Hydrocarbon fires hazards

There are four main hazards ship collision, dropped objects, fire, and explosion. Specially, the topsides of the offshore platform, which treats combustible oil and gas, are always exposed hydrocarbon fire hazards bring out a high consequence disaster. Moreover, damages from fire accidents have increasingly been astronomical in accordance with the growing scale and complexity of the recent plants, as seen in the Deepwater Horizon incident. 

Even though the FRA has made much advance in recent decades, most types of them have overlooked inherent uncertainty. HSE (2006) defines several sources of uncertainty in the FRA for hydrocarbon fire hazards as shown in Figure 2. They proposed inaccuracy and incompleteness from selecting representative scenarios and considered conservative assumptions to deal with uncertainty in the consequence and frequency estimation. 

Not to be Used Water, foam, carbon dioxide, or halogenated hydrocarbons Special Hazards of Combustion Products No data Behavior in Fire Reacts violently with water, forming flammable and explosive hydrogen gas. This product may spontaneously ignite in air Ignition Temperature No data Electrical Hazard Not pertinent Burning Rate Not pertinent. 

Cellulose nitrate Air drying Solvent evaporation Blends of esters, alcohols and aromatic hydrocarbons Fairly good Bad Good Poor Very good Fire hazard Statutory regulations governing use... 

So the handling of hydrocarbons presents serious fire hazards. There are many accidents linked to this in the industrial sector. For instance, a serious accident happened when polyethylene was stored. It appeared to be caused by the diffusion of monomer through the mass of polymer, which created an inflammable atmosphere in the storage container. Incorporating a mixture of oxygen and styrene in a reactor cause spontaneous ignition. 

Since potassium will burn in air, it is important to cut, slice, or powder the metal under an inert hydrocarbon solvent such as kerosene, toluene, or xylene. The air in the reaction flask should be displaced by an inert gas such as nitrogen. In this manner, fire hazard in handling potassium metal will be minimized. 

All fixed fire suppression system control valves should be located out of the fire hazard area but still within reach of manual activation. For high hazard areas (such as offshore facilities), dual feeds to fire suppression systems should be considered from opposite areas. For onshore facilities, firewater isolation valve handles should not be contained within a valve pit or a below grade enclosure within the vicinity of hydrocarbon process facilities, since heavy process vapors travel from the process and may settle inside. 

Before discussing the FHA process in detail, it is important to have an understanding of the fire hazards present at chemical, petrochemical, and hydrocarbon processing facilities. 

Where the need for fire detection is identified, the required performance of the fire detection system is already specified as part of the grading process. Fixed fire detection is typically installed to protect equipment that is high value, long lead time, or likely to be significant fire escalation hazards. The performance specification defines fire size and response time thresholds for alarm and action(s). Fire hazards are defined by radiant heat output (RHO). RHO gives a reasonable indication of the potential damage and the probability that the fire will escalate or cause loss. The RHO should not be used to determine fire thermal loading onto equipment and structures. Table 8-3 compares RHO and flame area for some typical hydrocarbon fires. 

The attractions of a drying agent which forms a homogeneous mixture with the substance to be dried, e.g. triethyl aluminium or dibutyl magnesium with hydrocarbons and some other compounds, are obvious the former can be used with methyl methacrylate, the latter with styrene and with dienes. However, it is questionable whether the difficulty of separating the dried compound completely from unused drying agent and the fire-hazard associated with many metal alkyls make the effort worth while, except in some special cases. 

Hydrocarbons are derivatives from petroleum or crude, but within the context of our immediate discussions, we shall use the terms petroleum liquids and hydrocarbon liquids as being interchangeable. From a fire standpoint, there are only two categories of petroleum liquids, namely flammable liquids and combustible liquids. Both categories of materials will bum however, it is into which of these two categories that a liquid belongs that determines its relative fire hazard. Of the two categories, it is the flammables that are considered to be more hazardous, principally... 

Virtually all plastic foams are blown with inert gases (COs. Ns. H 0). Among these blowing agents, hydrocarbons and some of the HCFs and HFCs are flammable ajtd pose a fire hazard in handing al the manufacturing plants. 

Violent reaction between Al chlorinated hydrocarbons) 92)MCA General Safety Comm, "Guide for Safety in the Chemical Laboratory , Van Nostrand, NY (1954) 234 pp (Includes a tabulation of fire-hazard props of flammable liquids, gases volatile solids)... 

The potential fire hazard presented by waste tire stockpiles has been realized a number of times in the past decade. Several stockpiles have burned until their tire supplies were exhausted which, depending on weather conditions, may be a few days to more than a year. Air pollutants from tire fires include dense black smoke which impairs visibility and soils painted surfaces. Toxic gas emissions include polyaromatic hydrocarbons (PAHs), CO, S02, NOj, and HC1. Following tire pile fires, oils, soot, and other materials are left on site. These tire fire by-products, besides being unsightly, may cause contamination to surface and subsurface water as... 

Beyler, C.L. Fire hazard calculations for large, open hydrocarbon fires. In SFPE Handbook of Fire Protection Engineering, 3rd Edition. Quincy, MA Society of Fire Protection Engineers, 2002, pp. 3-268-3-314. 

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