environmentally friendly operation.12 Furthermore, HBI is easier to handle and charge into a blast furnace compared to scrap and does not typically cause issues like sticking or hanging within the furnace.34 HBI can constitute up to 30% of the blast furnace charge without requiring significant modifications to equipment or processes.31
Benefit | Description | Source |
| Increased Productivity | ~8% increase in hot metal production per 10% increase in burden metallization | 12 |
| Reduced Coke Consumption | ~7% decrease in coke rate per 10% increase in burden metallization | 12 |
| Lower CO₂ Emissions | Due to reduced coke usage | 12 |
| Improved Charging | Easier to handle and charge compared to scrap; reduces operational issues like sticking and hanging | 34 |
| Increased Hot Metal Output | More metallics are introduced into the furnace burden | 31 |
In Basic Oxygen Furnaces (BOFs), HBI can be utilized as a trim coolant [Initial Query]8, offering an alternative to scrap for temperature control during the oxygen blowing process.31 HBI provides an optimal charge for BOFs due to its low levels of residual elements, high bulk density, and predictable mass and heat balances.8 Its cooling effect is approximately 10% greater than that of scrap steel 31, and it does not increase slopping within the furnace compared to using all scrap as the cold charge.31 The low sulfur content of HBI also makes it suitable for producing low sulfur steels.31
Beyond its metallurgical benefits, HBI offers improved safety and efficiency in handling, storage, and transportation compared to DRI, as detailed earlier. Its resistance to reoxidation and lower water absorption make it safer and less costly for ocean transport 4, and its dense, uniform shape simplifies handling and storage using standard equipment.2 These logistical advantages contribute significantly to the overall cost-effectiveness and broader applicability of HBI in the global steel industry.
The primary application of Hot Briquetted Iron (HBI) in the steel industry is in Electric Arc Furnaces (EAFs), where it serves as a crucial feedstock for the production of high-quality steel.4 A significant portion of HBI produced globally, estimated at around 76% of the market share in 2018, is utilized in EAF steelmaking.35 Its low residual element content is particularly valuable for producing steel grades that demand high purity and stringent control over metallic residuals, such as special bar quality steels and flat products.4 HBI can be used in EAFs either in combination with scrap metal or as a direct alternative, offering flexibility to steelmakers based on the availability and cost of scrap.4 In some cases, where scrap is scarce or prohibitively expensive, melt shops may even utilize a charge consisting of 100% DRI/HBI.39 The increasing prevalence of EAF steelmaking, driven by its lower environmental impact and potentially lower operating costs compared to traditional blast furnace routes 15, directly contributes to the growing demand for HBI as a high-quality iron source.
HBI also finds application as a supplementary feedstock in Blast Furnaces (BFs) [Initial Query].4 Its use in BFs is primarily aimed at increasing the production of hot metal and reducing the consumption of coke [Initial Query].4 By replacing a portion of the iron ore burden with HBI, which is already in a reduced metallic state, the amount of coke required for the reduction process can be decreased.42 This is particularly beneficial when a blast furnace needs to maximize its output, for example, during the downtime of another furnace or to meet high demand.31 The application of HBI in BFs demonstrates its versatility and its potential to enhance the efficiency and reduce the carbon footprint of integrated steel plants.
Furthermore, HBI can be used as a trim coolant in Basic Oxygen Furnaces (BOFs) [Initial Query].8 In this application, it serves to control the temperature during the oxygen blowing process [Initial Query]8, offering an advantageous alternative to scrap metal.31 HBI provides an optimal charge for BOFs due to its low levels of residual elements, high bulk density, and predictable mass and heat balances.8 Its cooling effect is approximately 10% greater than that of scrap steel 31, and it does not increase slopping within the furnace relative to using all scrap.31 The low sulfur content of HBI also makes it suitable for the production of low sulfur steels.31 This makes HBI a reliable and effective method for temperature regulation in BOFs, contributing to consistent steel quality.
Beyond these primary applications, HBI is also employed in induction furnaces for the production of various steel grades intended for specialized applications.6 Additionally, its high purity and consistent composition make it a valuable input in the production of various iron-based alloys 6 and as a metallic charge in diverse metallurgical processes.6 These niche applications further highlight the versatility and value of HBI in the broader metallurgical industry.
