1. Occupational Hygiene in the
Oil & Gas Industry
Day 2 – Section 8
Production Processes
Oil Refineries

2. Overview of Refining Processes – Fuel & Lubes
Separation of crude oil into various fractions.
Gas – LPG (Propane, Butane)
Gasolines, Naphthas – Petrol, Avgas, Solvents
Kerosenes – Home kerosene, Jet Fuel, Light Heating Oils, Solvents
Diesels – Automotive diesel fuel (ADO)
Fuels oils – Bunker fuel
Bitumens – Road making, other products
Lube Oil Feedstock – production of Lube oils
Petrochemical Feedstock – plastics production
Overview of Refining Processes
The refining process of crude oil is complex. Processing plants essentially separate the crude oil into various fractions, and then by an organised and coordinated arrangement of manufacturing processes (designed to produce physical and chemical changes by conversion, separation and treatment), produce marketable product such as LPG (Propane, Butane), gasoline (petrol), kerosene (jet fuel), diesels, fuel oils, bitumens, lube oil feed stocks, and petrochemical feed stocks.
Separation of crude oil into various fractions.
Gas – LPG (Propane, Butane)
Gasolines, Naphthas – Petrol, Avgas, Solvents
Kerosenes – Home kerosene, Jet Fuel, Light Heating Oils, Solvents
Diesels – Automotive diesel fuel (ADO)
Fuels oils – Bunker fuel
Bitumens – Road making, other products
Lube Oil Feedstock – production of Lube oils
Petrochemical Feedstock – plastics production

3. Refineries Refinery - land based, fixed installation
Close to coast or river systems for shipping
Connect to markets by pipelines
Loading facilities to receive crude oil and feed stocks
Load-out facilities to distribute products
Crude supplied by ship, pipeline or rail car.
Capacity 100, ,000 Bbls/day
Smallest <50,000 Bbls/day (<8 million Litres/day to
Largest 1,000,000 Bbls/day (180 million Litres/day)
The refinery is always a land based, fixed installations, usually close to the coast or river systems for shipping, connected to the markets by pipelines. It has loading facilities for receipt of crude oil and feed stocks, and load-out facilities for the finished products. Crude oil is supplied by ship or by pipeline or rail car.
The capacity of a refinery can vary from small (<50,000 barrels per day (bbl/day)) or 7.95 Mega litres per day) to the largest (in 2008), SK Energy Ulsan Refinery in South Korea with a capacity of 840,000 bbl/day (134 Mega L/d). This has now been surpassed by a million barrels per day refinery in India. Most are in the range 100,000 to 300,000 bbl/day.

4. Typical Layout of Fuels Refinery
A refinery is always noticeable for the large amount of storage tanks required for (a) crude oil storage to ensure continuous operation of the refinery – usually the largest tanks (b) intermediate products/feed stocks from the primary distillation, and (c) finished product tankage for distribution to the market. These are called ‘tank farms’
The process units are usually grouped close together as many share heat exchange (hot products from one unit exchanging the heat and becoming cooler by heating up the feedstock for using heat exchangers. This saves energy. There are perhaps over a hundred heat exchangers in a refinery). The process units also need the same utilities –water, electricity, steam, instrument air, drainage, cooling water (from cooling towers), environmental monitoring systems, safety showers, etc.
Office, admin and Maintenance workshops, laboratories etc. are usually placed away from the process units.
There are always waste water treatment separated from the process units, easily identified as treatment or effluent ponds which drain to creeks, or rivers, or the sea.
Typical Layout of Fuels Refinery

5. Typical Layout of Fuels Refinery Process Units
This is Altona Refinery, Melbourne, Australia (circa 2000) and shows 2 atmospheric crude distillation units, both a Thermofor Cat Cracker (TCC – shutdown) and a Fluidized Cat Cracker (FCC), Alkylation unit (Sulphuric type), Naphtha Fractionation, Plat-Reformers, Benzene Reduction Unit, Catalytic Hydrodesulphurisation Unit CHD for removal of sulphur compounds, Sulphur Recovery Unit (to recover the sulphur from sour gas)tory
Saturated Gas Plant, Bitumen plant, Cooling Towers, Gas Spheres (for storage), LPG Storage and load-out facilities.
To the far left – the laboratory
Typical Layout of Fuels Refinery Process Units

