Dangers of Shipping Direct Reduced Iron (DRI)
The designation “direct reduced iron,” or DRI, encompasses a myriad of products, each possessing distinct properties and potential risks. Alarmingly, several inquiries concern DRI types that charterers and shippers deem neither perilous nor restricted. They often employ terms like “HBI,” “hot briquette,” “fines,” “remet,” and “metallic fines” not just for precise product classification, but frequently to bypass charterparty stipulations on transporting hazardous cargo.
It’s crucial to recognize that the label DRI, commonly seen in charterparties, broadly encompasses numerous products, each with its unique attributes and threats. Furthermore, this term also provides a detailed elucidation of a refined iron ore variant. For the International Maritime Organization’s Safe Practice Code for Solid Bulk Cargoes (BC Code), these items are classified under direct reduced iron categories (DRI BC 015 or HBI BC 016). The purpose of this composition is to equip ship masters and proprietors with the ability to discern permissible offers and the necessary safety measures.
DRI, primarily appearing as sponge pellets or lumps measuring between 6 and 25mm, often averages between 8 to 12mm. Classified by the IMO BC Code as a substance hazardous in bulk quantities (MHB), it’s listed under BC015. Upon exposure to moisture, it’s prone to significant overheating, emitting hydrogen gas. Thus, it necessitates transportation under inert conditions, typically employing nitrogen gas, applied through a temporary manifold before loading. It’s imperative to position thermocouples within the cargo and ensure consistent gas monitoring throughout the voyage. The product’s preservation in dry conditions is paramount, and it’s categorized as DRI, BC 015.
HBI, or hot briquetted iron, derives from DRI, compressed at temperatures surpassing 650°C to form briquettes. This product, significantly safer than DRI pellets, displays heightened resistance against overheating upon moisture exposure. It might emit negligible hydrogen quantities during transportation, but the BC Code doesn’t demand inerting—only adequate surface ventilation. Provided there’s no supplementary qualification, it falls under HBI BC 016.
Cold briquetted iron (CBI) is crafted from residuals birthed during the creation of related ferrous commodities and semi-processed raw materials like DRI. Notably, CBI retains certain pivotal DRI characteristics due to its production at temperatures below 650°C. Hence, CBI’s propensity to overheat and release hydrogen persists when wet. If its origin remains dubious, treat it akin to DRI, BC 015.
DRI fines, the byproducts of DRI production, often measure 4mm or less. These fines behave analogously to DRI pellets, necessitating similar precautions. One salient risk lies in their potential exposure to moisture during storage, which can manifest issues during transit. Thus, they align with the DRI, BC 015 categorization, and knowledge of their storage history is vital.
The term “HBI fines” is sometimes employed to potentially attain leniencies in shipping requirements. If these fines materialize post the HBI briquetting process, they may exhibit safety comparable to HBI briquettes. However, any ambiguity regarding their origin warrants treatment as DRI, BC 015.
“Remet fines” and “Remet fines (HBI)” misleadingly hint at a re-melting process but should be regarded as DRI, BC 015. Similarly, “metallic HBI fines” align with this classification. Any term diverging from the BC Code, such as “Orinoco iron remet fines,” necessitates treatment as DRI, BC 015.
In conclusion, adherence to SOLAS Chapters VI and VII, along with the IBC Code, mandates the provision of pertinent documentation concerning the intended cargo. Owners must exercise caution regarding offers under abbreviated names, demanding comprehensive product descriptions. It’s anticipated that future BC Code renditions will preserve current DRI categories but delineate them as either “A” or “B.”
In essence, any iron cargo labeled as “fines” or described with terms absent in the BC Code should conform to DRI product specifications in BC Code No. 015. The shipper bears the burden of proof to demonstrate the fines’ origin outside DRI production. In the face of uncertainty, vessels are advised to seek expertise.
