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This project is funded by the European Union Projekat finansira Evropska Unija . INTERNAL EMERGENCY PLAN Seveso II CAse in Romania. Ike van der Putte. Pilot Site Major-Accident Identification and Risk Assessment. General. Site selected was the integrated chemical
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This project is funded by the European Union Projekat finansira Evropska Unija INTERNAL EMERGENCY PLAN SevesoII CAse in Romania Ike van der Putte
Pilot Site Major-Accident Identification and Risk Assessment
General • Site selected was the integrated chemical • fertiliser plant SOFERT S.A. in Bacau. • SOFERT consists of the following production • areas: • Ammonia plant (Kellogg) commissioned in 1979 with a capacity of 300,000 tonnes/year • Ammonia is produced by reacting nitrogen with hydrogen at high pressure (157 bar) • Ammonia storage tank of 15,000 tonnes with filling for road and rail tankers • Urea plant (Stamicarbon) commissioned in 1981 with a capacity or 420,000 tonnes/year • Urea is produced by reacting ammonia with carbon dioxide at a pressure of 130 bar
General (Continued) • Sulphuric Acid-Monohydrate Plant (Romanian design) commissioned in 1978 with a capacity of 400,000 tonnes/year • Phosphoric acid plant (Romanian design) commissioned in 1979 with a capacity of 110,000 tonnes P2O5 /year • Complex Fertilisers Plant (Diammonium phosphate) a Romanian design commissioned in 1978 with a capacity of 28,700 tonnes nitrogen/year and 100,000 P2O5 /year
SOFERT and Seveso II Directive • Ammonia is classified as toxic by inhalation • (R23), with the Seveso II thresholds of: • 50 tonne lower tier • 200 tonne top tier • With the 15,000 tonne site ammonia storage • capacity, the top tier threshold is exceeded by • a factor of 30.
HAZOP Review • A HAZOP review of the ammonia storage tank and associate equipment was completed by SOFERT technical staff, Project Management Specialists, Local Experts, the Ministry of Waters and Environmental Protection and representatives from the local Environmental Agency. • The purpose of the HAZOP was to demonstrate the technique and review the ammonia tank, the area of the plant with the highest risk.
Photograph of Ammonia Storage Tank with Ammonia Transfer Station in Foreground Photograph of Ammonia Storage Tank Showing Containment Bund
HAZOP Review (Continued) • A full report was generated for the HAZOP study itemising causes, consequences, safeguards and action items • Two actions resulted: • 1. Relief valve sizing calculations were not • available • 2. Investigate the use of foam in combating • a spill of liquid ammonia in the tank bund
Major Hazard Identification Study • Site was broken down into individual areas and assessed by same team • Hazard screening was carried out for each individual hazard identified by assessing the elements of risk, i.e. likelihood and consequences, following hazard identification • Hazard ranking was completed, using the risk matrix, to highlight all credible major accident hazards
Example of Major Accident Hazard Identification Record Sheet Ammonia Plant
Category 1 Hazards Identified Major-Accident Hazards
Consequence Assessment • Representative worst case scenarios were developed and used for evaluation purposes • For the hydrogen leak the following were assessed: • - Flammable Hazards: Thermal radiation from jet flame and/or pool fire. • - Explosion Hazards: Explosion overpressures due to vapour cloud explosion • For the ammonia leak and storage tank; toxic hazards due to toxic vapour dispersion
Modelling Exercise • Software package PHAST (Process Hazard Analysis Software Tools) used for modelling the scenarios • Weather data for Bacau provided by local Enviroment Agency • Two conditions used for modelling: • 1. Stability class B (moderately unstable) and wind speed of 1 m/s • 2. Stability class F (very stable) and wind speed 2 m/s
Modelling Exercise (Continued) • B1 represents worse conditions for dispersing toxic vapours than occurs 68% of the time. It is typical of weather conditions experienced in Bacau. • F2 represents the worst possible conditions for dispersal of toxic vapours. It only occurs 2.6% of the time in Bacau.
Toxic Exposure Levels used in Consequence Assessment • From interm (USA) Acute Exposure • Guideline Levels (AEGL) for ammonia.
Toxic Exposure Levels used in Consequence Assessment(Continued) • AEGL-2 is the concentration above which it is • predicted that the general population, • including susceptible individuals, could • experience irreversible or other serious, • long-lasting adverse health effects or an • impared ability to escape.