6. Process Flow – Fuels Refinery Distillation
Atmospheric Crude (oil) Distillation unit – primary distillation of crude oil into fractions based on boiling range
- gas, naphtha, kerosenes, middle distillates (gas oils) and residual oils (‘bottoms’)
Vacuum Distillation – the secondary distillation of residual oils from atmospheric distillation to make feedstock for the Catalytic Cracker and feed stocks for bitumen plants or lube oil refining
8.2 The Process Flow – Fuels Refinery
The simplest way to understand a refinery operation is to follow the process flow diagram (Figure 2.8), this will illustrate the various refinery process units and how they are connected.
The basic process units of all fuels refineries comprise the following:
Atmospheric Crude (oil) Distillation unit – the first primary distillation of the crude oil into gas, naphtha, kerosenes, middle distillates (gas oils) and residual oils (‘bottoms’)
Vacuum Distillation – the secondary distillation of the residual oils to make feedstock for the Catalytic Cracker and feed stocks for bitumen plants or lube oil refining
Then the various conversion processes
Catalytic Cracking unit (usually a Fluidised Catalytic Cracking unit (FCC); some Thermofor Catalytic Cracking units (TCC) may still be in use).
These units take the residual oils (bottoms) and ‘crack’ the heavy molecules into lighter fractions gas, naphtha, middle distillates (gas oils) and heavy oils.
Figure 8.3 – FCC Unit showing the Large Reactor and Fractionating Towers
(Source: Petroch Services)
Catalytic Reformers, which take the low octane naphtha and catalytically reform the molecules in a hydrogen rich atmosphere to make high octane gasoline blend stocks
Alkylation Unit for the conversion of light hydrocarbon gases (propylene, butylene with iso butane) using an acid catalyst (Sulphuric or hydrofluoric, or phosphoric acid) to produce high octane (liquid) gasoline blend stocks
There are many other process units are described in Figure 8.4.
For more information on petroleum refining, refer to:
accessed Aug
US OSHA Technical Manual, SECTION IV: CHAPTER 2, PETROLEUM REFINING PROCESSES
accessed Aug

7. Distillation Fractions
Carbon Number
Boiling Range
Name
Deg. C
Deg. F
C1-C4
<0
<30
Gas
C4-C12
0-200
30-392
Naphtha
C12-C15
Kerosene, Jet Fuel
C15-C25
Gas Oil, Heating Oil, Diesel
>C25
>400
>750
Bottoms, Residuum, Vacuum Distillation Feedstock

8. Process Flow – Fuels Refinery Conversion Processes
Catalytic Cracking unit (FCC), (TCC) - residual oils (bottoms) ‘crack’ heavy molecules into lighter fractions gas, naphtha, middle distillates (gas oils) and heavy oils.
Catalytic Reformers - low octane naphtha, change molecules in a hydrogen rich atmosphere to make high octane gasoline blend stocks
Alkylation Unit - light hydrocarbon gases (propylene, butylene with iso butane) combined to produce high octane (liquid) gasoline blend stocks, using Sulphuric or hydrofluoric, or phosphoric acid
8.2 The Process Flow – Fuels Refinery
The simplest way to understand a refinery operation is to follow the process flow diagram (Figure 2.8), this will illustrate the various refinery process units and how they are connected.
The basic process units of all fuels refineries comprise the following:
Atmospheric Crude (oil) Distillation unit – the first primary distillation of the crude oil into gas, naphtha, kerosenes, middle distillates (gas oils) and residual oils (‘bottoms’)
Vacuum Distillation – the secondary distillation of the residual oils to make feedstock for the Catalytic Cracker and feed stocks for bitumen plants or lube oil refining
Then the various conversion processes
Catalytic Cracking unit (usually a Fluidised Catalytic Cracking unit (FCC); some Thermofor Catalytic Cracking units (TCC) may still be in use).
These units take the residual oils (bottoms) and ‘crack’ the heavy molecules into lighter fractions gas, naphtha, middle distillates (gas oils) and heavy oils.
Figure 8.3 – FCC Unit showing the Large Reactor and Fractionating Towers
(Source: Petroch Services)
Catalytic Reformers, which take the low octane naphtha and catalytically reform the molecules in a hydrogen rich atmosphere to make high octane gasoline blend stocks
Alkylation Unit for the conversion of light hydrocarbon gases (propylene, butylene with iso butane) using an acid catalyst (Sulphuric or hydrofluoric, or phosphoric acid) to produce high octane (liquid) gasoline blend stocks
There are many other process units are described in Figure 8.4.
For more information on petroleum refining, refer to:
accessed Aug
US OSHA Technical Manual, SECTION IV: CHAPTER 2, PETROLEUM REFINING PROCESSES
accessed Aug

9. FCC Unit showing the Large Reactor and Fractionating Towers
Then the various conversion processes
Catalytic Cracking unit (usually a Fluidised Catalytic Cracking unit (FCC); some Thermofor Catalytic Cracking units (TCC) may still be in use).
These units take the residual oils (bottoms) and ‘crack’ the heavy molecules into lighter fractions gas, naphtha, middle distillates (gas oils) and heavy oils.
FCC Unit showing the Large Reactor and Fractionating Towers

