1
Preliminary Risk Analysis Technique for the Design of a New Refinery in Brazil
MSc. Nildemar Corrêa Ruella 1.
ABSTRACT
This work presented the technique of Preliminary Risk Analysis used during the design
of a new oil refinery in Brazil. The technique of preliminary risk analysis included the
application of a checklist and a process flow analysis of all major units, all equipments
and all process of transfer and storage facilities in a manner similar to that achieved
during the approach of HAZOP technique. The application of such PHA technique has
aimed the establishment of design specifications and mitigations actions of health,
environment and safety (HSE) for the new enterprises of new refinery.
Key words: Petroleum Refinery. Preliminary Risk Analysis.
1. INTRODUCTION
The technique of Preliminary Risk Analysis (PRA) presented in this paper was applied
since 2009 on the projects of the following units of the new Brazilian refinery: 2
atmospheric distillation units; 2 delayed coking units; 2 regenerative caustic treatment
units; 2 treatment systems with amines for LPG and Gas streams; 2 diesel hydrotreating
units; 2 naphtha hydrotreating Units; 2 hydrogen generation units; 2 acid waters
treatment units; 2 sulfur recovery units; 2 nitrous oxide emission abatement units; 1
treatment unit for caustic soda; petroleum storage and LPG storage.
The technique of Preliminary Hazard Analysis developed for the Brazilian new refinery
had the following characteristics:
a) Support from senior management;
b) Coordinates by an engineer specialized on the application of risks analysis
techniques, legal and regulatory requirements of enterprises projects focused on HSE;
c) Participation of working groups formed by representatives from various areas of
project engineering (HSE, Civil, Electrical, Instrumentation, Process), operation,
maintenance and inspection;
2
d) Applied in the various phases of the projects of the new units;1
e) PRA average duration of 3 days for the units of process and offsite areas;
f) Comprehensives risks analysis of 100% of the equipments and process main lines in a
sequential process similar to HAZOP;
g) Usage of Quantitative Risk Analysis Study, Environmental Impact Assessment Study
and Environmental Impact Report information.
2. METHODOLOGY
The technique of Preliminary Risk Analysis (PRA) involved the following steps:
I) approval by senior management of the new refinery;
II) definition of professional groups;
III) definition of the resources and of the following project information’s necessary:
a) Process flowcharts;
b) Process data of inputs and outputs of each equipment (Pressure, Temperature, Flow);
c) Chemical composition of the current input and output of each equipment with
emphasis for flammable fractions and hazardous contaminants such as: H2S, NH3,
SOX, NOX, C6H6;
d) Manual Safety Data Sheets of Chemicals;
e) Specification of the process;
f) HAZOP (if available);
g) Climatic and weather characteristics of the region;
h) Data sheet of the main equipments that may contain large inventories of flammable,
fuel, toxic and corrosive products, especially tanks, vessels, reactors, converters;
i) Quantitative risk analysis studies with simulations of consequences and Environment
Impact Assessment/ Environment Impact Assessment Report (if available);
j) Grouding Plant and protection system against atmospheric discharges;
11
Master in Management Systems (UFF). Safety Engineer (UNISANTA). Equipment Engineer
(PETROBRAS). Mechanical Engineer of Production (EFEI). University Professor.
3
k) Cause and effect diagrams (if available);
l) Floor plants of the process units, industrial facilities and buildings;
m) Plant of electrical area classification;
n) Safety plant;
o) Pipe arrangement plant;
p) Firefighting pipes plants;
q) Oil, contaminated, chemical and pluvial drainage systems plants;
r) Passive fire protection plants for steel structures;
s) Passive fire protection plants for electrical ducts of electrical cables and
instrumentation cables;
t) Information about surrounding communities;
u) Information about environmentally sensitive points;
v) 3-dimensional view and if not available, facilities views drawings in perspective;
x) Access to the electronic files of the mentioned documents;
y) Meeting room for up to 12 people equipped with at least two computers with
monitor, a powerful data show, two access points, mouse, keyboard;
z) Facilities for printing drawings;
w) Ruler, eraser, papers for draft, pencil/ mechanical pencil, attendance sheet for
participants, calculator, and markers in multiple colors;
IV) Documents and specifications focused on the HSE used (when available) for
effectively completing the technique of Preliminary Risks Analysis such as: Firefighting
System - Key Plant; Pipes Plant - Firefighting System; Pipes Plant - Firefighting System
– Isograms; Pipes Plant - Deluge System – Isograms; Speakerphone and Telephony;
Pipe & Instrumentation Plants; Deluge System - Safety Flowchart; Safety Plant; Cause
and Effect Matrix for Fire and Gas Detectors and Alarms; Firefighting System; Area
Classification Plant; Data List for Area Classification; Safety System; Closed TV
Circuit; Emergency Lights; Fire Resistant Doors; Fire and Explosion Resistant Doors;
Door of explosion of furnaces, boilers, incinerators; Samplers; Safety Valves;
Grounding and Protection System Against Atmospheric Discharges; Floors; Protection
against fire on electrical ducts; Emergency Vapor Splash; Emergency Manual Trigger;
Status of Emergency Lights; Audible and Visual Signals; Surface Wind Direction
Indicator; Cabinets for Fire Hoses; Portable Fire Extinguisher - Chemical Powder 12kg;
Autonomous Respiratory Protection Equipment for Escape; Portable Fire Extinguisher CO2 6kg; Extinguisher on Wheels - Chemical Powder 50Kg; Industrial Fire Hydrant;
4
Emergency Shower and Eye Washer; Fixed Monitor Cannon – Manual; Fixed Monitor
Cannon – Motorized; Hydraulic Valve; Fire Hoses; Sprinkler; Deluge Valve; Smoke
and Gas Detector and alarm; Emergency Manual Trigger; MR: Audible Signal; Audible
and Visual Signals.