Ammonia Storage Tank Rupture • Worst case scenario; catastrophic rupture of the full storage tank. Ammonia pool formed in bund (64 m x 64 m). Ammonia will vapourise from pool. Maximum Distance from the Centre of the Pool to Reference Toxic Concentrations at Ground Level
Ammonia Storage Tank Rupture(Continued) • The values obtained from the leak in the ammonia supply line rupture to the urea plant were considerably smaller
Hydrogen Leak in Ammonia Plant • Hydrogen is supplied at high pressure, 130 bar to the ammonia plant. The 400 mm diameter pipe was modelled for jet fire and vapour cloud explosion • The results indicate that personnel could suffer injury and that minor structural damage could occur up to 1,340 m from the release. Serious damage to equipment and buildings is likely to occur up to 640 m from the release
Recommendations • Water cannons at each side of bund should • be converted to foam usage. A foam blanket • will reduce significantly the ammonia • vapourisation rate for approximately 45 mins. • The use of double containment tanks for • similar ammonia storage is now required (e.g. in • the United Kingdom). This would reduce • significantly the pool of ammonia that would • occur on tank failure
CAseRomania Results from Pilot Site Internal Emergency Plan
Background • The SOFERT site is located in the south eastern corner of Bacau. The immediate area is predominately heavy industry and agriculture. The main Bucharest to Bacau rail line forms the western border of the site • SOFERT has developed an internal emergency plan for the site based on an ammonia release
Background • The plan is based on ammonia concentrations downwind of a tank rupture of 12,000 m (Lethal) and 40,000 m (Toxic)
Structure of SOFERT Plan • The plan is structured in six chapters: • 1. Preventative Measures • 2. Chemical and Physical Properties of Ammonia • 3. Responsibilities in Event of Emergency • 4. Organisation for Protection and Emergency • Response • 5. Damage Remediation • 6. Plan for Action Procedure with Alarm as • a result of damage to Ammonia Tank or • Pipeline
Structure of SOFERT Plan (Continued) • There are seven annexes to the plan: • 1. Contact telephone numbers for key personnel • 2. Table showing dispersion distances calculated from a graph in the Civil Defense Guide • 3. Map of site • 4. Map of Bacau district • 5. Evacuation plan for personnel • 6. Toxic cloud dipsersion results • 7. Plan for emergency response and first aid teams and available equipment
Structure of SOFERT Plan (Continued) • The emergency control centre (ECC) has been sited according to the prevaling winds relative to the ammonia tank location • There is a back-up location of the ECC for the opposed wind direction
Testing of SOFERT Plan • Emergency response practise drills are carried out for the general site every three months • Monthly exercises are carried out for the individual chemical areas • Every two years there is a practice drill with the external Civil Defense team
Findings of Plan • The plan contained the core elements required by Seveso II, namely: • - A defined management structure for • emergency response • - Emergency response teams with appropriate • equipment • - An on-site and off-site alarm procedure • - Regular training in emergency response
Recommendations • The plan has been developed around an • ammonia release. While the principles of • emergency response have been incorporated • into the plan they do not address other • identified hazards such as fire and explosion. The plan therefore needs to be expanded to cover these scenarios
Recommendations(Continued) • The plan needs to be reviewed, tested and where necessary revised and updated by the operators and designated authorities at suitable intervals of no longer than three years (Article 11 (4)). This needs to be incorporated into SOFERT procedures
References COUNCIL DIRECTIVE 96/82/EC of 9 December 1996 on the control of major-accident hazards involving dangerous substances(OJ L 10, 14.1.1997, p. 13) – consolidated version DIRECTIVE 2012/18/EU OF THE EUROPEAN PARLIAMENT AND OF THE COUNCIL of 4 July 2012 on the control of major-accident hazards involving dangerous substances, amending and subsequently repealing Council Directive 96/82/EC Planning for Emergencies Involving Dangerous Substances for Romania. Final Report. Contract no: RO-0081.0011.01. 11 February 2012. I.van der Putte: Regional Environment Accession Project (REAP). Nethconsult/BKH Consulting Engineers/RPS. Subcontractors: AEA Technology, URS/Dames & Moore, EPCE, Project Management Group, REC Hungary