Importance of fireproofing in metallic structures of oil installations

Introduction

Fireproofing involves complex challenges when it comes to securing industrial facilities; however, none compares to the magnitude and complexity of fireproofing in a refinery. These facilities, characterized by the handling of highly flammable materials and large-scale processes, present a significant risk that requires optimal planning and advanced technological solutions.

Although safety, including fireproofing, is a fundamental pillar in the oil industry, there are facilities that continue to operate without complying with international standards. Potential incidents in the metallic structures of the facilities highlight the urgent need to review and improve protection strategies. This article addresses the magnitude of refinery fireproofing, highlighting critical vulnerabilities and proposing comprehensive approaches to improve operational safety.

Main fire hazards associated with metallic structures in oil installations

Factors contributing to the risk of fire in metallic structures

• Flammability of processed materials: The presence of flammable or combustible materials in industrial processes increases the risk of fire in metallic structures due to their high susceptibility to ignition in the event of leaks or accidents.
• High operating temperatures: The use of equipment such as boilers, furnaces and reactors operating at high temperatures represents a constant source of ignition, significantly increasing the risk of fire.
• Valve and piping systems: Poorly designed valves and piping or without an adequate pressure relief system can be critical hazard points, especially if handling high-pressure fluids that can release enough energy to start a fire.
• Adverse environmental conditions: External factors such as proximity to other industrial facilities, exposure to natural phenomena such as hurricanes or earthquakes, and the possibility of accidental impacts (e.g., from aircraft) are elements that can cause fires in metal structures.
• Static electricity: The accumulation of electrostatic charges during the handling of flammable fluids at temperatures above their flash point can cause ignition.
• Inadequate fireproofing: Lack of adequate fireproof coatings on metal structures supporting critical equipment can result in rapid fire spread and structural collapse during a fire.

Case studies of previous incidents

Deflagration at Repsol Puertollano (Ciudad Real, Spain, 2003)

This accident was triggered by the presence of a possible gas pocket in a crude oil distillation tower or on the floating roof of a gasoline tank¹. The contact of this gas pocket with a heat or electrical source caused a deflagration, which triggered a series of fires in the nearby gasoline tanks. The heat generated by the fire was so intense that it prevented immediate intervention by emergency crews, demonstrating the risk posed by uncontrolled heat sources in combination with the accumulation of flammable gases in metal refinery structures.

Suncor Energy Inc. fire (Alberta, Canada, 2005)

The fire started due to the burning of hot vapors emanating from the base of a fractionation tower that splits hydrocarbon vapors into different fractions such as naphtha, kerosene and gasoil¹. Extreme weather conditions, with temperatures of -34ºC, complicated the work of the firefighters. The extreme cold caused the oxygen regulators and equipment to freeze, making extinguishing operations even more difficult. The fire presented a high risk of spreading to other plant units due to the highly flammable nature of the fuels involved.

This case illustrates how adverse environmental conditions can hinder the fireproofing process in metal structures by increasing the risk of fire spread and causing further damage.

BP Refinery Explosion and Fire (Texas, United States, 2005)

The explosion occurred when the engine of a pick-up truck ignited a large cloud of flammable vapor from an atmospheric vent in the isomerization unit1. This incident was exacerbated by organizational and safety deficiencies detected at the plant, including lack of effective supervision and cutbacks in necessary safety investments. The result was a tragedy that caused 15 deaths and 180 injuries, in addition to property damage valued at approximately US$1.5 billion.

This unfortunate event highlighted the dangers of inadequate safety management in refineries, where metal structures can contribute to the spread of devastating fires.

Methods and technologies currently used to protect metallic structures from fires in oil installations

Passive protection systems

• Intumescent coatings: These are applied directly to metal structures. In case of fire, instumescent coatings expand and form a carbonized layer, insulating the metal structures from heat.
• Fireproof mortars: They consist of a mixture of calcium sulfate, light aggregates and other chemical materials with thermal insulation properties, applied on structures to protect them against fire.
• Insulating panels or plates: They are installed on metallic structures, providing an insulating barrier against fire, thus preventing its propagation.