The global market for Hot Briquetted Iron (HBI) is characterized by several key producing regions, including Russia, the Middle East, North America, and Latin America [Initial Query]. In 2017, Russia emerged as the leading global exporter of HBI, with Metalloinvest being the primary supplier.35 Metalloinvest remains a major global producer of HBI.17 Venezuela is also a significant supplier, with Orinoco Iron being a key player.35 Other notable producers and suppliers include Voestalpine, with operations in Austria and the USA 16; ArcelorMittal, with facilities in Luxembourg and the USA 15; Cleveland-Cliffs in the USA 17; Qatar Steel in Qatar 16; Jindal Shadeed in Oman 17; Essar Steel in India 18; Lisco in Iran 18; Comsigua in Venezuela 17; Lion Group in Malaysia 18; and JSW Steel in India.15 Additionally, Hyundai Steel, Kobe Steel, Sumitomo Metal Industries, Shagang Group, and Nippon Steel are also significant players in the broader steel industry that utilize or potentially produce HBI.15 ArcelorMittal Texas HBI operates the largest HBI production plant globally, with an annual capacity of 2 million tons 22, while Metalloinvest also boasts significant production capacity, exceeding 2 million tons annually for its HBI-3 plant alone.17 Arijco, based in the Middle East, is an experienced exporter of high-quality HBI, particularly serving the Middle East and North Africa regions.3
Supplier | Location(s) | Notes |
| Metalloinvest | Russia | Leading global producer and exporter |
| Orinoco Iron | Venezuela | Key supplier |
| Voestalpine | Austria, USA | Strong presence in Europe and North America |
| ArcelorMittal | Luxembourg, USA | Operates the world's largest HBI plant in Texas |
| Cleveland-Cliffs | USA | First producer of HBI in the Great Lakes region |
| Qatar Steel | Qatar | Key player in the Middle East |
| Jindal Shadeed | Oman | Significant producer in the Middle East |
| Essar Steel | India | Major Indian steel producer with HBI capacity |
| Lisco | Iran | Emerging HBI market |
| Comsigua | Venezuela | |
| Lion Group | Malaysia | |
| JSW Steel | India | Leading Indian steel company |
| Hyundai Steel | South Korea | |
| Kobe Steel | Japan | |
| Sumitomo Metal Ind. | Japan | |
| Shagang Group | China | |
| Nippon Steel | Japan | |
| Arijco | Middle East | Experienced exporter, particularly in the Middle East and North Africa |
The primary consumers of HBI are steel mills worldwide that utilize EAF technology [Initial Query]4 and those seeking to enhance the efficiency and quality of their BF and BOF operations [Initial Query].4 Major consuming regions include Asia-Pacific, which is expected to hold the largest market share due to increasing demand from the automotive and construction industries in China and India 15; North America, driven by the automotive and construction sectors 15; and Europe.16 Specific industries fueling the demand for HBI include automotive, which is the largest application segment 15; construction 15; industrial machinery 15; and infrastructure development.43
The global market for HBI is experiencing significant growth, with various projections indicating robust compound annual growth rates (CAGR), such as 8.39% 15, 11.9% 16, 6.3% 17, 2.2% 18, and 6.1%.19 Market size estimates also reflect this growth, with one analysis valuing the market at USD 94.06 billion in 2024 and projecting it to reach USD 210.56 billion by 2034.15 Other estimates place the market at USD 3.69 billion in 2022, with projections to USD 5.82 billion by 2030 17, or USD 5.15 billion in 2024 reaching USD 6.25 billion by 2033.18 Key drivers for this growth include the surging demand for high-quality steel 4; the increasing focus on environmentally friendly steelmaking practices and the lower carbon footprint associated with HBI [Initial Query]15; the rising adoption of EAF technology in steel production 15; increasing scrap metal prices 19; and significant infrastructure development activities in emerging economies.16
The production and trade of Hot Briquetted Iron (HBI) are often governed by international quality standards to ensure consistency and reliability. Several international organizations, such as the International Organization for Standardization (ISO) and ASTM International, provide relevant standards.4 Specific ISO standards applicable to HBI include ISO 10835:2007, which outlines procedures for the sampling and sample preparation of direct reduced iron and hot briquetted iron.7 ISO 15968 details the methods for the determination of apparent density and water absorption of HBI.7 ISO 15967 specifies the determination of tumble and abrasion indices, which are measures of the physical strength and durability of HBI briquettes.7 For the determination of carbon and sulfur content in HBI, ISO standards such as ISO 15350:2000 and ISO 9686:2006 are utilized.7 Additionally, ASTM International provides various specifications and testing standards relevant to iron and steel products, including HBI.6 The Metals and Mining Standards (MMS) also offer detailed specifications for iron products, including HBI.6 Producers may also adhere to specific national or enterprise-level normative documents, such as TU 0726-003-00186803-2009 used by Metalloinvest.2
Key quality parameters for HBI include the degree of metallization, iron content (both total and metallic), impurity levels, and various physical properties. The metallization degree, which represents the percentage of metallic iron relative to the total iron content, is a critical indicator of the effectiveness of the iron ore reduction process. Iron content, both total and metallic, directly influences the yield and efficiency of the steelmaking process. Impurity levels, particularly of elements like sulfur and phosphorus, are crucial as they can significantly affect the quality of the final steel product. Stringent limits are typically placed on these impurities. Physical properties, such as density, size, shape, and strength (assessed by tumble and abrasion indices), are also important as they impact the handling, transport, and performance of HBI in steelmaking furnaces.