10. Thermofor Catalytic Cracker
TCC is always the tallest unit in the refinery. There are not many left in the world due to better yields are obtained by FCC. Also the TCC technology was developed by Mobil Research Development Corp and so was used widely in Mobil refineries (these have been sold or become part of Exxon-Mobil), while FCC was developed by other research companies and used by Shell, BP, Esso

11. Small Fuels Refinery Small fuels refinery
Note Separation of storage tanks and process units Tall stack is for dispersion of odourous gas SO2
Small Fuels Refinery

12. Process flow for Fuels and lube refinery showing the following units
Desalting – to remove salt, water, contaminants prior to primary distillation
Atmospheric Distillation which separates the crude (by boiling range) into Gas, Light Straight Run (LSR) Naphtha, Heavy Straight Run (HSR) Naphtha, Straight Run (SR) Kerosene, Straight Run (SR) Middle Distillate, Straight Run (SR) Gas Oils and finally Atmospheric tower bottoms – Residual oil
Gas Separation – separates gas (C1-C4s) from the light crude distillate (C5+)
Gas Plant – separates (fractionation) into Fuel gas (Hydrogen, C1, C2) , LPG (C3 or C4) for sale or use in the refinery, Feedstock for Polymerisation Unit (which makes a gasoline blend stock), Feedstock (Isobutane, propylene, Butenes) for Alkylation Unit (which makes high octane alkylate for motor and aviation gasolines)
Catalytic Isomerization Unit – feedstock light crude distillate (C5+) from gas separation, converted to higher octane gasoline blend stock.
Hydrodesulphurization/Treating – feedstock Light SR Naphtha which is treated to remove sulphur compounds. Treating removes other contaminants such as lead, arsenic, oxygen, nitrogen prior to Catalytic Reforming
Catalytic Reforming – Feedstock treated LSR Naphtha low octane, converts to high octane (aromatic) gasoline blend stock
Note: one process unit missing from this process flow is a Benzene Reduction Unit (BRU). This unit takes aromatic gasoline streams and converts their Benzene content into Toluene in order that the Benzene content of the finished motor gasoline blended from all the gasoline stocks to <1% Benzene.
Catalytic Hydrocracking -
Vacuum Distillation – separates residual bottoms in Light Vac Distillate, Heavy Vac Distillate which are feedstock for Catalytic Cracking or Lube Refinery. Bottoms from the Vac Tower become the feedstock for the Bitumen plant
Catalytic Cracking. Cracks the gas oils and Vac distillates to produce a full range of petroleum intermediates from gas , gasoline blend stocks, diesels, residual fuel oil, most of which need treating
Lube Refinery process units - Solvent Extractions (Furfural), Solvent Dewaxing (MEK) Hydrotreating,
Further information and detail is available in hand out Refinery Processes.

13. Altona Saturates Gas Plant
Learning Points
The light gases from the fractionators separating naphthas and reformate come from the top of the debutanisers (1PtR, 2 PtR, 3 PtR and Naphtha Fractionation Unit. The composition is C2, C3, C4. traces of C5. It goes to the SGP Surge drum to eliminate pulses and maintain constant feed to the next operation. Caustic Wash . This removes traces of sulphur compounds Mercaptans, Disulphides. But to ensure no carry over to the next unit it is water washed. The stream then goes to Deethaniser where C2 Ethane is removed, then Recovery Tower where some isobutane is recovered for the Alkylation units and the overheads go to the Depropaniser where C3 Propane is recovered (overhead) and the bottoms C4 Butanes go to storage.
From this process flow diagram we can determine that most of the streams are asphyxiant gases, there are corrosives (Caustic Wash), and there may be mercury present in the gas streams and therefore in the exchangers and unit during turnarounds.

14. PROCESS FLOW – LUBE REFINERY
Vacuum Distillation - to process atmospheric tower residues and remove the light components (gas oils).
Extraction Process (Furfural) - to remove poly aromatic hydrocarbons (PAH or PNA)
Methyl Ethyl Ketone dewaxing - to remove wax
Hydrofinishing Unit - to remove unsaturated hydrocarbons leaving a finished lubricating base oil of various grades.
The Lube Oil Refinery process is somewhat simpler than a fuels refinery, and comprises a vacuum distillation tower to process the atmospheric tower residues and remove the light components (gas oils), then an extraction process (Furfural) to remove poly aromatic hydrocarbons (PAH or PNA), then a process to remove wax (Methyl Ethyl Ketone dewaxing), and finally a hydrofinishing unit to remove unsaturated hydrocarbons leaving a finished lubricating base oil of various grades.