Active protection systems

• Automatic water sprinklers: They are designed to activate automatically when a fire is detected, spraying water to reduce the surrounding temperature and control the fire.
• Foam systems: Used to cover structures and extinguish fires, especially in areas with risk of hydrocarbon spills. Its use increases the effectiveness of water as a fire extinguishing agent.
• Inert gas systems: Used in enclosed areas to dilute oxygen to values that allow extinguishing the fire without harming the lives present in the facilities.

Monitoring and detection

• Temperature and smoke sensors: Detect changes in environmental conditions and warn of possible fires, automatically activating active protection systems.
• Thermal cameras: Monitor the temperature of metal structures and allow rapid intervention in case of temperature increase.

Regular maintenance and testing

• Periodic inspections: These are carried out to ensure that all protection systems are in good working order and meet the required standards.
• Functional tests: Their objective is to guarantee the proper functioning of the components of the protection systems. The way to achieve this is by means of simulations and tests that ensure the effectiveness of such systems.

Regulations governing fireproofing

API RP 2001

This standard provides a detailed technical framework to ensure industrial safety, based on a series of fundamental principles that regulate fireproofing in metallic structures present in refineries. These principles are:

• Risk assessment: This stage involves identifying and analyzing potential fire hazards in refineries, considering factors such as the nature of flammable materials, the layout of the facilities, and possible ignition sources.
• Fire prevention: API RP 2001 establishes guidelines to minimize risks through safe facility design, equipment maintenance and hazardous substance management. Personnel training is essential to proactively identify and mitigate risks.
• Fire response systems: The requirements for detection systems, alarms, and evacuation plans are detailed, emphasizing the importance of well-trained teams for a rapid and coordinated response to fires.

The combination of these API RP 2001 principles results in a comprehensive and systemic approach to fireproofing, ideal for ensuring refinery safety in an efficient manner.

NFPA 1700

It is technical guidance focused on structural firefighting, providing detailed guidelines for firefighters on planning, response and attack tactics in fire situations².

In the context of refineries, it is a particularly relevant standard due to the complexity and risks associated with metallic structures and flammable materials. The standard emphasizes the importance of pre-fire planning and coordination, covering processes such as risk identification and assessment, as well as the development of response plans that include coordination between different fire departments and emergency agencies².

One of the main focuses of the standard is the initial fire response, where the emphasis is on continuous situation assessment and strategic decision-making. In metal refinery structures, this assessment is critical to allocate resources and adjust tactics as the fire evolves.

In addition, it also addresses attack tactics and controlled ventilation, essential for managing fires in complex structures. The NFPA 1700 guidelines provide a comprehensive and up-to-date framework for protecting metal structures in refineries, optimizing safety and efficiency in fighting these types of events.

Impact of fireproofing on metallic structures

Metal structures, which form a fundamental part of oil facilities, can quickly lose their structural integrity when exposed to the high temperatures generated by a fire. This can lead to partial or total collapse of the infrastructure, increasing the damage and risk to human life.

For this reason, the use of protection methodologies, equipment and systems is essential to prolong the fire resistance of structures, providing the necessary time for optimal evacuation and the intervention of emergency teams. In addition, fireproofing helps to minimize economic and material losses by avoiding the total destruction of facilities in the event of large-scale fires.

Conclusions

Fireproofing is a concept of great importance in safety, especially in highly complex facilities such as refineries, where highly complex materials are handled. Among the threats affecting this sector are the risks associated with metal structures, thus generating the need to implement advanced protection systems.

The historical accidents discussed above are indicative of the urgency of adopting comprehensive approaches, as well as implementing strict regulations that can result in the development of higher safety standards in the industry. Effectively employing such a system of strategies allows for better damage mitigation in the event of a fire and additionally ensures the operational continuity of these critical facilities.

References

1. Gómez, E. (2012). Protección contra incendios en refinerías [Master’s thesis, Universidad Pontífica Comillas]. https://technokontrol.com/pdf/proteccion-refinerias.pdf
2. Moncada, J. (2023, 8 de febrero). Áreas críticas de protección en refinerías petroleras. Accessed on August 13, 2024 from https://especificarmag.com.mx/areas-criticas-de-proteccion-en-refinerias-petroleras/