Carriage of Direct Reduced Iron (DRI) by Sea
It’s imperative to acknowledge the prevalent apprehensions associated with the maritime transportation of Direct Reduced Iron (DRI). Such trepidations have escalated markedly subsequent to the tragic fatalities from the YTHAN (2004) event and the intentional submersion of the ADAMANDAS (2003) by French Officials with its cargo and bunkers intact.
MV Ythan catastrophe, marked by a devastating explosion and lamentable loss of lives, stemmed from the reaction between the ship’s “HBI Fines” cargo and the inherent moisture at the loading juncture. The contemporary IMO Code of Safe Practice for Solid Bulk Cargo — termed “the Code” — differentiated two DRI variants: the hot moulded briquettes or hot briquetted iron (later termed as DRI (A)), and pellets and lumps, later coined as DRI (B). The DRI/HBI fines defied classification under these categories, and expert counsel recommended its categorization under the more volatile DRI (B).
Post these incidents and the ensuing probes, the IMO’s Sub-Committee on Dangerous Goods, Solid Cargoes, and Containers (DSC) contemplated revisions to the Code’s pertinent schedules. The collective of the Marshall Islands, Intercargo, and the IG posited the unique classification of DRI Fines as DRI (C), and mandated the transportation of both DRI (B) and (C) within an inert nitrogen ambience, capping moisture content at 0.3% for DRI (C). In September 2008, during its 12th assembly, the DSC advocated these modifications to be ratified by the IMO’s Maritime Safety Committee (MSC). The latter endorsed these in November 2008, leading to the Code’s rechristening as the International Maritime Solid Bulk Cargo Code (IMSBC Code).
Enumerated below are the salient amendments to the Code concerning the transportation of DRI (A), (B), and (C):
DRI (A), Briquettes, hot-moulded:
- Moisture content ceiling at 1%.
- The cargo predominantly consists of intact briquettes with fines under 6.35mm and dust restricted to 5%.
- Hydrogen concentration mandates monitoring; should it exceed 25% LEL, requisite precautions are essential.
- Surface ventilation is occasional; mechanized ventilation demands explosion-resistant fans with anti-spark features.
- Protective wire mesh required over ventilation apertures.
DRI (B), Lumps, pellets, cold-moulded briquettes:
- Standard particle size ranges from 6.35mm to 25mm, with fines below 6.35mm and dust capped at 5%.
- Loading mechanisms must remain dry.
- Prior to the loading phase, rigorous testing is requisite to ascertain hatch covers’ watertightness.
- Moisture levels should stay under 0.3% and warrant continuous surveillance during loading.
- Immediate offloading of any dampened or reactive cargo is imperative.
- Exclusive transportation under an inert gas veil is permitted.
- Vessels must possess the means to consistently monitor cargo temperature and assess hydrogen and oxygen concentrations while minimizing inert atmosphere loss.
- Departure is contingent on meticulous evaluations, ensuring cargo spaces are sealed, inerted, stabilized cargo temperatures, and hydrogen concentration within stipulated limits.
- Oxygen levels are to remain under 5% for the entirety of the voyage.
DRI (C), By-products, Fines:
- Standard particle dimension falls below 6.35mm with an absolute absence of particles exceeding 12mm.
- The erratic nature of this cargo’s reactivity necessitates perennial caution.
- Carriage mandates mirror those of DRI (B), inclusive of the 0.3% moisture threshold and the inert gas blanket provision.
To further elucidate, an exhaustive synopsis of the DRI transportation prerequisites under the IMSBC Code has been appended. However, it remains paramount to adhere to the Code’s comprehensive provisions.
Given the aforementioned directives, entities transporting DRI (B) or (C) should rigorously ascertain that the chosen vessel can consistently sustain oxygen concentrations under the 5% threshold throughout the journey.
Direct Reduced Iron (DRI) Products Shipping Requirements
DRI (A), Briquettes, Hot-Moulded:
• The humidity level must not exceed 1%.
• The consignment should predominantly consist of whole briquettes; inclusion of fines is strictly forbidden.
• Fines must not constitute over 5% of the total weight.
• All weather deck enclosures and hatch coverings must undergo thorough inspection and testing to guarantee their robustness and resistance to the elements.