V) Worksheet in Excel or Word must be made before the application of the PHA
containing the following information:
- in the Header: PHA Title; PHA Date of Execution; PHA Review; PHA Location; PHA
Objective; Documents used in the PHA; Copy To; Name, Place of Work and Signature
of the PHA Participant; Unit or Facility; Equipment Identification; Equipment
Description (function); Products chemical composition (input/output); Process data of
inputs and outputs (Pressure, Temperature, Flow); Equipment Data (liquid Volume, gas
Volume, Height, Diameter, Flanges and manholes Height and quantities, etc.); Hazards,
Environmental Aspects or Emergency Situations; Consequences (damage,
environmental impacts or injuries); Causes; Probability; Consequence; Risk Category;
Correctives, Preventives, Eliminator or Mitigation Actions; Responsible for the actions;
Deadline for the actions implementation.
- The PHA Correctives, Preventives, Eliminators or Mitigation Actions field must be
changed in the following columns: Physical arrangement (layout); Detector and Alarm
(gas, steam, smoke, fire); Large inventory blocker valve; Safety or relief valve; Valve
against vacuum; Retention valve; Flame trap; Explosion window (ovens, boilers,
incinerators); Joints (Ex.: Constant load system (coil-plate)); Pumps Seals (type);
Gaskets (type); Torch system; Vents for atmosphere (drainage boxes, atmospheric tanks
and vases); Drainage system (oily, contaminated, chemical and pluvial); Contention
system, dike or basin; System or resources for chemical products neutralization; Roofs
and seals (fixed roof, floating roof, fixed roof with floating seal, etc.); Foam lines (for
tanks); Foam discharges (for tanks); Passive protection against fire on metal structures;
Passive protection against fire on electrical ducts; Resistant doors against fire and/or
explosions; Fixed monitor cannon (manual, electrical (motorized)); Fixed cooling
system by sprinkler; Cooling system manifold valves; 4 outputs hydrant with fixed
monitor cannon; Hydrant; Firefighting equipment cabinet; Prevention steam system;
extinguisher; Individual protection equipment cabinet; Breathing Apparatus; Lit wind
direction and intensity indicator; Emergency Shower and Emergency eye wash; Escape
route; Access (normal and emergency situations); Access (manhole and visitors’ doors);
Inspection windows of burning on furnaces, boilers and incinerators; Flame failure
protection system; Product sampler (type/specification); Chimneys sampler; Manual
Emergency Alarm Trigger (Buttonhole); Audible/Visual emergency alarm; Closed TV
circuit (CTVC); Areas classification; Normal and emergency illumination; Protection
against Atmospherically Discharges System; Grounding; Instrumentation (Detection,
Alarms, Controls, etc); Confined spaces; Process blocker valves station; Utilities
blocker valves station; Equipment sequence as in the process and its done in HAZOP;
Furnaces, incinerator and heaters blocker valves station; Pull point; Chemical products
skid; Firefighting network; etc.
