Security and Safety Process Safety and Dangerous Goods ... · PDF fileexplosion...
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Explosion characteristics Tests can be performed to determine the explosion characteristics of a specific dust at various initial conditions. These characteristics include: • Explosive properties; • Lower explosion limit (LEL); • Minimum Oxygen Concentration (MOC); • Maximum explosion overpressure (P max) ; • Maximum explosion pressure rise ((dP/dt) max ,K St -value); • Minimum Ignition Energy (MIE); • Minimum Ignition Temperature of a dust cloud (MIT); • Minimum Ignition Temperature of a dust layer (smouldering temperature). At non-atmospheric process conditions (high pressure/temperature), research can be done in the specially developed strengthened 20-litre sphere. DV2 05d41 Process Safety and Dangerous Goods Dust Explosions Security and Safety Explosion prevention and protection Combining facilities and expertise we are able to assist you with: • Audits of process installation regarding explosion safety; • Advice on zoning in accordance with the European ATEX regulations; • Risk assessment and evaluation; • Accident analysis; • Analysis of the explosion effects to the surroundings; • Advice on preventive and protective mea- sures. Combustible powders can form explosive mixtures when in contact with or dispersed in air. Dust explo- sions can occur in many different processes, e.g. in the food processing, pharmaceutical and chemical industry. Compared to gas explosions, the influence of the dust and process characteristics (like type, concentration, particle size distribution and moisture content) on the explosion behaviour is much more complex. Combined with a thorough theoretical background, the knowledge gained from realistic experiments forms the basis for handling safety problems regarding dust explosions. Over the years, TNO has performed dust explosion research that led to more knowledge about the behaviour of dust explosions. 1m 3 -vessel for explosion tests.
Transcript of Security and Safety Process Safety and Dangerous Goods ... · PDF fileexplosion...
Explosion characteristicsTests can be performed to determine the
explosion characteristics of a specific dust at
various initial conditions.
These characteristics include:
• Explosive properties;
• Lower explosion limit (LEL);
• Minimum Oxygen Concentration (MOC);
• Maximum explosion overpressure (Pmax);
• Maximum explosion pressure rise
((dP/dt)max, KSt-value);
• Minimum Ignition Energy (MIE);
• Minimum Ignition Temperature of a dust
cloud (MIT);
• Minimum Ignition Temperature of a dust
layer (smouldering temperature).
At non-atmospheric process conditions (high
pressure/temperature), research can be done
in the specially developed strengthened
20-litre sphere.
DV
20
5d4
1
Process Safety and Dangerous Goods
Dust Explosions
Security and Safety
Explosion prevention and protectionCombining facilities and expertise we are
able to assist you with:
• Audits of process installation regarding
explosion safety;
• Advice on zoning in accordance with the
European ATEX regulations;
• Risk assessment and evaluation;
• Accident analysis;
• Analysis of the explosion effects to the
surroundings;
• Advice on preventive and protective mea-
sures.
Combustible powders can formexplosive mixtures when in contactwith or dispersed in air. Dust explo-sions can occur in many differentprocesses, e.g. in the food processing, pharmaceutical andchemical industry. Compared to gasexplosions, the influence of the dustand process characteristics (liketype, concentration, particle sizedistribution and moisture content)on the explosion behaviour is muchmore complex. Combined with athorough theoretical background,the knowledge gained from realisticexperiments forms the basis forhandling safety problems regardingdust explosions. Over the years,TNO has performed dust explosionresearch that led to more knowledgeabout the behaviour of dust explosions.
1 m3-vessel for explosion tests.
Security and Safety
Dust Explosions
ResearchResearch is being carried out continuously to
maintain TNO’s knowledge position.
In order to do so, we participate in interna-
tional research projects with various subjects
like ignition behaviour and explosion effects.
Experimental research is performed on
scaled-down models or on a realistic
geometrical scale.
‘TNO Defence, Security and Safety’ is the titleunder which TNO operates as a strategic partnerfor the Dutch Ministry of Defence and makesinnovative contributions to enhance the safetyand security of the Netherlands both at homeand abroad. We also use our accumulatedknowledge for businesses, industries andforeign governments.
N.H.A. VerslootT +31 15 284 3465F +31 15 284 3997
Lange Kleiweg 137P.O. Box 452280 AA RijswijkThe Netherlands
TNO Defence, Security and Safety
Process Safety and Dangerous Goods
Within the field of safety of dangerous goods and industrial processes,
we offer services on:
• Process safety;
• Product safety;
• Explosion safety and control;
• Product and process optimisation.
Whenever possible, we endeavour to give added value to your investment in safety by
combining safety with (economic) optimisation of design, maintenance,
control and production. A team of specialists is available to apply the expertise for
finding a solution to your problem.
Please visit our website at: www.tno.nl/prosafe
0dust concentration [g/m3]
250 500 750 1000
0
5
10
min
imum
igni
tion
ener
gy(m
J)
humidity (%wt)0
min
imum
igni
tion
ener
gy(m
J)
161284
10000
1000
100
10
0
tapiocamaize
wheatflour
aluminium
polyetheen
min
imum
igni
tion
ener
gy(m
J)
median diameter (µm)10 25 50 100 250 500
10-1
100
101
102
103
104
KSt =(dP/dt)max•V1/3
Explosion class KSt-value
St 1 <_ 200 St 2 200 < KSt <_ 300St 3 > 300