• Only surface ventilation shall be implemented as required, avoiding direct airflow into the main cargo bulk.
• In instances where mechanical ventilation is utilized, the fans must be certified explosion-resistant and must mitigate any spark formation. Protective wire mesh should cover both ventilation inlets and outlets, ensuring no gaseous escape towards residential areas.
• When unloading, a delicate misting of freshwater is permitted solely if the cargo is destined for outdoor storage.
DRI (B), Lumps, Pellets, Cold-Moulded Briquettes:
• The average particle dimension should range between 6.35mm to 25mm, with fines not exceeding 5% in weight.
• The shipping certificate must specify the manufacturing date for each cargo batch.
• The post-loading certificate should validate that the moisture content remains within acceptable parameters.
• Cargo must be either aged for a minimum of 3 days or undergo equivalent treatment to reduce its activity equivalently.
• Cargo must remain dry at all junctures. Wetted cargo, or any suspected of moisture exposure, is deemed unsuitable for loading.
• Conveyor systems used for loading should be dry.
• Before loading, an ultrasonic examination or a comparable methodology should be performed to ensure the hatch coverings and closures are watertight.
• Moisture content should not surpass 0.3% by weight and needs consistent monitoring during the loading process.
• If the loaded cargo becomes dampened or exhibits reactive signs, immediate unloading is imperative.
• Breakages of briquettes and lumps should be curtailed, and incorporating fines is strictly forbidden.
• Transport is only authorized under a blanket of inert gas.
• Before loading, arrangements for introducing dry inert gas at the tank’s pinnacle are necessary. Nitrogen is the preferred choice. All ventilation points must be secured to retain the inert ambiance.
• After filling a cargo compartment, it should be sealed promptly and suffused with inert gas to maintain an oxygen concentration below 5% throughout.
• Vessels must possess reliable mechanisms to measure internal temperatures at various stowage points and gauge hydrogen and oxygen levels in the cargo airspace during transit, whilst minimizing inert atmosphere disruption.
• Oxygen levels should be held below 5% for the entirety of the journey. Vessels should be equipped to uphold this standard consistently during transit.
• Before embarking, both the ship’s captain and a qualified individual acknowledged by the loading port’s national administration must confirm:
- That all cargo chambers are properly sealed and filled with inert gas;
- Temperature consistency across all measurement points is below 65°C;
- Hydrogen concentration in the open space remains under 0.2% by volume (or 5% LEL).
• Throughout the voyage, cargo chambers must stay hermetically sealed, preserving the inert state.
• Ships must be furnished with a device designed to measure oxygen in combustible environments.
• Oxygen levels should undergo periodic evaluations during transit.
• In the event of rain, all unloading actions must cease, and compartments housing cargo should be sealed.
DRI (C), By-Products, Fines:
• The average particle dimension should not exceed 6.35mm, and no particle should be larger than 12mm.
• Due to the diverse composition of this cargo, its reactivity remains challenging to gauge. Consequently, one should always anticipate the most adverse conditions.
• The moisture content of the cargo should always remain within permissible limits.
• Transport prerequisites align with those for DRI (B), including the 0.3% moisture constraint, save for the following deviations:
- The shipping certificate isn’t mandated to detail each cargo batch’s production date;
- Cargo should have undergone a 30-day aging process.
- If cargo, once loaded, encounters additional freshwater or seawater beyond its innate moisture level, becomes damp, or exhibits reactions elevating its temperature beyond 120°C, immediate offloading is obligatory.
Dangers of carrying Direct Reduced Iron (DRI)
Types of Direct Reduced Iron (DRI)
Direct Reduced Iron (DRI) serves as the quintessential precursor in the fabrication of steel utilizing electric arc furnaces, the predominant method of steel-making globally. DRI can be broadly categorized into two refined classes: cold-molded pellets and hot-molded briquettes. The International Maritime Organization’s Bulk Cargo (BC) Code delineates these types separately. The hot-molded DRI briquettes, being more sophisticated, emerge from further refinement of the cold-molded pellets. Both manifestations of DRI are deemed perilous in bulk transport, with specific transport directives outlined in the BC Code.