15. Lube Oil Refinery Process Flow

16. The Lube Oil Refinery process is somewhat simpler than a fuels refinery, and comprises a vacuum distillation tower to process the atmospheric tower residues and remove the light components (gas oils), then an extraction process (Furfural) to remove poly aromatic hydrocarbons (PAH or PNA), then a process to remove wax (Methyl Ethyl Ketone dewaxing), and finally a hydrofinishing unit to remove unsaturated hydrocarbons leaving a finished lubricating base oil of various grades.

17. Fuel and Lube Processes
Refinery processes – broad categories
Fractionation Processes (Distillation)
Conversion Processes—decomposition
Conversion Processes—unification
Conversion Processes—alteration or rearrangement
Treatment Processes
Utilities
Refinery processes fall into the following broad categories
Fractionation Processes (Distillation) –Atmospheric distillation, Vacuum distillation
Conversion Processes—decomposition –Catalytic cracking, Coking, Hydro-cracking, *Hydrogen steam reforming, *Steam cracking, Visbreaking
Conversion Processes—unification –Alkylation, Grease compounding, Polymerizing, Asphalt Manufacture
Conversion Processes—alteration or rearrangement - Catalytic reforming, Isomerization, Benzene Reduction
Treatment Processes - Amine treating, Desalting, Drying & sweetening, *Furfural extraction, Hydro –desulphurization, Sulphur Recovery , Hydrotreating, *Phenol extraction, Solvent deasphalting, Solvent dewaxing, Solvent extraction, Sweetening, Gasoline Blending
Fuel and Lube Processes – Potential Hazards
Table 8.1 provides an overview of hazards that may arise during fuel and lube refining.

18. Understand the Process, Products and Hazards
Fractionation - Distillation
Process Name
Action &
Purpose
Feedstock
Product(s)
Potential Health Hazards
Atmos. distillation
Separation – Thermal,
Separate fractions
Desalted crude oil
Gas, naphtha, gas oil, distillate, residual
Hydrocarbons. (Paraffinic, Olefinic, Naphthenic, Aromatic, PAH, Carbon (Coke) H2S, Mercaptans. Heat, Noise, Insulation materials
Vacuum distillation
Separate without cracking
Atmos. tower residual
Gas oil, lube stock, residual
Hydrocarbons, (Paraffinic, Olefinic, Naphthenic, Aromatic, PAH, Carbon (Coke). Heat, Noise, Insulation materials
Refer to Student manual for the other refinery processes

19. CONVERSION PROCESSES—DECOMPOSITION
Catalytic cracking
Alter (crack) molecules Catalytic,
Upgrade gasoline
Gas oil, coke distillate
Gasoline blend stock, petrochemical feedstock
Hydrocarbons, Carbon (Coke) including Benzene
Aromatic oils, PAH, Carbon Monoxide, H2S, Mercaptans. Sulphur oxides. Gases, Catalyst dust, Heat, Noise, Insulation materials
Coking
Polymerize/ desulphur. Thermal,
Convert vacuum residuals
Gasoline blend stock,, petrochemical feedstock, coke
Hydrocarbons including Benzene (~2%%), Aromatic oils, PAH Carbon Monoxide, H2S, coke dust, Heat, Noise, Insulation materials
Hydro-cracking
Hydrog. Catalytic,
Convert to lighter Hydrocarbons
Gas oil, cracked oil, residual
Gasoline blend stock,, Lighter, higher-quality products
Hydrocarbons, Gasoline Hydrogen, Carbon Monoxide, CO2, H2S, Mercaptans. Sulphur oxides, Metal Carbonyls, Metal sulphides, Catalyst dust, Heat, Noise, Insulation materials

20. CONVERSION PROCESSES—UNIFICATION
Alkylation
Combining gases
Catalytic (Sulphuric, or Hydrofluoric, or Phosphoric) Acid
Combine olefins & isoparaffins
Atm. tower & Cracker isobutane/ cracker olefin
Iso-octane (alkylate) Gasoline blend stock,
Hydrocarbons (Paraffins, Olefins), Gases, Caustics, Amines, Acids (Sulphuric or Hydrofluoric, or Phosphoric) Acid sludge, Noise

21. Alkylation Unit Alkylation Unit Process Flow Alkylation Unit
Sulphuric Acid storage tanks in foreground, four fractionation towers in centre.

