hydrogen risk assessment in são paulo state – brazil newton pimenta sandro tomaz giuseppe...
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Hydrogen risk assessment in
São Paulo State – Brazil
Newton Pimenta
Sandro Tomaz
Giuseppe Michelino
4th International Conference on Hydrogen Safety
ICHS 2011
12 - 14 September 2011
San Francisco, CA, USA
198_NevesN
FONTES: IBGE, DETRAN-SP
São Paulo State (SP)
Municipalities: 645
Population: 41 million inhabitants 95% urban
Gross Domestic Product: 34% of the country
21 million vehicles
108,000 industries
SP Environmental Protection Agency (CETESB)
CETESB Main Objectives
Evaluation of environmental quality Air - Water - Soil
Inspection of environmental pollution sources
Technology transfer in the environmental field
Prevention - environmental licensing
Main focus is outside the walls.
VILA SOCÓ - CUBATÃO CITYVILA SOCÓ - CUBATÃO CITY
04/Feb/1984
GASOLINE PIPELINE RUPTURE
FOLLOWED BY FIRE
Source: Banco de Imagens da CETESB/1984
Source: Petrobrás
500 victims
93 deaths
Environmental Licensing
Previous and Installation License Operational License
Risk Analysis(RA)
Licensing - Prevention
CE
TE
SB
’s R
isk
Ana
lysi
s F
low
char
t
Hazardous substanceand quantity (RD)
Off-site Vulnerability
QRA?
ConsequenceAnalysis
FrequencyAnalysis
Off-site scenarios selection
Risk estimation (Societal & Individual)
Need risk reduction?
Risk reduction measures
Risk Management Program
NO
YES
NO
YES
Risk Management Program (RMP)
Process Safety Information Management of Change Operating Procedures Training Assuring the Quality and Mechanical Integrity of
Critical Equipment Emergency Response and Control Investigation of Incidents Audit of Risk Management Systems
Comparison: QRA x RMP
Quantitative Risk Analysis: Expensive Subject to greater uncertainties Time-consuming
Risk Management Program Not expensive Simple Less time used in analysis
Reference Distance supports the decision-making
Reference Distance (RD)
Reference Distance (RD) Maximum distance reached by 0.1 bar overpressure
from vapour cloud explosion (1% death). Instantaneous release of 20% of the inventory
of a vessel/tank Cloud dispersion to Lower Flammability Limit (LFL) Vapour Cloud Explosion (VCE) Software PHAST 6.54 determines the “worst case”
consequences for an explosion. Chart: RD x Mass
Hydrogen RD Chart and VCE
Mass (kg) RD (m)
10 18
50 30
100 38
500 65
1,000 81
1,500 93
10,000 175
100,000 378
LFL
Reference Distance (m)
Leaksource
Cloudcenter
Distance to 0.1 bar
Hydrogen RD ChartVapour Cloud Explosion
Parameter ValuePasquill Atmospheric Stability DWind Speed 2 m/sAmbient Temperature 25ºCRelative Humidity 80%
Simulation : weather conditions
QRA
Risk Management Program (RMP)
Population inside RD circle?
RD Application
YES
NO
Example of RD Application
Four interconnected hydrogen vessels, each one with 250 kg (total 1,000 kg)
Chart indicates a RD of 81 m
Is there population inside the RD circle? From the figure the answer is YES
Conclusion: the facility must submit a full QRA to CETESB
Example of RD Application
Discussion
The assumptions may be conservative in some cases. For example: it does not consider any protective system
Initial screening
Covers storage cases
Not for continuous process
Conclusion
Not the worst case, but conservative Simple, easy to aplly and cheaper Money / time saving
Thank you! Obrigado!
Brazilian Reference Centerfor Hydrogen Energy
Hydrogen Laboratoryat Unicamp
Contacts:Sandro Tomaz [email protected] Michelino [email protected] Newton Pimenta [email protected]
São Paulo Environmental Protection Agency