Characteristics and Perils of Direct Reduced Iron (DRI)
Direct Reduced Iron (DRI), in its diverse forms, mirrors other steel constructs in its propensity to corrode or re-oxidize in the presence of oxygen. The velocity of this oxidation is contingent, variably, upon the DRI’s moisture quotient and the surrounding ambiance. This oxidative reaction produces heat, which can be profoundly intense in mass shipments of DRI. Augmented by moisture, particularly when the water encompasses dissolved chlorides found in seawater, this oxidation accelerates. The spongy configuration of DRI constrains heat dispersion, thus enabling swift temperature escalations in isolated clusters.
When hot iron intersects with water, it instigates a chemical reaction, culminating in the genesis of hydrogen—a gas with a formidable propensity for explosions when present in specific proportions. This volatile attribute of DRI has been the precursor to numerous tragic detonations. In certain fabrication methodologies, DRI undergoes specific procedures known as ‘passivation’, where the briquettes receive a sodium silicate veneer, or ‘ageing’, permitting the briquettes to develop an iron oxide facade. These procedures aim to mitigate or restrain the oxidation whilst in transit, a matter thoroughly addressed in the BC Code.
Carriage Requirements for Direct Reduced Iron (DRI) by Sea
Outlined within the IMO BC Code are the stipulations concerning carriage. It is essential to also refer to the most recent counsel and standards sanctioned by the regional Competent Authority and dispensed by the shipping entity. The BC Code advocates that shipping parties extend precise guidelines regarding the transport of DRI, which can be:
- The containment areas should remain in an inert state, with an atmospheric composition of below 5% oxygen. It’s essential that hydrogen within these containment areas remains below 1% in volume, OR
- Ensure the DRI undergoes a manufacturing or treatment procedure with an oxidation-retardant method to the satisfaction of the Competent Authority.
If the ambience is rendered inert, the sole permissible inerting agent is nitrogen. Utilizing carbon dioxide is proscribed, chiefly due to its potential to generate carbon monoxide – a compound that’s both hazardous and combustible. Even for abbreviated maritime journeys, it’s proposed that the shipment remains entirely inert. While passivation can demonstrably curb oxidation resulting from freshwater intrusion temporarily, its protective efficacy diminishes over an extended period. It’s crucial to acknowledge the minimal protective measures against swift reactions induced by saltwater permeation into the containment areas. As a protective measure, it’s emphatically suggested that DRI transportation be consistently executed under a protective layer of nitrogen.
Ship personnel must diligently surveil the atmospheric constitution within the cargo zones, logging hydrogen and oxygen levels in each compartment. It’s pivotal to vigilantly observe the cargo’s state during the loading phase. Any cargo that’s excessively warm or moist should be eschewed. Furthermore, it’s proposed that cargo’s temperature during the loading phase be under scrutiny. Should the cargo’s temperature surpass the surrounding temperature, counsel must be procured from the regional Competent Authority. Yet, cargo exhibiting a temperature above 65°C must invariably be rejected. Typically, thermocouples are positioned within the cargo holds for cargo temperature surveillance during transit. Ensuring these thermocouples are assiduously assessed before placement within the cargo and noting their precise placement is paramount.
Additionally, it’s advocated that cargo be meticulously arranged to diminish the exposed surface area to ambient conditions. Proper trimming also mitigates the “funnel” effect, curtailing void spaces within the cargo where heated gases ascend, simultaneously attracting fresh air. Should a vessel harbor any uncertainties regarding a specific DRI consignment, procuring impartial counsel from a specialized authority is fervently recommended.
