In industrial plants, boilers are among the most critical heat-generating equipment, making them susceptible to fire hazards.
About Petrochemical plants
The definition of “Plant” means physical equipment required to produce a principal product and related by-products. A plant may consist of one or more number of process units to produce final products. Process plants consist of various types of process equipment like vessels, reactors, columns, pumps, compressors, etc. In addition, to processing plants, the facility or compound of oil & gas installation consists of utilities and ancillaries like power plants etc.
About Fire detection and fire protection systems
In industrial plants, boilers are among the most critical heat-generating equipment, making them susceptible to fire hazards. Proper fire detection and protection systems are essential for boiler houses to prevent explosions, overheating, and fuel-related fires.
Fire Protection is the study and practice of mitigating the unwanted effects of fires. Installing fire protection systems in a plant is statutory under the Factories Act & Indian Electricity Act. Precautions to be taken in case of fire, as per Section 38 of the Factories Act are as under:
- All practicable measures are to be taken to prevent the outbreak of fire and its spread, both internally and externally.
- Provide safe means of escape for all persons/employees/staff and workers.
- Provisions of necessary equipment and facilities for extinguishing the fire.
- Workers are to be made familiar with the safe practices while working and trained to take safety precautions.
Fire Protection system is broadly divided into two main classifications (i.e.) Active Fire Protection system and Passive Fire Protection system.
Active Fire Protection system (AFP) is an integral part of fire protection, and it is characterized by items and/or systems, which require a certain amount of motion and response into work, contrary to a passive fire protection system.
About the importance of Passive Fire Protection system
In boiler rooms and steam plants, passive fire protection plays a key role in preventing heat-induced structural damage. Fireproof insulation, refractory linings, and fire-retardant coatings help contain high temperatures, reducing the risk of fire spread in case of fuel leaks or overheating.
Passive Fire Protection (PFP) system is an integral part of the three components of structural fire protection and fire safety in buildings. PFP attempts to “contain” fire or “slow” the “spread” through the use of fire-resistant “walls, floors, and doors”.
A passive measure like fireproofing/insulation or fire retardant coating will provide protection in the initial stage of fire which is very crucial. This will give some breathing time for activating other fire-fighting measures like starting fire pumps, organising people, and opening valves etc. This will take care of automation failure wherever it is provided.
Details of Facilities of Petrochemical Plants
Types of Oil & Gas installation and PC plants
Refineries and PC plants include oil & gas installation and downstream petrochemical industries. It involves the production of chemicals and other materials derived from petroleum. Oil & Gas installation, which includes oil wells (both onshore & shore), gathering centres, gas booster & transfer stations, oil & gas pipeline network including pumping stations, crude oil plants, refining units, HC gas & liquid bulk storage tanks farms. Refining units consist of several process units (i.e.) distillation units and recovery units for gases & hydrocarbons.
Layout of Oil & Gas installation and PC plants
The typical layout of a petroleum refinery and petro-chemical plant consists of the following group of units and other related utilities & facilities:
- Several process units to produce a principal product and related by-products, in refinery and PC plants.
- Bulk Tankages or Tank Farms and Pipe & cable racks.
- Utilities or Auxiliaries including power generation.
- Miscellaneous Buildings – workshop, offices, lab, fire station, etc.
Fire & Explosion Hazards in Petrochemical Plants
The oil & gas and petrochemical industries are prone to major accidents such as fire and explosions. Boilers, which operate at high pressures and temperatures, pose additional fire risks due to fuel combustion, overheating, and steam leaks. The main factors of fire & explosion are due to the physical and chemical properties of raw materials & finished goods, how they behave under different operating conditions and also due to the large quantities of materials (i.e.) hazardous chemicals, solvents, etc. handled in large-size reactors in a single stream.
The various causes of fire & explosion hazards and allied perils are as under:
- Pressure build-up & chemical reactions
- Equipment failure, Corrosion/Erosion & Leaks
- Ignition sources
- Human error, Hot work, Chemical storage & Storage tank overfills
- Natural disasters (Earthquake, Cyclone, Flood & Lightening)
- Static electricity, Inadequate ventilation
- Fuel leaks and Combustion risks
- Overheating and Pressure Build-Up
- Electrical short circuits
Hazard classification of occupancy of process blocks, storage tanks, utility areas and miscellaneous buildings is based on the fire load only. The details of fire load and hazard classification are as under:
Table – 1 – Details of Fire load and Hazard classification
Details of Fire fighting systems applicable for Petrochemical plants
To minimize or reduce the risks involved in the process, various active and passive fire protection systems & equipment are installed in chemical plants. The fire detection & extinguishing systems are designed on the basis of the hazard category of occupancy of each process block/storage tank. A list of various fire protection & safety systems and their application are mentioned in the following tables.
Table 2 – List of Active Fire Protection systems & applicable areas
Table 3 – List of Passive Fire Protection systems & applicable areas
Summary:
This article has highlighted the critical role of Passive Fire Protection Systems in mitigating fire hazards in petrochemical plants. While active fire protection plays a crucial role in immediate fire suppression, passive fire protection measures such as safe plant layout, fireproof coatings, fire-rated walls, and blast-resistant structures are essential for preventing fire spread and minimizing damage.
In the next part, we will delve deeper into advanced fireproofing methods, including structural fire protection, fire sealing techniques, and blast-resistant construction, which are vital for enhancing the overall fire safety of petrochemical plants. Stay tuned as we explore how meticulous planning and implementation at the design stage can significantly improve industrial fire resilience.
Author:
T.K.Chandrasekaran
Risk Engineering Consultant & Fire Safety Engineer
