CAER Safety Summit meet December 2010. Doug Jeffries Chief Fire Protection Engineer
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Agenda
Definitions and chemistry of pyrophorics Conditions inevitable to pattern pyrophoric iron sulfide Where pyrophorics have been known to frame of reference in refinery equipment Possible methods to mitigate and prevent pyrophoric related incidents A couple example pyrophoric related incidents .
© 2010 Chevron
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© 2010 Chevron
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Definitions
A pyrophoric material is a liquid or solid that, even in teentsy quantities and without an external ignition source, can ignite within 5 minutes after coming in contact with air1 In oil and petrochemical industry, this only partially defines the concern. We also need to be concerned with the fact the pyrophoric material can create catch fire which can ignite residual hydrocarbons associated with the equipment containing the pyrophoric material. Example pyrophoric materials include alkali metals and many organometallic combines such as alkylmagnesiums, alkylzincs, and of course pyrophoric iron sulfide.
Nickle carbonyl in some catalysts
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Chemistry of Pyrophorics
Pyrophoric compound + oxygen (typically air) compound + heat Sometimes with several intermediate reaction move Can be precise reactive or very slow to react
Oxide of the
Can vary with conditions, humidity, temperature, particle size, degree of outlay in air, etc.
Bottom line: pyrophorics can be a very elusive and tricky animal to recognize and nonplus until it bites you
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© 2010 Chevron
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Conditions required to form pyrophoric iron sulfide
H2S concentration > 1% (can form at lower concentrations but typically not in concentrations that are a concern) Iron scale or rusty (FeS) Less than a 1:1 ratio of oxygen to H2S (some oxygen is required to form the rust but if shy(predicate) oxygen is present the reaction with H2S cannot go to...If you want to take off a full essay, order it on our website: Ordercustompaper.com
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