22. Alkylation Process – Sulphuric Acid
Isobutane + Olefins Propylenes Butenes Butylenes
Alkylation Process – Sulphuric Acid Type
91-93% Sulphuric Acid
Feed gases from FCC or TCC or unsaturated gases n-Propylene, isopropylene, butylene (normal & iso-), Butenes
Produces Light alkylate predominantly C7, C8 highly branched paraffins - trimethyl pentanes, dimethyl pentanes, dimethyl hexanes

23. Alkylation Process – Aviation gasoline, high octane blend stock
Light Alkylate C7 to C8 highly branched paraffins
RON ~ 94 (unleaded)
Includes 2,2,4 Trimethyl Pentane (‘Iso Octane’)
Octane rating standard = 100
Normal Heptane, octane rating standard = 0

24. CONVERSION PROCESSES—ALTERATION OR REARRANGEMENT
Catalytic reforming
Alteration/ dehydr. Catalytic
Upgrade low-octane naphtha
Coker/ hydro-cracker naphtha
High octane Reformate/ aromatic
Hydrocarbons, H2S, Benzene, Catalyst dust. Metal Carbonyls, Metal sulphides, Heat, Noise, Insulation materials, Hydrogen
Isomerization
Rearrange Catalytic
Convert straight chain to branch
Butane, pentane, hexane
Isobutane/ isopentane/ isohexane
Hydrocarbons, Hydrogen, Hydrogen Chloride, Aluminium Chloride, Antimony Chloride, Catalyst dust, Heat, Noise
Benzene Reduction
Hydrog. Catalytic
Convert Benzene into branched hydrocarbon
Reformate (Benzene 5-10%)
Gasoline blend stock Benzene (<1%)
Hydrocarbons, Hydrogen, Metal Carbonyls, Metal sulphides, Catalyst dust, Heat, Noise, Insulation materials

25. TREATMENT PROCESSES Amine treating Treatment Absorption
Remove acidic contaminants
Sour gas, H/C, CO2 H2S, RSH
Acid free gases & liquid hydrocarbons
Hydrocarbons CO2 ,H2S, Mercaptans, Amines, Caustic
Desalting
Dehydration/ Electrostatic
Absorption
Crude oil
Desalted crude oil
Hydrocarbons, H2S, Mercaptans
Drying & sweeten
Treatment Absorption/ thermal
Liquid H/Cs, LPG, alky feedstock
Sweet & dry hydrocarbons
Hydrocarbons, CO2 ,H2S, Mercaptans, Amines, Caustic
Furfural extraction
Solvent extraction. Absorption
Upgrade lubes
Cycle oils & lube feed-stocks
High quality diesel & lube oil
Hydrocarbons, PAH, Furfural
Hydro –desulphur.
Treatment Catalytic
Remove sulphur, contaminants
High-sulphur residual/ gas oil/kerosene
Desulph. product
Sulphur Recovery
Convert high sulphur gas to elemental sulphur
H2S gas
Elemental sulphur
H2S, Mercaptans, light H/C gases. Sulphur, CO, Heat, Noise

26. Utilities - 1
Steam Generation –heat, noise, H2S, sulphur dioxide, water treatment chemicals, CO, CO2, hydrocarbons, insulation materials (asbestos, SMF)
Power Generation – Gas turbine power generation to provide electrical services. High noise source from gas turbines.
Cooling Towers – Hazards from contamination of cooling water by process streams and water treatment chemicals.
Additives, Corrosion inhibitors Chemicals - chlorine, algaecides, chromates, zinc, dichromates, organic phosphate.
Potential source of Legionella
Noise from fans and pumps.
Utilities
On every refinery site there are a number of utilities that can give rise to potential health issues. These include:
 Steam Generation –heat, noise, H2S, sulphur dioxide, water treatment chemicals, carbon monoxide, carbon dioxide, hydrocarbons, insulation materials (asbestos, SMF)
 Power Generation – Some remote facilities may also have gas turbine power generation to provide electrical services to the site. These can be a high noise source from gas turbines.
 Cooling Towers – The potential hazards arise mainly from the contamination of the cooling water by process streams and water treatment chemicals. These chemicals include additives and inhibitors to prevent corrosion, scale formation and formation of algae. The chemicals are chlorine, algaecides, chromates, zinc, dichromates, organic phosphate, and in the past arsenates. Because the additives and inhibitors are generally non-volatile, the potential problems are related to materials handling. Chlorine, however when used in large amounts can pose a significant hazard if mishandled. Cooling towers can also be a potential source of Legionella if water treatment is not correctly maintained. Other hazards include noise from fans and pumps.
 Waste Water Treatment – The hazards encountered in waste water and disposal systems are gases, liquids or particulates and include those associated with petroleum refinery operations. These also include acids, alkali, metal salts, zeolites, silicious dust, chlorine, chlorine dioxide, carbon monoxide, carbon dioxide, alcohols, hydrogen sulphide, benzene, disulphides. Heat and noise from incinerators.