Iron Fines that may contain Direct Reduced Iron (C)
The methodology involved in producing Direct Reduced Iron (DRI) from iron ore, coupled with the subsequent hot briquetting processes, invariably leads to the emergence of undesirable by-products in the guise of dust and fractured chips throughout its stages. Certain manufacturers ingeniously salvage these remnants and propose them for dispatch. Traditionally, these cargoes predominantly hailed from Venezuela and Trinidad, albeit dispatches were occasionally observed from regions like the US, Mexico, and Libya. Such shipments have, lamentably, been the catalyst for several tragedies, with the most infamous being the MV YTHAN catastrophe in 2004. This incident witnessed the tragic demise of six onboard crew members due to blasts in four of her five cargo chambers, culminating in the ship’s forfeiture.
Surprisingly, such cargo wasn’t explicitly acknowledged in earlier iterations of the Bulk Cargo Codes. After prolonged deliberations, a revamped schedule was conceived to incorporate this material. This inclusion found its place in the 2009 version of the IMSBC Code, which was decreed as obligatory from 1 January 2011. The latest rendition of this Code was promulgated this annum. The listing is labelled as DIRECT REDUCED IRON (C) (By-product fines), and its characterization exclusively focuses on aspects of its creation, granular dimensions, and mass, sidelining any mention of its metallic iron or dampness quotient.
In the face of widespread awareness campaigns, there remain cargoes on offer that conspicuously lack DRI in their descriptors. Yet, these are composites housing a considerable quantum of DRI (C) fines. These cargoes have been denoted using varied nomenclatures, such as reoxidised iron fragments, iron residues amalgamations, iron ore splinters, oxide remnants, lagoon residues, muck remnants, remets, clarification mud, residue, spent iron fragments, and lodos. A few analogous cargoes explicitly mention DRI, but are vended under the presumption that they are distinct from DRI (C) and hence, aren’t governed by the DRI (C) Schedule of the Code. Stakeholders should prudently recognize that even if a cargo isn’t categorized as DRI (C), its proximity to DRI stockpiles can lead to inadvertent adulteration with DRI fragments. This memorandum offers insights to Shipowners, Captains, and Charterers regarding the requisite data for identifying DRI consignments and the optimal, secure protocols for their transportation.
To eliminate any ambiguities, the standpoint of the International Group of P&I Clubs (IG) is unequivocal: cargoes incorporating DRI in their nomenclature ought to be pronounced using the suitable Bulk Cargo Shipping Name (BCSN) for a DRI (C) consignment and must be organized, embarked, and transported in congruence with the stipulations of the IMSBC Code.
Loading Direct Reduced Iron (C) on Ship
Before embarking upon the task of loading, essential details should be amassed. Cargo blends labeled as DRI (C) can be discerned based on their distinctive chemical constituents. It is imperative to solicit these intricacies. Such compositions should elucidate the aggregate content of iron (Fe), the unalloyed iron presence (Feo), and the moisture levels. Ideally, this knowledge should bear the endorsement of an impartial research laboratory and must correspond to the exact cargo proposed for transport; to put it more clearly, a non-specific analysis won’t suffice. The certificate must illuminate the procedures and benchmarks employed during the sample collection and assessment, with a nod to ISO 10835: 2000 for the former, and BS ISO 5416 : 2006 for the latter. One should also be circumspect about the date of the sample collection to guarantee its pertinence.
Iron embedded within the confines of an iron ore cargo is inextricably linked to other components, leaving no room for unalloyed iron. Should there be an inkling of metallic iron (Feo) in the cargo, it undeniably traces its lineage to a DRI offshoot: The DRI categories (A) and (B) generally boast a metallic iron concentration of around 85%, but this figure might plummet to a mere 1% or 2% in the DRI (C) blends. These amalgamated cargoes bear the mark of the treacherous DRI (C) and must be transported in alignment with the prescribed Code. If ensnared in uncertainty, it would be judicious for Members to seek guidance from their respective Associations.
Once the cargo’s identity aligns with DRI (C), the IMSBC Code delineates the crucial data to be furnished to the captain. Beyond the overarching stipulations, the dictum for DRI (C) accentuates:
“Antecedent to the loading act, the consignor is obligated to equip the captain with an attested document, authored by a qualified individual acknowledged by the National Administration of the embarkation harbor. This document must vouch for the cargo’s aptness for transport at the moment of loading, its adherence to this Code’s mandates, its moisture quotient falling below 0.3%, and a temperature ceiling of 65°C. This testament should confirm the cargo’s congruence with the pre-established loading parameters in terms of maturity and thermal conditions.”