5
VI) After the PHA conclusion reports are generated (RP) containing, for example, the
following informations: 1 Objective; 2 Team; 3 Duration; 4 Analyzed Documents; 5
Management Summary; 6 Recommendations; 6.1 Layout; 6.2 Detectors (of gases,
steams, smoke and fire); 6.3 Valves (of large inventory, safety, relief, retention, block,
against vacuum, flame trap, etc); 6.4 Monitor Cannon; 6.4.1 Fixed monitor cannon
water triggered by remotely valve; 6.4.2 Electric monitor cannon; 6.4.3 Fixed monitor
cannon; 6.5 Hydrant; 6.6 Fixed Cooling System by Sprinkler; 6.7 Drainage System;
6.7.1 Oil; 6.7.2 Contaminated; 6.7.3 Pluvial; 6.7.4 Chemical; 6.8 Passive protection
against fire; 6.8.1 Equipments and metal structures fireproofing; 6.8.2 Passive
protection against fire on electrical ducts; 6.9 Prevention steam system; 6.10
Extinguisher; 6.11 Firefighting cabinet; 6.12 Wind direction and intensity indicator;
6.13 Eye washer shower; 6.14 Escape Route; 6.15 Access; 6.16 Autonomous Breathing
Equipment; 6.17 Emergency Alarm Manual Trigger; 6.18 Audible/visual emergency
alarm; 6.19 Safety valve; 6.20 Flame trap; 6.21 Sampler; 6.22 Manhole; 6.23Explosion
door; 6.24 Protection system against flame failure; 6.25 Exhausted gas analyzer; 6.26
Constant load system (coil-plate); 6.27 Emergency lighting; 6.28 Closed TV Circuit
(CTVC); 7 Next Steps; 7.1 Preliminary Risks Analysis; 7.2 HSE documents; 8
Attachments; Attachment – APR EXCEL SPREADSHEET.xls; SAFETY PLANT
MARKUPS
The Preliminary Hazards and Risks Analysis technique applied on new enterprises
projects has generated quantitative, recommendations, criteria and requirements for:
a) Layout, detachment and arrangement of units, equipments, buildings, etc.;
b) Arrangement definition, location and gas and toxic and flammable steams leak,
smoke and fire detectors and alarms types; emergency alarm manual triggers;
visual/audible alarm device; wind direction and intensity indicators, etc;
c) Definition of equipment that must have large toxic and flammable products inventory
blocker valves; retention valves; safety valves scaled for fire; relief valves,
depressurization valves; vacuum protection valves; flame traps; etc;
d) Project criteria definition and fire water network;
e) Position definition; amount and types of monitors cannons (Electric fixed monitor
cannon, Self-oscillatory fixed monitor cannon, Common fixed monitor cannon); of
hydrants; Firefighting Closet; of fire extinguishers; of sprinklers; of steam applicators;
of applicators and foam lines; litters; autonomous sets; personnel safety equipment;
collective safety equipment;
f) Locations definition and equipments that need passive protection against fire
(Fireproofing) of equipments and metal;
g) Locations definition and type of passive protection against fire on conduits and
electrical ducts;
6
h) Type definition, Amount and positions of oil drainage collection and crossing boxes,
contaminated, chemical e pluvial; containment systems; of leaks; etc.
i) Position definition and shower and emergency eye washer type;
j) Definition of the escape routes; of the emergency doors and stairs;
k) Definition of types and locations of people access;
l) Definition of types and locations of passages, emergency and machinery vehicles
access;
m) Definition of sampler’s position and its type;
n) Position definition and amount of manholes and cleaning doors;
o) Definition of the locations that need emergency lights;
p) Definition of the locations and types of Closed Circuit TV Cameras;
q) Definition of explosion doors position;
r) Definition of types and locations of the furnace exhausted furnace, boilers and
incinerators gases analyzers;
s) Equipments that need constant load joints definition (coil-plate);
t) Leak protections definition and dynamic equipment failures detection and alarm;
u) HSE project documents definition.
CONCLUSION
The Preliminary Hazards and Risks Analysis Technique application adopted on new
enterprises projects may bring the following benefits:
a) HSE risk reduction;
b) Project delays risks reduction;
c) Investments values reduction;
d) Reworks and change management reduction;
e) Reduction of number of project documents;
f) Equipment and project criteria standardization;
h) Maintenance and inspection costs reduction;
i) Licensing and authorization deadlines reduction;
j) Insurance values reduction.
7
Suggestions for the onshore industrial units plant arrangement project improvement
a) Capacitate enterprises risks analysis professionals in a MBA or Master’s course
taking as a theoretical base the standards and techniques of risks analysis, HSE laws and
HSE technical standards (Petrobras, ABNT, API, NFPA, etc), contemplating the
practical application realization at the new Supply large;
b) Create in the Business Units, in the enterprises managements, HSE management
sectors containing an expert in project risk analysis and management.
c) Create in the Business Units risk analysis coordinators, as done with the rehabilitee
coordinators;
d) Create consultants in the process, projects and enterprises risks analysis.