27. Utilities - 2
Waste Water Treatment – Hazards are gases, liquids or particulates.
Also include acids, alkali, metal salts, zeolites, silicious dust, chlorine, chlorine dioxide, CO, CO2, alcohols, hydrogen sulphide, benzene, disulphides. Heat and noise from incinerators.
Flares - Heat and noise, gases, (liquids), steam

28. Maintenance & Workshops
Maintenance activities can be grouped into three categories:
Preventative (scheduled) maintenance – planned inspections
Emergency (non-scheduled) maintenance, repairs of failed equipment
“Turnarounds” – shutdown and major overhaul and inspections (taking 5 to 40 days).
Preventative (scheduled) maintenance, which includes daily/weekly inspections to determine the status of the equipment and need for repairs
Emergency (non-scheduled) maintenance, repairs of failed equipment (sometimes associated with fire and explosion)
“Turnarounds” – shutdown and major overhaul and inspections (taking 5 to 40 days). Major purpose of inspections is to determine whether various components might have surpassed their recommended limits of wear and stress

29. Petroleum Refining (Fuel & Lube) Processes and Their Potential Health Hazards
Hydrocarbons. (Paraffinic, Olefinic, Naphthenic, Aromatic, Benzene, PAH, Carbon (Coke), Aromatic oils, PAH (boiling point >385 deg C)
Hydrogen, Carbon Monoxide, Carbon Dioxide, H2S, Mercaptans, Sulphur oxides, Gases
Catalyst dust, Metal Carbonyls, Metal sulphides
Caustics, Amines, Acids (Sulphuric or Hydrofluoric, or Phosphoric) Acid sludge
Heat, Noise, Insulation materials.
The above list is not inclusive and there are many other potentials hazards such as those encountered in grease manufacture, utilities, shutdowns, waste treatment.
Refer Table 8.1 Petroleum Refining (Fuel & Lube) Processes and Their Potential Health Hazards

30. OH Issues For Refineries
a) Hazardous Substances
b) Thermal Environment
c) Noise
d) Asbestos and Other Fibres
e) Ergonomic
f) Radiation
g) Maintenance & Turnaround Hazards
h) Other Hazards
i) Environmental hazards
Occupational Hygiene Issues For Refineries
The following is a list of issues which may arise on refinery sites.
a) Hazardous Substances
There are four groups:
Process streams and contaminants – crude oil, (condensate), Mercury, Hydrogen sulphide and sulphur compounds
Purchased chemicals and products – catalysts, treatment chemicals (amines, caustic) - this requires a chemical inventory and MSDS information
Generated hazardous substances such as welding fume, catalyst dust
Generated waste and waste disposal
b) Thermal Environment
General environment depending upon location
c) Noise
Noise from process units, utilities and maintenance activities
d).. Asbestos and Other Fibres
Insulation (acoustic and thermal); many of the refineries were built before 1980’s when asbestos insulation was a common thermal and fire protection insulation
e) Ergonomic hazards
Ergonomic hazards associated with any facility
f) Radiation, both ionising and non-ionising
Ionising - Radiation sources are used (for level measurement). Radiography assessment
NORM (Naturally Occurring Radioactive Material) - NORM is usually not a significant problem in refineries and nearly all the NORM has been retained in the upstream gas plants near the crude oil source
Non-Ionising - Visible - Lighting
UV radiation (sun, welding)
g) Maintenance & Turnaround Hazards
Hazards associated with maintenance activities, this also includes confined spaces hazards
h) Other Hazards
Generally refineries are located in populated areas, close to shipping access, therefore the hazards associated with remote and isolated operations do not apply. However other subjects come into consideration – public safety, site security, community impact
i) Environmental Hazards
Earthquakes, hurricanes, flood, and fire, etc.

31. OH Issues (a) Hazardous Substances
• Process streams and contaminants – crude oil, (condensate), Mercury, Hydrogen sulphide and sulphur compounds
• Purchased chemicals and products – catalysts, treatment chemicals (amines, caustic) - this requires a chemical inventory and MSDS information
• Generated substances e.g. welding fume, catalyst dust
• Generated waste and waste disposal
Odour control - environmental
Note Radon is not usually encountered in the refinery process because it usually retained at the gas and crude stabilization plant .
Odour control becomes an issue because of the location in a populated area.
Hazardous Substances
There are four groups:
Process streams and contaminants – crude oil, natural gas, (condensate), Mercury, Hydrogen sulphide and sulphur compounds
Purchased chemicals and products – catalysts, treatment chemicals (amines, caustic) - this requires a chemical inventory and MSDS information
Generated hazardous substances such as welding fume, catalyst dust
Generated waste and waste disposal

32. OH Issues (b) Thermal Environment
General environment & location
Refineries usually located on land in populated areas relatively close access to shipping and/or pipelines. This can be in cold or hot climates.
Thermal Environment
General environment depending upon location