Standardized procedures are employed for the sampling and testing of HBI to accurately assess its quality and ensure compliance with specifications. Sampling should ideally be performed by cutting a complete cross-section of the HBI stream at transfer points using a mechanical sample cutter.7 While manual sampling from conveyors is possible, it requires adherence to safety protocols.7 Sampling from stockpiles is generally not recommended due to the difficulty in obtaining a representative sample.7 Preparation of samples for chemical analysis typically involves a series of steps, including crushing the sample to a specific size (e.g., -12.5 mm), homogenizing it, reducing the sample mass through riffling, further crushing to a finer size (e.g., -2 mm), and finally pulverizing a sub-sample to a very fine powder (e.g., 95% passing -150 µm) for analysis.7 Precautions are necessary during the grinding process to prevent excessive heat generation, which could alter the chemical composition.7 The physical quality of HBI is primarily determined by its apparent density and strength. Apparent density is typically measured using methods described in ISO 15968, involving drying, soaking, and the Archimedes test.7 Briquette strength is evaluated using tumble and abrasion tests, as specified in ISO 15967, which involve rotating a sample of HBI in a standardized drum for a set number of revolutions and then analyzing the remaining material and the amount of fines generated.7 The carbon and sulfur content are usually determined using infrared absorption methods after combustion in an induction furnace, as outlined in ISO 15350 and ISO 9686.7
The production and use of Hot Briquetted Iron (HBI) have significant implications for the environmental sustainability of the steel industry. Notably, the carbon footprint associated with HBI production is generally lower compared to traditional iron production methods, such as the blast furnace route. Natural gas-based DRI/HBI production typically emits considerably less carbon dioxide (CO₂) than blast furnace iron production, with estimates suggesting reductions ranging from one-third the amount 48 to 20-40% less 49, or even 50% fewer emissions.36 The blast furnace-Basic Oxygen Furnace (BF-BOF) route generally exhibits higher CO₂ emissions per tonne of steel produced compared to the Electric Arc Furnace (EAF) route when utilizing HBI.36 Furthermore, the use of HBI in blast furnaces can also contribute to a reduction in overall CO₂ emissions by decreasing the amount of coke required in the process.12
In terms of energy efficiency, HBI production via direct reduction is generally more efficient than traditional blast furnace methods.11 Some sources indicate that HBI production can be twice as energy-efficient as hot iron production.28 Moreover, steelmaking in Electric Arc Furnaces using HBI typically requires less energy compared to blast furnace-based steelmaking 11, with EAFs potentially using only one-eighth of the energy compared to conventional integrated mills.52 The use of HBI in blast furnaces can also lead to reduced energy consumption by lowering the coke rate.11
HBI plays a crucial role in reducing emissions and promoting sustainable steelmaking practices. Its production using natural gas instead of coke results in significantly lower carbon emissions.47 It also enables cleaner steel production by reducing emissions of sulfur and nitrogen oxides.47 The use of HBI supports the increasing adoption of Electric Arc Furnaces (EAFs), which are known for their lower carbon emissions compared to blast furnaces.15 Additionally, HBI production and use can contribute to better resource utilization and recycling efforts within the steel industry.47
Looking towards the future, there is significant potential for hydrogen-based HBI production. Green hydrogen-based HBI is considered a promising pathway for achieving low-pollution iron production.54 Many natural gas-based direct reduction processes are already designed to be H₂-ready 36, allowing for a future transition to hydrogen as the primary reducing agent. Hydrogen-based DRI production has the potential to drastically reduce or even eliminate CO₂ emissions from the ironmaking process.1 However, the current cost of producing green hydrogen remains a challenge for its widespread adoption in HBI production.53
Analyzing the cost of Hot Briquetted Iron (HBI) in steelmaking requires a comparison with alternative iron sources such as steel scrap and pig iron. Generally, the production of DRI/HBI is more expensive than reducing iron in traditional blast furnaces.24 When comparing HBI with steel scrap, current global market prices for HBI are sometimes observed to be slightly higher than those for scrap.24 However, a simple price comparison does not fully capture the economic benefits of HBI. Its consistent quality, higher iron content, and lower levels of impurities can make it a more economically preferable option for steelmakers, a concept often referred to as "value-in-use".24 In some cases, the production of DRI to displace scrap can be a risky venture, particularly when considering market-priced iron ore.59 Historically, steel mills often perceived the use of DRI/HBI as incurring a premium due to factors like higher energy consumption and longer processing times. However, with optimized operating practices, these perceived cost disadvantages can be mitigated, and in some instances, DRI/HBI use can even improve energy efficiency and yield.45