“Before the cargo commences its voyage, it must undergo a maturation period spanning at least 30 days, verified by a certificate from a credentialed individual, again endorsed by the National Administration of the port of departure.”
“Consignors are charged with the duty of imparting exhaustive details about the cargo, as well as the requisite safety protocols to be activated during emergencies, to the captain prior to loading.”
“Throughout the loading procedure, vigilant observation of the cargo temperature is non-negotiable. A meticulous record, delineating the thermal metrics for every cargo segment, must be maintained, and a facsimile handed over to the captain. Post the loading chore, a seal of approval, furnished by a sanctioned individual recognized by the National Administration of the port of embarkation, is paramount. This approval must validate that across the entire batch, especially the fines and minuscule fragments, the moisture level remains restrained below 0.3% and the temperature never surpasses the 65°C threshold.”
IMSBC Code and DRI (C)
Regarding exceptions to the stipulations laid down in the IMSBC Code, cargoes enumerated in Appendix 1, notably DRI (C), are noteworthy. Section 1.5 grants permission for a proficient authority to sanction alternative provisions or exceptions, provided they are convinced such substitutes parallel, if not surpass, the safety measures mandated by the Code. Three esteemed authorities are recognized: the originating port state, the destination port state, and the flag-bearing state. If a shipment is safeguarded by such an exemption, the exemption’s beneficiary is duty-bound to alert the other involved authorities, whose concurrence with the exemption remains discretionary.
The IG acknowledges a minimum of three nations, Venezuela, Trinidad and Tobago, and Mexico, that propose DRI (C) cargoes, possessing moisture content as high as 12% and metallic iron ranging between 1% and 60%, under the protection of exemption certificates from the originating port state’s proficient authority. The existence of any Tripartite Accords among the other esteemed authorities remains obscure. However, the IG emphasizes that at least two flag-bearing states strictly forbid any deviations from the IMSBC Code concerning any DRI variant.
While the Association concedes the Code’s provision for exceptions, it fervently counsels members to abide by the IMSBC’s specifics for DRI (C). Should members opt otherwise, they must assure themselves of unanimous notification and assent from the three aforementioned authorities, adherence to the flag-bearing state’s rules, and retention of the exemption certificate onboard vessels ferrying solid bulk cargoes under said exemption.
Cargoes transported under such exemptions mandate explicit protocols for loading, transport, and safety. The shipmaster must be comprehensively informed of essential parameters like ventilation rates, explosion safeguards for ventilation apparatus, ventilation duct layout, monitoring protocols for hydrogen levels and cargo temperatures, emergency criteria, and requisite actions in crisis scenarios, including shipper contact details. Furthermore, prior to and during offloading, certain procedures must be adhered to.
The IMSBC Code’s framework for DRI (C) caps the moisture content at 0.3%. Cargoes exceeding this threshold are deemed non-compliant, and if saturated further, they pose genuine liquefaction threats akin to certain iron and nickel ore shipments. Hence, any pertinent declaration must categorize the cargo under both Group A and B, and the accompanying documents should specify both the Transportable Moisture Limit and the actual moisture content of the consignment. These papers should exclusively pertain to the specific shipment in question, eschewing any generalized data from prior consignments.
Lastly, the IMSBC Code addresses those cargoes not enumerated in Appendix 1. Such shipments can be transported under conditions delineated by a tripartite agreement amongst the ports of loading and unloading and the flag-bearing state. Nevertheless, if any cargo, described perhaps as iron ore fines or analogous terms, is discovered to have even a trace of metallic iron content (Feo), it ought to be classified as DRI (C) and transported in alignment with the Code’s mandates, since the tripartite agreement pertains solely to cargoes absent from Appendix 1 of the Code.