33. OH Issues (c) Noise
Noise from process units, utilities and maintenance activities
High noise sources are heaters, compressors and generators (typically >105 dBA) however with modern designs and improved engineering the refineries may be able to achieve noise levels < 85 dBA
Community noise becomes an issue
high noise sources are compressors and generators (typically >105 dBA) however with modern designs and improved engineering the new platforms may be able to achieve noise levels < 85 dBA
Community noise becomes an issue because the refinery is located in a populated area

34. OH Issues (d) Asbestos and Other Fibres
Asbestos and Other Fibres: Insulation (acoustic and thermal)
Removal of asbestos insulation

35. OH Issues (e) Ergonomic
Ergonomic hazards associated with any facility
Opening/closing valves – poor posture
e) Ergonomic hazards associated with any facility

36. OH Issues (f) Radiation
Ionizing – Radiation – level measurement, radiography
Non-Ionizing Radiation- Visible – Lighting
UV radiation (sun, welding)
NORM (Naturally Occurring Radioactive Material) - usually not a significant problem in refineries as nearly all the NORM has been retained in upstream gas plants near the crude oil source
f) Radiation
• Ionising - Radiation sources are used (for level measurement). Radiography assessment
NORM (Naturally Occurring Radioactive Material) - NORM is usually not a significant problem in refineries and nearly all the NORM has been retained in the upstream gas plants near the crude oil source
Non-Ionising - Visible - Lighting
UV radiation (sun, welding)

37. Radiation – FCC Level Gauge

38. OH Issues (g) Maintenance & Turnarounds
Planned and unplanned shutdowns
Potential release of product
Inspection of process equipment both external and internal – confined space entry
Turnarounds
– Increased workforce – trained & untrained
Untrained and unskilled workforce need training on O&G hazards
In any O&G process whenever maintenance occurs there is the potential for product release and exposure of both workers and the surrounding workforce and community. The reason is that a normally closed process is now opened – removal of valves, pumps, damaged pipework.
There is also preventative maintenance – inspections of equipment both externally and internally (confined space entry)
Turnarounds are planned plant shutdowns
Hazards associated with maintenance and turnaround activities when the workforce is increased with contractors who may be untrained and unskilled.

39. OH Issues (h) Other Hazards
Location hazards – on land, insects, disease (Cholera, Malaria, HIV)
Legionella (from cooling towers)
Civil Unrest - stability of government
Security of site.
Generally refineries are located in populated areas, therefore the hazards associated with remote and isolated operations do not apply. However other subjects come into consideration – public safety, site security, community impact - environmental
Other Hazards -Location hazards – on land, predatory animals, insects, disease (Cholera, Malaria, HIV), stability of government
Generally refineries are located in populated areas, close to shipping access, therefore the hazards associated with remote and isolated operations do not apply. However other subjects come into consideration – public safety, site security, community impact environmental – noise, odours, etc.

40. OH Issues (i) Environmental Hazards
Environmental hazards – earthquakes, hurricanes, flood, and fire
Environmental hazards – earthquakes, hurricanes, flood, and fire

41. Other hazards – LPG
Joules-Thompson effect, expansion of LPG through valve takes latent heat from surroundings causing the pipes to cool to the point when moisture in the air condenses and forms ice in the lines and valves. This can lead to the freezing of the valves in the open position and result in uncontrolled release of LPG.

42. Health Hazards of Some Petroleum Operations
Boiler house - Noise, Asbestos insulation, SMF insulation, Water treatment chemicals
Cooling towers - Water treatment chemicals, Legionella
Waste water treatment - Water treatment chemicals, hydrocarbons
Drum fill operations - Hydrocarbons, Noise, ergonomics (manual handling) – Various types of filling
Tank truck fill operations & driving - Hydrocarbons, Noise, ergonomics (manual handling), driver fatigue – Various types of loading
Rail car fill operations - Hydrocarbons, Noise, ergonomics (manual handling) – Various types of loading
Ship loading operations - Hydrocarbons, Noise, ergonomics (manual handling) - Various types of loading
Location/Operations Hazard Comments
Boiler house Noise, Asbestos insulation, SMF insulation, Water treatment chemicals
See Refineries above
Cooling towers Water treatment chemicals, Legionella
Waste water treatment
Drum fill operations Exposure to hydrocarbons, Noise, ergonomics (manual handling)
Types of filling operations: (a) spear, (b) hose with camlock fittings, (c) stub with vapour extraction
Tank truck fill operations & driving Exposure to hydrocarbons, Noise,
ergonomics (manual handling), driver fatigue
Types of loading:
(a) Top loading with spear or hose with camlock fittings
(b) Bottom loading with or without vapour extraction/recovery
Rail car fill operations Exposure to hydrocarbons, Noise, ergonomics (manual handling)
(a) Top loading with spear or hose with camlock fittings.
Ship loading operations Exposure to hydrocarbons, Noise, ergonomics (manual handling) Chicksan loading arm, hoses
Tank Cleaning Exposure to hydrocarbons, Noise, lead (alky lead), PAH (oils), confined spaces, ergonomics (manual handling)
Removal of product, hydro blasting and water washing tanks. Use of
compressed air (breathing air)
Tank repairs Exposure to hydrocarbons, Noise, lead (alky lead), lead based paints, epoxy paints, confined spaces, welding fumes, dust
Repair of tank floors, grinding, welding, grit blasting, repainting
internals
Maintenance/Workshop Cleaning chemicals, carbon monoxide
in motor garages
Warehouse operations Carbon monoxide from forklifts. ergonomics (manual handling) Movement of drums, loading trucks
Waste product recovery, drum cleaning Exposure to hydrocarbons, Noise, ergonomics (manual handling) Decanting of product, emptying of drums
Fuel Testing Laboratory Exposure to hydrocarbons, Noise, ergonomics (manual handling), alkyl lead, chemicals
Engine laboratory (knock engine operators), lab technicians/chemists