The economic benefits of using HBI extend beyond just the raw material cost. The improved steel quality resulting from HBI's low residual element content allows steelmakers to produce higher value-added steel products, potentially increasing their revenue.24 In Electric Arc Furnaces (EAFs), the operational efficiencies afforded by HBI, such as faster melting rates, the possibility of continuous feeding, and in some cases, reduced energy consumption 45, can lead to significant cost savings.14 Furthermore, the ability to blend HBI with lower-cost grades of scrap while still maintaining the required steel quality can improve the overall economics of the furnace charge.4 In blast furnaces, the use of HBI can lead to reduced coke consumption, which translates directly into cost savings.12 The easier handling and storage of HBI compared to some other iron sources can also contribute to lower logistical costs.47
Several factors influence HBI pricing and overall market dynamics. The prices of key raw materials used in HBI production, primarily iron ore and natural gas, have a significant impact on its production costs.1 The global supply and demand for HBI are closely linked to the overall rates of steel production and the increasing adoption of EAF technology in steelmaking.15 Regional factors, such as the cost of natural gas and transportation expenses, also play a crucial role in determining the final price of HBI in different markets.54 The implementation of environmental regulations and the potential introduction of carbon pricing mechanisms could also influence the relative cost-effectiveness of HBI compared to more carbon-intensive iron production methods.30 Finally, the price of steel scrap, as a major alternative feedstock for steel production, is a key factor that affects the demand and pricing of HBI.24
The future of the Hot Briquetted Iron (HBI) market appears promising, driven by several key trends. There is an increasing global demand for high-quality steel across various sectors, including construction, automotive, and infrastructure.4 This demand necessitates the use of high-purity iron sources like HBI, which allows steelmakers to meet stringent quality requirements for advanced steel grades.18 Simultaneously, the steel industry is under growing pressure to adopt low-carbon steelmaking practices due to increasing environmental concerns and stricter regulations [Initial Query].15 HBI, particularly when produced using natural gas-based direct reduction, offers a significantly lower carbon footprint compared to traditional blast furnace methods, making it an attractive option for steel producers seeking to reduce their environmental impact.36
Advancements in HBI production technologies are also expected to shape the future of the market. There is ongoing research and development in direct reduction processes, including the use of green hydrogen as a reducing agent, which promises to further enhance the efficiency and drastically reduce the carbon footprint of HBI production.6 The integration of automation, digitalization, and artificial intelligence (AI) into HBI manufacturing processes is also anticipated to improve efficiency, quality control, and overall operational performance.6 The concept of "smart HBI," potentially involving integrated sensors for real-time performance monitoring, could also emerge in the future.6
The impact of environmental regulations and sustainability initiatives will be a crucial factor influencing the HBI market. Increasingly stringent regulations on carbon emissions are likely to favor the use of HBI over more carbon-intensive iron sources.1 Government initiatives and incentives aimed at promoting green steel production are also expected to boost the demand for HBI produced through low-carbon methods.54 The use of life cycle assessments (LCAs) will likely become more prevalent in evaluating the environmental performance of different steelmaking routes, further highlighting the benefits of HBI in reducing the overall environmental impact.4
In conclusion, Hot Briquetted Iron (HBI) stands as a vital and increasingly significant commodity within the global steel industry. Its key advantages, including improved handling and safety compared to DRI, the ability to enhance steel quality through low residual element content, operational benefits across various steelmaking furnace types, and a lower carbon footprint than traditional iron production methods, position it as a crucial material for the future of steel production. HBI finds diverse applications, serving as a primary feedstock in Electric Arc Furnaces for high-quality steel production, a supplementary material in Blast Furnaces to increase efficiency and reduce coke consumption, and as a trim coolant in Basic Oxygen Furnaces. The global market for HBI is experiencing robust growth, driven by the rising demand for high-quality steel and the steel industry's transition towards more sustainable and environmentally responsible practices. Looking ahead, the future potential of HBI is substantial, particularly with ongoing advancements in production technologies and the anticipated shift towards hydrogen-based steelmaking. As the steel industry continues to evolve, HBI is poised to play an increasingly critical role in enabling a more efficient, high-quality, and environmentally conscious future for steel production worldwide.