43. Health Hazards of Some Petroleum Operations
Tank Cleaning - Hydrocarbons, Noise, lead (alky lead), PAH (oils), confined spaces, ergonomics (manual handling), hydro blasting and water washing tanks. Use of compressed air (breathing air) Tank repairs - Hydrocarbons, Noise, lead (alky lead), lead based paints, epoxy paints, confined spaces, welding fumes, dust Repair of tank floors, grinding, welding, grit blasting, repainting internals Maintenance/Workshop - Cleaning chemicals, carbon monoxide

44. Tank Repair – Confined Space
Welding inside a tank repairing the tanks floor
Manhole into tank with electrical cables, welding gas hoses

45. Health Hazards of Some Petroleum Operations
Warehouse operations - CO, forklifts, ergonomics (manual handling) movement of drums, loading trucks Waste product recovery, drum cleaning - Hydrocarbons, Noise, ergonomics (manual handling) Fuel Testing Laboratory - Hydrocarbons, Noise, ergonomics (manual handling), alkyl lead, chemicals, Engine laboratory (knock engine operators), lab technicians/chemists

46. Health Hazards of Some Petroleum Products
Gasoline
Benzene Skin, eye contact, vapour inhalation
Long term exposure to Benzene may result in blood disorders – leukaemia
Skin, eye irritation, respiratory irritation, dizziness, loss of consciousness
Kero. Heating oil
Skin, eye contact Excessive inhalation unlikely, however if product is aspirated (sprayed) then potential respiratory hazards
Skin, eye irritation. Repeated exposure may cause skin dryness or cracking.
May cause lung damage if swallowed.
Gas oils, Diesels, Residual Fuels
Skin, eye contact.
Excessive inhalation unlikely however if product is aspirated (sprayed) then potential respiratory hazards, Polyaromatic Hydrocarbons (PAH, PCA)
Skin, eye irritation, Repeated exposure may cause skin dryness or cracking.
In extreme cases of poor personal hygiene and prolonged and repeated contact there may be a possibility of skin cancer
Product Hazard Health Hazard Gasoline Benzene (generally <1%, was up to 5%, and greater in some earlier grades in the 1960’s) Skin, eye contact, vapour inhalationLong term exposure to Benzene may result in blood disorders – leukaemia Skin, eye irritation, respiratory irritation, dizziness, loss of consciousness Kerosene. Heating oilskin, eye contact Excessive inhalation is unlikely due to low vapour pressure, however if product is aspirated (sprayed) then potential respiratory hazards can occur Skin, eye irritation. Repeated exposure may cause skin dryness or cracking. May cause lung damage if swallowed. Gas oils, Diesels, Residual Fuels Skin, eye contact. Excessive inhalation is unlikely due to low vapour pressure, however if product is aspirated (sprayed) then potential respiratory hazards can occur Polyaromatic Hydrocarbons (PAH, PCA) Skin, eye irritation, Repeated exposure may cause skin dryness or cracking. May cause lung damage if swallowed. In extreme cases of pour personal hygiene and prolonged and repeated contact there may be a possibility of skin cancer

47. Summary
Understand the Process, Products, Hazards and observe what People do
Processes – What are the operations?
Products – What are the components?
Potential Hazards – What are the hazards? (chemical, noise, thermal, radiation, asbestos & fibres, ergonomics, biological, other considerations, environment)
People - What they do? Routine and non routine (maintenance, turnarounds)

48. End of Section 8
Refineries